1 /* Author : Joshua Brindle <jbrindle@tresys.com>
2  *	    Karl MacMillan <kmacmillan@tresys.com>
3  *          Jason Tang     <jtang@tresys.com>
4  *	Added support for binary policy modules
5  *
6  * Copyright (C) 2004 - 2005 Tresys Technology, LLC
7  *	This program is free software; you can redistribute it and/or modify
8  *  	it under the terms of the GNU General Public License as published by
9  *	the Free Software Foundation, version 2.
10  */
11 
12 #include <assert.h>
13 #include <stdarg.h>
14 #include <stdlib.h>
15 #include <string.h>
16 
17 #include <sepol/policydb/policydb.h>
18 #include <sepol/policydb/avrule_block.h>
19 #include <sepol/policydb/conditional.h>
20 
21 #include "queue.h"
22 #include "module_compiler.h"
23 
24 union stack_item_u {
25 	avrule_block_t *avrule;
26 	cond_list_t *cond_list;
27 };
28 
29 typedef struct scope_stack {
30 	union stack_item_u u;
31 	int type;		/* for above union: 1 = avrule block, 2 = conditional */
32 	avrule_decl_t *decl;	/* if in an avrule block, which
33 				 * declaration is current */
34 	avrule_t *last_avrule;
35 	int in_else;		/* if in an avrule block, within ELSE branch */
36 	int require_given;	/* 1 if this block had at least one require */
37 	struct scope_stack *parent, *child;
38 } scope_stack_t;
39 
40 extern policydb_t *policydbp;
41 extern queue_t id_queue;
42 extern int yyerror(const char *msg);
43 __attribute__ ((format(printf, 1, 2)))
44 extern void yyerror2(const char *fmt, ...);
45 
46 static int push_stack(int stack_type, ...);
47 static void pop_stack(void);
48 
49 /* keep track of the last item added to the stack */
50 static scope_stack_t *stack_top = NULL;
51 static avrule_block_t *last_block;
52 static uint32_t next_decl_id = 1;
53 
define_policy(int pass,int module_header_given)54 int define_policy(int pass, int module_header_given)
55 {
56 	char *id;
57 
58 	if (module_header_given) {
59 		if (policydbp->policy_type != POLICY_MOD) {
60 			yyerror
61 			    ("Module specification found while not building a policy module.\n");
62 			return -1;
63 		}
64 
65 		if (pass == 2) {
66 			while ((id = queue_remove(id_queue)) != NULL)
67 				free(id);
68 		} else {
69 			id = (char *)queue_remove(id_queue);
70 			if (!id) {
71 				yyerror("no module name");
72 				return -1;
73 			}
74 			policydbp->name = id;
75 			if ((policydbp->version =
76 			     queue_remove(id_queue)) == NULL) {
77 				yyerror
78 				    ("Expected a module version but none was found.");
79 				return -1;
80 			}
81 		}
82 	} else {
83 		if (policydbp->policy_type == POLICY_MOD) {
84 			yyerror
85 			    ("Building a policy module, but no module specification found.\n");
86 			return -1;
87 		}
88 	}
89 	/* the first declaration within the global avrule
90 	   block will always have an id of 1 */
91 	next_decl_id = 2;
92 
93 	/* reset the scoping stack */
94 	while (stack_top != NULL) {
95 		pop_stack();
96 	}
97 	if (push_stack(1, policydbp->global, policydbp->global->branch_list) ==
98 	    -1) {
99 		return -1;
100 	}
101 	last_block = policydbp->global;
102 	return 0;
103 }
104 
105 /* Given the current parse stack, returns 1 if a declaration would be
106  * allowed here or 0 if not.  For example, declarations are not
107  * allowed in conditionals, so if there are any conditionals in the
108  * current scope stack then this would return a 0.
109  */
is_declaration_allowed(void)110 static int is_declaration_allowed(void)
111 {
112 	if (stack_top->type != 1 || stack_top->in_else) {
113 		return 0;
114 	}
115 	return 1;
116 }
117 
118 /* Attempt to declare a symbol within the current declaration.  If
119  * currently within a non-conditional and in a non-else branch then
120  * insert the symbol, return 0 on success if symbol was undeclared.
121  * For roles and users, it is legal to have multiple declarations; as
122  * such return 1 to indicate that caller must free() the datum because
123  * it was not added.  If symbols may not be declared here return -1.
