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)
21static 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
33static 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
62struct 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
82static struct group *	gr_next(struct irs_gr *);
83static struct group *	gr_byname(struct irs_gr *, const char *);
84static struct group *	gr_bygid(struct irs_gr *, gid_t);
85static void		gr_rewind(struct irs_gr *);
86static void		gr_close(struct irs_gr *);
87static int		gr_list(struct irs_gr *, const char *,
88				gid_t, gid_t *, int *);
89static void		gr_minimize(struct irs_gr *);
90static struct __res_state * gr_res_get(struct irs_gr *);
91static void		gr_res_set(struct irs_gr *,
92				   struct __res_state *,
93				   void (*)(void *));
94
95static struct group *	get_hes_group(struct irs_gr *this,
96				      const char *name,
97				      const char *type);
98
99/* Public. */
100
101struct irs_gr *
102irs_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
138static void
139gr_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
150static struct group *
151gr_next(struct irs_gr *this) {
152
153	UNUSED(this);
154
155	return (NULL);
156}
157
158static struct group *
159gr_byname(struct irs_gr *this, const char *name) {
160	return (get_hes_group(this, name, "group"));
161}
162
163static struct group *
164gr_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
171static void
172gr_rewind(struct irs_gr *this) {
173
174	UNUSED(this);
175
176	/* NOOP */
177}
178
179static int
180gr_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
193static void
194gr_minimize(struct irs_gr *this) {
195
196	UNUSED(this);
197	/* NOOP */
198}
199
200/* Private. */
201
202static struct group *
203get_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
279static struct __res_state *
280gr_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
287static void
288gr_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