gl/getaddrinfo.c

   1 /* Get address information (partial implementation).
   2    Copyright (C) 1997, 2001-2002, 2004-2023 Free Software Foundation, Inc.
   3    Contributed by Simon Josefsson <simon@josefsson.org>.
   4
   5    This file is free software: you can redistribute it and/or modify
   6    it under the terms of the GNU Lesser General Public License as
   7    published by the Free Software Foundation; either version 2.1 of the
   8    License, or (at your option) any later version.
   9
  10    This file is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public License
  16    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  17
  18 /* Don't use __attribute__ __nonnull__ in this compilation unit.  Otherwise gcc
  19    optimizes away the sa == NULL test below.  */
  20 #define _GL_ARG_NONNULL(params)
  21
  22 #include <config.h>
  23
  24 #include <netdb.h>
  25
  26 #if HAVE_NETINET_IN_H
  27 # include <netinet/in.h>
  28 #endif
  29
  30 /* Get inet_ntop.  */
  31 #include <arpa/inet.h>
  32
  33 /* Get calloc. */
  34 #include <stdlib.h>
  35
  36 /* Get memcpy, strdup. */
  37 #include <string.h>
  38
  39 /* Get snprintf. */
  40 #include <stdio.h>
  41
  42 #include "gettext.h"
  43 #define _(String) gettext (String)
  44 #define N_(String) String
  45
  46 /* BeOS has AF_INET, but not PF_INET.  */
  47 #ifndef PF_INET
  48 # define PF_INET AF_INET
  49 #endif
  50 /* BeOS also lacks PF_UNSPEC.  */
  51 #ifndef PF_UNSPEC
  52 # define PF_UNSPEC 0
  53 #endif
  54
  55 #if HAVE_GETADDRINFO
  56
  57 /* Override with cdecl calling convention.  */
  58
  59 int
  60 getaddrinfo (const char *restrict nodename,
  61              const char *restrict servname,
  62              const struct addrinfo *restrict hints,
  63              struct addrinfo **restrict res)
  64 # undef getaddrinfo
  65 {
  66   return getaddrinfo (nodename, servname, hints, res);
  67 }
  68
  69 void
  70 freeaddrinfo (struct addrinfo *ai)
  71 # undef freeaddrinfo
  72 {
  73   freeaddrinfo (ai);
  74 }
  75
  76 #else
  77
  78 # if defined _WIN32 && !defined __CYGWIN__
  79 #  define WINDOWS_NATIVE
  80 # endif
  81
  82 /* gl_sockets_startup */
  83 # include "sockets.h"
  84
  85 # ifdef WINDOWS_NATIVE
  86
  87 /* Don't assume that UNICODE is not defined.  */
  88 #  undef GetModuleHandle
  89 #  define GetModuleHandle GetModuleHandleA
  90
  91 #  if !(_WIN32_WINNT >= _WIN32_WINNT_WINXP)
  92
  93 /* Avoid warnings from gcc -Wcast-function-type.  */
  94 #   define GetProcAddress \
  95      (void *) GetProcAddress
  96
  97 typedef int (WSAAPI *getaddrinfo_func) (const char*, const char*,
  98                                         const struct addrinfo*,
  99                                         struct addrinfo**);
 100 typedef void (WSAAPI *freeaddrinfo_func) (struct addrinfo*);
 101 typedef int (WSAAPI *getnameinfo_func) (const struct sockaddr*,
 102                                         socklen_t, char*, DWORD,
 103                                         char*, DWORD, int);
 104
 105 static getaddrinfo_func getaddrinfo_ptr = NULL;
 106 static freeaddrinfo_func freeaddrinfo_ptr = NULL;
 107 static getnameinfo_func getnameinfo_ptr = NULL;
 108
 109 static int
 110 use_win32_p (void)
 111 {
 112   static int done = 0;
 113   HMODULE h;
 114
 115   if (done)
 116     return getaddrinfo_ptr ? 1 : 0;
 117
 118   done = 1;
 119
