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 #include <config.h>
  35
  36 #include "roken.h"
  37
  38 static int
  39 doit (int af,
  40       const void *addr,
  41       size_t addrlen,
  42       int port,
  43       char *host, size_t hostlen,
  44       char *serv, size_t servlen,
  45       int flags)
  46 {
  47     if (host != NULL) {
  48         if (flags & NI_NUMERICHOST) {
  49             if (inet_ntop (af, addr, host, hostlen) == NULL)
  50                 return EAI_SYSTEM;
  51         } else {
  52             struct hostent *he = gethostbyaddr (addr,
  53                                                 addrlen,
  54                                                 af);
  55             if (he != NULL) {
  56                 strlcpy (host, hostent_find_fqdn(he), hostlen);
  57                 if (flags & NI_NOFQDN) {
  58                     char *dot = strchr (host, '.');
  59                     if (dot != NULL)
  60                         *dot = '\0';
  61                 }
  62             } else if (flags & NI_NAMEREQD) {
  63                 return EAI_NONAME;
  64             } else if (inet_ntop (af, addr, host, hostlen) == NULL)
  65                 return EAI_SYSTEM;
  66         }
  67     }
  68
  69     if (serv != NULL) {
  70         if (flags & NI_NUMERICSERV) {
  71             snprintf (serv, servlen, "%u", ntohs(port));
  72         } else {
  73             const char *proto = "tcp";
  74             struct servent *se;
  75
  76             if (flags & NI_DGRAM)
  77                 proto = "udp";
  78
  79             se = getservbyport (port, proto);
  80             if (se == NULL) {
  81                 snprintf (serv, servlen, "%u", ntohs(port));
  82             } else {
  83                 strlcpy (serv, se->s_name, servlen);
  84             }
  85         }
  86     }
  87     return 0;
  88 }
  89
  90 /*
  91  *
  92  */
  93
  94 ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
  95 getnameinfo(const struct sockaddr *sa, socklen_t salen,
  96             char *host, size_t hostlen,
  97             char *serv, size_t servlen,
  98             int flags)
  99 {
 100     switch (sa->sa_family) {
 101 #ifdef HAVE_IPV6
 102     case AF_INET6 : {
 103         const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)sa;
 104
 105         return doit (AF_INET6, &sin6->sin6_addr, sizeof(sin6->sin6_addr),
 106                      sin6->sin6_port,
 107                      host, hostlen,
 108                      serv, servlen,
 109                      flags);
 110     }
 111 #endif
 112     case AF_INET : {
 113         const struct sockaddr_in *sin4 = (const struct sockaddr_in *)sa;
 114
 115         return doit (AF_INET, &sin4->sin_addr, sizeof(sin4->sin_addr),
 116                      sin4->sin_port,
 117                      host, hostlen,
 118                      serv, servlen,
 119                      flags);
 120     }
 121     default :
 122         return EAI_FAMILY;
 123     }
 124 }