xref: /freebsd/contrib/openpam/lib/libpam/openpam_set_option.c (revision 389e4940069316fe667ffa263fa7d6390d0a960f)
1 /*-
2  * Copyright (c) 2002-2003 Networks Associates Technology, Inc.
3  * Copyright (c) 2004-2011 Dag-Erling Smørgrav
4  * All rights reserved.
5  *
6  * This software was developed for the FreeBSD Project by ThinkSec AS and
7  * Network Associates Laboratories, the Security Research Division of
8  * Network Associates, Inc.  under DARPA/SPAWAR contract N66001-01-C-8035
9  * ("CBOSS"), as part of the DARPA CHATS research program.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. The name of the author may not be used to endorse or promote
20  *    products derived from this software without specific prior written
21  *    permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  * $OpenPAM: openpam_set_option.c 938 2017-04-30 21:34:42Z des $
36  */
37 
38 #ifdef HAVE_CONFIG_H
39 # include "config.h"
40 #endif
41 
42 #include <sys/param.h>
43 
44 #include <stdio.h>
45 #include <stdlib.h>
46 #include <string.h>
47 
48 #include <security/pam_appl.h>
49 
50 #include "openpam_impl.h"
51 #include "openpam_asprintf.h"
52 
53 /*
54  * OpenPAM extension
55  *
56  * Sets the value of a module option
57  */
58 
59 int
60 openpam_set_option(pam_handle_t *pamh,
61 	const char *option,
62 	const char *value)
63 {
64 	pam_chain_t *cur;
65 	char *opt, **optv;
66 	size_t len;
67 	int i;
68 
69 	ENTERS(option);
70 	if (pamh == NULL || pamh->current == NULL || option == NULL)
71 		RETURNC(PAM_SYSTEM_ERR);
72 	cur = pamh->current;
73 	for (len = 0; option[len] != '\0'; ++len)
74 		if (option[len] == '=')
75 			break;
76 	for (i = 0; i < cur->optc; ++i) {
77 		if (strncmp(cur->optv[i], option, len) == 0 &&
78 		    (cur->optv[i][len] == '\0' || cur->optv[i][len] == '='))
79 			break;
80 	}
81 	if (value == NULL) {
82 		/* remove */
83 		if (i == cur->optc)
84 			RETURNC(PAM_SUCCESS);
85 		for (free(cur->optv[i]); i < cur->optc; ++i)
86 			cur->optv[i] = cur->optv[i + 1];
87 		cur->optv[i] = NULL;
88 		RETURNC(PAM_SUCCESS);
89 	}
90 	if (asprintf(&opt, "%.*s=%s", (int)len, option, value) < 0)
91 		RETURNC(PAM_BUF_ERR);
92 	if (i == cur->optc) {
93 		/* add */
94 		optv = realloc(cur->optv, sizeof(char *) * (cur->optc + 2));
95 		if (optv == NULL) {
96 			FREE(opt);
97 			RETURNC(PAM_BUF_ERR);
98 		}
99 		optv[i] = opt;
100 		optv[i + 1] = NULL;
101 		cur->optv = optv;
102 		++cur->optc;
103 	} else {
104 		/* replace */
105 		FREE(cur->optv[i]);
106 		cur->optv[i] = opt;
107 	}
108 	RETURNC(PAM_SUCCESS);
109 }
110 
111 /*
112  * Error codes:
113  *
114  *	PAM_SYSTEM_ERR
115  *	PAM_BUF_ERR
116  */
117 
118 /**
119  * The =openpam_set_option function sets the specified option in the
120  * context of the currently executing service module.
121  *
122  * >openpam_get_option
123  */
124