xref: /netbsd-src/external/bsd/libbind/dist/irs/dns_gr.c (revision 5bbd2a12505d72a8177929a37b5cee489d0a1cfd)
1 /*	$NetBSD: dns_gr.c,v 1.1.1.2 2012/09/09 16:07:52 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
5  * Copyright (c) 1996-1999 by Internet Software Consortium.
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
17  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 
20 #if defined(LIBC_SCCS) && !defined(lint)
21 static const char rcsid[] = "Id: dns_gr.c,v 1.4 2005/04/27 04:56:21 sra Exp ";
22 #endif
23 
24 /*! \file
25  * \brief
26  * dns_gr.c --- this file contains the functions for accessing
27  * 	group information from Hesiod.
28  */
29 
30 #include "port_before.h"
31 
32 #ifndef WANT_IRS_GR
33 static int __bind_irs_gr_unneeded;
34 #else
35 
36 #include <sys/param.h>
37 #include <sys/types.h>
38 
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #include <errno.h>
43 #include <unistd.h>
44 
45 #include <sys/types.h>
46 #include <netinet/in.h>
47 #include <arpa/nameser.h>
48 #include <resolv.h>
49 
50 #include <isc/memcluster.h>
51 
52 #include <irs.h>
53 
54 #include "port_after.h"
55 
56 #include "irs_p.h"
57 #include "hesiod.h"
58 #include "dns_p.h"
59 
60 /* Types. */
61 
62 struct pvt {
63 	/*
64 	 * This is our private accessor data.  It has a shared hesiod context.
65 	 */
66 	struct dns_p *	dns;
67 	/*
68 	 * Need space to store the entries read from the group file.
69 	 * The members list also needs space per member, and the
70 	 * strings making up the user names must be allocated
71 	 * somewhere.  Rather than doing lots of small allocations,
72 	 * we keep one buffer and resize it as needed.
73 	 */
74 	struct group	group;
75 	size_t		nmemb;		/*%< Malloc'd max index of gr_mem[]. */
76 	char *		membuf;
77 	size_t		membufsize;
78 };
79 
80 /* Forward. */
81 
82 static struct group *	gr_next(struct irs_gr *);
83 static struct group *	gr_byname(struct irs_gr *, const char *);
84 static struct group *	gr_bygid(struct irs_gr *, gid_t);
85 static void		gr_rewind(struct irs_gr *);
86 static void		gr_close(struct irs_gr *);
87 static int		gr_list(struct irs_gr *, const char *,
88 				gid_t, gid_t *, int *);
89 static void		gr_minimize(struct irs_gr *);
90 static struct __res_state * gr_res_get(struct irs_gr *);
91 static void		gr_res_set(struct irs_gr *,
92 				   struct __res_state *,
93 				   void (*)(void *));
94 
95 static struct group *	get_hes_group(struct irs_gr *this,
96 				      const char *name,
97 				      const char *type);
98 
99 /* Public. */
100 
101 struct irs_gr *
irs_dns_gr(struct irs_acc * this)102 irs_dns_gr(struct irs_acc *this) {
103 	struct dns_p *dns = (struct dns_p *)this->private;
104 	struct irs_gr *gr;
105 	struct pvt *pvt;
106 
107 	if (!dns || !dns->hes_ctx) {
108 		errno = ENODEV;
109 		return (NULL);
110 	}
111 	if (!(pvt = memget(sizeof *pvt))) {
112 		errno = ENOMEM;
113 		return (NULL);
114 	}
115 	memset(pvt, 0, sizeof *pvt);
116 	pvt->dns = dns;
117 	if (!(gr = memget(sizeof *gr))) {
118 		memput(pvt, sizeof *pvt);
119 		errno = ENOMEM;
120 		return (NULL);
121 	}
122 	memset(gr, 0x5e, sizeof *gr);
123 	gr->private = pvt;
124 	gr->next = gr_next;
125 	gr->byname = gr_byname;
126 	gr->bygid = gr_bygid;
127 	gr->rewind = gr_rewind;
128 	gr->close = gr_close;
129 	gr->list = gr_list;
130 	gr->minimize = gr_minimize;
131 	gr->res_get = gr_res_get;
132 	gr->res_set = gr_res_set;
133 	return (gr);
134 }
135 
136 /* methods */
137 
138 static void
gr_close(struct irs_gr * this)139 gr_close(struct irs_gr *this) {
140 	struct pvt *pvt = (struct pvt *)this->private;
141 
142 	if (pvt->group.gr_mem)
143 		free(pvt->group.gr_mem);
144 	if (pvt->membuf)
145 		free(pvt->membuf);
146 	memput(pvt, sizeof *pvt);
147 	memput(this, sizeof *this);
148 }
149 
150 static struct group *
