gl/getaddrinfo.c

   1 /* Get address information (partial implementation).
   2    Copyright (C) 1997, 2001, 2002, 2004, 2005, 2006, 2007, 2008 Free Software
   3    Foundation, Inc.
   4    Contributed by Simon Josefsson <simon@josefsson.org>.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3, or (at your option)
   9    any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software Foundation,
  18    Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
  19
  20 #include <config.h>
  21
  22 #include <netdb.h>
  23
  24 #if HAVE_NETINET_IN_H
  25 # include <netinet/in.h>
  26 #endif
  27
  28 /* Get inet_ntop.  */
  29 #include <arpa/inet.h>
  30
  31 /* Get calloc. */
  32 #include <stdlib.h>
  33
  34 /* Get memcpy, strdup. */
  35 #include <string.h>
  36
  37 /* Get snprintf. */
  38 #include <stdio.h>
  39
  40 #include <stdbool.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 defined _WIN32 || defined __WIN32__
  56 # define WIN32_NATIVE
  57 #endif
  58
  59 #ifdef WIN32_NATIVE
  60 typedef int (WSAAPI *getaddrinfo_func) (const char*, const char*,
  61                                         const struct addrinfo*,
  62                                         struct addrinfo**);
  63 typedef void (WSAAPI *freeaddrinfo_func) (struct addrinfo*);
  64 typedef int (WSAAPI *getnameinfo_func) (const struct sockaddr*,
  65                                         socklen_t, char*, DWORD,
  66                                         char*, DWORD, int);
  67
  68 static getaddrinfo_func getaddrinfo_ptr = NULL;
  69 static freeaddrinfo_func freeaddrinfo_ptr = NULL;
  70 static getnameinfo_func getnameinfo_ptr = NULL;
  71
  72 static int
  73 use_win32_p (void)
  74 {
  75   static int done = 0;
  76   HMODULE h;
  77
  78   if (done)
  79     return getaddrinfo_ptr ? 1 : 0;
  80
  81   done = 1;
  82
  83   h = GetModuleHandle ("ws2_32.dll");
  84
  85   if (h)
  86     {
  87       getaddrinfo_ptr = (getaddrinfo_func) GetProcAddress (h, "getaddrinfo");
  88       freeaddrinfo_ptr = (freeaddrinfo_func) GetProcAddress (h, "freeaddrinfo");
  89       getnameinfo_ptr = (getnameinfo_func) GetProcAddress (h, "getnameinfo");
  90     }
  91
  92   /* If either is missing, something is odd. */
  93   if (!getaddrinfo_ptr || !freeaddrinfo_ptr || !getnameinfo_ptr)
  94     {
  95       getaddrinfo_ptr = NULL;
  96       freeaddrinfo_ptr = NULL;
  97       getnameinfo_ptr = NULL;
  98       return 0;
  99     }
 100
 101   return 1;
 102 }
 103 #endif
 104
 105 static inline bool
 106 validate_family (int family)
 107 {
 108   /* FIXME: Support more families. */
 109 #if HAVE_IPV4
 110      if (family == PF_INET)
 111        return true;
 112 #endif
 113 #if HAVE_IPV6
 114      if (family == PF_INET6)
 115        return true;
 116 #endif
 117      if (family == PF_UNSPEC)
 118        return true;
 119      return false;
 120 }
 121
 122 /* Translate name of a service location and/or a service name to set of
 123    socket addresses. */
 124 int
 125 getaddrinfo (const char *restrict nodename,
 126              const char *restrict servname,
 127              const struct addrinfo *restrict hints,
 128              struct addrinfo **restrict res)
 129 {
 130   struct addrinfo *tmp;
 131   int port = 0;
 132   struct hostent *he;
 133   void *storage;
 134   size_t size;
 135 #if HAVE_IPV6
 136   struct v6_pair {
 137     struct addrinfo addrinfo;
 138     struct sockaddr_in6 sockaddr_in6;
 139   };
 140 #endif
 141 #if HAVE_IPV4
 142   struct v4_pair {
 143     struct addrinfo addrinfo;
 144     struct sockaddr_in sockaddr_in;
 145   };
 146 #endif
 147
 148 #ifdef WIN32_NATIVE
 149   if (use_win32_p ())
 150     return getaddrinfo_ptr (nodename, servname, hints, res);
 151 #endif
 152
 153   if (hints && (hints->ai_flags & ~(AI_CANONNAME|AI_PASSIVE)))
 154     /* FIXME: Support more flags. */
