stdlib/ext/socket/getnameinfo.c

   1 /*
   2  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the project nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 /*
  31  * Issues to be discussed:
  32  * - Thread safe-ness must be checked
  33  * - Return values.  There seems to be no standard for return value (RFC2133)
  34  *   but INRIA implementation returns EAI_xxx defined for getaddrinfo().
  35  */
  36
  37 #include "config.h"
  38 #include <sys/types.h>
  39 #ifndef _WIN32
  40 #if defined(__BEOS__)
  41 # include <net/socket.h>
  42 #else
  43 # include <sys/socket.h>
  44 #endif
  45 #include <netinet/in.h>
  46 #if defined(HAVE_ARPA_INET_H)
  47 #include <arpa/inet.h>
  48 #endif
  49 #if defined(HAVE_ARPA_NAMESER_H)
  50 #include <arpa/nameser.h>
  51 #endif
  52 #include <netdb.h>
  53 #if defined(HAVE_RESOLV_H)
  54 #ifdef _SX
  55 #include <stdio.h>
  56 #endif
  57 #include <resolv.h>
  58 #endif
  59 #endif
  60 #ifdef _WIN32
  61 #include <winsock2.h>
  62 #include <stdio.h>
  63 #define snprintf _snprintf
  64 #endif
  65
  66 #include <string.h>
  67 #include <stddef.h>
  68
  69 #ifdef SOCKS5
  70 #include <socks.h>
  71 #endif
  72
  73 #include "addrinfo.h"
  74 #include "sockport.h"
  75
  76 #define SUCCESS 0
  77 #define ANY 0
  78 #define YES 1
  79 #define NO  0
  80
  81 struct sockinet {
  82         u_char  si_len;
  83         u_char  si_family;
  84         u_short si_port;
  85 };
  86
  87 static struct afd {
  88         int a_af;
  89         int a_addrlen;
  90         int a_socklen;
  91         int a_off;
  92 } afdl [] = {
  93 #ifdef INET6
  94 #define N_INET6 0
  95         {PF_INET6, sizeof(struct in6_addr),
  96          sizeof(struct sockaddr_in6),
  97          offsetof(struct sockaddr_in6, sin6_addr)},
  98 #define N_INET  1
  99 #else
 100 #define N_INET  0
 101 #endif
 102         {PF_INET, sizeof(struct in_addr),
 103          sizeof(struct sockaddr_in),
 104          offsetof(struct sockaddr_in, sin_addr)},
 105         {0, 0, 0, 0},
 106 };
 107
 108 #define ENI_NOSOCKET    0
 109 #define ENI_NOSERVNAME  1
 110 #define ENI_NOHOSTNAME  2
 111 #define ENI_MEMORY      3
 112 #define ENI_SYSTEM      4
 113 #define ENI_FAMILY      5
 114 #define ENI_SALEN       6
 115
 116 #ifndef HAVE_INET_NTOP
 117 static const char *
 118 inet_ntop(af, addr, numaddr, numaddr_len)
 119         int af;
 120         const void *addr;
 121         char *numaddr;
 122         size_t numaddr_len;
 123 {
 124 #ifdef HAVE_INET_NTOA
 125         struct in_addr in;
 126         memcpy(&in.s_addr, addr, sizeof(in.s_addr));
 127         snprintf(numaddr, numaddr_len, "%s", inet_ntoa(in));
 128 #else
 129         unsigned long x = ntohl(*(unsigned long*)addr);
 130         snprintf(numaddr, numaddr_len, "%d.%d.%d.%d",
 131                  (int) (x>>24) & 0xff, (int) (x>>16) & 0xff,
 132                  (int) (x>> 8) & 0xff, (int) (x>> 0) & 0xff);
 133 #endif
 134         return numaddr;
 135 }
 136 #endif
 137
 138 int
 139 getnameinfo(sa, salen, host, hostlen, serv, servlen, flags)
 140         const struct sockaddr *sa;
 141         size_t salen;
 142         char *host;
 143         size_t hostlen;
 144         char *serv;
 145         size_t servlen;
 146         int flags;
 147 {
 148         struct afd *afd;
 149         struct servent *sp;
 150         struct hostent *hp;
 151         u_short port;
 152         int family, len, i;
 153         char *addr, *p;
 154         u_long v4a;
 155 #ifdef INET6
 156         u_char pfx;
 157 #endif
 158         int h_error;
 159         char numserv[512];
 160         char numaddr[512];
 161
 162         if (sa == NULL)
 163                 return ENI_NOSOCKET;
 164
 165         len = SA_LEN(sa);
 166         if (len != salen) return ENI_SALEN;
 167
 168         family = sa->sa_family;
 169         for (i = 0; afdl[i].a_af; i++)
 170                 if (afdl[i].a_af == family) {
 171                         afd = &afdl[i];
