1478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 2478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * pcap-linux.c: Packet capture interface to the Linux kernel 3478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 4478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Copyright (c) 2000 Torsten Landschoff <torsten@debian.org> 5478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Sebastian Krahmer <krahmer@cs.uni-potsdam.de> 6478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 7478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * License: BSD 8478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 9478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Redistribution and use in source and binary forms, with or without 10478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * modification, are permitted provided that the following conditions 11478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * are met: 12478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 13478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 1. Redistributions of source code must retain the above copyright 14478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * notice, this list of conditions and the following disclaimer. 15478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 2. Redistributions in binary form must reproduce the above copyright 16478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * notice, this list of conditions and the following disclaimer in 17478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the documentation and/or other materials provided with the 18478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * distribution. 19478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 3. The names of the authors may not be used to endorse or promote 20478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * products derived from this software without specific prior 21478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * written permission. 22478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 23478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 24478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 25478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 26478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 27478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 28478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifndef lint 29478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic const char rcsid[] _U_ = 30478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "@(#) $Header: /tcpdump/master/libpcap/pcap-linux.c,v 1.110.2.14 2006/10/12 17:26:58 guy Exp $ (LBL)"; 31478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 32478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 33478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 34478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Known problems with 2.0[.x] kernels: 35478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 36478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * - The loopback device gives every packet twice; on 2.2[.x] kernels, 37478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * if we use PF_PACKET, we can filter out the transmitted version 38478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * of the packet by using data in the "sockaddr_ll" returned by 39478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * "recvfrom()", but, on 2.0[.x] kernels, we have to use 40478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * PF_INET/SOCK_PACKET, which means "recvfrom()" supplies a 41478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * "sockaddr_pkt" which doesn't give us enough information to let 42478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * us do that. 43478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 44478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * - We have to set the interface's IFF_PROMISC flag ourselves, if 45478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * we're to run in promiscuous mode, which means we have to turn 46478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * it off ourselves when we're done; the kernel doesn't keep track 47478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * of how many sockets are listening promiscuously, which means 48478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * it won't get turned off automatically when no sockets are 49478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * listening promiscuously. We catch "pcap_close()" and, for 50478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * interfaces we put into promiscuous mode, take them out of 51478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * promiscuous mode - which isn't necessarily the right thing to 52478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * do, if another socket also requested promiscuous mode between 53478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the time when we opened the socket and the time when we close 54478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the socket. 55478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 56478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * - MSG_TRUNC isn't supported, so you can't specify that "recvfrom()" 57478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * return the amount of data that you could have read, rather than 58478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the amount that was returned, so we can't just allocate a buffer 59478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * whose size is the snapshot length and pass the snapshot length 60478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * as the byte count, and also pass MSG_TRUNC, so that the return 61478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * value tells us how long the packet was on the wire. 62478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 63478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * This means that, if we want to get the actual size of the packet, 64478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * so we can return it in the "len" field of the packet header, 65478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * we have to read the entire packet, not just the part that fits 66478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * within the snapshot length, and thus waste CPU time copying data 67478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * from the kernel that our caller won't see. 68478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 69478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * We have to get the actual size, and supply it in "len", because 70478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * otherwise, the IP dissector in tcpdump, for example, will complain 71478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * about "truncated-ip", as the packet will appear to have been 72478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * shorter, on the wire, than the IP header said it should have been. 73478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 74478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 75478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 76478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#include <stdlib.h> 77478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef HAVE_CONFIG_H 78478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#include "config.h" 79478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 80478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 81478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#include "pcap-int.h" 82478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#include "sll.h" 83478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 84478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef HAVE_DAG_API 85478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#include "pcap-dag.h" 86478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif /* HAVE_DAG_API */ 87478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 88478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef HAVE_SEPTEL_API 89478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#include "pcap-septel.h" 90478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif /* HAVE_SEPTEL_API */ 91478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 92478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#include <errno.h> 93478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#include <unistd.h> 94478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#include <fcntl.h> 95478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#include <string.h> 96478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#include <sys/socket.h> 97478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#include <sys/ioctl.h> 98478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#include <sys/utsname.h> 99478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#include <net/if.h> 100478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#include <netinet/in.h> 101478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#include <linux/if_ether.h> 102478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#include <net/if_arp.h> 103478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 104478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 105478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * If PF_PACKET is defined, we can use {SOCK_RAW,SOCK_DGRAM}/PF_PACKET 106478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * sockets rather than SOCK_PACKET sockets. 107478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 108478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * To use them, we include <linux/if_packet.h> rather than 109478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * <netpacket/packet.h>; we do so because 110478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 111478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * some Linux distributions (e.g., Slackware 4.0) have 2.2 or 112478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * later kernels and libc5, and don't provide a <netpacket/packet.h> 113478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * file; 114478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 115478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * not all versions of glibc2 have a <netpacket/packet.h> file 116478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * that defines stuff needed for some of the 2.4-or-later-kernel 117478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * features, so if the system has a 2.4 or later kernel, we 118478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * still can't use those features. 119478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 120478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * We're already including a number of other <linux/XXX.h> headers, and 121478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * this code is Linux-specific (no other OS has PF_PACKET sockets as 122478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * a raw packet capture mechanism), so it's not as if you gain any 123478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * useful portability by using <netpacket/packet.h> 124478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 125478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * XXX - should we just include <linux/if_packet.h> even if PF_PACKET 126478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * isn't defined? It only defines one data structure in 2.0.x, so 127478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * it shouldn't cause any problems. 128478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 129478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef PF_PACKET 130478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project# include <linux/if_packet.h> 131478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 132478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 133478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * On at least some Linux distributions (for example, Red Hat 5.2), 134478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * there's no <netpacket/packet.h> file, but PF_PACKET is defined if 135478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * you include <sys/socket.h>, but <linux/if_packet.h> doesn't define 136478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * any of the PF_PACKET stuff such as "struct sockaddr_ll" or any of 137478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the PACKET_xxx stuff. 138478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 139478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * So we check whether PACKET_HOST is defined, and assume that we have 140478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * PF_PACKET sockets only if it is defined. 141478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 142478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project# ifdef PACKET_HOST 143478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project# define HAVE_PF_PACKET_SOCKETS 144478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project# endif /* PACKET_HOST */ 145478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif /* PF_PACKET */ 146478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 147478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef SO_ATTACH_FILTER 148478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#include <linux/types.h> 149478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#include <linux/filter.h> 150478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 151478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 152478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifndef __GLIBC__ 153478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projecttypedef int socklen_t; 154478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 155478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 156478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifndef MSG_TRUNC 157478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 158478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * This is being compiled on a system that lacks MSG_TRUNC; define it 159478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * with the value it has in the 2.2 and later kernels, so that, on 160478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * those kernels, when we pass it in the flags argument to "recvfrom()" 161478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * we're passing the right value and thus get the MSG_TRUNC behavior 162478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * we want. (We don't get that behavior on 2.0[.x] kernels, because 163478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * they didn't support MSG_TRUNC.) 164478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 165478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#define MSG_TRUNC 0x20 166478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 167478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 168478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifndef SOL_PACKET 169478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 170478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * This is being compiled on a system that lacks SOL_PACKET; define it 171478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * with the value it has in the 2.2 and later kernels, so that we can 172478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * set promiscuous mode in the good modern way rather than the old 173478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 2.0-kernel crappy way. 174478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 175478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#define SOL_PACKET 263 176478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 177478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 178478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#define MAX_LINKHEADER_SIZE 256 179478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 180478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 181478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * When capturing on all interfaces we use this as the buffer size. 182478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Should be bigger then all MTUs that occur in real life. 183478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 64kB should be enough for now. 184478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 185478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#define BIGGER_THAN_ALL_MTUS (64*1024) 186478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 187478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 188478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Prototypes for internal functions 189478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 190478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic void map_arphrd_to_dlt(pcap_t *, int, int); 191478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int live_open_old(pcap_t *, const char *, int, int, char *); 192478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int live_open_new(pcap_t *, const char *, int, int, char *); 193478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int pcap_read_linux(pcap_t *, int, pcap_handler, u_char *); 194478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int pcap_read_packet(pcap_t *, pcap_handler, u_char *); 195478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int pcap_inject_linux(pcap_t *, const void *, size_t); 196478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int pcap_stats_linux(pcap_t *, struct pcap_stat *); 197478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int pcap_setfilter_linux(pcap_t *, struct bpf_program *); 198478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int pcap_setdirection_linux(pcap_t *, pcap_direction_t); 199478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic void pcap_close_linux(pcap_t *); 200478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 201478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 202478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Wrap some ioctl calls 203478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 204478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef HAVE_PF_PACKET_SOCKETS 205478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int iface_get_id(int fd, const char *device, char *ebuf); 206478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 207478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int iface_get_mtu(int fd, const char *device, char *ebuf); 208478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int iface_get_arptype(int fd, const char *device, char *ebuf); 209478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef HAVE_PF_PACKET_SOCKETS 210478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int iface_bind(int fd, int ifindex, char *ebuf); 211478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 212478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int iface_bind_old(int fd, const char *device, char *ebuf); 213478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 214478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef SO_ATTACH_FILTER 215478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int fix_program(pcap_t *handle, struct sock_fprog *fcode); 216478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int fix_offset(struct bpf_insn *p); 217478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int set_kernel_filter(pcap_t *handle, struct sock_fprog *fcode); 218478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int reset_kernel_filter(pcap_t *handle); 219478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 220478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic struct sock_filter total_insn 221478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project = BPF_STMT(BPF_RET | BPF_K, 0); 222478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic struct sock_fprog total_fcode 223478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project = { 1, &total_insn }; 224478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 225478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 226478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 227478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Get a handle for a live capture from the given device. You can 228478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * pass NULL as device to get all packages (without link level 229478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * information of course). If you pass 1 as promisc the interface 230478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * will be set to promiscous mode (XXX: I think this usage should 231478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * be deprecated and functions be added to select that later allow 232478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * modification of that values -- Torsten). 233478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 234478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * See also pcap(3). 235478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 236478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectpcap_t * 237478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectpcap_open_live(const char *device, int snaplen, int promisc, int to_ms, 238478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project char *ebuf) 239478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project{ 240478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project pcap_t *handle; 241478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project int mtu; 242478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project int err; 243478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project int live_open_ok = 0; 244478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project struct utsname utsname; 245478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 246478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef HAVE_DAG_API 247478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (strstr(device, "dag")) { 248478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return dag_open_live(device, snaplen, promisc, to_ms, ebuf); 249478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 250478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif /* HAVE_DAG_API */ 251478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 252478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef HAVE_SEPTEL_API 253478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (strstr(device, "septel")) { 254478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return septel_open_live(device, snaplen, promisc, to_ms, ebuf); 255478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 256478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif /* HAVE_SEPTEL_API */ 257478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 258478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Allocate a handle for this session. */ 259478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 260478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle = malloc(sizeof(*handle)); 261478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle == NULL) { 262478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(ebuf, PCAP_ERRBUF_SIZE, "malloc: %s", 263478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project pcap_strerror(errno)); 264478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return NULL; 265478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 266478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 267478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Initialize some components of the pcap structure. */ 268478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 269478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project memset(handle, 0, sizeof(*handle)); 270478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->snapshot = snaplen; 271478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->md.timeout = to_ms; 272478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 273478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 274478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * NULL and "any" are special devices which give us the hint to 275478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * monitor all devices. 