1 /* $FreeBSD$ */ 2 3 /* 4 * Copyright (c) 1995, 1999 5 * Berkeley Software Design, Inc. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 13 * THIS SOFTWARE IS PROVIDED BY Berkeley Software Design, Inc. ``AS IS'' AND 14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16 * ARE DISCLAIMED. IN NO EVENT SHALL Berkeley Software Design, Inc. BE LIABLE 17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23 * SUCH DAMAGE. 24 * 25 * BSDI getifaddrs.c,v 2.12 2000/02/23 14:51:59 dab Exp 26 */ 27 /* 28 * NOTE: SIOCGIFCONF case is not LP64 friendly. it also does not perform 29 * try-and-error for region size. 30 */ 31 #include <sys/types.h> 32 #include <sys/ioctl.h> 33 #include <sys/socket.h> 34 #include <net/if.h> 35 #ifdef NET_RT_IFLIST 36 #include <sys/param.h> 37 #include <net/route.h> 38 #include <sys/sysctl.h> 39 #include <net/if_dl.h> 40 #endif 41 42 #include <errno.h> 43 #include <ifaddrs.h> 44 #include <stdlib.h> 45 #include <string.h> 46 47 #if !defined(AF_LINK) 48 #define SA_LEN(sa) sizeof(struct sockaddr) 49 #endif 50 51 #if !defined(SA_LEN) 52 #define SA_LEN(sa) (sa)->sa_len 53 #endif 54 55 #define SALIGN (sizeof(long) - 1) 56 #define SA_RLEN(sa) ((sa)->sa_len ? (((sa)->sa_len + SALIGN) & ~SALIGN) : (SALIGN + 1)) 57 58 #ifndef ALIGNBYTES 59 /* 60 * On systems with a routing socket, ALIGNBYTES should match the value 61 * that the kernel uses when building the messages. 62 */ 63 #define ALIGNBYTES XXX 64 #endif 65 #ifndef ALIGN 66 #define ALIGN(p) (((u_long)(p) + ALIGNBYTES) &~ ALIGNBYTES) 67 #endif 68 69 #if _BSDI_VERSION >= 199701 70 #define HAVE_IFM_DATA 71 #endif 72 73 #if _BSDI_VERSION >= 199802 74 /* ifam_data is very specific to recent versions of bsdi */ 75 #define HAVE_IFAM_DATA 76 #endif 77 78 #if defined(__NetBSD__) || defined(__OpenBSD__) || defined(__FreeBSD__) 79 #define HAVE_IFM_DATA 80 #endif 81 82 int 83 getifaddrs(struct ifaddrs **pif) 84 { 85 int icnt = 1; 86 int dcnt = 0; 87 int ncnt = 0; 88 #ifdef NET_RT_IFLIST 89 int mib[6]; 90 size_t needed; 91 char *buf; 92 char *next; 93 struct ifaddrs *cif = 0; 94 char *p, *p0; 95 struct rt_msghdr *rtm; 96 struct if_msghdr *ifm; 97 struct ifa_msghdr *ifam; 98 struct sockaddr_dl *dl; 99 struct sockaddr *sa; 100 struct ifaddrs *ifa, *ift; 101 u_short index = 0; 102 #else /* NET_RT_IFLIST */ 103 char buf[1024]; 104 int m, sock; 105 struct ifconf ifc; 106 struct ifreq *ifr; 107 struct ifreq *lifr; 108 #endif /* NET_RT_IFLIST */ 109 int i; 110 size_t len, alen; 111 char *data; 112 char *names; 113 114 #ifdef NET_RT_IFLIST 115 mib[0] = CTL_NET; 116 mib[1] = PF_ROUTE; 117 mib[2] = 0; /* protocol */ 118 mib[3] = 0; /* wildcard address family */ 119 mib[4] = NET_RT_IFLIST; 120 mib[5] = 0; /* no flags */ 121 if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0) 122 return (-1); 123 if ((buf = malloc(needed)) == NULL) 124 return (-1); 125 if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0) { 126 free(buf); 127 return (-1); 128 } 129 130 for (next = buf; next < buf + needed; next += rtm->rtm_msglen) { 131 rtm = (struct rt_msghdr *)next; 132 if (rtm->rtm_version != RTM_VERSION) 133 continue; 134 switch (rtm->rtm_type) { 135 case RTM_IFINFO: 136 ifm = (struct if_msghdr *)rtm; 137 if (ifm->ifm_addrs & RTA_IFP) { 138 index = ifm->ifm_index; 139 ++icnt; 140 dl = (struct sockaddr_dl *)(ifm + 1); 141 dcnt += SA_RLEN((struct sockaddr *)dl) + 142 ALIGNBYTES; 143 #ifdef HAVE_IFM_DATA 144 dcnt += sizeof(ifm->ifm_data); 145 #endif /* HAVE_IFM_DATA */ 146 ncnt += dl->sdl_nlen + 1; 147 } else 148 index = 0; 149 break; 150 151 case RTM_NEWADDR: 152 ifam = (struct ifa_msghdr *)rtm; 153 if (index && ifam->ifam_index != index) 154 abort(); /* this cannot happen */ 155 156 #define RTA_MASKS (RTA_NETMASK | RTA_IFA | RTA_BRD) 157 if (index == 0 || (ifam->ifam_addrs & RTA_MASKS) == 0) 158 break; 159 p = (char *)(ifam + 1); 160 ++icnt; 161 #ifdef HAVE_IFAM_DATA 162 dcnt += sizeof(ifam->ifam_data) + ALIGNBYTES; 163 #endif /* HAVE_IFAM_DATA */ 164 /* Scan to look for length of address */ 165 alen = 0; 166 for (p0 = p, i = 0; i < RTAX_MAX; i++) { 167 if ((RTA_MASKS & ifam->ifam_addrs & (1 << i)) 168 == 0) 169 continue; 170 sa = (struct sockaddr *)p; 171 len = SA_RLEN(sa); 172 if (i == RTAX_IFA) { 173 alen = len; 174 break; 175 } 176 p += len; 177 } 178 for (p = p0, i = 0; i < RTAX_MAX; i++) { 179 if ((RTA_MASKS & ifam->ifam_addrs & (1 << i)) 180 == 0) 181 continue; 182 sa = (struct sockaddr *)p; 183 len = SA_RLEN(sa); 184 if (i == RTAX_NETMASK && SA_LEN(sa) == 0) 185 dcnt += alen; 186 else 187 dcnt += len; 188 p += len; 189 } 190 break; 191 } 192 } 193 #else /* NET_RT_IFLIST */ 194 ifc.ifc_buf = buf; 195 ifc.ifc_len = sizeof(buf); 196 197 if ((sock = socket(AF_INET, SOCK_STREAM, 0)) < 0) 198 return (-1); 199 i = ioctl(sock, SIOCGIFCONF, (char *)&ifc); 200 close(sock); 201 if (i < 0) 202 return (-1); 203 204 ifr = ifc.ifc_req; 205 lifr = (struct ifreq *)&ifc.ifc_buf[ifc.ifc_len]; 206 207 while (ifr < lifr) { 208 struct sockaddr *sa; 209 210 sa = &ifr->ifr_addr; 211 ++icnt; 212 dcnt += SA_RLEN(sa); 213 ncnt += sizeof(ifr->ifr_name) + 1; 214 215 ifr = (struct ifreq *)(((char *)sa) + SA_LEN(sa)); 216 } 217 #endif /* NET_RT_IFLIST */ 218 219 if (icnt + dcnt + ncnt == 1) { 220 *pif = NULL; 221 free(buf); 222 return (0); 223 } 224 data = malloc(sizeof(struct ifaddrs) * icnt + dcnt + ncnt); 225 if (data == NULL) { 226 free(buf); 227 return(-1); 228 } 229 230 ifa = (struct ifaddrs *)data; 231 data += sizeof(struct ifaddrs) * icnt; 232 names = data + dcnt; 233 234 memset(ifa, 0, sizeof(struct ifaddrs) * icnt); 235 ift = ifa; 236 237 #ifdef NET_RT_IFLIST 238 index = 0; 239 for (next = buf; next < buf + needed; next += rtm->rtm_msglen) { 240 rtm = (struct rt_msghdr *)next; 241 if (rtm->rtm_version != RTM_VERSION) 242 continue; 243 switch (rtm->rtm_type) { 244 case RTM_IFINFO: 245 ifm = (struct if_msghdr *)rtm; 246 if (ifm->ifm_addrs & RTA_IFP) { 247 index = ifm->ifm_index; 248 dl = (struct sockaddr_dl *)(ifm + 1); 249 250 cif = ift; 251 ift->ifa_name = names; 252 ift->ifa_flags = (int)ifm->ifm_flags; 253 memcpy(names, dl->sdl_data, dl->sdl_nlen); 254 