124  * For duplicate declarations return -2.  For all else, including out
125  * of memory, return -3.  Note that dest_value and datum_value might
126  * not be restricted pointers. */
declare_symbol(uint32_t symbol_type,hashtab_key_t key,hashtab_datum_t datum,uint32_t * dest_value,uint32_t * datum_value)127 int declare_symbol(uint32_t symbol_type,
128 		   hashtab_key_t key, hashtab_datum_t datum,
129 		   uint32_t * dest_value, uint32_t * datum_value)
130 {
131 	avrule_decl_t *decl = stack_top->decl;
132 	int retval;
133 
134 	/* first check that symbols may be declared here */
135 	if (!is_declaration_allowed()) {
136 		return -1;
137 	}
138 	retval = symtab_insert(policydbp, symbol_type, key, datum,
139 			       SCOPE_DECL, decl->decl_id, dest_value);
140 	if (retval == 1 && dest_value) {
141 		symtab_datum_t *s =
142 		    (symtab_datum_t *) hashtab_search(policydbp->
143 						      symtab[symbol_type].table,
144 						      key);
145 		assert(s != NULL);
146 
147 		if (symbol_type == SYM_LEVELS) {
148 			*dest_value = ((level_datum_t *)s)->level->sens;
149 		} else {
150 			*dest_value = s->value;
151 		}
152 	} else if (retval == -2) {
153 		return -2;
154 	} else if (retval < 0) {
155 		return -3;
156 	} else {		/* fall through possible if retval is 0 */
157 	}
158 	if (datum_value != NULL) {
159 		if (ebitmap_set_bit(decl->declared.scope + symbol_type,
160 				    *datum_value - 1, 1)) {
161 			return -3;
162 		}
163 	}
164 	return retval;
165 }
166 
role_implicit_bounds(hashtab_t roles_tab,char * role_id,role_datum_t * role)167 static int role_implicit_bounds(hashtab_t roles_tab,
168 				char *role_id, role_datum_t *role)
169 {
170 	role_datum_t *bounds;
171 	char *bounds_id, *delim;
172 
173 	delim = strrchr(role_id, '.');
174 	if (!delim)
175 		return 0;	/* no implicit boundary */
176 
177 	bounds_id = strdup(role_id);
178 	if (!bounds_id) {
179 		yyerror("out of memory");
180 		return -1;
181 	}
182 	bounds_id[(size_t)(delim - role_id)] = '\0';
183 
184 	bounds = hashtab_search(roles_tab, bounds_id);
185 	if (!bounds) {
186 		yyerror2("role %s doesn't exist, is implicit bounds of %s",
187 			 bounds_id, role_id);
188 		return -1;
189 	}
190 
191 	if (!role->bounds)
192 		role->bounds = bounds->s.value;
193 	else if (role->bounds != bounds->s.value) {
194 		yyerror2("role %s has inconsistent bounds %s/%s",
195 			 role_id, bounds_id,
196 			 policydbp->p_role_val_to_name[role->bounds - 1]);
197 		return -1;
198 	}
199 	free(bounds_id);
200 
201 	return 0;
202 }
203 
declare_role(unsigned char isattr)204 role_datum_t *declare_role(unsigned char isattr)
205 {
206 	char *id = queue_remove(id_queue), *dest_id = NULL;
207 	role_datum_t *role = NULL, *dest_role = NULL;
208 	int retval;
209 	uint32_t value;
210 
211 	if (id == NULL) {
212 		yyerror("no role name");
213 		return NULL;
214 	}
215 	if ((role = (role_datum_t *) malloc(sizeof(*role))) == NULL) {
216 		yyerror("Out of memory!");
217 		free(id);
218 		return NULL;
219 	}
220 	role_datum_init(role);
221 	role->flavor = isattr ? ROLE_ATTRIB : ROLE_ROLE;
222 	retval =
223 	    declare_symbol(SYM_ROLES, id, (hashtab_datum_t *) role, &value,
224 			   &value);
225 	if (retval == 0) {
226 		role->s.value = value;
227 		if ((dest_id = strdup(id)) == NULL) {
228 			yyerror("Out of memory!");
229 			return NULL;
230 		}
231 	} else {
232 		/* this role was already declared in this module, or error */
233 		dest_id = id;
234 		role_datum_destroy(role);
235 		free(role);
236 	}
237 	if (retval == 0 || retval == 1) {
238 		/* create a new role_datum_t for this decl, if necessary */