276478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 277478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (!device || strcmp(device, "any") == 0) { 278478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project device = NULL; 279478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->md.device = strdup("any"); 280478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (promisc) { 281478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project promisc = 0; 282478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Just a warning. */ 283478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(ebuf, PCAP_ERRBUF_SIZE, 284478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "Promiscuous mode not supported on the \"any\" device"); 285478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 286478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 287478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } else 288478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->md.device = strdup(device); 289478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 290478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->md.device == NULL) { 291478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(ebuf, PCAP_ERRBUF_SIZE, "strdup: %s", 292478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project pcap_strerror(errno) ); 293478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project free(handle); 294478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return NULL; 295478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 296478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 297478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 298478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Current Linux kernels use the protocol family PF_PACKET to 299478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * allow direct access to all packets on the network while 300478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * older kernels had a special socket type SOCK_PACKET to 301478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * implement this feature. 302478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * While this old implementation is kind of obsolete we need 303478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * to be compatible with older kernels for a while so we are 304478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * trying both methods with the newer method preferred. 305478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 306478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 307478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if ((err = live_open_new(handle, device, promisc, to_ms, ebuf)) == 1) 308478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project live_open_ok = 1; 309478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project else if (err == 0) { 310478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Non-fatal error; try old way */ 311478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (live_open_old(handle, device, promisc, to_ms, ebuf)) 312478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project live_open_ok = 1; 313478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 314478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (!live_open_ok) { 315478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 316478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Both methods to open the packet socket failed. Tidy 317478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * up and report our failure (ebuf is expected to be 318478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * set by the functions above). 319478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 320478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 321478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->md.device != NULL) 322478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project free(handle->md.device); 323478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project free(handle); 324478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return NULL; 325478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 326478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 327478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 328478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Compute the buffer size. 329478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 330478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * If we're using SOCK_PACKET, this might be a 2.0[.x] kernel, 331478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * and might require special handling - check. 332478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 333478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->md.sock_packet && (uname(&utsname) < 0 || 334478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project strncmp(utsname.release, "2.0", 3) == 0)) { 335478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 336478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * We're using a SOCK_PACKET structure, and either 337478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * we couldn't find out what kernel release this is, 338478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * or it's a 2.0[.x] kernel. 339478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 340478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * In the 2.0[.x] kernel, a "recvfrom()" on 341478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * a SOCK_PACKET socket, with MSG_TRUNC set, will 342478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * return the number of bytes read, so if we pass 343478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * a length based on the snapshot length, it'll 344478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * return the number of bytes from the packet 345478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * copied to userland, not the actual length 346478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * of the packet. 347478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 348478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * This means that, for example, the IP dissector 349478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * in tcpdump will get handed a packet length less 350478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * than the length in the IP header, and will 351478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * complain about "truncated-ip". 352478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 353478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * So we don't bother trying to copy from the 354478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * kernel only the bytes in which we're interested, 355478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * but instead copy them all, just as the older 356478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * versions of libpcap for Linux did. 357478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 358478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * The buffer therefore needs to be big enough to 359478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * hold the largest packet we can get from this 360478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * device. Unfortunately, we can't get the MRU 361478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * of the network; we can only get the MTU. The 362478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * MTU may be too small, in which case a packet larger 363478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * than the buffer size will be truncated *and* we 364478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * won't get the actual packet size. 365478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 366478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * However, if the snapshot length is larger than 367478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the buffer size based on the MTU, we use the 368478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * snapshot length as the buffer size, instead; 369478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * this means that with a sufficiently large snapshot 370478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * length we won't artificially truncate packets 371478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * to the MTU-based size. 372478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 373478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * This mess just one of many problems with packet 374478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * capture on 2.0[.x] kernels; you really want a 375478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 2.2[.x] or later kernel if you want packet capture 376478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * to work well. 377478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 378478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project mtu = iface_get_mtu(handle->fd, device, ebuf); 379478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (mtu == -1) { 380478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project pcap_close_linux(handle); 381478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project free(handle); 382478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return NULL; 383478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 384478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->bufsize = MAX_LINKHEADER_SIZE + mtu; 385478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->bufsize < handle->snapshot) 386478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->bufsize = handle->snapshot; 387478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } else { 388478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 389478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * This is a 2.2[.x] or later kernel (we know that 390478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * either because we're not using a SOCK_PACKET 391478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * socket - PF_PACKET is supported only in 2.2 392478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * and later kernels - or because we checked the 393478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * kernel version). 394478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 395478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * We can safely pass "recvfrom()" a byte count 396478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * based on the snapshot length. 397478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 398478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * If we're in cooked mode, make the snapshot length 399478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * large enough to hold a "cooked mode" header plus 400478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 1 byte of packet data (so we don't pass a byte 401478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * count of 0 to "recvfrom()"). 402478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 403478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->md.cooked) { 404478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->snapshot < SLL_HDR_LEN + 1) 405478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->snapshot = SLL_HDR_LEN + 1; 406478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 407478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->bufsize = handle->snapshot; 408478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 409478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 410478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Allocate the buffer */ 411478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 412478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->buffer = malloc(handle->bufsize + handle->offset); 413478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (!handle->buffer) { 414478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(ebuf, PCAP_ERRBUF_SIZE, 415478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "malloc: %s", pcap_strerror(errno)); 416478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project pcap_close_linux(handle); 417478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project free(handle); 418478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return NULL; 419478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 420478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 421478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 422478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * "handle->fd" is a socket, so "select()" and "poll()" 423478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * should work on it. 424478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 425478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->selectable_fd = handle->fd; 426478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 427478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->read_op = pcap_read_linux; 428478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->inject_op = pcap_inject_linux; 429478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->setfilter_op = pcap_setfilter_linux; 430478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->setdirection_op = pcap_setdirection_linux; 431478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->set_datalink_op = NULL; /* can't change data link type */ 432478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->getnonblock_op = pcap_getnonblock_fd; 433478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->setnonblock_op = pcap_setnonblock_fd; 434478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->stats_op = pcap_stats_linux; 435478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->close_op = pcap_close_linux; 436478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 437478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return handle; 438478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project} 439478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 440478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 441478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Read at most max_packets from the capture stream and call the callback 442478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * for each of them. Returns the number of packets handled or -1 if an 443478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * error occured. 444478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 445478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int 446478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectpcap_read_linux(pcap_t *handle, int max_packets, pcap_handler callback, u_char *user) 447478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project{ 448478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 449478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Currently, on Linux only one packet is delivered per read, 450478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * so we don't loop. 451478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 452478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return pcap_read_packet(handle, callback, user); 453478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project} 454478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 455478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 456478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Read a packet from the socket calling the handler provided by 457478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the user. Returns the number of packets received or -1 if an 458478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * error occured. 459478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 460478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int 461478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectpcap_read_packet(pcap_t *handle, pcap_handler callback, u_char *userdata) 462478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project{ 463478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project u_char *bp; 464478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project int offset; 465478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef HAVE_PF_PACKET_SOCKETS 466478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project struct sockaddr_ll from; 467478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project struct sll_header *hdrp; 468478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#else 469478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project struct sockaddr from; 470478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 471478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project socklen_t fromlen; 472478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project int packet_len, caplen; 473478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project struct pcap_pkthdr pcap_header; 474478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 475478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef HAVE_PF_PACKET_SOCKETS 476478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 477478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * If this is a cooked device, leave extra room for a 478478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * fake packet header. 479478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 480478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->md.cooked) 481478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project offset = SLL_HDR_LEN; 482478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project else 483478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project offset = 0; 484478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#else 485478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 486478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * This system doesn't have PF_PACKET sockets, so it doesn't 487478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * support cooked devices. 488478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 489478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project offset = 0; 490478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 491478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 492478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Receive a single packet from the kernel */ 493478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 494478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project bp = handle->buffer + handle->offset; 495478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project do { 496478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 497478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Has "pcap_breakloop()" been called? 498478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 499478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->break_loop) { 500478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 501478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Yes - clear the flag that indicates that it 502478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * has, and return -2 as an indication that we 503478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * were told to break out of the loop. 504478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 505478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->break_loop = 0; 506478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -2; 507478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 508478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project fromlen = sizeof(from); 509478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project packet_len = recvfrom( 510478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->fd, bp + offset, 511478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->bufsize - offset, MSG_TRUNC, 512478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project (struct sockaddr *) &from, &fromlen); 513478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } while (packet_len == -1 && errno == EINTR); 514478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 515478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Check if an error occured */ 516478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 517478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (packet_len == -1) { 518478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (errno == EAGAIN) 519478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return 0; /* no packet there */ 520478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project else { 521478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(handle->errbuf, sizeof(handle->errbuf), 522478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "recvfrom: %s", pcap_strerror(errno)); 523478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -1; 524478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 525478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 526478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 527478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef HAVE_PF_PACKET_SOCKETS 528478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (!handle->md.sock_packet) { 529478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 530478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Unfortunately, there is a window between socket() and 531478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * bind() where the kernel may queue packets from any 532478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * interface. If we're bound to a particular interface, 533478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * discard packets not from that interface. 