lib/socket/interfaces.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    return a list of network interfaces
   4    Copyright (C) Andrew Tridgell 1998
   5    Copyright (C) Jeremy Allison 2007
   6    Copyright (C) Jelmer Vernooij 2007
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22
  23 #include "includes.h"
  24 #include "system/network.h"
  25 #include "interfaces.h"
  26 #include "lib/util/tsort.h"
  27 #include "librpc/gen_ndr/ioctl.h"
  28
  29 #ifdef HAVE_ETHTOOL
  30 #include "linux/sockios.h"
  31 #include "linux/ethtool.h"
  32 #endif
  33
  34 /****************************************************************************
  35  Create a struct sockaddr_storage with the netmask bits set to 1.
  36 ****************************************************************************/
  37
  38 bool make_netmask(struct sockaddr_storage *pss_out,
  39                         const struct sockaddr_storage *pss_in,
  40                         unsigned long masklen)
  41 {
  42         *pss_out = *pss_in;
  43         /* Now apply masklen bits of mask. */
  44 #if defined(HAVE_IPV6)
  45         if (pss_in->ss_family == AF_INET6) {
  46                 char *p = (char *)&((struct sockaddr_in6 *)pss_out)->sin6_addr;
  47                 unsigned int i;
  48
  49                 if (masklen > 128) {
  50                         return false;
  51                 }
  52                 for (i = 0; masklen >= 8; masklen -= 8, i++) {
  53                         *p++ = 0xff;
  54                 }
  55                 /* Deal with the partial byte. */
  56                 *p++ &= (0xff & ~(0xff>>masklen));
  57                 i++;
  58                 for (;i < sizeof(struct in6_addr); i++) {
  59                         *p++ = '\0';
  60                 }
  61                 return true;
  62         }
  63 #endif
  64         if (pss_in->ss_family == AF_INET) {
  65                 if (masklen > 32) {
  66                         return false;
  67                 }
  68                 ((struct sockaddr_in *)pss_out)->sin_addr.s_addr =
  69                         htonl(((0xFFFFFFFFL >> masklen) ^ 0xFFFFFFFFL));
  70                 return true;
  71         }
  72         return false;
  73 }
  74
  75 /****************************************************************************
  76  Create a struct sockaddr_storage set to the broadcast or network adress from
  77  an incoming sockaddr_storage.
  78 ****************************************************************************/
  79
  80 static void make_bcast_or_net(struct sockaddr_storage *pss_out,
  81                         const struct sockaddr_storage *pss_in,
  82                         const struct sockaddr_storage *nmask,
  83                         bool make_bcast_p)
  84 {
  85         unsigned int i = 0, len = 0;
  86         const char *pmask = NULL;
  87         char *p = NULL;
  88         *pss_out = *pss_in;
  89
  90         /* Set all zero netmask bits to 1. */
  91 #if defined(HAVE_IPV6)
  92         if (pss_in->ss_family == AF_INET6) {
  93                 p = (char *)&((struct sockaddr_in6 *)pss_out)->sin6_addr;
  94                 pmask = (const char *)&((const struct sockaddr_in6 *)nmask)->sin6_addr;
  95                 len = 16;
  96         }
  97 #endif
  98         if (pss_in->ss_family == AF_INET) {
  99                 p = (char *)&((struct sockaddr_in *)pss_out)->sin_addr;
 100                 pmask = (const char *)&((const struct sockaddr_in *)nmask)->sin_addr;
 101                 len = 4;
 102         }
 103
 104         for (i = 0; i < len; i++, p++, pmask++) {
 105                 if (make_bcast_p) {
 106                         *p = (*p & *pmask) | (*pmask ^ 0xff);
 107                 } else {
 108                         /* make_net */
 109                         *p = (*p & *pmask);
 110                 }
 111         }
 112 }
 113
 114 void make_bcast(struct sockaddr_storage *pss_out,
 115                         const struct sockaddr_storage *pss_in,
 116                         const struct sockaddr_storage *nmask)
 117 {
 118         make_bcast_or_net(pss_out, pss_in, nmask, true);
 119 }
 120
 121 void make_net(struct sockaddr_storage *pss_out,
 122                         const struct sockaddr_storage *pss_in,
 123                         const struct sockaddr_storage *nmask)
 124 {
 125         make_bcast_or_net(pss_out, pss_in, nmask, false);
 126 }
 127
 128 #ifdef HAVE_ETHTOOL
 129 static void query_iface_speed_from_name(const char *name, uint64_t *speed)
 130 {
 131         int ret = 0;
 132         struct ethtool_cmd ecmd;
 133         struct ethtool_value edata;
 134         struct ifreq ifr;
 135         int fd;
 136
 137         fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
 138         if (fd == -1) {
 139                 DBG_ERR("Failed to open socket.");
 140                 return;
 141         }
 142
 143         strncpy(ifr.ifr_name, name, IF_NAMESIZE);
 144
 145         ifr.ifr_data = (void *)&edata;
 146         edata.cmd = ETHTOOL_GLINK;
 147         ret = ioctl(fd, SIOCETHTOOL, &ifr);
 148         if (ret == -1) {
 149                 goto done;
 150         }
 151         if (edata.data == 0) {
 152                 /* no link detected */
 153                 *speed = 0;
 154                 goto done;
 155         }
 156
 157         ifr.ifr_data = (void *)&ecmd;
 158         ecmd.cmd = ETHTOOL_GSET;
 159         ret = ioctl(fd, SIOCETHTOOL, &ifr);
 160         if (ret == -1) {
 161                 goto done;
 162         }
 163         *speed = ((uint64_t)ethtool_cmd_speed(&ecmd)) * 1000 * 1000;
 164
 165 done:
 166         (void)close(fd);
 167 }
 168 #endif
 169
 170 /****************************************************************************
