audit-linux.c revision 323129 
1/* $Id: audit-linux.c,v 1.1 2011/01/17 10:15:30 dtucker Exp $ */
2
3/*
4 * Copyright 2010 Red Hat, Inc.  All rights reserved.
5 * Use is subject to license terms.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 *
27 * Red Hat author: Jan F. Chadima <jchadima@redhat.com>
28 */
29
30#include "includes.h"
31#if defined(USE_LINUX_AUDIT)
32#include <libaudit.h>
33#include <unistd.h>
34#include <string.h>
35
36#include "log.h"
37#include "audit.h"
38#include "canohost.h"
39#include "packet.h"
40
41const char *audit_username(void);
42
43int
44linux_audit_record_event(int uid, const char *username, const char *hostname,
45    const char *ip, const char *ttyn, int success)
46{
47	int audit_fd, rc, saved_errno;
48
49	if ((audit_fd = audit_open()) < 0) {
50		if (errno == EINVAL || errno == EPROTONOSUPPORT ||
51		    errno == EAFNOSUPPORT)
52			return 1; /* No audit support in kernel */
53		else
54			return 0; /* Must prevent login */
55	}
56	rc = audit_log_acct_message(audit_fd, AUDIT_USER_LOGIN,
57	    NULL, "login", username ? username : "(unknown)",
58	    username == NULL ? uid : -1, hostname, ip, ttyn, success);
59	saved_errno = errno;
60	close(audit_fd);
61
62	/*
63	 * Do not report error if the error is EPERM and sshd is run as non
64	 * root user.
65	 */
66	if ((rc == -EPERM) && (geteuid() != 0))
67		rc = 0;
68	errno = saved_errno;
69
70	return rc >= 0;
71}
72
73/* Below is the sshd audit API code */
74
75void
76audit_connection_from(const char *host, int port)
77{
78	/* not implemented */
79}
80
81void
82audit_run_command(const char *command)
83{
84	/* not implemented */
85}
86
87void
88audit_session_open(struct logininfo *li)
89{
90	if (linux_audit_record_event(li->uid, NULL, li->hostname, NULL,
91	    li->line, 1) == 0)
92		fatal("linux_audit_write_entry failed: %s", strerror(errno));
93}
94
95void
96audit_session_close(struct logininfo *li)
97{
98	/* not implemented */
99}
100
101void
102audit_event(ssh_audit_event_t event)
103{
104	struct ssh *ssh = active_state; /* XXX */
105
106	switch(event) {
107	case SSH_AUTH_SUCCESS:
108	case SSH_CONNECTION_CLOSE:
109	case SSH_NOLOGIN:
110	case SSH_LOGIN_EXCEED_MAXTRIES:
111	case SSH_LOGIN_ROOT_DENIED:
112		break;
113	case SSH_AUTH_FAIL_NONE:
114	case SSH_AUTH_FAIL_PASSWD:
115	case SSH_AUTH_FAIL_KBDINT:
116	case SSH_AUTH_FAIL_PUBKEY:
117	case SSH_AUTH_FAIL_HOSTBASED:
118	case SSH_AUTH_FAIL_GSSAPI:
119	case SSH_INVALID_USER:
120		linux_audit_record_event(-1, audit_username(), NULL,
121		    ssh_remote_ipaddr(ssh), "sshd", 0);
122		break;
123	default:
124		debug("%s: unhandled event %d", __func__, event);
125		break;
126	}
127}
128#endif /* USE_LINUX_AUDIT */
129