239 		hashtab_t roles_tab;
240 		assert(stack_top->type == 1);
241 		if (stack_top->parent == NULL) {
242 			/* in parent, so use global symbol table */
243 			roles_tab = policydbp->p_roles.table;
244 		} else {
245 			roles_tab = stack_top->decl->p_roles.table;
246 		}
247 		dest_role = (role_datum_t *) hashtab_search(roles_tab, dest_id);
248 		if (dest_role == NULL) {
249 			if ((dest_role =
250 			     (role_datum_t *) malloc(sizeof(*dest_role))) ==
251 			    NULL) {
252 				yyerror("Out of memory!");
253 				free(dest_id);
254 				return NULL;
255 			}
256 			role_datum_init(dest_role);
257 			dest_role->s.value = value;
258 			dest_role->flavor = isattr ? ROLE_ATTRIB : ROLE_ROLE;
259 			if (role_implicit_bounds(roles_tab, dest_id, dest_role)) {
260 				free(dest_id);
261 				role_datum_destroy(dest_role);
262 				free(dest_role);
263 				return NULL;
264 			}
265 			if (hashtab_insert(roles_tab, dest_id, dest_role)) {
266 				yyerror("Out of memory!");
267 				free(dest_id);
268 				role_datum_destroy(dest_role);
269 				free(dest_role);
270 				return NULL;
271 			}
272 		} else {
273 			free(dest_id);
274 		}
275 	} else {
276 		free(dest_id);
277 	}
278 	switch (retval) {
279 	case -3:{
280 			yyerror("Out of memory!");
281 			return NULL;
282 		}
283 	case -2:{
284 			yyerror("duplicate declaration of role");
285 			return NULL;
286 		}
287 	case -1:{
288 			yyerror("could not declare role here");
289 			return NULL;
290 		}
291 	case 0:{
292 			if (ebitmap_set_bit
293 			    (&dest_role->dominates, role->s.value - 1, 1)) {
294 				yyerror("out of memory");
295 				return NULL;
296 			}
297 			return dest_role;
298 		}
299 	case 1:{
300 			return dest_role;	/* role already declared for this block */
301 		}
302 	default:{
303 			abort();	/* should never get here */
304 		}
305 	}
306 }
307 
declare_type(unsigned char primary,unsigned char isattr)308 type_datum_t *declare_type(unsigned char primary, unsigned char isattr)
309 {
310 	char *id;
311 	type_datum_t *typdatum;
312 	int retval;
313 	uint32_t value = 0;
314 
315 	id = (char *)queue_remove(id_queue);
316 	if (!id) {
317 		yyerror("no type/attribute name?");
318 		return NULL;
319 	}
320 	if (strcmp(id, "self") == 0) {
321 		yyerror
322 		    ("'self' is a reserved type name and may not be declared.");
323 		free(id);
324 		return NULL;
325 	}
326 
327 	typdatum = (type_datum_t *) malloc(sizeof(type_datum_t));
328 	if (!typdatum) {
329 		yyerror("Out of memory!");
330 		free(id);
331 		return NULL;
332 	}
333 	type_datum_init(typdatum);
334 	typdatum->primary = primary;
335 	typdatum->flavor = isattr ? TYPE_ATTRIB : TYPE_TYPE;
336 
337 	retval = declare_symbol(SYM_TYPES, id, typdatum, &value, &value);
338 	if (retval == 0 || retval == 1) {
339 		if (typdatum->primary) {
340 			typdatum->s.value = value;
341 		}
342 	} else {
343 		/* error occurred (can't have duplicate type declarations) */
344 		free(id);
345 		type_datum_destroy(typdatum);
346 		free(typdatum);
347 	}
348 	switch (retval) {
349 	case -3:{
350 			yyerror("Out of memory!");
351 			return NULL;
352 		}
353 	case -2:{
354 			yyerror2("duplicate declaration of type/attribute");
355 			return NULL;
356 		}
357 	case -1:{
358 			yyerror("could not declare type/attribute here");
359 			return NULL;
360 		}
361 	case 0:
362 	case 1:{
363 			return typdatum;
364 		}
365 	default:{
366 			abort();	/* should never get here */
367 		}
368 	}
369 }
370 
user_implicit_bounds(hashtab_t users_tab,char * user_id,user_datum_t * user)371 static int user_implicit_bounds(hashtab_t users_tab,
