gl/getaddrinfo.c

   1 /* Get address information (partial implementation).
   2    Copyright (C) 1997, 2001, 2002, 2004, 2005, 2006, 2007 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 "getaddrinfo.h"
  23
  24 #if HAVE_NETINET_IN_H
  25 # include <netinet/in.h>
  26 #endif
  27
  28 /* Get calloc. */
  29 #include <stdlib.h>
  30
  31 /* Get memcpy, strdup. */
  32 #include <string.h>
  33
  34 /* Get snprintf. */
  35 #include <stdio.h>
  36
  37 #include <stdbool.h>
  38
  39 #include "gettext.h"
  40 #define _(String) gettext (String)
  41 #define N_(String) String
  42
  43 #include "inet_ntop.h"
  44
  45 /* BeOS has AF_INET, but not PF_INET.  */
  46 #ifndef PF_INET
  47 # define PF_INET AF_INET
  48 #endif
  49 /* BeOS also lacks PF_UNSPEC.  */
  50 #ifndef PF_UNSPEC
  51 # define PF_UNSPEC 0
  52 #endif
  53
  54 #if defined _WIN32 || defined __WIN32__
  55 # define WIN32_NATIVE
  56 #endif
  57
  58 #ifdef WIN32_NATIVE
  59 typedef int (WSAAPI *getaddrinfo_func) (const char*, const char*,
  60                                         const struct addrinfo*,
  61                                         struct addrinfo**);
  62 typedef void (WSAAPI *freeaddrinfo_func) (struct addrinfo*);
  63 typedef int (WSAAPI *getnameinfo_func) (const struct sockaddr*,
  64                                         socklen_t, char*, DWORD,
  65                                         char*, DWORD, int);
  66
  67 static getaddrinfo_func getaddrinfo_ptr = NULL;
  68 static freeaddrinfo_func freeaddrinfo_ptr = NULL;
  69 static getnameinfo_func getnameinfo_ptr = NULL;
  70
  71 static int
  72 use_win32_p (void)
  73 {
  74   static int done = 0;
  75   HMODULE h;
  76
  77   if (done)
  78     return getaddrinfo_ptr ? 1 : 0;
  79
  80   done = 1;
  81
  82   h = GetModuleHandle ("ws2_32.dll");
  83
  84   if (h)
  85     {
  86       getaddrinfo_ptr = (getaddrinfo_func) GetProcAddress (h, "getaddrinfo");
  87       freeaddrinfo_ptr = (freeaddrinfo_func) GetProcAddress (h, "freeaddrinfo");
  88       getnameinfo_ptr = (getnameinfo_func) GetProcAddress (h, "getnameinfo");
  89     }
  90
  91   /* If either is missing, something is odd. */
  92   if (!getaddrinfo_ptr || !freeaddrinfo_ptr || !getnameinfo_ptr)
  93     {
  94       getaddrinfo_ptr = NULL;
  95       freeaddrinfo_ptr = NULL;
  96       getnameinfo_ptr = NULL;
  97       return 0;
  98     }
  99
 100   return 1;
 101 }
 102 #endif
 103
 104 static inline bool
 105 validate_family (int family)
 106 {
 107   /* FIXME: Support more families. */
 108 #if HAVE_IPV4
 109      if (family == PF_INET)
 110        return true;
 111 #endif
 112 #if HAVE_IPV6
 113      if (family == PF_INET6)
 114        return true;
 115 #endif
 116      if (family == PF_UNSPEC)
 117        return true;
 118      return false;
 119 }
 120
 121 /* Translate name of a service location and/or a service name to set of
 122    socket addresses. */
 123 int
 124 getaddrinfo (const char *restrict nodename,
 125              const char *restrict servname,
 126              const struct addrinfo *restrict hints,
 127              struct addrinfo **restrict res)
 128 {
 129   struct addrinfo *tmp;
 130   int port = 0;
 131   struct hostent *he;
 132   void *storage;
 133   size_t size;
 134 #if HAVE_IPV6
 135   struct v6_pair {
 136     struct addrinfo addrinfo;
 137     struct sockaddr_in6 sockaddr_in6;
 138   };
 139 #endif
 140 #if HAVE_IPV4
 141   struct v4_pair {
 142     struct addrinfo addrinfo;
 143     struct sockaddr_in sockaddr_in;
 144   };
 145 #endif
 146
 147 #ifdef WIN32_NATIVE
 148   if (use_win32_p ())
 149     return getaddrinfo_ptr (nodename, servname, hints, res);
 150 #endif
 151
