audit-linux.c revision 323134 
1/*
2 * Copyright 2010 Red Hat, Inc.  All rights reserved.
3 * Use is subject to license terms.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 *
25 * Red Hat author: Jan F. Chadima <jchadima@redhat.com>
26 */
27
28#include "includes.h"
29#if defined(USE_LINUX_AUDIT)
30#include <libaudit.h>
31#include <unistd.h>
32#include <string.h>
33
34#include "log.h"
35#include "audit.h"
36#include "canohost.h"
37#include "packet.h"
38
39const char *audit_username(void);
40
41int
42linux_audit_record_event(int uid, const char *username, const char *hostname,
43    const char *ip, const char *ttyn, int success)
44{
45	int audit_fd, rc, saved_errno;
46
47	if ((audit_fd = audit_open()) < 0) {
48		if (errno == EINVAL || errno == EPROTONOSUPPORT ||
49		    errno == EAFNOSUPPORT)
50			return 1; /* No audit support in kernel */
51		else
52			return 0; /* Must prevent login */
53	}
54	rc = audit_log_acct_message(audit_fd, AUDIT_USER_LOGIN,
55	    NULL, "login", username ? username : "(unknown)",
56	    username == NULL ? uid : -1, hostname, ip, ttyn, success);
57	saved_errno = errno;
58	close(audit_fd);
59
60	/*
61	 * Do not report error if the error is EPERM and sshd is run as non
62	 * root user.
63	 */
64	if ((rc == -EPERM) && (geteuid() != 0))
65		rc = 0;
66	errno = saved_errno;
67
68	return rc >= 0;
69}
70
71/* Below is the sshd audit API code */
72
73void
74audit_connection_from(const char *host, int port)
75{
76	/* not implemented */
77}
78
79void
80audit_run_command(const char *command)
81{
82	/* not implemented */
83}
84
85void
86audit_session_open(struct logininfo *li)
87{
88	if (linux_audit_record_event(li->uid, NULL, li->hostname, NULL,
89	    li->line, 1) == 0)
90		fatal("linux_audit_write_entry failed: %s", strerror(errno));
91}
92
93void
94audit_session_close(struct logininfo *li)
95{
96	/* not implemented */
97}
98
99void
100audit_event(ssh_audit_event_t event)
101{
102	struct ssh *ssh = active_state; /* XXX */
103
104	switch(event) {
105	case SSH_AUTH_SUCCESS:
106	case SSH_CONNECTION_CLOSE:
107	case SSH_NOLOGIN:
108	case SSH_LOGIN_EXCEED_MAXTRIES:
109	case SSH_LOGIN_ROOT_DENIED:
110		break;
111	case SSH_AUTH_FAIL_NONE:
112	case SSH_AUTH_FAIL_PASSWD:
113	case SSH_AUTH_FAIL_KBDINT:
114	case SSH_AUTH_FAIL_PUBKEY:
115	case SSH_AUTH_FAIL_HOSTBASED:
116	case SSH_AUTH_FAIL_GSSAPI:
117	case SSH_INVALID_USER:
118		linux_audit_record_event(-1, audit_username(), NULL,
119		    ssh_remote_ipaddr(ssh), "sshd", 0);
120		break;
121	default:
122		debug("%s: unhandled event %d", __func__, event);
123		break;
124	}
125}
126#endif /* USE_LINUX_AUDIT */
127