src/shared/socket-util.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2010 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU Lesser General Public License as published by
  10   the Free Software Foundation; either version 2.1 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   Lesser General Public License for more details.
  17
  18   You should have received a copy of the GNU Lesser General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <assert.h>
  23 #include <string.h>
  24 #include <unistd.h>
  25 #include <errno.h>
  26 #include <stdlib.h>
  27 #include <arpa/inet.h>
  28 #include <stdio.h>
  29 #include <net/if.h>
  30 #include <sys/types.h>
  31 #include <sys/stat.h>
  32 #include <stddef.h>
  33 #include <sys/ioctl.h>
  34 #include <netdb.h>
  35
  36 #include "macro.h"
  37 #include "util.h"
  38 #include "mkdir.h"
  39 #include "path-util.h"
  40 #include "socket-util.h"
  41 #include "missing.h"
  42 #include "fileio.h"
  43
  44 int socket_address_parse(SocketAddress *a, const char *s) {
  45         char *e, *n;
  46         unsigned u;
  47         int r;
  48
  49         assert(a);
  50         assert(s);
  51
  52         zero(*a);
  53         a->type = SOCK_STREAM;
  54
  55         if (*s == '[') {
  56                 /* IPv6 in [x:.....:z]:p notation */
  57
  58                 if (!socket_ipv6_is_supported()) {
  59                         log_warning("Binding to IPv6 address not available since kernel does not support IPv6.");
  60                         return -EAFNOSUPPORT;
  61                 }
  62
  63                 e = strchr(s+1, ']');
  64                 if (!e)
  65                         return -EINVAL;
  66
  67                 n = strndupa(s+1, e-s-1);
  68
  69                 errno = 0;
  70                 if (inet_pton(AF_INET6, n, &a->sockaddr.in6.sin6_addr) <= 0)
  71                         return errno > 0 ? -errno : -EINVAL;
  72
  73                 e++;
  74                 if (*e != ':')
  75                         return -EINVAL;
  76
  77                 e++;
  78                 r = safe_atou(e, &u);
  79                 if (r < 0)
  80                         return r;
  81
  82                 if (u <= 0 || u > 0xFFFF)
  83                         return -EINVAL;
  84
  85                 a->sockaddr.in6.sin6_family = AF_INET6;
  86                 a->sockaddr.in6.sin6_port = htons((uint16_t) u);
  87                 a->size = sizeof(struct sockaddr_in6);
  88
  89         } else if (*s == '/') {
  90                 /* AF_UNIX socket */
  91
  92                 size_t l;
  93
  94                 l = strlen(s);
  95                 if (l >= sizeof(a->sockaddr.un.sun_path))
  96                         return -EINVAL;
  97
  98                 a->sockaddr.un.sun_family = AF_UNIX;
  99                 memcpy(a->sockaddr.un.sun_path, s, l);
 100                 a->size = offsetof(struct sockaddr_un, sun_path) + l + 1;
 101
 102         } else if (*s == '@') {
 103                 /* Abstract AF_UNIX socket */
 104                 size_t l;
 105
 106                 l = strlen(s+1);
 107                 if (l >= sizeof(a->sockaddr.un.sun_path) - 1)
 108                         return -EINVAL;
 109
 110                 a->sockaddr.un.sun_family = AF_UNIX;
 111                 memcpy(a->sockaddr.un.sun_path+1, s+1, l);
 112                 a->size = offsetof(struct sockaddr_un, sun_path) + 1 + l;
 113
 114         } else {
 115                 e = strchr(s, ':');
 116                 if (e) {
 117                         r = safe_atou(e+1, &u);
 118                         if (r < 0)
 119                                 return r;
 120
 121                         if (u <= 0 || u > 0xFFFF)
 122                                 return -EINVAL;
 123
 124                         n = strndupa(s, e-s);
 125
 126                         /* IPv4 in w.x.y.z:p notation? */
 127                         r = inet_pton(AF_INET, n, &a->sockaddr.in.sin_addr);
 128                         if (r < 0)
 129                                 return -errno;
 130
 131                         if (r > 0) {
 132                                 /* Gotcha, it's a traditional IPv4 address */
 133                                 a->sockaddr.in.sin_family = AF_INET;
 134                                 a->sockaddr.in.sin_port = htons((uint16_t) u);
