xref: /freebsd/crypto/openssh/audit-linux.c (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
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 
41 const char *audit_username(void);
42 
43 int
44 linux_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 
75 void
76 audit_connection_from(const char *host, int port)
77 {
78 	/* not implemented */
79 }
80 
81 void
82 audit_run_command(const char *command)
83 {
84 	/* not implemented */
85 }
86 
87 void
88 audit_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 
95 void
96 audit_session_close(struct logininfo *li)
97 {
98 	/* not implemented */
99 }
100 
101 void
102 audit_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