lib/getaddrinfo.c

   1 /* Get address information (partial implementation).
   2    Copyright (C) 1997, 2001-2002, 2004-2014 Free Software Foundation, Inc.
   3    Contributed by Simon Josefsson <simon@josefsson.org>.
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU Lesser General Public License as published by
   7    the Free Software Foundation; either version 2, or (at your option)
   8    any later version.
   9
  10    This program 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 <http://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 <stdbool.h>
  43
  44 #include "gettext.h"
  45 #define _(String) gettext (String)
  46 #define N_(String) String
  47
  48 /* BeOS has AF_INET, but not PF_INET.  */
  49 #ifndef PF_INET
  50 # define PF_INET AF_INET
  51 #endif
  52 /* BeOS also lacks PF_UNSPEC.  */
  53 #ifndef PF_UNSPEC
  54 # define PF_UNSPEC 0
  55 #endif
  56
  57 #if defined _WIN32 || defined __WIN32__
  58 # define WINDOWS_NATIVE
  59 #endif
  60
  61 /* gl_sockets_startup */
  62 #include "sockets.h"
  63
  64 #ifdef WINDOWS_NATIVE
  65 typedef int (WSAAPI *getaddrinfo_func) (const char*, const char*,
  66                                         const struct addrinfo*,
  67                                         struct addrinfo**);
  68 typedef void (WSAAPI *freeaddrinfo_func) (struct addrinfo*);
  69 typedef int (WSAAPI *getnameinfo_func) (const struct sockaddr*,
  70                                         socklen_t, char*, DWORD,
  71                                         char*, DWORD, int);
  72
  73 static getaddrinfo_func getaddrinfo_ptr = NULL;
  74 static freeaddrinfo_func freeaddrinfo_ptr = NULL;
  75 static getnameinfo_func getnameinfo_ptr = NULL;
  76
  77 static int
  78 use_win32_p (void)
  79 {
  80   static int done = 0;
  81   HMODULE h;
  82
  83   if (done)
  84     return getaddrinfo_ptr ? 1 : 0;
  85
  86   done = 1;
  87
  88   h = GetModuleHandle ("ws2_32.dll");
  89
  90   if (h)
  91     {
  92       getaddrinfo_ptr = (getaddrinfo_func) GetProcAddress (h, "getaddrinfo");
  93       freeaddrinfo_ptr = (freeaddrinfo_func) GetProcAddress (h, "freeaddrinfo");
  94       getnameinfo_ptr = (getnameinfo_func) GetProcAddress (h, "getnameinfo");
  95     }
  96
  97   /* If either is missing, something is odd. */
  98   if (!getaddrinfo_ptr || !freeaddrinfo_ptr || !getnameinfo_ptr)
  99     {
 100       getaddrinfo_ptr = NULL;
 101       freeaddrinfo_ptr = NULL;
 102       getnameinfo_ptr = NULL;
 103       return 0;
 104     }
 105
 106   gl_sockets_startup (SOCKETS_1_1);
 107
 108   return 1;
 109 }
 110 #endif
 111
 112 static bool
 113 validate_family (int family)
 114 {
 115   /* FIXME: Support more families. */
 116 #if HAVE_IPV4
 117      if (family == PF_INET)
 118        return true;
 119 #endif
 120 #if HAVE_IPV6
 121      if (family == PF_INET6)
 122        return true;
 123 #endif
 124      if (family == PF_UNSPEC)
 125        return true;
 126      return false;
 127 }
 128
 129 /* Translate name of a service location and/or a service name to set of
 130    socket addresses. */
 131 int
 132 getaddrinfo (const char *restrict nodename,
 133              const char *restrict servname,
 134              const struct addrinfo *restrict hints,
 135              struct addrinfo **restrict res)
 136 {
 137   struct addrinfo *tmp;
 138   int port = 0;
 139   struct hostent *he;
 140   void *storage;
 141   size_t size;
 142 #if HAVE_IPV6
 143   struct v6_pair {
 144     struct addrinfo addrinfo;
 145     struct sockaddr_in6 sockaddr_in6;
 146   };
 147 #endif
 148 #if HAVE_IPV4
 149   struct v4_pair {
 150     struct addrinfo addrinfo;
 151     struct sockaddr_in sockaddr_in;
 152   };
 153 #endif
 154
 155 #ifdef WINDOWS_NATIVE
 156   if (use_win32_p ())
 157     return getaddrinfo_ptr (nodename, servname, hints, res);
 158 #endif
 159