 135                                 a->size = sizeof(struct sockaddr_in);
 136                         } else {
 137                                 unsigned idx;
 138
 139                                 if (strlen(n) > IF_NAMESIZE-1)
 140                                         return -EINVAL;
 141
 142                                 /* Uh, our last resort, an interface name */
 143                                 idx = if_nametoindex(n);
 144                                 if (idx == 0)
 145                                         return -EINVAL;
 146
 147                                 if (!socket_ipv6_is_supported()) {
 148                                         log_warning("Binding to interface is not available since kernel does not support IPv6.");
 149                                         return -EAFNOSUPPORT;
 150                                 }
 151
 152                                 a->sockaddr.in6.sin6_family = AF_INET6;
 153                                 a->sockaddr.in6.sin6_port = htons((uint16_t) u);
 154                                 a->sockaddr.in6.sin6_scope_id = idx;
 155                                 a->sockaddr.in6.sin6_addr = in6addr_any;
 156                                 a->size = sizeof(struct sockaddr_in6);
 157                         }
 158                 } else {
 159
 160                         /* Just a port */
 161                         r = safe_atou(s, &u);
 162                         if (r < 0)
 163                                 return r;
 164
 165                         if (u <= 0 || u > 0xFFFF)
 166                                 return -EINVAL;
 167
 168                         if (socket_ipv6_is_supported()) {
 169                                 a->sockaddr.in6.sin6_family = AF_INET6;
 170                                 a->sockaddr.in6.sin6_port = htons((uint16_t) u);
 171                                 a->sockaddr.in6.sin6_addr = in6addr_any;
 172                                 a->size = sizeof(struct sockaddr_in6);
 173                         } else {
 174                                 a->sockaddr.in.sin_family = AF_INET;
 175                                 a->sockaddr.in.sin_port = htons((uint16_t) u);
 176                                 a->sockaddr.in.sin_addr.s_addr = INADDR_ANY;
 177                                 a->size = sizeof(struct sockaddr_in);
 178                         }
 179                 }
 180         }
 181
 182         return 0;
 183 }
 184
 185 int socket_address_parse_netlink(SocketAddress *a, const char *s) {
 186         int family;
 187         unsigned group = 0;
 188         _cleanup_free_ char *sfamily = NULL;
 189         assert(a);
 190         assert(s);
 191
 192         zero(*a);
 193         a->type = SOCK_RAW;
 194
 195         errno = 0;
 196         if (sscanf(s, "%ms %u", &sfamily, &group) < 1)
 197                 return errno > 0 ? -errno : -EINVAL;
 198
 199         family = netlink_family_from_string(sfamily);
 200         if (family < 0)
 201                 return -EINVAL;
 202
 203         a->sockaddr.nl.nl_family = AF_NETLINK;
 204         a->sockaddr.nl.nl_groups = group;
 205
 206         a->type = SOCK_RAW;
 207         a->size = sizeof(struct sockaddr_nl);
 208         a->protocol = family;
 209
 210         return 0;
 211 }
 212
 213 int socket_address_verify(const SocketAddress *a) {
 214         assert(a);
 215
 216         switch (socket_address_family(a)) {
 217
 218         case AF_INET:
 219                 if (a->size != sizeof(struct sockaddr_in))
 220                         return -EINVAL;
 221
 222                 if (a->sockaddr.in.sin_port == 0)
 223                         return -EINVAL;
 224
 225                 if (a->type != SOCK_STREAM && a->type != SOCK_DGRAM)
 226                         return -EINVAL;
 227
 228                 return 0;
 229
 230         case AF_INET6:
 231                 if (a->size != sizeof(struct sockaddr_in6))
 232                         return -EINVAL;
 233
 234                 if (a->sockaddr.in6.sin6_port == 0)
 235                         return -EINVAL;
 236
 237                 if (a->type != SOCK_STREAM && a->type != SOCK_DGRAM)
 238                         return -EINVAL;
 239
 240                 return 0;
 241
 242         case AF_UNIX:
 243                 if (a->size < offsetof(struct sockaddr_un, sun_path))
 244                         return -EINVAL;
 245
