xref: /illumos-gate/usr/src/cmd/audit/audit.c (revision 141040e8a310da49386b596573e5dde5580572ec)
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, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 #pragma ident	"%Z%%M%	%I%	%E% SMI"
27 
28 #include <fcntl.h>
29 #include <libscf.h>
30 #include <secdb.h>
31 #include <stdlib.h>
32 #include <stdio.h>
33 #include <string.h>
34 #include <sys/file.h>
35 #include <sys/types.h>
36 #include <sys/wait.h>
37 #include <signal.h>
38 #include <sys/param.h>
39 #include <unistd.h>
40 #include <bsm/audit.h>
41 #include <bsm/libbsm.h>
42 #include <locale.h>
43 #include <audit_sig_infc.h>
44 #include <zone.h>
45 
46 #if !defined(TEXT_DOMAIN)
47 #define	TEXT_DOMAIN "SUNW_OST_OSCMD"
48 #endif
49 
50 #define	VERIFY -1
51 
52 /* GLOBALS */
53 static char	*auditdatafile = AUDITDATAFILE;
54 static char	*progname = "audit";
55 static char	*usage = "audit [-n] | [-s] | [-t] | [-v filepath]";
56 static int	silent = 0;
57 static char	*instance_name = "svc:/system/auditd:default";
58 
59 static int	get_auditd_pid();
60 static void	display_smf_error();
61 
62 static boolean_t is_audit_control_ok(char *);	/* file validation  */
63 static boolean_t is_valid_zone(boolean_t);	/* operation ok in this zone? */
64 static void	start_auditd();			/* start audit daemon */
65 
66 /*
67  * audit() - This program serves as a general administrator's interface to
68  *	the audit trail.  Only one option is valid at a time.
69  *
70  * input:
71  *	audit -s
72  *		- signal audit daemon to read audit_control file and
73  *		  start auditd if needed.
74  *	audit -n
75  *		- signal audit daemon to use next audit_control audit directory.
76  *	audit -t
77  *		- signal audit daemon to disable auditing.
78  *	audit -T
79  *		- signal audit daemon to disable auditing report no errors.
80  *	audit -v filepath
81  *		- validate audit_control parameters but use filepath for
82  *		  the name.  Emit errors or "syntax ok"
83  *
84  *
85  * output:
86  *
87  * returns:	0 - command successful
88  *		>0 - command failed
89  */
90 
91 int
92 main(int argc, char *argv[])
93 {
94 	pid_t pid; /* process id of auditd read from auditdatafile */
95 	int	sig = 0; /* signal to send auditd */
96 	char	c;
97 	char	*first_option;
98 
99 	/* Internationalization */
100 	(void) setlocale(LC_ALL, "");
101 	(void) textdomain(TEXT_DOMAIN);
102 
103 	if (getuid() != 0) {
104 		(void) fprintf(stderr, gettext("%s: not super-user\n"),
105 			progname);
106 		exit(2);
107 	}
108 	/* first option required */
109 	if ((c = getopt(argc, argv, "nstTv:")) == -1) {
110 		(void) fprintf(stderr, gettext("usage: %s\n"), usage);
111 		exit(3);
112 	}
113 	first_option = optarg;
114 	/* second or more options not allowed; please pick one */
115 	if (getopt(argc, argv, "nstTv:") != -1) {
116 		(void) fprintf(stderr, gettext("usage: %s\n"), usage);
117 		exit(5);
118 	}
119 	switch (c) {
120 	case 'n':
121 		if (!is_valid_zone(1))	/* 1 == display error if any */
122 			exit(10);
123 
124 		sig = AU_SIG_NEXT_DIR;
125 		break;
126 	case 's':
127 		if (!is_valid_zone(1))	/* 1 == display error if any */
