153f17a9db278d33517d9888dd77848f554522a38JP Abgrall/* 253f17a9db278d33517d9888dd77848f554522a38JP Abgrall * This file implements decoding of ZeroMQ network protocol(s). 353f17a9db278d33517d9888dd77848f554522a38JP Abgrall * 453f17a9db278d33517d9888dd77848f554522a38JP Abgrall * 553f17a9db278d33517d9888dd77848f554522a38JP Abgrall * Copyright (c) 2013 The TCPDUMP project 653f17a9db278d33517d9888dd77848f554522a38JP Abgrall * All rights reserved. 753f17a9db278d33517d9888dd77848f554522a38JP Abgrall * 853f17a9db278d33517d9888dd77848f554522a38JP Abgrall * Redistribution and use in source and binary forms, with or without 953f17a9db278d33517d9888dd77848f554522a38JP Abgrall * modification, are permitted provided that the following conditions 1053f17a9db278d33517d9888dd77848f554522a38JP Abgrall * are met: 1153f17a9db278d33517d9888dd77848f554522a38JP Abgrall * 1. Redistributions of source code must retain the above copyright 1253f17a9db278d33517d9888dd77848f554522a38JP Abgrall * notice, this list of conditions and the following disclaimer. 1353f17a9db278d33517d9888dd77848f554522a38JP Abgrall * 2. Redistributions in binary form must reproduce the above copyright 1453f17a9db278d33517d9888dd77848f554522a38JP Abgrall * notice, this list of conditions and the following disclaimer in the 1553f17a9db278d33517d9888dd77848f554522a38JP Abgrall * documentation and/or other materials provided with the distribution. 1653f17a9db278d33517d9888dd77848f554522a38JP Abgrall * 1753f17a9db278d33517d9888dd77848f554522a38JP Abgrall * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 1853f17a9db278d33517d9888dd77848f554522a38JP Abgrall * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 1953f17a9db278d33517d9888dd77848f554522a38JP Abgrall * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 2053f17a9db278d33517d9888dd77848f554522a38JP Abgrall * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 2153f17a9db278d33517d9888dd77848f554522a38JP Abgrall * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 2253f17a9db278d33517d9888dd77848f554522a38JP Abgrall * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 2353f17a9db278d33517d9888dd77848f554522a38JP Abgrall * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 2453f17a9db278d33517d9888dd77848f554522a38JP Abgrall * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 2553f17a9db278d33517d9888dd77848f554522a38JP Abgrall * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2653f17a9db278d33517d9888dd77848f554522a38JP Abgrall * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 2753f17a9db278d33517d9888dd77848f554522a38JP Abgrall * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 2853f17a9db278d33517d9888dd77848f554522a38JP Abgrall * POSSIBILITY OF SUCH DAMAGE. 