1/* 2 * Copyright (C) 2004 Internet Systems Consortium, Inc. ("ISC") 3 * Copyright (C) 1999-2003 Internet Software Consortium. 4 * 5 * Permission to use, copy, modify, and distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH 10 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY 11 * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, 12 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM 13 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE 14 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR 15 * PERFORMANCE OF THIS SOFTWARE. 16 */ 17 18/* $Id: ifiter_sysctl.c,v 1.14.12.7 2004/03/08 09:04:56 marka Exp $ */ 19 20/* 21 * Obtain the list of network interfaces using sysctl. 22 * See TCP/IP Illustrated Volume 2, sections 19.8, 19.14, 23 * and 19.16. 24 */ 25 26#include <sys/param.h> 27#include <sys/sysctl.h> 28 29#include <net/route.h> 30#include <net/if_dl.h> 31 32/* XXX what about Alpha? */ 33#ifdef sgi 34#define ROUNDUP(a) ((a) > 0 ? \ 35 (1 + (((a) - 1) | (sizeof(__uint64_t) - 1))) : \ 36 sizeof(__uint64_t)) 37#else 38#define ROUNDUP(a) ((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) \ 39 : sizeof(long)) 40#endif 41 42#define IFITER_MAGIC ISC_MAGIC('I', 'F', 'I', 'S') 43#define VALID_IFITER(t) ISC_MAGIC_VALID(t, IFITER_MAGIC) 44 45struct isc_interfaceiter { 46 unsigned int magic; /* Magic number. */ 47 isc_mem_t *mctx; 48 void *buf; /* Buffer for sysctl data. */ 49 unsigned int bufsize; /* Bytes allocated. */ 50 unsigned int bufused; /* Bytes used. */ 51 unsigned int pos; /* Current offset in 52 sysctl data. */ 53 isc_interface_t current; /* Current interface data. */ 54 isc_result_t result; /* Last result code. */ 55}; 56 57static int mib[6] = { 58 CTL_NET, 59 PF_ROUTE, 60 0, 61 0, /* Any address family. */ 62 NET_RT_IFLIST, 63 0 /* Flags. */ 64}; 65 66isc_result_t 67isc_interfaceiter_create(isc_mem_t *mctx, isc_interfaceiter_t **iterp) { 68 isc_interfaceiter_t *iter; 69 isc_result_t result; 70 size_t bufsize; 71 size_t bufused; 72 char strbuf[ISC_STRERRORSIZE]; 73 74 REQUIRE(iterp != NULL); 75 REQUIRE(*iterp == NULL); 76 77 iter = isc_mem_get(mctx, sizeof(*iter)); 78 if (iter == NULL) 79 return (ISC_R_NOMEMORY); 80 81 iter->mctx = mctx; 82 iter->buf = 0; 83 84 /* 85 * Determine the amount of memory needed. 86 */ 87 bufsize = 0; 88 if (sysctl(mib, 6, NULL, &bufsize, NULL, (size_t) 0) < 0) { 89 isc__strerror(errno, strbuf, sizeof(strbuf)); 90 UNEXPECTED_ERROR(__FILE__, __LINE__, 91 isc_msgcat_get(isc_msgcat, 92 ISC_MSGSET_IFITERSYSCTL, 93 ISC_MSG_GETIFLISTSIZE, 94 "getting interface " 95 "list size: sysctl: %s"), 96 strbuf); 97 result = ISC_R_UNEXPECTED; 98 goto failure; 99 } 100 iter->bufsize = bufsize; 101 102 iter->buf = isc_mem_get(iter->mctx, iter->bufsize); 103 if (iter->buf == NULL) { 104 result = ISC_R_NOMEMORY; 105 goto failure; 106 } 107 108 bufused = bufsize; 109 if (sysctl(mib, 6, iter->buf, &bufused, NULL, (size_t) 0) < 0) { 110 isc__strerror(errno, strbuf, sizeof(strbuf)); 111 UNEXPECTED_ERROR(__FILE__, __LINE__, 112 isc_msgcat_get(isc_msgcat, 113 ISC_MSGSET_IFITERSYSCTL, 114 ISC_MSG_GETIFLIST, 115 "getting interface list: " 116 "sysctl: %s"), 117 strbuf); 118 result = ISC_R_UNEXPECTED; 119 goto failure; 120 } 121 iter->bufused = bufused; 122 INSIST(iter->bufused <= iter->bufsize); 123 124 /* 125 * A newly created iterator has an undefined position 126 * until isc_interfaceiter_first() is called. 127 */ 128 iter->pos = (unsigned int) -1; 129 iter->result = ISC_R_FAILURE; 130 131 iter->magic = IFITER_MAGIC; 132 *iterp = iter; 133 return (ISC_R_SUCCESS); 134 135 failure: 136 if (iter->buf != NULL) 137 isc_mem_put(mctx, iter->buf, iter->bufsize); 138 isc_mem_put(mctx, iter, sizeof(*iter)); 139 return (result); 140} 141 142/* 143 * Get information about the current interface to iter->current. 144 * If successful, return ISC_R_SUCCESS. 145 * If the interface has an unsupported address family, 146 * return ISC_R_IGNORE. In case of other failure, 147 * return ISC_R_UNEXPECTED. 