xref: /illumos-gate/usr/src/cmd/audit/audit.c (revision f4b3ec61df05330d25f55a36b975b4d7519fdeb1)
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 2006 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		*value;
221 	au_acinfo_t	*ach;
222 
223 	ach = _openac(filename);	/* open audit_control */
224 	if (ach == NULL) {
225 		perror(progname);
226 		exit(9);
227 	}
228 	/*
229 	 * There must be at least one directory or one plugin
230 	 * defined.
231 	 */
232 	if ((rc = _getacdir(ach, buf, TRADITIONAL_MAX)) == 0) {
233 		outputs++;
234 	} else if (rc < -1) {	/* -1 is not found, others are errors */
235 		(void) fprintf(stderr,
236 			gettext("%s: audit_control \"dir:\" spec invalid\n"),
237 				progname);
238 		state = 0;	/* is_not_ok */
239 	}
240 
241 	/*
242 	 * _getacplug -- all that is of interest is the return code.
243 	 */
244 	_rewindac(ach);	/* rewind audit_control */
245 	if ((rc = _getacplug(ach, &kvlist)) == 0) {
246 		value = kva_match(kvlist, "name");
247 		if (value == NULL) {
248 			(void) fprintf(stderr, gettext("%s: audit_control "
249 			    "\"plugin:\" missing name\n"), progname);
250 			state = 0;	/* is_not_ok */
251 		}
252 		else
253 			outputs++;
254 
255 		_kva_free(kvlist);
256 	} else if (rc < -1) {
257 		(void) fprintf(stderr,
258 			gettext("%s: audit_control \"plugin:\" spec invalid\n"),
259 				progname);
260 		state = 0;	/* is_not_ok */
261 	}
262 	if (outputs == 0) {
263 		(void) fprintf(stderr,
264 			gettext("%s: audit_control must have either a "
265 				"\"dir:\" or a \"plugin:\" specified.\n"),
266 				progname);
267 		state = 0;	/* is_not_ok */
268 	}
269 	/* minfree is not required */
270 	_rewindac(ach);
271 	if ((rc = _getacmin(ach, &min)) < -1) {
272 		(void) fprintf(stderr,
273 			gettext(
274 			    "%s: audit_control \"minfree:\" spec invalid\n"),
275 			    progname);
276 		state = 0;	/* is_not_ok */
277 	}
278 	/* flags is not required */
279 	_rewindac(ach);
280 	if ((rc = _getacflg(ach, buf, TRADITIONAL_MAX)) < -1) {
281 		(void) fprintf(stderr,
282 			gettext("%s: audit_control \"flags:\" spec invalid\n"),
283 				progname);
284 		state = 0;	/* is_not_ok */
285 	}
286 	/* naflags is not required */
287 	_rewindac(ach);
288 	if ((rc = _getacna(ach, buf, TRADITIONAL_MAX)) < -1) {
289 		(void) fprintf(stderr,
290 			gettext(
291 			    "%s: audit_control \"naflags:\" spec invalid\n"),
292 			    progname);
293 		state = 0;	/* is_not_ok */
294 	}
295 	_endac(ach);
296 	return (state);
297 }
298 
299 /*
300  * The operations that call this function are only valid in the global
301  * zone unless the perzone audit policy is set.
302  *
303  * "!silent" and "show_err" are slightly different; silent is from
304  * -T for which no error messages should be displayed and show_err
305  * applies to more options (including -T)
306  *
307  */
308 
309 static boolean_t
310 is_valid_zone(boolean_t show_err)
311 {
312 	long	policy;
313 
314 	if (auditon(A_GETPOLICY, (char *)&policy, 0) == -1) {
315 		if (!silent)
316 			(void) fprintf(stderr, gettext(
317 			    "%s: Cannot read audit policy:  %s\n"),
318 			    progname, strerror(errno));
319 		return (0);
320 	}
321 	if (policy & AUDIT_PERZONE)
322 		return (1);
323 
324 	if (getzoneid() != GLOBAL_ZONEID) {
325 		if (show_err)
326 			(void) fprintf(stderr,
327 			    gettext("%s: Not valid in a local zone.\n"),
328 			    progname);
329 		return (0);
330 	} else {
331 		return (1);
332 	}
333 }
334 
335 /*
336  * if auditd isn't running, start it.  Otherwise refresh.
337  * First check to see if c2audit is loaded via the auditon()
338  * system call, then check SMF state.
339  */
340 static int
341 start_auditd()
342 {
343 	int	audit_state;
344 	char	*state;
345 
346 	if (auditon(A_GETCOND, (caddr_t)&audit_state,
347 	    sizeof (audit_state)) != 0)
348 		return (12);
349 
350 	if ((state = smf_get_state(instance_name)) == NULL) {
351 		display_smf_error();
352 		return (13);
353 	}
354 	if (strcmp(SCF_STATE_STRING_ONLINE, state) != 0) {
355 		if (smf_enable_instance(instance_name, 0) != 0) {
356 			display_smf_error();
357 			free(state);
358 			return (14);
359 		}
360 	} else {
361 		if (smf_refresh_instance(instance_name) != 0) {
362 			display_smf_error();
363 			free(state);
364 			return (15);
365 		}
366 	}
367 	free(state);
368 	return (0);
369 }
370 
371 static void
372 display_smf_error()
373 {
374 	int	rc = scf_error();
375 
376 	switch (rc) {
377 	case SCF_ERROR_NOT_FOUND:
378 		(void) fprintf(stderr,
379 		    "SMF error: \"%s\" not found.\n",
380 		    instance_name);
381 		break;
382 	default:
383 		(void) fprintf(stderr, "SMF error: %s\n", scf_strerror(rc));
384 		break;
385 	}
386 }
387