2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
31 * Issues to be discussed:
32 * - Thread safe-ness must be checked
33 * - Return values. There seems to be no standard for return value (RFC2553)
34 * but INRIA implementation returns EAI_xxx defined for getaddrinfo().
35 * - RFC2553 says that we should raise error on short buffer. X/Open says
36 * we need to truncate the result. We obey RFC2553 (and X/Open should be
45 static const char rcsid[] _U_ =
46 "@(#) $Header: /tcpdump/master/tcpdump/missing/getnameinfo.c,v 1.11 2003-11-16 09:36:49 guy Exp $";
49 #include <sys/types.h>
50 #include <sys/socket.h>
52 #include <netinet/in.h>
53 #include <arpa/inet.h>
54 #include <arpa/nameser.h>
61 #ifdef NEED_ADDRINFO_H
77 {PF_INET6, sizeof(struct in6_addr), sizeof(struct sockaddr_in6),
78 offsetof(struct sockaddr_in6, sin6_addr)},
80 {PF_INET, sizeof(struct in_addr), sizeof(struct sockaddr_in),
81 offsetof(struct sockaddr_in, sin_addr)},
91 #define ENI_NOSOCKET 0
92 #define ENI_NOSERVNAME 1
93 #define ENI_NOHOSTNAME 2
100 getnameinfo(sa, salen, host, hostlen, serv, servlen, flags)
101 const struct sockaddr *sa;
123 #ifdef HAVE_SA_LEN /*XXX*/
124 if (sa->sa_len != salen)
128 family = sa->sa_family;
129 for (i = 0; afdl[i].a_af; i++)
130 if (afdl[i].a_af == family) {
137 if (salen != afd->a_socklen)
140 port = ((struct sockinet *)sa)->si_port; /* network byte order */
141 addr = (char *)sa + afd->a_off;
143 if (serv == NULL || servlen == 0) {
145 * do nothing in this case.
146 * in case you are wondering if "&&" is more correct than
147 * "||" here: RFC2553 says that serv == NULL OR servlen == 0
148 * means that the caller does not want the result.
151 if (flags & NI_NUMERICSERV)
154 sp = getservbyport(port,
155 (flags & NI_DGRAM) ? "udp" : "tcp");
158 if (strlen(sp->s_name) + 1 > servlen)
160 strcpy(serv, sp->s_name);
162 snprintf(numserv, sizeof(numserv), "%d", ntohs(port));
163 if (strlen(numserv) + 1 > servlen)
165 strcpy(serv, numserv);
169 switch (sa->sa_family) {
172 ntohl(((struct sockaddr_in *)sa)->sin_addr.s_addr);
173 if (IN_MULTICAST(v4a) || IN_EXPERIMENTAL(v4a))
174 flags |= NI_NUMERICHOST;
175 v4a >>= IN_CLASSA_NSHIFT;
177 flags |= NI_NUMERICHOST;
182 struct sockaddr_in6 *sin6;
183 sin6 = (struct sockaddr_in6 *)sa;
184 switch (sin6->sin6_addr.s6_addr[0]) {
186 if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr))
188 else if (IN6_IS_ADDR_LOOPBACK(&sin6->sin6_addr))
191 flags |= NI_NUMERICHOST;
194 if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr)) {
195 flags |= NI_NUMERICHOST;
197 else if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))
198 flags |= NI_NUMERICHOST;
205 if (host == NULL || hostlen == 0) {
207 * do nothing in this case.
208 * in case you are wondering if "&&" is more correct than
209 * "||" here: RFC2553 says that host == NULL OR hostlen == 0
210 * means that the caller does not want the result.
212 } else if (flags & NI_NUMERICHOST) {
213 /* NUMERICHOST and NAMEREQD conflicts with each other */
214 if (flags & NI_NAMEREQD)
215 return ENI_NOHOSTNAME;
216 if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr))
219 if (strlen(numaddr) + 1 > hostlen)
221 strcpy(host, numaddr);
222 #if defined(INET6) && defined(NI_WITHSCOPEID)
223 if (afd->a_af == AF_INET6 &&
224 (IN6_IS_ADDR_LINKLOCAL((struct in6_addr *)addr) ||
225 IN6_IS_ADDR_MULTICAST((struct in6_addr *)addr)) &&
226 ((struct sockaddr_in6 *)sa)->sin6_scope_id) {
227 #ifndef ALWAYS_WITHSCOPE
228 if (flags & NI_WITHSCOPEID)
229 #endif /* !ALWAYS_WITHSCOPE */
231 char *ep = strchr(host, '\0');
232 unsigned int ifindex =
233 ((struct sockaddr_in6 *)sa)->sin6_scope_id;
235 *ep = SCOPE_DELIMITER;
236 if ((if_indextoname(ifindex, ep + 1)) == NULL)
237 /* XXX what should we do? */
238 strncpy(ep + 1, "???", 3);
243 #ifdef USE_GETIPNODEBY
244 hp = getipnodebyaddr(addr, afd->a_addrlen, afd->a_af, &h_error);
246 hp = gethostbyaddr(addr, afd->a_addrlen, afd->a_af);
255 if (flags & NI_NOFQDN) {
256 p = strchr(hp->h_name, '.');
259 if (strlen(hp->h_name) + 1 > hostlen) {
260 #ifdef USE_GETIPNODEBY
265 strcpy(host, hp->h_name);
266 #ifdef USE_GETIPNODEBY
270 if (flags & NI_NAMEREQD)
271 return ENI_NOHOSTNAME;
272 if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr))
274 return ENI_NOHOSTNAME;
275 if (strlen(numaddr) + 1 > hostlen)
277 strcpy(host, numaddr);