534478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 535478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * (If socket filters are supported, we could do the 536478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * same thing we do when changing the filter; however, 537478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * that won't handle packet sockets without socket 538478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * filter support, and it's a bit more complicated. 539478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * It would save some instructions per packet, however.) 540478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 541478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->md.ifindex != -1 && 542478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project from.sll_ifindex != handle->md.ifindex) 543478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return 0; 544478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 545478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 546478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Do checks based on packet direction. 547478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * We can only do this if we're using PF_PACKET; the 548478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * address returned for SOCK_PACKET is a "sockaddr_pkt" 549478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * which lacks the relevant packet type information. 550478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 551478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (from.sll_pkttype == PACKET_OUTGOING) { 552478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 553478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Outgoing packet. 554478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * If this is from the loopback device, reject it; 555478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * we'll see the packet as an incoming packet as well, 556478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * and we don't want to see it twice. 557478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 558478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (from.sll_ifindex == handle->md.lo_ifindex) 559478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return 0; 560478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 561478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 562478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * If the user only wants incoming packets, reject it. 563478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 564478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->direction == PCAP_D_IN) 565478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return 0; 566478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } else { 567478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 568478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Incoming packet. 569478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * If the user only wants outgoing packets, reject it. 570478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 571478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->direction == PCAP_D_OUT) 572478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return 0; 573478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 574478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 575478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 576478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 577478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef HAVE_PF_PACKET_SOCKETS 578478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 579478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * If this is a cooked device, fill in the fake packet header. 580478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 581478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->md.cooked) { 582478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 583478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Add the length of the fake header to the length 584478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * of packet data we read. 585478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 586478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project packet_len += SLL_HDR_LEN; 587478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 588478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project hdrp = (struct sll_header *)bp; 589478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 590478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 591478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Map the PACKET_ value to a LINUX_SLL_ value; we 592478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * want the same numerical value to be used in 593478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the link-layer header even if the numerical values 594478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * for the PACKET_ #defines change, so that programs 595478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * that look at the packet type field will always be 596478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * able to handle DLT_LINUX_SLL captures. 597478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 598478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project switch (from.sll_pkttype) { 599478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 600478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case PACKET_HOST: 601478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project hdrp->sll_pkttype = htons(LINUX_SLL_HOST); 602478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 603478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 604478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case PACKET_BROADCAST: 605478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project hdrp->sll_pkttype = htons(LINUX_SLL_BROADCAST); 606478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 607478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 608478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case PACKET_MULTICAST: 609478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project hdrp->sll_pkttype = htons(LINUX_SLL_MULTICAST); 610478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 611478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 612478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case PACKET_OTHERHOST: 613478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project hdrp->sll_pkttype = htons(LINUX_SLL_OTHERHOST); 614478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 615478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 616478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case PACKET_OUTGOING: 617478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project hdrp->sll_pkttype = htons(LINUX_SLL_OUTGOING); 618478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 619478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 620478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project default: 621478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project hdrp->sll_pkttype = -1; 622478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 623478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 624478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 625478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project hdrp->sll_hatype = htons(from.sll_hatype); 626478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project hdrp->sll_halen = htons(from.sll_halen); 627478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project memcpy(hdrp->sll_addr, from.sll_addr, 628478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project (from.sll_halen > SLL_ADDRLEN) ? 629478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project SLL_ADDRLEN : 630478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project from.sll_halen); 631478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project hdrp->sll_protocol = from.sll_protocol; 632478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 633478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 634478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 635478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 636478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * XXX: According to the kernel source we should get the real 637478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * packet len if calling recvfrom with MSG_TRUNC set. It does 638478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * not seem to work here :(, but it is supported by this code 639478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * anyway. 640478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * To be honest the code RELIES on that feature so this is really 641478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * broken with 2.2.x kernels. 642478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * I spend a day to figure out what's going on and I found out 643478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * that the following is happening: 644478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 645478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * The packet comes from a random interface and the packet_rcv 646478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * hook is called with a clone of the packet. That code inserts 647478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the packet into the receive queue of the packet socket. 648478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * If a filter is attached to that socket that filter is run 649478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * first - and there lies the problem. The default filter always 650478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * cuts the packet at the snaplen: 651478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 652478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * # tcpdump -d 653478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * (000) ret #68 654478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 655478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * So the packet filter cuts down the packet. The recvfrom call 656478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * says "hey, it's only 68 bytes, it fits into the buffer" with 657478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the result that we don't get the real packet length. This 658478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * is valid at least until kernel 2.2.17pre6. 659478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 660478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * We currently handle this by making a copy of the filter 661478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * program, fixing all "ret" instructions with non-zero 662478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * operands to have an operand of 65535 so that the filter 663478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * doesn't truncate the packet, and supplying that modified 664478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * filter to the kernel. 665478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 666478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 667478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project caplen = packet_len; 668478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (caplen > handle->snapshot) 669478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project caplen = handle->snapshot; 670478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 671478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Run the packet filter if not using kernel filter */ 672478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (!handle->md.use_bpf && handle->fcode.bf_insns) { 673478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (bpf_filter(handle->fcode.bf_insns, bp, 674478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project packet_len, caplen) == 0) 675478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project { 676478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* rejected by filter */ 677478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return 0; 678478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 679478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 680478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 681478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Fill in our own header data */ 682478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 683478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (ioctl(handle->fd, SIOCGSTAMP, &pcap_header.ts) == -1) { 684478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(handle->errbuf, sizeof(handle->errbuf), 685478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "SIOCGSTAMP: %s", pcap_strerror(errno)); 686478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -1; 687478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 688478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project pcap_header.caplen = caplen; 689478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project pcap_header.len = packet_len; 690478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 691478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 692478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Count the packet. 693478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 694478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Arguably, we should count them before we check the filter, 695478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * as on many other platforms "ps_recv" counts packets 696478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * handed to the filter rather than packets that passed 697478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the filter, but if filtering is done in the kernel, we 698478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * can't get a count of packets that passed the filter, 699478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * and that would mean the meaning of "ps_recv" wouldn't 700478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * be the same on all Linux systems. 701478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 702478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * XXX - it's not the same on all systems in any case; 703478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * ideally, we should have a "get the statistics" call 704478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * that supplies more counts and indicates which of them 705478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * it supplies, so that we supply a count of packets 706478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * handed to the filter only on platforms where that 707478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * information is available. 708478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 709478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * We count them here even if we can get the packet count 710478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * from the kernel, as we can only determine at run time 711478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * whether we'll be able to get it from the kernel (if 712478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * HAVE_TPACKET_STATS isn't defined, we can't get it from 713478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the kernel, but if it is defined, the library might 714478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * have been built with a 2.4 or later kernel, but we 715478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * might be running on a 2.2[.x] kernel without Alexey 716478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Kuznetzov's turbopacket patches, and thus the kernel 717478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * might not be able to supply those statistics). We 718478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * could, I guess, try, when opening the socket, to get 719478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the statistics, and if we can not increment the count 720478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * here, but it's not clear that always incrementing 721478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the count is more expensive than always testing a flag 722478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * in memory. 723478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 724478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * We keep the count in "md.packets_read", and use that for 725478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * "ps_recv" if we can't get the statistics from the kernel. 726478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * We do that because, if we *can* get the statistics from 727478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the kernel, we use "md.stat.ps_recv" and "md.stat.ps_drop" 728478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * as running counts, as reading the statistics from the 729478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * kernel resets the kernel statistics, and if we directly 730478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * increment "md.stat.ps_recv" here, that means it will 731478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * count packets *twice* on systems where we can get kernel 732478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * statistics - once here, and once in pcap_stats_linux(). 733478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 734478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->md.packets_read++; 735478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 736478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Call the user supplied callback function */ 737478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project callback(userdata, &pcap_header, bp); 738478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 739478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return 1; 740478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project} 741478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 742478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int 743478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectpcap_inject_linux(pcap_t *handle, const void *buf, size_t size) 744478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project{ 745478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project int ret; 746478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 747478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef HAVE_PF_PACKET_SOCKETS 748478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (!handle->md.sock_packet) { 749478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* PF_PACKET socket */ 750478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->md.ifindex == -1) { 751478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 752478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * We don't support sending on the "any" device. 753478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 754478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project strlcpy(handle->errbuf, 755478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "Sending packets isn't supported on the \"any\" device", 756478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project PCAP_ERRBUF_SIZE); 757478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return (-1); 758478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 759478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 760478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->md.cooked) { 761478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 762478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * We don't support sending on the "any" device. 763478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 764478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * XXX - how do you send on a bound cooked-mode 765478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * socket? 766478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Is a "sendto()" required there? 767478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 768478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project strlcpy(handle->errbuf, 769478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "Sending packets isn't supported in cooked mode", 770478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project PCAP_ERRBUF_SIZE); 771478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return (-1); 772478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 773478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 774478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 775478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 776478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project ret = send(handle->fd, buf, size, 0); 777478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (ret == -1) { 778478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "send: %s", 779478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project pcap_strerror(errno)); 780478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return (-1); 781478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 782478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return (ret); 783478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project} 784478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 785478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 786478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Get the statistics for the given packet capture handle. 787478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Reports the number of dropped packets iff the kernel supports 788478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the PACKET_STATISTICS "getsockopt()" argument (2.4 and later 789478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * kernels, and 2.2[.x] kernels with Alexey Kuznetzov's turbopacket 790478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * patches); otherwise, that information isn't available, and we lie 791478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * and report 0 as the count of dropped packets. 792478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 793478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int 794478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectpcap_stats_linux(pcap_t *handle, struct pcap_stat *stats) 795478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project{ 796478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef HAVE_TPACKET_STATS 797478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project struct tpacket_stats kstats; 798478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project socklen_t len = sizeof (struct tpacket_stats); 799478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 800478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 801478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef HAVE_TPACKET_STATS 802478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 803478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Try to get the packet counts from the kernel. 