xref: /illumos-gate/usr/src/cmd/audit/audit.c (revision 9a016c63ca347047a236dff12f0da83aac8981d1)
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 	if (getuid() != 0) {
103 		(void) fprintf(stderr, gettext("%s: not super-user\n"),
104 			progname);
105 		exit(2);
106 	}
107 	/* first option required */
108 	if ((c = getopt(argc, argv, "nstTv:")) == -1) {
109 		(void) fprintf(stderr, gettext("usage: %s\n"), usage);
110 		exit(3);
111 	}
112 	first_option = optarg;
113 	/* second or more options not allowed; please pick one */
114 	if (getopt(argc, argv, "nstTv:") != -1) {
115 		(void) fprintf(stderr, gettext("usage: %s\n"), usage);
116 		exit(5);
117 	}
118 	switch (c) {
119 	case 'n':
120 		if (!is_valid_zone(1))	/* 1 == display error if any */
121 			exit(10);
122 
123 		sig = AU_SIG_NEXT_DIR;
124 		break;
125 	case 's':
126 		if (!is_valid_zone(1))	/* 1 == display error if any */
127 			exit(10);
128 		else if (!is_audit_control_ok(NULL))
129 			exit(7);
130 
131 		return (start_auditd());
132 	case 't':
133 		if (!is_valid_zone(0))	/* 0 == no error message display */
134 			exit(10);
135 		/* use bmsunconv to permanently disable, -t for temporary */
136 		if (smf_disable_instance(instance_name, SMF_TEMPORARY) != 0) {
137 			display_smf_error();
138 			exit(11);
139 		}
140 		break;
141 	case 'T':
142 		silent = 1;
143 		if (!is_valid_zone(0))	/* 0 == no error message display */
144 			exit(10);
145 
146 		if (smf_disable_instance(instance_name, SMF_TEMPORARY) != 0) {
147 			exit(11);
148 		}
149 		break;
150 	case 'v':
151 		if (is_audit_control_ok(first_option)) {
152 			(void) fprintf(stderr, gettext("syntax ok\n"));
153 			exit(0);
154 		} else {
155 			exit(8);
156 		}
157 		break;
158 	default:
159 		(void) fprintf(stderr, gettext("usage: %s\n"), usage);
160 		exit(6);
161 	}
162 
163 	if (sig != 0) {
164 		if (get_auditd_pid(&pid) != 0) {
165 			(void) fprintf(stderr, "%s: %s\n", progname,
166 			    gettext("can't get process id of auditd from "
167 			    "audit_data(4)"));
168 			exit(4);
169 		}
170 
171 		if (kill(pid, sig) != 0) {
172 			perror(progname);
173 			(void) fprintf(stderr,
174 			    gettext("%s: cannot signal auditd\n"), progname);
175 			exit(1);
176 		}
177 	}
178 	return (0);
179 }
180 
181 
182 /*
183  * get_auditd_pid(&pid):
184  *
185  * reads PID from audit_data
186  *
187  * returns:	0 - successful
188  *		1 - error
189  */
190 
191 static int
192 get_auditd_pid(pid_t *p_pid)
193 {
194 	FILE	*adp;		/* audit_data file pointer */
195 	int	retstat;
196 
197 	if ((adp = fopen(auditdatafile, "r")) == NULL) {
198 		if (!silent)
199 			perror(progname);
200 		return (1);
201 	}
202 	retstat = (fscanf(adp, "%ld", p_pid) != 1);
203 	(void) fclose(adp);
204 	return (retstat);
205 }
206 
207 /*
208  * perform reasonableness check on audit_control or its standin; goal
209  * is that "audit -s" (1) not crash the system and (2) c2audit/auditd
210  * actually generates data.
211  *
212  * A NULL input is ok -- it is used to tell _openac() to use the
213  * real audit_control file, not a substitute.
214  */
215 #define	TRADITIONAL_MAX	1024
216 
217 static boolean_t
218 is_audit_control_ok(char *filename) {
219 	char		buf[TRADITIONAL_MAX];
220 	int		outputs = 0;
221 	int		state = 1;	/* 1 is ok, 0 is not */
222 	int		rc;
223 	int		min;
224 	kva_t		*kvlist;
225 	char		*value;
226 	au_acinfo_t	*ach;
227 
228 	ach = _openac(filename);	/* open audit_control */
229 	if (ach == NULL) {
230 		perror(progname);
231 		exit(9);
232 	}
233 	/*
234 	 * There must be at least one directory or one plugin
235 	 * defined.
236 	 */
237 	if ((rc = _getacdir(ach, buf, TRADITIONAL_MAX)) == 0) {
238 		outputs++;
239 	} else if (rc < -1) {	/* -1 is not found, others are errors */
240 		(void) fprintf(stderr,
241 			gettext("%s: audit_control \"dir:\" spec invalid\n"),
242 				progname);
243 		state = 0;	/* is_not_ok */
244 	}
245 
246 	/*
247 	 * _getacplug -- all that is of interest is the return code.
