src/backend/libpq/ifaddr.c

   1 /*-------------------------------------------------------------------------
   2  *
   3  * ifaddr.c
   4  *        IP netmask calculations, and enumerating network interfaces.
   5  *
   6  * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group
   7  * Portions Copyright (c) 1994, Regents of the University of California
   8  *
   9  *
  10  * IDENTIFICATION
  11  *        src/backend/libpq/ifaddr.c
  12  *
  13  * This file and the IPV6 implementation were initially provided by
  14  * Nigel Kukard <nkukard@lbsd.net>, Linux Based Systems Design
  15  * http://www.lbsd.net.
  16  *
  17  *-------------------------------------------------------------------------
  18  */
  19
  20 #include "postgres.h"
  21
  22 #include <unistd.h>
  23 #include <sys/stat.h>
  24 #include <sys/socket.h>
  25 #include <netdb.h>
  26 #include <netinet/in.h>
  27 #ifdef HAVE_NETINET_TCP_H
  28 #include <netinet/tcp.h>
  29 #endif
  30 #include <sys/file.h>
  31
  32 #include "libpq/ifaddr.h"
  33 #include "port/pg_bswap.h"
  34
  35 static int      range_sockaddr_AF_INET(const struct sockaddr_in *addr,
  36                                                                    const struct sockaddr_in *netaddr,
  37                                                                    const struct sockaddr_in *netmask);
  38
  39 #ifdef HAVE_IPV6
  40 static int      range_sockaddr_AF_INET6(const struct sockaddr_in6 *addr,
  41                                                                         const struct sockaddr_in6 *netaddr,
  42                                                                         const struct sockaddr_in6 *netmask);
  43 #endif
  44
  45
  46 /*
  47  * pg_range_sockaddr - is addr within the subnet specified by netaddr/netmask ?
  48  *
  49  * Note: caller must already have verified that all three addresses are
  50  * in the same address family; and AF_UNIX addresses are not supported.
  51  */
  52 int
  53 pg_range_sockaddr(const struct sockaddr_storage *addr,
  54                                   const struct sockaddr_storage *netaddr,
  55                                   const struct sockaddr_storage *netmask)
  56 {
  57         if (addr->ss_family == AF_INET)
  58                 return range_sockaddr_AF_INET((const struct sockaddr_in *) addr,
  59                                                                           (const struct sockaddr_in *) netaddr,
  60                                                                           (const struct sockaddr_in *) netmask);
  61 #ifdef HAVE_IPV6
  62         else if (addr->ss_family == AF_INET6)
  63                 return range_sockaddr_AF_INET6((const struct sockaddr_in6 *) addr,
  64                                                                            (const struct sockaddr_in6 *) netaddr,
  65                                                                            (const struct sockaddr_in6 *) netmask);
  66 #endif
  67         else
  68                 return 0;
  69 }
  70
  71 static int
  72 range_sockaddr_AF_INET(const struct sockaddr_in *addr,
  73                                            const struct sockaddr_in *netaddr,
  74                                            const struct sockaddr_in *netmask)
  75 {
  76         if (((addr->sin_addr.s_addr ^ netaddr->sin_addr.s_addr) &
  77                  netmask->sin_addr.s_addr) == 0)
  78                 return 1;
  79         else
  80                 return 0;
  81 }
  82
  83
  84 #ifdef HAVE_IPV6
  85
  86 static int
  87 range_sockaddr_AF_INET6(const struct sockaddr_in6 *addr,
  88                                                 const struct sockaddr_in6 *netaddr,
  89                                                 const struct sockaddr_in6 *netmask)
  90 {
  91         int                     i;
  92
  93         for (i = 0; i < 16; i++)
  94         {
  95                 if (((addr->sin6_addr.s6_addr[i] ^ netaddr->sin6_addr.s6_addr[i]) &
  96                          netmask->sin6_addr.s6_addr[i]) != 0)
  97                         return 0;
  98         }
  99
 100         return 1;
 101 }
 102 #endif                                                  /* HAVE_IPV6 */
 103
 104 /*
 105  *      pg_sockaddr_cidr_mask - make a network mask of the appropriate family
 106  *        and required number of significant bits
 107  *
 108  * numbits can be null, in which case the mask is fully set.
 109  *
 110  * The resulting mask is placed in *mask, which had better be big enough.
 111  *
 112  * Return value is 0 if okay, -1 if not.
