1 /* 2 * Copyright 2008, 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 <stdio.h> 18 #include <stdlib.h> 19 #include <unistd.h> 20 #include <string.h> 21 #include <errno.h> 22 23 #include <sys/socket.h> 24 #include <sys/select.h> 25 #include <sys/types.h> 26 #include <netinet/in.h> 27 #include <arpa/inet.h> 28 29 #include <linux/if.h> 30 #include <linux/sockios.h> 31 #include <linux/route.h> 32 #include <linux/wireless.h> 33 34 #ifdef ANDROID 35 #define LOG_TAG "NetUtils" 36 #include <cutils/log.h> 37 #include <cutils/properties.h> 38 #else 39 #include <stdio.h> 40 #include <string.h> 41 #define LOGD printf 42 #define LOGW printf 43 #endif 44 45 static int ifc_ctl_sock = -1; 46 void printerr(char *fmt, ...); 47 48 static const char *ipaddr_to_string(uint32_t addr) 49 { 50 struct in_addr in_addr; 51 52 in_addr.s_addr = addr; 53 return inet_ntoa(in_addr); 54 } 55 56 int ifc_init(void) 57 { 58 if (ifc_ctl_sock == -1) { 59 ifc_ctl_sock = socket(AF_INET, SOCK_DGRAM, 0); 60 if (ifc_ctl_sock < 0) { 61 printerr("socket() failed: %s\n", strerror(errno)); 62 } 63 } 64 return ifc_ctl_sock < 0 ? -1 : 0; 65 } 66 67 void ifc_close(void) 68 { 69 if (ifc_ctl_sock != -1) { 70 (void)close(ifc_ctl_sock); 71 ifc_ctl_sock = -1; 72 } 73 } 74 75 static void ifc_init_ifr(const char *name, struct ifreq *ifr) 76 { 77 memset(ifr, 0, sizeof(struct ifreq)); 78 strncpy(ifr->ifr_name, name, IFNAMSIZ); 79 ifr->ifr_name[IFNAMSIZ - 1] = 0; 80 } 81 82 int ifc_get_hwaddr(const char *name, void *ptr) 83 { 84 int r; 85 struct ifreq ifr; 86 ifc_init_ifr(name, &ifr); 87 88 r = ioctl(ifc_ctl_sock, SIOCGIFHWADDR, &ifr); 89 if(r < 0) return -1; 90 91 memcpy(ptr, &ifr.ifr_hwaddr.sa_data, 6); 92 return 0; 93 } 94 95 int ifc_get_ifindex(const char *name, int *if_indexp) 96 { 97 int r; 98 struct ifreq ifr; 99 ifc_init_ifr(name, &ifr); 100 101 r = ioctl(ifc_ctl_sock, SIOCGIFINDEX, &ifr); 102 if(r < 0) return -1; 103 104 *if_indexp = ifr.ifr_ifindex; 105 return 0; 106 } 107 108 static int ifc_set_flags(const char *name, unsigned set, unsigned clr) 109 { 110 struct ifreq ifr; 111 ifc_init_ifr(name, &ifr); 112 113 if(ioctl(ifc_ctl_sock, SIOCGIFFLAGS, &ifr) < 0) return -1; 114 ifr.ifr_flags = (ifr.ifr_flags & (~clr)) | set; 115 return ioctl(ifc_ctl_sock, SIOCSIFFLAGS, &ifr); 116 } 117 118 int ifc_up(const char *name) 119 { 120 return ifc_set_flags(name, IFF_UP, 0); 121 } 122 123 int ifc_down(const char *name) 124 { 125 return ifc_set_flags(name, 0, IFF_UP); 126 } 127 128 static void init_sockaddr_in(struct sockaddr *sa, in_addr_t addr) 129 { 130 struct sockaddr_in *sin = (struct sockaddr_in *) sa; 131 sin->sin_family = AF_INET; 132 sin->sin_port = 0; 133 sin->sin_addr.s_addr = addr; 134 } 135 136 int ifc_set_addr(const char *name, in_addr_t addr) 137 { 138 struct ifreq ifr; 139 140 ifc_init_ifr(name, &ifr); 141 init_sockaddr_in(&ifr.ifr_addr, addr); 142 143 return ioctl(ifc_ctl_sock, SIOCSIFADDR, &ifr); 144 } 145 146 int ifc_set_mask(const char *name, in_addr_t mask) 147 { 148 struct ifreq ifr; 149 150 ifc_init_ifr(name, &ifr); 151 init_sockaddr_in(&ifr.ifr_addr, mask); 152 153 return ioctl(ifc_ctl_sock, SIOCSIFNETMASK, &ifr); 154 } 155 156 int ifc_get_info(const char *name, in_addr_t *addr, in_addr_t *mask, unsigned *flags) 157 { 158 struct ifreq ifr; 159 ifc_init_ifr(name, &ifr); 160 161 if (addr != NULL) { 162 if(ioctl(ifc_ctl_sock, SIOCGIFADDR, &ifr) < 