1 /*- 2 * Copyright (c) 1994, Garrett Wollman 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS ``AS IS'' AND 14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23 * SUCH DAMAGE. 24 * 25 * $FreeBSD: src/lib/libc/net/gethostnamadr.c,v 1.15.2.2 2001/03/05 10:40:42 obrien Exp $ 26 * $DragonFly: src/lib/libc/net/gethostnamadr.c,v 1.6 2007/12/29 22:55:29 matthias Exp $ 27 */ 28 29 #include <sys/param.h> 30 #include <sys/socket.h> 31 #include <netinet/in.h> 32 #include <arpa/inet.h> 33 #include <netdb.h> 34 #include <stdio.h> 35 #include <ctype.h> 36 #include <string.h> 37 #include <arpa/nameser.h> /* XXX hack for _res */ 38 #include <resolv.h> /* XXX hack for _res */ 39 40 #define _PATH_HOSTCONF "/etc/host.conf" 41 42 enum service_type { 43 SERVICE_NONE = 0, 44 SERVICE_BIND, 45 SERVICE_HOSTS, 46 SERVICE_NIS }; 47 #define SERVICE_MAX SERVICE_NIS 48 49 static struct { 50 const char *name; 51 enum service_type type; 52 } service_names[] = { 53 { "hosts", SERVICE_HOSTS }, 54 { "/etc/hosts", SERVICE_HOSTS }, 55 { "hosttable", SERVICE_HOSTS }, 56 { "htable", SERVICE_HOSTS }, 57 { "bind", SERVICE_BIND }, 58 { "dns", SERVICE_BIND }, 59 { "domain", SERVICE_BIND }, 60 { "yp", SERVICE_NIS }, 61 { "yellowpages", SERVICE_NIS }, 62 { "nis", SERVICE_NIS }, 63 { 0, SERVICE_NONE } 64 }; 65 66 static enum service_type service_order[SERVICE_MAX + 1]; 67 static int service_done = 0; 68 69 static enum service_type 70 get_service_name(const char *name) { 71 int i; 72 for(i = 0; service_names[i].type != SERVICE_NONE; i++) { 73 if(!strcasecmp(name, service_names[i].name)) { 74 return service_names[i].type; 75 } 76 } 77 return SERVICE_NONE; 78 } 79 80 static void 81 init_services(void) 82 { 83 char *cp, *p, buf[BUFSIZ]; 84 int cc = 0; 85 FILE *fd; 86 87 if ((fd = (FILE *)fopen(_PATH_HOSTCONF, "r")) == NULL) { 88 /* make some assumptions */ 89 service_order[0] = SERVICE_BIND; 90 service_order[1] = SERVICE_HOSTS; 91 service_order[2] = SERVICE_NONE; 92 } else { 93 while (fgets(buf, BUFSIZ, fd) != NULL && cc < SERVICE_MAX) { 94 if(buf[0] == '#') 95 continue; 96 97 p = buf; 98 while ((cp = strsep(&p, "\n \t,:;")) != NULL && *cp == '\0') 99 ; 100 if (cp == NULL) 101 continue; 102 do { 103 if (isalpha((unsigned char)cp[0])) { 104 service_order[cc] = get_service_name(cp); 105 if(service_order[cc] != SERVICE_NONE) 106 cc++; 107 } 108 while ((cp = strsep(&p, "\n \t,:;")) != NULL && *cp == '\0') 109 ; 110 } while(cp != NULL && cc < SERVICE_MAX); 111 } 112 service_order[cc] = SERVICE_NONE; 113 fclose(fd); 114 } 115 service_done = 1; 116 } 117 118 struct hostent * 119 gethostbyname(const char *name) 120 { 121 struct hostent *hp; 122 123 if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 124 h_errno = NETDB_INTERNAL; 125 return (NULL); 126 } 127 if (_res.options & RES_USE_INET6) { /* XXX */ 128 hp = gethostbyname2(name, AF_INET6); /* XXX */ 129 if (hp) /* XXX */ 130 return (hp); /* XXX */ 131 } /* XXX */ 132 return (gethostbyname2(name, AF_INET)); 133 } 134 135 struct hostent * 136 gethostbyname2(const char *name, int type) 137 { 138 struct hostent *hp = 0; 139 int nserv = 0; 140 141 if (!service_done) 142 init_services(); 143 144 while (!hp) { 145 switch (service_order[nserv]) { 146 case SERVICE_NONE: 147 return NULL; 148 case SERVICE_HOSTS: 149 hp = _gethostbyhtname(name, type); 150 break; 151 case SERVICE_BIND: 152 hp = _gethostbydnsname(name, type); 153 break; 154 case SERVICE_NIS: 155 hp = _gethostbynisname(name, type); 156 break; 157 } 158 nserv++; 159 } 160 return hp; 161 } 162 163 struct hostent * 164 gethostbyaddr(const char *addr, int len, int type) 165 { 166 struct hostent *hp = 0; 167 int nserv = 0; 168 169 if (!service_done) 170 init_services(); 171 172 while (!hp) { 173 switch (service_order[nserv]) { 174 case SERVICE_NONE: 175 return 0; 176 case SERVICE_HOSTS: 177 hp = _gethostbyhtaddr(addr, len, type); 178 break; 179 case SERVICE_BIND: 180 hp = _gethostbydnsaddr(addr, len, type); 181 break; 182 case SERVICE_NIS: 183 hp = _gethostbynisaddr(addr, len, type); 184 break; 185 } 186 nserv++; 187 } 188 return hp; 189 } 190 191 void 192 sethostent(int stayopen) 193 { 194 _sethosthtent(stayopen); 195 _sethostdnsent(stayopen); 196 } 197 198 void 199 endhostent(void) 200 { 201 _endhosthtent(); 202 _endhostdnsent(); 203 } 204