 113  */
 114 int
 115 pg_sockaddr_cidr_mask(struct sockaddr_storage *mask, char *numbits, int family)
 116 {
 117         long            bits;
 118         char       *endptr;
 119
 120         if (numbits == NULL)
 121         {
 122                 bits = (family == AF_INET) ? 32 : 128;
 123         }
 124         else
 125         {
 126                 bits = strtol(numbits, &endptr, 10);
 127                 if (*numbits == '\0' || *endptr != '\0')
 128                         return -1;
 129         }
 130
 131         switch (family)
 132         {
 133                 case AF_INET:
 134                         {
 135                                 struct sockaddr_in mask4;
 136                                 long            maskl;
 137
 138                                 if (bits < 0 || bits > 32)
 139                                         return -1;
 140                                 memset(&mask4, 0, sizeof(mask4));
 141                                 /* avoid "x << 32", which is not portable */
 142                                 if (bits > 0)
 143                                         maskl = (0xffffffffUL << (32 - (int) bits))
 144                                                 & 0xffffffffUL;
 145                                 else
 146                                         maskl = 0;
 147                                 mask4.sin_addr.s_addr = pg_hton32(maskl);
 148                                 memcpy(mask, &mask4, sizeof(mask4));
 149                                 break;
 150                         }
 151
 152 #ifdef HAVE_IPV6
 153                 case AF_INET6:
 154                         {
 155                                 struct sockaddr_in6 mask6;
 156                                 int                     i;
 157
 158                                 if (bits < 0 || bits > 128)
 159                                         return -1;
 160                                 memset(&mask6, 0, sizeof(mask6));
 161                                 for (i = 0; i < 16; i++)
 162                                 {
 163                                         if (bits <= 0)
 164                                                 mask6.sin6_addr.s6_addr[i] = 0;
 165                                         else if (bits >= 8)
 166                                                 mask6.sin6_addr.s6_addr[i] = 0xff;
 167                                         else
 168                                         {
 169                                                 mask6.sin6_addr.s6_addr[i] =
 170                                                         (0xff << (8 - (int) bits)) & 0xff;
 171                                         }
 172                                         bits -= 8;
 173                                 }
 174                                 memcpy(mask, &mask6, sizeof(mask6));
 175                                 break;
 176                         }
 177 #endif
 178                 default:
 179                         return -1;
 180         }
 181
 182         mask->ss_family = family;
 183         return 0;
 184 }
 185
 186
 187 /*
 188  * Run the callback function for the addr/mask, after making sure the
 189  * mask is sane for the addr.
 190  */
 191 static void
 192 run_ifaddr_callback(PgIfAddrCallback callback, void *cb_data,
 193                                         struct sockaddr *addr, struct sockaddr *mask)
 194 {
 195         struct sockaddr_storage fullmask;
 196
 197         if (!addr)
 198                 return;
 199
 200         /* Check that the mask is valid */
 201         if (mask)
 202         {
 203                 if (mask->sa_family != addr->sa_family)
 204                 {
 205                         mask = NULL;
 206                 }
 207                 else if (mask->sa_family == AF_INET)
 208                 {
 209                         if (((struct sockaddr_in *) mask)->sin_addr.s_addr == INADDR_ANY)
 210                                 mask = NULL;
 211                 }
 212 #ifdef HAVE_IPV6
 213                 else if (mask->sa_family == AF_INET6)
 214                 {
 215                         if (IN6_IS_ADDR_UNSPECIFIED(&((struct sockaddr_in6 *) mask)->sin6_addr))
 216                                 mask = NULL;
 217                 }
 218 #endif
 219         }
 220
 221         /* If mask is invalid, generate our own fully-set mask */
 222         if (!mask)
 223         {
 224                 pg_sockaddr_cidr_mask(&fullmask, NULL, addr->sa_family);
 225                 mask = (struct sockaddr *) &fullmask;
 226         }
 227
 228         (*callback) (addr, mask, cb_data);
 229 }
 230
 231 #ifdef WIN32
 232
 233 #include <winsock2.h>
 234 #include <ws2tcpip.h>
 235
 236 /*
 237  * Enumerate the system's network interface addresses and call the callback
 238  * for each one.  Returns 0 if successful, -1 if trouble.
