lib/roken/getnameinfo.c

   1 /*
   2  * Copyright (c) 1999 - 2001 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #ifdef HAVE_CONFIG_H
  35 #include <config.h>
  36 RCSID("$Id$");
  37 #endif
  38
  39 #include "roken.h"
  40
  41 static int
  42 doit (int af,
  43       const void *addr,
  44       size_t addrlen,
  45       int port,
  46       char *host, size_t hostlen,
  47       char *serv, size_t servlen,
  48       int flags)
  49 {
  50     if (host != NULL) {
  51         if (flags & NI_NUMERICHOST) {
  52             if (inet_ntop (af, addr, host, hostlen) == NULL)
  53                 return EAI_SYSTEM;
  54         } else {
  55             struct hostent *he = gethostbyaddr (addr,
  56                                                 addrlen,
  57                                                 af);
  58             if (he != NULL) {
  59                 strlcpy (host, hostent_find_fqdn(he), hostlen);
  60                 if (flags & NI_NOFQDN) {
  61                     char *dot = strchr (host, '.');
  62                     if (dot != NULL)
  63                         *dot = '\0';
  64                 }
  65             } else if (flags & NI_NAMEREQD) {
  66                 return EAI_NONAME;
  67             } else if (inet_ntop (af, addr, host, hostlen) == NULL)
  68                 return EAI_SYSTEM;
  69         }
  70     }
  71
  72     if (serv != NULL) {
  73         if (flags & NI_NUMERICSERV) {
  74             snprintf (serv, servlen, "%u", ntohs(port));
  75         } else {
  76             const char *proto = "tcp";
  77             struct servent *se;
  78
  79             if (flags & NI_DGRAM)
  80                 proto = "udp";
  81
  82             se = getservbyport (port, proto);
  83             if (se == NULL) {
  84                 snprintf (serv, servlen, "%u", ntohs(port));
  85             } else {
  86                 strlcpy (serv, se->s_name, servlen);
  87             }
  88         }
  89     }
  90     return 0;
  91 }
  92
  93 /*
  94  *
  95  */
  96
  97 int ROKEN_LIB_FUNCTION
  98 getnameinfo(const struct sockaddr *sa, socklen_t salen,
  99             char *host, size_t hostlen,
 100             char *serv, size_t servlen,
 101             int flags)
 102 {
 103     switch (sa->sa_family) {
 104 #ifdef HAVE_IPV6
 105     case AF_INET6 : {
 106         const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)sa;
 107
 108         return doit (AF_INET6, &sin6->sin6_addr, sizeof(sin6->sin6_addr),
 109                      sin6->sin6_port,
 110                      host, hostlen,
 111                      serv, servlen,
 112                      flags);
 113     }
 114 #endif
 115     case AF_INET : {
 116         const struct sockaddr_in *sin4 = (const struct sockaddr_in *)sa;
 117
 118         return doit (AF_INET, &sin4->sin_addr, sizeof(sin4->sin_addr),
 119                      sin4->sin_port,
 120                      host, hostlen,
 121                      serv, servlen,
 122                      flags);
 123     }
 124     default :
 125         return EAI_FAMILY;
 126     }
 127 }