372 				char *user_id, user_datum_t *user)
373 {
374 	user_datum_t *bounds;
375 	char *bounds_id, *delim;
376 
377 	delim = strrchr(user_id, '.');
378 	if (!delim)
379 		return 0;	/* no implicit boundary */
380 
381 	bounds_id = strdup(user_id);
382 	if (!bounds_id) {
383 		yyerror("out of memory");
384 		return -1;
385 	}
386 	bounds_id[(size_t)(delim - user_id)] = '\0';
387 
388 	bounds = hashtab_search(users_tab, bounds_id);
389 	if (!bounds) {
390 		yyerror2("user %s doesn't exist, is implicit bounds of %s",
391 			 bounds_id, user_id);
392 		return -1;
393 	}
394 
395 	if (!user->bounds)
396 		user->bounds = bounds->s.value;
397 	else if (user->bounds != bounds->s.value) {
398 		yyerror2("user %s has inconsistent bounds %s/%s",
399 			 user_id, bounds_id,
400 			 policydbp->p_role_val_to_name[user->bounds - 1]);
401 		return -1;
402 	}
403 	free(bounds_id);
404 
405 	return 0;
406 }
407 
declare_user(void)408 user_datum_t *declare_user(void)
409 {
410 	char *id = queue_remove(id_queue), *dest_id = NULL;
411 	user_datum_t *user = NULL, *dest_user = NULL;
412 	int retval;
413 	uint32_t value = 0;
414 
415 	if (id == NULL) {
416 		yyerror("no user name");
417 		return NULL;
418 	}
419 	if ((user = (user_datum_t *) malloc(sizeof(*user))) == NULL) {
420 		yyerror("Out of memory!");
421 		free(id);
422 		return NULL;
423 	}
424 	user_datum_init(user);
425 
426 	retval =
427 	    declare_symbol(SYM_USERS, id, (hashtab_datum_t *) user, &value,
428 			   &value);
429 
430 	if (retval == 0) {
431 		user->s.value = value;
432 		if ((dest_id = strdup(id)) == NULL) {
433 			yyerror("Out of memory!");
434 			return NULL;
435 		}
436 	} else {
437 		/* this user was already declared in this module, or error */
438 		dest_id = id;
439 		user_datum_destroy(user);
440 		free(user);
441 	}
442 	if (retval == 0 || retval == 1) {
443 		/* create a new user_datum_t for this decl, if necessary */
444 		hashtab_t users_tab;
445 		assert(stack_top->type == 1);
446 		if (stack_top->parent == NULL) {
447 			/* in parent, so use global symbol table */
448 			users_tab = policydbp->p_users.table;
449 		} else {
450 			users_tab = stack_top->decl->p_users.table;
451 		}
452 		dest_user = (user_datum_t *) hashtab_search(users_tab, dest_id);
453 		if (dest_user == NULL) {
454 			if ((dest_user =
455 			     (user_datum_t *) malloc(sizeof(*dest_user))) ==
456 			    NULL) {
457 				yyerror("Out of memory!");
458 				free(dest_id);
459 				return NULL;
460 			}
461 			user_datum_init(dest_user);
462 			dest_user->s.value = value;
463 			if (user_implicit_bounds(users_tab, dest_id, dest_user)) {
464 				free(dest_id);
465 				user_datum_destroy(dest_user);
466 				free(dest_user);
467 				return NULL;
468 			}
469 			if (hashtab_insert(users_tab, dest_id, dest_user)) {
470 				yyerror("Out of memory!");
471 				free(dest_id);
472 				user_datum_destroy(dest_user);
473 				free(dest_user);
474 				return NULL;
475 			}
476 		} else {
477 			free(dest_id);
478 		}
479 	} else {
480 		free(dest_id);
481 	}
482 	switch (retval) {
483 	case -3:{
484 			yyerror("Out of memory!");
485 			return NULL;
486 		}
487 	case -2:{
488 			yyerror("duplicate declaration of user");
489 			return NULL;
490 		}
491 	case -1:{
492 			yyerror("could not declare user here");
493 			return NULL;
494 		}
495 	case 0:{
496 			return dest_user;
497 		}
498 	case 1:{
499 			return dest_user;	/* user already declared for this block */
500 		}
501 	default:{
502 			abort();	/* should never get here */
503 		}
504 	}
505 }
506 
507 /* Return a type_datum_t for the local avrule_decl with the given ID.