2953f17a9db278d33517d9888dd77848f554522a38JP Abgrall */ 3053f17a9db278d33517d9888dd77848f554522a38JP Abgrall 3153f17a9db278d33517d9888dd77848f554522a38JP Abgrall#ifdef HAVE_CONFIG_H 3253f17a9db278d33517d9888dd77848f554522a38JP Abgrall#include "config.h" 3353f17a9db278d33517d9888dd77848f554522a38JP Abgrall#endif 3453f17a9db278d33517d9888dd77848f554522a38JP Abgrall 3553f17a9db278d33517d9888dd77848f554522a38JP Abgrall#include <tcpdump-stdinc.h> 3653f17a9db278d33517d9888dd77848f554522a38JP Abgrall 3753f17a9db278d33517d9888dd77848f554522a38JP Abgrall#include <stdio.h> 3853f17a9db278d33517d9888dd77848f554522a38JP Abgrall 3953f17a9db278d33517d9888dd77848f554522a38JP Abgrall#include "interface.h" 4053f17a9db278d33517d9888dd77848f554522a38JP Abgrall#include "extract.h" 4153f17a9db278d33517d9888dd77848f554522a38JP Abgrall 4253f17a9db278d33517d9888dd77848f554522a38JP Abgrall/* Maximum number of ZMTP/1.0 frame body bytes (without the flags) to dump in 4353f17a9db278d33517d9888dd77848f554522a38JP Abgrall * hex and ASCII under a single "-v" flag. 4453f17a9db278d33517d9888dd77848f554522a38JP Abgrall */ 4553f17a9db278d33517d9888dd77848f554522a38JP Abgrall#define VBYTES 128 4653f17a9db278d33517d9888dd77848f554522a38JP Abgrall 4753f17a9db278d33517d9888dd77848f554522a38JP Abgrall/* 4853f17a9db278d33517d9888dd77848f554522a38JP Abgrall * Below is an excerpt from the "13/ZMTP" specification: 4953f17a9db278d33517d9888dd77848f554522a38JP Abgrall * 5053f17a9db278d33517d9888dd77848f554522a38JP Abgrall * A ZMTP message consists of 1 or more frames. 5153f17a9db278d33517d9888dd77848f554522a38JP Abgrall * 5253f17a9db278d33517d9888dd77848f554522a38JP Abgrall * A ZMTP frame consists of a length, followed by a flags field and a frame 5353f17a9db278d33517d9888dd77848f554522a38JP Abgrall * body of (length - 1) octets. Note: the length includes the flags field, so 5453f17a9db278d33517d9888dd77848f554522a38JP Abgrall * an empty frame has a length of 1. 5553f17a9db278d33517d9888dd77848f554522a38JP Abgrall * 5653f17a9db278d33517d9888dd77848f554522a38JP Abgrall * For frames with a length of 1 to 254 octets, the length SHOULD BE encoded 5753f17a9db278d33517d9888dd77848f554522a38JP Abgrall * as a single octet. The minimum valid length of a frame is 1 octet, thus a 5853f17a9db278d33517d9888dd77848f554522a38JP Abgrall * length of 0 is invalid and such frames SHOULD be discarded silently. 5953f17a9db278d33517d9888dd77848f554522a38JP Abgrall * 6053f17a9db278d33517d9888dd77848f554522a38JP Abgrall * For frames with lengths of 255 and greater, the length SHALL BE encoded as 6153f17a9db278d33517d9888dd77848f554522a38JP Abgrall * a single octet with the value 255, followed by the length encoded as a 6253f17a9db278d33517d9888dd77848f554522a38JP Abgrall * 64-bit unsigned integer in network byte order. For frames with lengths of 6353f17a9db278d33517d9888dd77848f554522a38JP Abgrall * 1 to 254 octets this encoding MAY be also used. 6453f17a9db278d33517d9888dd77848f554522a38JP Abgrall * 6553f17a9db278d33517d9888dd77848f554522a38JP Abgrall * The flags field consists of a single octet containing various control 6653f17a9db278d33517d9888dd77848f554522a38JP Abgrall * flags. Bit 0 is the least significant bit. 6753f17a9db278d33517d9888dd77848f554522a38JP Abgrall * 6853f17a9db278d33517d9888dd77848f554522a38JP Abgrall * - Bit 0 (MORE): More frames to follow. A value of 0 indicates that there 6953f17a9db278d33517d9888dd77848f554522a38JP Abgrall * are no more frames to follow. A value of 1 indicates that more frames 7053f17a9db278d33517d9888dd77848f554522a38JP Abgrall * will follow. On messages consisting of a single frame the MORE flag MUST 7153f17a9db278d33517d9888dd77848f554522a38JP Abgrall * be 0. 