getnameinfo.c revision 1.4.4.1
1 /* $NetBSD: getnameinfo.c,v 1.4.4.1 1999/12/27 18:29:42 wrstuden Exp $ */ 2 3 /* 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /* 33 * Issues to be discussed: 34 * - Thread safe-ness must be checked 35 * - Return values. There seems to be no standard for return value (RFC2553) 36 * but INRIA implementation returns EAI_xxx defined for getaddrinfo(). 37 * - RFC2553 says that we should raise error on short buffer. X/Open says 38 * we need to truncate the result. We obey RFC2553 (and X/Open should be 39 * modified). 40 */ 41 42 #if 0 43 #ifdef HAVE_CONFIG_H 44 #include "config.h" 45 #endif 46 #else 47 #define HAVE_SA_LEN 48 #endif 49 50 #include <sys/types.h> 51 #include <sys/socket.h> 52 #include <net/if.h> 53 #include <netinet/in.h> 54 #include <arpa/inet.h> 55 #include <arpa/nameser.h> 56 #include <netdb.h> 57 #include <resolv.h> 58 #include <string.h> 59 #include <stddef.h> 60 61 #if 0 62 #ifndef HAVE_PORTABLE_PROTOTYPE 63 #include "cdecl_ext.h" 64 #endif 65 66 #ifndef HAVE_ADDRINFO 67 #include "addrinfo.h" 68 #endif 69 #endif 70 71 #define SUCCESS 0 72 #define ANY 0 73 #define YES 1 74 #define NO 0 75 76 static struct afd { 77 int a_af; 78 int a_addrlen; 79 int a_socklen; 80 int a_off; 81 } afdl [] = { 82 #ifdef INET6 83 {PF_INET6, sizeof(struct in6_addr), sizeof(struct sockaddr_in6), 84 offsetof(struct sockaddr_in6, sin6_addr)}, 85 #endif 86 {PF_INET, sizeof(struct in_addr), sizeof(struct sockaddr_in), 87 offsetof(struct sockaddr_in, sin_addr)}, 88 {0, 0, 0}, 89 }; 90 91 struct sockinet { 92 u_char si_len; 93 u_char si_family; 94 u_short si_port; 95 }; 96 97 #define ENI_NOSOCKET 0 98 #define ENI_NOSERVNAME 1 99 #define ENI_NOHOSTNAME 2 100 #define ENI_MEMORY 3 101 #define ENI_SYSTEM 4 102 #define ENI_FAMILY 5 103 #define ENI_SALEN 6 104 105 int 106 getnameinfo(sa, salen, host, hostlen, serv, servlen, flags) 107 const struct sockaddr *sa; 108 size_t salen; 109 char *host; 110 size_t hostlen; 111 char *serv; 112 size_t servlen; 113 int flags; 114 { 115 struct afd *afd; 116 struct servent *sp; 117 struct hostent *hp; 118 u_short port; 119 int family, i; 120 char *addr, *p; 121 u_int32_t v4a; 122 int h_error; 123 char numserv[512]; 124 char numaddr[512]; 125 126 if (sa == NULL) 127 return ENI_NOSOCKET; 128 129 #ifdef HAVE_SA_LEN 130 if (sa->sa_len != salen) 131 return ENI_SALEN; 132 #endif 133 134 family = sa->sa_family; 135 for (i = 0; afdl[i].a_af; i++) 136 if (afdl[i].a_af == family) { 137 afd = &afdl[i]; 138 goto found; 139 } 140 return ENI_FAMILY; 141 142 found: 143 if (salen != afd->a_socklen) 144 return ENI_SALEN; 145 146 port = ((struct sockinet *)sa)->si_port; /* network byte order */ 147 addr = (char *)sa + afd->a_off; 148 149 if (serv == NULL || servlen == 0) { 150 /* 151 * do nothing in this case. 152 * in case you are wondering if "&&" is more correct than 153 * "||" here: RFC2553 says that serv == NULL OR servlen == 0 154 * means that the caller does not want the result. 