1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 2005 Apple Computer, Inc.
5 * All rights reserved.
6 *
7 * @APPLE_BSD_LICENSE_HEADER_START@
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 *
13 * 1.  Redistributions of source code must retain the above copyright
14 *     notice, this list of conditions and the following disclaimer.
15 * 2.  Redistributions in binary form must reproduce the above copyright
16 *     notice, this list of conditions and the following disclaimer in the
17 *     documentation and/or other materials provided with the distribution.
18 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
19 *     its contributors may be used to endorse or promote products derived
20 *     from this software without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
23 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
24 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
25 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
26 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
27 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
29 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 *
33 * @APPLE_BSD_LICENSE_HEADER_END@
34 */
35
36#include <sys/cdefs.h>
37__FBSDID("$FreeBSD$");
38
39#include <sys/types.h>
40
41#include <bsm/libbsm.h>
42#include <bsm/audit_uevents.h>
43
44#include <err.h>
45#include <errno.h>
46#include <pwd.h>
47#include <stdio.h>
48#include <strings.h>
49#include <unistd.h>
50
51#include "login.h"
52
53/*
54 * Audit data
55 */
56static au_tid_t tid;
57
58/*
59 * The following tokens are included in the audit record for a successful
60 * login: header, subject, return.
61 */
62void
63au_login_success(void)
64{
65	token_t *tok;
66	int aufd;
67	au_mask_t aumask;
68	auditinfo_t auinfo;
69	uid_t uid = pwd->pw_uid;
70	gid_t gid = pwd->pw_gid;
71	pid_t pid = getpid();
72	int au_cond;
73
74	/* If we are not auditing, don't cut an audit record; just return. */
75 	if (auditon(A_GETCOND, &au_cond, sizeof(au_cond)) < 0) {
76		if (errno == ENOSYS)
77			return;
78		errx(1, "could not determine audit condition");
79	}
80	if (au_cond == AUC_NOAUDIT)
81		return;
82
83	/* Compute and set the user's preselection mask. */
84	if (au_user_mask(pwd->pw_name, &aumask) == -1)
85		errx(1, "could not calculate audit mask");
86
87	/* Set the audit info for the user. */
88	auinfo.ai_auid = uid;
89	auinfo.ai_asid = pid;
90	bcopy(&tid, &auinfo.ai_termid, sizeof(auinfo.ai_termid));
91	bcopy(&aumask, &auinfo.ai_mask, sizeof(auinfo.ai_mask));
92	if (setaudit(&auinfo) != 0)
93		err(1, "setaudit failed");
94
95	if ((aufd = au_open()) == -1)
96		errx(1, "audit error: au_open() failed");
97
98	if ((tok = au_to_subject32(uid, geteuid(), getegid(), uid, gid, pid,
99	    pid, &tid)) == NULL)
100		errx(1, "audit error: au_to_subject32() failed");
101	au_write(aufd, tok);
102
103	if ((tok = au_to_return32(0, 0)) == NULL)
104		errx(1, "audit error: au_to_return32() failed");
105	au_write(aufd, tok);
106
107	if (au_close(aufd, 1, AUE_login) == -1)
108		errx(1, "audit record was not committed.");
109}
110
111/*
112 * The following tokens are included in the audit record for failed
113 * login attempts: header, subject, text, return.
114 */
115void
116au_login_fail(const char *errmsg, int na)
117{
118	token_t *tok;
119	int aufd;
120	int au_cond;
121	uid_t uid;
122	gid_t gid;
123	pid_t pid = getpid();
124
125	/* If we are not auditing, don't cut an audit record; just return. */
126 	if (auditon(A_GETCOND, &au_cond, sizeof(au_cond)) < 0) {
127		if (errno == ENOSYS)
128			return;
129		errx(1, "could not determine audit condition");
130	}
131	if (au_cond == AUC_NOAUDIT)
132		return;
133
134	if ((aufd = au_open()) == -1)
135		errx(1, "audit error: au_open() failed");
136
137	if (na) {
138		/*
139		 * Non attributable event.  Assuming that login is not called
140		 * within a user's session => auid,asid == -1.
141		 */
142		if ((tok = au_to_subject32(-1, geteuid(), getegid(), -1, -1,
143		    pid, -1, &tid)) == NULL)
144			errx(1, "audit error: au_to_subject32() failed");
145	} else {
146		/* We know the subject -- so use its value instead. */
147		uid = pwd->pw_uid;
148		gid = pwd->pw_gid;
149		if ((tok = au_to_subject32(uid, geteuid(), getegid(), uid,
150		    gid, pid, pid, &tid)) == NULL)
151			errx(1, "audit error: au_to_subject32() failed");
152	}
153	au_write(aufd, tok);
154
155	/* Include the error message. */
156	if ((tok = au_to_text(errmsg)) == NULL)
157		errx(1, "audit error: au_to_text() failed");
158	au_write(aufd, tok);
159
160	if ((tok = au_to_return32(1, errno)) == NULL)
161		errx(1, "audit error: au_to_return32() failed");
162	au_write(aufd, tok);
163
164	if (au_close(aufd, 1, AUE_login) == -1)
165		errx(1, "audit error: au_close() was not committed");
166}
167
168/*
169 * The following tokens are included in the audit record for a logout:
170 * header, subject, return.
171 */
172void
173audit_logout(void)
174{
175	token_t *tok;
176	int aufd;
177	uid_t uid = pwd->pw_uid;
178	gid_t gid = pwd->pw_gid;
179	pid_t pid = getpid();
180	int au_cond;
181
182	/* If we are not auditing, don't cut an audit record; just return. */
183 	if (auditon(A_GETCOND, &au_cond, sizeof(int)) < 0) {
184		if (errno == ENOSYS)
185			return;
186		errx(1, "could not determine audit condition");
187	}
188	if (au_cond == AUC_NOAUDIT)
189		return;
190
191	if ((aufd = au_open()) == -1)
192		errx(1, "audit error: au_open() failed");
193
194	/* The subject that is created (euid, egid of the current process). */
195	if ((tok = au_to_subject32(uid, geteuid(), getegid(), uid, gid, pid,
196	    pid, &tid)) == NULL)
197		errx(1, "audit error: au_to_subject32() failed");
198	au_write(aufd, tok);
199
200	if ((tok = au_to_return32(0, 0)) == NULL)
201		errx(1, "audit error: au_to_return32() failed");
202	au_write(aufd, tok);
203
204	if (au_close(aufd, 1, AUE_logout) == -1)
205		errx(1, "audit record was not committed.");
206}
207