 120   h = GetModuleHandle ("ws2_32.dll");
 121
 122   if (h)
 123     {
 124       getaddrinfo_ptr = (getaddrinfo_func) GetProcAddress (h, "getaddrinfo");
 125       freeaddrinfo_ptr = (freeaddrinfo_func) GetProcAddress (h, "freeaddrinfo");
 126       getnameinfo_ptr = (getnameinfo_func) GetProcAddress (h, "getnameinfo");
 127     }
 128
 129   /* If either is missing, something is odd. */
 130   if (!getaddrinfo_ptr || !freeaddrinfo_ptr || !getnameinfo_ptr)
 131     {
 132       getaddrinfo_ptr = NULL;
 133       freeaddrinfo_ptr = NULL;
 134       getnameinfo_ptr = NULL;
 135       return 0;
 136     }
 137
 138   gl_sockets_startup (SOCKETS_1_1);
 139
 140   return 1;
 141 }
 142
 143 #  else
 144
 145 static int
 146 use_win32_p (void)
 147 {
 148   static int done = 0;
 149
 150   if (!done)
 151     {
 152       done = 1;
 153
 154       gl_sockets_startup (SOCKETS_1_1);
 155     }
 156
 157   return 1;
 158 }
 159
 160 #   define getaddrinfo_ptr getaddrinfo
 161 #   define freeaddrinfo_ptr freeaddrinfo
 162 #   define getnameinfo_ptr getnameinfo
 163
 164 #  endif
 165 # endif
 166
 167 static bool
 168 validate_family (int family)
 169 {
 170   /* FIXME: Support more families. */
 171 # if HAVE_IPV4
 172      if (family == PF_INET)
 173        return true;
 174 # endif
 175 # if HAVE_IPV6
 176      if (family == PF_INET6)
 177        return true;
 178 # endif
 179      if (family == PF_UNSPEC)
 180        return true;
 181      return false;
 182 }
 183
 184 /* Translate name of a service location and/or a service name to set of
 185    socket addresses. */
 186 int
 187 getaddrinfo (const char *restrict nodename,
 188              const char *restrict servname,
 189              const struct addrinfo *restrict hints,
 190              struct addrinfo **restrict res)
 191 #undef getaddrinfo
 192 {
 193   struct addrinfo *tmp;
 194   int port = 0;
 195   struct hostent *he;
 196   void *storage;
 197   size_t size;
 198 # if HAVE_IPV6
 199   struct v6_pair {
 200     struct addrinfo addrinfo;
 201     struct sockaddr_in6 sockaddr_in6;
 202   };
 203 # endif
 204 # if HAVE_IPV4
 205   struct v4_pair {
 206     struct addrinfo addrinfo;
 207     struct sockaddr_in sockaddr_in;
 208   };
 209 # endif
 210
 211 # ifdef WINDOWS_NATIVE
 212   if (use_win32_p ())
 213     return getaddrinfo_ptr (nodename, servname, hints, res);
 214 # endif
 215
 216   if (hints && (hints->ai_flags & ~(AI_CANONNAME|AI_PASSIVE)))
 217     /* FIXME: Support more flags. */
 218     return EAI_BADFLAGS;
 219
 220   if (hints && !validate_family (hints->ai_family))
 221     return EAI_FAMILY;
 222
 223   if (hints &&
 224       hints->ai_socktype != SOCK_STREAM && hints->ai_socktype != SOCK_DGRAM)
 225     /* FIXME: Support other socktype. */
 226     return EAI_SOCKTYPE; /* FIXME: Better return code? */
 227
 228   if (!nodename)
 229     {
 230       if (!(hints->ai_flags & AI_PASSIVE))
 231         return EAI_NONAME;
 232
 233 # ifdef HAVE_IPV6
 234       nodename = (hints->ai_family == AF_INET6) ? "::" : "0.0.0.0";
 235 # else
 236       nodename = "0.0.0.0";
 237 # endif
 238     }
 239
 240   if (servname)
 241     {
 242       struct servent *se = NULL;
 243       const char *proto =
 244         (hints && hints->ai_socktype == SOCK_DGRAM) ? "udp" : "tcp";
 245
 246       if (hints == NULL || !(hints->ai_flags & AI_NUMERICSERV))
 247         /* FIXME: Use getservbyname_r if available. */