 155     return EAI_BADFLAGS;
 156
 157   if (hints && !validate_family (hints->ai_family))
 158     return EAI_FAMILY;
 159
 160   if (hints &&
 161       hints->ai_socktype != SOCK_STREAM && hints->ai_socktype != SOCK_DGRAM)
 162     /* FIXME: Support other socktype. */
 163     return EAI_SOCKTYPE; /* FIXME: Better return code? */
 164
 165   if (!nodename)
 166     {
 167       if (!(hints->ai_flags & AI_PASSIVE))
 168         return EAI_NONAME;
 169
 170 #ifdef HAVE_IPV6
 171       nodename = (hints->ai_family == AF_INET6) ? "::" : "0.0.0.0";
 172 #else
 173       nodename = "0.0.0.0";
 174 #endif
 175     }
 176
 177   if (servname)
 178     {
 179       struct servent *se = NULL;
 180       const char *proto =
 181         (hints && hints->ai_socktype == SOCK_DGRAM) ? "udp" : "tcp";
 182
 183       if (hints == NULL || !(hints->ai_flags & AI_NUMERICSERV))
 184         /* FIXME: Use getservbyname_r if available. */
 185         se = getservbyname (servname, proto);
 186
 187       if (!se)
 188         {
 189           char *c;
 190           if (!(*servname >= '0' && *servname <= '9'))
 191             return EAI_NONAME;
 192           port = strtoul (servname, &c, 10);
 193           if (*c || port > 0xffff)
 194             return EAI_NONAME;
 195           port = htons (port);
 196         }
 197       else
 198         port = se->s_port;
 199     }
 200
 201   /* FIXME: Use gethostbyname_r if available. */
 202   he = gethostbyname (nodename);
 203   if (!he || he->h_addr_list[0] == NULL)
 204     return EAI_NONAME;
 205
 206   switch (he->h_addrtype)
 207     {
 208 #if HAVE_IPV6
 209     case PF_INET6:
 210       size = sizeof (struct v6_pair);
 211       break;
 212 #endif
 213
 214 #if HAVE_IPV4
 215     case PF_INET:
 216       size = sizeof (struct v4_pair);
 217       break;
 218 #endif
 219
 220     default:
 221       return EAI_NODATA;
 222     }
 223
 224   storage = calloc (1, size);
 225   if (!storage)
 226     return EAI_MEMORY;
 227
 228   switch (he->h_addrtype)
 229     {
 230 #if HAVE_IPV6
 231     case PF_INET6:
 232       {
 233         struct v6_pair *p = storage;
 234         struct sockaddr_in6 *sinp = &p->sockaddr_in6;
 235         tmp = &p->addrinfo;
 236
 237         if (port)
 238           sinp->sin6_port = port;
 239
 240         if (he->h_length != sizeof (sinp->sin6_addr))
 241           {
 242             free (storage);
 243             return EAI_SYSTEM; /* FIXME: Better return code?  Set errno? */
 244           }
 245
 246         memcpy (&sinp->sin6_addr, he->h_addr_list[0], sizeof sinp->sin6_addr);
 247
 248         tmp->ai_addr = (struct sockaddr *) sinp;
 249         tmp->ai_addrlen = sizeof *sinp;
 250       }
 251       break;
 252 #endif
 253
 254 #if HAVE_IPV4
 255     case PF_INET:
 256       {
 257         struct v4_pair *p = storage;
 258         struct sockaddr_in *sinp = &p->sockaddr_in;
 259         tmp = &p->addrinfo;
 260
 261         if (port)
 262           sinp->sin_port = port;
 263
 264         if (he->h_length != sizeof (sinp->sin_addr))
 265           {
 266             free (storage);
 267             return EAI_SYSTEM; /* FIXME: Better return code?  Set errno? */
 268           }
 269
 270         memcpy (&sinp->sin_addr, he->h_addr_list[0], sizeof sinp->sin_addr);
 271
 272         tmp->ai_addr = (struct sockaddr *) sinp;
 273         tmp->ai_addrlen = sizeof *sinp;
 274       }
 275       break;
 276 #endif
 277
 278     default:
 279       free (storage);
 280       return EAI_NODATA;
 281     }
 282
 283   if (hints && hints->ai_flags & AI_CANONNAME)
 284     {
 285       const char *cn;
 286       if (he->h_name)
 287         cn = he->h_name;
 288       else
 289         cn = nodename;
 290
 291       tmp->ai_canonname = strdup (cn);
 292       if (!tmp->ai_canonname)
 293         {
