xref: /titanic_41/usr/src/lib/libresolv2/common/irs/lcl_nw.c (revision 9525b14bcdeb5b5f6f95ab27c2f48f18bd2ec829)
1 /*
2  * Copyright (c) 1989, 1993, 1995
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
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. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 /*
35  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
36  * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
37  *
38  * Permission to use, copy, modify, and distribute this software for any
39  * purpose with or without fee is hereby granted, provided that the above
40  * copyright notice and this permission notice appear in all copies.
41  *
42  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
43  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
44  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
45  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
46  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
47  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
48  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
49  */
50 
51 #if defined(LIBC_SCCS) && !defined(lint)
52 static const char rcsid[] = "$Id: lcl_nw.c,v 1.4 2005/04/27 04:56:31 sra Exp $";
53 /* from getgrent.c 8.2 (Berkeley) 3/21/94"; */
54 /* from BSDI Id: getgrent.c,v 2.8 1996/05/28 18:15:14 bostic Exp $	*/
55 #endif /* LIBC_SCCS and not lint */
56 
57 /* Imports */
58 
59 #include "port_before.h"
60 
61 #include <sys/types.h>
62 #include <sys/socket.h>
63 
64 #include <netinet/in.h>
65 #include <arpa/inet.h>
66 #include <arpa/nameser.h>
67 
68 #include <errno.h>
69 #include <fcntl.h>
70 #include <resolv.h>
71 #include <stdio.h>
72 #include <stdlib.h>
73 #include <string.h>
74 
75 #include <irs.h>
76 #include <isc/memcluster.h>
77 
78 #include "port_after.h"
79 
80 #include <isc/misc.h>
81 #include "irs_p.h"
82 #include "lcl_p.h"
83 
84 #define MAXALIASES 35
85 #define MAXADDRSIZE 4
86 
87 struct pvt {
88 	FILE *		fp;
89 	char 		line[BUFSIZ+1];
90 	struct nwent 	net;
91 	char *		aliases[MAXALIASES];
92 	char		addr[MAXADDRSIZE];
93 	struct __res_state *  res;
94 	void		(*free_res)(void *);
95 };
96 
97 /* Forward */
98 
99 static void 		nw_close(struct irs_nw *);
100 static struct nwent *	nw_byname(struct irs_nw *, const char *, int);
101 static struct nwent *	nw_byaddr(struct irs_nw *, void *, int, int);
102 static struct nwent *	nw_next(struct irs_nw *);
103 static void		nw_rewind(struct irs_nw *);
104 static void		nw_minimize(struct irs_nw *);
105 static struct __res_state * nw_res_get(struct irs_nw *this);
106 static void		nw_res_set(struct irs_nw *this,
107 				   struct __res_state *res,
108 				   void (*free_res)(void *));
109 
110 static int		init(struct irs_nw *this);
111 
112 /* Portability. */
113 
114 #ifndef SEEK_SET
115 # define SEEK_SET 0
116 #endif
117 
118 /* Public */
119 
120 struct irs_nw *
irs_lcl_nw(struct irs_acc * this)121 irs_lcl_nw(struct irs_acc *this) {
122 	struct irs_nw *nw;
123 	struct pvt *pvt;
124 
125 	UNUSED(this);
126 
127 	if (!(pvt = memget(sizeof *pvt))) {
128 		errno = ENOMEM;
129 		return (NULL);