 248         se = getservbyname (servname, proto);
 249
 250       if (!se)
 251         {
 252           char *c;
 253           if (!(*servname >= '0' && *servname <= '9'))
 254             return EAI_NONAME;
 255           port = strtoul (servname, &c, 10);
 256           if (*c || port > 0xffff)
 257             return EAI_NONAME;
 258           port = htons (port);
 259         }
 260       else
 261         port = se->s_port;
 262     }
 263
 264   /* FIXME: Use gethostbyname_r if available. */
 265   he = gethostbyname (nodename);
 266   if (!he || he->h_addr_list[0] == NULL)
 267     return EAI_NONAME;
 268
 269   switch (he->h_addrtype)
 270     {
 271 # if HAVE_IPV6
 272     case PF_INET6:
 273       size = sizeof (struct v6_pair);
 274       break;
 275 # endif
 276
 277 # if HAVE_IPV4
 278     case PF_INET:
 279       size = sizeof (struct v4_pair);
 280       break;
 281 # endif
 282
 283     default:
 284       return EAI_NODATA;
 285     }
 286
 287   storage = calloc (1, size);
 288   if (!storage)
 289     return EAI_MEMORY;
 290
 291   switch (he->h_addrtype)
 292     {
 293 # if HAVE_IPV6
 294     case PF_INET6:
 295       {
 296         struct v6_pair *p = storage;
 297         struct sockaddr_in6 *sinp = &p->sockaddr_in6;
 298         tmp = &p->addrinfo;
 299
 300         if (port)
 301           sinp->sin6_port = port;
 302
 303         if (he->h_length != sizeof (sinp->sin6_addr))
 304           {
 305             free (storage);
 306             return EAI_SYSTEM; /* FIXME: Better return code?  Set errno? */
 307           }
 308
 309         memcpy (&sinp->sin6_addr, he->h_addr_list[0], sizeof sinp->sin6_addr);
 310
 311         tmp->ai_addr = (struct sockaddr *) sinp;
 312         tmp->ai_addrlen = sizeof *sinp;
 313       }
 314       break;
 315 # endif
 316
 317 # if HAVE_IPV4
 318     case PF_INET:
 319       {
 320         struct v4_pair *p = storage;
 321         struct sockaddr_in *sinp = &p->sockaddr_in;
 322         tmp = &p->addrinfo;
 323
 324         if (port)
 325           sinp->sin_port = port;
 326
 327         if (he->h_length != sizeof (sinp->sin_addr))
 328           {
 329             free (storage);
 330             return EAI_SYSTEM; /* FIXME: Better return code?  Set errno? */
 331           }
 332
 333         memcpy (&sinp->sin_addr, he->h_addr_list[0], sizeof sinp->sin_addr);
 334
 335         tmp->ai_addr = (struct sockaddr *) sinp;
 336         tmp->ai_addrlen = sizeof *sinp;
 337       }
 338       break;
 339 # endif
 340
 341     default:
 342       free (storage);
 343       return EAI_NODATA;
 344     }
 345
 346   if (hints && hints->ai_flags & AI_CANONNAME)
 347     {
 348       const char *cn;
 349       if (he->h_name)
 350         cn = he->h_name;
 351       else
 352         cn = nodename;
 353
 354       tmp->ai_canonname = strdup (cn);
 355       if (!tmp->ai_canonname)
 356         {
 357           free (storage);
 358           return EAI_MEMORY;
 359         }
 360     }
 361
 362   tmp->ai_protocol = (hints) ? hints->ai_protocol : 0;
 363   tmp->ai_socktype = (hints) ? hints->ai_socktype : 0;
 364   tmp->ai_addr->sa_family = he->h_addrtype;
 365   tmp->ai_family = he->h_addrtype;
 366
 367 # ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
 368   switch (he->h_addrtype)
 369     {
 370 #  if HAVE_IPV4
 371     case AF_INET:
 372       tmp->ai_addr->sa_len = sizeof (struct sockaddr_in);
