xref: /titanic_41/usr/src/lib/libbsm/common/audit_event.c (revision 0a44ef6d9afbfe052a7e975f55ea0d2954b62a82)
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 #pragma ident	"%Z%%M%	%I%	%E% SMI"
22 
23 #ifndef lint
24 static char	sccsid[] = "%Z%%M% %I% %E% SMI";
25 #endif
26 
27 /*
28  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
29  * Use is subject to license terms.
30  */
31 
32 /*
33  * Interfaces to audit_event(5)  (/etc/security/audit_event)
34  */
35 
36 /*
37  * This routine is obsolete.  I have removed its inclusion by removing
38  * the .o from the makefile.  Please use cacheauevent() or any of the
39  * getauev* routines.
40  */
41 
42 #include <sys/types.h>
43 #include <limits.h>
44 #include <stdio.h>
45 #include <stdlib.h>
46 #include <string.h>
47 #include <bsm/audit.h>
48 #include <bsm/libbsm.h>
49 #include <synch.h>
50 
51 /*
52  *	Macros to produce a quoted string containing the value of a
53  *	preprocessor macro. For example, if SIZE is defined to be 256,
54  *	VAL2STR(SIZE) is "256". This is used to construct format
55  *	strings for scanf-family functions below.
56  */
57 #define	QUOTE(x)	#x
58 #define	VAL2STR(x)	QUOTE(x)
59 
60 static au_class_t flagstohex(char *);
61 
62 static char	au_event_fname[PATH_MAX] = AUDITEVENTFILE;
63 static FILE *au_event_file = (FILE *)0;
64 static mutex_t mutex_eventfile = DEFAULTMUTEX;
65 static mutex_t mutex_eventcache = DEFAULTMUTEX;
66 /*
67  * If an error occurs during the call to cacheauclassnam() inside
68  * flagstohex() any return value could be seen as a valid class mask so
69  * the following global variable, cacheauclass_failure, is set to indicate
70  * that an error has occurred.
71  */
72 static int cacheauclass_failure = 0;
73 
74 extern int _mutex_lock(mutex_t *);
75 extern int _mutex_unlock(mutex_t *);
76 
77 
78 void
79 setauevent()
80 {
81 	_mutex_lock(&mutex_eventfile);
82 	if (au_event_file) {
83 		(void) fseek(au_event_file, 0L, 0);
84 	}
85 	_mutex_unlock(&mutex_eventfile);
86 }
87 
88 
89 void
90 endauevent()
91 {
92 	_mutex_lock(&mutex_eventfile);
93 	if (au_event_file) {
94 		(void) fclose(au_event_file);
95 		au_event_file = (FILE *)0;
96 	}
97 	_mutex_unlock(&mutex_eventfile);
98 }
99 
100 au_event_ent_t *
101 getauevent()
102 {
103 	static au_event_ent_t au_event_entry;
104 	static char	ename[AU_EVENT_NAME_MAX];
105 	static char	edesc[AU_EVENT_DESC_MAX];
106 
107 	/* initialize au_event_entry structure */
108 	au_event_entry.ae_name = ename;
109 	au_event_entry.ae_desc = edesc;
110 
111 	return (getauevent_r(&au_event_entry));
112 }
113 
114 au_event_ent_t *
115 getauevent_r(au_event_entry)
116 	au_event_ent_t *au_event_entry;
117 {
118 	int	i, error = 0, found = 0;
119 	char	*s, input[AU_EVENT_LINE_MAX];
120 	char	trim_buf[AU_EVENT_NAME_MAX+1];
121 
122 	/* open audit event file if it isn't already */
123 	_mutex_lock(&mutex_eventfile);
124 	if (!au_event_file)
125 		if (!(au_event_file = fopen(au_event_fname, "rF"))) {
126 			_mutex_unlock(&mutex_eventfile);
127 			return ((au_event_ent_t *)0);
128 		}
129 
130 	while (fgets(input, AU_EVENT_LINE_MAX, au_event_file)) {
131 		if (input[0] != '#') {
132 			s = input + strspn(input, " \t\r\n");
133 			if ((*s == '\0') || (*s == '#')) {
134 				continue;
135 			}
136 			found = 1;
137 			s = input;
138 
139 			/* parse number */
140 			i = strcspn(s, ":");
141 			s[i] = '\0';
142 			(void) sscanf(s, "%hd", &au_event_entry->ae_number);
143 			s = &s[i+1];
144 
145 			/* parse event name */
146 			i = strcspn(s, ":");
147 			s[i] = '\0';
148 			(void) sscanf(s, "%" VAL2STR(AU_EVENT_NAME_MAX) "s",
149 			    trim_buf);
150 			(void) strncpy(au_event_entry->ae_name, trim_buf,
151 				AU_EVENT_NAME_MAX);
152 			s = &s[i+1];
153 
154 			/* parse event description */
155 			i = strcspn(s, ":");
156 			s[i] = '\0';
157 			(void) strncpy(au_event_entry->ae_desc, s,
158 				AU_EVENT_DESC_MAX);
159 			s = &s[i+1];
160 
161 			/* parse class */
162 			i = strcspn(s, "\n\0");
163 			s[i] = '\0';
164 			(void) sscanf(s, "%" VAL2STR(AU_EVENT_NAME_MAX) "s",
165 			    trim_buf);
166 			au_event_entry->ae_class = flagstohex(trim_buf);
167 			if (cacheauclass_failure == 1) {
168 				error = 1;
169 				cacheauclass_failure = 0;
170 			}
171 