 160   if (hints && (hints->ai_flags & ~(AI_CANONNAME|AI_PASSIVE)))
 161     /* FIXME: Support more flags. */
 162     return EAI_BADFLAGS;
 163
 164   if (hints && !validate_family (hints->ai_family))
 165     return EAI_FAMILY;
 166
 167   if (hints &&
 168       hints->ai_socktype != SOCK_STREAM && hints->ai_socktype != SOCK_DGRAM)
 169     /* FIXME: Support other socktype. */
 170     return EAI_SOCKTYPE; /* FIXME: Better return code? */
 171
 172   if (!nodename)
 173     {
 174       if (!(hints->ai_flags & AI_PASSIVE))
 175         return EAI_NONAME;
 176
 177 #ifdef HAVE_IPV6
 178       nodename = (hints->ai_family == AF_INET6) ? "::" : "0.0.0.0";
 179 #else
 180       nodename = "0.0.0.0";
 181 #endif
 182     }
 183
 184   if (servname)
 185     {
 186       struct servent *se = NULL;
 187       const char *proto =
 188         (hints && hints->ai_socktype == SOCK_DGRAM) ? "udp" : "tcp";
 189
 190       if (hints == NULL || !(hints->ai_flags & AI_NUMERICSERV))
 191         /* FIXME: Use getservbyname_r if available. */
 192         se = getservbyname (servname, proto);
 193
 194       if (!se)
 195         {
 196           char *c;
 197           if (!(*servname >= '0' && *servname <= '9'))
 198             return EAI_NONAME;
 199           port = strtoul (servname, &c, 10);
 200           if (*c || port > 0xffff)
 201             return EAI_NONAME;
 202           port = htons (port);
 203         }
 204       else
 205         port = se->s_port;
 206     }
 207
 208   /* FIXME: Use gethostbyname_r if available. */
 209   he = gethostbyname (nodename);
 210   if (!he || he->h_addr_list[0] == NULL)
 211     return EAI_NONAME;
 212
 213   switch (he->h_addrtype)
 214     {
 215 #if HAVE_IPV6
 216     case PF_INET6:
 217       size = sizeof (struct v6_pair);
 218       break;
 219 #endif
 220
 221 #if HAVE_IPV4
 222     case PF_INET:
 223       size = sizeof (struct v4_pair);
 224       break;
 225 #endif
 226
 227     default:
 228       return EAI_NODATA;
 229     }
 230
 231   storage = calloc (1, size);
 232   if (!storage)
 233     return EAI_MEMORY;
 234
 235   switch (he->h_addrtype)
 236     {
 237 #if HAVE_IPV6
 238     case PF_INET6:
 239       {
 240         struct v6_pair *p = storage;
 241         struct sockaddr_in6 *sinp = &p->sockaddr_in6;
 242         tmp = &p->addrinfo;
 243
 244         if (port)
 245           sinp->sin6_port = port;
 246
 247         if (he->h_length != sizeof (sinp->sin6_addr))
 248           {
 249             free (storage);
 250             return EAI_SYSTEM; /* FIXME: Better return code?  Set errno? */
 251           }
 252
 253         memcpy (&sinp->sin6_addr, he->h_addr_list[0], sizeof sinp->sin6_addr);
 254
 255         tmp->ai_addr = (struct sockaddr *) sinp;
 256         tmp->ai_addrlen = sizeof *sinp;
 257       }
 258       break;
 259 #endif
 260
 261 #if HAVE_IPV4
 262     case PF_INET:
 263       {
 264         struct v4_pair *p = storage;
 265         struct sockaddr_in *sinp = &p->sockaddr_in;
 266         tmp = &p->addrinfo;
 267
 268         if (port)
 269           sinp->sin_port = port;
 270
 271         if (he->h_length != sizeof (sinp->sin_addr))
 272           {
 273             free (storage);
 274             return EAI_SYSTEM; /* FIXME: Better return code?  Set errno? */
 275           }
 276
 277         memcpy (&sinp->sin_addr, he->h_addr_list[0], sizeof sinp->sin_addr);
 278
 279         tmp->ai_addr = (struct sockaddr *) sinp;
 280         tmp->ai_addrlen = sizeof *sinp;
 281       }
 282       break;
 283 #endif
 284
 285     default:
 286       free (storage);
 287       return EAI_NODATA;
 288     }
 289
 290   if (hints && hints->ai_flags & AI_CANONNAME)
 291     {
 292       const char *cn;
 293       if (he->h_name)
 294         cn = he->h_name;
 295       else
 296         cn = nodename;
 297
 298       tmp->ai_canonname = strdup (cn);
 299       if (!tmp->ai_canonname)