 373       break;
 374 #  endif
 375 #  if HAVE_IPV6
 376     case AF_INET6:
 377       tmp->ai_addr->sa_len = sizeof (struct sockaddr_in6);
 378       break;
 379 #  endif
 380     }
 381 # endif
 382
 383   /* FIXME: If more than one address, create linked list of addrinfo's. */
 384
 385   *res = tmp;
 386
 387   return 0;
 388 }
 389
 390 /* Free 'addrinfo' structure AI including associated storage.  */
 391 void
 392 freeaddrinfo (struct addrinfo *ai)
 393 #undef freeaddrinfo
 394 {
 395 # ifdef WINDOWS_NATIVE
 396   if (use_win32_p ())
 397     {
 398       freeaddrinfo_ptr (ai);
 399       return;
 400     }
 401 # endif
 402
 403   while (ai)
 404     {
 405       struct addrinfo *cur;
 406
 407       cur = ai;
 408       ai = ai->ai_next;
 409
 410       free (cur->ai_canonname);
 411       free (cur);
 412     }
 413 }
 414
 415 int
 416 getnameinfo (const struct sockaddr *restrict sa, socklen_t salen,
 417              char *restrict node, socklen_t nodelen,
 418              char *restrict service, socklen_t servicelen,
 419              int flags)
 420 #undef getnameinfo
 421 {
 422 # ifdef WINDOWS_NATIVE
 423   if (use_win32_p ())
 424     return getnameinfo_ptr (sa, salen, node, nodelen,
 425                             service, servicelen, flags);
 426 # endif
 427
 428   /* FIXME: Support other flags. */
 429   if ((node && nodelen > 0 && !(flags & NI_NUMERICHOST)) ||
 430       (service && servicelen > 0 && !(flags & NI_NUMERICHOST)) ||
 431       (flags & ~(NI_NUMERICHOST|NI_NUMERICSERV)))
 432     return EAI_BADFLAGS;
 433
 434   if (sa == NULL || salen < sizeof (sa->sa_family))
 435     return EAI_FAMILY;
 436
 437   switch (sa->sa_family)
 438     {
 439 # if HAVE_IPV4
 440     case AF_INET:
 441       if (salen < sizeof (struct sockaddr_in))
 442         return EAI_FAMILY;
 443       break;
 444 # endif
 445 # if HAVE_IPV6
 446     case AF_INET6:
 447       if (salen < sizeof (struct sockaddr_in6))
 448         return EAI_FAMILY;
 449       break;
 450 # endif
 451     default:
 452       return EAI_FAMILY;
 453     }
 454
 455   if (node && nodelen > 0 && flags & NI_NUMERICHOST)
 456     {
 457       switch (sa->sa_family)
 458         {
 459 # if HAVE_IPV4
 460         case AF_INET:
 461           if (!inet_ntop (AF_INET,
 462                           &(((const struct sockaddr_in *) sa)->sin_addr),
 463                           node, nodelen))
 464             return EAI_SYSTEM;
 465           break;
 466 # endif
 467
 468 # if HAVE_IPV6
 469         case AF_INET6:
 470           if (!inet_ntop (AF_INET6,
 471                           &(((const struct sockaddr_in6 *) sa)->sin6_addr),
 472                           node, nodelen))
 473             return EAI_SYSTEM;
 474           break;
 475 # endif
 476
 477         default:
 478           return EAI_FAMILY;
 479         }
 480     }
 481
 482   if (service && servicelen > 0 && flags & NI_NUMERICSERV)
 483     switch (sa->sa_family)
 484       {
 485 # if HAVE_IPV4
 486       case AF_INET:
 487 # endif
 488 # if HAVE_IPV6
 489       case AF_INET6:
 490 # endif
 491         {
 492           unsigned short int port
 493             = ntohs (((const struct sockaddr_in *) sa)->sin_port);
 494           if (servicelen <= snprintf (service, servicelen, "%u", port))
 495             return EAI_OVERFLOW;
 496         }
 497         break;
 498       }
 499
 500   return 0;
 501 }
 502
 503 #endif