7253f17a9db278d33517d9888dd77848f554522a38JP Abgrall * 7353f17a9db278d33517d9888dd77848f554522a38JP Abgrall * - Bits 1-7: Reserved. Bits 1-7 are reserved for future use and SHOULD be 7453f17a9db278d33517d9888dd77848f554522a38JP Abgrall * zero. 7553f17a9db278d33517d9888dd77848f554522a38JP Abgrall */ 7653f17a9db278d33517d9888dd77848f554522a38JP Abgrall 7753f17a9db278d33517d9888dd77848f554522a38JP Abgrallstatic const u_char * 7853f17a9db278d33517d9888dd77848f554522a38JP Abgrallzmtp1_print_frame(const u_char *cp, const u_char *ep) { 7953f17a9db278d33517d9888dd77848f554522a38JP Abgrall u_int64_t body_len_declared, body_len_captured, header_len; 8053f17a9db278d33517d9888dd77848f554522a38JP Abgrall u_int8_t flags; 8153f17a9db278d33517d9888dd77848f554522a38JP Abgrall 8253f17a9db278d33517d9888dd77848f554522a38JP Abgrall printf("\n\t"); 8353f17a9db278d33517d9888dd77848f554522a38JP Abgrall TCHECK2(*cp, 1); /* length/0xFF */ 8453f17a9db278d33517d9888dd77848f554522a38JP Abgrall 8553f17a9db278d33517d9888dd77848f554522a38JP Abgrall if (cp[0] != 0xFF) { 8653f17a9db278d33517d9888dd77848f554522a38JP Abgrall header_len = 1; /* length */ 8753f17a9db278d33517d9888dd77848f554522a38JP Abgrall body_len_declared = cp[0]; 8853f17a9db278d33517d9888dd77848f554522a38JP Abgrall if (body_len_declared == 0) 8953f17a9db278d33517d9888dd77848f554522a38JP Abgrall return cp + header_len; /* skip to next frame */ 9053f17a9db278d33517d9888dd77848f554522a38JP Abgrall printf(" frame flags+body (8-bit) length %u", cp[0]); 9153f17a9db278d33517d9888dd77848f554522a38JP Abgrall TCHECK2(*cp, header_len + 1); /* length, flags */ 9253f17a9db278d33517d9888dd77848f554522a38JP Abgrall flags = cp[1]; 9353f17a9db278d33517d9888dd77848f554522a38JP Abgrall } else { 9453f17a9db278d33517d9888dd77848f554522a38JP Abgrall header_len = 1 + 8; /* 0xFF, length */ 9553f17a9db278d33517d9888dd77848f554522a38JP Abgrall printf(" frame flags+body (64-bit) length"); 9653f17a9db278d33517d9888dd77848f554522a38JP Abgrall TCHECK2(*cp, header_len); /* 0xFF, length */ 9753f17a9db278d33517d9888dd77848f554522a38JP Abgrall body_len_declared = EXTRACT_64BITS(cp + 1); 9853f17a9db278d33517d9888dd77848f554522a38JP Abgrall if (body_len_declared == 0) 9953f17a9db278d33517d9888dd77848f554522a38JP Abgrall return cp + header_len; /* skip to next frame */ 10053f17a9db278d33517d9888dd77848f554522a38JP Abgrall printf(" %" PRIu64, body_len_declared); 10153f17a9db278d33517d9888dd77848f554522a38JP Abgrall TCHECK2(*cp, header_len + 1); /* 0xFF, length, flags */ 10253f17a9db278d33517d9888dd77848f554522a38JP Abgrall flags = cp[9]; 10353f17a9db278d33517d9888dd77848f554522a38JP Abgrall } 10453f17a9db278d33517d9888dd77848f554522a38JP