about summary refs log tree commit diff
path: root/inet/getnameinfo.c
blob: 95ed6bf3f9a92ba6bf89e6b696219f6a45b3f0d5 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
/* The Inner Net License, Version 2.00

  The author(s) grant permission for redistribution and use in source and
binary forms, with or without modification, of the software and documentation
provided that the following conditions are met:

0. If you receive a version of the software that is specifically labelled
   as not being for redistribution (check the version message and/or README),
   you are not permitted to redistribute that version of the software in any
   way or form.
1. All terms of the all other applicable copyrights and licenses must be
   followed.
2. Redistributions of source code must retain the authors' copyright
   notice(s), this list of conditions, and the following disclaimer.
3. Redistributions in binary form must reproduce the authors' copyright
   notice(s), this list of conditions, and the following disclaimer in the
   documentation and/or other materials provided with the distribution.
4. All advertising materials mentioning features or use of this software
   must display the following acknowledgement with the name(s) of the
   authors as specified in the copyright notice(s) substituted where
   indicated:

	This product includes software developed by <name(s)>, The Inner
	Net, and other contributors.

5. Neither the name(s) of the author(s) nor the names of its contributors
   may be used to endorse or promote products derived from this software
   without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY ITS AUTHORS AND CONTRIBUTORS ``AS IS'' AND ANY
EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE FOR ANY
DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

  If these license terms cause you a real problem, contact the author.  */

/* This software is Copyright 1996 by Craig Metz, All Rights Reserved.  */

#define INET6 1
#define LOCAL 1
#define HOSTTABLE 0
#define RESOLVER 1

#include <sys/types.h>
#include <sys/socket.h>

#include <netinet/in.h>
#if LOCAL
#include <sys/un.h>
#include <sys/utsname.h>
#endif /* LOCAL */
#include <netdb.h>
#include <errno.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>
#include <alloca.h>
#include <libc-lock.h>
#include <arpa/inet.h>

#ifndef AF_LOCAL
#define AF_LOCAL AF_UNIX
#endif /* AF_LOCAL */

#if HOSTTABLE
struct hostent *_addr2hostname_hosts(const char *, int, int);
#endif /* HOSTTABLE */

#ifndef MAXHOSTNAMELEN
#define MAXHOSTNAMELEN 128
#endif

#ifndef min
#define min(x,y) (((x) > (y)) ? (y) : (x))
#endif /* min */

static char *domain;
static char domainbuffer[MAXHOSTNAMELEN];

static char *nrl_domainname(void)
{
  static int first = 1;

  if (first) {

    __libc_lock_define_initialized (static, lock);
    __libc_lock_lock (lock);

    if (first) {
      char *c;
      struct hostent *h, th;
      int tmpbuflen = 1024;
      char *tmpbuf = __alloca(tmpbuflen);
      int herror;

      first = 0;

      while (__gethostbyname_r("localhost", &th, tmpbuf, tmpbuflen, &h,
			       &herror)) {
	if (herror == NETDB_INTERNAL) {
	  if (errno == ERANGE) {
	    tmpbuflen *= 2;
	    tmpbuf = __alloca(tmpbuflen);
	  }
	} else {
	  break;
	}
      }

      if (h && (c = strchr(h->h_name, '.'))) {
	strcpy(domain = domainbuffer, ++c);
	goto ret;
      }

      if (!gethostname(domainbuffer, sizeof(domainbuffer))) {
	if (c = strchr(domainbuffer, '.')) {
	  domain = ++c;
	  goto ret;
	}

	while (__gethostbyname_r(domainbuffer, &th, tmpbuf, tmpbuflen, &h,
				 &herror)) {
	  if (herror == NETDB_INTERNAL) {
	    if (errno == ERANGE) {
	      tmpbuflen *= 2;
	      tmpbuf = __alloca(tmpbuflen);
	    }
	  } else {
	    break;
	  }
	}

	if (h && (c = strchr(h->h_name, '.'))) {
	  strcpy(domain = domainbuffer, ++c);
	  goto ret;
	}
      }

      {
	struct in_addr in_addr;

	in_addr.s_addr = htonl(0x7f000001);

	while (__gethostbyaddr_r((const char *)&in_addr, sizeof(struct in_addr), AF_INET, &th, tmpbuf, tmpbuflen, &h, &herror)) {
	  if (herror == NETDB_INTERNAL) {
	    if (errno == ERANGE) {
	      tmpbuflen *= 2;
	      tmpbuf = __alloca(tmpbuflen);
	    }
	  } else {
	    break;
	  }
	}

	if (h && (c = strchr(h->h_name, '.'))) {
	  domain = domainbuffer, ++c;
	  goto ret;
	}
      }