 239  *
 240  * This version is for Win32.  Uses the Winsock 2 functions (ie: ws2_32.dll)
 241  */
 242 int
 243 pg_foreach_ifaddr(PgIfAddrCallback callback, void *cb_data)
 244 {
 245         INTERFACE_INFO *ptr,
 246                            *ii = NULL;
 247         unsigned long length,
 248                                 i;
 249         unsigned long n_ii = 0;
 250         SOCKET          sock;
 251         int                     error;
 252
 253         sock = WSASocket(AF_INET, SOCK_DGRAM, 0, 0, 0, 0);
 254         if (sock == INVALID_SOCKET)
 255                 return -1;
 256
 257         while (n_ii < 1024)
 258         {
 259                 n_ii += 64;
 260                 ptr = realloc(ii, sizeof(INTERFACE_INFO) * n_ii);
 261                 if (!ptr)
 262                 {
 263                         free(ii);
 264                         closesocket(sock);
 265                         errno = ENOMEM;
 266                         return -1;
 267                 }
 268
 269                 ii = ptr;
 270                 if (WSAIoctl(sock, SIO_GET_INTERFACE_LIST, 0, 0,
 271                                          ii, n_ii * sizeof(INTERFACE_INFO),
 272                                          &length, 0, 0) == SOCKET_ERROR)
 273                 {
 274                         error = WSAGetLastError();
 275                         if (error == WSAEFAULT || error == WSAENOBUFS)
 276                                 continue;               /* need to make the buffer bigger */
 277                         closesocket(sock);
 278                         free(ii);
 279                         return -1;
 280                 }
 281
 282                 break;
 283         }
 284
 285         for (i = 0; i < length / sizeof(INTERFACE_INFO); ++i)
 286                 run_ifaddr_callback(callback, cb_data,
 287                                                         (struct sockaddr *) &ii[i].iiAddress,
 288                                                         (struct sockaddr *) &ii[i].iiNetmask);
 289
 290         closesocket(sock);
 291         free(ii);
 292         return 0;
 293 }
 294 #elif HAVE_GETIFADDRS                   /* && !WIN32 */
 295
 296 #ifdef HAVE_IFADDRS_H
 297 #include <ifaddrs.h>
 298 #endif
 299
 300 /*
 301  * Enumerate the system's network interface addresses and call the callback
 302  * for each one.  Returns 0 if successful, -1 if trouble.
 303  *
 304  * This version uses the getifaddrs() interface, which is available on
 305  * BSDs, AIX, and modern Linux.
 306  */
 307 int
 308 pg_foreach_ifaddr(PgIfAddrCallback callback, void *cb_data)
 309 {
 310         struct ifaddrs *ifa,
 311                            *l;
 312
 313         if (getifaddrs(&ifa) < 0)
 314                 return -1;
 315
 316         for (l = ifa; l; l = l->ifa_next)
 317                 run_ifaddr_callback(callback, cb_data,
 318                                                         l->ifa_addr, l->ifa_netmask);
 319
 320         freeifaddrs(ifa);
 321         return 0;
 322 }
 323 #else                                                   /* !HAVE_GETIFADDRS && !WIN32 */
 324
 325 #include <sys/ioctl.h>
 326
 327 #ifdef HAVE_NET_IF_H
 328 #include <net/if.h>
 329 #endif
 330
 331 #ifdef HAVE_SYS_SOCKIO_H
 332 #include <sys/sockio.h>
 333 #endif
 334
 335 /*
 336  * SIOCGIFCONF does not return IPv6 addresses on Solaris
 337  * and HP/UX. So we prefer SIOCGLIFCONF if it's available.
 338  *
 339  * On HP/UX, however, it *only* returns IPv6 addresses,
 340  * and the structs are named slightly differently too.
 341  * We'd have to do another call with SIOCGIFCONF to get the
 342  * IPv4 addresses as well. We don't currently bother, just
 343  * fall back to SIOCGIFCONF on HP/UX.
 344  */
 345
 346 #if defined(SIOCGLIFCONF) && !defined(__hpux)
 347
 348 /*
 349  * Enumerate the system's network interface addresses and call the callback
 350  * for each one.  Returns 0 if successful, -1 if trouble.
 351  *
 352  * This version uses ioctl(SIOCGLIFCONF).
