/* $NetBSD: ifiter_sysctl.c,v 1.2 2024/08/18 20:47:16 christos Exp $ */ /* * Copyright (C) 2004, 2005, 2007 Internet Systems Consortium, Inc. ("ISC") * Copyright (C) 1999-2003 Internet Software Consortium. * * Permission to use, copy, modify, and/or distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR * PERFORMANCE OF THIS SOFTWARE. */ /* Id: ifiter_sysctl.c,v 1.25 2007/06/19 23:47:18 tbox Exp */ /*! \file * \brief * Obtain the list of network interfaces using sysctl. * See TCP/IP Illustrated Volume 2, sections 19.8, 19.14, * and 19.16. */ #include #include #include #include /* XXX what about Alpha? */ #ifdef sgi #define ROUNDUP(a) ((a) > 0 ? \ (1 + (((a) - 1) | (sizeof(__uint64_t) - 1))) : \ sizeof(__uint64_t)) #else #define ROUNDUP(a) ((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) \ : sizeof(long)) #endif #define IFITER_MAGIC ISC_MAGIC('I', 'F', 'I', 'S') #define VALID_IFITER(t) ISC_MAGIC_VALID(t, IFITER_MAGIC) struct isc_interfaceiter { unsigned int magic; /* Magic number. */ isc_mem_t *mctx; void *buf; /* Buffer for sysctl data. */ unsigned int bufsize; /* Bytes allocated. */ unsigned int bufused; /* Bytes used. */ unsigned int pos; /* Current offset in sysctl data. */ isc_interface_t current; /* Current interface data. */ isc_result_t result; /* Last result code. */ }; static int mib[6] = { CTL_NET, PF_ROUTE, 0, 0, /* Any address family. */ NET_RT_IFLIST, 0 /* Flags. */ }; isc_result_t isc_interfaceiter_create(isc_mem_t *mctx, isc_interfaceiter_t **iterp) { isc_interfaceiter_t *iter; isc_result_t result; size_t bufsize; size_t bufused; char strbuf[ISC_STRERRORSIZE]; REQUIRE(mctx != NULL); REQUIRE(iterp != NULL); REQUIRE(*iterp == NULL); iter = isc_mem_get(mctx, sizeof(*iter)); if (iter == NULL) return (ISC_R_NOMEMORY); iter->mctx = mctx; iter->buf = 0; /* * Determine the amount of memory needed. */ bufsize = 0; if (sysctl(mib, 6, NULL, &bufsize, NULL, (size_t) 0) < 0) { isc__strerror(errno, strbuf, sizeof(strbuf)); UNEXPECTED_ERROR(__FILE__, __LINE__, isc_msgcat_get(isc_msgcat, ISC_MSGSET_IFITERSYSCTL, ISC_MSG_GETIFLISTSIZE, "getting interface " "list size: sysctl: %s"), strbuf); result = ISC_R_UNEXPECTED; goto failure; } iter->bufsize = bufsize; iter->buf = isc_mem_get(iter->mctx, iter->bufsize); if (iter->buf == NULL) { result = ISC_R_NOMEMORY; goto failure; } bufused = bufsize; if (sysctl(mib, 6, iter->buf, &bufused, NULL, (size_t) 0) < 0) { isc__strerror(errno, strbuf, sizeof(strbuf)); UNEXPECTED_ERROR(__FILE__, __LINE__, isc_msgcat_get(isc_msgcat, ISC_MSGSET_IFITERSYSCTL, ISC_MSG_GETIFLIST, "getting interface list: " "sysctl: %s"), strbuf); result = ISC_R_UNEXPECTED; goto failure; } iter->bufused = bufused; INSIST(iter->bufused <= iter->bufsize); /* * A newly created iterator has an undefined position * until isc_interfaceiter_first() is called. */ iter->pos = (unsigned int) -1; iter->result = ISC_R_FAILURE; iter->magic = IFITER_MAGIC; *iterp = iter; return (ISC_R_SUCCESS); failure: if (iter->buf != NULL) isc_mem_put(mctx, iter->buf, iter->bufsize); isc_mem_put(mctx, iter, sizeof(*iter)); return (result); } /* * Get information about the current interface to iter->current. * If successful, return ISC_R_SUCCESS. * If the interface has an unsupported address family, * return ISC_R_IGNORE. In case of other failure, * return ISC_R_UNEXPECTED. */ static isc_result_t internal_current(isc_interfaceiter_t *iter) { struct ifa_msghdr *ifam, *ifam_end; REQUIRE(VALID_IFITER(iter)); REQUIRE (iter->pos < (unsigned int) iter->bufused); ifam = (struct ifa_msghdr *) ((char *) iter->buf + iter->pos); ifam_end = (struct ifa_msghdr *) ((char *) iter->buf + iter->bufused); // Skip