openbsd-compat/fake-rfc2553.c

   1 /*
   2  * Copyright (C) 2000-2003 Damien Miller.  All rights reserved.
   3  * Copyright (C) 1999 WIDE Project.  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  * Pseudo-implementation of RFC2553 name / address resolution functions
  32  *
  33  * But these functions are not implemented correctly. The minimum subset
  34  * is implemented for ssh use only. For example, this routine assumes
  35  * that ai_family is AF_INET. Don't use it for another purpose.
  36  */
  37
  38 #include "includes.h"
  39
  40 RCSID("$Id: fake-rfc2553.c,v 1.5 2003/09/22 02:08:23 dtucker Exp $");
  41
  42 #ifndef HAVE_GETNAMEINFO
  43 int getnameinfo(const struct sockaddr *sa, size_t salen, char *host,
  44                 size_t hostlen, char *serv, size_t servlen, int flags)
  45 {
  46         struct sockaddr_in *sin = (struct sockaddr_in *)sa;
  47         struct hostent *hp;
  48         char tmpserv[16];
  49
  50         if (serv != NULL) {
  51                 snprintf(tmpserv, sizeof(tmpserv), "%d", ntohs(sin->sin_port));
  52                 if (strlcpy(serv, tmpserv, servlen) >= servlen)
  53                         return (EAI_MEMORY);
  54         }
  55
  56         if (host != NULL) {
  57                 if (flags & NI_NUMERICHOST) {
  58                         if (strlcpy(host, inet_ntoa(sin->sin_addr),
  59                             hostlen) >= hostlen)
  60                                 return (EAI_MEMORY);
  61                         else
  62                                 return (0);
  63                 } else {
  64                         hp = gethostbyaddr((char *)&sin->sin_addr,
  65                             sizeof(struct in_addr), AF_INET);
  66                         if (hp == NULL)
  67                                 return (EAI_NODATA);
  68
  69                         if (strlcpy(host, hp->h_name, hostlen) >= hostlen)
  70                                 return (EAI_MEMORY);
  71                         else
  72                                 return (0);
  73                 }
  74         }
  75         return (0);
  76 }
  77 #endif /* !HAVE_GETNAMEINFO */
  78
  79 #ifndef HAVE_GAI_STRERROR
  80 #ifdef HAVE_CONST_GAI_STRERROR_PROTO
  81 const char *
  82 #else
  83 char *
  84 #endif
  85 gai_strerror(int err)
  86 {
  87         switch (err) {
  88         case EAI_NODATA:
  89                 return ("no address associated with name");
  90         case EAI_MEMORY:
  91                 return ("memory allocation failure.");
  92         case EAI_NONAME:
  93                 return ("nodename nor servname provided, or not known");
  94         default:
  95                 return ("unknown/invalid error.");
  96         }
  97 }
  98 #endif /* !HAVE_GAI_STRERROR */
  99
 100 #ifndef HAVE_FREEADDRINFO
 101 void
 102 freeaddrinfo(struct addrinfo *ai)
 103 {
 104         struct addrinfo *next;
 105
 106         for(; ai != NULL;) {
 107                 next = ai->ai_next;
 108                 free(ai);
 109                 ai = next;
 110         }
 111 }
 112 #endif /* !HAVE_FREEADDRINFO */
 113
 114 #ifndef HAVE_GETADDRINFO
 115 static struct
 116 addrinfo *malloc_ai(int port, u_long addr, const struct addrinfo *hints)
 117 {
 118         struct addrinfo *ai;
 119
 120         ai = malloc(sizeof(*ai) + sizeof(struct sockaddr_in));
 121         if (ai == NULL)
 122                 return (NULL);
 123
 124         memset(ai, '\0', sizeof(*ai) + sizeof(struct sockaddr_in));
 125
 126         ai->ai_addr = (struct sockaddr *)(ai + 1);
 127         /* XXX -- ssh doesn't use sa_len */
 128         ai->ai_addrlen = sizeof(struct sockaddr_in);
 129         ai->ai_addr->sa_family = ai->ai_family = AF_INET;
 130
 131         ((struct sockaddr_in *)(ai)->ai_addr)->sin_port = port;
 132         ((struct sockaddr_in *)(ai)->ai_addr)->sin_addr.s_addr = addr;
 133
 134         /* XXX: the following is not generally correct, but does what we want */
 135         if (hints->ai_socktype)
 136                 ai->ai_socktype = hints->ai_socktype;
 137         else
 138                 ai->ai_socktype = SOCK_STREAM;
 139
 140         if (hints->ai_protocol)
 141                 ai->ai_protocol = hints->ai_protocol;
 142
 143         return (ai);
 144 }
 145
 146 int
 147 getaddrinfo(const char *hostname, const char *servname,
 148     const struct addrinfo *hints, struct addrinfo **res)
 149 {
 150         struct hostent *hp;
 151         struct servent *sp;
 152         struct in_addr in;
 153         int i;
 154         long int port;
 155         u_long addr;
 156
 157         port = 0;
 158         if (servname != NULL) {
 159                 char *cp;
 160
 161                 port = strtol(servname, &cp, 10);
 162                 if (port > 0 && port <= 65535 && *cp == '\0')
 163                         port = htons(port);
 164                 else if ((sp = getservbyname(servname, NULL)) != NULL)
 165                         port = sp->s_port;
 166                 else
 167                         port = 0;
 168         }
 169
 170         if (hints && hints->ai_flags & AI_PASSIVE) {
 171                 addr = htonl(0x00000000);
 172                 if (hostname && inet_aton(hostname, &in) != 0)
 173                         addr = in.s_addr;
 174                 *res = malloc_ai(port, addr, hints);
 175                 if (*res == NULL)
 176                         return (EAI_MEMORY);
 177                 return (0);
 178         }
 179
 180         if (!hostname) {
 181                 *res = malloc_ai(port, htonl(0x7f000001), hints);
 182                 if (*res == NULL)
 183                         return (EAI_MEMORY);
 184                 return (0);
 185         }
 186
 187         if (inet_aton(hostname, &in)) {
 188                 *res = malloc_ai(port, in.s_addr, hints);
 189                 if (*res == NULL)
 190                         return (EAI_MEMORY);
 191                 return (0);
 192         }
 193
 194         /* Don't try DNS if AI_NUMERICHOST is set */
 195         if (hints && hints->ai_flags & AI_NUMERICHOST)
 196                 return (EAI_NONAME);
 197
 198         hp = gethostbyname(hostname);
 199         if (hp && hp->h_name && hp->h_name[0] && hp->h_addr_list[0]) {
 200                 struct addrinfo *cur, *prev;
 201
 202                 cur = prev = *res = NULL;
 203                 for (i = 0; hp->h_addr_list[i]; i++) {
 204                         struct in_addr *in = (struct in_addr *)hp->h_addr_list[i];
 205
 206                         cur = malloc_ai(port, in->s_addr, hints);
 207                         if (cur == NULL) {
 208                                 if (*res != NULL)
 209                                         freeaddrinfo(*res);
 210                                 return (EAI_MEMORY);
 211                         }
 212                         if (prev)
 213                                 prev->ai_next = cur;
 214                         else
 215                                 *res = cur;
 216
 217                         prev = cur;
 218                 }
 219                 return (0);
 220         }
 221
 222         return (EAI_NODATA);
 223 }
 224 #endif /* !HAVE_GETADDRINFO */