172 			break;
173 		}
174 	}
175 	_mutex_unlock(&mutex_eventfile);
176 
177 	if (!error && found) {
178 		return (au_event_entry);
179 	} else {
180 		return ((au_event_ent_t *)0);
181 	}
182 }
183 
184 
185 au_event_ent_t *
186 #ifdef __STDC__
187 getauevnam(char *name)
188 #else
189 getauevnam(name)
190 	char *name;
191 #endif
192 {
193 	static au_event_ent_t au_event_entry;
194 	static char	ename[AU_EVENT_NAME_MAX];
195 	static char	edesc[AU_EVENT_DESC_MAX];
196 
197 	/* initialize au_event_entry structure */
198 	au_event_entry.ae_name = ename;
199 	au_event_entry.ae_desc = edesc;
200 
201 	return (getauevnam_r(&au_event_entry, name));
202 }
203 
204 au_event_ent_t *
205 #ifdef __STDC__
206 getauevnam_r(au_event_ent_t *e, char *name)
207 #else
208 getauevnam_r(e, name)
209 	au_event_ent_t &e;
210 	char *name;
211 #endif
212 {
213 	setauevent();
214 	while (getauevent_r(e) != NULL) {
215 		if (strcmp(e->ae_name, name) == 0) {
216 			endauevent();
217 			return (e);
218 		}
219 	}
220 	endauevent();
221 	return ((au_event_ent_t *)NULL);
222 }
223 
224 au_event_ent_t *
225 #ifdef __STDC__
226 getauevnum_r(au_event_ent_t *e, au_event_t event_number)
227 #else
228 getauevnum_r(e, event_number)
229 	au_event_ent_t *e;
230 	au_event_t event_number;
231 #endif
232 {
233 	setauevent();
234 	while (getauevent_r(e) != NULL) {
235 		if (e->ae_number == event_number) {
236 			endauevent();
237 			return (e);
238 		}
239 	}
240 	endauevent();
241 	return ((au_event_ent_t *)NULL);
242 }
243 
244 au_event_ent_t *
245 #ifdef __STDC__
246 getauevnum(au_event_t event_number)
247 #else
248 getauevnum(event_number)
249 	au_event_t event_number;
250 #endif
251 {
252 	static au_event_ent_t e;
253 	static char	ename[AU_EVENT_NAME_MAX];
254 	static char	edesc[AU_EVENT_DESC_MAX];
255 
256 	/* initialize au_event_entry structure */
257 	e.ae_name = ename;
258 	e.ae_desc = edesc;
259 
260 	return (getauevnum_r(&e, event_number));
261 }
262 
263 au_event_t
264 #ifdef __STDC__
265 getauevnonam(char *event_name)
266 #else
267 getauevnonam(event_name)
268 	char	*event_name;
269 #endif
270 {
271 	au_event_ent_t e;
272 	char ename[AU_EVENT_NAME_MAX];
273 	char edesc[AU_EVENT_DESC_MAX];
274 
275 	/* initialize au_event_entry structure */
276 	e.ae_name = ename;
277 	e.ae_desc = edesc;
278 
279 	if (getauevnam_r(&e, event_name) == (au_event_ent_t *)0) {
280 		return (-1);
281 	}
282 	return (e.ae_number);
283 }
284 
285 /*
286  * cacheauevent:
287  *	Read the entire audit_event file into memory.
288  *	Set a pointer to the requested entry in the cache
289  *	or a pointer to an invalid entry if the event number
290  *	is not known.
291  *
292  *	Return < 0, if error.
293  *	Return   0, if event number not in cache.
294  *	Return   1, if event number is in cache.
295  */
296 
297 int
298 #ifdef __STDC__
299 cacheauevent(au_event_ent_t **result, au_event_t event_number)
300 #else
301 cacheauevent(result, event_number)
302 	au_event_ent_t **result; /* set this pointer to an entry in the cache */
303 	au_event_t event_number; /* request this event number */
304 #endif
305 {
306 	static ushort_t	max; /* the highest event number in the file */
307 	static ushort_t	min; /* the lowest event number in the file */
308 	static int	invalid; /* 1+index of the highest event number */
309 	static au_event_ent_t **index_tbl;
310 	static au_event_ent_t **p_tbl;
311 	static int	called_once = 0;
312 
313 	char	line[AU_EVENT_LINE_MAX];
314 	int	lines = 0;
315 	FILE	*fp;
316 	au_event_ent_t *p_event;
317 	int	i, size;
318 	int	hit = 0;
319 	char	*s;
320 
321 	_mutex_lock(&mutex_eventcache);
322 	if (called_once == 0) {
323 
324 		/* Count number of lines in the events file */
325 		if ((fp = fopen(au_event_fname, "rF")) == NULL) {
326 			_mutex_unlock(&mutex_eventcache);
327 			return (-1);
328 		}
329 		while (fgets(line, AU_EVENT_LINE_MAX, fp) != NULL) {
330 			s = line + strspn(line, " \t\r\n");
331 			if ((*s == '\0') || (*s == '#')) {
332 				continue;
333 			}
334 			lines++;
335 		}
336 		(void) fclose(fp);
337 		size = lines;
338 
339 		/*
340 		 * Make an array in which each element in an entry in the
341 		 * events file.  Make the next to last element an invalid
342 		 * event.  Make the last element a NULL pointer.
