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