xref: /netbsd-src/external/bsd/openpam/dist/lib/libpam/pam_start.c (revision 0d9d0fd8a30be9a1924e715bbcf67a4a83efd262)
1 /*	$NetBSD: pam_start.c,v 1.4 2023/06/30 21:46:21 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 2002-2003 Networks Associates Technology, Inc.
5  * Copyright (c) 2004-2011 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: pam_start.c,v 1.4 2023/06/30 21:46:21 christos Exp $");
44 
45 #include <stdlib.h>
46 #include <string.h>
47 #include <unistd.h>
48 
49 #include <security/pam_appl.h>
50 
51 #include "openpam_impl.h"
52 #include "openpam_strlcpy.h"
53 
54 
55 /*
56  * XSSO 4.2.1
57  * XSSO 6 page 89
58  *
59  * Initiate a PAM transaction
60  */
61 
62 int
pam_start(const char * service,const char * user,const struct pam_conv * pam_conv,pam_handle_t ** pamh)63 pam_start(const char *service,
64 	const char *user,
65 	const struct pam_conv *pam_conv,
66 	pam_handle_t **pamh)
67 {
68 	char *hostname = NULL;
69 	struct pam_handle *ph;
70 	int r;
71 	size_t hostname_size;
72 	long h;
73 
74 #ifdef _SC_HOST_NAME_MAX
75 	h = sysconf(_SC_HOST_NAME_MAX);
76 #else
77 	h = -1;
78 #endif
79 	hostname_size = (size_t)(h < 10 ? 1024 : h) + 1;
80 
81 	ENTER();
82 	if ((ph = calloc((size_t)1, sizeof *ph)) == NULL)
83 		RETURNC(PAM_BUF_ERR);
84 	if ((r = pam_set_item(ph, PAM_SERVICE, service)) != PAM_SUCCESS)
85 		goto fail;
86 	if ((hostname = malloc(hostname_size)) == NULL)
87 		goto fail;
88 	if (gethostname(hostname, hostname_size) != 0)
89 		strlcpy(hostname, "localhost", hostname_size);
90 	if ((r = pam_set_item(ph, PAM_HOST, hostname)) != PAM_SUCCESS)
91 		goto fail;
92 	if ((r = pam_set_item(ph, PAM_USER, user)) != PAM_SUCCESS)
93 		goto fail;
94 	if ((r = pam_set_item(ph, PAM_CONV, pam_conv)) != PAM_SUCCESS)
95 		goto fail;
96 	if ((r = openpam_configure(ph, service)) != PAM_SUCCESS)
97 		goto fail;
98 	free(hostname);
99 	*pamh = ph;
100 	openpam_log(PAM_LOG_DEBUG, "pam_start(\"%s\") succeeded", service);
101 	RETURNC(PAM_SUCCESS);
102 fail:
103 	free(hostname);
104 	pam_end(ph, r);
105 	RETURNC(r);
106 }
107 
108 /*
109  * Error codes:
110  *
111  *	=openpam_configure
112  *	=pam_set_item
113  *	!PAM_SYMBOL_ERR
114  *	PAM_BUF_ERR
115  */
116 
117 /**
118  * The =pam_start function creates and initializes a PAM context.
119  *
120  * The =service argument specifies the name of the policy to apply, and is
121  * stored in the =PAM_SERVICE item in the created context.
122  *
123  * The =user argument specifies the name of the target user - the user the
124  * created context will serve to authenticate.
125  * It is stored in the =PAM_USER item in the created context.
126  *
127  * The =pam_conv argument points to a =struct pam_conv describing the
128  * conversation function to use; see =pam_conv for details.
129  *
130  * >pam_get_item
131  * >pam_set_item
132  * >pam_end
133  */
134