 152   if (hints && (hints->ai_flags & ~(AI_CANONNAME|AI_PASSIVE)))
 153     /* FIXME: Support more flags. */
 154     return EAI_BADFLAGS;
 155
 156   if (hints && !validate_family (hints->ai_family))
 157     return EAI_FAMILY;
 158
 159   if (hints &&
 160       hints->ai_socktype != SOCK_STREAM && hints->ai_socktype != SOCK_DGRAM)
 161     /* FIXME: Support other socktype. */
 162     return EAI_SOCKTYPE; /* FIXME: Better return code? */
 163
 164   if (!nodename)
 165     {
 166       if (!(hints->ai_flags & AI_PASSIVE))
 167         return EAI_NONAME;
 168
 169 #ifdef HAVE_IPV6
 170       nodename = (hints->ai_family == AF_INET6) ? "::" : "0.0.0.0";
 171 #else
 172       nodename = "0.0.0.0";
 173 #endif
 174     }
 175
 176   if (servname)
 177     {
 178       struct servent *se = NULL;
 179       const char *proto =
 180         (hints && hints->ai_socktype == SOCK_DGRAM) ? "udp" : "tcp";
 181
 182       if (hints == NULL || !(hints->ai_flags & AI_NUMERICSERV))
 183         /* FIXME: Use getservbyname_r if available. */
 184         se = getservbyname (servname, proto);
 185
 186       if (!se)
 187         {
 188           char *c;
 189           if (!(*servname >= '0' && *servname <= '9'))
 190             return EAI_NONAME;
 191           port = strtoul (servname, &c, 10);
 192           if (*c || port > 0xffff)
 193             return EAI_NONAME;
 194           port = htons (port);
 195         }
 196       else
 197         port = se->s_port;
 198     }
 199
 200   /* FIXME: Use gethostbyname_r if available. */
 201   he = gethostbyname (nodename);
 202   if (!he || he->h_addr_list[0] == NULL)
 203     return EAI_NONAME;
 204
 205   switch (he->h_addrtype)
 206     {
 207 #if HAVE_IPV6
 208     case PF_INET6:
 209       size = sizeof (struct v6_pair);
 210       break;
 211 #endif
 212
 213 #if HAVE_IPV4
 214     case PF_INET:
 215       size = sizeof (struct v4_pair);
 216       break;
 217 #endif
 218
 219     default:
 220       return EAI_NODATA;
 221     }
 222
 223   storage = calloc (1, size);
 224   if (!storage)
 225     return EAI_MEMORY;
 226
 227   switch (he->h_addrtype)
 228     {
 229 #if HAVE_IPV6
 230     case PF_INET6:
 231       {
 232         struct v6_pair *p = storage;
 233         struct sockaddr_in6 *sinp = &p->sockaddr_in6;
 234         tmp = &p->addrinfo;
 235
 236         if (port)
 237           sinp->sin6_port = port;
 238
 239         if (he->h_length != sizeof (sinp->sin6_addr))
 240           {
 241             free (storage);
 242             return EAI_SYSTEM; /* FIXME: Better return code?  Set errno? */
 243           }
 244
 245         memcpy (&sinp->sin6_addr, he->h_addr_list[0], sizeof sinp->sin6_addr);
 246
 247         tmp->ai_addr = (struct sockaddr *) sinp;
 248         tmp->ai_addrlen = sizeof *sinp;
 249       }
 250       break;
 251 #endif
 252
 253 #if HAVE_IPV4
 254     case PF_INET:
 255       {
 256         struct v4_pair *p = storage;
 257         struct sockaddr_in *sinp = &p->sockaddr_in;
 258         tmp = &p->addrinfo;
 259
 260         if (port)
 261           sinp->sin_port = port;
 262
 263         if (he->h_length != sizeof (sinp->sin_addr))
 264           {
 265             free (storage);
 266             return EAI_SYSTEM; /* FIXME: Better return code?  Set errno? */
 267           }
 268
 269         memcpy (&sinp->sin_addr, he->h_addr_list[0], sizeof sinp->sin_addr);
 270
 271         tmp->ai_addr = (struct sockaddr *) sinp;
 272         tmp->ai_addrlen = sizeof *sinp;
 273       }
 274       break;
 275 #endif
 276
 277     default:
 278       free (storage);
 279       return EAI_NODATA;
 280     }
 281
 282   if (hints && hints->ai_flags & AI_CANONNAME)
 283     {