248 	 */
249 	_rewindac(ach);	/* rewind audit_control */
250 	if ((rc = _getacplug(ach, &kvlist)) == 0) {
251 		value = kva_match(kvlist, "name");
252 		if (value == NULL) {
253 			(void) fprintf(stderr, gettext("%s: audit_control "
254 			    "\"plugin:\" missing name\n"), progname);
255 			state = 0;	/* is_not_ok */
256 		}
257 		else
258 			outputs++;
259 
260 		_kva_free(kvlist);
261 	} else if (rc < -1) {
262 		(void) fprintf(stderr,
263 			gettext("%s: audit_control \"plugin:\" spec invalid\n"),
264 				progname);
265 		state = 0;	/* is_not_ok */
266 	}
267 	if (outputs == 0) {
268 		(void) fprintf(stderr,
269 			gettext("%s: audit_control must have either a "
270 				"\"dir:\" or a \"plugin:\" specified.\n"),
271 				progname);
272 		state = 0;	/* is_not_ok */
273 	}
274 	/* minfree is not required */
275 	_rewindac(ach);
276 	if ((rc = _getacmin(ach, &min)) < -1) {
277 		(void) fprintf(stderr,
278 			gettext(
279 			    "%s: audit_control \"minfree:\" spec invalid\n"),
280 			    progname);
281 		state = 0;	/* is_not_ok */
282 	}
283 	/* flags is not required */
284 	_rewindac(ach);
285 	if ((rc = _getacflg(ach, buf, TRADITIONAL_MAX)) < -1) {
286 		(void) fprintf(stderr,
287 			gettext("%s: audit_control \"flags:\" spec invalid\n"),
288 				progname);
289 		state = 0;	/* is_not_ok */
290 	}
291 	/* naflags is not required */
292 	_rewindac(ach);
293 	if ((rc = _getacna(ach, buf, TRADITIONAL_MAX)) < -1) {
294 		(void) fprintf(stderr,
295 			gettext(
296 			    "%s: audit_control \"naflags:\" spec invalid\n"),
297 			    progname);
298 		state = 0;	/* is_not_ok */
299 	}
300 	_endac(ach);
301 	return (state);
302 }
303 
304 /*
305  * The operations that call this function are only valid in the global
306  * zone unless the perzone audit policy is set.
307  *
308  * "!silent" and "show_err" are slightly different; silent is from
309  * -T for which no error messages should be displayed and show_err
310  * applies to more options (including -T)
311  *
312  */
313 
314 static boolean_t
315 is_valid_zone(boolean_t show_err)
316 {
317 	long	policy;
318 
319 	if (auditon(A_GETPOLICY, (char *)&policy, 0) == -1) {
320 		if (!silent)
321 			(void) fprintf(stderr, gettext(
322 			    "%s: Cannot read audit policy:  %s\n"),
323 			    progname, strerror(errno));
324 		return (0);
325 	}
326 	if (policy & AUDIT_PERZONE)
327 		return (1);
328 
329 	if (getzoneid() != GLOBAL_ZONEID) {
330 		if (show_err)
331 			(void) fprintf(stderr,
332 			    gettext("%s: Not valid in a local zone.\n"),
333 			    progname);
334 		return (0);
335 	} else {
336 		return (1);
337 	}
338 }
339 
340 /*
341  * if auditd isn't running, start it.  Otherwise refresh.
342  * First check to see if c2audit is loaded via the auditon()
343  * system call, then check SMF state.
344  */
345 static int
346 start_auditd()
347 {
348 	int	audit_state;
349 	char	*state;
350 
351 	if (auditon(A_GETCOND, (caddr_t)&audit_state,
352 	    sizeof (audit_state)) != 0)
353 		return (12);
354 
355 	if ((state = smf_get_state(instance_name)) == NULL) {
356 		display_smf_error();
357 		return (13);
358 	}
359 	if (strcmp(SCF_STATE_STRING_ONLINE, state) != 0) {
360 		if (smf_enable_instance(instance_name, 0) != 0) {
361 			display_smf_error();
362 			free(state);
363 			return (14);
364 		}
365 	} else {
366 		if (smf_refresh_instance(instance_name) != 0) {
367 			display_smf_error();
368 			free(state);
369 			return (15);
370 		}
371 	}
372 	free(state);
373 	return (0);
374 }
375 
376 static void
377 display_smf_error()
378 {
379 	int	rc = scf_error();
380 
381 	switch (rc) {
382 	case SCF_ERROR_NOT_FOUND:
383 		(void) fprintf(stderr,
384 		    "SMF error: \"%s\" not found.\n",
385 		    instance_name);
386 		break;
387 	default:
388 		(void) fprintf(stderr, "SMF error: %s\n", scf_strerror(rc));
389 		break;
390 	}
391 }
392