148 */ 149 150static isc_result_t 151internal_current(isc_interfaceiter_t *iter) { 152 struct ifa_msghdr *ifam, *ifam_end; 153 154 REQUIRE(VALID_IFITER(iter)); 155 REQUIRE (iter->pos < (unsigned int) iter->bufused); 156 157 ifam = (struct ifa_msghdr *) ((char *) iter->buf + iter->pos); 158 ifam_end = (struct ifa_msghdr *) ((char *) iter->buf + iter->bufused); 159 160 if (ifam->ifam_type == RTM_IFINFO) { 161 struct if_msghdr *ifm = (struct if_msghdr *) ifam; 162 struct sockaddr_dl *sdl = (struct sockaddr_dl *) (ifm + 1); 163 unsigned int namelen; 164 165 memset(&iter->current, 0, sizeof(iter->current)); 166 167 namelen = sdl->sdl_nlen; 168 if (namelen > sizeof(iter->current.name) - 1) 169 namelen = sizeof(iter->current.name) - 1; 170 171 memset(iter->current.name, 0, sizeof(iter->current.name)); 172 memcpy(iter->current.name, sdl->sdl_data, namelen); 173 174 iter->current.flags = 0; 175 176 if ((ifam->ifam_flags & IFF_UP) != 0) 177 iter->current.flags |= INTERFACE_F_UP; 178 179 if ((ifam->ifam_flags & IFF_POINTOPOINT) != 0) 180 iter->current.flags |= INTERFACE_F_POINTTOPOINT; 181 182 if ((ifam->ifam_flags & IFF_LOOPBACK) != 0) 183 iter->current.flags |= INTERFACE_F_LOOPBACK; 184 185 if ((ifam->ifam_flags & IFF_BROADCAST) != 0) { 186 iter->current.flags |= INTERFACE_F_BROADCAST; 187 } 188#ifdef IFF_MULTICAST 189 if ((ifam->ifam_flags & IFF_MULTICAST) != 0) { 190 iter->current.flags |= INTERFACE_F_MULTICAST; 191 } 192#endif 193 194 /* 195 * This is not an interface address. 196 * Force another iteration. 197 */ 198 return (ISC_R_IGNORE); 199 } else if (ifam->ifam_type == RTM_NEWADDR) { 200 int i; 201 int family; 202 struct sockaddr *mask_sa = NULL; 203 struct sockaddr *addr_sa = NULL; 204 struct sockaddr *dst_sa = NULL; 205 206 struct sockaddr *sa = (struct sockaddr *)(ifam + 1); 207 family = sa->sa_family; 208 209 for (i = 0; i < RTAX_MAX; i++) 210 { 211 if ((ifam->ifam_addrs & (1 << i)) == 0) 212 continue; 213 214 INSIST(sa < (struct sockaddr *) ifam_end); 215 216 switch (i) { 217 case RTAX_NETMASK: /* Netmask */ 218 mask_sa = sa; 219 break; 220 case RTAX_IFA: /* Interface address */ 221 addr_sa = sa; 222 break; 223 case RTAX_BRD: /* Broadcast or destination address */ 224 dst_sa = sa; 225 break; 226 } 227#ifdef ISC_PLATFORM_HAVESALEN 228 sa = (struct sockaddr *)((char*)(sa) 229 + ROUNDUP(sa->sa_len)); 230#else 231#ifdef sgi 232 /* 233 * Do as the contributed SGI code does. 234 */ 235 sa = (struct sockaddr *)((char*)(sa) 236 + ROUNDUP(_FAKE_SA_LEN_DST(sa))); 237#else 238 /* XXX untested. */ 239 sa = (struct sockaddr *)((char*)(sa) 240 + ROUNDUP(sizeof(struct sockaddr))); 241#endif 242#endif 243 } 244 245 if (addr_sa == NULL) 246 return (ISC_R_IGNORE); 247 248 family = addr_sa->sa_family; 249 if (family != AF_INET && family != AF_INET6) 250 return (ISC_R_IGNORE); 251 252 iter->current.af = family; 253 254 get_addr(family, &iter->current.address, addr_sa, 255 iter->current.name); 256 257 if (mask_sa != NULL) 258 get_addr(family, &iter->current.netmask, mask_sa, 259 iter->current.name); 260 261 if (dst_sa != NULL && 262 (iter->current.flags & INTERFACE_F_POINTTOPOINT) != 0) 263 get_addr(family, &iter->current.dstaddress, dst_sa, 264 iter->current.name); 265 266 if (dst_sa != NULL && 267 (iter->current.flags & INTERFACE_F_BROADCAST) != 0) 268 get_addr(family, &iter->current.broadcast, dst_sa, 269 iter->current.name); 270 271 272 return (ISC_R_SUCCESS); 273 } else { 274 printf(isc_msgcat_get(isc_msgcat, ISC_MSGSET_IFITERSYSCTL, 275 ISC_MSG_UNEXPECTEDTYPE, 276 "warning: unexpected interface list " 277 "message type\n")); 278 return (ISC_R_IGNORE); 279 } 280} 281 282/* 283 * Step the iterator to the next interface. Unlike 284 * isc_interfaceiter_next(), this may leave the iterator 285 * positioned on an interface that will ultimately 286 * be ignored. Return ISC_R_NOMORE if there are no more 287 * interfaces, otherwise ISC_R_SUCCESS. 288 */ 289static isc_result_t 290internal_next(isc_interfaceiter_t *iter) { 291 struct ifa_msghdr *ifam; 292 REQUIRE (iter->pos < (unsigned int) iter->bufused); 293 294 ifam = (struct ifa_msghdr *) ((char *) iter->buf + iter->pos); 295 296 iter->pos += ifam->ifam_msglen; 297 298 if (iter->pos >= iter->bufused) 299 return (ISC_R_NOMORE); 300 301 return (ISC_R_SUCCESS); 302} 303 304static void 305internal_destroy(isc_interfaceiter_t *iter) { 306 UNUSED(iter); /* Unused. */ 307 /* 308 * Do nothing. 309 */ 310} 311 312static 313void internal_first(isc_interfaceiter_t *iter) { 314 iter->pos = 0; 315} 316