contrib/bind9/lib/isc/unix/net.c

   1 /*
   2  * Copyright (C) 2004, 2005, 2007, 2008, 2012, 2014, 2015  Internet Systems Consortium, Inc. ("ISC")
   3  * Copyright (C) 1999-2003  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 /* $Id$ */
  19
  20 #include <config.h>
  21
  22 #include <sys/types.h>
  23
  24 #if defined(HAVE_SYS_SYSCTL_H)
  25 #if defined(HAVE_SYS_PARAM_H)
  26 #include <sys/param.h>
  27 #endif
  28 #include <sys/sysctl.h>
  29 #endif
  30
  31 #include <errno.h>
  32 #include <unistd.h>
  33
  34 #include <isc/log.h>
  35 #include <isc/msgs.h>
  36 #include <isc/net.h>
  37 #include <isc/once.h>
  38 #include <isc/strerror.h>
  39 #include <isc/string.h>
  40 #include <isc/util.h>
  41
  42 /*%
  43  * Definitions about UDP port range specification.  This is a total mess of
  44  * portability variants: some use sysctl (but the sysctl names vary), some use
  45  * system-specific interfaces, some have the same interface for IPv4 and IPv6,
  46  * some separate them, etc...
  47  */
  48
  49 /*%
  50  * The last resort defaults: use all non well known port space
  51  */
  52 #ifndef ISC_NET_PORTRANGELOW
  53 #define ISC_NET_PORTRANGELOW 1024
  54 #endif  /* ISC_NET_PORTRANGELOW */
  55 #ifndef ISC_NET_PORTRANGEHIGH
  56 #define ISC_NET_PORTRANGEHIGH 65535
  57 #endif  /* ISC_NET_PORTRANGEHIGH */
  58
  59 #ifdef HAVE_SYSCTLBYNAME
  60
  61 /*%
  62  * sysctl variants
  63  */
  64 #if defined(__FreeBSD__) || defined(__APPLE__) || defined(__DragonFly__)
  65 #define USE_SYSCTL_PORTRANGE
  66 #define SYSCTL_V4PORTRANGE_LOW  "net.inet.ip.portrange.hifirst"
  67 #define SYSCTL_V4PORTRANGE_HIGH "net.inet.ip.portrange.hilast"
  68 #define SYSCTL_V6PORTRANGE_LOW  "net.inet.ip.portrange.hifirst"
  69 #define SYSCTL_V6PORTRANGE_HIGH "net.inet.ip.portrange.hilast"
  70 #endif
  71
  72 #ifdef __NetBSD__
  73 #define USE_SYSCTL_PORTRANGE
  74 #define SYSCTL_V4PORTRANGE_LOW  "net.inet.ip.anonportmin"
  75 #define SYSCTL_V4PORTRANGE_HIGH "net.inet.ip.anonportmax"
  76 #define SYSCTL_V6PORTRANGE_LOW  "net.inet6.ip6.anonportmin"
  77 #define SYSCTL_V6PORTRANGE_HIGH "net.inet6.ip6.anonportmax"
  78 #endif
  79
  80 #else /* !HAVE_SYSCTLBYNAME */
  81
  82 #ifdef __OpenBSD__
  83 #define USE_SYSCTL_PORTRANGE
  84 #define SYSCTL_V4PORTRANGE_LOW  { CTL_NET, PF_INET, IPPROTO_IP, \
  85                                   IPCTL_IPPORT_HIFIRSTAUTO }
  86 #define SYSCTL_V4PORTRANGE_HIGH { CTL_NET, PF_INET, IPPROTO_IP, \
  87                                   IPCTL_IPPORT_HILASTAUTO }
  88 /* Same for IPv6 */
  89 #define SYSCTL_V6PORTRANGE_LOW  SYSCTL_V4PORTRANGE_LOW
  90 #define SYSCTL_V6PORTRANGE_HIGH SYSCTL_V4PORTRANGE_HIGH
  91 #endif
  92
  93 #endif /* HAVE_SYSCTLBYNAME */
  94
  95 #if defined(ISC_PLATFORM_HAVEIPV6)
  96 # if defined(ISC_PLATFORM_NEEDIN6ADDRANY)
  97 const struct in6_addr isc_net_in6addrany = IN6ADDR_ANY_INIT;
  98 # endif
  99
 100 # if defined(ISC_PLATFORM_NEEDIN6ADDRLOOPBACK)
 101 const struct in6_addr isc_net_in6addrloop = IN6ADDR_LOOPBACK_INIT;
 102 # endif
 103
 104 # if defined(WANT_IPV6)
 105 static isc_once_t       once_ipv6only = ISC_ONCE_INIT;
 106 # endif
 107
 108 # if defined(ISC_PLATFORM_HAVEIN6PKTINFO)
 109 static isc_once_t       once_ipv6pktinfo = ISC_ONCE_INIT;
 110 # endif
 111 #endif /* ISC_PLATFORM_HAVEIPV6 */
 112
 113 static isc_once_t       once = ISC_ONCE_INIT;
 114
 115 static isc_result_t     ipv4_result = ISC_R_NOTFOUND;
 116 static isc_result_t     ipv6_result = ISC_R_NOTFOUND;
 117 static isc_result_t     unix_result = ISC_R_NOTFOUND;
 118 static isc_result_t     ipv6only_result = ISC_R_NOTFOUND;
 119 static isc_result_t     ipv6pktinfo_result = ISC_R_NOTFOUND;
 120