343 		 */
344 
345 		p_tbl = calloc(lines + 1, sizeof (au_event_ent_t));
346 		if (p_tbl == NULL) {
347 			_mutex_unlock(&mutex_eventcache);
348 			return (-2);
349 		}
350 		lines = 0;
351 		max = 0;
352 		min = 65535;
353 		setauevent();
354 		while ((p_event = getauevent()) != NULL) {
355 			p_tbl[lines] = (au_event_ent_t *)
356 				malloc(sizeof (au_event_ent_t));
357 			if (p_tbl[lines] == NULL) {
358 				_mutex_unlock(&mutex_eventcache);
359 				return (-3);
360 			}
361 			p_tbl[lines]->ae_number = p_event->ae_number;
362 			p_tbl[lines]->ae_name   = strdup(p_event->ae_name);
363 			p_tbl[lines]->ae_desc   = strdup(p_event->ae_desc);
364 			p_tbl[lines]->ae_class  = p_event->ae_class;
365 #ifdef DEBUG2
366 			printevent(p_tbl[lines]);
367 #endif
368 			if ((ushort_t)p_event->ae_number > max) {
369 				max = p_event->ae_number;
370 			}
371 			if ((ushort_t)p_event->ae_number < min) {
372 				min = p_event->ae_number;
373 			}
374 			lines++;
375 		}
376 		endauevent();
377 		invalid = lines;
378 		p_tbl[invalid] = (au_event_ent_t *)
379 			malloc(sizeof (au_event_ent_t));
380 		if (p_tbl[invalid] == NULL) {
381 			_mutex_unlock(&mutex_eventcache);
382 			return (-4);
383 		}
384 		p_tbl[invalid]->ae_number = -1;
385 		p_tbl[invalid]->ae_name   = "invalid event number";
386 		p_tbl[invalid]->ae_desc   = p_tbl[invalid]->ae_name;
387 		p_tbl[invalid]->ae_class  = (au_class_t)-1;
388 
389 #ifdef DEBUG2
390 		for (i = 0; i < size; i++) {
391 			printf("%d:%s:%s:%d\n", p_tbl[i]->ae_number,
392 				p_tbl[i]->ae_name, p_tbl[i]->ae_desc,
393 				p_tbl[i]->ae_class);
394 		}
395 #endif
396 
397 		/* get space for the index_tbl */
398 		index_tbl = calloc(max+1, sizeof (au_event_ent_t *));
399 		if (index_tbl == NULL) {
400 			_mutex_unlock(&mutex_eventcache);
401 			return (-5);
402 		}
403 
404 		/* intialize the index_tbl to the invalid event number */
405 		for (i = 0; (ushort_t)i < max; i++) {
406 			index_tbl[i] = p_tbl[invalid];
407 		}
408 
409 		/* point each index_tbl element at the corresponding event */
410 		for (i = 0; i < size; i++) {
411 			index_tbl[(ushort_t)p_tbl[i]->ae_number] = p_tbl[i];
412 		}
413 
414 		called_once = 1;
415 
416 	}
417 
418 	if ((ushort_t)event_number > max || (ushort_t)event_number < min) {
419 		*result = index_tbl[invalid];
420 	} else {
421 		*result = index_tbl[(ushort_t)event_number];
422 		hit = 1;
423 	}
424 	_mutex_unlock(&mutex_eventcache);
425 	return (hit);
426 }
427 
428 
429 static au_class_t
430 flagstohex(char *flags)
431 {
432 	au_class_ent_t *p_class;
433 	au_class_t	hex = 0;
434 	char	*comma = ",";
435 	char	*s;
436 	char	*last;
437 
438 	s = strtok_r(flags, comma, &last);
439 	while (s != NULL) {
440 		if ((cacheauclassnam(&p_class, s)) < 0) {
441 			cacheauclass_failure = 1;
442 			return ((au_class_t)-1);
443 		}
444 		hex |= p_class->ac_class;
445 		s = strtok_r(NULL, comma, &last);
446 	}
447 	return (hex);
448 }
449 
450 
451 #ifdef DEBUG2
452 void
453 printevent(p_event)
454 au_event_ent_t *p_event;
455 {
456 	printf("%d:%s:%s:%d\n", p_event->ae_number, p_event->ae_name,
457 		p_event->ae_desc, p_event->ae_class);
458 	fflush(stdout);
459 }
460 
461 
462 #endif
463