Modules/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 #if 0
  38 #include <sys/types.h>
  39 #include <sys/socket.h>
  40 #include <netinet/in.h>
  41 #include <arpa/inet.h>
  42 #include <arpa/nameser.h>
  43 #include <netdb.h>
  44 #include <resolv.h>
  45 #include <string.h>
  46 #include <stddef.h>
  47
  48 #include "addrinfo.h"
  49 #endif
  50
  51 #define SUCCESS 0
  52 #define YES 1
  53 #define NO  0
  54
  55 static struct gni_afd {
  56         int a_af;
  57         int a_addrlen;
  58         int a_socklen;
  59         int a_off;
  60 } gni_afdl [] = {
  61 #ifdef ENABLE_IPV6
  62         {PF_INET6, sizeof(struct in6_addr), sizeof(struct sockaddr_in6),
  63                 offsetof(struct sockaddr_in6, sin6_addr)},
  64 #endif
  65         {PF_INET, sizeof(struct in_addr), sizeof(struct sockaddr_in),
  66                 offsetof(struct sockaddr_in, sin_addr)},
  67         {0, 0, 0},
  68 };
  69
  70 struct gni_sockinet {
  71         u_char  si_len;
  72         u_char  si_family;
  73         u_short si_port;
  74 };
  75
  76 #define ENI_NOSOCKET    0
  77 #define ENI_NOSERVNAME  1
  78 #define ENI_NOHOSTNAME  2
  79 #define ENI_MEMORY      3
  80 #define ENI_SYSTEM      4
  81 #define ENI_FAMILY      5
  82 #define ENI_SALEN       6
  83
  84 /* forward declaration to make gcc happy */
  85 int getnameinfo Py_PROTO((const struct sockaddr *, size_t, char *, size_t,
  86                           char *, size_t, int));
  87
  88 int
  89 getnameinfo(sa, salen, host, hostlen, serv, servlen, flags)
  90         const struct sockaddr *sa;
  91         size_t salen;
  92         char *host;
  93         size_t hostlen;
  94         char *serv;
  95         size_t servlen;
  96         int flags;
  97 {
  98         struct gni_afd *gni_afd;
  99         struct servent *sp;
 100         struct hostent *hp;
 101         u_short port;
 102         int family, len, i;
 103         char *addr, *p;
 104         u_long v4a;
 105 #ifdef ENABLE_IPV6
 106         u_char pfx;
 107 #endif
 108         int h_error;
 109         char numserv[512];
 110         char numaddr[512];
 111
 112         if (sa == NULL)
 113                 return ENI_NOSOCKET;
 114
 115 #ifdef HAVE_SOCKADDR_SA_LEN
 116         len = sa->sa_len;
 117         if (len != salen) return ENI_SALEN;
 118 #else
 119         len = salen;
 120 #endif
 121
 122         family = sa->sa_family;
 123         for (i = 0; gni_afdl[i].a_af; i++)
 124                 if (gni_afdl[i].a_af == family) {
 125                         gni_afd = &gni_afdl[i];
 126                         goto found;
 127                 }
 128         return ENI_FAMILY;
 129
 130  found:
 131         if (len != gni_afd->a_socklen) return ENI_SALEN;
 132
 133         port = ((struct gni_sockinet *)sa)->si_port; /* network byte order */
 134         addr = (char *)sa + gni_afd->a_off;
 135
 136         if (serv == NULL || servlen == 0) {
 137                 /* what we should do? */
 138         } else if (flags & NI_NUMERICSERV) {
 139                 sprintf(numserv, "%d", ntohs(port));
 140                 if (strlen(numserv) > servlen)
 141                         return ENI_MEMORY;
 142                 strcpy(serv, numserv);
 143         } else {
 144                 sp = getservbyport(port, (flags & NI_DGRAM) ? "udp" : "tcp");
 145                 if (sp) {
 146                         if (strlen(sp->s_name) > servlen)
 147                                 return ENI_MEMORY;
 148                         strcpy(serv, sp->s_name);
 149                 } else
 150                         return ENI_NOSERVNAME;
 151         }
 152
 153         switch (sa->sa_family) {
 154         case AF_INET:
 155                 v4a = ((struct sockaddr_in *)sa)->sin_addr.s_addr;
 156                 if (IN_MULTICAST(v4a) || IN_EXPERIMENTAL(v4a))
 157                         flags |= NI_NUMERICHOST;
 158                 v4a >>= IN_CLASSA_NSHIFT;
 159                 if (v4a == 0 || v4a == IN_LOOPBACKNET)
 160                         flags |= NI_NUMERICHOST;
 161                 break;
 162 #ifdef ENABLE_IPV6
 163         case AF_INET6:
 164                 pfx = ((struct sockaddr_in6 *)sa)->sin6_addr.s6_addr8[0];
 165                 if (pfx == 0 || pfx == 0xfe || pfx == 0xff)
 166                         flags |= NI_NUMERICHOST;
 167                 break;
 168 #endif
 169         }
 170         if (host == NULL || hostlen == 0) {
 171                 /* what should we do? */
 172         } else if (flags & NI_NUMERICHOST) {
 173                 if (inet_ntop(gni_afd->a_af, addr, numaddr, sizeof(numaddr))
 174                     == NULL)
 175                         return ENI_SYSTEM;
 176                 if (strlen(numaddr) > hostlen)
 177                         return ENI_MEMORY;
 178                 strcpy(host, numaddr);
 179         } else {
 180 #ifdef ENABLE_IPV6
 181                 hp = getipnodebyaddr(addr, gni_afd->a_addrlen, gni_afd->a_af, &h_error);
 182 #else
 183                 hp = gethostbyaddr(addr, gni_afd->a_addrlen, gni_afd->a_af);
 184                 h_error = h_errno;
 185 #endif
 186
 187                 if (hp) {
 188                         if (flags & NI_NOFQDN) {
 189                                 p = strchr(hp->h_name, '.');
 190                                 if (p) *p = '\0';
 191                         }
 192                         if (strlen(hp->h_name) > hostlen) {
 193 #ifdef ENABLE_IPV6
 194                                 freehostent(hp);
 195 #endif
 196                                 return ENI_MEMORY;
 197                         }
 198                         strcpy(host, hp->h_name);
 199 #ifdef ENABLE_IPV6
 200                         freehostent(hp);
 201 #endif
 202                 } else {
 203                         if (flags & NI_NAMEREQD)
 204                                 return ENI_NOHOSTNAME;
 205                         if (inet_ntop(gni_afd->a_af, addr, numaddr, sizeof(numaddr))
 206                             == NULL)
 207                                 return ENI_NOHOSTNAME;
 208                         if (strlen(numaddr) > hostlen)
 209                                 return ENI_MEMORY;
 210                         strcpy(host, numaddr);
 211                 }
 212         }
 213         return SUCCESS;
 214 }