Abgrall 10553f17a9db278d33517d9888dd77848f554522a38JP Abgrall body_len_captured = ep - cp - header_len; 10653f17a9db278d33517d9888dd77848f554522a38JP Abgrall if (body_len_declared > body_len_captured) 10753f17a9db278d33517d9888dd77848f554522a38JP Abgrall printf(" (%" PRIu64 " captured)", body_len_captured); 10853f17a9db278d33517d9888dd77848f554522a38JP Abgrall printf(", flags 0x%02x", flags); 10953f17a9db278d33517d9888dd77848f554522a38JP Abgrall 11053f17a9db278d33517d9888dd77848f554522a38JP Abgrall if (vflag) { 11153f17a9db278d33517d9888dd77848f554522a38JP Abgrall u_int64_t body_len_printed = MIN(body_len_captured, body_len_declared); 11253f17a9db278d33517d9888dd77848f554522a38JP Abgrall 11353f17a9db278d33517d9888dd77848f554522a38JP Abgrall printf(" (%s|%s|%s|%s|%s|%s|%s|%s)", 11453f17a9db278d33517d9888dd77848f554522a38JP Abgrall flags & 0x80 ? "MBZ" : "-", 11553f17a9db278d33517d9888dd77848f554522a38JP Abgrall flags & 0x40 ? "MBZ" : "-", 11653f17a9db278d33517d9888dd77848f554522a38JP Abgrall flags & 0x20 ? "MBZ" : "-", 11753f17a9db278d33517d9888dd77848f554522a38JP Abgrall flags & 0x10 ? "MBZ" : "-", 11853f17a9db278d33517d9888dd77848f554522a38JP Abgrall flags & 0x08 ? "MBZ" : "-", 11953f17a9db278d33517d9888dd77848f554522a38JP Abgrall flags & 0x04 ? "MBZ" : "-", 12053f17a9db278d33517d9888dd77848f554522a38JP Abgrall flags & 0x02 ? "MBZ" : "-", 12153f17a9db278d33517d9888dd77848f554522a38JP Abgrall flags & 0x01 ? "MORE" : "-"); 12253f17a9db278d33517d9888dd77848f554522a38JP Abgrall 12353f17a9db278d33517d9888dd77848f554522a38JP Abgrall if (vflag == 1) 12453f17a9db278d33517d9888dd77848f554522a38JP Abgrall body_len_printed = MIN(VBYTES + 1, body_len_printed); 12553f17a9db278d33517d9888dd77848f554522a38JP Abgrall if (body_len_printed > 1) { 12653f17a9db278d33517d9888dd77848f554522a38JP Abgrall printf(", first %" PRIu64 " byte(s) of body:", body_len_printed - 1); 12753f17a9db278d33517d9888dd77848f554522a38JP Abgrall hex_and_ascii_print("\n\t ", cp + header_len + 1, body_len_printed - 1); 12853f17a9db278d33517d9888dd77848f554522a38JP Abgrall printf("\n"); 12953f17a9db278d33517d9888dd77848f554522a38JP Abgrall } 13053f17a9db278d33517d9888dd77848f554522a38JP Abgrall } 13153f17a9db278d33517d9888dd77848f554522a38JP Abgrall 13253f17a9db278d33517d9888dd77848f554522a38JP Abgrall TCHECK2(*cp, header_len + body_len_declared); /* Next frame within the buffer ? */ 13353f17a9db278d33517d9888dd77848f554522a38JP Abgrall return cp + header_len + body_len_declared; 13453f17a9db278d33517d9888dd77848f554522a38JP Abgrall 13553f17a9db278d33517d9888dd77848f554522a38JP Abgralltrunc: 13653f17a9db278d33517d9888dd77848f554522a38JP Abgrall printf(" [|zmtp1]"); 13753f17a9db278d33517d9888dd77848f554522a38JP Abgrall return ep; 13853f17a9db278d33517d9888dd77848f554522a38JP Abgrall} 13953f17a9db278d33517d9888dd77848f554522a38JP Abgrall 14053f17a9db278d33517d9888dd77848f554522a38JP Abgrallvoid 14153f17a9db278d33517d9888dd77848f554522a38JP Abgrallzmtp1_print(const u_char *cp, u_int len) { 