0) { 163 *addr = 0; 164 } else { 165 *addr = ((struct sockaddr_in*) &ifr.ifr_addr)->sin_addr.s_addr; 166 } 167 } 168 169 if (mask != NULL) { 170 if(ioctl(ifc_ctl_sock, SIOCGIFNETMASK, &ifr) < 0) { 171 *mask = 0; 172 } else { 173 *mask = ((struct sockaddr_in*) &ifr.ifr_addr)->sin_addr.s_addr; 174 } 175 } 176 177 if (flags != NULL) { 178 if(ioctl(ifc_ctl_sock, SIOCGIFFLAGS, &ifr) < 0) { 179 *flags = 0; 180 } else { 181 *flags = ifr.ifr_flags; 182 } 183 } 184 185 return 0; 186 } 187 188 189 int ifc_create_default_route(const char *name, in_addr_t addr) 190 { 191 struct rtentry rt; 192 193 memset(&rt, 0, sizeof(rt)); 194 195 rt.rt_dst.sa_family = AF_INET; 196 rt.rt_flags = RTF_UP | RTF_GATEWAY; 197 rt.rt_dev = (void*) name; 198 init_sockaddr_in(&rt.rt_genmask, 0); 199 init_sockaddr_in(&rt.rt_gateway, addr); 200 201 return ioctl(ifc_ctl_sock, SIOCADDRT, &rt); 202 } 203 204 int ifc_add_host_route(const char *name, in_addr_t addr) 205 { 206 struct rtentry rt; 207 int result; 208 209 memset(&rt, 0, sizeof(rt)); 210 211 rt.rt_dst.sa_family = AF_INET; 212 rt.rt_flags = RTF_UP | RTF_HOST; 213 rt.rt_dev = (void*) name; 214 init_sockaddr_in(&rt.rt_dst, addr); 215 init_sockaddr_in(&rt.rt_genmask, 0); 216 init_sockaddr_in(&rt.rt_gateway, 0); 217 218 ifc_init(); 219 result = ioctl(ifc_ctl_sock, SIOCADDRT, &rt); 220 if (result < 0 && errno == EEXIST) { 221 result = 0; 222 } 223 ifc_close(); 224 return result; 225 } 226 227 int ifc_enable(const char *ifname) 228 { 229 int result; 230 231 ifc_init(); 232 result = ifc_up(ifname); 233 ifc_close(); 234 return result; 235 } 236 237 int ifc_disable(const char *ifname) 238 { 239 int result; 240 241 ifc_init(); 242 result = ifc_down(ifname); 243 ifc_set_addr(ifname, 0); 244 ifc_close(); 245 return result; 246 } 247 248 int ifc_reset_connections(const char *ifname) 249 { 250 #ifdef HAVE_ANDROID_OS 251 int result; 252 in_addr_t myaddr; 253 struct ifreq ifr; 254 255 ifc_init(); 256 ifc_get_info(ifname, &myaddr, NULL, NULL); 257 ifc_init_ifr(ifname, &ifr); 258 init_sockaddr_in(&ifr.ifr_addr, myaddr); 259 result = ioctl(ifc_ctl_sock, SIOCKILLADDR, &ifr); 260 ifc_close(); 261 262 return result; 263 #else 264 return 0; 265 #endif 266 } 267 268 /* 269 * Remove the routes associated with the named interface. 270 */ 271 int ifc_remove_host_routes(const char *name) 272 { 273 char ifname[64]; 274 in_addr_t dest, gway, mask; 275 int flags, refcnt, use, metric, mtu, win, irtt; 276 struct rtentry rt; 277 FILE *fp; 278 struct in_addr addr; 279 280 fp = fopen("/proc/net/route", "r"); 281 if (fp == NULL) 282 return -1; 283 /* Skip the header line */ 284 if (fscanf(fp, "%*[^\n]\n") < 0) { 285 fclose(fp); 286 return -1; 287 } 288 ifc_init(); 289 for (;;) { 290 int nread = fscanf(fp, "%63s%X%X%X%d%d%d%X%d%d%d\n", 291 ifname, &dest, &gway, &flags, &refcnt, &use, &metric, &mask, 292 &mtu, &win, &irtt); 293 if (nread != 11) { 294 break; 295 } 296 if ((flags & (RTF_UP|RTF_HOST)) != (RTF_UP|RTF_HOST) 297 || strcmp(ifname, name) != 0) { 298 continue; 299 } 300 memset(&rt, 0, sizeof(rt)); 301 rt.rt_dev = (void *)name; 302 init_sockaddr_in(&rt.rt_dst, dest); 303 init_sockaddr_in(&rt.rt_gateway, gway); 304 init_sockaddr_in(&rt.rt_genmask, mask); 305 addr.s_addr = dest; 306 if (ioctl(ifc_ctl_sock, SIOCDELRT, &rt) < 0) { 307 LOGD("failed to remove route for %s to %s: %s", 308 ifname, inet_ntoa(addr), strerror(errno)); 309 } 310 } 311 fclose(fp); 312 ifc_close(); 313 return 0; 314 } 315 316 /* 317 * Return the address of the default gateway 318 * 319 * TODO: factor out common code from this and remove_host_routes() 320 * so that we only scan /proc/net/route in one place. 