DnsProxyListener.cpp revision 1dbd6cf148ea3fab57ec0644c336e94c78a488be
1/* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17#include <arpa/inet.h> 18#include <dirent.h> 19#include <errno.h> 20#include <linux/if.h> 21#include <netdb.h> 22#include <netinet/in.h> 23#include <stdlib.h> 24#include <sys/socket.h> 25#include <sys/types.h> 26 27#define LOG_TAG "DnsProxyListener" 28#define DBG 0 29 30#include <cutils/log.h> 31#include <sysutils/SocketClient.h> 32 33#include "DnsProxyListener.h" 34 35DnsProxyListener::DnsProxyListener() : 36 FrameworkListener("dnsproxyd") { 37 registerCmd(new GetAddrInfoCmd()); 38 registerCmd(new GetHostByAddrCmd()); 39} 40 41DnsProxyListener::GetAddrInfoHandler::~GetAddrInfoHandler() { 42 free(mHost); 43 free(mService); 44 free(mHints); 45} 46 47void DnsProxyListener::GetAddrInfoHandler::start() { 48 pthread_create(&mThread, NULL, 49 DnsProxyListener::GetAddrInfoHandler::threadStart, this); 50} 51 52void* DnsProxyListener::GetAddrInfoHandler::threadStart(void* obj) { 53 GetAddrInfoHandler* handler = reinterpret_cast<GetAddrInfoHandler*>(obj); 54 handler->run(); 55 delete handler; 56 pthread_exit(NULL); 57 return NULL; 58} 59 60// Sends 4 bytes of big-endian length, followed by the data. 61// Returns true on success. 62static bool sendLenAndData(SocketClient *c, const int len, const void* data) { 63 uint32_t len_be = htonl(len); 64 return c->sendData(&len_be, 4) == 0 && 65 (len == 0 || c->sendData(data, len) == 0); 66} 67 68void DnsProxyListener::GetAddrInfoHandler::run() { 69 if (DBG) { 70 LOGD("GetAddrInfoHandler, now for %s / %s", mHost, mService); 71 } 72 73 struct addrinfo* result = NULL; 74 int rv = getaddrinfo(mHost, mService, mHints, &result); 75 bool success = (mClient->sendData(&rv, sizeof(rv)) == 0); 76 if (rv == 0) { 77 struct addrinfo* ai = result; 78 while (ai && success) { 79 success = sendLenAndData(mClient, sizeof(struct addrinfo), ai) 80 && sendLenAndData(mClient, ai->ai_addrlen, ai->ai_addr) 81 && sendLenAndData(mClient, 82 ai->ai_canonname ? strlen(ai->ai_canonname) + 1 : 0, 83 ai->ai_canonname); 84 ai = ai->ai_next; 85 } 86 success = success && sendLenAndData(mClient, 0, ""); 87 } 88 if (result) { 89 freeaddrinfo(result); 90 } 91 if (!success) { 92 LOGW("Error writing DNS result to client"); 93 } 94} 95 96DnsProxyListener::GetAddrInfoCmd::GetAddrInfoCmd() : 97 NetdCommand("getaddrinfo") { 98} 99 100int DnsProxyListener::GetAddrInfoCmd::runCommand(SocketClient *cli, 101 int argc, char **argv) { 102 if (argc != 7) { 103 LOGW("Invalid number of arguments to getaddrinfo"); 104 return 0; 105 } 106 107 char* name = argv[1]; 108 if (strcmp("^", name) == 0) { 109 name = NULL; 110 } else { 111 name = strdup(name); 112 } 113 114 char* service = argv[2]; 115 if (strcmp("^", service) == 0) { 116 service = NULL; 117 } else { 118 service = strdup(service); 119 } 120 121 struct addrinfo* hints = NULL; 122 int ai_flags = atoi(argv[3]); 123 int ai_family = atoi(argv[4]); 124 int ai_socktype = atoi(argv[5]); 125 int ai_protocol = atoi(argv[6]); 126 if (ai_flags != -1 || ai_family != -1 || 127 ai_socktype != -1 || ai_protocol != -1) { 128 hints = (struct addrinfo*) calloc(1, sizeof(struct addrinfo)); 129 hints->ai_flags = ai_flags; 130 hints->ai_family = ai_family; 131 hints->ai_socktype = ai_socktype; 132 hints->ai_protocol = ai_protocol; 133 } 134 135 if (DBG) { 136 LOGD("GetAddrInfoHandler for %s / %s", 137 name ? name : "[nullhost]", 138 service ? service : "[nullservice]"); 139 } 140 141 DnsProxyListener::GetAddrInfoHandler* handler = 142 new DnsProxyListener::GetAddrInfoHandler(cli, name, service, hints); 143 handler->start(); 144 145 146 return 0; 147} 148 149/******************************************************* 150 * GetHostByAddr * 151 *******************************************************/ 152DnsProxyListener::GetHostByAddrCmd::GetHostByAddrCmd() : 153 NetdCommand("gethostbyaddr") { 154} 155 156int DnsProxyListener::GetHostByAddrCmd::runCommand(SocketClient *cli, 157 int argc, char **argv) { 158 if (argc != 4) { 159 LOGW("Invalid number of arguments to gethostbyaddr"); 160 return 0; 161 } 162 163 char* addr = argv[1]; 164 addr = strdup(addr); 165 166 int addrLen = atoi(argv[2]); 167 int addrFamily = atoi(argv[3]); 168 169 DnsProxyListener::GetHostByAddrHandler* handler = 170 new DnsProxyListener::GetHostByAddrHandler(cli, addr, addrLen, addrFamily); 171 handler->start(); 172 173 return 0; 174} 175 176DnsProxyListener::GetHostByAddrHandler::~GetHostByAddrHandler() { 177 free(mAddress); 178} 179 180void DnsProxyListener::GetHostByAddrHandler::start() { 181 pthread_create(&mThread, NULL, 182 DnsProxyListener::GetHostByAddrHandler::threadStart, this); 183} 184 185void* DnsProxyListener::GetHostByAddrHandler::threadStart(void* obj) { 186 GetHostByAddrHandler* handler = reinterpret_cast<GetHostByAddrHandler*>(obj); 187 handler->run(); 188 delete handler; 189 pthread_exit(NULL); 190 return NULL; 191} 192 193void DnsProxyListener::GetHostByAddrHandler::run() { 194 if (DBG) { 195 LOGD("DnsProxyListener::GetHostByAddrHandler::run\n"); 196 if (mAddress) { 197 LOGD("mAdress %u.%u.%u.%u mAdressLen %d, mAddressFamily %d", 198 mAddress[0], mAddress[1], mAddress[2], mAddress[3], 199 mAddressLen, mAddressFamily); 200 } 201 else { 202 LOGD("mAddress = NULL"); 203 } 204 } 205 206 struct hostent* hp; 207 208 hp = gethostbyaddr(mAddress, mAddressLen, mAddressFamily); 209 210 if (DBG) { 211 LOGD("GetHostByAddrHandler::run gethostbyaddr errno: %s hp->h_name = %s, name_len = %d\n", 212 hp ? "success" : strerror(errno), 213 (hp && hp->h_name) ? hp->h_name: "null", 214 (hp && hp->h_name) ? strlen(hp->h_name)+ 1 : 0); 215 } 216 217 bool success = sendLenAndData(mClient, (hp && hp->h_name) ? strlen(hp->h_name)+ 1 : 0, 218 (hp && hp->h_name) ? hp->h_name : ""); 219 220 if (!success) { 221 LOGW("GetHostByAddrHandler: Error writing DNS result to client\n"); 222 } 223} 224