1 /* $NetBSD: getifaddrs.c,v 1.1 2000/02/23 06:57:46 itojun Exp $ */ 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 2.11 1999/03/15 20:57:20 jch Exp 26 */ 27 #include <sys/types.h> 28 #include <sys/ioctl.h> 29 #include <sys/socket.h> 30 #include <net/if.h> 31 #ifdef NET_RT_IFLIST 32 #include <sys/param.h> 33 #include <net/route.h> 34 #include <sys/sysctl.h> 35 #include <net/if_dl.h> 36 #endif 37 38 #include <errno.h> 39 #include <ifaddrs.h> 40 #include <stdlib.h> 41 #include <string.h> 42 43 #if !defined(AF_LINK) 44 #define SA_LEN(sa) sizeof(struct sockaddr) 45 #endif 46 47 #if !defined(SA_LEN) 48 #define SA_LEN(sa) (sa)->sa_len 49 #endif 50 51 #define SALIGN (sizeof(long) - 1) 52 #define SA_RLEN(sa) ((sa)->sa_len ? (((sa)->sa_len + SALIGN) & ~SALIGN) : (SALIGN + 1)) 53 54 #ifndef ALIGNBYTES 55 /* 56 * On systems with a routing socket, ALIGNBYTES should match the value 57 * that the kernel uses when building the messages. 58 */ 59 #define ALIGNBYTES XXX 60 #endif 61 #ifndef ALIGN 62 #define ALIGN(p) (((u_long)(p) + ALIGNBYTES) &~ ALIGNBYTES) 63 #endif 64 65 #if _BSDI_VERSION >= 199701 66 #define HAVE_IFM_DATA 67 #endif 68 69 #if _BSDI_VERSION >= 199802 70 #define HAVE_IFAM_DATA 71 #endif 72 73 int 74 getifaddrs(struct ifaddrs **pif) 75 { 76 int icnt = 1; 77 int dcnt = 0; 78 int ncnt = 0; 79 #ifdef NET_RT_IFLIST 80 int mib[6]; 81 size_t needed; 82 char *buf; 83 char *next; 84 struct ifaddrs *cif = 0; 85 char *p, *p0; 86 struct rt_msghdr *rtm; 87 struct if_msghdr *ifm; 88 struct ifa_msghdr *ifam; 89 struct sockaddr_dl *dl; 90 struct sockaddr *sa; 91 struct ifaddrs *ifa, *ift; 92 u_short index = 0; 93 #else /* NET_RT_IFLIST */ 94 char buf[1024]; 95 int m, sock; 96 struct ifconf ifc; 97 struct ifreq *ifr; 98 struct ifreq *lifr; 99 #endif /* NET_RT_IFLIST */ 100 int i; 101 size_t len, alen; 102 char *data; 103 char *names; 104 105 #ifdef NET_RT_IFLIST 106 mib[0] = CTL_NET; 107 mib[1] = PF_ROUTE; 108 mib[2] = 0; /* protocol */ 109 mib[3] = 0; /* wildcard address family */ 110 mib[4] = NET_RT_IFLIST; 111 mib[5] = 0; /* no flags */ 112 if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0) 113 return (-1); 114 if ((buf = malloc(needed)) == NULL) 115 return (-1); 116 if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0) { 117 free(buf); 118 return (-1); 119 } 120 121 for (next = buf; next < buf + needed; next += rtm->rtm_msglen) { 122 rtm = (struct rt_msghdr *)next; 123 if (rtm->rtm_version != RTM_VERSION) 124 continue; 125 switch (rtm->rtm_type) { 126 case RTM_IFINFO: 127 ifm = (struct if_msghdr *)rtm; 128 if (ifm->ifm_addrs & RTA_IFP) { 129 index = ifm->ifm_index; 130 ++icnt; 131 dl = (struct sockaddr_dl *)(ifm + 1); 132 dcnt += SA_RLEN((struct sockaddr *)dl) + 133 ALIGNBYTES; 134 #ifdef HAVE_IFM_DATA 135 dcnt += sizeof(ifm->ifm_data); 136 #endif /* HAVE_IFM_DATA */ 137 ncnt += dl->sdl_nlen + 1; 138 } else 139 index = 0; 140 break; 141 142 case RTM_NEWADDR: 143 ifam = (struct ifa_msghdr *)rtm; 144 if (index && ifam->ifam_index != index) 145 abort(); /* this cannot happen */ 146 147 #define RTA_MASKS (RTA_NETMASK | RTA_IFA | RTA_BRD) 148 if (index == 0 || (ifam->ifam_addrs & RTA_MASKS) == 0) 149 break; 150 p = (char *)(ifam + 1); 151 ++icnt; 152 #ifdef HAVE_IFAM_DATA 153 dcnt += sizeof(ifam->ifam_data) + ALIGNBYTES; 154 #endif /* HAVE_IFAM_DATA */ 155 /* Scan to look for length of address */ 156 alen = 0; 157 for (p0 = p, i = 0; i < RTAX_MAX; i++) { 158 if ((RTA_MASKS & ifam->ifam_addrs & (1 << i)) 159 == 0) 160 continue; 161 sa = (struct sockaddr *)p; 162 len = SA_RLEN(sa); 163 if (i == RTAX_IFA) { 164 alen = len; 165 break; 166 } 167 p += len; 168 } 169 for (p = p0, i = 0; i < RTAX_MAX; i++) { 170 if ((RTA_MASKS & ifam->ifam_addrs & (1 << i)) 171 == 0) 172 continue; 173 sa = (struct sockaddr *)p; 174 len = SA_RLEN(sa); 175 if (i == RTAX_NETMASK && SA_LEN(sa) == 0) 176 dcnt += alen; 177 else 178 dcnt += len; 179 p += len; 180 } 181 break; 182 } 183 } 184 #else /* NET_RT_IFLIST */ 185 ifc.ifc_buf = buf; 186 ifc.ifc_len = sizeof(buf); 187 188 if ((sock = socket(AF_INET, SOCK_STREAM, 0)) < 0) 189 return (-1); 190 i = ioctl(sock, SIOCGIFCONF, (char *)&ifc); 191 close(sock); 192 if (i < 0) 193 return (-1); 194 195 ifr = ifc.ifc_req; 196 lifr = (struct ifreq *)&ifc.ifc_buf[ifc.ifc_len]; 197 198 while (ifr < lifr) { 199 struct sockaddr *sa; 200 201 sa = &ifr->ifr_addr; 202 ++icnt; 203 dcnt += SA_RLEN(sa); 204 ncnt += sizeof(ifr->ifr_name) + 1; 205 206 ifr = (struct ifreq *)(((char *)sa) + SA_LEN(sa)); 207 } 208 #endif /* NET_RT_IFLIST */ 209 210 if (icnt + dcnt + ncnt == 1) { 211 *pif = NULL; 212 free(buf); 213 return (0); 214 } 215 data = malloc(sizeof(struct ifaddrs) * icnt + dcnt + ncnt); 216 if (data == NULL) { 217 free(buf); 218 return(-1); 219 } 220 221 ifa = (struct ifaddrs *)data; 222 data += sizeof(struct ifaddrs) * icnt; 223 names = data + dcnt; 224 225 memset(ifa, 0, sizeof(struct ifaddrs) * icnt); 226 ift = ifa; 227 228 #ifdef NET_RT_IFLIST 229 index = 0; 230 for (next = buf; next < buf + needed; next += rtm->rtm_msglen) { 231 rtm = (struct rt_msghdr *)next; 232 if (rtm->rtm_version != RTM_VERSION) 233 continue; 234 switch (rtm->rtm_type) { 235 case RTM_IFINFO: 236 ifm = (struct if_msghdr *)rtm; 237 if (ifm->ifm_addrs & RTA_IFP) { 238 index = ifm->ifm_index; 239 dl = (struct sockaddr_dl *)(ifm + 1); 240 241 cif = ift; 242 ift->ifa_name = names; 243 ift->ifa_flags = (int)ifm->ifm_flags; 244 memcpy(names, dl->sdl_data, dl->sdl_nlen); 245 names[dl->sdl_nlen] = 0; 246 names += dl->sdl_nlen + 1; 247 248 ift->ifa_addr = (struct sockaddr *)data; 249 memcpy(data, dl, SA_LEN((struct sockaddr *)dl)); 250 