14253f17a9db278d33517d9888dd77848f554522a38JP Abgrall const u_char *ep = MIN(snapend, cp + len); 14353f17a9db278d33517d9888dd77848f554522a38JP Abgrall 14453f17a9db278d33517d9888dd77848f554522a38JP Abgrall printf(": ZMTP/1.0"); 14553f17a9db278d33517d9888dd77848f554522a38JP Abgrall while (cp < ep) 14653f17a9db278d33517d9888dd77848f554522a38JP Abgrall cp = zmtp1_print_frame(cp, ep); 14753f17a9db278d33517d9888dd77848f554522a38JP Abgrall} 14853f17a9db278d33517d9888dd77848f554522a38JP Abgrall 14953f17a9db278d33517d9888dd77848f554522a38JP Abgrall/* The functions below decode a ZeroMQ datagram, supposedly stored in the "Data" 15053f17a9db278d33517d9888dd77848f554522a38JP Abgrall * field of an ODATA/RDATA [E]PGM packet. An excerpt from zmq_pgm(7) man page 15153f17a9db278d33517d9888dd77848f554522a38JP Abgrall * follows. 15253f17a9db278d33517d9888dd77848f554522a38JP Abgrall * 15353f17a9db278d33517d9888dd77848f554522a38JP Abgrall * In order for late joining consumers to be able to identify message 15453f17a9db278d33517d9888dd77848f554522a38JP Abgrall * boundaries, each PGM datagram payload starts with a 16-bit unsigned integer 15553f17a9db278d33517d9888dd77848f554522a38JP Abgrall * in network byte order specifying either the offset of the first message frame 15653f17a9db278d33517d9888dd77848f554522a38JP Abgrall * in the datagram or containing the value 0xFFFF if the datagram contains 15753f17a9db278d33517d9888dd77848f554522a38JP Abgrall * solely an intermediate part of a larger message. 15853f17a9db278d33517d9888dd77848f554522a38JP Abgrall * 15953f17a9db278d33517d9888dd77848f554522a38JP Abgrall * Note that offset specifies where the first message begins rather than the 16053f17a9db278d33517d9888dd77848f554522a38JP Abgrall * first message part. Thus, if there are trailing message parts at the 16153f17a9db278d33517d9888dd77848f554522a38JP Abgrall * beginning of the packet the offset ignores them and points to first initial 16253f17a9db278d33517d9888dd77848f554522a38JP Abgrall * message part in the packet. 16353f17a9db278d33517d9888dd77848f554522a38JP Abgrall */ 16453f17a9db278d33517d9888dd77848f554522a38JP Abgrall 16553f17a9db278d33517d9888dd77848f554522a38JP Abgrallstatic const u_char * 16653f17a9db278d33517d9888dd77848f554522a38JP Abgrallzmtp1_print_intermediate_part(const u_char *cp, const u_int len) { 16753f17a9db278d33517d9888dd77848f554522a38JP Abgrall u_int frame_offset; 16853f17a9db278d33517d9888dd77848f554522a38JP Abgrall u_int64_t remaining_len; 16953f17a9db278d33517d9888dd77848f554522a38JP Abgrall 17053f17a9db278d33517d9888dd77848f554522a38JP Abgrall TCHECK2(*cp, 2); 17153f17a9db278d33517d9888dd77848f554522a38JP Abgrall frame_offset = EXTRACT_16BITS(cp); 17253f17a9db278d33517d9888dd77848f554522a38JP Abgrall printf("\n\t frame offset 0x%04x", frame_offset); 17353f17a9db278d33517d9888dd77848f554522a38JP Abgrall cp += 2; 17453f17a9db278d33517d9888dd77848f554522a38JP Abgrall remaining_len = snapend - cp; /* without the frame length */ 17553f17a9db278d33517d9888dd77848f554522a38JP Abgrall 