 294           free (storage);
 295           return EAI_MEMORY;
 296         }
 297     }
 298
 299   tmp->ai_protocol = (hints) ? hints->ai_protocol : 0;
 300   tmp->ai_socktype = (hints) ? hints->ai_socktype : 0;
 301   tmp->ai_addr->sa_family = he->h_addrtype;
 302   tmp->ai_family = he->h_addrtype;
 303
 304 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
 305   switch (he->h_addrtype)
 306     {
 307 #if HAVE_IPV4
 308     case AF_INET:
 309       tmp->ai_addr->sa_len = sizeof (struct sockaddr_in);
 310       break;
 311 #endif
 312 #if HAVE_IPV6
 313     case AF_INET6:
 314       tmp->ai_addr->sa_len = sizeof (struct sockaddr_in6);
 315       break;
 316 #endif
 317     }
 318 #endif
 319
 320   /* FIXME: If more than one address, create linked list of addrinfo's. */
 321
 322   *res = tmp;
 323
 324   return 0;
 325 }
 326
 327 /* Free `addrinfo' structure AI including associated storage.  */
 328 void
 329 freeaddrinfo (struct addrinfo *ai)
 330 {
 331 #ifdef WIN32_NATIVE
 332   if (use_win32_p ())
 333     {
 334       freeaddrinfo_ptr (ai);
 335       return;
 336     }
 337 #endif
 338
 339   while (ai)
 340     {
 341       struct addrinfo *cur;
 342
 343       cur = ai;
 344       ai = ai->ai_next;
 345
 346       free (cur->ai_canonname);
 347       free (cur);
 348     }
 349 }
 350
 351 int getnameinfo(const struct sockaddr *restrict sa, socklen_t salen,
 352                 char *restrict node, socklen_t nodelen,
 353                 char *restrict service, socklen_t servicelen,
 354                 int flags)
 355 {
 356 #ifdef WIN32_NATIVE
 357   if (use_win32_p ())
 358     return getnameinfo_ptr (sa, salen, node, nodelen,
 359                             service, servicelen, flags);
 360 #endif
 361
 362   /* FIXME: Support other flags. */
 363   if ((node && nodelen > 0 && !(flags & NI_NUMERICHOST)) ||
 364       (service && servicelen > 0 && !(flags & NI_NUMERICHOST)) ||
 365       (flags & ~(NI_NUMERICHOST|NI_NUMERICSERV)))
 366     return EAI_BADFLAGS;
 367
 368   if (sa == NULL || salen < sizeof (sa->sa_family))
 369     return EAI_FAMILY;
 370
 371   switch (sa->sa_family)
 372     {
 373 #if HAVE_IPV4
 374     case AF_INET:
 375       if (salen < sizeof (struct sockaddr_in))
 376         return EAI_FAMILY;
 377       break;
 378 #endif
 379 #if HAVE_IPV6
 380     case AF_INET6:
 381       if (salen < sizeof (struct sockaddr_in6))
 382         return EAI_FAMILY;
 383       break;
 384 #endif
 385     default:
 386       return EAI_FAMILY;
 387     }
 388
 389   if (node && nodelen > 0 && flags & NI_NUMERICHOST)
 390     {
 391       switch (sa->sa_family)
 392         {
 393 #if HAVE_IPV4
 394         case AF_INET:
 395           if (!inet_ntop (AF_INET,
 396                           &(((const struct sockaddr_in *) sa)->sin_addr),
 397                           node, nodelen))
 398             return EAI_SYSTEM;
 399           break;
 400 #endif
 401
 402 #if HAVE_IPV6
 403         case AF_INET6:
 404           if (!inet_ntop (AF_INET6,
 405                           &(((const struct sockaddr_in6 *) sa)->sin6_addr),
 406                           node, nodelen))
 407             return EAI_SYSTEM;
 408           break;
 409 #endif
 410
 411         default:
 412           return EAI_FAMILY;
 413         }
 414     }
 415
 416   if (service && servicelen > 0 && flags & NI_NUMERICSERV)
 417     switch (sa->sa_family)
 418       {
 419 #if HAVE_IPV4
 420       case AF_INET:
 421 #endif
 422 #if HAVE_IPV6
 423       case AF_INET6:
 424 #endif
 425         {
 426           unsigned short int port
 427             = ntohs (((const struct sockaddr_in *) sa)->sin_port);
 428           if (servicelen <= snprintf (service, servicelen, "%u", port))
 429             return EAI_OVERFLOW;
 430         }
 431         break;
 432       }
 433
 434   return 0;
 435 }