 121 static isc_result_t
 122 try_proto(int domain) {
 123         int s;
 124         isc_result_t result = ISC_R_SUCCESS;
 125         char strbuf[ISC_STRERRORSIZE];
 126
 127         s = socket(domain, SOCK_STREAM, 0);
 128         if (s == -1) {
 129                 switch (errno) {
 130 #ifdef EAFNOSUPPORT
 131                 case EAFNOSUPPORT:
 132 #endif
 133 #ifdef EPROTONOSUPPORT
 134                 case EPROTONOSUPPORT:
 135 #endif
 136 #ifdef EINVAL
 137                 case EINVAL:
 138 #endif
 139                         return (ISC_R_NOTFOUND);
 140                 default:
 141                         isc__strerror(errno, strbuf, sizeof(strbuf));
 142                         UNEXPECTED_ERROR(__FILE__, __LINE__,
 143                                          "socket() %s: %s",
 144                                          isc_msgcat_get(isc_msgcat,
 145                                                         ISC_MSGSET_GENERAL,
 146                                                         ISC_MSG_FAILED,
 147                                                         "failed"),
 148                                          strbuf);
 149                         return (ISC_R_UNEXPECTED);
 150                 }
 151         }
 152
 153 #ifdef ISC_PLATFORM_HAVEIPV6
 154 #ifdef WANT_IPV6
 155 #ifdef ISC_PLATFORM_HAVEIN6PKTINFO
 156         if (domain == PF_INET6) {
 157                 struct sockaddr_in6 sin6;
 158                 unsigned int len;
 159
 160                 /*
 161                  * Check to see if IPv6 is broken, as is common on Linux.
 162                  */
 163                 len = sizeof(sin6);
 164                 if (getsockname(s, (struct sockaddr *)&sin6, (void *)&len) < 0)
 165                 {
 166                         isc_log_write(isc_lctx, ISC_LOGCATEGORY_GENERAL,
 167                                       ISC_LOGMODULE_SOCKET, ISC_LOG_ERROR,
 168                                       "retrieving the address of an IPv6 "
 169                                       "socket from the kernel failed.");
 170                         isc_log_write(isc_lctx, ISC_LOGCATEGORY_GENERAL,
 171                                       ISC_LOGMODULE_SOCKET, ISC_LOG_ERROR,
 172                                       "IPv6 is not supported.");
 173                         result = ISC_R_NOTFOUND;
 174                 } else {
 175                         if (len == sizeof(struct sockaddr_in6))
 176                                 result = ISC_R_SUCCESS;
 177                         else {
 178                                 isc_log_write(isc_lctx,
 179                                               ISC_LOGCATEGORY_GENERAL,
 180                                               ISC_LOGMODULE_SOCKET,
 181                                               ISC_LOG_ERROR,
 182                                               "IPv6 structures in kernel and "
 183                                               "user space do not match.");
 184                                 isc_log_write(isc_lctx,
 185                                               ISC_LOGCATEGORY_GENERAL,
 186                                               ISC_LOGMODULE_SOCKET,
 187                                               ISC_LOG_ERROR,
 188                                               "IPv6 is not supported.");
 189                                 result = ISC_R_NOTFOUND;
 190                         }
 191                 }
 192         }
 193 #endif
 194 #endif
 195 #endif
 196
 197         (void)close(s);
 198
 199         return (result);
 200 }
 201
 202 static void
 203 initialize_action(void) {
 204         ipv4_result = try_proto(PF_INET);
 205 #ifdef ISC_PLATFORM_HAVEIPV6