804478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 805478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (getsockopt(handle->fd, SOL_PACKET, PACKET_STATISTICS, 806478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project &kstats, &len) > -1) { 807478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 808478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * On systems where the PACKET_STATISTICS "getsockopt()" 809478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * argument is supported on PF_PACKET sockets: 810478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 811478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * "ps_recv" counts only packets that *passed* the 812478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * filter, not packets that didn't pass the filter. 813478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * This includes packets later dropped because we 814478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * ran out of buffer space. 815478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 816478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * "ps_drop" counts packets dropped because we ran 817478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * out of buffer space. It doesn't count packets 818478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * dropped by the interface driver. It counts only 819478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * packets that passed the filter. 820478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 821478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Both statistics include packets not yet read from 822478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the kernel by libpcap, and thus not yet seen by 823478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the application. 824478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 825478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * In "linux/net/packet/af_packet.c", at least in the 826478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 2.4.9 kernel, "tp_packets" is incremented for every 827478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * packet that passes the packet filter *and* is 828478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * successfully queued on the socket; "tp_drops" is 829478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * incremented for every packet dropped because there's 830478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * not enough free space in the socket buffer. 831478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 832478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * When the statistics are returned for a PACKET_STATISTICS 833478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * "getsockopt()" call, "tp_drops" is added to "tp_packets", 834478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * so that "tp_packets" counts all packets handed to 835478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the PF_PACKET socket, including packets dropped because 836478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * there wasn't room on the socket buffer - but not 837478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * including packets that didn't pass the filter. 838478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 839478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * In the BSD BPF, the count of received packets is 840478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * incremented for every packet handed to BPF, regardless 841478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * of whether it passed the filter. 842478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 843478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * We can't make "pcap_stats()" work the same on both 844478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * platforms, but the best approximation is to return 845478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * "tp_packets" as the count of packets and "tp_drops" 846478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * as the count of drops. 847478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 848478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Keep a running total because each call to 849478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * getsockopt(handle->fd, SOL_PACKET, PACKET_STATISTICS, .... 850478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * resets the counters to zero. 851478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 852478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->md.stat.ps_recv += kstats.tp_packets; 853478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->md.stat.ps_drop += kstats.tp_drops; 854478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project *stats = handle->md.stat; 855478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return 0; 856478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 857478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project else 858478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project { 859478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 860478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * If the error was EOPNOTSUPP, fall through, so that 861478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * if you build the library on a system with 862478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * "struct tpacket_stats" and run it on a system 863478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * that doesn't, it works as it does if the library 864478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * is built on a system without "struct tpacket_stats". 865478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 866478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (errno != EOPNOTSUPP) { 867478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, 868478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "pcap_stats: %s", pcap_strerror(errno)); 869478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -1; 870478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 871478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 872478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 873478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 874478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * On systems where the PACKET_STATISTICS "getsockopt()" argument 875478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * is not supported on PF_PACKET sockets: 876478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 877478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * "ps_recv" counts only packets that *passed* the filter, 878478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * not packets that didn't pass the filter. It does not 879478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * count packets dropped because we ran out of buffer 880478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * space. 881478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 882478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * "ps_drop" is not supported. 883478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 884478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * "ps_recv" doesn't include packets not yet read from 885478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the kernel by libpcap. 886478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 887478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * We maintain the count of packets processed by libpcap in 888478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * "md.packets_read", for reasons described in the comment 889478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * at the end of pcap_read_packet(). We have no idea how many 890478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * packets were dropped. 891478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 892478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project stats->ps_recv = handle->md.packets_read; 893478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project stats->ps_drop = 0; 894478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return 0; 895478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project} 896478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 897478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 898478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Description string for the "any" device. 899478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 900478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic const char any_descr[] = "Pseudo-device that captures on all interfaces"; 901478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 902478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectint 903478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectpcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf) 904478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project{ 905478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (pcap_add_if(alldevsp, "any", 0, any_descr, errbuf) < 0) 906478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return (-1); 907478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 908478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef HAVE_DAG_API 909478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (dag_platform_finddevs(alldevsp, errbuf) < 0) 910478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return (-1); 911478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif /* HAVE_DAG_API */ 912478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 913478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef HAVE_SEPTEL_API 914478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (septel_platform_finddevs(alldevsp, errbuf) < 0) 915478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return (-1); 916478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif /* HAVE_SEPTEL_API */ 917478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 918478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return (0); 919478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project} 920478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 921478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 922478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Attach the given BPF code to the packet capture device. 923478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 924478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int 925478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectpcap_setfilter_linux(pcap_t *handle, struct bpf_program *filter) 926478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project{ 927478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef SO_ATTACH_FILTER 928478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project struct sock_fprog fcode; 929478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project int can_filter_in_kernel; 930478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project int err = 0; 931478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 932478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 933478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (!handle) 934478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -1; 935478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (!filter) { 936478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project strncpy(handle->errbuf, "setfilter: No filter specified", 937478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project sizeof(handle->errbuf)); 938478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -1; 939478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 940478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 941478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Make our private copy of the filter */ 942478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 943478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (install_bpf_program(handle, filter) < 0) 944478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* install_bpf_program() filled in errbuf */ 945478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -1; 946478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 947478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 948478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Run user level packet filter by default. Will be overriden if 949478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * installing a kernel filter succeeds. 950478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 951478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->md.use_bpf = 0; 952478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 953478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Install kernel level filter if possible */ 954478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 955478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef SO_ATTACH_FILTER 956478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef USHRT_MAX 957478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->fcode.bf_len > USHRT_MAX) { 958478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 959478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * fcode.len is an unsigned short for current kernel. 960478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * I have yet to see BPF-Code with that much 961478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * instructions but still it is possible. So for the 962478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * sake of correctness I added this check. 963478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 964478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project fprintf(stderr, "Warning: Filter too complex for kernel\n"); 965478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project fcode.len = 0; 966478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project fcode.filter = NULL; 967478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project can_filter_in_kernel = 0; 968478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } else 969478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif /* USHRT_MAX */ 970478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project { 971478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 972478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Oh joy, the Linux kernel uses struct sock_fprog instead 973478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * of struct bpf_program and of course the length field is 974478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * of different size. Pointed out by Sebastian 975478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 976478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Oh, and we also need to fix it up so that all "ret" 977478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * instructions with non-zero operands have 65535 as the 978478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * operand, and so that, if we're in cooked mode, all 979478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * memory-reference instructions use special magic offsets 980478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * in references to the link-layer header and assume that 981478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the link-layer payload begins at 0; "fix_program()" 982478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * will do that. 983478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 984478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project switch (fix_program(handle, &fcode)) { 985478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 986478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case -1: 987478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project default: 988478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 989478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Fatal error; just quit. 990478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * (The "default" case shouldn't happen; we 991478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * return -1 for that reason.) 992478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 993478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -1; 994478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 995478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case 0: 996478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 997478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * The program performed checks that we can't make 998478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * work in the kernel. 999478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1000478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project can_filter_in_kernel = 0; 1001478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1002478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1003478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case 1: 1004478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1005478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * We have a filter that'll work in the kernel. 1006478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1007478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project can_filter_in_kernel = 1; 1008478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1009478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1010478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1011478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1012478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (can_filter_in_kernel) { 1013478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if ((err = set_kernel_filter(handle, &fcode)) == 0) 1014478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project { 1015478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Installation succeded - using kernel filter. */ 1016478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->md.use_bpf = 1; 1017478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1018478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project else if (err == -1) /* Non-fatal error */ 1019478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project { 1020478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1021478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Print a warning if we weren't able to install 1022478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the filter for a reason other than "this kernel 1023478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * isn't configured to support socket filters. 1024478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1025478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (errno != ENOPROTOOPT && errno != EOPNOTSUPP) { 1026478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project fprintf(stderr, 1027478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "Warning: Kernel filter failed: %s\n", 1028478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project pcap_strerror(errno)); 1029478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1030478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1031478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1032478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1033478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1034478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * If we're not using the kernel filter, get rid of any kernel 1035478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * filter that might've been there before, e.g. because the 1036478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * previous filter could work in the kernel, or because some other 1037478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * code attached a filter to the socket by some means other than 1038478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * calling "pcap_setfilter()". Otherwise, the kernel filter may 1039478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * filter out packets that would pass the new userland filter. 1040478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1041478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (!handle->md.use_bpf) 1042478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project reset_kernel_filter(handle); 1043478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1044478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1045478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Free up the copy of the filter that was made by "fix_program()". 1046478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1047478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (fcode.filter != NULL) 1048478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project free(fcode.filter); 1049478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1050478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (err == -2) 1051478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Fatal error */ 1052478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -1; 1053478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif /* SO_ATTACH_FILTER */ 1054478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1055478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return 0; 1056478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project} 1057478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1058478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 1059478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Set direction flag: Which packets do we accept on a forwarding 1060478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * single device? IN, OUT or both? 1061478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1062478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int 1063478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectpcap_setdirection_linux(pcap_t *handle, pcap_direction_t d) 1064478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project{ 1065478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef HAVE_PF_PACKET_SOCKETS 1066478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (!handle->md.sock_packet) { 1067478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->direction = d; 1068478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return 0; 1069478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1070478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 1071478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1072478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * We're not using PF_PACKET sockets, so we can't determine 1073478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the direction of the packet. 