 172                         goto found;
 173                 }
 174         return ENI_FAMILY;
 175
 176  found:
 177         if (len != afd->a_socklen) return ENI_SALEN;
 178
 179         port = ((struct sockinet *)sa)->si_port; /* network byte order */
 180         addr = (char *)sa + afd->a_off;
 181
 182         if (serv == NULL || servlen == 0) {
 183                 /* what we should do? */
 184         } else if (flags & NI_NUMERICSERV) {
 185                 snprintf(numserv, sizeof(numserv), "%d", ntohs(port));
 186                 if (strlen(numserv) + 1 > servlen)
 187                         return ENI_MEMORY;
 188                 strcpy(serv, numserv);
 189         } else {
 190 #if defined(HAVE_GETSERVBYPORT)
 191                 sp = getservbyport(port, (flags & NI_DGRAM) ? "udp" : "tcp");
 192                 if (sp) {
 193                         if (strlen(sp->s_name) + 1 > servlen)
 194                                 return ENI_MEMORY;
 195                         strcpy(serv, sp->s_name);
 196                 } else
 197                         return ENI_NOSERVNAME;
 198 #else
 199                 return ENI_NOSERVNAME;
 200 #endif
 201         }
 202
 203         switch (sa->sa_family) {
 204         case AF_INET:
 205                 v4a = ntohl(((struct sockaddr_in *)sa)->sin_addr.s_addr);
 206                 if (IN_MULTICAST(v4a) || IN_EXPERIMENTAL(v4a))
 207                         flags |= NI_NUMERICHOST;
 208                 v4a >>= IN_CLASSA_NSHIFT;
 209                 if (v4a == 0)
 210                         flags |= NI_NUMERICHOST;
 211                 break;
 212 #ifdef INET6
 213         case AF_INET6:
 214 #ifdef HAVE_ADDR8
 215                 pfx = ((struct sockaddr_in6 *)sa)->sin6_addr.s6_addr8[0];
 216 #else
 217                 pfx = ((struct sockaddr_in6 *)sa)->sin6_addr.s6_addr[0];
 218 #endif
 219                 if (pfx == 0 || pfx == 0xfe || pfx == 0xff)
 220                         flags |= NI_NUMERICHOST;
 221                 break;
 222 #endif
 223         }
 224         if (host == NULL || hostlen == 0) {
 225                 /* what should we do? */
 226         } else if (flags & NI_NUMERICHOST) {
 227                 if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr))
 228                     == NULL)
 229                         return ENI_SYSTEM;
 230                 if (strlen(numaddr) > hostlen)
 231                         return ENI_MEMORY;
 232                 strcpy(host, numaddr);
 233         } else {
 234 #ifdef INET6
 235                 hp = getipnodebyaddr(addr, afd->a_addrlen, afd->a_af, &h_error);
 236 #else
 237                 hp = gethostbyaddr(addr, afd->a_addrlen, afd->a_af);
 238                 h_error = h_errno;
 239 #endif
 240
 241                 if (hp) {
 242                         if (flags & NI_NOFQDN) {
 243                                 p = strchr(hp->h_name, '.');
 244                                 if (p) *p = '\0';
 245                         }
 246                         if (strlen(hp->h_name) + 1 > hostlen) {
 247 #ifdef INET6
 248                                 freehostent(hp);
 249 #endif
 250                                 return ENI_MEMORY;
 251                         }
 252                         strcpy(host, hp->h_name);
 253 #ifdef INET6
 254                         freehostent(hp);
 255 #endif
 256                 } else {
 257                         if (flags & NI_NAMEREQD)
 258                                 return ENI_NOHOSTNAME;
 259                         if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr))
 260                             == NULL)
 261                                 return ENI_NOHOSTNAME;
 262                         if (strlen(numaddr) > hostlen)
 263                                 return ENI_MEMORY;
 264                         strcpy(host, numaddr);
 265                 }
 266         }
 267         return SUCCESS;
 268 }