wrong RTM version headers if (ifam->ifam_version != RTM_VERSION) return (ISC_R_IGNORE); if (ifam->ifam_type == RTM_IFINFO) { struct if_msghdr *ifm = (struct if_msghdr *) ifam; struct sockaddr_dl *sdl = (struct sockaddr_dl *) (ifm + 1); unsigned int namelen; memset(&iter->current, 0, sizeof(iter->current)); iter->current.ifindex = sdl->sdl_index; namelen = sdl->sdl_nlen; if (namelen > sizeof(iter->current.name) - 1) namelen = sizeof(iter->current.name) - 1; memset(iter->current.name, 0, sizeof(iter->current.name)); memcpy(iter->current.name, sdl->sdl_data, namelen); iter->current.flags = 0; if ((ifam->ifam_flags & IFF_UP) != 0) iter->current.flags |= INTERFACE_F_UP; if ((ifam->ifam_flags & IFF_POINTOPOINT) != 0) iter->current.flags |= INTERFACE_F_POINTTOPOINT; if ((ifam->ifam_flags & IFF_LOOPBACK) != 0) iter->current.flags |= INTERFACE_F_LOOPBACK; if ((ifam->ifam_flags & IFF_BROADCAST) != 0) iter->current.flags |= INTERFACE_F_BROADCAST; #ifdef IFF_MULTICAST if ((ifam->ifam_flags & IFF_MULTICAST) != 0) iter->current.flags |= INTERFACE_F_MULTICAST; #endif /* * This is not an interface address. * Force another iteration. */ return (ISC_R_IGNORE); } else if (ifam->ifam_type == RTM_NEWADDR) { int i; int family; struct sockaddr *mask_sa = NULL; struct sockaddr *addr_sa = NULL; struct sockaddr *dst_sa = NULL; struct sockaddr *sa = (struct sockaddr *)(ifam + 1); family = sa->sa_family; for (i = 0; i < RTAX_MAX; i++) { if ((ifam->ifam_addrs & (1 << i)) == 0) continue; INSIST(sa < (struct sockaddr *) ifam_end); switch (i) { case RTAX_NETMASK: /* Netmask */ mask_sa = sa; break; case RTAX_IFA: /* Interface address */ addr_sa = sa; break; case RTAX_BRD: /* Broadcast or destination address */ dst_sa = sa; break; } #ifdef ISC_PLATFORM_HAVESALEN sa = (struct sockaddr *)((char*)(sa) + ROUNDUP(sa->sa_len)); #else #ifdef sgi /* * Do as the contributed SGI code does. */ sa = (struct sockaddr *)((char*)(sa) + ROUNDUP(_FAKE_SA_LEN_DST(sa))); #else /* XXX untested. */ sa = (struct sockaddr *)((char*)(sa) + ROUNDUP(sizeof(struct sockaddr))); #endif #endif } if (addr_sa == NULL) return (ISC_R_IGNORE); family = addr_sa->sa_family; if (family != AF_INET && family != AF_INET6) return (ISC_R_IGNORE); iter->current.af = family; get_addr(family, &iter->current.address, addr_sa, iter->current.name); if (mask_sa != NULL) get_addr(family, &iter->current.netmask, mask_sa, iter->current.name); if (dst_sa != NULL && (iter->current.flags & INTERFACE_F_POINTTOPOINT) != 0) get_addr(family, &iter->current.dstaddress, dst_sa, iter->current.name); if (dst_sa != NULL && (iter->current.flags & INTERFACE_F_BROADCAST) != 0) get_addr(family, &iter->current.broadcast, dst_sa, iter->current.name); return (ISC_R_SUCCESS); } else { printf("%s", isc_msgcat_get(isc_msgcat, ISC_MSGSET_IFITERSYSCTL, ISC_MSG_UNEXPECTEDTYPE, "warning: unexpected interface " "list message type\n")); return (ISC_R_IGNORE); } } /* * Step the iterator to the next interface. Unlike * isc_interfaceiter_next(), this may leave the iterator * positioned on an interface that will ultimately * be ignored. Return ISC_R_NOMORE if there are no more * interfaces, otherwise ISC_R_SUCCESS. */ static isc_result_t internal_next(isc_interfaceiter_t *iter) { struct ifa_msghdr *ifam; REQUIRE (iter->pos < (unsigned int) iter->bufused); ifam = (struct ifa_msghdr *) ((char *) iter->buf + iter->pos); iter->pos += ifam->ifam_msglen; if (iter->pos >= iter->bufused) return (ISC_R_NOMORE); return (ISC_R_SUCCESS); } static void internal_destroy(isc_interfaceiter_t *iter) { UNUSED(iter); /* Unused. */ /* * Do nothing. */ } static void internal_first(isc_interfaceiter_t *iter) { iter->pos = 0; }