1074478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1075478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(handle->errbuf, sizeof(handle->errbuf), 1076478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "Setting direction is not supported on SOCK_PACKET sockets"); 1077478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -1; 1078478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project} 1079478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1080478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 1081478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Linux uses the ARP hardware type to identify the type of an 1082478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * interface. pcap uses the DLT_xxx constants for this. This 1083478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * function takes a pointer to a "pcap_t", and an ARPHRD_xxx 1084478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * constant, as arguments, and sets "handle->linktype" to the 1085478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * appropriate DLT_XXX constant and sets "handle->offset" to 1086478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the appropriate value (to make "handle->offset" plus link-layer 1087478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * header length be a multiple of 4, so that the link-layer payload 1088478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * will be aligned on a 4-byte boundary when capturing packets). 1089478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * (If the offset isn't set here, it'll be 0; add code as appropriate 1090478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * for cases where it shouldn't be 0.) 1091478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 1092478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * If "cooked_ok" is non-zero, we can use DLT_LINUX_SLL and capture 1093478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * in cooked mode; otherwise, we can't use cooked mode, so we have 1094478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * to pick some type that works in raw mode, or fail. 1095478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 1096478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Sets the link type to -1 if unable to map the type. 1097478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1098478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic void map_arphrd_to_dlt(pcap_t *handle, int arptype, int cooked_ok) 1099478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project{ 1100478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project switch (arptype) { 1101478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1102478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_ETHER: 1103478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1104478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * This is (presumably) a real Ethernet capture; give it a 1105478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * link-layer-type list with DLT_EN10MB and DLT_DOCSIS, so 1106478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * that an application can let you choose it, in case you're 1107478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * capturing DOCSIS traffic that a Cisco Cable Modem 1108478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Termination System is putting out onto an Ethernet (it 1109478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * doesn't put an Ethernet header onto the wire, it puts raw 1110478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * DOCSIS frames out on the wire inside the low-level 1111478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Ethernet framing). 1112478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 1113478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * XXX - are there any sorts of "fake Ethernet" that have 1114478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * ARPHRD_ETHER but that *shouldn't offer DLT_DOCSIS as 1115478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * a Cisco CMTS won't put traffic onto it or get traffic 1116478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * bridged onto it? ISDN is handled in "live_open_new()", 1117478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * as we fall back on cooked mode there; are there any 1118478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * others? 1119478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1120478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->dlt_list = (u_int *) malloc(sizeof(u_int) * 2); 1121478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1122478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * If that fails, just leave the list empty. 1123478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1124478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->dlt_list != NULL) { 1125478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->dlt_list[0] = DLT_EN10MB; 1126478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->dlt_list[1] = DLT_DOCSIS; 1127478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->dlt_count = 2; 1128478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1129478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* FALLTHROUGH */ 1130478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1131478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_METRICOM: 1132478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_LOOPBACK: 1133478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_EN10MB; 1134478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->offset = 2; 1135478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1136478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1137478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_EETHER: 1138478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_EN3MB; 1139478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1140478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1141478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_AX25: 1142478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_AX25; 1143478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1144478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1145478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_PRONET: 1146478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_PRONET; 1147478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1148478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1149478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_CHAOS: 1150478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_CHAOS; 1151478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1152478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1153478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifndef ARPHRD_IEEE802_TR 1154478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#define ARPHRD_IEEE802_TR 800 /* From Linux 2.4 */ 1155478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 1156478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_IEEE802_TR: 1157478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_IEEE802: 1158478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_IEEE802; 1159478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->offset = 2; 1160478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1161478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1162478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_ARCNET: 1163478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_ARCNET_LINUX; 1164478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1165478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1166478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifndef ARPHRD_FDDI /* From Linux 2.2.13 */ 1167478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#define ARPHRD_FDDI 774 1168478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 1169478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_FDDI: 1170478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_FDDI; 1171478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->offset = 3; 1172478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1173478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1174478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifndef ARPHRD_ATM /* FIXME: How to #include this? */ 1175478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#define ARPHRD_ATM 19 1176478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 1177478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_ATM: 1178478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1179478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * The Classical IP implementation in ATM for Linux 1180478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * supports both what RFC 1483 calls "LLC Encapsulation", 1181478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * in which each packet has an LLC header, possibly 1182478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * with a SNAP header as well, prepended to it, and 1183478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * what RFC 1483 calls "VC Based Multiplexing", in which 1184478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * different virtual circuits carry different network 1185478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * layer protocols, and no header is prepended to packets. 1186478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 1187478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * They both have an ARPHRD_ type of ARPHRD_ATM, so 1188478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * you can't use the ARPHRD_ type to find out whether 1189478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * captured packets will have an LLC header, and, 1190478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * while there's a socket ioctl to *set* the encapsulation 1191478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * type, there's no ioctl to *get* the encapsulation type. 1192478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 1193478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * This means that 1194478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 1195478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * programs that dissect Linux Classical IP frames 1196478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * would have to check for an LLC header and, 1197478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * depending on whether they see one or not, dissect 1198478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the frame as LLC-encapsulated or as raw IP (I 1199478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * don't know whether there's any traffic other than 1200478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * IP that would show up on the socket, or whether 1201478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * there's any support for IPv6 in the Linux 1202478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Classical IP code); 1203478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 1204478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * filter expressions would have to compile into 1205478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * code that checks for an LLC header and does 1206478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the right thing. 1207478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 1208478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Both of those are a nuisance - and, at least on systems 1209478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * that support PF_PACKET sockets, we don't have to put 1210478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * up with those nuisances; instead, we can just capture 1211478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * in cooked mode. That's what we'll do, if we can. 1212478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Otherwise, we'll just fail. 1213478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1214478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (cooked_ok) 1215478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_LINUX_SLL; 1216478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project else 1217478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = -1; 1218478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1219478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1220478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifndef ARPHRD_IEEE80211 /* From Linux 2.4.6 */ 1221478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#define ARPHRD_IEEE80211 801 1222478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 1223478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_IEEE80211: 1224478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_IEEE802_11; 1225478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1226478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1227478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifndef ARPHRD_IEEE80211_PRISM /* From Linux 2.4.18 */ 1228478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#define ARPHRD_IEEE80211_PRISM 802 1229478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 1230478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_IEEE80211_PRISM: 1231478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_PRISM_HEADER; 1232478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1233478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1234478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifndef ARPHRD_IEEE80211_RADIOTAP /* new */ 1235478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#define ARPHRD_IEEE80211_RADIOTAP 803 1236478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 1237478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_IEEE80211_RADIOTAP: 1238478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_IEEE802_11_RADIO; 1239478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1240478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1241478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_PPP: 1242478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1243478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Some PPP code in the kernel supplies no link-layer 1244478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * header whatsoever to PF_PACKET sockets; other PPP 1245478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * code supplies PPP link-layer headers ("syncppp.c"); 1246478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * some PPP code might supply random link-layer 1247478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * headers (PPP over ISDN - there's code in Ethereal, 1248478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * for example, to cope with PPP-over-ISDN captures 1249478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * with which the Ethereal developers have had to cope, 1250478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * heuristically trying to determine which of the 1251478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * oddball link-layer headers particular packets have). 1252478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 1253478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * As such, we just punt, and run all PPP interfaces 1254478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * in cooked mode, if we can; otherwise, we just treat 1255478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * it as DLT_RAW, for now - if somebody needs to capture, 1256478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * on a 2.0[.x] kernel, on PPP devices that supply a 1257478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * link-layer header, they'll have to add code here to 1258478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * map to the appropriate DLT_ type (possibly adding a 1259478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * new DLT_ type, if necessary). 1260478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1261478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (cooked_ok) 1262478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_LINUX_SLL; 1263478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project else { 1264478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1265478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * XXX - handle ISDN types here? We can't fall 1266478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * back on cooked sockets, so we'd have to 1267478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * figure out from the device name what type of 1268478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * link-layer encapsulation it's using, and map 1269478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * that to an appropriate DLT_ value, meaning 1270478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * we'd map "isdnN" devices to DLT_RAW (they 1271478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * supply raw IP packets with no link-layer 1272478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * header) and "isdY" devices to a new DLT_I4L_IP 1273478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * type that has only an Ethernet packet type as 1274478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * a link-layer header. 1275478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 1276478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * But sometimes we seem to get random crap 1277478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * in the link-layer header when capturing on 1278478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * ISDN devices.... 1279478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1280478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_RAW; 1281478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1282478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1283478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1284478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifndef ARPHRD_CISCO 1285478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#define ARPHRD_CISCO 513 /* previously ARPHRD_HDLC */ 1286478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 1287478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_CISCO: 1288478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_C_HDLC; 1289478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1290478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1291478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Not sure if this is correct for all tunnels, but it 1292478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * works for CIPE */ 1293478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_TUNNEL: 1294478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifndef ARPHRD_SIT 1295478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#define ARPHRD_SIT 776 /* From Linux 2.2.13 */ 1296478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 1297478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_SIT: 1298478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_CSLIP: 1299478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_SLIP6: 1300478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_CSLIP6: 1301478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_ADAPT: 1302478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_SLIP: 1303478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifndef ARPHRD_RAWHDLC 1304478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#define ARPHRD_RAWHDLC 518 1305478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 1306478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_RAWHDLC: 1307478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifndef ARPHRD_DLCI 1308478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#define ARPHRD_DLCI 15 1309478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 1310478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_DLCI: 1311478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1312478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * XXX - should some of those be mapped to DLT_LINUX_SLL 1313478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * instead? Should we just map all of them to DLT_LINUX_SLL? 1314478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1315478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_RAW; 1316478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1317478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1318478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifndef ARPHRD_FRAD 1319478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#define ARPHRD_FRAD 770 1320478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 1321478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_FRAD: 1322478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_FRELAY; 1323478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1324478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1325478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_LOCALTLK: 1326478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_LTALK; 1327478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1328478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1329478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifndef ARPHRD_FCPP 1330478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#define ARPHRD_FCPP 784 1331478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 1332478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_FCPP: 1333478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifndef ARPHRD_FCAL 1334478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#define ARPHRD_FCAL 785 1335478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 1336478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_FCAL: 1337478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifndef ARPHRD_FCPL 1338478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#define ARPHRD_FCPL 786 1339478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 1340478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_FCPL: 1341478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifndef ARPHRD_FCFABRIC 1342478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#define ARPHRD_FCFABRIC 787 1343478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 1344478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_FCFABRIC: 1345478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1346478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * We assume that those all mean RFC 2625 IP-over- 1347478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Fibre Channel, with the RFC 2625 header at 1348478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the beginning of the packet. 