xref: /illumos-gate/usr/src/cmd/audit/audit.c (revision 57c40785)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 #pragma ident	"%Z%%M%	%I%	%E% SMI"
26 
27 #include <fcntl.h>
28 #include <libscf.h>
29 #include <secdb.h>
30 #include <stdlib.h>
31 #include <stdio.h>
32 #include <string.h>
33 #include <sys/file.h>
34 #include <sys/types.h>
35 #include <sys/wait.h>
36 #include <signal.h>
37 #include <sys/param.h>
38 #include <unistd.h>
39 #include <bsm/audit.h>
40 #include <bsm/libbsm.h>
41 #include <locale.h>
42 #include <audit_sig_infc.h>
43 #include <zone.h>
44 
45 #if !defined(TEXT_DOMAIN)
46 #define	TEXT_DOMAIN "SUNW_OST_OSCMD"
47 #endif
48 
49 #define	VERIFY -1
50 
51 /* GLOBALS */
52 static char	*auditdatafile = AUDITDATAFILE;
53 static char	*progname = "audit";
54 static char	*usage = "audit [-n] | [-s] | [-t] | [-v filepath]";
55 static int	silent = 0;
56 static char	*instance_name = "svc:/system/auditd:default";
57 
58 static int	get_auditd_pid();
59 static void	display_smf_error();
60 
61 static boolean_t is_audit_control_ok(char *);	/* file validation  */
62 static boolean_t is_valid_zone(boolean_t);	/* operation ok in this zone? */
63 static int	start_auditd();			/* start audit daemon */
64 
65 /*
66  * audit() - This program serves as a general administrator's interface to
67  *	the audit trail.  Only one option is valid at a time.
68  *
69  * input:
70  *	audit -s
71  *		- signal audit daemon to read audit_control file and
72  *		  start auditd if needed.
73  *	audit -n
74  *		- signal audit daemon to use next audit_control audit directory.
75  *	audit -t
76  *		- signal audit daemon to disable auditing.
77  *	audit -T
78  *		- signal audit daemon to disable auditing report no errors.
79  *	audit -v filepath
80  *		- validate audit_control parameters but use filepath for
81  *		  the name.  Emit errors or "syntax ok"
82  *
83  *
84  * output:
85  *
86  * returns:	0 - command successful
87  *		>0 - command failed
88  */
89 
90 int
91 main(int argc, char *argv[])
92 {
93 	pid_t pid; /* process id of auditd read from auditdatafile */
94 	int	sig = 0; /* signal to send auditd */
95 	char	c;
96 	char	*first_option;
97 
98 	/* Internationalization */
99 	(void) setlocale(LC_ALL, "");
100 	(void) textdomain(TEXT_DOMAIN);
101 
102 	/* first option required */
103 	if ((c = getopt(argc, argv, "nstTv:")) == -1) {
104 		(void) fprintf(stderr, gettext("usage: %s\n"), usage);
105 		exit(3);
106 	}
107 	first_option = optarg;
108 	/* second or more options not allowed; please pick one */
109 	if (getopt(argc, argv, "nstTv:") != -1) {
110 		(void) fprintf(stderr, gettext("usage: %s\n"), usage);
111 		exit(5);
112 	}
113 	switch (c) {
114 	case 'n':
115 		if (!is_valid_zone(1))	/* 1 == display error if any */
116 			exit(10);
117 
118 		sig = AU_SIG_NEXT_DIR;
119 		break;
120 	case 's':
121 		if (!is_valid_zone(1))	/* 1 == display error if any */
122 			exit(10);
123 		else if (!is_audit_control_ok(NULL))
124 			exit(7);
125 
126 		return (start_auditd());