 246                 if (a->size > offsetof(struct sockaddr_un, sun_path)) {
 247
 248                         if (a->sockaddr.un.sun_path[0] != 0) {
 249                                 char *e;
 250
 251                                 /* path */
 252                                 e = memchr(a->sockaddr.un.sun_path, 0, sizeof(a->sockaddr.un.sun_path));
 253                                 if (!e)
 254                                         return -EINVAL;
 255
 256                                 if (a->size != offsetof(struct sockaddr_un, sun_path) + (e - a->sockaddr.un.sun_path) + 1)
 257                                         return -EINVAL;
 258                         }
 259                 }
 260
 261                 if (a->type != SOCK_STREAM && a->type != SOCK_DGRAM && a->type != SOCK_SEQPACKET)
 262                         return -EINVAL;
 263
 264                 return 0;
 265
 266         case AF_NETLINK:
 267
 268                 if (a->size != sizeof(struct sockaddr_nl))
 269                         return -EINVAL;
 270
 271                 if (a->type != SOCK_RAW && a->type != SOCK_DGRAM)
 272                         return -EINVAL;
 273
 274                 return 0;
 275
 276         default:
 277                 return -EAFNOSUPPORT;
 278         }
 279 }
 280
 281 int socket_address_print(const SocketAddress *a, char **ret) {
 282         int r;
 283
 284         assert(a);
 285         assert(ret);
 286
 287         r = socket_address_verify(a);
 288         if (r < 0)
 289                 return r;
 290
 291         if (socket_address_family(a) == AF_NETLINK) {
 292                 _cleanup_free_ char *sfamily = NULL;
 293
 294                 r = netlink_family_to_string_alloc(a->protocol, &sfamily);
 295                 if (r < 0)
 296                         return r;
 297
 298                 r = asprintf(ret, "%s %u", sfamily, a->sockaddr.nl.nl_groups);
 299                 if (r < 0)
 300                         return -ENOMEM;
 301
 302                 return 0;
 303         }
 304
 305         return sockaddr_pretty(&a->sockaddr.sa, a->size, false, ret);
 306 }
 307
 308 bool socket_address_can_accept(const SocketAddress *a) {
 309         assert(a);
 310
 311         return
 312                 a->type == SOCK_STREAM ||
 313                 a->type == SOCK_SEQPACKET;
 314 }
 315
 316 bool socket_address_equal(const SocketAddress *a, const SocketAddress *b) {
 317         assert(a);
 318         assert(b);
 319
 320         /* Invalid addresses are unequal to all */
 321         if (socket_address_verify(a) < 0 ||
 322             socket_address_verify(b) < 0)
 323                 return false;
 324
 325         if (a->type != b->type)
 326                 return false;
 327
 328         if (a->size != b->size)
 329                 return false;
 330
 331         if (socket_address_family(a) != socket_address_family(b))
 332                 return false;
 333
 334         switch (socket_address_family(a)) {
 335
 336         case AF_INET:
 337                 if (a->sockaddr.in.sin_addr.s_addr != b->sockaddr.in.sin_addr.s_addr)
 338                         return false;
 339
 340                 if (a->sockaddr.in.sin_port != b->sockaddr.in.sin_port)
 341                         return false;
 342
 343                 break;
 344
 345         case AF_INET6:
 346                 if (memcmp(&a->sockaddr.in6.sin6_addr, &b->sockaddr.in6.sin6_addr, sizeof(a->sockaddr.in6.sin6_addr)) != 0)
 347                         return false;
 348
 349                 if (a->sockaddr.in6.sin6_port != b->sockaddr.in6.sin6_port)
 350                         return false;
 351
 352                 break;
 353
 354         case AF_UNIX:
 355
 356                 if ((a->sockaddr.un.sun_path[0] == 0) != (b->sockaddr.un.sun_path[0] == 0))
 357                         return false;
 358
 359                 if (a->sockaddr.un.sun_path[0]) {
 360                         if (!strneq(a->sockaddr.un.sun_path, b->sockaddr.un.sun_path, sizeof(a->sockaddr.un.sun_path)))
 361                                 return false;
 362                 } else {
 363                         if (memcmp(a->sockaddr.un.sun_path, b->sockaddr.un.sun_path, a->size) != 0)
 364                                 return false;
 365                 }
 366
 367                 break;
 368
 369         case AF_NETLINK:
 370