 171  Try the "standard" getifaddrs/freeifaddrs interfaces.
 172  Also gets IPv6 interfaces.
 173 ****************************************************************************/
 174
 175 /****************************************************************************
 176  Get the netmask address for a local interface.
 177 ****************************************************************************/
 178
 179 static int _get_interfaces(TALLOC_CTX *mem_ctx, struct iface_struct **pifaces)
 180 {
 181         struct iface_struct *ifaces;
 182         struct ifaddrs *iflist = NULL;
 183         struct ifaddrs *ifptr = NULL;
 184         int count;
 185         int total = 0;
 186         size_t copy_size;
 187         uint64_t if_speed = 1000 * 1000 * 1000; /* 1GBit */
 188
 189         if (getifaddrs(&iflist) < 0) {
 190                 return -1;
 191         }
 192
 193         count = 0;
 194         for (ifptr = iflist; ifptr != NULL; ifptr = ifptr->ifa_next) {
 195                 if (!ifptr->ifa_addr || !ifptr->ifa_netmask) {
 196                         continue;
 197                 }
 198                 if (!(ifptr->ifa_flags & IFF_UP)) {
 199                         continue;
 200                 }
 201                 count += 1;
 202         }
 203
 204         ifaces = talloc_array(mem_ctx, struct iface_struct, count);
 205         if (ifaces == NULL) {
 206                 errno = ENOMEM;
 207                 return -1;
 208         }
 209
 210         /* Loop through interfaces, looking for given IP address */
 211         for (ifptr = iflist; ifptr != NULL; ifptr = ifptr->ifa_next) {
 212
 213                 if (!ifptr->ifa_addr || !ifptr->ifa_netmask) {
 214                         continue;
 215                 }
 216
 217                 /* Check the interface is up. */
 218                 if (!(ifptr->ifa_flags & IFF_UP)) {
 219                         continue;
 220                 }
 221
 222                 memset(&ifaces[total], '\0', sizeof(ifaces[total]));
 223
 224                 copy_size = sizeof(struct sockaddr_in);
 225
 226                 ifaces[total].flags = ifptr->ifa_flags;
 227
 228 #if defined(HAVE_IPV6)
 229                 if (ifptr->ifa_addr->sa_family == AF_INET6) {
 230                         copy_size = sizeof(struct sockaddr_in6);
 231                 }
 232 #endif
 233
 234                 memcpy(&ifaces[total].ip, ifptr->ifa_addr, copy_size);
 235                 memcpy(&ifaces[total].netmask, ifptr->ifa_netmask, copy_size);
 236
 237                 /* calculate broadcast address */
 238 #if defined(HAVE_IPV6)
 239                 if (ifptr->ifa_addr->sa_family == AF_INET6) {
 240                         struct sockaddr_in6 *sin6 =
 241                                 (struct sockaddr_in6 *)ifptr->ifa_addr;
 242                         struct in6_addr *in6 =
 243                                 (struct in6_addr *)&sin6->sin6_addr;
 244
 245                         if (IN6_IS_ADDR_LINKLOCAL(in6) || IN6_IS_ADDR_V4COMPAT(in6)) {
 246                                 continue;
 247                         }
 248                         /* IPv6 does not have broadcast it uses multicast. */
 249                         memset(&ifaces[total].bcast, '\0', copy_size);
 250                 } else
 251 #endif
 252                 if (ifaces[total].flags & (IFF_BROADCAST|IFF_LOOPBACK)) {
 253                         make_bcast(&ifaces[total].bcast,
 254                                 &ifaces[total].ip,
 255                                 &ifaces[total].netmask);
 256                 } else if ((ifaces[total].flags & IFF_POINTOPOINT) &&
 257                                ifptr->ifa_dstaddr ) {
 258                         memcpy(&ifaces[total].bcast,
 259                                 ifptr->ifa_dstaddr,
 260                                 copy_size);
 261                 } else {
 262                         continue;
 263                 }
 264
 265                 ifaces[total].if_index = if_nametoindex(ifptr->ifa_name);
 266                 if (ifaces[total].if_index == 0) {
 267                         DBG_ERR("Failed to retrieve interface index for '%s': "