gr_next(struct irs_gr * this)151 gr_next(struct irs_gr *this) {
152 
153 	UNUSED(this);
154 
155 	return (NULL);
156 }
157 
158 static struct group *
gr_byname(struct irs_gr * this,const char * name)159 gr_byname(struct irs_gr *this, const char *name) {
160 	return (get_hes_group(this, name, "group"));
161 }
162 
163 static struct group *
gr_bygid(struct irs_gr * this,gid_t gid)164 gr_bygid(struct irs_gr *this, gid_t gid) {
165 	char name[32];
166 
167 	sprintf(name, "%ld", (long)gid);
168 	return (get_hes_group(this, name, "gid"));
169 }
170 
171 static void
gr_rewind(struct irs_gr * this)172 gr_rewind(struct irs_gr *this) {
173 
174 	UNUSED(this);
175 
176 	/* NOOP */
177 }
178 
179 static int
gr_list(struct irs_gr * this,const char * name,gid_t basegid,gid_t * groups,int * ngroups)180 gr_list(struct irs_gr *this, const char *name,
181 	gid_t basegid, gid_t *groups, int *ngroups)
182 {
183 	UNUSED(this);
184 	UNUSED(name);
185 	UNUSED(basegid);
186 	UNUSED(groups);
187 
188 	*ngroups = 0;
189 	/* There's some way to do this in Hesiod. */
190 	return (-1);
191 }
192 
193 static void
gr_minimize(struct irs_gr * this)194 gr_minimize(struct irs_gr *this) {
195 
196 	UNUSED(this);
197 	/* NOOP */
198 }
199 
200 /* Private. */
201 
202 static struct group *
get_hes_group(struct irs_gr * this,const char * name,const char * type)203 get_hes_group(struct irs_gr *this, const char *name, const char *type) {
204 	struct pvt *pvt = (struct pvt *)this->private;
205 	char **hes_list, *cp, **new;
206 	size_t num_members = 0;
207 	u_long t;
208 
209 	hes_list = hesiod_resolve(pvt->dns->hes_ctx, name, type);
210 	if (!hes_list)
211 		return (NULL);
212 
213 	/*
214 	 * Copy the returned hesiod string into storage space.
215 	 */
216 	if (pvt->membuf)
217 		free(pvt->membuf);
218 	pvt->membuf = strdup(*hes_list);
219 	hesiod_free_list(pvt->dns->hes_ctx, hes_list);
220 
221 	cp = pvt->membuf;
222 	pvt->group.gr_name = cp;
223 	if (!(cp = strchr(cp, ':')))
224 		goto cleanup;
225 	*cp++ = '\0';
226 
227 	pvt->group.gr_passwd = cp;
228 	if (!(cp = strchr(cp, ':')))
229 		goto cleanup;
230 	*cp++ = '\0';
231 
232 	errno = 0;
233 	t = strtoul(cp, NULL, 10);
234 	if (errno == ERANGE)
235 		goto cleanup;
236 	pvt->group.gr_gid = (gid_t) t;
237 	if (!(cp = strchr(cp, ':')))
238 		goto cleanup;
239 	cp++;
240 
241 	/*
242 	 * Parse the members out.
243 	 */
244 	while (*cp) {
245 		if (num_members+1 >= pvt->nmemb || pvt->group.gr_mem == NULL) {
246 			pvt->nmemb += 10;
247 			new = realloc(pvt->group.gr_mem,
248 				      pvt->nmemb * sizeof(char *));
249 			if (new == NULL)
250 				goto cleanup;
251 			pvt->group.gr_mem = new;
252 		}
253 		pvt->group.gr_mem[num_members++] = cp;
254 		if (!(cp = strchr(cp, ',')))
255 			break;
256 		*cp++ = '\0';
257 	}
258 	if (!pvt->group.gr_mem) {
259 		pvt->group.gr_mem = malloc(sizeof(char*));
260 		if (!pvt->group.gr_mem)
261 			goto cleanup;
262 	}
263 	pvt->group.gr_mem[num_members] = NULL;
264 
265 	return (&pvt->group);
266 
267  cleanup:
268 	if (pvt->group.gr_mem) {
269 		free(pvt->group.gr_mem);
270 		pvt->group.gr_mem = NULL;
271 	}
272 	if (pvt->membuf) {
273 		free(pvt->membuf);
274 		pvt->membuf = NULL;
275 	}
276 	return (NULL);
277 }
278 
279 static struct __res_state *
gr_res_get(struct irs_gr * this)280 gr_res_get(struct irs_gr *this) {
281 	struct pvt *pvt = (struct pvt *)this->private;
282 	struct dns_p *dns = pvt->dns;
283 
284 	return (__hesiod_res_get(dns->hes_ctx));
285 }
286 
287 static void
gr_res_set(struct irs_gr * this,struct __res_state * res,void (* free_res)(void *))288 gr_res_set(struct irs_gr *this, struct __res_state * res,
289 	   void (*free_res)(void *)) {
290 	struct pvt *pvt = (struct pvt *)this->private;
291 	struct dns_p *dns = pvt->dns;
292 
293 	__hesiod_res_set(dns->hes_ctx, res, free_res);
294 }
295 
296 #endif /* WANT_IRS_GR */
297