 371                 if (a->protocol != b->protocol)
 372                         return false;
 373
 374                 if (a->sockaddr.nl.nl_groups != b->sockaddr.nl.nl_groups)
 375                         return false;
 376
 377                 break;
 378
 379         default:
 380                 /* Cannot compare, so we assume the addresses are different */
 381                 return false;
 382         }
 383
 384         return true;
 385 }
 386
 387 bool socket_address_is(const SocketAddress *a, const char *s, int type) {
 388         struct SocketAddress b;
 389
 390         assert(a);
 391         assert(s);
 392
 393         if (socket_address_parse(&b, s) < 0)
 394                 return false;
 395
 396         b.type = type;
 397
 398         return socket_address_equal(a, &b);
 399 }
 400
 401 bool socket_address_is_netlink(const SocketAddress *a, const char *s) {
 402         struct SocketAddress b;
 403
 404         assert(a);
 405         assert(s);
 406
 407         if (socket_address_parse_netlink(&b, s) < 0)
 408                 return false;
 409
 410         return socket_address_equal(a, &b);
 411 }
 412
 413 const char* socket_address_get_path(const SocketAddress *a) {
 414         assert(a);
 415
 416         if (socket_address_family(a) != AF_UNIX)
 417                 return NULL;
 418
 419         if (a->sockaddr.un.sun_path[0] == 0)
 420                 return NULL;
 421
 422         return a->sockaddr.un.sun_path;
 423 }
 424
 425 bool socket_ipv6_is_supported(void) {
 426         _cleanup_free_ char *l = NULL;
 427
 428         if (access("/sys/module/ipv6", F_OK) != 0)
 429                 return false;
 430
 431         /* If we can't check "disable" parameter, assume enabled */
 432         if (read_one_line_file("/sys/module/ipv6/parameters/disable", &l) < 0)
 433                 return true;
 434
 435         /* If module was loaded with disable=1 no IPv6 available */
 436         return l[0] == '0';
 437 }
 438
 439 bool socket_address_matches_fd(const SocketAddress *a, int fd) {
 440         union sockaddr_union sa;
 441         socklen_t salen = sizeof(sa), solen;
 442         int protocol, type;
 443
 444         assert(a);
 445         assert(fd >= 0);
 446
 447         if (getsockname(fd, &sa.sa, &salen) < 0)
 448                 return false;
 449
 450         if (sa.sa.sa_family != a->sockaddr.sa.sa_family)
 451                 return false;
 452
 453         solen = sizeof(type);
 454         if (getsockopt(fd, SOL_SOCKET, SO_TYPE, &type, &solen) < 0)
 455                 return false;
 456
 457         if (type != a->type)
 458                 return false;
 459
 460         if (a->protocol != 0)  {
 461                 solen = sizeof(protocol);
 462                 if (getsockopt(fd, SOL_SOCKET, SO_PROTOCOL, &protocol, &solen) < 0)
 463                         return false;
 464
 465                 if (protocol != a->protocol)
 466                         return false;
 467         }
 468
 469         switch (sa.sa.sa_family) {
 470
 471         case AF_INET:
 472                 return sa.in.sin_port == a->sockaddr.in.sin_port &&
 473                         sa.in.sin_addr.s_addr == a->sockaddr.in.sin_addr.s_addr;
 474
 475         case AF_INET6:
 476                 return sa.in6.sin6_port == a->sockaddr.in6.sin6_port &&
 477                         memcmp(&sa.in6.sin6_addr, &a->sockaddr.in6.sin6_addr, sizeof(struct in6_addr)) == 0;
 478
 479         case AF_UNIX:
 480                 return salen == a->size &&
 481                         memcmp(sa.un.sun_path, a->sockaddr.un.sun_path, salen - offsetof(struct sockaddr_un, sun_path)) == 0;
 482
 483         }
 484
 485         return false;
 486 }
 487
 488 int sockaddr_pretty(const struct sockaddr *_sa, socklen_t salen, bool translate_ipv6, char **ret) {
 489         union sockaddr_union *sa = (union sockaddr_union*) _sa;
 490         char *p;
 491
 492         assert(sa);
 493         assert(salen >= sizeof(sa->sa.sa_family));
 494
 495         switch (sa->sa.sa_family) {
 496
 497         case AF_INET: {
 498                 uint32_t a;
 499
 500                 a = ntohl(sa->in.sin_addr.s_addr);
 501
 502                 if (asprintf(&p,
 503                              "%u.%u.%u.%u:%u",
 504                              a >> 24, (a >> 16) & 0xFF, (a >> 8) & 0xFF, a & 0xFF,
 505                              ntohs(sa->in.sin_port)) < 0)
