gl/getaddrinfo.c

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