names[dl->sdl_nlen] = 0; 255 names += dl->sdl_nlen + 1; 256 257 ift->ifa_addr = (struct sockaddr *)data; 258 memcpy(data, dl, SA_LEN((struct sockaddr *)dl)); 259 data += SA_RLEN((struct sockaddr *)dl); 260 261 #ifdef HAVE_IFM_DATA 262 /* ifm_data needs to be aligned */ 263 ift->ifa_data = data = (void *)ALIGN(data); 264 memcpy(data, &ifm->ifm_data, sizeof(ifm->ifm_data)); 265 data += sizeof(ifm->ifm_data); 266 #else /* HAVE_IFM_DATA */ 267 ift->ifa_data = NULL; 268 #endif /* HAVE_IFM_DATA */ 269 270 ift = (ift->ifa_next = ift + 1); 271 } else 272 index = 0; 273 break; 274 275 case RTM_NEWADDR: 276 ifam = (struct ifa_msghdr *)rtm; 277 if (index && ifam->ifam_index != index) 278 abort(); /* this cannot happen */ 279 280 if (index == 0 || (ifam->ifam_addrs & RTA_MASKS) == 0) 281 break; 282 ift->ifa_name = cif->ifa_name; 283 ift->ifa_flags = cif->ifa_flags; 284 ift->ifa_data = NULL; 285 p = (char *)(ifam + 1); 286 /* Scan to look for length of address */ 287 alen = 0; 288 for (p0 = p, i = 0; i < RTAX_MAX; i++) { 289 if ((RTA_MASKS & ifam->ifam_addrs & (1 << i)) 290 == 0) 291 continue; 292 sa = (struct sockaddr *)p; 293 len = SA_RLEN(sa); 294 if (i == RTAX_IFA) { 295 alen = len; 296 break; 297 } 298 p += len; 299 } 300 for (p = p0, i = 0; i < RTAX_MAX; i++) { 301 if ((RTA_MASKS & ifam->ifam_addrs & (1 << i)) 302 == 0) 303 continue; 304 sa = (struct sockaddr *)p; 305 len = SA_RLEN(sa); 306 switch (i) { 307 case RTAX_IFA: 308 ift->ifa_addr = (struct sockaddr *)data; 309 memcpy(data, p, len); 310 data += len; 311 break; 312 313 case RTAX_NETMASK: 314 ift->ifa_netmask = 315 (struct sockaddr *)data; 316 if (SA_LEN(sa) == 0) { 317 memset(data, 0, alen); 318 data += alen; 319 break; 320 } 321 memcpy(data, p, len); 322 data += len; 323 break; 324 325 case RTAX_BRD: 326 ift->ifa_broadaddr = 327 (struct sockaddr *)data; 328 memcpy(data, p, len); 329 data += len; 330 break; 331 } 332 p += len; 333 } 334 335 #ifdef HAVE_IFAM_DATA 336 /* ifam_data needs to be aligned */ 337 ift->ifa_data = data = (void *)ALIGN(data); 338 memcpy(data, &ifam->ifam_data, sizeof(ifam->ifam_data)); 339 data += sizeof(ifam->ifam_data); 340 #endif /* HAVE_IFAM_DATA */ 341 342 ift = (ift->ifa_next = ift + 1); 343 break; 344 } 345 } 346 347 free(buf); 348 #else /* NET_RT_IFLIST */ 349 ifr = ifc.ifc_req; 350 lifr = (struct ifreq *)&ifc.ifc_buf[ifc.ifc_len]; 351 352 while (ifr < lifr) { 353 struct sockaddr *sa; 354 355 ift->ifa_name = names; 356 names[sizeof(ifr->ifr_name)] = 0; 357 strncpy(names, ifr->ifr_name, sizeof(ifr->ifr_name)); 358 while (*names++) 359 ; 360 361 ift->ifa_addr = (struct sockaddr *)data; 362 sa = &ifr->ifr_addr; 363 memcpy(data, sa, SA_LEN(sa)); 364 data += SA_RLEN(sa); 365 366 ifr = (struct ifreq *)(((char *)sa) + SA_LEN(sa)); 367 ift = (ift->ifa_next = ift + 1); 368 } 369 #endif /* NET_RT_IFLIST */ 370 if (--ift >= ifa) { 371 ift->ifa_next = NULL; 372 *pif = ifa; 373 } else { 374 *pif = NULL; 375 free(ifa); 376 } 377 return (0); 378 } 379 380 void 381 freeifaddrs(struct ifaddrs *ifp) 382 { 383 free(ifp); 384 } 385