1 /*
2 * Issues to be discussed:
3 * - Thread safe-ness must be checked
4 */
5
6 #if ( defined(__linux__) || defined(__linux) || defined(LINUX) )
7 #ifndef IF_NAMESIZE
8 # ifdef IFNAMSIZ
9 # define IF_NAMESIZE IFNAMSIZ
10 # else
11 # define IF_NAMESIZE 16
12 # endif
13 #endif
14 #endif
15
16 /*
17 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
18 * All rights reserved.
19 *
20 * Redistribution and use in source and binary forms, with or without
21 * modification, are permitted provided that the following conditions
22 * are met:
23 * 1. Redistributions of source code must retain the above copyright
24 * notice, this list of conditions and the following disclaimer.
25 * 2. Redistributions in binary form must reproduce the above copyright
26 * notice, this list of conditions and the following disclaimer in the
27 * documentation and/or other materials provided with the distribution.
28 * 3. All advertising materials mentioning features or use of this software
29 * must display the following acknowledgement:
30 * This product includes software developed by WIDE Project and
31 * its contributors.
32 * 4. Neither the name of the project nor the names of its contributors
33 * may be used to endorse or promote products derived from this software
34 * without specific prior written permission.
35 *
36 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
37 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
38 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
39 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
40 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
41 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
42 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
43 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
44 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
45 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
46 * SUCH DAMAGE.
47 */
48
49 #include <port_before.h>
50
51 #include <sys/types.h>
52 #include <sys/socket.h>
53
54 #include <netinet/in.h>
55 #include <arpa/nameser.h>
56 #include <arpa/inet.h>
57 #include <net/if.h>
58
59 #include <netdb.h>
60 #include <resolv.h>
61 #include <string.h>
62 #include <stddef.h>
63
64 #include <port_after.h>
65
66 /*%
67 * Note that a_off will be dynamically adjusted so that to be consistent
68 * with the definition of sockaddr_in{,6}.
69 * The value presented below is just a guess.
70 */
71 static struct afd {
72 int a_af;
73 int a_addrlen;
74 size_t a_socklen;
75 int a_off;
76 } afdl [] = {
77 /* first entry is linked last... */
78 {PF_INET, sizeof(struct in_addr), sizeof(struct sockaddr_in),
79 offsetof(struct sockaddr_in, sin_addr)},
80 {PF_INET6, sizeof(struct in6_addr), sizeof(struct sockaddr_in6),
81 offsetof(struct sockaddr_in6, sin6_addr)},
82 {0, 0, 0, 0},
83 };
84
85 struct sockinet {
86 #ifdef HAVE_SA_LEN
87 u_char si_len;
88 #endif
89 u_char si_family;
90 u_short si_port;
91 };
92
93 static int ip6_parsenumeric __P((const struct sockaddr *, const char *, char *,
94 size_t, int));
95 #ifdef HAVE_SIN6_SCOPE_ID
96 static int ip6_sa2str __P((const struct sockaddr_in6 *, char *, size_t, int));
97 #endif
98
99 int
getnameinfo(sa,salen,host,hostlen,serv,servlen,flags)100 getnameinfo(sa, salen, host, hostlen, serv, servlen, flags)
101 const struct sockaddr *sa;
102 size_t salen;
103 char *host;
104 size_t hostlen;
105 char *serv;
106 size_t servlen;
107 int flags;
108 {
109 struct afd *afd;
110 struct servent *sp;
111 struct hostent *hp;
112 u_short port;
113 #ifdef HAVE_SA_LEN
114 size_t len;
115 #endif
116 int family, i;
117 const char *addr;
118 char *p;
119 char numserv[512];
120 char numaddr[512];
121 const struct sockaddr_in6 *sin6;
122
123 if (sa == NULL)
124 return EAI_FAIL;
125
126 #ifdef HAVE_SA_LEN
127 len = sa->sa_len;
128 if (len != salen) return EAI_FAIL;
129 #endif
130
131 family = sa->sa_family;
132 for (i = 0; afdl[i].a_af; i++)
133 if (afdl[i].a_af == family) {
134 afd = &afdl[i];
135 goto found;
136 }
137 return EAI_FAMILY;
138
139 found:
140 if (salen != afd->a_socklen) return EAI_FAIL;
141
142 port = ((const struct sockinet *)sa)->si_port; /*%< network byte order */
143 addr = (const char *)sa + afd->a_off;
144
145 if (serv == NULL || servlen == 0U) {
146 /*
147 * rfc2553bis says that serv == NULL or servlen == 0 means that
148 * the caller does not want the result.
149 */
150 } else if (flags & NI_NUMERICSERV) {
151 sprintf(numserv, "%d", ntohs(port));
152 if (strlen(numserv) > servlen)
153 return EAI_MEMORY;
154 strcpy(serv, numserv);
155 } else {
156 sp = getservbyport(port, (flags & NI_DGRAM) ? "udp" : "tcp");
157 if (sp) {
158 if (strlen(sp->s_name) + 1 > servlen)
159 return EAI_MEMORY;
160 strcpy(serv, sp->s_name);
161 } else
162 return EAI_NONAME;
163 }
164
165 switch (sa->sa_family) {
166 case AF_INET:
167 if (ntohl(*(const u_int32_t *)addr) >> IN_CLASSA_NSHIFT == 0)
168 flags |= NI_NUMERICHOST;
169 break;
170 case AF_INET6:
171 sin6 = (const struct sockaddr_in6 *)sa;
172 switch (sin6->sin6_addr.s6_addr[0]) {
173 case 0x00:
174 if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr))
175 ;
176 else if (IN6_IS_ADDR_LOOPBACK(&sin6->sin6_addr))
177 ;
178 else
179 flags |= NI_NUMERICHOST;
180 break;
181 default:
182 if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr))
183 flags |= NI_NUMERICHOST;
184 else if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))
185 flags |= NI_NUMERICHOST;
186 break;
187 }
188 break;
189 }
190 if (host == NULL || hostlen == 0U) {
191 /*
192 * rfc2553bis says that host == NULL or hostlen == 0 means that
193 * the caller does not want the result.
