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 */
43 extern Authctxt *the_authctxt;
44
45 /* Maybe add the audit class to struct Authmethod? */
46 ssh_audit_event_t
audit_classify_auth(const char * method)47 audit_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 */
69 const char *
audit_username(void)70 audit_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
82 const char *
audit_event_lookup(ssh_audit_event_t ev)83 audit_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 */
122 void
audit_connection_from(const char * host,int port)123 audit_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 */
133 void
audit_event(ssh_audit_event_t event)134 audit_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 */
147 void
audit_session_open(struct logininfo * li)148 audit_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 */
163 void
audit_session_close(struct logininfo * li)164 audit_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 */
177 void
audit_run_command(const char * command)178 audit_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