155 */ 156 } else { 157 if (flags & NI_NUMERICSERV) 158 sp = NULL; 159 else { 160 sp = getservbyport(port, 161 (flags & NI_DGRAM) ? "udp" : "tcp"); 162 } 163 if (sp) { 164 if (strlen(sp->s_name) > servlen) 165 return ENI_MEMORY; 166 strcpy(serv, sp->s_name); 167 } else { 168 snprintf(numserv, sizeof(numserv), "%d", ntohs(port)); 169 if (strlen(numserv) > servlen) 170 return ENI_MEMORY; 171 strcpy(serv, numserv); 172 } 173 } 174 175 switch (sa->sa_family) { 176 case AF_INET: 177 v4a = (u_int32_t) 178 ntohl(((struct sockaddr_in *)sa)->sin_addr.s_addr); 179 if (IN_MULTICAST(v4a) || IN_EXPERIMENTAL(v4a)) 180 flags |= NI_NUMERICHOST; 181 v4a >>= IN_CLASSA_NSHIFT; 182 if (v4a == 0 || v4a == IN_LOOPBACKNET) 183 flags |= NI_NUMERICHOST; 184 break; 185 #ifdef INET6 186 case AF_INET6: 187 { 188 struct sockaddr_in6 *sin6; 189 sin6 = (struct sockaddr_in6 *)sa; 190 switch (sin6->sin6_addr.s6_addr[0]) { 191 case 0x00: 192 if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) 193 ; 194 else if (IN6_IS_ADDR_LOOPBACK(&sin6->sin6_addr)) 195 ; 196 else 197 flags |= NI_NUMERICHOST; 198 break; 199 default: 200 if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr)) { 201 flags |= NI_NUMERICHOST; 202 } 203 else if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) 204 flags |= NI_NUMERICHOST; 205 break; 206 } 207 } 208 break; 209 #endif 210 } 211 if (host == NULL || hostlen == 0) { 212 /* 213 * do nothing in this case. 214 * in case you are wondering if "&&" is more correct than 215 * "||" here: RFC2553 says that host == NULL OR hostlen == 0 216 * means that the caller does not want the result. 217 */ 218 } else if (flags & NI_NUMERICHOST) { 219 /* NUMERICHOST and NAMEREQD conflicts with each other */ 220 if (flags & NI_NAMEREQD) 221 return ENI_NOHOSTNAME; 222 if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr)) 223 == NULL) 224 return ENI_SYSTEM; 225 if (strlen(numaddr) > hostlen) 226 return ENI_MEMORY; 227 strcpy(host, numaddr); 228 #if defined(INET6) && defined(NI_WITHSCOPEID) 229 if (afd->a_af == AF_INET6 && 230 (IN6_IS_ADDR_LINKLOCAL((struct in6_addr *)addr) || 231 IN6_IS_ADDR_MULTICAST((struct in6_addr *)addr)) && 232 ((struct sockaddr_in6 *)sa)->sin6_scope_id) { 233 #ifndef ALWAYS_WITHSCOPE 234 if (flags & NI_WITHSCOPEID) 235 #endif /* !ALWAYS_WITHSCOPE */ 236 { 237 char *ep = strchr(host, '\0'); 238 unsigned int ifindex = 239 ((struct sockaddr_in6 *)sa)->sin6_scope_id; 240 241 *ep = SCOPE_DELIMITER; 242 if ((if_indextoname(ifindex, ep + 1)) == NULL) 243 /* XXX what should we do? */ 244 strncpy(ep + 1, "???", 3); 245 } 246 } 247 #endif /* INET6 */ 248 } else { 249 #ifdef USE_GETIPNODEBY 250 hp = getipnodebyaddr(addr, afd->a_addrlen, afd->a_af, &h_error); 251 #else 252 hp = gethostbyaddr(addr, afd->a_addrlen, afd->a_af); 253 h_error = h_errno; 254 #endif 255 256 if (hp) { 257 if (flags & NI_NOFQDN) { 258 p = strchr(hp->h_name, '.'); 259 if (p) *p = '\0'; 260 } 261 if (strlen(hp->h_name) > hostlen) { 262 #ifdef USE_GETIPNODEBY 263 freehostent(hp); 264 #endif 265 return ENI_MEMORY; 266 } 267 strcpy(host, hp->h_name); 268 #ifdef USE_GETIPNODEBY 269 freehostent(hp); 270 #endif 271 } else { 272 if (flags & NI_NAMEREQD) 273 return ENI_NOHOSTNAME; 274 if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr)) 275 == NULL) 276 return ENI_NOHOSTNAME; 277 if (strlen(numaddr) > hostlen) 278 return ENI_MEMORY; 279 strcpy(host, numaddr); 280 } 281 } 282 return SUCCESS; 283 } 284
Indexes created Tue Sep 30 11:09:46 GMT 2025