128 			exit(10);
129 		else if (!is_audit_control_ok(NULL))
130 			exit(7);
131 
132 		start_auditd();
133 		break;
134 	case 't':
135 		if (!is_valid_zone(0))	/* 0 == no error message display */
136 			exit(0);
137 		/* use  bmsunconv to permanently disable, -t for temporary */
138 		if (smf_disable_instance(instance_name, SMF_TEMPORARY) != 0)
139 			display_smf_error();
140 		break;
141 	case 'T':
142 		if (!is_valid_zone(0))	/* 0 == no error message display */
143 			exit(0);
144 
145 		(void) smf_disable_instance(instance_name, SMF_TEMPORARY);
146 		silent = 1;
147 		break;
148 	case 'v':
149 		if (is_audit_control_ok(first_option)) {
150 			(void) fprintf(stderr, gettext("syntax ok\n"));
151 			exit(0);
152 		} else {
153 			exit(8);
154 		}
155 		break;
156 	default:
157 		(void) fprintf(stderr, gettext("usage: %s\n"), usage);
158 		exit(6);
159 	}
160 
161 	if (get_auditd_pid(&pid) != 0) {
162 		if (silent) {
163 			exit(0);
164 		} else {
165 			(void) fprintf(stderr, "%s: %s\n", progname, gettext(
166 			"can't get process id of auditd from audit_data(4)"));
167 			exit(4);
168 		}
169 	}
170 
171 	if ((sig != 0) && (kill(pid, sig) != 0)) {
172 		if (silent) {
173 			exit(0);
174 		} else {
175 			perror(progname);
176 			(void) fprintf(stderr,
177 			    gettext("%s: cannot signal auditd\n"), progname);
178 			exit(1);
179 		}
180 	}
181 	return (0);
182 }
183 
184 
185 /*
186  * get_auditd_pid(&pid):
187  *
188  * reads PID from audit_data
189  *
190  * returns:	0 - successful
191  *		1 - error
192  */
193 
194 static int
195 get_auditd_pid(pid_t *p_pid)
196 {
197 	FILE	*adp;		/* audit_data file pointer */
198 	int	retstat;
199 
200 	if ((adp = fopen(auditdatafile, "r")) == NULL) {
201 		if (!silent)
202 			perror(progname);
203 		return (1);
204 	}
205 	retstat = (fscanf(adp, "%ld", p_pid) != 1);
206 	(void) fclose(adp);
207 	return (retstat);
208 }
209 
210 /*
211  * perform reasonableness check on audit_control or its standin; goal
212  * is that "audit -s" (1) not crash the system and (2) c2audit/auditd
213  * actually generates data.
214  *
215  * A NULL input is ok -- it is used to tell _openac() to use the
216  * real audit_control file, not a substitute.
217  */
218 #define	TRADITIONAL_MAX	1024
219 
220 static boolean_t
221 is_audit_control_ok(char *filename) {
222 	char		buf[TRADITIONAL_MAX];
223 	int		outputs = 0;
224 	int		state = 1;	/* 1 is ok, 0 is not */
225 	int		rc;
226 	int		min;
227 	kva_t		*kvlist;
228 	char		*value;
229 	au_acinfo_t	*ach;
230 
231 	ach = _openac(filename);	/* open audit_control */
232 	if (ach == NULL) {
233 		perror(progname);
234 		exit(9);
235 	}
236 	/*
237 	 * There must be at least one directory or one plugin
238 	 * defined.
239 	 */
240 	if ((rc = _getacdir(ach, buf, TRADITIONAL_MAX)) == 0) {
241 		outputs++;
242 	} else if (rc < -1) {	/* -1 is not found, others are errors */
243 		(void) fprintf(stderr,
244 			gettext("%s: audit_control \"dir:\" spec invalid\n"),
245 				progname);
246 		state = 0;	/* is_not_ok */
247 	}
248 
249 	/*
250 	 * _getacplug -- all that is of interest is the return code.
