xref: /freebsd/crypto/openssh/audit.c (revision 87569f75a91f298c52a71823c04d41cf53c88889)
1 /* $Id: audit.c,v 1.3 2005/07/17 07:26:44 djm Exp $ */
2 
3 /*
4  * Copyright (c) 2004, 2005 Darren Tucker.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include "includes.h"
28 
29 #ifdef SSH_AUDIT_EVENTS
30 
31 #include "audit.h"
32 #include "log.h"
33 #include "auth.h"
34 
35 /*
36  * Care must be taken when using this since it WILL NOT be initialized when
37  * audit_connection_from() is called and MAY NOT be initialized when
38  * audit_event(CONNECTION_ABANDON) is called.  Test for NULL before using.
39  */
40 extern Authctxt *the_authctxt;
41 
42 /* Maybe add the audit class to struct Authmethod? */
43 ssh_audit_event_t
44 audit_classify_auth(const char *method)
45 {
46 	if (strcmp(method, "none") == 0)
47 		return SSH_AUTH_FAIL_NONE;
48 	else if (strcmp(method, "password") == 0)
49 		return SSH_AUTH_FAIL_PASSWD;
50 	else if (strcmp(method, "publickey") == 0 ||
51 	    strcmp(method, "rsa") == 0)
52 		return SSH_AUTH_FAIL_PUBKEY;
53 	else if (strncmp(method, "keyboard-interactive", 20) == 0 ||
54 	    strcmp(method, "challenge-response") == 0)
55 		return SSH_AUTH_FAIL_KBDINT;
56 	else if (strcmp(method, "hostbased") == 0 ||
57 	    strcmp(method, "rhosts-rsa") == 0)
58 		return SSH_AUTH_FAIL_HOSTBASED;
59 	else if (strcmp(method, "gssapi-with-mic") == 0)
60 		return SSH_AUTH_FAIL_GSSAPI;
61 	else
62 		return SSH_AUDIT_UNKNOWN;
63 }
64 
65 /* helper to return supplied username */
66 const char *
67 audit_username(void)
68 {
69 	static const char unknownuser[] = "(unknown user)";
70 	static const char invaliduser[] = "(invalid user)";
71 
72 	if (the_authctxt == NULL || the_authctxt->user == NULL)
73 		return (unknownuser);
74 	if (!the_authctxt->valid)
75 		return (invaliduser);
76 	return (the_authctxt->user);
77 }
78 
79 const char *
80 audit_event_lookup(ssh_audit_event_t ev)
81 {
82 	int i;
83 	static struct event_lookup_struct {
84 		ssh_audit_event_t event;
85 		const char *name;
86 	} event_lookup[] = {
87 		{SSH_LOGIN_EXCEED_MAXTRIES,	"LOGIN_EXCEED_MAXTRIES"},
88 		{SSH_LOGIN_ROOT_DENIED,		"LOGIN_ROOT_DENIED"},
89 		{SSH_AUTH_SUCCESS,		"AUTH_SUCCESS"},
90 		{SSH_AUTH_FAIL_NONE,		"AUTH_FAIL_NONE"},
91 		{SSH_AUTH_FAIL_PASSWD,		"AUTH_FAIL_PASSWD"},
92 		{SSH_AUTH_FAIL_KBDINT,		"AUTH_FAIL_KBDINT"},
93 		{SSH_AUTH_FAIL_PUBKEY,		"AUTH_FAIL_PUBKEY"},
94 		{SSH_AUTH_FAIL_HOSTBASED,	"AUTH_FAIL_HOSTBASED"},
95 		{SSH_AUTH_FAIL_GSSAPI,		"AUTH_FAIL_GSSAPI"},
96 		{SSH_INVALID_USER,		"INVALID_USER"},
97 		{SSH_NOLOGIN,			"NOLOGIN"},
98 		{SSH_CONNECTION_CLOSE,		"CONNECTION_CLOSE"},
99 		{SSH_CONNECTION_ABANDON,	"CONNECTION_ABANDON"},
100 		{SSH_AUDIT_UNKNOWN,		"AUDIT_UNKNOWN"}
101 	};
102 
103 	for (i = 0; event_lookup[i].event != SSH_AUDIT_UNKNOWN; i++)
104 		if (event_lookup[i].event == ev)
105 			break;
106 	return(event_lookup[i].name);
107 }
108 
109 # ifndef CUSTOM_SSH_AUDIT_EVENTS
110 /*
111  * Null implementations of audit functions.
112  * These get used if SSH_AUDIT_EVENTS is defined but no audit module is enabled.
113  */
114 
115 /*
116  * Called after a connection has been accepted but before any authentication
117  * has been attempted.
118  */
119 void
120 audit_connection_from(const char *host, int port)
121 {
122 	debug("audit connection from %s port %d euid %d", host, port,
123 	    (int)geteuid());
124 }
125 
126 /*
127  * Called when various events occur (see audit.h for a list of possible
128  * events and what they mean).
129  */
130 void
131 audit_event(ssh_audit_event_t event)
132 {
133 	debug("audit event euid %d user %s event %d (%s)", geteuid(),
134 	    audit_username(), event, audit_event_lookup(event));
135 }
136 
137 /*
138  * Called when a user session is started.  Argument is the tty allocated to
139  * the session, or NULL if no tty was allocated.
140  *
141  * Note that this may be called multiple times if multiple sessions are used
142  * within a single connection.
143  */
144 void
145 audit_session_open(const char *ttyn)
146 {
147 	const char *t = ttyn ? ttyn : "(no tty)";
148 
149 	debug("audit session open euid %d user %s tty name %s", geteuid(),
150 	    audit_username(), t);
151 }
152 
153 /*
154  * Called when a user session is closed.  Argument is the tty allocated to
155  * the session, or NULL if no tty was allocated.
156  *
157  * Note that this may be called multiple times if multiple sessions are used
158  * within a single connection.
159  */
160 void
161 audit_session_close(const char *ttyn)
162 {
163 	const char *t = ttyn ? ttyn : "(no tty)";
164 
165 	debug("audit session close euid %d user %s tty name %s", geteuid(),
166 	    audit_username(), t);
167 }
168 
169 /*
170  * This will be called when a user runs a non-interactive command.  Note that
171  * it may be called multiple times for a single connection since SSH2 allows
172  * multiple sessions within a single connection.
173  */
174 void
175 audit_run_command(const char *command)
176 {
177 	debug("audit run command euid %d user %s command '%.200s'", geteuid(),
178 	    audit_username(), command);
179 }
180 # endif  /* !defined CUSTOM_SSH_AUDIT_EVENTS */
181 #endif /* SSH_AUDIT_EVENTS */
182