130 	}
131 	memset(pvt, 0, sizeof *pvt);
132 	if (!(nw = memget(sizeof *nw))) {
133 		memput(pvt, sizeof *pvt);
134 		errno = ENOMEM;
135 		return (NULL);
136 	}
137 	memset(nw, 0x5e, sizeof *nw);
138 	nw->private = pvt;
139 	nw->close = nw_close;
140 	nw->byname = nw_byname;
141 	nw->byaddr = nw_byaddr;
142 	nw->next = nw_next;
143 	nw->rewind = nw_rewind;
144 	nw->minimize = nw_minimize;
145 	nw->res_get = nw_res_get;
146 	nw->res_set = nw_res_set;
147 	return (nw);
148 }
149 
150 /* Methods */
151 
152 static void
nw_close(struct irs_nw * this)153 nw_close(struct irs_nw *this) {
154 	struct pvt *pvt = (struct pvt *)this->private;
155 
156 	nw_minimize(this);
157 	if (pvt->res && pvt->free_res)
158 		(*pvt->free_res)(pvt->res);
159 	if (pvt->fp)
160 		(void)fclose(pvt->fp);
161 	memput(pvt, sizeof *pvt);
162 	memput(this, sizeof *this);
163 }
164 
165 static struct nwent *
nw_byaddr(struct irs_nw * this,void * net,int length,int type)166 nw_byaddr(struct irs_nw *this, void *net, int length, int type) {
167 	struct nwent *p;
168 
169 	if (init(this) == -1)
170 		return(NULL);
171 
172 	nw_rewind(this);
173 	while ((p = nw_next(this)) != NULL)
174 		if (p->n_addrtype == type && p->n_length == length)
175 			if (bitncmp(p->n_addr, net, length) == 0)
176 				break;
177 	return (p);
178 }
179 
180 static struct nwent *
nw_byname(struct irs_nw * this,const char * name,int type)181 nw_byname(struct irs_nw *this, const char *name, int type) {
182 	struct nwent *p;
183 	char **ap;
184 
185 	if (init(this) == -1)
186 		return(NULL);
187 
188 	nw_rewind(this);
189 	while ((p = nw_next(this)) != NULL) {
190 		if (ns_samename(p->n_name, name) == 1 &&
191 		    p->n_addrtype == type)
192 			break;
193 		for (ap = p->n_aliases; *ap; ap++)
194 			if ((ns_samename(*ap, name) == 1) &&
195 			    (p->n_addrtype == type))
196 				goto found;
197 	}
198  found:
199 	return (p);
200 }
201 
202 static void
nw_rewind(struct irs_nw * this)203 nw_rewind(struct irs_nw *this) {
204 	struct pvt *pvt = (struct pvt *)this->private;
205 
206 	if (pvt->fp) {
207 		if (fseek(pvt->fp, 0L, SEEK_SET) == 0)
208 			return;
209 		(void)fclose(pvt->fp);
210 	}
211 	if (!(pvt->fp = fopen(_PATH_NETWORKS, "r")))
212 		return;
213 	if (fcntl(fileno(pvt->fp), F_SETFD, 1) < 0) {
214 		(void)fclose(pvt->fp);
215 		pvt->fp = NULL;
216 	}
217 }
218 
219 static struct nwent *
nw_next(struct irs_nw * this)220 nw_next(struct irs_nw *this) {
221 	struct pvt *pvt = (struct pvt *)this->private;
222 	struct nwent *ret = NULL;
223 	char *p, *cp, **q;
224 	char *bufp, *ndbuf, *dbuf = NULL;
225 	int c, bufsiz, offset = 0;
226 
227 	if (init(this) == -1)
228 		return(NULL);
229 
230 	if (pvt->fp == NULL)
231 		nw_rewind(this);
232 	if (pvt->fp == NULL) {
233 		RES_SET_H_ERRNO(pvt->res, NETDB_INTERNAL);
234 		return (NULL);
235 	}
236 	bufp = pvt->line;
237 	bufsiz = sizeof(pvt->line);
238 
239  again:
240 	p = fgets(bufp + offset, bufsiz - offset, pvt->fp);
241 	if (p == NULL)
242 		goto cleanup;
243 	if (!strchr(p, '\n') && !feof(pvt->fp)) {
244 #define GROWBUF 1024
245 		/* allocate space for longer line */