127 	case 't':
128 		if (!is_valid_zone(0))	/* 0 == no error message display */
129 			exit(10);
130 		/* use bmsunconv to permanently disable, -t for temporary */
131 		if (smf_disable_instance(instance_name, SMF_TEMPORARY) != 0) {
132 			display_smf_error();
133 			exit(11);
134 		}
135 		break;
136 	case 'T':
137 		silent = 1;
138 		if (!is_valid_zone(0))	/* 0 == no error message display */
139 			exit(10);
140 
141 		if (smf_disable_instance(instance_name, SMF_TEMPORARY) != 0) {
142 			exit(11);
143 		}
144 		break;
145 	case 'v':
146 		if (is_audit_control_ok(first_option)) {
147 			(void) fprintf(stderr, gettext("syntax ok\n"));
148 			exit(0);
149 		} else {
150 			exit(8);
151 		}
152 		break;
153 	default:
154 		(void) fprintf(stderr, gettext("usage: %s\n"), usage);
155 		exit(6);
156 	}
157 
158 	if (sig != 0) {
159 		if (get_auditd_pid(&pid) != 0) {
160 			(void) fprintf(stderr, "%s: %s\n", progname,
161 			    gettext("can't get process id of auditd from "
162 			    "audit_data(4)"));
163 			exit(4);
164 		}
165 
166 		if (kill(pid, sig) != 0) {
167 			perror(progname);
168 			(void) fprintf(stderr,
169 			    gettext("%s: cannot signal auditd\n"), progname);
170 			exit(1);
171 		}
172 	}
173 	return (0);
174 }
175 
176 
177 /*
178  * get_auditd_pid(&pid):
179  *
180  * reads PID from audit_data
181  *
182  * returns:	0 - successful
183  *		1 - error
184  */
185 
186 static int
187 get_auditd_pid(pid_t *p_pid)
188 {
189 	FILE	*adp;		/* audit_data file pointer */
190 	int	retstat;
191 
192 	if ((adp = fopen(auditdatafile, "r")) == NULL) {
193 		if (!silent)
194 			perror(progname);
195 		return (1);
196 	}
197 	retstat = (fscanf(adp, "%ld", p_pid) != 1);
198 	(void) fclose(adp);
199 	return (retstat);
200 }
201 
202 /*
203  * perform reasonableness check on audit_control or its standin; goal
204  * is that "audit -s" (1) not crash the system and (2) c2audit/auditd
205  * actually generates data.
206  *
207  * A NULL input is ok -- it is used to tell _openac() to use the
208  * real audit_control file, not a substitute.
209  */
210 #define	TRADITIONAL_MAX	1024
211 
212 static boolean_t
213 is_audit_control_ok(char *filename) {
214 	char		buf[TRADITIONAL_MAX];
215 	int		outputs = 0;
216 	int		state = 1;	/* 1 is ok, 0 is not */
217 	int		rc;
218 	int		min;
219 	kva_t		*kvlist;
220 	char		*plugin_name;
221 	char		*plugin_dir;
222 	au_acinfo_t	*ach;
223 
224 	ach = _openac(filename);	/* open audit_control */
225 	if (ach == NULL) {
226 		perror(progname);
227 		exit(9);
228 	}
229 	/*
230 	 * There must be at least one directory or one plugin
231 	 * defined.
232 	 */
233 	if ((rc = _getacdir(ach, buf, TRADITIONAL_MAX)) == 0) {
234 		outputs++;
235 	} else if (rc < -1) {	/* -1 is not found, others are errors */
236 		(void) fprintf(stderr,
237 			gettext("%s: audit_control \"dir:\" spec invalid\n"),
238 				progname);
239 		state = 0;	/* is_not_ok */
240 	}
241 
242 	/*
243 	 * _getacplug -- all that is of interest is the return code.