 206 #ifdef WANT_IPV6
 207 #ifdef ISC_PLATFORM_HAVEIN6PKTINFO
 208         ipv6_result = try_proto(PF_INET6);
 209 #endif
 210 #endif
 211 #endif
 212 #ifdef ISC_PLATFORM_HAVESYSUNH
 213         unix_result = try_proto(PF_UNIX);
 214 #endif
 215 }
 216
 217 static void
 218 initialize(void) {
 219         RUNTIME_CHECK(isc_once_do(&once, initialize_action) == ISC_R_SUCCESS);
 220 }
 221
 222 isc_result_t
 223 isc_net_probeipv4(void) {
 224         initialize();
 225         return (ipv4_result);
 226 }
 227
 228 isc_result_t
 229 isc_net_probeipv6(void) {
 230         initialize();
 231         return (ipv6_result);
 232 }
 233
 234 isc_result_t
 235 isc_net_probeunix(void) {
 236         initialize();
 237         return (unix_result);
 238 }
 239
 240 #ifdef ISC_PLATFORM_HAVEIPV6
 241 #ifdef WANT_IPV6
 242 static void
 243 try_ipv6only(void) {
 244 #ifdef IPV6_V6ONLY
 245         int s, on;
 246         char strbuf[ISC_STRERRORSIZE];
 247 #endif
 248         isc_result_t result;
 249
 250         result = isc_net_probeipv6();
 251         if (result != ISC_R_SUCCESS) {
 252                 ipv6only_result = result;
 253                 return;
 254         }
 255
 256 #ifndef IPV6_V6ONLY
 257         ipv6only_result = ISC_R_NOTFOUND;
 258         return;
 259 #else
 260         /* check for TCP sockets */
 261         s = socket(PF_INET6, SOCK_STREAM, 0);
 262         if (s == -1) {
 263                 isc__strerror(errno, strbuf, sizeof(strbuf));
 264                 UNEXPECTED_ERROR(__FILE__, __LINE__,
 265                                  "socket() %s: %s",
 266                                  isc_msgcat_get(isc_msgcat,
 267                                                 ISC_MSGSET_GENERAL,
 268                                                 ISC_MSG_FAILED,
 269                                                 "failed"),
 270                                  strbuf);
 271                 ipv6only_result = ISC_R_UNEXPECTED;
 272                 return;
 273         }
 274
 275         on = 1;
 276         if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) < 0) {
 277                 ipv6only_result = ISC_R_NOTFOUND;
 278                 goto close;
 279         }
 280
 281         close(s);
 282
 283         /* check for UDP sockets */
 284         s = socket(PF_INET6, SOCK_DGRAM, 0);
 285         if (s == -1) {
 286                 isc__strerror(errno, strbuf, sizeof(strbuf));
 287                 UNEXPECTED_ERROR(__FILE__, __LINE__,
 288                                  "socket() %s: %s",
 289                                  isc_msgcat_get(isc_msgcat,
 290                                                 ISC_MSGSET_GENERAL,
 291                                                 ISC_MSG_FAILED,
 292                                                 "failed"),
 293                                  strbuf);
 294                 ipv6only_result = ISC_R_UNEXPECTED;
 295                 return;
 296         }
 297
 298         on = 1;
 299         if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) < 0) {
 300                 ipv6only_result = ISC_R_NOTFOUND;
 301                 goto close;
 302         }
 303
 304         ipv6only_result = ISC_R_SUCCESS;
 305
 306 close:
 307         close(s);
 308         return;
 309 #endif /* IPV6_V6ONLY */
 310 }
 311
 312 static void
 313 initialize_ipv6only(void) {
 314         RUNTIME_CHECK(isc_once_do(&once_ipv6only,
 315                                   try_ipv6only) == ISC_R_SUCCESS);
 316 }
 317 #endif /* WANT_IPV6 */
 318
 319 #ifdef ISC_PLATFORM_HAVEIN6PKTINFO
 320 #ifdef WANT_IPV6
 321 static void
 322 try_ipv6pktinfo(void) {
 323         int s, on;