 506                         return -ENOMEM;
 507
 508                 break;
 509         }
 510
 511         case AF_INET6: {
 512                 static const unsigned char ipv4_prefix[] = {
 513                         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF
 514                 };
 515
 516                 if (translate_ipv6 && memcmp(&sa->in6.sin6_addr, ipv4_prefix, sizeof(ipv4_prefix)) == 0) {
 517                         const uint8_t *a = sa->in6.sin6_addr.s6_addr+12;
 518
 519                         if (asprintf(&p,
 520                                      "%u.%u.%u.%u:%u",
 521                                      a[0], a[1], a[2], a[3],
 522                                      ntohs(sa->in6.sin6_port)) < 0)
 523                                 return -ENOMEM;
 524                 } else {
 525                         char a[INET6_ADDRSTRLEN];
 526
 527                         if (asprintf(&p,
 528                                      "[%s]:%u",
 529                                      inet_ntop(AF_INET6, &sa->in6.sin6_addr, a, sizeof(a)),
 530                                      ntohs(sa->in6.sin6_port)) < 0)
 531                                 return -ENOMEM;
 532                 }
 533
 534                 break;
 535         }
 536
 537         case AF_UNIX:
 538                 if (salen <= offsetof(struct sockaddr_un, sun_path)) {
 539                         p = strdup("<unnamed>");
 540                         if (!p)
 541                                 return -ENOMEM;
 542
 543                 } else if (sa->un.sun_path[0] == 0) {
 544                         /* abstract */
 545
 546                         /* FIXME: We assume we can print the
 547                          * socket path here and that it hasn't
 548                          * more than one NUL byte. That is
 549                          * actually an invalid assumption */
 550
 551                         p = new(char, sizeof(sa->un.sun_path)+1);
 552                         if (!p)
 553                                 return -ENOMEM;
 554
 555                         p[0] = '@';
 556                         memcpy(p+1, sa->un.sun_path+1, sizeof(sa->un.sun_path)-1);
 557                         p[sizeof(sa->un.sun_path)] = 0;
 558
 559                 } else {
 560                         p = strndup(sa->un.sun_path, sizeof(sa->un.sun_path));
 561                         if (!ret)
 562                                 return -ENOMEM;
 563                 }
 564
 565                 break;
 566
 567         default:
 568                 return -ENOTSUP;
 569         }
 570
 571
 572         *ret = p;
 573         return 0;
 574 }
 575
 576 int getpeername_pretty(int fd, char **ret) {
 577         union sockaddr_union sa;
 578         socklen_t salen = sizeof(sa);
 579         int r;
 580
 581         assert(fd >= 0);
 582         assert(ret);
 583
 584         if (getpeername(fd, &sa.sa, &salen) < 0)
 585                 return -errno;
 586
 587         if (sa.sa.sa_family == AF_UNIX) {
 588                 struct ucred ucred = {};
 589
 590                 /* UNIX connection sockets are anonymous, so let's use
 591                  * PID/UID as pretty credentials instead */
 592
 593                 r = getpeercred(fd, &ucred);
 594                 if (r < 0)
 595                         return r;
 596
 597                 if (asprintf(ret, "PID "PID_FMT"/UID "UID_FMT, ucred.pid, ucred.uid) < 0)
 598                         return -ENOMEM;
 599
 600                 return 0;
 601         }
 602
 603         /* For remote sockets we translate IPv6 addresses back to IPv4
 604          * if applicable, since that's nicer. */
 605
 606         return sockaddr_pretty(&sa.sa, salen, true, ret);
 607 }
 608
 609 int getsockname_pretty(int fd, char **ret) {
 610         union sockaddr_union sa;
 611         socklen_t salen = sizeof(sa);
 612
 613         assert(fd >= 0);
 614         assert(ret);
 615
 616         if (getsockname(fd, &sa.sa, &salen) < 0)
 617                 return -errno;
 618
 619         /* For local sockets we do not translate IPv6 addresses back
 620          * to IPv6 if applicable, since this is usually used for
 621          * listening sockets where the difference between IPv4 and
 622          * IPv6 matters. */
 623
 624         return sockaddr_pretty(&sa.sa, salen, false, ret);
 625 }