508  * If it does not exist, create one with the same value as 'value'.
509  * This function assumes that the ID is within scope.  c.f.,
510  * is_id_in_scope().
511  *
512  * NOTE: this function usurps ownership of id afterwards.  The caller
513  * shall not reference it nor free() it afterwards.
514  */
get_local_type(char * id,uint32_t value,unsigned char isattr)515 type_datum_t *get_local_type(char *id, uint32_t value, unsigned char isattr)
516 {
517 	type_datum_t *dest_typdatum;
518 	hashtab_t types_tab;
519 	assert(stack_top->type == 1);
520 	if (stack_top->parent == NULL) {
521 		/* in global, so use global symbol table */
522 		types_tab = policydbp->p_types.table;
523 	} else {
524 		types_tab = stack_top->decl->p_types.table;
525 	}
526 	dest_typdatum = hashtab_search(types_tab, id);
527 	if (!dest_typdatum) {
528 		dest_typdatum = (type_datum_t *) malloc(sizeof(type_datum_t));
529 		if (dest_typdatum == NULL) {
530 			free(id);
531 			return NULL;
532 		}
533 		type_datum_init(dest_typdatum);
534 		dest_typdatum->s.value = value;
535 		dest_typdatum->flavor = isattr ? TYPE_ATTRIB : TYPE_TYPE;
536 		dest_typdatum->primary = 1;
537 		if (hashtab_insert(types_tab, id, dest_typdatum)) {
538 			free(id);
539 			type_datum_destroy(dest_typdatum);
540 			free(dest_typdatum);
541 			return NULL;
542 		}
543 
544 	} else {
545 		free(id);
546 		if (dest_typdatum->flavor != isattr ? TYPE_ATTRIB : TYPE_TYPE) {
547 			return NULL;
548 		}
549 	}
550 	return dest_typdatum;
551 }
552 
553 /* Return a role_datum_t for the local avrule_decl with the given ID.
554  * If it does not exist, create one with the same value as 'value'.
555  * This function assumes that the ID is within scope.  c.f.,
556  * is_id_in_scope().
557  *
558  * NOTE: this function usurps ownership of id afterwards.  The caller
559  * shall not reference it nor free() it afterwards.
560  */
get_local_role(char * id,uint32_t value,unsigned char isattr)561 role_datum_t *get_local_role(char *id, uint32_t value, unsigned char isattr)
562 {
563 	role_datum_t *dest_roledatum;
564 	hashtab_t roles_tab;
565 
566 	assert(stack_top->type == 1);
567 
568 	if (stack_top->parent == NULL) {
569 		/* in global, so use global symbol table */
570 		roles_tab = policydbp->p_roles.table;
571 	} else {
572 		roles_tab = stack_top->decl->p_roles.table;
573 	}
574 
575 	dest_roledatum = hashtab_search(roles_tab, id);
576 	if (!dest_roledatum) {
577 		dest_roledatum = (role_datum_t *)malloc(sizeof(role_datum_t));
578 		if (dest_roledatum == NULL) {
579 			free(id);
580 			return NULL;
581 		}
582 
583 		role_datum_init(dest_roledatum);
584 		dest_roledatum->s.value = value;
585 		dest_roledatum->flavor = isattr ? ROLE_ATTRIB : ROLE_ROLE;
586 
587 		if (hashtab_insert(roles_tab, id, dest_roledatum)) {
588 			free(id);
589 			role_datum_destroy(dest_roledatum);
590 			free(dest_roledatum);
591 			return NULL;
592 		}
593 	} else {
594 		free(id);
595 		if (dest_roledatum->flavor != isattr ? ROLE_ATTRIB : ROLE_ROLE)
596 			return NULL;
597 	}
598 
599 	return dest_roledatum;
600 }
601 
602 /* Given the current parse stack, returns 1 if a requirement would be
603  * allowed here or 0 if not.  For example, the ELSE branch may never
604  * have its own requirements.