 324         char strbuf[ISC_STRERRORSIZE];
 325         isc_result_t result;
 326         int optname;
 327
 328         result = isc_net_probeipv6();
 329         if (result != ISC_R_SUCCESS) {
 330                 ipv6pktinfo_result = result;
 331                 return;
 332         }
 333
 334         /* we only use this for UDP sockets */
 335         s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_UDP);
 336         if (s == -1) {
 337                 isc__strerror(errno, strbuf, sizeof(strbuf));
 338                 UNEXPECTED_ERROR(__FILE__, __LINE__,
 339                                  "socket() %s: %s",
 340                                  isc_msgcat_get(isc_msgcat,
 341                                                 ISC_MSGSET_GENERAL,
 342                                                 ISC_MSG_FAILED,
 343                                                 "failed"),
 344                                  strbuf);
 345                 ipv6pktinfo_result = ISC_R_UNEXPECTED;
 346                 return;
 347         }
 348
 349 #ifdef IPV6_RECVPKTINFO
 350         optname = IPV6_RECVPKTINFO;
 351 #else
 352         optname = IPV6_PKTINFO;
 353 #endif
 354         on = 1;
 355         if (setsockopt(s, IPPROTO_IPV6, optname, &on, sizeof(on)) < 0) {
 356                 ipv6pktinfo_result = ISC_R_NOTFOUND;
 357                 goto close;
 358         }
 359
 360         ipv6pktinfo_result = ISC_R_SUCCESS;
 361
 362 close:
 363         close(s);
 364         return;
 365 }
 366
 367 static void
 368 initialize_ipv6pktinfo(void) {
 369         RUNTIME_CHECK(isc_once_do(&once_ipv6pktinfo,
 370                                   try_ipv6pktinfo) == ISC_R_SUCCESS);
 371 }
 372 #endif /* WANT_IPV6 */
 373 #endif /* ISC_PLATFORM_HAVEIN6PKTINFO */
 374 #endif /* ISC_PLATFORM_HAVEIPV6 */
 375
 376 isc_result_t
 377 isc_net_probe_ipv6only(void) {
 378 #ifdef ISC_PLATFORM_HAVEIPV6
 379 #ifdef WANT_IPV6
 380         initialize_ipv6only();
 381 #else
 382         ipv6only_result = ISC_R_NOTFOUND;
 383 #endif
 384 #endif
 385         return (ipv6only_result);
 386 }
 387
 388 isc_result_t
 389 isc_net_probe_ipv6pktinfo(void) {
 390 #ifdef ISC_PLATFORM_HAVEIPV6
 391 #ifdef ISC_PLATFORM_HAVEIN6PKTINFO
 392 #ifdef WANT_IPV6
 393         initialize_ipv6pktinfo();
 394 #else
 395         ipv6pktinfo_result = ISC_R_NOTFOUND;
 396 #endif
 397 #endif
 398 #endif
 399         return (ipv6pktinfo_result);
 400 }
 401
 402 #if defined(USE_SYSCTL_PORTRANGE)
 403 #if defined(HAVE_SYSCTLBYNAME)
 404 static isc_result_t
 405 getudpportrange_sysctl(int af, in_port_t *low, in_port_t *high) {
 406         int port_low, port_high;
 407         size_t portlen;
 408         const char *sysctlname_lowport, *sysctlname_hiport;
 409
 410         if (af == AF_INET) {
 411                 sysctlname_lowport = SYSCTL_V4PORTRANGE_LOW;
 412                 sysctlname_hiport = SYSCTL_V4PORTRANGE_HIGH;
 413         } else {
 414                 sysctlname_lowport = SYSCTL_V6PORTRANGE_LOW;
 415                 sysctlname_hiport = SYSCTL_V6PORTRANGE_HIGH;
 416         }
 417         portlen = sizeof(port_low);
 418         if (sysctlbyname(sysctlname_lowport, &port_low, &portlen,
 419                          NULL, 0) < 0) {
 420                 return (ISC_R_FAILURE);
 421         }
 422         portlen = sizeof(port_high);
 423         if (sysctlbyname(sysctlname_hiport, &port_high, &portlen,
 424                          NULL, 0) < 0) {
 425                 return (ISC_R_FAILURE);
 426         }
 427         if ((port_low & ~0xffff) != 0 || (port_high & ~0xffff) != 0)
 428                 return (ISC_R_RANGE);
 429
 430         *low = (in_port_t)port_low;