 353  */
 354 int
 355 pg_foreach_ifaddr(PgIfAddrCallback callback, void *cb_data)
 356 {
 357         struct lifconf lifc;
 358         struct lifreq *lifr,
 359                                 lmask;
 360         struct sockaddr *addr,
 361                            *mask;
 362         char       *ptr,
 363                            *buffer = NULL;
 364         size_t          n_buffer = 1024;
 365         pgsocket        sock,
 366                                 fd;
 367
 368 #ifdef HAVE_IPV6
 369         pgsocket        sock6;
 370 #endif
 371         int                     i,
 372                                 total;
 373
 374         sock = socket(AF_INET, SOCK_DGRAM, 0);
 375         if (sock == PGINVALID_SOCKET)
 376                 return -1;
 377
 378         while (n_buffer < 1024 * 100)
 379         {
 380                 n_buffer += 1024;
 381                 ptr = realloc(buffer, n_buffer);
 382                 if (!ptr)
 383                 {
 384                         free(buffer);
 385                         close(sock);
 386                         errno = ENOMEM;
 387                         return -1;
 388                 }
 389
 390                 memset(&lifc, 0, sizeof(lifc));
 391                 lifc.lifc_family = AF_UNSPEC;
 392                 lifc.lifc_buf = buffer = ptr;
 393                 lifc.lifc_len = n_buffer;
 394
 395                 if (ioctl(sock, SIOCGLIFCONF, &lifc) < 0)
 396                 {
 397                         if (errno == EINVAL)
 398                                 continue;
 399                         free(buffer);
 400                         close(sock);
 401                         return -1;
 402                 }
 403
 404                 /*
 405                  * Some Unixes try to return as much data as possible, with no
 406                  * indication of whether enough space allocated. Don't believe we have
 407                  * it all unless there's lots of slop.
 408                  */
 409                 if (lifc.lifc_len < n_buffer - 1024)
 410                         break;
 411         }
 412
 413 #ifdef HAVE_IPV6
 414         /* We'll need an IPv6 socket too for the SIOCGLIFNETMASK ioctls */
 415         sock6 = socket(AF_INET6, SOCK_DGRAM, 0);
 416         if (sock6 == PGINVALID_SOCKET)
 417         {
 418                 free(buffer);
 419                 close(sock);
 420                 return -1;
 421         }
 422 #endif
 423
 424         total = lifc.lifc_len / sizeof(struct lifreq);
 425         lifr = lifc.lifc_req;
 426         for (i = 0; i < total; ++i)
 427         {
 428                 addr = (struct sockaddr *) &lifr[i].lifr_addr;
 429                 memcpy(&lmask, &lifr[i], sizeof(struct lifreq));
 430 #ifdef HAVE_IPV6
 431                 fd = (addr->sa_family == AF_INET6) ? sock6 : sock;
 432 #else
 433                 fd = sock;
 434 #endif
 435                 if (ioctl(fd, SIOCGLIFNETMASK, &lmask) < 0)
 436                         mask = NULL;
 437                 else
 438                         mask = (struct sockaddr *) &lmask.lifr_addr;
 439                 run_ifaddr_callback(callback, cb_data, addr, mask);
 440         }
 441
 442         free(buffer);
 443         close(sock);
 444 #ifdef HAVE_IPV6
 445         close(sock6);
 446 #endif
 447         return 0;
 448 }
 449 #elif defined(SIOCGIFCONF)
 450
 451 /*
 452  * Remaining Unixes use SIOCGIFCONF. Some only return IPv4 information
 453  * here, so this is the least preferred method. Note that there is no
 454  * standard way to iterate the struct ifreq returned in the array.
 455  * On some OSs the structures are padded large enough for any address,
 456  * on others you have to calculate the size of the struct ifreq.
 457  */
 458
 459 /* Some OSs have _SIZEOF_ADDR_IFREQ, so just use that */
 460 #ifndef _SIZEOF_ADDR_IFREQ
 461
 462 /* Calculate based on sockaddr.sa_len */
 463 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
 464 #define _SIZEOF_ADDR_IFREQ(ifr) \
 465                 ((ifr).ifr_addr.sa_len > sizeof(struct sockaddr) ? \
 466                  (sizeof(struct ifreq) - sizeof(struct sockaddr) + \
 467                   (ifr).ifr_addr.sa_len) : sizeof(struct ifreq))
 468
 469 /* Padded ifreq structure, simple */
 470 #else
 471 #define _SIZEOF_ADDR_IFREQ(ifr) \
 472         sizeof (struct ifreq)
 473 #endif
 474 #endif                                                  /* !_SIZEOF_ADDR_IFREQ */
 475
 476 /*
 477  * Enumerate the system's network interface addresses and call the callback
 478  * for each one.  Returns 0 if successful, -1 if trouble.
 479  *
 480  * This version uses ioctl(SIOCGIFCONF).