605  */
is_require_allowed(void)606 static int is_require_allowed(void)
607 {
608 	if (stack_top->type == 1 && !stack_top->in_else) {
609 		return 1;
610 	}
611 	return 0;
612 }
613 
614 /* Attempt to require a symbol within the current scope.  If currently
615  * within an optional (and not its else branch), add the symbol to the
616  * required list.  Return 0 on success, 1 if caller needs to free()
617  * datum.  If symbols may not be declared here return -1.  For duplicate
618  * declarations return -2.  For all else, including out of memory,
619  * return -3..  Note that dest_value and datum_value might not be
620  * restricted pointers.
621  */
require_symbol(uint32_t symbol_type,hashtab_key_t key,hashtab_datum_t datum,uint32_t * dest_value,uint32_t * datum_value)622 int require_symbol(uint32_t symbol_type,
623 		   hashtab_key_t key, hashtab_datum_t datum,
624 		   uint32_t * dest_value, uint32_t * datum_value)
625 {
626 	avrule_decl_t *decl = stack_top->decl;
627 	int retval;
628 
629 	/* first check that symbols may be required here */
630 	if (!is_require_allowed()) {
631 		return -1;
632 	}
633 	retval = symtab_insert(policydbp, symbol_type, key, datum,
634 			       SCOPE_REQ, decl->decl_id, dest_value);
635 	if (retval == 1) {
636 		symtab_datum_t *s =
637 		    (symtab_datum_t *) hashtab_search(policydbp->
638 						      symtab[symbol_type].table,
639 						      key);
640 		assert(s != NULL);
641 
642 		if (symbol_type == SYM_LEVELS) {
643 			*dest_value = ((level_datum_t *)s)->level->sens;
644 		} else {
645 			*dest_value = s->value;
646 		}
647 	} else if (retval == -2) {
648 		/* ignore require statements if that symbol was
649 		 * previously declared and is in current scope */
650 		int prev_declaration_ok = 0;
651 		if (is_id_in_scope(symbol_type, key)) {
652 			if (symbol_type == SYM_TYPES) {
653 				/* check that previous symbol has same
654 				 * type/attribute-ness */
655 				unsigned char new_isattr =
656 				    ((type_datum_t *) datum)->flavor;
657 				type_datum_t *old_datum =
658 				    (type_datum_t *) hashtab_search(policydbp->
659 								    symtab
660 								    [SYM_TYPES].
661 								    table, key);
662 				assert(old_datum != NULL);
663 				unsigned char old_isattr = old_datum->flavor;
664 				prev_declaration_ok =
665 				    (old_isattr == new_isattr ? 1 : 0);
666 			} else {
667 				prev_declaration_ok = 1;
668 			}
669 		}
670 		if (prev_declaration_ok) {
671 			/* ignore this require statement because it
672 			 * was already declared within my scope */
673 			stack_top->require_given = 1;
674 			return 1;
675 		} else {
676 			/* previous declaration was not in scope or
677 			 * had a mismatched type/attribute, so
678 			 * generate an error */
679 			return -2;
680 		}
681 	} else if (retval < 0) {
682 		return -3;
683 	} else {		/* fall through possible if retval is 0 or 1 */
684 	}
685 	if (datum_value != NULL) {
686 		if (ebitmap_set_bit(decl->required.scope + symbol_type,
687 				    *datum_value - 1, 1)) {
688 			return -3;
689 		}
690 	}
691 	stack_top->require_given = 1;
692 	return retval;
693 }
694 
add_perm_to_class(uint32_t perm_value,uint32_t class_value)695 int add_perm_to_class(uint32_t perm_value, uint32_t class_value)
696 {
697 	avrule_decl_t *decl = stack_top->decl;
698 	scope_index_t *scope;
699 
700 	assert(perm_value >= 1);
701 	assert(class_value >= 1);
702 	scope = &decl->required;
703 	if (class_value > scope->class_perms_len) {
704 		uint32_t i;
705 		ebitmap_t *new_map = realloc(scope->class_perms_map,
706 					     class_value * sizeof(*new_map));
707 		if (new_map == NULL) {
708 			return -1;
709 		}
710 		scope->class_perms_map = new_map;
711 		for (i = scope->class_perms_len; i < class_value; i++) {
712 			ebitmap_init(scope->class_perms_map + i);
713 		}
714 		scope->class_perms_len = class_value;
715 	}