1349478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1350478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_IP_OVER_FC; 1351478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1352478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1353478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifndef ARPHRD_IRDA 1354478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#define ARPHRD_IRDA 783 1355478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 1356478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_IRDA: 1357478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Don't expect IP packet out of this interfaces... */ 1358478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_LINUX_IRDA; 1359478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* We need to save packet direction for IrDA decoding, 1360478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * so let's use "Linux-cooked" mode. Jean II */ 1361478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project //handle->md.cooked = 1; 1362478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1363478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1364478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* ARPHRD_LAPD is unofficial and randomly allocated, if reallocation 1365478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * is needed, please report it to <daniele@orlandi.com> */ 1366478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifndef ARPHRD_LAPD 1367478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#define ARPHRD_LAPD 8445 1368478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 1369478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case ARPHRD_LAPD: 1370478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Don't expect IP packet out of this interfaces... */ 1371478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_LINUX_LAPD; 1372478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1373478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1374478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project default: 1375478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = -1; 1376478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1377478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1378478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project} 1379478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1380478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* ===== Functions to interface to the newer kernels ================== */ 1381478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1382478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 1383478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Try to open a packet socket using the new kernel interface. 1384478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Returns 0 on failure. 1385478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * FIXME: 0 uses to mean success (Sebastian) 1386478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1387478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int 1388478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectlive_open_new(pcap_t *handle, const char *device, int promisc, 1389478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project int to_ms, char *ebuf) 1390478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project{ 1391478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef HAVE_PF_PACKET_SOCKETS 1392478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project int sock_fd = -1, arptype; 1393478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project int err; 1394478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project int fatal_err = 0; 1395478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project struct packet_mreq mr; 1396478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1397478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* One shot loop used for error handling - bail out with break */ 1398478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1399478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project do { 1400478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1401478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Open a socket with protocol family packet. If a device is 1402478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * given we try to open it in raw mode otherwise we use 1403478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the cooked interface. 1404478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1405478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project sock_fd = device ? 1406478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project socket(PF_PACKET, SOCK_RAW, htons(ETH_P_ALL)) 1407478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project : socket(PF_PACKET, SOCK_DGRAM, htons(ETH_P_ALL)); 1408478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1409478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (sock_fd == -1) { 1410478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(ebuf, PCAP_ERRBUF_SIZE, "socket: %s", 1411478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project pcap_strerror(errno) ); 1412478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1413478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1414478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1415478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* It seems the kernel supports the new interface. */ 1416478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->md.sock_packet = 0; 1417478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1418478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1419478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Get the interface index of the loopback device. 1420478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * If the attempt fails, don't fail, just set the 1421478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * "md.lo_ifindex" to -1. 1422478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 1423478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * XXX - can there be more than one device that loops 1424478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * packets back, i.e. devices other than "lo"? If so, 1425478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * we'd need to find them all, and have an array of 1426478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * indices for them, and check all of them in 1427478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * "pcap_read_packet()". 1428478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1429478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->md.lo_ifindex = iface_get_id(sock_fd, "lo", ebuf); 1430478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1431478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1432478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Default value for offset to align link-layer payload 1433478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * on a 4-byte boundary. 1434478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1435478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->offset = 0; 1436478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1437478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1438478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * What kind of frames do we have to deal with? Fall back 1439478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * to cooked mode if we have an unknown interface type. 1440478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1441478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1442478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (device) { 1443478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Assume for now we don't need cooked mode. */ 1444478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->md.cooked = 0; 1445478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1446478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project arptype = iface_get_arptype(sock_fd, device, ebuf); 1447478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (arptype == -1) { 1448478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project fatal_err = 1; 1449478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1450478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1451478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project map_arphrd_to_dlt(handle, arptype, 1); 1452478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->linktype == -1 || 1453478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype == DLT_LINUX_SLL || 1454478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype == DLT_LINUX_IRDA || 1455478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype == DLT_LINUX_LAPD || 1456478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project (handle->linktype == DLT_EN10MB && 1457478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project (strncmp("isdn", device, 4) == 0 || 1458478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project strncmp("isdY", device, 4) == 0))) { 1459478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1460478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Unknown interface type (-1), or a 1461478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * device we explicitly chose to run 1462478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * in cooked mode (e.g., PPP devices), 1463478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * or an ISDN device (whose link-layer 1464478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * type we can only determine by using 1465478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * APIs that may be different on different 1466478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * kernels) - reopen in cooked mode. 1467478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1468478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (close(sock_fd) == -1) { 1469478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(ebuf, PCAP_ERRBUF_SIZE, 1470478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "close: %s", pcap_strerror(errno)); 1471478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1472478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1473478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project sock_fd = socket(PF_PACKET, SOCK_DGRAM, 1474478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project htons(ETH_P_ALL)); 1475478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (sock_fd == -1) { 1476478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(ebuf, PCAP_ERRBUF_SIZE, 1477478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "socket: %s", pcap_strerror(errno)); 1478478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1479478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1480478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->md.cooked = 1; 1481478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1482478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1483478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Get rid of any link-layer type list 1484478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * we allocated - this only supports cooked 1485478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * capture. 1486478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1487478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->dlt_list != NULL) { 1488478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project free(handle->dlt_list); 1489478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->dlt_list = NULL; 1490478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->dlt_count = 0; 1491478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1492478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1493478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->linktype == -1) { 1494478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1495478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Warn that we're falling back on 1496478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * cooked mode; we may want to 1497478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * update "map_arphrd_to_dlt()" 1498478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * to handle the new type. 1499478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1500478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(ebuf, PCAP_ERRBUF_SIZE, 1501478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "arptype %d not " 1502478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "supported by libpcap - " 1503478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "falling back to cooked " 1504478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "socket", 1505478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project arptype); 1506478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1507478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* IrDA capture is not a real "cooked" capture, 1508478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * it's IrLAP frames, not IP packets. */ 1509478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->linktype != DLT_LINUX_IRDA && 1510478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype != DLT_LINUX_LAPD) 1511478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_LINUX_SLL; 1512478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1513478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1514478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->md.ifindex = iface_get_id(sock_fd, device, ebuf); 1515478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->md.ifindex == -1) 1516478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1517478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1518478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if ((err = iface_bind(sock_fd, handle->md.ifindex, 1519478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project ebuf)) < 0) { 1520478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (err == -2) 1521478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project fatal_err = 1; 1522478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1523478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1524478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } else { 1525478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1526478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * This is cooked mode. 1527478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1528478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->md.cooked = 1; 1529478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->linktype = DLT_LINUX_SLL; 1530478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1531478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1532478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * We're not bound to a device. 1533478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * XXX - true? Or true only if we're using 1534478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the "any" device? 1535478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * For now, we're using this as an indication 1536478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * that we can't transmit; stop doing that only 1537478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * if we figure out how to transmit in cooked 1538478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * mode. 1539478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1540478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->md.ifindex = -1; 1541478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1542478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1543478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1544478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Select promiscuous mode on if "promisc" is set. 1545478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 1546478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Do not turn allmulti mode on if we don't select 1547478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * promiscuous mode - on some devices (e.g., Orinoco 1548478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * wireless interfaces), allmulti mode isn't supported 1549478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * and the driver implements it by turning promiscuous 1550478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * mode on, and that screws up the operation of the 1551478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * card as a normal networking interface, and on no 1552478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * other platform I know of does starting a non- 1553478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * promiscuous capture affect which multicast packets 1554478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * are received by the interface. 1555478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1556478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1557478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1558478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Hmm, how can we set promiscuous mode on all interfaces? 1559478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * I am not sure if that is possible at all. 1560478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1561478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1562478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (device && promisc) { 1563478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project memset(&mr, 0, sizeof(mr)); 1564478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project mr.mr_ifindex = handle->md.ifindex; 1565478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project mr.mr_type = PACKET_MR_PROMISC; 1566478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (setsockopt(sock_fd, SOL_PACKET, 1567478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project PACKET_ADD_MEMBERSHIP, &mr, sizeof(mr)) == -1) 1568478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project { 1569478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(ebuf, PCAP_ERRBUF_SIZE, 1570478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "setsockopt: %s", pcap_strerror(errno)); 1571478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1572478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1573478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1574478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1575478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Save the socket FD in the pcap structure */ 1576478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1577478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->fd = sock_fd; 1578478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1579478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return 1; 1580478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1581478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } while(0); 1582478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1583478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (sock_fd != -1) 1584478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project close(sock_fd); 1585478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1586478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (fatal_err) { 1587478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1588478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Get rid of any link-layer type list we allocated. 1589478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1590478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->dlt_list != NULL) 1591478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project free(handle->dlt_list); 1592478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -2; 1593478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } else 1594478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return 0; 1595478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#else 1596478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project strncpy(ebuf, 1597478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "New packet capturing interface not supported by build " 1598478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "environment", PCAP_ERRBUF_SIZE); 1599478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return 0; 1600478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 1601478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project} 1602478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1603478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef HAVE_PF_PACKET_SOCKETS 1604478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 1605478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Return the index of the given device name. Fill ebuf and return 1606478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * -1 on failure. 1607478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1608478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int 1609478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectiface_get_id(int fd, const char *device, char *ebuf) 1610478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project{ 1611478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project struct ifreq ifr; 1612478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1613478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project memset(&ifr, 0, sizeof(ifr)); 1614478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project strncpy(ifr.ifr_name, device, sizeof(ifr.ifr_name)); 1615478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1616478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (ioctl(fd, SIOCGIFINDEX, &ifr) == -1) { 1617478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(ebuf, PCAP_ERRBUF_SIZE, 1618478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "SIOCGIFINDEX: %s", pcap_strerror(errno)); 1619478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -1; 1620478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1621478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1622478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return ifr.ifr_ifindex; 1623478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project} 1624478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1625478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 1626478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Bind the socket associated with FD to the given device. 1627478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1628478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int 1629478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectiface_bind(int fd, int ifindex, char *ebuf) 1630478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project{ 1631478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project struct sockaddr_ll sll; 1632478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project int err; 1633478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project socklen_t errlen = sizeof(err); 1634478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1635478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project memset(&sll, 0, sizeof(sll)); 1636478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project sll.sll_family = AF_PACKET; 1637478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project sll.sll_ifindex = ifindex; 1638478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project sll.sll_protocol = htons(ETH_P_ALL); 1639478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1640478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (bind(fd, (struct sockaddr *) &sll, sizeof(sll)) == -1) { 1641478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(ebuf, PCAP_ERRBUF_SIZE, 1642478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "bind: %s", pcap_strerror(errno)); 1643478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -1; 1644478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1645478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1646478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Any pending errors, e.g., network is down? */ 1647478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1648478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (getsockopt(fd, SOL_SOCKET, SO_ERROR, &err, &errlen) == -1) { 1649478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(ebuf, PCAP_ERRBUF_SIZE, 1650478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "getsockopt: %s", pcap_strerror(errno)); 1651478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -2; 1652478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1653478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1654478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (err > 0) { 1655478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(ebuf, PCAP_ERRBUF_SIZE, 1656478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "bind: %s", pcap_strerror(err)); 1657478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -2; 1658478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1659478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1660478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return 0; 1661478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project} 1662478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1663478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 1664478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1665478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1666478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* ===== Functions to interface to the older kernels ================== */ 1667478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1668478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 1669478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * With older kernels promiscuous mode is kind of interesting because we 1670478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * have to reset the interface before exiting. The problem can't really 1671478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * be solved without some daemon taking care of managing usage counts. 