xref: /illumos-gate/usr/src/lib/libresolv2/common/irs/gen.c (revision 4eaa471005973e11a6110b69fe990530b3b95a38)
1 /*
2  * Copyright 1997-2002 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 
6 /*
7  * Copyright (c) 1996-1999 by Internet Software Consortium.
8  *
9  * Permission to use, copy, modify, and distribute this software for any
10  * purpose with or without fee is hereby granted, provided that the above
11  * copyright notice and this permission notice appear in all copies.
12  *
13  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
14  * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
15  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
16  * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
17  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
18  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
19  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
20  * SOFTWARE.
21  */
22 
23 #pragma ident	"%Z%%M%	%I%	%E% SMI"
24 
25 #if !defined(LINT) && !defined(CODECENTER)
26 static const char rcsid[] = "$Id: gen.c,v 1.26 2001/05/29 05:48:35 marka Exp $";
27 #endif
28 
29 /*
30  * this is the top level dispatcher
31  *
32  * The dispatcher is implemented as an accessor class; it is an
33  * accessor class that calls other accessor classes, as controlled by a
34  * configuration file.
35  *
36  * A big difference between this accessor class and others is that the
37  * map class initializers are NULL, and the map classes are already
38  * filled in with method functions that will do the right thing.
39  */
40 
41 /* Imports */
42 
43 #include "port_before.h"
44 
45 #include <isc/assertions.h>
46 #include <ctype.h>
47 #include <errno.h>
48 #include <stdio.h>
49 #include <stdlib.h>
50 #include <string.h>
51 
52 #include <sys/types.h>
53 #include <netinet/in.h>
54 #include <arpa/nameser.h>
55 #include <resolv.h>
56 
57 #include <isc/memcluster.h>
58 #include <irs.h>
59 
60 #include "port_after.h"
61 
62 #include "irs_p.h"
63 #include "gen_p.h"
64 
65 #ifdef SUNW_HOSTS_FALLBACK
66 extern int __res_no_hosts_fallback(void);
67 #endif /* SUNW_HOSTS_FALLBACK */
68 
69 /* Definitions */
70 
71 struct nameval {
72 	const char *	name;
73 	int		val;
74 };
75 
76 static const struct nameval acc_names[irs_nacc+1] = {
77 	{ "local", irs_lcl },
78 	{ "dns", irs_dns },
79 	{ "nis", irs_nis },
80 	{ "irp", irs_irp },
81 	{ NULL, irs_nacc }
82 };
83 
84 typedef struct irs_acc *(*accinit) __P((const char *options));
85 
86 static const accinit accs[irs_nacc+1] = {
87 	irs_lcl_acc,
88 	irs_dns_acc,
89 #ifdef WANT_IRS_NIS
90 	irs_nis_acc,
91 #else
92 	NULL,
93 #endif
94 	irs_irp_acc,
95 	NULL
96 };
97 
98 static const struct nameval map_names[irs_nmap+1] = {
99 	{ "group", irs_gr },
100 	{ "passwd", irs_pw },
101 	{ "services", irs_sv },
102 	{ "protocols", irs_pr },
103 	{ "hosts", irs_ho },
104 	{ "networks", irs_nw },
105 	{ "netgroup", irs_ng },
106 	{ NULL, irs_nmap }
107 };
108 
109 static const struct nameval option_names[] = {
110 	{ "merge", IRS_MERGE },
111 	{ "continue", IRS_CONTINUE },
112 	{ NULL, 0 }
113 };
114 
115 /* Forward */
116 
117 static void		gen_close(struct irs_acc *);
118 static struct __res_state * gen_res_get(struct irs_acc *);
