xref: /netbsd-src/external/bsd/openpam/dist/lib/libpam/openpam_set_option.c (revision 0d9d0fd8a30be9a1924e715bbcf67a4a83efd262)
1 /*	$NetBSD: openpam_set_option.c,v 1.4 2023/06/30 21:46:20 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 2002-2003 Networks Associates Technology, Inc.
5  * Copyright (c) 2004-2023 Dag-Erling Smørgrav
6  * All rights reserved.
7  *
8  * This software was developed for the FreeBSD Project by ThinkSec AS and
9  * Network Associates Laboratories, the Security Research Division of
10  * Network Associates, Inc.  under DARPA/SPAWAR contract N66001-01-C-8035
11  * ("CBOSS"), as part of the DARPA CHATS research program.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  * 3. The name of the author may not be used to endorse or promote
22  *    products derived from this software without specific prior written
23  *    permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  */
37 
38 #ifdef HAVE_CONFIG_H
39 # include "config.h"
40 #endif
41 
42 #include <sys/cdefs.h>
43 __RCSID("$NetBSD: openpam_set_option.c,v 1.4 2023/06/30 21:46:20 christos Exp $");
44 
45 #include <sys/param.h>
46 
47 #include <stdio.h>
48 #include <stdlib.h>
49 #include <string.h>
50 
51 #include <security/pam_appl.h>
52 
53 #include "openpam_impl.h"
54 #include "openpam_asprintf.h"
55 
56 /*
57  * OpenPAM extension
58  *
59  * Sets the value of a module option
60  */
61 
62 int
openpam_set_option(pam_handle_t * pamh,const char * option,const char * value)63 openpam_set_option(pam_handle_t *pamh,
64 	const char *option,
65 	const char *value)
66 {
67 	pam_chain_t *cur;
68 	char *opt, **optv;
69 	size_t len;
70 	int i;
71 
72 	ENTERS(option);
73 	if (pamh == NULL || pamh->current == NULL || option == NULL)
74 		RETURNC(PAM_SYSTEM_ERR);
75 	cur = pamh->current;
76 	for (len = 0; option[len] != '\0'; ++len)
77 		if (option[len] == '=')
78 			break;
79 	for (i = 0; i < cur->optc; ++i) {
80 		if (strncmp(cur->optv[i], option, len) == 0 &&
81 		    (cur->optv[i][len] == '\0' || cur->optv[i][len] == '='))
82 			break;
83 	}
84 	if (value == NULL) {
85 		/* remove */
86 		if (i == cur->optc)
87 			RETURNC(PAM_SUCCESS);
88 		for (free(cur->optv[i]); i < cur->optc; ++i)
89 			cur->optv[i] = cur->optv[i + 1];
90 		cur->optv[i] = NULL;
91 		--cur->optc;
92 		RETURNC(PAM_SUCCESS);
93 	}
94 	if (asprintf(&opt, "%.*s=%s", (int)len, option, value) < 0)
95 		RETURNC(PAM_BUF_ERR);
96 	if (i == cur->optc) {
97 		/* add */
98 		optv = realloc(cur->optv,
99 		    sizeof(*optv) * ((size_t)cur->optc + 2));
100 		if (optv == NULL) {
101 			FREE(opt);
102 			RETURNC(PAM_BUF_ERR);
103 		}
104 		optv[i] = opt;
105 		optv[i + 1] = NULL;
106 		cur->optv = optv;
107 		++cur->optc;
108 	} else {
109 		/* replace */
110 		FREE(cur->optv[i]);
111 		cur->optv[i] = opt;
112 	}
113 	RETURNC(PAM_SUCCESS);
114 }
115 
116 /*
117  * Error codes:
118  *
119  *	PAM_SYSTEM_ERR
120  *	PAM_BUF_ERR
121  */
122 
123 /**
124  * The =openpam_set_option function sets the specified option in the
125  * context of the currently executing service module.
126  *
127  * >openpam_get_option
128  */
129