data += SA_RLEN((struct sockaddr *)dl); 251 252 #ifdef HAVE_IFM_DATA 253 /* ifm_data needs to be aligned */ 254 ift->ifa_data = data = (void *)ALIGN(data); 255 memcpy(data, &ifm->ifm_data, sizeof(ifm->ifm_data)); 256 data += sizeof(ifm->ifm_data); 257 #else /* HAVE_IFM_DATA */ 258 ift->ifa_data = NULL; 259 #endif /* HAVE_IFM_DATA */ 260 261 ift = (ift->ifa_next = ift + 1); 262 } else 263 index = 0; 264 break; 265 266 case RTM_NEWADDR: 267 ifam = (struct ifa_msghdr *)rtm; 268 if (index && ifam->ifam_index != index) 269 abort(); /* this cannot happen */ 270 271 if (index == 0 || (ifam->ifam_addrs & RTA_MASKS) == 0) 272 break; 273 ift->ifa_name = cif->ifa_name; 274 ift->ifa_flags = cif->ifa_flags; 275 ift->ifa_data = NULL; 276 p = (char *)(ifam + 1); 277 /* Scan to look for length of address */ 278 alen = 0; 279 for (p0 = p, i = 0; i < RTAX_MAX; i++) { 280 if ((RTA_MASKS & ifam->ifam_addrs & (1 << i)) 281 == 0) 282 continue; 283 sa = (struct sockaddr *)p; 284 len = SA_RLEN(sa); 285 if (i == RTAX_IFA) { 286 alen = len; 287 break; 288 } 289 p += len; 290 } 291 for (p = p0, i = 0; i < RTAX_MAX; i++) { 292 if ((RTA_MASKS & ifam->ifam_addrs & (1 << i)) 293 == 0) 294 continue; 295 sa = (struct sockaddr *)p; 296 len = SA_RLEN(sa); 297 switch (i) { 298 case RTAX_IFA: 299 ift->ifa_addr = (struct sockaddr *)data; 300 memcpy(data, p, len); 301 data += len; 302 break; 303 304 case RTAX_NETMASK: 305 ift->ifa_netmask = 306 (struct sockaddr *)data; 307 if (SA_LEN(sa) == 0) { 308 memset(data, 0, alen); 309 data += alen; 310 break; 311 } 312 memcpy(data, p, len); 313 data += len; 314 break; 315 316 case RTAX_BRD: 317 ift->ifa_broadaddr = 318 (struct sockaddr *)data; 319 memcpy(data, p, len); 320 data += len; 321 break; 322 } 323 p += len; 324 } 325 326 #ifdef HAVE_IFAM_DATA 327 /* ifam_data needs to be aligned */ 328 ift->ifa_data = data = (void *)ALIGN(data); 329 memcpy(data, &ifam->ifam_data, sizeof(ifam->ifam_data)); 330 data += sizeof(ifam->ifam_data); 331 #endif /* HAVE_IFAM_DATA */ 332 333 ift = (ift->ifa_next = ift + 1); 334 break; 335 } 336 } 337 338 free(buf); 339 #else /* NET_RT_IFLIST */ 340 ifr = ifc.ifc_req; 341 lifr = (struct ifreq *)&ifc.ifc_buf[ifc.ifc_len]; 342 343 while (ifr < lifr) { 344 struct sockaddr *sa; 345 346 ift->ifa_name = names; 347 names[sizeof(ifr->ifr_name)] = 0; 348 strncpy(names, ifr->ifr_name, sizeof(ifr->ifr_name)); 349 while (*names++) 350 ; 351 352 ift->ifa_addr = (struct sockaddr *)data; 353 sa = &ifr->ifr_addr; 354 memcpy(data, sa, SA_LEN(sa)); 355 data += SA_RLEN(sa); 356 357 ifr = (struct ifreq *)(((char *)sa) + SA_LEN(sa)); 358 ift = (ift->ifa_next = ift + 1); 359 } 360 #endif /* NET_RT_IFLIST */ 361 if (--ift >= ifa) { 362 ift->ifa_next = NULL; 363 *pif = ifa; 364 } else { 365 *pif = NULL; 366 free(ifa); 367 } 368 return (0); 369 } 370