1672478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * If we put the interface into promiscuous mode, we set a flag indicating 1673478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * that we must take it out of that mode when the interface is closed, 1674478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * and, when closing the interface, if that flag is set we take it out 1675478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * of promiscuous mode. 1676478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1677478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1678478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 1679478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * List of pcaps for which we turned promiscuous mode on by hand. 1680478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * If there are any such pcaps, we arrange to call "pcap_close_all()" 1681478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * when we exit, and have it close all of them to turn promiscuous mode 1682478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * off. 1683478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1684478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic struct pcap *pcaps_to_close; 1685478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1686478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 1687478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * TRUE if we've already called "atexit()" to cause "pcap_close_all()" to 1688478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * be called on exit. 1689478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1690478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int did_atexit; 1691478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1692478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic void pcap_close_all(void) 1693478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project{ 1694478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project struct pcap *handle; 1695478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1696478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project while ((handle = pcaps_to_close) != NULL) 1697478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project pcap_close(handle); 1698478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project} 1699478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1700478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic void pcap_close_linux( pcap_t *handle ) 1701478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project{ 1702478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project struct pcap *p, *prevp; 1703478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project struct ifreq ifr; 1704478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1705478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->md.clear_promisc) { 1706478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1707478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * We put the interface into promiscuous mode; take 1708478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * it out of promiscuous mode. 1709478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 1710478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * XXX - if somebody else wants it in promiscuous mode, 1711478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * this code cannot know that, so it'll take it out 1712478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * of promiscuous mode. That's not fixable in 2.0[.x] 1713478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * kernels. 1714478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1715478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project memset(&ifr, 0, sizeof(ifr)); 1716478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project strncpy(ifr.ifr_name, handle->md.device, sizeof(ifr.ifr_name)); 1717478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (ioctl(handle->fd, SIOCGIFFLAGS, &ifr) == -1) { 1718478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project fprintf(stderr, 1719478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "Can't restore interface flags (SIOCGIFFLAGS failed: %s).\n" 1720478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "Please adjust manually.\n" 1721478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "Hint: This can't happen with Linux >= 2.2.0.\n", 1722478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project strerror(errno)); 1723478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } else { 1724478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (ifr.ifr_flags & IFF_PROMISC) { 1725478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1726478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Promiscuous mode is currently on; turn it 1727478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * off. 1728478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1729478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project ifr.ifr_flags &= ~IFF_PROMISC; 1730478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (ioctl(handle->fd, SIOCSIFFLAGS, &ifr) == -1) { 1731478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project fprintf(stderr, 1732478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "Can't restore interface flags (SIOCSIFFLAGS failed: %s).\n" 1733478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "Please adjust manually.\n" 1734478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "Hint: This can't happen with Linux >= 2.2.0.\n", 1735478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project strerror(errno)); 1736478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1737478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1738478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1739478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1740478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1741478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Take this pcap out of the list of pcaps for which we 1742478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * have to take the interface out of promiscuous mode. 1743478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1744478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project for (p = pcaps_to_close, prevp = NULL; p != NULL; 1745478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project prevp = p, p = p->md.next) { 1746478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (p == handle) { 1747478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1748478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Found it. Remove it from the list. 1749478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1750478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (prevp == NULL) { 1751478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1752478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * It was at the head of the list. 1753478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1754478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project pcaps_to_close = p->md.next; 1755478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } else { 1756478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1757478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * It was in the middle of the list. 1758478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1759478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project prevp->md.next = p->md.next; 1760478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1761478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1762478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1763478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1764478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1765478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1766478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->md.device != NULL) 1767478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project free(handle->md.device); 1768478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->md.device = NULL; 1769478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project pcap_close_common(handle); 1770478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project} 1771478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1772478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 1773478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Try to open a packet socket using the old kernel interface. 1774478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Returns 0 on failure. 1775478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * FIXME: 0 uses to mean success (Sebastian) 1776478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1777478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int 1778478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectlive_open_old(pcap_t *handle, const char *device, int promisc, 1779478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project int to_ms, char *ebuf) 1780478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project{ 1781478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project int arptype; 1782478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project struct ifreq ifr; 1783478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1784478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project do { 1785478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Open the socket */ 1786478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1787478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->fd = socket(PF_INET, SOCK_PACKET, htons(ETH_P_ALL)); 1788478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->fd == -1) { 1789478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(ebuf, PCAP_ERRBUF_SIZE, 1790478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "socket: %s", pcap_strerror(errno)); 1791478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1792478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1793478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1794478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* It worked - we are using the old interface */ 1795478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->md.sock_packet = 1; 1796478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1797478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* ...which means we get the link-layer header. */ 1798478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->md.cooked = 0; 1799478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1800478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Bind to the given device */ 1801478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1802478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (!device) { 1803478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project strncpy(ebuf, "pcap_open_live: The \"any\" device isn't supported on 2.0[.x]-kernel systems", 1804478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project PCAP_ERRBUF_SIZE); 1805478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1806478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1807478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (iface_bind_old(handle->fd, device, ebuf) == -1) 1808478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1809478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1810478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1811478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Try to get the link-layer type. 1812478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1813478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project arptype = iface_get_arptype(handle->fd, device, ebuf); 1814478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (arptype == -1) 1815478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1816478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1817478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1818478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Try to find the DLT_ type corresponding to that 1819478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * link-layer type. 1820478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1821478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project map_arphrd_to_dlt(handle, arptype, 0); 1822478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->linktype == -1) { 1823478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(ebuf, PCAP_ERRBUF_SIZE, 1824478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "unknown arptype %d", arptype); 1825478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1826478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1827478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1828478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Go to promisc mode if requested */ 1829478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1830478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (promisc) { 1831478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project memset(&ifr, 0, sizeof(ifr)); 1832478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project strncpy(ifr.ifr_name, device, sizeof(ifr.ifr_name)); 1833478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (ioctl(handle->fd, SIOCGIFFLAGS, &ifr) == -1) { 1834478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(ebuf, PCAP_ERRBUF_SIZE, 1835478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "SIOCGIFFLAGS: %s", pcap_strerror(errno)); 1836478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1837478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1838478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if ((ifr.ifr_flags & IFF_PROMISC) == 0) { 1839478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1840478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Promiscuous mode isn't currently on, 1841478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * so turn it on, and remember that 1842478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * we should turn it off when the 1843478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * pcap_t is closed. 1844478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1845478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1846478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1847478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * If we haven't already done so, arrange 1848478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * to have "pcap_close_all()" called when 1849478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * we exit. 1850478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1851478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (!did_atexit) { 1852478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (atexit(pcap_close_all) == -1) { 1853478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1854478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * "atexit()" failed; don't 1855478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * put the interface in 1856478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * promiscuous mode, just 1857478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * give up. 1858478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1859478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project strncpy(ebuf, "atexit failed", 1860478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project PCAP_ERRBUF_SIZE); 1861478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1862478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1863478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project did_atexit = 1; 1864478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1865478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1866478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project ifr.ifr_flags |= IFF_PROMISC; 1867478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (ioctl(handle->fd, SIOCSIFFLAGS, &ifr) == -1) { 1868478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(ebuf, PCAP_ERRBUF_SIZE, 1869478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "SIOCSIFFLAGS: %s", 1870478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project pcap_strerror(errno)); 1871478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 1872478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1873478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->md.clear_promisc = 1; 1874478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1875478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1876478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Add this to the list of pcaps 1877478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * to close when we exit. 1878478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1879478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->md.next = pcaps_to_close; 1880478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project pcaps_to_close = handle; 1881478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1882478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1883478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1884478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1885478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Default value for offset to align link-layer payload 1886478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * on a 4-byte boundary. 1887478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1888478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project handle->offset = 0; 1889478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1890478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return 1; 1891478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1892478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } while (0); 1893478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1894478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project pcap_close_linux(handle); 1895478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return 0; 1896478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project} 1897478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1898478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 1899478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Bind the socket associated with FD to the given device using the 1900478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * interface of the old kernels. 1901478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1902478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int 1903478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectiface_bind_old(int fd, const char *device, char *ebuf) 1904478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project{ 1905478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project struct sockaddr saddr; 1906478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project int err; 1907478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project socklen_t errlen = sizeof(err); 1908478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1909478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project memset(&saddr, 0, sizeof(saddr)); 1910478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project strncpy(saddr.sa_data, device, sizeof(saddr.sa_data)); 1911478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (bind(fd, &saddr, sizeof(saddr)) == -1) { 1912478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(ebuf, PCAP_ERRBUF_SIZE, 1913478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "bind: %s", pcap_strerror(errno)); 1914478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -1; 1915478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1916478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1917478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Any pending errors, e.g., network is down? */ 1918478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1919478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (getsockopt(fd, SOL_SOCKET, SO_ERROR, &err, &errlen) == -1) { 1920478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(ebuf, PCAP_ERRBUF_SIZE, 1921478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "getsockopt: %s", pcap_strerror(errno)); 1922478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -1; 1923478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1924478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1925478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (err > 0) { 1926478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(ebuf, PCAP_ERRBUF_SIZE, 1927478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "bind: %s", pcap_strerror(err)); 1928478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -1; 1929478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1930478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1931478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return 0; 1932478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project} 1933478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1934478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1935478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* ===== System calls available on all supported kernels ============== */ 1936478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1937478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 1938478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Query the kernel for the MTU of the given interface. 