audit.c revision 323134 
1/*
2 * Copyright (c) 2004, 2005 Darren Tucker.  All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
14 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
15 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
16 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
17 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
18 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
19 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
20 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
22 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23 */
24
25#include "includes.h"
26
27#include <stdarg.h>
28#include <string.h>
29
30#ifdef SSH_AUDIT_EVENTS
31
32#include "audit.h"
33#include "log.h"
34#include "key.h"
35#include "hostfile.h"
36#include "auth.h"
37
38/*
39 * Care must be taken when using this since it WILL NOT be initialized when
40 * audit_connection_from() is called and MAY NOT be initialized when
41 * audit_event(CONNECTION_ABANDON) is called.  Test for NULL before using.
42 */
43extern Authctxt *the_authctxt;
44
45/* Maybe add the audit class to struct Authmethod? */
46ssh_audit_event_t
47audit_classify_auth(const char *method)
48{
49	if (strcmp(method, "none") == 0)
50		return SSH_AUTH_FAIL_NONE;
51	else if (strcmp(method, "password") == 0)
52		return SSH_AUTH_FAIL_PASSWD;
53	else if (strcmp(method, "publickey") == 0 ||
54	    strcmp(method, "rsa") == 0)
55		return SSH_AUTH_FAIL_PUBKEY;
56	else if (strncmp(method, "keyboard-interactive", 20) == 0 ||
57	    strcmp(method, "challenge-response") == 0)
58		return SSH_AUTH_FAIL_KBDINT;
59	else if (strcmp(method, "hostbased") == 0 ||
60	    strcmp(method, "rhosts-rsa") == 0)
61		return SSH_AUTH_FAIL_HOSTBASED;
62	else if (strcmp(method, "gssapi-with-mic") == 0)
63		return SSH_AUTH_FAIL_GSSAPI;
64	else
65		return SSH_AUDIT_UNKNOWN;
66}
67
68/* helper to return supplied username */
69const char *
70audit_username(void)
71{
72	static const char unknownuser[] = "(unknown user)";
73	static const char invaliduser[] = "(invalid user)";
74
75	if (the_authctxt == NULL || the_authctxt->user == NULL)
76		return (unknownuser);
77	if (!the_authctxt->valid)
78		return (invaliduser);
79	return (the_authctxt->user);
80}
81
82const char *
83audit_event_lookup(ssh_audit_event_t ev)
84{
85	int i;
86	static struct event_lookup_struct {
87		ssh_audit_event_t event;
88		const char *name;
89	} event_lookup[] = {
90		{SSH_LOGIN_EXCEED_MAXTRIES,	"LOGIN_EXCEED_MAXTRIES"},
91		{SSH_LOGIN_ROOT_DENIED,		"LOGIN_ROOT_DENIED"},
92		{SSH_AUTH_SUCCESS,		"AUTH_SUCCESS"},
93		{SSH_AUTH_FAIL_NONE,		"AUTH_FAIL_NONE"},
94		{SSH_AUTH_FAIL_PASSWD,		"AUTH_FAIL_PASSWD"},
95		{SSH_AUTH_FAIL_KBDINT,		"AUTH_FAIL_KBDINT"},
96		{SSH_AUTH_FAIL_PUBKEY,		"AUTH_FAIL_PUBKEY"},
97		{SSH_AUTH_FAIL_HOSTBASED,	"AUTH_FAIL_HOSTBASED"},
98		{SSH_AUTH_FAIL_GSSAPI,		"AUTH_FAIL_GSSAPI"},
99		{SSH_INVALID_USER,		"INVALID_USER"},
100		{SSH_NOLOGIN,			"NOLOGIN"},
101		{SSH_CONNECTION_CLOSE,		"CONNECTION_CLOSE"},
102		{SSH_CONNECTION_ABANDON,	"CONNECTION_ABANDON"},
103		{SSH_AUDIT_UNKNOWN,		"AUDIT_UNKNOWN"}
104	};
105
106	for (i = 0; event_lookup[i].event != SSH_AUDIT_UNKNOWN; i++)
107		if (event_lookup[i].event == ev)
108			break;
109	return(event_lookup[i].name);
110}
111
112# ifndef CUSTOM_SSH_AUDIT_EVENTS
113/*
114 * Null implementations of audit functions.
115 * These get used if SSH_AUDIT_EVENTS is defined but no audit module is enabled.
116 */
117
118/*
119 * Called after a connection has been accepted but before any authentication
120 * has been attempted.
121 */
122void
123audit_connection_from(const char *host, int port)
124{
125	debug("audit connection from %s port %d euid %d", host, port,
126	    (int)geteuid());
127}
128
129/*
130 * Called when various events occur (see audit.h for a list of possible
131 * events and what they mean).
132 */
133void
134audit_event(ssh_audit_event_t event)
135{
136	debug("audit event euid %d user %s event %d (%s)", geteuid(),
137	    audit_username(), event, audit_event_lookup(event));
138}
139
140/*
141 * Called when a user session is started.  Argument is the tty allocated to
142 * the session, or NULL if no tty was allocated.
143 *
144 * Note that this may be called multiple times if multiple sessions are used
145 * within a single connection.
146 */
147void
148audit_session_open(struct logininfo *li)
149{
150	const char *t = li->line ? li->line : "(no tty)";
151
152	debug("audit session open euid %d user %s tty name %s", geteuid(),
153	    audit_username(), t);
154}
155
156/*
157 * Called when a user session is closed.  Argument is the tty allocated to
158 * the session, or NULL if no tty was allocated.
159 *
160 * Note that this may be called multiple times if multiple sessions are used
161 * within a single connection.
162 */
163void
164audit_session_close(struct logininfo *li)
165{
166	const char *t = li->line ? li->line : "(no tty)";
167
168	debug("audit session close euid %d user %s tty name %s", geteuid(),
169	    audit_username(), t);
170}
171
172/*
173 * This will be called when a user runs a non-interactive command.  Note that
174 * it may be called multiple times for a single connection since SSH2 allows
175 * multiple sessions within a single connection.
176 */
177void
178audit_run_command(const char *command)
179{
180	debug("audit run command euid %d user %s command '%.200s'", geteuid(),
181	    audit_username(), command);
182}
183# endif  /* !defined CUSTOM_SSH_AUDIT_EVENTS */
184#endif /* SSH_AUDIT_EVENTS */
185