 431         *high = (in_port_t)port_high;
 432
 433         return (ISC_R_SUCCESS);
 434 }
 435 #else /* !HAVE_SYSCTLBYNAME */
 436 static isc_result_t
 437 getudpportrange_sysctl(int af, in_port_t *low, in_port_t *high) {
 438         int mib_lo4[4] = SYSCTL_V4PORTRANGE_LOW;
 439         int mib_hi4[4] = SYSCTL_V4PORTRANGE_HIGH;
 440         int mib_lo6[4] = SYSCTL_V6PORTRANGE_LOW;
 441         int mib_hi6[4] = SYSCTL_V6PORTRANGE_HIGH;
 442         int *mib_lo, *mib_hi, miblen;
 443         int port_low, port_high;
 444         size_t portlen;
 445
 446         if (af == AF_INET) {
 447                 mib_lo = mib_lo4;
 448                 mib_hi = mib_hi4;
 449                 miblen = sizeof(mib_lo4) / sizeof(mib_lo4[0]);
 450         } else {
 451                 mib_lo = mib_lo6;
 452                 mib_hi = mib_hi6;
 453                 miblen = sizeof(mib_lo6) / sizeof(mib_lo6[0]);
 454         }
 455
 456         portlen = sizeof(port_low);
 457         if (sysctl(mib_lo, miblen, &port_low, &portlen, NULL, 0) < 0) {
 458                 return (ISC_R_FAILURE);
 459         }
 460
 461         portlen = sizeof(port_high);
 462         if (sysctl(mib_hi, miblen, &port_high, &portlen, NULL, 0) < 0) {
 463                 return (ISC_R_FAILURE);
 464         }
 465
 466         if ((port_low & ~0xffff) != 0 || (port_high & ~0xffff) != 0)
 467                 return (ISC_R_RANGE);
 468
 469         *low = (in_port_t) port_low;
 470         *high = (in_port_t) port_high;
 471
 472         return (ISC_R_SUCCESS);
 473 }
 474 #endif /* HAVE_SYSCTLBYNAME */
 475 #endif /* USE_SYSCTL_PORTRANGE */
 476
 477 isc_result_t
 478 isc_net_getudpportrange(int af, in_port_t *low, in_port_t *high) {
 479         int result = ISC_R_FAILURE;
 480 #if !defined(USE_SYSCTL_PORTRANGE) && defined(__linux)
 481         FILE *fp;
 482 #endif
 483
 484         REQUIRE(low != NULL && high != NULL);
 485
 486 #if defined(USE_SYSCTL_PORTRANGE)
 487         result = getudpportrange_sysctl(af, low, high);
 488 #elif defined(__linux)
 489
 490         UNUSED(af);
 491
 492         /*
 493          * Linux local ports are address family agnostic.
 494          */
 495         fp = fopen("/proc/sys/net/ipv4/ip_local_port_range", "r");
 496         if (fp != NULL) {
 497                 int n;
 498                 unsigned int l, h;
 499
 500                 n = fscanf(fp, "%u %u", &l, &h);
 501                 if (n == 2 && (l & ~0xffff) == 0 && (h & ~0xffff) == 0) {
 502                         *low = l;
 503                         *high = h;
 504                         result = ISC_R_SUCCESS;
 505                 }
 506                 fclose(fp);
 507         }
 508 #else
 509         UNUSED(af);
 510 #endif
 511
 512         if (result != ISC_R_SUCCESS) {
 513                 *low = ISC_NET_PORTRANGELOW;
 514                 *high = ISC_NET_PORTRANGEHIGH;
 515         }
 516
 517         return (ISC_R_SUCCESS); /* we currently never fail in this function */
 518 }
 519
 520 void
 521 isc_net_disableipv4(void) {
 522         initialize();
 523         if (ipv4_result == ISC_R_SUCCESS)
 524                 ipv4_result = ISC_R_DISABLED;
 525 }
 526
 527 void
 528 isc_net_disableipv6(void) {
 529         initialize();
 530         if (ipv6_result == ISC_R_SUCCESS)
 531                 ipv6_result = ISC_R_DISABLED;
 532 }
 533
 534 void
 535 isc_net_enableipv4(void) {
 536         initialize();
 537         if (ipv4_result == ISC_R_DISABLED)
 538                 ipv4_result = ISC_R_SUCCESS;
 539 }
 540
 541 void
 542 isc_net_enableipv6(void) {
 543         initialize();
 544         if (ipv6_result == ISC_R_DISABLED)
 545                 ipv6_result = ISC_R_SUCCESS;
 546 }