119 static void		gen_res_set(struct irs_acc *, struct __res_state *,
120 				    void (*)(void *));
121 static int		find_name(const char *, const struct nameval nv[]);
122 static void 		init_map_rules(struct gen_p *, const char *conf_file);
123 static struct irs_rule *release_rule(struct irs_rule *);
124 static int		add_rule(struct gen_p *,
125 				 enum irs_map_id, enum irs_acc_id,
126 				 const char *);
127 
128 /* Public */
129 
130 struct irs_acc *
131 irs_gen_acc(const char *options, const char *conf_file) {
132 	struct irs_acc *acc;
133 	struct gen_p *irs;
134 
135 	if (!(acc = memget(sizeof *acc))) {
136 		errno = ENOMEM;
137 		return (NULL);
138 	}
139 	memset(acc, 0x5e, sizeof *acc);
140 	if (!(irs = memget(sizeof *irs))) {
141 		errno = ENOMEM;
142 		memput(acc, sizeof *acc);
143 		return (NULL);
144 	}
145 	memset(irs, 0x5e, sizeof *irs);
146 	irs->options = strdup(options);
147 	irs->res = NULL;
148 	irs->free_res = NULL;
149 	memset(irs->accessors, 0, sizeof irs->accessors);
150 	memset(irs->map_rules, 0, sizeof irs->map_rules);
151 	init_map_rules(irs, conf_file);
152 	acc->private = irs;
153 #ifdef WANT_IRS_GR
154 	acc->gr_map = irs_gen_gr;
155 #else
156 	acc->gr_map = NULL;
157 #endif
158 #ifdef WANT_IRS_PW
159 	acc->pw_map = irs_gen_pw;
160 #else
161 	acc->pw_map = NULL;
162 #endif
163 	acc->sv_map = irs_gen_sv;
164 	acc->pr_map = irs_gen_pr;
165 	acc->ho_map = irs_gen_ho;
166 	acc->nw_map = irs_gen_nw;
167 	acc->ng_map = irs_gen_ng;
168 	acc->res_get = gen_res_get;
169 	acc->res_set = gen_res_set;
170 	acc->close = gen_close;
171 	return (acc);
172 }
173 
174 /* Methods */
175 
176 static struct __res_state *
177 gen_res_get(struct irs_acc *this) {
178 	struct gen_p *irs = (struct gen_p *)this->private;
179 
180 	if (irs->res == NULL) {
181 		struct __res_state *res;
182 		res = (struct __res_state *)malloc(sizeof *res);
183 		if (res == NULL)
184 			return (NULL);
185 		memset(res, 0, sizeof *res);
186 		gen_res_set(this, res, free);
187 	}
188 
189 	if (((irs->res->options & RES_INIT) == 0) && res_ninit(irs->res) < 0)
190 		return (NULL);
191 
192 	return (irs->res);
193 }
194 
195 static void
196 gen_res_set(struct irs_acc *this, struct __res_state *res,
197 	    void (*free_res)(void *)) {
198 	struct gen_p *irs = (struct gen_p *)this->private;
199 #if 0
200 	struct irs_rule *rule;
201 	struct irs_ho *ho;
202 	struct irs_nw *nw;
203 #endif
204 
205 	if (irs->res && irs->free_res) {
206 		res_nclose(irs->res);
207 		(*irs->free_res)(irs->res);
208 	}
209 
210 	irs->res = res;
211 	irs->free_res = free_res;
212 
213 #if 0
214 	for (rule = irs->map_rules[irs_ho]; rule; rule = rule->next) {
215                 ho = rule->inst->ho;
216 
217                 (*ho->res_set)(ho, res, NULL);
218 	}
219 	for (rule = irs->map_rules[irs_nw]; rule; rule = rule->next) {
220                 nw = rule->inst->nw;
221 
222                 (*nw->res_set)(nw, res, NULL);
223 	}
224 #endif
225 }
226 
227 static void
228 gen_close(struct irs_acc *this) {
229 	struct gen_p *irs = (struct gen_p *)this->private;
230 	int n;
231 
232 	/* Search rules. */
233 	for (n = 0; n < irs_nmap; n++)
234 		while (irs->map_rules[n] != NULL)
235 			irs->map_rules[n] = release_rule(irs->map_rules[n]);
