contrib/ldns/compat/fake-rfc2553.c

   1 /* From openssh 4.3p2 filename openbsd-compat/fake-rfc2553.h */
   2 /*
   3  * Copyright (C) 2000-2003 Damien Miller.  All rights reserved.
   4  * Copyright (C) 1999 WIDE Project.  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  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  * 3. Neither the name of the project nor the names of its contributors
  15  *    may be used to endorse or promote products derived from this software
  16  *    without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  28  * SUCH DAMAGE.
  29  */
  30
  31 /*
  32  * Pseudo-implementation of RFC2553 name / address resolution functions
  33  *
  34  * But these functions are not implemented correctly. The minimum subset
  35  * is implemented for ssh use only. For example, this routine assumes
  36  * that ai_family is AF_INET. Don't use it for another purpose.
  37  */
  38
  39 #include <ldns/config.h>
  40 #include <ldns/common.h>
  41 #include <unistd.h>
  42 #include <string.h>
  43 #include <stdio.h>
  44 #include <stdlib.h>
  45 #include "compat/fake-rfc2553.h"
  46
  47 #ifndef HAVE_GETNAMEINFO
  48 int getnameinfo(const struct sockaddr *sa, size_t ATTR_UNUSED(salen), char *host,
  49                 size_t hostlen, char *serv, size_t servlen, int flags)
  50 {
  51         struct sockaddr_in *sin = (struct sockaddr_in *)sa;
  52         struct hostent *hp;
  53         char tmpserv[16];
  54
  55         if (serv != NULL) {
  56                 snprintf(tmpserv, sizeof(tmpserv), "%d", ntohs(sin->sin_port));
  57                 if (strlcpy(serv, tmpserv, servlen) >= servlen)
  58                         return (EAI_MEMORY);
  59         }
  60
  61         if (host != NULL) {
  62                 if (flags & NI_NUMERICHOST) {
  63                         if (strlcpy(host, inet_ntoa(sin->sin_addr),
  64                             hostlen) >= hostlen)
  65                                 return (EAI_MEMORY);
  66                         else
  67                                 return (0);
  68                 } else {
  69                         hp = gethostbyaddr((char *)&sin->sin_addr,
  70                             sizeof(struct in_addr), AF_INET);
  71                         if (hp == NULL)
  72                                 return (EAI_NODATA);
  73
  74                         if (strlcpy(host, hp->h_name, hostlen) >= hostlen)
  75                                 return (EAI_MEMORY);
  76                         else
  77                                 return (0);
  78                 }
  79         }
  80         return (0);
  81 }
  82 #endif /* !HAVE_GETNAMEINFO */
  83
  84 #ifndef HAVE_GAI_STRERROR
  85 #ifdef HAVE_CONST_GAI_STRERROR_PROTO
  86 const char *
  87 #else
  88 char *
  89 #endif
  90 gai_strerror(int err)
  91 {
  92         switch (err) {
  93         case EAI_NODATA:
  94                 return ("no address associated with name");
  95         case EAI_MEMORY:
  96                 return ("memory allocation failure.");
  97         case EAI_NONAME:
  98                 return ("nodename nor servname provided, or not known");
  99         default:
 100                 return ("unknown/invalid error.");
 101         }
 102 }
 103 #endif /* !HAVE_GAI_STRERROR */
 104
 105 #ifndef HAVE_FREEADDRINFO
 106 void
 107 freeaddrinfo(struct addrinfo *ai)
 108 {
 109         struct addrinfo *next;
 110
 111         for(; ai != NULL;) {
 112                 next = ai->ai_next;
 113                 free(ai);
 114                 ai = next;
 115         }
 116 }
 117 #endif /* !HAVE_FREEADDRINFO */
 118
 119 #ifndef HAVE_GETADDRINFO
 120 static struct
 121 addrinfo *malloc_ai(int port, u_long addr, const struct addrinfo *hints)
 122 {
 123         struct addrinfo *ai;
 124
 125         ai = malloc(sizeof(*ai) + sizeof(struct sockaddr_in));