246 	  	if (dbuf == NULL) {
247 			if ((ndbuf = malloc(bufsiz + GROWBUF)) != NULL)
248 				strcpy(ndbuf, bufp);
249 		} else
250 			ndbuf = realloc(dbuf, bufsiz + GROWBUF);
251 		if (ndbuf) {
252 			dbuf = ndbuf;
253 			bufp = dbuf;
254 			bufsiz += GROWBUF;
255 			offset = strlen(dbuf);
256 		} else {
257 			/* allocation failed; skip this long line */
258 			while ((c = getc(pvt->fp)) != EOF)
259 				if (c == '\n')
260 					break;
261 			if (c != EOF)
262 				ungetc(c, pvt->fp);
263 		}
264 		goto again;
265 	}
266 
267 	p -= offset;
268 	offset = 0;
269 
270 	if (*p == '#')
271 		goto again;
272 
273 	cp = strpbrk(p, "#\n");
274 	if (cp != NULL)
275 		*cp = '\0';
276 	pvt->net.n_name = p;
277 	cp = strpbrk(p, " \t");
278 	if (cp == NULL)
279 		goto again;
280 	*cp++ = '\0';
281 	while (*cp == ' ' || *cp == '\t')
282 		cp++;
283 	p = strpbrk(cp, " \t");
284 	if (p != NULL)
285 		*p++ = '\0';
286 	pvt->net.n_length = inet_net_pton(AF_INET, cp, pvt->addr,
287 					  sizeof pvt->addr);
288 	if (pvt->net.n_length < 0)
289 		goto again;
290 	pvt->net.n_addrtype = AF_INET;
291 	pvt->net.n_addr = pvt->addr;
292 	q = pvt->net.n_aliases = pvt->aliases;
293 	if (p != NULL) {
294 		cp = p;
295 		while (cp && *cp) {
296 			if (*cp == ' ' || *cp == '\t') {
297 				cp++;
298 				continue;
299 			}
300 			if (q < &pvt->aliases[MAXALIASES - 1])
301 				*q++ = cp;
302 			cp = strpbrk(cp, " \t");
303 			if (cp != NULL)
304 				*cp++ = '\0';
305 		}
306 	}
307 	*q = NULL;
308 	ret = &pvt->net;
309 
310  cleanup:
311 	if (dbuf)
312 		free(dbuf);
313 
314 	return (ret);
315 }
316 
317 static void
nw_minimize(struct irs_nw * this)318 nw_minimize(struct irs_nw *this) {
319 	struct pvt *pvt = (struct pvt *)this->private;
320 
321 	if (pvt->res)
322 		res_nclose(pvt->res);
323 	if (pvt->fp != NULL) {
324 		(void)fclose(pvt->fp);
325 		pvt->fp = NULL;
326 	}
327 }
328 
329 static struct __res_state *
nw_res_get(struct irs_nw * this)330 nw_res_get(struct irs_nw *this) {
331 	struct pvt *pvt = (struct pvt *)this->private;
332 
333 	if (!pvt->res) {
334 		struct __res_state *res;
335 		res = (struct __res_state *)malloc(sizeof *res);
336 		if (!res) {
337 			errno = ENOMEM;
338 			return (NULL);
339 		}
340 		memset(res, 0, sizeof *res);
341 		nw_res_set(this, res, free);
342 	}
343 
344 	return (pvt->res);
345 }
346 
347 static void
nw_res_set(struct irs_nw * this,struct __res_state * res,void (* free_res)(void *))348 nw_res_set(struct irs_nw *this, struct __res_state *res,
349 		void (*free_res)(void *)) {
350 	struct pvt *pvt = (struct pvt *)this->private;
351 
352 	if (pvt->res && pvt->free_res) {
353 		res_nclose(pvt->res);
354 		(*pvt->free_res)(pvt->res);
355 	}
356 
357 	pvt->res = res;
358 	pvt->free_res = free_res;
359 }
360 
361 static int
init(struct irs_nw * this)362 init(struct irs_nw *this) {
363 	struct pvt *pvt = (struct pvt *)this->private;
364 
365 	if (!pvt->res && !nw_res_get(this))
366 		return (-1);
367 	if (((pvt->res->options & RES_INIT) == 0U) &&
368 	    res_ninit(pvt->res) == -1)
369 		return (-1);
370 	return (0);
371 }
372 
373 /*! \file */
374