236 
237 	/* Access methods. */
238 	for (n = 0; n < irs_nacc; n++) {
239 		/* Map objects. */
240 		if (irs->accessors[n].gr != NULL)
241 			(*irs->accessors[n].gr->close)(irs->accessors[n].gr);
242 		if (irs->accessors[n].pw != NULL)
243 			(*irs->accessors[n].pw->close)(irs->accessors[n].pw);
244 		if (irs->accessors[n].sv != NULL)
245 			(*irs->accessors[n].sv->close)(irs->accessors[n].sv);
246 		if (irs->accessors[n].pr != NULL)
247 			(*irs->accessors[n].pr->close)(irs->accessors[n].pr);
248 		if (irs->accessors[n].ho != NULL)
249 			(*irs->accessors[n].ho->close)(irs->accessors[n].ho);
250 		if (irs->accessors[n].nw != NULL)
251 			(*irs->accessors[n].nw->close)(irs->accessors[n].nw);
252 		if (irs->accessors[n].ng != NULL)
253 			(*irs->accessors[n].ng->close)(irs->accessors[n].ng);
254 		/* Enclosing accessor. */
255 		if (irs->accessors[n].acc != NULL)
256 			(*irs->accessors[n].acc->close)(irs->accessors[n].acc);
257 	}
258 
259 	/* The options string was strdup'd. */
260 	free((void*)irs->options);
261 
262 	if (irs->res && irs->free_res)
263 		(*irs->free_res)(irs->res);
264 
265 	/* The private data container. */
266 	memput(irs, sizeof *irs);
267 
268 	/* The object. */
269 	memput(this, sizeof *this);
270 }
271 
272 /* Private */
273 
274 static int
275 find_name(const char *name, const struct nameval names[]) {
276 	int n;
277 
278 	for (n = 0; names[n].name != NULL; n++)
279 		if (strcmp(name, names[n].name) == 0)
280 			return (names[n].val);
281 	return (-1);
282 }
283 
284 static struct irs_rule *
285 release_rule(struct irs_rule *rule) {
286 	struct irs_rule *next = rule->next;
287 
288 	memput(rule, sizeof *rule);
289 	return (next);
290 }
291 
292 static int
293 add_rule(struct gen_p *irs,
294 	 enum irs_map_id map, enum irs_acc_id acc,
295 	 const char *options)
296 {
297 	struct irs_rule **rules, *last, *tmp, *new;
298 	struct irs_inst *inst;
299 	const char *cp;
300 	int n;
301 
302 #ifndef WANT_IRS_GR
303 	if (map == irs_gr)
304 		return (-1);
305 #endif
306 #ifndef WANT_IRS_PW
307 	if (map == irs_pw)
308 		return (-1);
309 #endif
310 #ifndef WANT_IRS_NIS
311 	if (acc == irs_nis)
312 		return (-1);
313 #endif
314 	new = memget(sizeof *new);
315 	if (new == NULL)
316 		return (-1);
317 	memset(new, 0x5e, sizeof *new);
318 	new->next = NULL;
319 
320 	new->inst = &irs->accessors[acc];
321 
322 	new->flags = 0;
323 	cp = options;
324 	while (cp && *cp) {
325 		char option[50], *next;
326 
327 		next = strchr(cp, ',');
328 		if (next)
329 			n = next++ - cp;
330 		else
331 			n = strlen(cp);
332 		if ((size_t)n > sizeof option - 1)
333 			n = sizeof option - 1;
334 		strncpy(option, cp, n);
335 		option[n] = '\0';
336 
337 		n = find_name(option, option_names);
338 		if (n >= 0)
339 			new->flags |= n;
340 
341 		cp = next;
342 	}
343 
344 	rules = &irs->map_rules[map];
345 	for (last = NULL, tmp = *rules;
346 	     tmp != NULL;
347 	     last = tmp, tmp = tmp->next)
348 		(void)NULL;
349 	if (last == NULL)
350 		*rules = new;
351 	else
352 		last->next = new;
353 
354 	/* Try to instantiate map accessors for this if necessary & approp. */
355 	inst = &irs->accessors[acc];
356 	if (inst->acc == NULL && accs[acc] != NULL)
357 		inst->acc = (*accs[acc])(irs->options);