 268                                 "%s\n", ifptr->ifa_name, strerror(errno));
 269                 }
 270
 271 #ifdef HAVE_ETHTOOL
 272                 query_iface_speed_from_name(ifptr->ifa_name, &if_speed);
 273 #endif
 274                 ifaces[total].linkspeed = if_speed;
 275                 ifaces[total].capability = FSCTL_NET_IFACE_NONE_CAPABLE;
 276
 277                 if (strlcpy(ifaces[total].name, ifptr->ifa_name,
 278                         sizeof(ifaces[total].name)) >=
 279                                 sizeof(ifaces[total].name)) {
 280                         /* Truncation ! Ignore. */
 281                         continue;
 282                 }
 283                 total++;
 284         }
 285
 286         freeifaddrs(iflist);
 287
 288         *pifaces = ifaces;
 289         return total;
 290 }
 291
 292 static int iface_comp(struct iface_struct *i1, struct iface_struct *i2)
 293 {
 294         int r;
 295
 296 #if defined(HAVE_IPV6)
 297         /*
 298          * If we have IPv6 - sort these interfaces lower
 299          * than any IPv4 ones.
 300          */
 301         if (i1->ip.ss_family == AF_INET6 &&
 302                         i2->ip.ss_family == AF_INET) {
 303                 return -1;
 304         } else if (i1->ip.ss_family == AF_INET &&
 305                         i2->ip.ss_family == AF_INET6) {
 306                 return 1;
 307         }
 308
 309         if (i1->ip.ss_family == AF_INET6) {
 310                 struct sockaddr_in6 *s1 = (struct sockaddr_in6 *)&i1->ip;
 311                 struct sockaddr_in6 *s2 = (struct sockaddr_in6 *)&i2->ip;
 312
 313                 r = memcmp(&s1->sin6_addr,
 314                                 &s2->sin6_addr,
 315                                 sizeof(struct in6_addr));
 316                 if (r) {
 317                         return r;
 318                 }
 319
 320                 s1 = (struct sockaddr_in6 *)&i1->netmask;
 321                 s2 = (struct sockaddr_in6 *)&i2->netmask;
 322
 323                 r = memcmp(&s1->sin6_addr,
 324                                 &s2->sin6_addr,
 325                                 sizeof(struct in6_addr));
 326                 if (r) {
 327                         return r;
 328                 }
 329         }
 330 #endif
 331
 332         /* AIX uses __ss_family instead of ss_family inside of
 333            sockaddr_storage. Instead of trying to figure out which field to
 334            use, we can just cast it to a sockaddr.
 335          */
 336
 337         if (((struct sockaddr *)&i1->ip)->sa_family == AF_INET) {
 338                 struct sockaddr_in *s1 = (struct sockaddr_in *)&i1->ip;
 339                 struct sockaddr_in *s2 = (struct sockaddr_in *)&i2->ip;
 340
 341                 r = ntohl(s1->sin_addr.s_addr) -
 342                         ntohl(s2->sin_addr.s_addr);
 343                 if (r) {
 344                         return r;
 345                 }
 346
 347                 s1 = (struct sockaddr_in *)&i1->netmask;
 348                 s2 = (struct sockaddr_in *)&i2->netmask;
 349
 350                 return ntohl(s1->sin_addr.s_addr) -
 351                         ntohl(s2->sin_addr.s_addr);
 352         }
 353         return 0;
 354 }
 355
 356 /* this wrapper is used to remove duplicates from the interface list generated
 357    above */
 358 int get_interfaces(TALLOC_CTX *mem_ctx, struct iface_struct **pifaces)
 359 {
 360         struct iface_struct *ifaces;
 361         int total, i, j;
 362
 363         total = _get_interfaces(mem_ctx, &ifaces);
 364         if (total <= 0) return total;
 365
 366         /* now we need to remove duplicates */
 367         TYPESAFE_QSORT(ifaces, total, iface_comp);
 368
 369         for (i=1;i<total;) {
 370                 if (iface_comp(&ifaces[i-1], &ifaces[i]) == 0) {
 371                         for (j=i-1;j<total-1;j++) {
 372                                 ifaces[j] = ifaces[j+1];
 373                         }
 374                         total--;
 375                 } else {
 376                         i++;
 377                 }
 378         }
 379
 380         *pifaces = ifaces;
 381         return total;
 382 }