 481  */
 482 int
 483 pg_foreach_ifaddr(PgIfAddrCallback callback, void *cb_data)
 484 {
 485         struct ifconf ifc;
 486         struct ifreq *ifr,
 487                            *end,
 488                                 addr,
 489                                 mask;
 490         char       *ptr,
 491                            *buffer = NULL;
 492         size_t          n_buffer = 1024;
 493         pgsocket        sock;
 494
 495         sock = socket(AF_INET, SOCK_DGRAM, 0);
 496         if (sock == PGINVALID_SOCKET)
 497                 return -1;
 498
 499         while (n_buffer < 1024 * 100)
 500         {
 501                 n_buffer += 1024;
 502                 ptr = realloc(buffer, n_buffer);
 503                 if (!ptr)
 504                 {
 505                         free(buffer);
 506                         close(sock);
 507                         errno = ENOMEM;
 508                         return -1;
 509                 }
 510
 511                 memset(&ifc, 0, sizeof(ifc));
 512                 ifc.ifc_buf = buffer = ptr;
 513                 ifc.ifc_len = n_buffer;
 514
 515                 if (ioctl(sock, SIOCGIFCONF, &ifc) < 0)
 516                 {
 517                         if (errno == EINVAL)
 518                                 continue;
 519                         free(buffer);
 520                         close(sock);
 521                         return -1;
 522                 }
 523
 524                 /*
 525                  * Some Unixes try to return as much data as possible, with no
 526                  * indication of whether enough space allocated. Don't believe we have
 527                  * it all unless there's lots of slop.
 528                  */
 529                 if (ifc.ifc_len < n_buffer - 1024)
 530                         break;
 531         }
 532
 533         end = (struct ifreq *) (buffer + ifc.ifc_len);
 534         for (ifr = ifc.ifc_req; ifr < end;)
 535         {
 536                 memcpy(&addr, ifr, sizeof(addr));
 537                 memcpy(&mask, ifr, sizeof(mask));
 538                 if (ioctl(sock, SIOCGIFADDR, &addr, sizeof(addr)) == 0 &&
 539                         ioctl(sock, SIOCGIFNETMASK, &mask, sizeof(mask)) == 0)
 540                         run_ifaddr_callback(callback, cb_data,
 541                                                                 &addr.ifr_addr, &mask.ifr_addr);
 542                 ifr = (struct ifreq *) ((char *) ifr + _SIZEOF_ADDR_IFREQ(*ifr));
 543         }
 544
 545         free(buffer);
 546         close(sock);
 547         return 0;
 548 }
 549 #else                                                   /* !defined(SIOCGIFCONF) */
 550
 551 /*
 552  * Enumerate the system's network interface addresses and call the callback
 553  * for each one.  Returns 0 if successful, -1 if trouble.
 554  *
 555  * This version is our fallback if there's no known way to get the
 556  * interface addresses.  Just return the standard loopback addresses.
 557  */
 558 int
 559 pg_foreach_ifaddr(PgIfAddrCallback callback, void *cb_data)
 560 {
 561         struct sockaddr_in addr;
 562         struct sockaddr_storage mask;
 563
 564 #ifdef HAVE_IPV6
 565         struct sockaddr_in6 addr6;
 566 #endif
 567
 568         /* addr 127.0.0.1/8 */
 569         memset(&addr, 0, sizeof(addr));
 570         addr.sin_family = AF_INET;
 571         addr.sin_addr.s_addr = pg_ntoh32(0x7f000001);
 572         memset(&mask, 0, sizeof(mask));
 573         pg_sockaddr_cidr_mask(&mask, "8", AF_INET);
 574         run_ifaddr_callback(callback, cb_data,
 575                                                 (struct sockaddr *) &addr,
 576                                                 (struct sockaddr *) &mask);
 577
 578 #ifdef HAVE_IPV6
 579         /* addr ::1/128 */
 580         memset(&addr6, 0, sizeof(addr6));
 581         addr6.sin6_family = AF_INET6;
 582         addr6.sin6_addr.s6_addr[15] = 1;
 583         memset(&mask, 0, sizeof(mask));
 584         pg_sockaddr_cidr_mask(&mask, "128", AF_INET6);
 585         run_ifaddr_callback(callback, cb_data,
 586                                                 (struct sockaddr *) &addr6,
 587                                                 (struct sockaddr *) &mask);
 588 #endif
 589
 590         return 0;
 591 }
 592 #endif                                                  /* !defined(SIOCGIFCONF) */
 593
 594 #endif                                                  /* !HAVE_GETIFADDRS */