 126         if (ai == NULL)
 127                 return (NULL);
 128
 129         memset(ai, '\0', sizeof(*ai) + sizeof(struct sockaddr_in));
 130
 131         ai->ai_addr = (struct sockaddr *)(ai + 1);
 132         /* XXX -- ssh doesn't use sa_len */
 133         ai->ai_addrlen = sizeof(struct sockaddr_in);
 134         ai->ai_addr->sa_family = ai->ai_family = AF_INET;
 135
 136         ((struct sockaddr_in *)(ai)->ai_addr)->sin_port = port;
 137         ((struct sockaddr_in *)(ai)->ai_addr)->sin_addr.s_addr = addr;
 138
 139         /* XXX: the following is not generally correct, but does what we want */
 140         if (hints->ai_socktype)
 141                 ai->ai_socktype = hints->ai_socktype;
 142         else
 143                 ai->ai_socktype = SOCK_STREAM;
 144
 145         if (hints->ai_protocol)
 146                 ai->ai_protocol = hints->ai_protocol;
 147
 148         return (ai);
 149 }
 150
 151 int
 152 getaddrinfo(const char *hostname, const char *servname,
 153     const struct addrinfo *hints, struct addrinfo **res)
 154 {
 155         struct hostent *hp;
 156         struct servent *sp;
 157         struct in_addr in;
 158         int i;
 159         long int port;
 160         u_long addr;
 161
 162         port = 0;
 163         if (servname != NULL) {
 164                 char *cp;
 165
 166                 port = strtol(servname, &cp, 10);
 167                 if (port > 0 && port <= 65535 && *cp == '\0')
 168                         port = htons(port);
 169                 else if ((sp = getservbyname(servname, NULL)) != NULL)
 170                         port = sp->s_port;
 171                 else
 172                         port = 0;
 173         }
 174
 175         if (hints && hints->ai_flags & AI_PASSIVE) {
 176                 addr = htonl(0x00000000);
 177                 if (hostname && inet_aton(hostname, &in) != 0)
 178                         addr = in.s_addr;
 179                 *res = malloc_ai(port, addr, hints);
 180                 if (*res == NULL)
 181                         return (EAI_MEMORY);
 182                 return (0);
 183         }
 184
 185         if (!hostname) {
 186                 *res = malloc_ai(port, htonl(0x7f000001), hints);
 187                 if (*res == NULL)
 188                         return (EAI_MEMORY);
 189                 return (0);
 190         }
 191
 192         if (inet_aton(hostname, &in)) {
 193                 *res = malloc_ai(port, in.s_addr, hints);
 194                 if (*res == NULL)
 195                         return (EAI_MEMORY);
 196                 return (0);
 197         }
 198
 199         /* Don't try DNS if AI_NUMERICHOST is set */
 200         if (hints && hints->ai_flags & AI_NUMERICHOST)
 201                 return (EAI_NONAME);
 202
 203         hp = gethostbyname(hostname);
 204         if (hp && hp->h_name && hp->h_name[0] && hp->h_addr_list[0]) {
 205                 struct addrinfo *cur, *prev;
 206
 207                 cur = prev = *res = NULL;
 208                 for (i = 0; hp->h_addr_list[i]; i++) {
 209                         struct in_addr *in = (struct in_addr *)hp->h_addr_list[i];
 210
 211                         cur = malloc_ai(port, in->s_addr, hints);
 212                         if (cur == NULL) {
 213                                 if (*res != NULL)
 214                                         freeaddrinfo(*res);
 215                                 return (EAI_MEMORY);
 216                         }
 217                         if (prev)
 218                                 prev->ai_next = cur;
 219                         else
 220                                 *res = cur;
 221
 222                         prev = cur;
 223                 }
 224                 return (0);
 225         }
 226
 227         return (EAI_NODATA);
 228 }
 229 #endif /* !HAVE_GETADDRINFO */