194 */
195 } else if (flags & NI_NUMERICHOST) {
196 goto numeric;
197 } else {
198 hp = gethostbyaddr(addr, afd->a_addrlen, afd->a_af);
199
200 if (hp) {
201 if (flags & NI_NOFQDN) {
202 p = strchr(hp->h_name, '.');
203 if (p) *p = '\0';
204 }
205 if (strlen(hp->h_name) + 1 > hostlen)
206 return EAI_MEMORY;
207 strcpy(host, hp->h_name);
208 } else {
209 if (flags & NI_NAMEREQD)
210 return EAI_NONAME;
211 numeric:
212 switch(afd->a_af) {
213 case AF_INET6:
214 {
215 int error;
216
217 if ((error = ip6_parsenumeric(sa, addr, host,
218 hostlen,
219 flags)) != 0)
220 return(error);
221 break;
222 }
223
224 default:
225 if (inet_ntop(afd->a_af, addr, numaddr,
226 sizeof(numaddr)) == NULL)
227 return EAI_NONAME;
228 if (strlen(numaddr) + 1 > hostlen)
229 return EAI_MEMORY;
230 strcpy(host, numaddr);
231 }
232 }
233 }
234 return(0);
235 }
236
237 static int
ip6_parsenumeric(const struct sockaddr * sa,const char * addr,char * host,size_t hostlen,int flags)238 ip6_parsenumeric(const struct sockaddr *sa, const char *addr, char *host,
239 size_t hostlen, int flags)
240 {
241 size_t numaddrlen;
242 char numaddr[512];
243
244 #ifndef HAVE_SIN6_SCOPE_ID
245 UNUSED(sa);
246 UNUSED(flags);
247 #endif
248
249 if (inet_ntop(AF_INET6, addr, numaddr, sizeof(numaddr))
250 == NULL)
251 return EAI_SYSTEM;
252
253 numaddrlen = strlen(numaddr);
254 if (numaddrlen + 1 > hostlen) /*%< don't forget terminator */
255 return EAI_MEMORY;
256 strcpy(host, numaddr);
257
258 #ifdef HAVE_SIN6_SCOPE_ID
259 if (((const struct sockaddr_in6 *)sa)->sin6_scope_id) {
260 char scopebuf[MAXHOSTNAMELEN]; /*%< XXX */
261 int scopelen;
262
263 /* ip6_sa2str never fails */
264 scopelen = ip6_sa2str((const struct sockaddr_in6 *)sa,
265 scopebuf, sizeof(scopebuf), flags);
266
267 if (scopelen + 1 + numaddrlen + 1 > hostlen)
268 return EAI_MEMORY;
269
270 /* construct <numeric-addr><delim><scopeid> */
271 memcpy(host + numaddrlen + 1, scopebuf,
272 scopelen);
273 host[numaddrlen] = SCOPE_DELIMITER;
274 host[numaddrlen + 1 + scopelen] = '\0';
275 }
276 #endif
277
278 return 0;
279 }
280
281 #ifdef HAVE_SIN6_SCOPE_ID
282 /* ARGSUSED */
283 static int
ip6_sa2str(const struct sockaddr_in6 * sa6,char * buf,size_t bufsiz,int flags)284 ip6_sa2str(const struct sockaddr_in6 *sa6, char *buf,
285 size_t bufsiz, int flags)
286 {
287 #ifdef USE_IFNAMELINKID
288 unsigned int ifindex = (unsigned int)sa6->sin6_scope_id;
289 const struct in6_addr *a6 = &sa6->sin6_addr;
290 #endif
291 char tmp[64];
292
293 #ifdef NI_NUMERICSCOPE
294 if (flags & NI_NUMERICSCOPE) {
295 sprintf(tmp, "%u", sa6->sin6_scope_id);
296 if (bufsiz != 0U) {
297 strncpy(buf, tmp, bufsiz - 1);
298 buf[bufsiz - 1] = '\0';
299 }
300 return(strlen(tmp));
301 }
302 #endif
303
304 #ifdef USE_IFNAMELINKID
305 /*
306 * For a link-local address, convert the index to an interface
307 * name, assuming a one-to-one mapping between links and interfaces.
308 * Note, however, that this assumption is stronger than the
309 * specification of the scoped address architecture; the
310 * specficication says that more than one interfaces can belong to
311 * a single link.
312 */
313
314 /* if_indextoname() does not take buffer size. not a good api... */
315 if ((IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) &&
316 bufsiz >= IF_NAMESIZE) {
317 char *p = if_indextoname(ifindex, buf);
318 if (p) {
319 return(strlen(p));
320 }
321 }
322 #endif
323
324 /* last resort */
325 sprintf(tmp, "%u", sa6->sin6_scope_id);
326 if (bufsiz != 0U) {
327 strncpy(buf, tmp, bufsiz - 1);
328 buf[bufsiz - 1] = '\0';
329 }
330 return(strlen(tmp));
331 }
332 #endif
333
334 /*! \file */
335