251 	 */
252 	_rewindac(ach);	/* rewind audit_control */
253 	if ((rc = _getacplug(ach, &kvlist)) == 0) {
254 		value = kva_match(kvlist, "name");
255 		if (value == NULL) {
256 			(void) fprintf(stderr, gettext("%s: audit_control "
257 			    "\"plugin:\" missing name\n"), progname);
258 			state = 0;	/* is_not_ok */
259 		}
260 		else
261 			outputs++;
262 
263 		_kva_free(kvlist);
264 	} else if (rc < -1) {
265 		(void) fprintf(stderr,
266 			gettext("%s: audit_control \"plugin:\" spec invalid\n"),
267 				progname);
268 		state = 0;	/* is_not_ok */
269 	}
270 	if (outputs == 0) {
271 		(void) fprintf(stderr,
272 			gettext("%s: audit_control must have either a "
273 				"\"dir:\" or a \"plugin:\" specified.\n"),
274 				progname);
275 		state = 0;	/* is_not_ok */
276 	}
277 	/* minfree is not required */
278 	_rewindac(ach);
279 	if ((rc = _getacmin(ach, &min)) < -1) {
280 		(void) fprintf(stderr,
281 			gettext(
282 			    "%s: audit_control \"minfree:\" spec invalid\n"),
283 			    progname);
284 		state = 0;	/* is_not_ok */
285 	}
286 	/* flags is not required */
287 	_rewindac(ach);
288 	if ((rc = _getacflg(ach, buf, TRADITIONAL_MAX)) < -1) {
289 		(void) fprintf(stderr,
290 			gettext("%s: audit_control \"flags:\" spec invalid\n"),
291 				progname);
292 		state = 0;	/* is_not_ok */
293 	}
294 	/* naflags is not required */
295 	_rewindac(ach);
296 	if ((rc = _getacna(ach, buf, TRADITIONAL_MAX)) < -1) {
297 		(void) fprintf(stderr,
298 			gettext(
299 			    "%s: audit_control \"naflags:\" spec invalid\n"),
300 			    progname);
301 		state = 0;	/* is_not_ok */
302 	}
303 	_endac(ach);
304 	return (state);
305 }
306 
307 /*
308  * The operations that call this function are only valid in the global
309  * zone unless the perzone audit policy is set.
310  *
311  * "!silent" and "show_err" are slightly different; silent is from
312  * -T for which no error messages should be displayed and show_err
313  * applies to more options (including -T)
314  *
315  */
316 
317 static boolean_t
318 is_valid_zone(boolean_t show_err)
319 {
320 	long	policy;
321 
322 	if (auditon(A_GETPOLICY, (char *)&policy, 0) == -1) {
323 		if (!silent)
324 			(void) fprintf(stderr, gettext(
325 			    "%s: Cannot read audit policy:  %s\n"),
326 			    progname, strerror(errno));
327 		return (0);
328 	}
329 	if (policy & AUDIT_PERZONE)
330 		return (1);
331 
332 	if (getzoneid() != GLOBAL_ZONEID) {
333 		if (show_err)
334 			(void) fprintf(stderr,
335 			    gettext("%s: Not valid in a local zone.\n"),
336 			    progname);
337 		return (0);
338 	} else {
339 		return (1);
340 	}
341 }
342 
343 /*
344  * if auditd isn't running, start it.  Otherwise refresh.
345  * First check to see if c2audit is loaded via the auditon()
346  * system call, then check SMF state.
347  */
348 static void
349 start_auditd()
350 {
351 	int	audit_state;
352 	char	*state;
353 
354 	if (auditon(A_GETCOND, (caddr_t)&audit_state,
355 	    sizeof (audit_state)) != 0)
356 		return;
357 
358 	if ((state = smf_get_state(instance_name)) == NULL) {
359 		display_smf_error();
360 		return;
361 	}
362 	if (strcmp(SCF_STATE_STRING_ONLINE, state) != 0) {
363 		if (smf_enable_instance(instance_name, 0) != 0)
364 			display_smf_error();
365 	} else {
366 		if (smf_refresh_instance(instance_name) != 0)
367 			display_smf_error();
368 	}
369 	free(state);
370 }
371 
372 static void
373 display_smf_error()
374 {
375 	int	rc = scf_error();
376 
377 	switch (rc) {
378 	case SCF_ERROR_NOT_FOUND:
379 		(void) fprintf(stderr,
380 		    "SMF error: \"%s\" not found.\n",
381 		    instance_name);
382 		break;
383 	default:
384 		(void) fprintf(stderr, "SMF error %d\n", rc);
385 		break;
386 	}
387 }
388