 284       const char *cn;
 285       if (he->h_name)
 286         cn = he->h_name;
 287       else
 288         cn = nodename;
 289
 290       tmp->ai_canonname = strdup (cn);
 291       if (!tmp->ai_canonname)
 292         {
 293           free (storage);
 294           return EAI_MEMORY;
 295         }
 296     }
 297
 298   tmp->ai_protocol = (hints) ? hints->ai_protocol : 0;
 299   tmp->ai_socktype = (hints) ? hints->ai_socktype : 0;
 300   tmp->ai_addr->sa_family = he->h_addrtype;
 301   tmp->ai_family = he->h_addrtype;
 302
 303   /* FIXME: If more than one address, create linked list of addrinfo's. */
 304
 305   *res = tmp;
 306
 307   return 0;
 308 }
 309
 310 /* Free `addrinfo' structure AI including associated storage.  */
 311 void
 312 freeaddrinfo (struct addrinfo *ai)
 313 {
 314 #ifdef WIN32_NATIVE
 315   if (use_win32_p ())
 316     {
 317       freeaddrinfo_ptr (ai);
 318       return;
 319     }
 320 #endif
 321
 322   while (ai)
 323     {
 324       struct addrinfo *cur;
 325
 326       cur = ai;
 327       ai = ai->ai_next;
 328
 329       if (cur->ai_canonname) free (cur->ai_canonname);
 330       free (cur);
 331     }
 332 }
 333
 334 int getnameinfo(const struct sockaddr *restrict sa, socklen_t salen,
 335                 char *restrict node, socklen_t nodelen,
 336                 char *restrict service, socklen_t servicelen,
 337                 int flags)
 338 {
 339 #ifdef WIN32_NATIVE
 340   if (use_win32_p ())
 341     return getnameinfo_ptr (sa, salen, node, nodelen,
 342                             service, servicelen, flags);
 343 #endif
 344
 345   /* FIXME: Support other flags. */
 346   if ((node && nodelen > 0 && !(flags & NI_NUMERICHOST)) ||
 347       (service && servicelen > 0 && !(flags & NI_NUMERICHOST)) ||
 348       (flags & ~(NI_NUMERICHOST|NI_NUMERICSERV)))
 349     return EAI_BADFLAGS;
 350
 351   if (sa == NULL || salen < sizeof (sa->sa_family))
 352     return EAI_FAMILY;
 353
 354   switch (sa->sa_family)
 355     {
 356 #if HAVE_IPV4
 357     case AF_INET:
 358       if (salen < sizeof (struct sockaddr_in))
 359         return EAI_FAMILY;
 360       break;
 361 #endif
 362 #if HAVE_IPV6
 363     case AF_INET6:
 364       if (salen < sizeof (struct sockaddr_in6))
 365         return EAI_FAMILY;
 366       break;
 367 #endif
 368     default:
 369       return EAI_FAMILY;
 370     }
 371
 372   if (node && nodelen > 0 && flags & NI_NUMERICHOST)
 373     {
 374       switch (sa->sa_family)
 375         {
 376 #if HAVE_IPV4
 377         case AF_INET:
 378           if (!inet_ntop (AF_INET,
 379                           &(((const struct sockaddr_in *) sa)->sin_addr),
 380                           node, nodelen))
 381             return EAI_SYSTEM;
 382           break;
 383 #endif
 384
 385 #if HAVE_IPV6
 386         case AF_INET6:
 387           if (!inet_ntop (AF_INET6,
 388                           &(((const struct sockaddr_in6 *) sa)->sin6_addr),
 389                           node, nodelen))
 390             return EAI_SYSTEM;
 391           break;
 392 #endif
 393
 394         default:
 395           return EAI_FAMILY;
 396         }
 397     }
 398
 399   if (service && servicelen > 0 && flags & NI_NUMERICSERV)
 400     switch (sa->sa_family)
 401       {
 402 #if HAVE_IPV4
 403       case AF_INET:
 404 #endif
 405 #if HAVE_IPV6
 406       case AF_INET6:
 407 #endif
 408         {
 409           unsigned short int port
 410             = ntohs (((const struct sockaddr_in *) sa)->sin_port);
 411           if (servicelen <= snprintf (service, servicelen, "%u", port))
 412             return EAI_OVERFLOW;
 413         }
 414         break;
 415       }
 416
 417   return 0;
 418 }