6/contrib/bind9/lib/isc/unix/ifiter_getifaddrs.c

   1 /*
   2  * Copyright (C) 2004, 2007  Internet Systems Consortium, Inc. ("ISC")
   3  * Copyright (C) 2003  Internet Software Consortium.
   4  *
   5  * Permission to use, copy, modify, and/or 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_getifaddrs.c,v 1.2.68.6 2007/08/28 07:19:17 tbox Exp $ */
  19
  20 /*
  21  * Obtain the list of network interfaces using the getifaddrs(3) library.
  22  */
  23
  24 #include <ifaddrs.h>
  25
  26 #define IFITER_MAGIC            ISC_MAGIC('I', 'F', 'I', 'G')
  27 #define VALID_IFITER(t)         ISC_MAGIC_VALID(t, IFITER_MAGIC)
  28
  29 struct isc_interfaceiter {
  30         unsigned int            magic;          /* Magic number. */
  31         isc_mem_t               *mctx;
  32         void                    *buf;           /* (unused) */
  33         unsigned int            bufsize;        /* (always 0) */
  34         struct ifaddrs          *ifaddrs;       /* List of ifaddrs */
  35         struct ifaddrs          *pos;           /* Ptr to current ifaddr */
  36         isc_interface_t         current;        /* Current interface data. */
  37         isc_result_t            result;         /* Last result code. */
  38 };
  39
  40 isc_result_t
  41 isc_interfaceiter_create(isc_mem_t *mctx, isc_interfaceiter_t **iterp) {
  42         isc_interfaceiter_t *iter;
  43         isc_result_t result;
  44         char strbuf[ISC_STRERRORSIZE];
  45
  46         REQUIRE(mctx != NULL);
  47         REQUIRE(iterp != NULL);
  48         REQUIRE(*iterp == NULL);
  49
  50         iter = isc_mem_get(mctx, sizeof(*iter));
  51         if (iter == NULL)
  52                 return (ISC_R_NOMEMORY);
  53
  54         iter->mctx = mctx;
  55         iter->buf = NULL;
  56         iter->bufsize = 0;
  57         iter->ifaddrs = NULL;
  58
  59         if (getifaddrs(&iter->ifaddrs) < 0) {
  60                 isc__strerror(errno, strbuf, sizeof(strbuf));
  61                 UNEXPECTED_ERROR(__FILE__, __LINE__,
  62                                  isc_msgcat_get(isc_msgcat,
  63                                                 ISC_MSGSET_IFITERGETIFADDRS,
  64                                                 ISC_MSG_GETIFADDRS,
  65                                                 "getting interface "
  66                                                 "addresses: getifaddrs: %s"),
  67                                  strbuf);
  68                 result = ISC_R_UNEXPECTED;
  69                 goto failure;
  70         }
  71
  72         /*
  73          * A newly created iterator has an undefined position
  74          * until isc_interfaceiter_first() is called.
  75          */
  76         iter->pos = NULL;
  77         iter->result = ISC_R_FAILURE;
  78
  79         iter->magic = IFITER_MAGIC;
  80         *iterp = iter;
  81         return (ISC_R_SUCCESS);
  82
  83  failure:
  84         if (iter->ifaddrs != NULL) /* just in case */
  85                 freeifaddrs(iter->ifaddrs);
  86         isc_mem_put(mctx, iter, sizeof(*iter));
  87         return (result);
  88 }
  89
  90 /*
  91  * Get information about the current interface to iter->current.
  92  * If successful, return ISC_R_SUCCESS.
  93  * If the interface has an unsupported address family,
  94  * return ISC_R_IGNORE.
  95  */
  96
  97 static isc_result_t
  98 internal_current(isc_interfaceiter_t *iter) {
  99         struct ifaddrs *ifa;
 100         int family;
 101         unsigned int namelen;
 102
 103         REQUIRE(VALID_IFITER(iter));
 104
 105         ifa = iter->pos;
 106
 107         INSIST(ifa != NULL);
 108         INSIST(ifa->ifa_name != NULL);
 109
 110         if (ifa->ifa_addr == NULL)
 111                 return (ISC_R_IGNORE);
 112
 113         family = ifa->ifa_addr->sa_family;
 114         if (family != AF_INET && family != AF_INET6)
 115                 return (ISC_R_IGNORE);
 116
 117         memset(&iter->current, 0, sizeof(iter->current));
 118
 119         namelen = strlen(ifa->ifa_name);
 120         if (namelen > sizeof(iter->current.name) - 1)
 121                 namelen = sizeof(iter->current.name) - 1;
 122
 123         memset(iter->current.name, 0, sizeof(iter->current.name));
 124         memcpy(iter->current.name, ifa->ifa_name, namelen);
 125
 126         iter->current.flags = 0;
 127
 128         if ((ifa->ifa_flags & IFF_UP) != 0)
 129                 iter->current.flags |= INTERFACE_F_UP;
 130
 131         if ((ifa->ifa_flags & IFF_POINTOPOINT) != 0)
 132                 iter->current.flags |= INTERFACE_F_POINTTOPOINT;
 133
 134         if ((ifa->ifa_flags & IFF_LOOPBACK) != 0)
 135                 iter->current.flags |= INTERFACE_F_LOOPBACK;
 136
 137         iter->current.af = family;
 138
 139         get_addr(family, &iter->current.address, ifa->ifa_addr, ifa->ifa_name);
 140
 141         if (ifa->ifa_netmask != NULL)
 142                 get_addr(family, &iter->current.netmask, ifa->ifa_netmask,
 143                          ifa->ifa_name);
 144
 145         if (ifa->ifa_dstaddr != NULL &&
 146             (iter->current.flags & IFF_POINTOPOINT) != 0)
 147                 get_addr(family, &iter->current.dstaddress, ifa->ifa_dstaddr,
 148                          ifa->ifa_name);
 149
 150         return (ISC_R_SUCCESS);
 151 }
 152
 153 /*
 154  * Step the iterator to the next interface.  Unlike
 155  * isc_interfaceiter_next(), this may leave the iterator
 156  * positioned on an interface that will ultimately
 157  * be ignored.  Return ISC_R_NOMORE if there are no more
 158  * interfaces, otherwise ISC_R_SUCCESS.
 159  */
 160 static isc_result_t
 161 internal_next(isc_interfaceiter_t *iter) {
 162         iter->pos = iter->pos->ifa_next;
 163
 164         if (iter->pos == NULL)
 165                 return (ISC_R_NOMORE);
 166
 167         return (ISC_R_SUCCESS);
 168 }
 169
 170 static void
 171 internal_destroy(isc_interfaceiter_t *iter) {
 172         if (iter->ifaddrs)
 173                 freeifaddrs(iter->ifaddrs);
 174         iter->ifaddrs = NULL;
 175 }
 176
 177 static
 178 void internal_first(isc_interfaceiter_t *iter) {
 179         iter->pos = iter->ifaddrs;
 180 }