 626
 627 int socknameinfo_pretty(union sockaddr_union *sa, socklen_t salen, char **_ret) {
 628         int r;
 629         char host[NI_MAXHOST], *ret;
 630
 631         assert(_ret);
 632
 633         r = getnameinfo(&sa->sa, salen, host, sizeof(host), NULL, 0,
 634                         NI_IDN|NI_IDN_USE_STD3_ASCII_RULES);
 635         if (r != 0) {
 636                 int saved_errno = errno;
 637
 638                 r = sockaddr_pretty(&sa->sa, salen, true, &ret);
 639                 if (r < 0) {
 640                         log_error_errno(-r, "sockadd_pretty() failed: %m");
 641                         return r;
 642                 }
 643
 644                 log_debug("getnameinfo(%s) failed: %s", ret, strerror(saved_errno));
 645         } else {
 646                 ret = strdup(host);
 647                 if (!ret)
 648                         return log_oom();
 649         }
 650
 651         *_ret = ret;
 652         return 0;
 653 }
 654
 655 int getnameinfo_pretty(int fd, char **ret) {
 656         union sockaddr_union sa;
 657         socklen_t salen = sizeof(sa);
 658
 659         assert(fd >= 0);
 660         assert(ret);
 661
 662         if (getsockname(fd, &sa.sa, &salen) < 0) {
 663                 log_error("getsockname(%d) failed: %m", fd);
 664                 return -errno;
 665         }
 666
 667         return socknameinfo_pretty(&sa, salen, ret);
 668 }
 669
 670 int socket_address_unlink(SocketAddress *a) {
 671         assert(a);
 672
 673         if (socket_address_family(a) != AF_UNIX)
 674                 return 0;
 675
 676         if (a->sockaddr.un.sun_path[0] == 0)
 677                 return 0;
 678
 679         if (unlink(a->sockaddr.un.sun_path) < 0)
 680                 return -errno;
 681
 682         return 1;
 683 }
 684
 685 static const char* const netlink_family_table[] = {
 686         [NETLINK_ROUTE] = "route",
 687         [NETLINK_FIREWALL] = "firewall",
 688         [NETLINK_INET_DIAG] = "inet-diag",
 689         [NETLINK_NFLOG] = "nflog",
 690         [NETLINK_XFRM] = "xfrm",
 691         [NETLINK_SELINUX] = "selinux",
 692         [NETLINK_ISCSI] = "iscsi",
 693         [NETLINK_AUDIT] = "audit",
 694         [NETLINK_FIB_LOOKUP] = "fib-lookup",
 695         [NETLINK_CONNECTOR] = "connector",
 696         [NETLINK_NETFILTER] = "netfilter",
 697         [NETLINK_IP6_FW] = "ip6-fw",
 698         [NETLINK_DNRTMSG] = "dnrtmsg",
 699         [NETLINK_KOBJECT_UEVENT] = "kobject-uevent",
 700         [NETLINK_GENERIC] = "generic",
 701         [NETLINK_SCSITRANSPORT] = "scsitransport",
 702         [NETLINK_ECRYPTFS] = "ecryptfs"
 703 };
 704
 705 DEFINE_STRING_TABLE_LOOKUP_WITH_FALLBACK(netlink_family, int, INT_MAX);
 706
 707 static const char* const socket_address_bind_ipv6_only_table[_SOCKET_ADDRESS_BIND_IPV6_ONLY_MAX] = {
 708         [SOCKET_ADDRESS_DEFAULT] = "default",
 709         [SOCKET_ADDRESS_BOTH] = "both",
 710         [SOCKET_ADDRESS_IPV6_ONLY] = "ipv6-only"
 711 };
 712
 713 DEFINE_STRING_TABLE_LOOKUP(socket_address_bind_ipv6_only, SocketAddressBindIPv6Only);
 714
 715 bool sockaddr_equal(const union sockaddr_union *a, const union sockaddr_union *b) {
 716         assert(a);
 717         assert(b);
 718
 719         if (a->sa.sa_family != b->sa.sa_family)
 720                 return false;
 721
 722         if (a->sa.sa_family == AF_INET)
 723                 return a->in.sin_addr.s_addr == b->in.sin_addr.s_addr;
 724
 725         if (a->sa.sa_family == AF_INET6)
 726                 return memcmp(&a->in6.sin6_addr, &b->in6.sin6_addr, sizeof(a->in6.sin6_addr)) == 0;
 727
 728         return false;
 729 }
 730
 731 char* ether_addr_to_string(const struct ether_addr *addr, char buffer[ETHER_ADDR_TO_STRING_MAX]) {
 732         assert(addr);
 733         assert(buffer);
 734
 735         /* Like ether_ntoa() but uses %02x instead of %x to print
 736          * ethernet addresses, which makes them look less funny. Also,
 737          * doesn't use a static buffer. */
 738
 739         sprintf(buffer, "%02x:%02x:%02x:%02x:%02x:%02x",
 740                 addr->ether_addr_octet[0],
 741                 addr->ether_addr_octet[1],
 742                 addr->ether_addr_octet[2],
 743                 addr->ether_addr_octet[3],
 744                 addr->ether_addr_octet[4],
 745                 addr->ether_addr_octet[5]);
 746
 747         return buffer;
 748 }