17653f17a9db278d33517d9888dd77848f554522a38JP Abgrall if (frame_offset == 0xFFFF) 17753f17a9db278d33517d9888dd77848f554522a38JP Abgrall frame_offset = len - 2; /* always within the declared length */ 17853f17a9db278d33517d9888dd77848f554522a38JP Abgrall else if (2 + frame_offset > len) { 17953f17a9db278d33517d9888dd77848f554522a38JP Abgrall printf(" (exceeds datagram declared length)"); 18053f17a9db278d33517d9888dd77848f554522a38JP Abgrall goto trunc; 18153f17a9db278d33517d9888dd77848f554522a38JP Abgrall } 18253f17a9db278d33517d9888dd77848f554522a38JP Abgrall 18353f17a9db278d33517d9888dd77848f554522a38JP Abgrall /* offset within declared length of the datagram */ 18453f17a9db278d33517d9888dd77848f554522a38JP Abgrall if (frame_offset) { 18553f17a9db278d33517d9888dd77848f554522a38JP Abgrall printf("\n\t frame intermediate part, %u bytes", frame_offset); 18653f17a9db278d33517d9888dd77848f554522a38JP Abgrall if (frame_offset > remaining_len) 18753f17a9db278d33517d9888dd77848f554522a38JP Abgrall printf(" (%"PRIu64" captured)", remaining_len); 18853f17a9db278d33517d9888dd77848f554522a38JP Abgrall if (vflag) { 18953f17a9db278d33517d9888dd77848f554522a38JP Abgrall u_int64_t len_printed = MIN(frame_offset, remaining_len); 19053f17a9db278d33517d9888dd77848f554522a38JP Abgrall 19153f17a9db278d33517d9888dd77848f554522a38JP Abgrall if (vflag == 1) 19253f17a9db278d33517d9888dd77848f554522a38JP Abgrall len_printed = MIN(VBYTES, len_printed); 19353f17a9db278d33517d9888dd77848f554522a38JP Abgrall if (len_printed > 1) { 19453f17a9db278d33517d9888dd77848f554522a38JP Abgrall printf(", first %"PRIu64" byte(s):", len_printed); 19553f17a9db278d33517d9888dd77848f554522a38JP Abgrall hex_and_ascii_print("\n\t ", cp, len_printed); 19653f17a9db278d33517d9888dd77848f554522a38JP Abgrall printf("\n"); 19753f17a9db278d33517d9888dd77848f554522a38JP Abgrall } 19853f17a9db278d33517d9888dd77848f554522a38JP Abgrall } 19953f17a9db278d33517d9888dd77848f554522a38JP Abgrall } 20053f17a9db278d33517d9888dd77848f554522a38JP Abgrall return cp + frame_offset; 20153f17a9db278d33517d9888dd77848f554522a38JP Abgrall 20253f17a9db278d33517d9888dd77848f554522a38JP Abgralltrunc: 20353f17a9db278d33517d9888dd77848f554522a38JP Abgrall printf(" [|zmtp1]"); 20453f17a9db278d33517d9888dd77848f554522a38JP Abgrall return cp + len; 20553f17a9db278d33517d9888dd77848f554522a38JP Abgrall} 20653f17a9db278d33517d9888dd77848f554522a38JP Abgrall 20753f17a9db278d33517d9888dd77848f554522a38JP Abgrallvoid 20853f17a9db278d33517d9888dd77848f554522a38JP Abgrallzmtp1_print_datagram(const u_char *cp, const u_int len) { 20953f17a9db278d33517d9888dd77848f554522a38JP Abgrall const u_char *ep = MIN(snapend, cp + len); 21053f17a9db278d33517d9888dd77848f554522a38JP Abgrall 21153f17a9db278d33517d9888dd77848f554522a38JP Abgrall cp = zmtp1_print_intermediate_part(cp, len); 21253f17a9db278d33517d9888dd77848f554522a38JP Abgrall while (cp < ep) 21353f17a9db278d33517d9888dd77848f554522a38JP Abgrall cp = zmtp1_print_frame(cp, ep); 21453f17a9db278d33517d9888dd77848f554522a38JP Abgrall} 215