321 */ 322 int ifc_get_default_route(const char *ifname) 323 { 324 char name[64]; 325 in_addr_t dest, gway, mask; 326 int flags, refcnt, use, metric, mtu, win, irtt; 327 int result; 328 FILE *fp; 329 330 fp = fopen("/proc/net/route", "r"); 331 if (fp == NULL) 332 return 0; 333 /* Skip the header line */ 334 if (fscanf(fp, "%*[^\n]\n") < 0) { 335 fclose(fp); 336 return 0; 337 } 338 ifc_init(); 339 result = 0; 340 for (;;) { 341 int nread = fscanf(fp, "%63s%X%X%X%d%d%d%X%d%d%d\n", 342 name, &dest, &gway, &flags, &refcnt, &use, &metric, &mask, 343 &mtu, &win, &irtt); 344 if (nread != 11) { 345 break; 346 } 347 if ((flags & (RTF_UP|RTF_GATEWAY)) == (RTF_UP|RTF_GATEWAY) 348 && dest == 0 349 && strcmp(ifname, name) == 0) { 350 result = gway; 351 break; 352 } 353 } 354 fclose(fp); 355 ifc_close(); 356 return result; 357 } 358 359 /* 360 * Sets the specified gateway as the default route for the named interface. 361 */ 362 int ifc_set_default_route(const char *ifname, in_addr_t gateway) 363 { 364 struct in_addr addr; 365 int result; 366 367 ifc_init(); 368 addr.s_addr = gateway; 369 if ((result = ifc_create_default_route(ifname, gateway)) < 0) { 370 LOGD("failed to add %s as default route for %s: %s", 371 inet_ntoa(addr), ifname, strerror(errno)); 372 } 373 ifc_close(); 374 return result; 375 } 376 377 /* 378 * Removes the default route for the named interface. 379 */ 380 int ifc_remove_default_route(const char *ifname) 381 { 382 struct rtentry rt; 383 int result; 384 385 ifc_init(); 386 memset(&rt, 0, sizeof(rt)); 387 rt.rt_dev = (void *)ifname; 388 rt.rt_flags = RTF_UP|RTF_GATEWAY; 389 init_sockaddr_in(&rt.rt_dst, 0); 390 if ((result = ioctl(ifc_ctl_sock, SIOCDELRT, &rt)) < 0) { 391 LOGD("failed to remove default route for %s: %s", ifname, strerror(errno)); 392 } 393 ifc_close(); 394 return result; 395 } 396 397 int 398 ifc_configure(const char *ifname, 399 in_addr_t address, 400 in_addr_t netmask, 401 in_addr_t gateway, 402 in_addr_t dns1, 403 in_addr_t dns2) { 404 405 char dns_prop_name[PROPERTY_KEY_MAX]; 406 407 ifc_init(); 408 409 if (ifc_up(ifname)) { 410 printerr("failed to turn on interface %s: %s\n", ifname, strerror(errno)); 411 ifc_close(); 412 return -1; 413 } 414 if (ifc_set_addr(ifname, address)) { 415 printerr("failed to set ipaddr %s: %s\n", ipaddr_to_string(address), strerror(errno)); 416 ifc_close(); 417 return -1; 418 } 419 if (ifc_set_mask(ifname, netmask)) { 420 printerr("failed to set netmask %s: %s\n", ipaddr_to_string(netmask), strerror(errno)); 421 ifc_close(); 422 return -1; 423 } 424 if (ifc_create_default_route(ifname, gateway)) { 425 printerr("failed to set default route %s: %s\n", ipaddr_to_string(gateway), strerror(errno)); 426 ifc_close(); 427 return -1; 428 } 429 430 ifc_close(); 431 432 snprintf(dns_prop_name, sizeof(dns_prop_name), "dhcp.%s.dns1", ifname); 433 property_set(dns_prop_name, dns1 ? ipaddr_to_string(dns1) : ""); 434 snprintf(dns_prop_name, sizeof(dns_prop_name), "dhcp.%s.dns2", ifname); 435 property_set(dns_prop_name, dns2 ? ipaddr_to_string(dns2) : ""); 436 437 return 0; 438 } 439