 300         {
 301           free (storage);
 302           return EAI_MEMORY;
 303         }
 304     }
 305
 306   tmp->ai_protocol = (hints) ? hints->ai_protocol : 0;
 307   tmp->ai_socktype = (hints) ? hints->ai_socktype : 0;
 308   tmp->ai_addr->sa_family = he->h_addrtype;
 309   tmp->ai_family = he->h_addrtype;
 310
 311 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
 312   switch (he->h_addrtype)
 313     {
 314 #if HAVE_IPV4
 315     case AF_INET:
 316       tmp->ai_addr->sa_len = sizeof (struct sockaddr_in);
 317       break;
 318 #endif
 319 #if HAVE_IPV6
 320     case AF_INET6:
 321       tmp->ai_addr->sa_len = sizeof (struct sockaddr_in6);
 322       break;
 323 #endif
 324     }
 325 #endif
 326
 327   /* FIXME: If more than one address, create linked list of addrinfo's. */
 328
 329   *res = tmp;
 330
 331   return 0;
 332 }
 333
 334 /* Free 'addrinfo' structure AI including associated storage.  */
 335 void
 336 freeaddrinfo (struct addrinfo *ai)
 337 {
 338 #ifdef WINDOWS_NATIVE
 339   if (use_win32_p ())
 340     {
 341       freeaddrinfo_ptr (ai);
 342       return;
 343     }
 344 #endif
 345
 346   while (ai)
 347     {
 348       struct addrinfo *cur;
 349
 350       cur = ai;
 351       ai = ai->ai_next;
 352
 353       free (cur->ai_canonname);
 354       free (cur);
 355     }
 356 }
 357
 358 int
 359 getnameinfo (const struct sockaddr *restrict sa, socklen_t salen,
 360              char *restrict node, socklen_t nodelen,
 361              char *restrict service, socklen_t servicelen,
 362              int flags)
 363 {
 364 #ifdef WINDOWS_NATIVE
 365   if (use_win32_p ())
 366     return getnameinfo_ptr (sa, salen, node, nodelen,
 367                             service, servicelen, flags);
 368 #endif
 369
 370   /* FIXME: Support other flags. */
 371   if ((node && nodelen > 0 && !(flags & NI_NUMERICHOST)) ||
 372       (service && servicelen > 0 && !(flags & NI_NUMERICHOST)) ||
 373       (flags & ~(NI_NUMERICHOST|NI_NUMERICSERV)))
 374     return EAI_BADFLAGS;
 375
 376   if (sa == NULL || salen < sizeof (sa->sa_family))
 377     return EAI_FAMILY;
 378
 379   switch (sa->sa_family)
 380     {
 381 #if HAVE_IPV4
 382     case AF_INET:
 383       if (salen < sizeof (struct sockaddr_in))
 384         return EAI_FAMILY;
 385       break;
 386 #endif
 387 #if HAVE_IPV6
 388     case AF_INET6:
 389       if (salen < sizeof (struct sockaddr_in6))
 390         return EAI_FAMILY;
 391       break;
 392 #endif
 393     default:
 394       return EAI_FAMILY;
 395     }
 396
 397   if (node && nodelen > 0 && flags & NI_NUMERICHOST)
 398     {
 399       switch (sa->sa_family)
 400         {
 401 #if HAVE_IPV4
 402         case AF_INET:
 403           if (!inet_ntop (AF_INET,
 404                           &(((const struct sockaddr_in *) sa)->sin_addr),
 405                           node, nodelen))
 406             return EAI_SYSTEM;
 407           break;
 408 #endif
 409
 410 #if HAVE_IPV6
 411         case AF_INET6:
 412           if (!inet_ntop (AF_INET6,
 413                           &(((const struct sockaddr_in6 *) sa)->sin6_addr),
 414                           node, nodelen))
 415             return EAI_SYSTEM;
 416           break;
 417 #endif
 418
 419         default:
 420           return EAI_FAMILY;
 421         }
 422     }
 423
 424   if (service && servicelen > 0 && flags & NI_NUMERICSERV)
 425     switch (sa->sa_family)
 426       {
 427 #if HAVE_IPV4
 428       case AF_INET:
 429 #endif
 430 #if HAVE_IPV6
 431       case AF_INET6:
 432 #endif
 433         {
 434           unsigned short int port
 435             = ntohs (((const struct sockaddr_in *) sa)->sin_port);
 436           if (servicelen <= snprintf (service, servicelen, "%u", port))
 437             return EAI_OVERFLOW;
 438         }
 439         break;
 440       }
 441
 442   return 0;
 443 }