358 	if (inst->acc != NULL) {
359 		if (inst->gr == NULL && inst->acc->gr_map != NULL)
360 			inst->gr = (*inst->acc->gr_map)(inst->acc);
361 		if (inst->pw == NULL && inst->acc->pw_map != NULL)
362 			inst->pw = (*inst->acc->pw_map)(inst->acc);
363 		if (inst->sv == NULL && inst->acc->sv_map != NULL)
364 			inst->sv = (*inst->acc->sv_map)(inst->acc);
365 		if (inst->pr == NULL && inst->acc->pr_map != NULL)
366 			inst->pr = (*inst->acc->pr_map)(inst->acc);
367 		if (inst->ho == NULL && inst->acc->ho_map != NULL)
368 			inst->ho = (*inst->acc->ho_map)(inst->acc);
369 		if (inst->nw == NULL && inst->acc->nw_map != NULL)
370 			inst->nw = (*inst->acc->nw_map)(inst->acc);
371 		if (inst->ng == NULL && inst->acc->ng_map != NULL)
372 			inst->ng = (*inst->acc->ng_map)(inst->acc);
373 	}
374 
375 	return (0);
376 }
377 
378 static void
379 default_map_rules(struct gen_p *irs) {
380 	/* Install time honoured and proved BSD style rules as default. */
381 	add_rule(irs, irs_gr, irs_lcl, "");
382 	add_rule(irs, irs_pw, irs_lcl, "");
383 	add_rule(irs, irs_sv, irs_lcl, "");
384 	add_rule(irs, irs_pr, irs_lcl, "");
385 #ifdef SUNW_HOSTS_FALLBACK
386 	if (__res_no_hosts_fallback())
387 		add_rule(irs, irs_ho, irs_dns, "");
388 	else {
389 		add_rule(irs, irs_ho, irs_dns, "continue");
390 		add_rule(irs, irs_ho, irs_lcl, "");
391 	}
392 #else  /* SUNW_HOSTS_FALLBACK */
393 	add_rule(irs, irs_ho, irs_dns, "continue");
394 	add_rule(irs, irs_ho, irs_lcl, "");
395 #endif /* SUNW_HOSTS_FALLBACK */
396 	add_rule(irs, irs_nw, irs_dns, "continue");
397 	add_rule(irs, irs_nw, irs_lcl, "");
398 	add_rule(irs, irs_ng, irs_lcl, "");
399 }
400 
401 static void
402 init_map_rules(struct gen_p *irs, const char *conf_file) {
403 	char line[1024], pattern[40], mapname[20], accname[20], options[100];
404 	FILE *conf;
405 
406 #ifdef SUNW_HOSTS_FALLBACK
407 	if (__res_no_hosts_fallback()) {
408 		default_map_rules(irs);
409 		return;
410 	}
411 #endif /* SUNW_HOSTS_FALLBACK */
412 
413 	if (conf_file == NULL)
414 		conf_file = _PATH_IRS_CONF ;
415 
416 	/* A conf file of "" means compiled in defaults. Irpd wants this */
417 	if (conf_file[0] == '\0' || (conf = fopen(conf_file, "r")) == NULL) {
418 		default_map_rules(irs);
419 		return;
420 	}
421 	(void) sprintf(pattern, "%%%ds %%%ds %%%ds\n",
422 		       sizeof mapname, sizeof accname, sizeof options);
423 	while (fgets(line, sizeof line, conf)) {
424 		enum irs_map_id map;
425 		enum irs_acc_id acc;
426 		char *tmp;
427 		int n;
428 
429 		for (tmp = line;
430 		     isascii((unsigned char)*tmp) &&
431 		     isspace((unsigned char)*tmp);
432 		     tmp++)
433 			(void)NULL;
434 		if (*tmp == '#' || *tmp == '\n' || *tmp == '\0')
435 			continue;
436 		n = sscanf(tmp, pattern, mapname, accname, options);
437 		if (n < 2)
438 			continue;
439 		if (n < 3)
440 			options[0] = '\0';
441 
442 		n = find_name(mapname, map_names);
443 		INSIST(n < irs_nmap);
444 		if (n < 0)
445 			continue;
446 		map = (enum irs_map_id) n;
447 
448 		n = find_name(accname, acc_names);
449 		INSIST(n < irs_nacc);
450 		if (n < 0)
451 			continue;
452 		acc = (enum irs_acc_id) n;
453 
454 		add_rule(irs, map, acc, options);
455 	}
456 	fclose(conf);
457 }
458