    }

  ret:
    __libc_lock_unlock (lock);
  };

  return domain;
};

int getnameinfo(const struct sockaddr *sa, size_t addrlen, char *host, size_t hostlen, char *serv, size_t servlen, int flags)
{
  int serrno = errno;
  int tmpbuflen = 1024;
  int herrno;
  char *tmpbuf = __alloca(tmpbuflen);
  struct hostent th;

  if (!sa)
    return -1;

  if (host && (hostlen > 0))
    switch(sa->sa_family) {
      case AF_INET:
#if INET6
      case AF_INET6:
#endif /* INET6 */
	if (!(flags & NI_NUMERICHOST)) {
	  struct hostent *h = NULL;
#if HOSTTABLE
#if INET6
	  if (sa->sa_family == AF_INET6)
	    h = _addr2hostname_hosts((void *)&(((struct sockaddr_in6 *)sa)->sin6_addr), sizeof(struct in6_addr), AF_INET6);
	  else
#endif /* INET6 */
	    h = _addr2hostname_hosts((void *)&(((struct sockaddr_in *)sa)->sin_addr), sizeof(struct in_addr), AF_INET);
#endif /* HOSTTABLE */

#if RESOLVER
	  if (!h) {
#if INET6
	    if (sa->sa_family == AF_INET6) {
	      while (__gethostbyaddr_r((void *)&(((struct sockaddr_in6 *)sa)->sin6_addr), sizeof(struct in6_addr), AF_INET6, &th, tmpbuf, tmpbuflen, &h, &herrno)) {
		if (herrno == NETDB_INTERNAL) {
		  if (errno == ERANGE) {
		    tmpbuflen *= 2;
		    tmpbuf = __alloca(tmpbuflen);
		  } else {
		    __set_h_errno(herrno);
		    goto fail;
		  }
		} else {
		  break;
		}
	      }
	    } else {
#endif /* INET6 */
	      while (__gethostbyaddr_r((void *)&(((struct sockaddr_in *)sa)->sin_addr), sizeof(struct in_addr), AF_INET, &th, tmpbuf, tmpbuflen, &h, &herrno)) {
		if (errno == ERANGE) {
		  tmpbuflen *= 2;
		  tmpbuf = __alloca(tmpbuflen);
		} else {
		  break;
		}
	      }
	    }
	  }
#endif /* RESOLVER */

	  if (h) {
	    if (flags & NI_NOFQDN) {
	      char *c;
	      if ((c = nrl_domainname()) && (c = strstr(h->h_name, c)) && (c != h->h_name) && (*(--c) == '.')) {
		strncpy(host, h->h_name, min(hostlen, (size_t) (c - h->h_name)));
		break;
	      };
	    };
	    strncpy(host, h->h_name, hostlen);
	    break;
	  };
	};

	if (flags & NI_NAMEREQD)
	  goto fail;

        {
	  const char *c;
#if INET6
	  if (sa->sa_family == AF_INET6)
	    c = inet_ntop(AF_INET6, (void *)&(((struct sockaddr_in6 *)sa)->sin6_addr), host, hostlen);
	  else
#endif /* INET6 */
	    c = inet_ntop(AF_INET, (void *)&(((struct sockaddr_in *)sa)->sin_addr), host, hostlen);

	  if (!c)
	    goto fail;
	};
	break;
#if LOCAL
      case AF_LOCAL:
	if (!(flags & NI_NUMERICHOST)) {
	  struct utsname utsname;

	  if (!uname(&utsname)) {
	    strncpy(host, utsname.nodename, hostlen);
	    break;
	  };
	};

	if (flags & NI_NAMEREQD)
	  goto fail;

	strncpy(host, "localhost", hostlen);
	break;
#endif /* LOCAL */
      default:
        return -1;
    };

  if (serv && (servlen > 0))
    switch(sa->sa_family) {
      case AF_INET:
#if INET6
      case AF_INET6:
#endif /* INET6 */
	if (!(flags & NI_NUMERICSERV)) {
	  struct servent *s, ts;
	  while (__getservbyport_r(((struct sockaddr_in *)sa)->sin_port, ((flags & NI_DGRAM) ? "udp" : "tcp"), &ts, tmpbuf, tmpbuflen, &s)) {
	    if (herrno == NETDB_INTERNAL) {
	      if (errno == ERANGE) {
		tmpbuflen *= 2;
		tmpbuf = __alloca(tmpbuflen);
	      } else {
		goto fail;
	      }
	    } else {
	      break;
	    }
	  }
	  if (s) {
	    strncpy(serv, s->s_name, servlen);
	    break;
	  };
	};
	snprintf(serv, servlen, "%d", ntohs(((struct sockaddr_in *)sa)->sin_port));
	break;
#if LOCAL
      case AF_LOCAL:
	strncpy(serv, ((struct sockaddr_un *)sa)->sun_path, servlen);
	break;
#endif /* LOCAL */
    };
  if (host && (hostlen > 0))
    host[hostlen-1] = 0;
  if (serv && (servlen > 0))
    serv[servlen-1] = 0;
  errno = serrno;
  return 0;

fail:
  errno = serrno;
  return -1;
};