1939478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1940478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int 1941478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectiface_get_mtu(int fd, const char *device, char *ebuf) 1942478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project{ 1943478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project struct ifreq ifr; 1944478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1945478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (!device) 1946478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return BIGGER_THAN_ALL_MTUS; 1947478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1948478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project memset(&ifr, 0, sizeof(ifr)); 1949478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project strncpy(ifr.ifr_name, device, sizeof(ifr.ifr_name)); 1950478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1951478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (ioctl(fd, SIOCGIFMTU, &ifr) == -1) { 1952478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(ebuf, PCAP_ERRBUF_SIZE, 1953478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "SIOCGIFMTU: %s", pcap_strerror(errno)); 1954478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -1; 1955478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1956478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1957478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return ifr.ifr_mtu; 1958478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project} 1959478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1960478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project/* 1961478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Get the hardware type of the given interface as ARPHRD_xxx constant. 1962478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1963478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int 1964478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectiface_get_arptype(int fd, const char *device, char *ebuf) 1965478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project{ 1966478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project struct ifreq ifr; 1967478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1968478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project memset(&ifr, 0, sizeof(ifr)); 1969478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project strncpy(ifr.ifr_name, device, sizeof(ifr.ifr_name)); 1970478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1971478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (ioctl(fd, SIOCGIFHWADDR, &ifr) == -1) { 1972478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(ebuf, PCAP_ERRBUF_SIZE, 1973478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "SIOCGIFHWADDR: %s", pcap_strerror(errno)); 1974478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -1; 1975478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 1976478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1977478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return ifr.ifr_hwaddr.sa_family; 1978478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project} 1979478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1980478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#ifdef SO_ATTACH_FILTER 1981478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int 1982478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectfix_program(pcap_t *handle, struct sock_fprog *fcode) 1983478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project{ 1984478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project size_t prog_size; 1985478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project register int i; 1986478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project register struct bpf_insn *p; 1987478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project struct bpf_insn *f; 1988478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project int len; 1989478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 1990478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 1991478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Make a copy of the filter, and modify that copy if 1992478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * necessary. 1993478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 1994478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project prog_size = sizeof(*handle->fcode.bf_insns) * handle->fcode.bf_len; 1995478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project len = handle->fcode.bf_len; 1996478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project f = (struct bpf_insn *)malloc(prog_size); 1997478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (f == NULL) { 1998478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(handle->errbuf, sizeof(handle->errbuf), 1999478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "malloc: %s", pcap_strerror(errno)); 2000478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -1; 2001478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 2002478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project memcpy(f, handle->fcode.bf_insns, prog_size); 2003478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project fcode->len = len; 2004478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project fcode->filter = (struct sock_filter *) f; 2005478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 2006478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project for (i = 0; i < len; ++i) { 2007478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project p = &f[i]; 2008478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 2009478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * What type of instruction is this? 2010478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 2011478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project switch (BPF_CLASS(p->code)) { 2012478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 2013478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case BPF_RET: 2014478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 2015478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * It's a return instruction; is the snapshot 2016478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * length a constant, rather than the contents 2017478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * of the accumulator? 2018478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 2019478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (BPF_MODE(p->code) == BPF_K) { 2020478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 2021478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Yes - if the value to be returned, 2022478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * i.e. the snapshot length, is anything 2023478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * other than 0, make it 65535, so that 2024478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the packet is truncated by "recvfrom()", 2025478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * not by the filter. 2026478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 2027478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * XXX - there's nothing we can easily do 2028478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * if it's getting the value from the 2029478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * accumulator; we'd have to insert 2030478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * code to force non-zero values to be 2031478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 65535. 2032478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 2033478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (p->k != 0) 2034478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project p->k = 65535; 2035478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 2036478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 2037478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 2038478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case BPF_LD: 2039478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case BPF_LDX: 2040478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 2041478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * It's a load instruction; is it loading 2042478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * from the packet? 2043478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 2044478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project switch (BPF_MODE(p->code)) { 2045478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 2046478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case BPF_ABS: 2047478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case BPF_IND: 2048478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project case BPF_MSH: 2049478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 2050478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Yes; are we in cooked mode? 2051478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 2052478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (handle->md.cooked) { 2053478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 2054478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Yes, so we need to fix this 2055478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * instruction. 2056478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 2057478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (fix_offset(p) < 0) { 2058478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 2059478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * We failed to do so. 2060478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Return 0, so our caller 2061478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * knows to punt to userland. 2062478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 2063478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return 0; 2064478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 2065478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 2066478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 2067478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 2068478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project break; 2069478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 2070478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 2071478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return 1; /* we succeeded */ 2072478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project} 2073478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 2074478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int 2075478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectfix_offset(struct bpf_insn *p) 2076478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project{ 2077478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 2078478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * What's the offset? 2079478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 2080478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (p->k >= SLL_HDR_LEN) { 2081478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 2082478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * It's within the link-layer payload; that starts at an 2083478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * offset of 0, as far as the kernel packet filter is 2084478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * concerned, so subtract the length of the link-layer 2085478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * header. 2086478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 2087478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project p->k -= SLL_HDR_LEN; 2088478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } else if (p->k == 14) { 2089478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 2090478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * It's the protocol field; map it to the special magic 2091478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * kernel offset for that field. 2092478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 2093478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project p->k = SKF_AD_OFF + SKF_AD_PROTOCOL; 2094478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } else { 2095478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 2096478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * It's within the header, but it's not one of those 2097478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * fields; we can't do that in the kernel, so punt 2098478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * to userland. 2099478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 2100478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -1; 2101478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 2102478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return 0; 2103478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project} 2104478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 2105478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int 2106478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectset_kernel_filter(pcap_t *handle, struct sock_fprog *fcode) 2107478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project{ 2108478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project int total_filter_on = 0; 2109478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project int save_mode; 2110478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project int ret; 2111478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project int save_errno; 2112478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 2113478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 2114478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * The socket filter code doesn't discard all packets queued 2115478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * up on the socket when the filter is changed; this means 2116478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * that packets that don't match the new filter may show up 2117478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * after the new filter is put onto the socket, if those 2118478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * packets haven't yet been read. 2119478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 2120478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * This means, for example, that if you do a tcpdump capture 2121478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * with a filter, the first few packets in the capture might 2122478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * be packets that wouldn't have passed the filter. 2123478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 2124478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * We therefore discard all packets queued up on the socket 2125478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * when setting a kernel filter. (This isn't an issue for 2126478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * userland filters, as the userland filtering is done after 2127478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * packets are queued up.) 2128478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 2129478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * To flush those packets, we put the socket in read-only mode, 2130478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * and read packets from the socket until there are no more to 2131478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * read. 2132478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 2133478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * In order to keep that from being an infinite loop - i.e., 2134478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * to keep more packets from arriving while we're draining 2135478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the queue - we put the "total filter", which is a filter 2136478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * that rejects all packets, onto the socket before draining 2137478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the queue. 2138478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 2139478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * This code deliberately ignores any errors, so that you may 2140478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * get bogus packets if an error occurs, rather than having 2141478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * the filtering done in userland even if it could have been 2142478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * done in the kernel. 2143478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 2144478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (setsockopt(handle->fd, SOL_SOCKET, SO_ATTACH_FILTER, 2145478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project &total_fcode, sizeof(total_fcode)) == 0) { 2146478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project char drain[1]; 2147478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 2148478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 2149478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Note that we've put the total filter onto the socket. 2150478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 2151478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project total_filter_on = 1; 2152478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 2153478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 2154478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Save the socket's current mode, and put it in 2155478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * non-blocking mode; we drain it by reading packets 2156478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * until we get an error (which is normally a 2157478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * "nothing more to be read" error). 2158478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 2159478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project save_mode = fcntl(handle->fd, F_GETFL, 0); 2160478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (save_mode != -1 && 2161478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project fcntl(handle->fd, F_SETFL, save_mode | O_NONBLOCK) >= 0) { 2162478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project while (recv(handle->fd, &drain, sizeof drain, 2163478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project MSG_TRUNC) >= 0) 2164478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project ; 2165478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project save_errno = errno; 2166478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project fcntl(handle->fd, F_SETFL, save_mode); 2167478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (save_errno != EAGAIN) { 2168478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* Fatal error */ 2169478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project reset_kernel_filter(handle); 2170478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project snprintf(handle->errbuf, sizeof(handle->errbuf), 2171478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project "recv: %s", pcap_strerror(save_errno)); 2172478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return -2; 2173478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 2174478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 2175478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 2176478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 2177478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 2178478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Now attach the new filter. 2179478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 2180478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project ret = setsockopt(handle->fd, SOL_SOCKET, SO_ATTACH_FILTER, 2181478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project fcode, sizeof(*fcode)); 2182478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project if (ret == -1 && total_filter_on) { 2183478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 2184478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * Well, we couldn't set that filter on the socket, 2185478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * but we could set the total filter on the socket. 2186478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * 2187478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * This could, for example, mean that the filter was 2188478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * too big to put into the kernel, so we'll have to 2189478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * filter in userland; in any case, we'll be doing 2190478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * filtering in userland, so we need to remove the 2191478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * total filter so we see packets. 2192478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 2193478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project save_errno = errno; 2194478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 2195478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 2196478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * XXX - if this fails, we're really screwed; 2197478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * we have the total filter on the socket, 2198478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * and it won't come off. What do we do then? 2199478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 2200478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project reset_kernel_filter(handle); 2201478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 2202478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project errno = save_errno; 2203478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project } 2204478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return ret; 2205478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project} 2206478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 2207478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectstatic int 2208478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Projectreset_kernel_filter(pcap_t *handle) 2209478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project{ 2210478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project /* 2211478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * setsockopt() barfs unless it get a dummy parameter. 2212478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * valgrind whines unless the value is initialized, 2213478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * as it has no idea that setsockopt() ignores its 2214478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project * parameter. 2215478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project */ 2216478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project int dummy = 0; 2217478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project 2218478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project return setsockopt(handle->fd, SOL_SOCKET, SO_DETACH_FILTER, 2219478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project &dummy, sizeof(dummy)); 2220478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project} 2221478ab6c8b5bc982589be32eae1e5736efe721b58The Android Open Source Project#endif 2222