244 	 */
245 	_rewindac(ach);	/* rewind audit_control */
246 	while ((rc = _getacplug(ach, &kvlist)) == 0) {
247 		plugin_name = kva_match(kvlist, "name");
248 		if (plugin_name == NULL) {
249 			(void) fprintf(stderr, gettext("%s: audit_control "
250 			    "\"plugin:\" missing name\n"), progname);
251 			state = 0;	/* is_not_ok */
252 		} else {
253 			if (strcmp(plugin_name, "audit_binfile.so") == 0) {
254 				plugin_dir = kva_match(kvlist, "p_dir");
255 				if ((plugin_dir == NULL) && (outputs == 0)) {
256 					(void) fprintf(stderr,
257 					    gettext("%s: audit_control "
258 					    "\"plugin:\" missing p_dir\n"),
259 					    progname);
260 					state = 0;	/* is_not_ok */
261 				} else {
262 					outputs++;
263 				}
264 			}
265 		}
266 		_kva_free(kvlist);
267 	}
268 	if (rc < -1) {
269 		(void) fprintf(stderr,
270 			gettext("%s: audit_control \"plugin:\" spec invalid\n"),
271 				progname);
272 		state = 0;	/* is_not_ok */
273 	}
274 	if (outputs == 0) {
275 		(void) fprintf(stderr,
276 			gettext("%s: audit_control must have either a "
277 				"valid \"dir:\" entry or a valid \"plugin:\" "
278 				"entry with \"p_dir:\" specified.\n"),
279 				progname);
280 		state = 0;	/* is_not_ok */
281 	}
282 	/* minfree is not required */
283 	_rewindac(ach);
284 	if ((rc = _getacmin(ach, &min)) < -1) {
285 		(void) fprintf(stderr,
286 			gettext(
287 			    "%s: audit_control \"minfree:\" spec invalid\n"),
288 			    progname);
289 		state = 0;	/* is_not_ok */
290 	}
291 	/* flags is not required */
292 	_rewindac(ach);
293 	if ((rc = _getacflg(ach, buf, TRADITIONAL_MAX)) < -1) {
294 		(void) fprintf(stderr,
295 			gettext("%s: audit_control \"flags:\" spec invalid\n"),
296 				progname);
297 		state = 0;	/* is_not_ok */
298 	}
299 	/* naflags is not required */
300 	_rewindac(ach);
301 	if ((rc = _getacna(ach, buf, TRADITIONAL_MAX)) < -1) {
302 		(void) fprintf(stderr,
303 			gettext(
304 			    "%s: audit_control \"naflags:\" spec invalid\n"),
305 			    progname);
306 		state = 0;	/* is_not_ok */
307 	}
308 	_endac(ach);
309 	return (state);
310 }
311 
312 /*
313  * The operations that call this function are only valid in the global
314  * zone unless the perzone audit policy is set.
315  *
316  * "!silent" and "show_err" are slightly different; silent is from
317  * -T for which no error messages should be displayed and show_err
318  * applies to more options (including -T)
319  *
320  */
321 
322 static boolean_t
323 is_valid_zone(boolean_t show_err)
324 {
325 	long	policy;
326 
327 	if (auditon(A_GETPOLICY, (char *)&policy, 0) == -1) {
328 		if (!silent)
329 			(void) fprintf(stderr, gettext(
330 			    "%s: Cannot read audit policy:  %s\n"),
331 			    progname, strerror(errno));
332 		return (0);
333 	}
334 	if (policy & AUDIT_PERZONE)
335 		return (1);
336 
337 	if (getzoneid() != GLOBAL_ZONEID) {
338 		if (show_err)
339 			(void) fprintf(stderr,
340 			    gettext("%s: Not valid in a local zone.\n"),
341 			    progname);
342 		return (0);
343 	} else {
344 		return (1);
345 	}
346 }
347 
348 /*
349  * if auditd isn't running, start it.  Otherwise refresh.
350  * First check to see if c2audit is loaded via the auditon()
351  * system call, then check SMF state.
352  */
353 static int
354 start_auditd()
355 {
356 	int	audit_state;
357 	char	*state;
358 
359 	if (auditon(A_GETCOND, (caddr_t)&audit_state,
360 	    sizeof (audit_state)) != 0)
361 		return (12);
362 
363 	if ((state = smf_get_state(instance_name)) == NULL) {
364 		display_smf_error();
365 		return (13);
366 	}
367 	if (strcmp(SCF_STATE_STRING_ONLINE, state) != 0) {
368 		if (smf_enable_instance(instance_name, 0) != 0) {
369 			display_smf_error();
370 			free(state);
371 			return (14);
372 		}
373 	} else {
374 		if (smf_refresh_instance(instance_name) != 0) {
375 			display_smf_error();
376 			free(state);
377 			return (15);
378 		}
379 	}
380 	free(state);
381 	return (0);
382 }
383 
384 static void
385 display_smf_error()
386 {
387 	int	rc = scf_error();
388 
389 	switch (rc) {
390 	case SCF_ERROR_NOT_FOUND:
391 		(void) fprintf(stderr,
392 		    "SMF error: \"%s\" not found.\n",
393 		    instance_name);
394 		break;
395 	default:
396 		(void) fprintf(stderr, "SMF error: %s\n", scf_strerror(rc));
397 		break;
398 	}
399 }
400