716 	if (ebitmap_set_bit(scope->class_perms_map + class_value - 1,
717 			    perm_value - 1, 1)) {
718 		return -1;
719 	}
720 	return 0;
721 }
722 
perm_destroy(hashtab_key_t key,hashtab_datum_t datum,void * p)723 static int perm_destroy(hashtab_key_t key, hashtab_datum_t datum, void *p
724 			__attribute__ ((unused)))
725 {
726 	if (key)
727 		free(key);
728 	free(datum);
729 	return 0;
730 }
731 
class_datum_destroy(class_datum_t * cladatum)732 static void class_datum_destroy(class_datum_t * cladatum)
733 {
734 	if (cladatum != NULL) {
735 		hashtab_map(cladatum->permissions.table, perm_destroy, NULL);
736 		hashtab_destroy(cladatum->permissions.table);
737 		free(cladatum);
738 	}
739 }
740 
require_class(int pass)741 int require_class(int pass)
742 {
743 	char *class_id = queue_remove(id_queue);
744 	char *perm_id = NULL;
745 	class_datum_t *datum = NULL;
746 	perm_datum_t *perm = NULL;
747 	int ret;
748 
749 	if (pass == 2) {
750 		free(class_id);
751 		while ((perm_id = queue_remove(id_queue)) != NULL)
752 			free(perm_id);
753 		return 0;
754 	}
755 
756 	/* first add the class if it is not already there */
757 	if (class_id == NULL) {
758 		yyerror("no class name for class definition?");
759 		return -1;
760 	}
761 
762 	if ((datum = calloc(1, sizeof(*datum))) == NULL ||
763 	    symtab_init(&datum->permissions, PERM_SYMTAB_SIZE)) {
764 		yyerror("Out of memory!");
765 		goto cleanup;
766 	}
767 	ret =
768 	    require_symbol(SYM_CLASSES, class_id, datum, &datum->s.value,
769 			   &datum->s.value);
770 	switch (ret) {
771 	case -3:{
772 			yyerror("Out of memory!");
773 			free(class_id);
774 			class_datum_destroy(datum);
775 			goto cleanup;
776 		}
777 	case -2:{
778 			yyerror("duplicate declaration of class");
779 			free(class_id);
780 			class_datum_destroy(datum);
781 			goto cleanup;
782 		}
783 	case -1:{
784 			yyerror("could not require class here");
785 			free(class_id);
786 			class_datum_destroy(datum);
787 			goto cleanup;
788 		}
789 	case 0:{
790 			/* a new class was added; reindex everything */
791 			if (policydb_index_classes(policydbp)) {
792 				yyerror("Out of memory!");
793 				goto cleanup;
794 			}
795 			break;
796 		}
797 	case 1:{
798 			class_datum_destroy(datum);
799 			datum =
800 			    hashtab_search(policydbp->p_classes.table,
801 					   class_id);
802 			assert(datum);	/* the class datum should have existed */
803 			free(class_id);
804 			break;
805 		}
806 	default:{
807 			abort();	/* should never get here */
808 		}
809 	}
810 
811 	/* now add each of the permissions to this class's requirements */
812 	while ((perm_id = queue_remove(id_queue)) != NULL) {
813 		int allocated = 0;
814 
815 		/* Is the permission already in the table? */
816 		perm = hashtab_search(datum->permissions.table, perm_id);
817 		if (!perm && datum->comdatum)
818 			perm =
819 			    hashtab_search(datum->comdatum->permissions.table,
820 					   perm_id);
821 		if (perm) {
822 			/* Yes, drop the name. */
823 			free(perm_id);
824 		} else {
825 			/* No - allocate and insert an entry for it. */
826 			if (policydbp->policy_type == POLICY_BASE) {
827 				yyerror2
828 				    ("Base policy - require of permission %s without prior declaration.",
829 				     perm_id);
830 				free(perm_id);
831 				goto cleanup;
832 			}
833 			allocated = 1;
834 			if ((perm = malloc(sizeof(*perm))) == NULL) {
835 				yyerror("Out of memory!");
836 				free(perm_id);
837 				goto cleanup;
838 			}
839 			memset(perm, 0, sizeof(*perm));
840 			ret =
841 			    hashtab_insert(datum->permissions.table, perm_id,
842 					   perm);
843 			if (ret) {
844 				yyerror("Out of memory!");
845 				free(perm_id);
846 				free(perm);
847 				goto cleanup;
848 			}
849 			perm->s.value = datum->permissions.nprim + 1;
850 		}
851 
852 		if (add_perm_to_class(perm->s.value, datum->s.value) == -1) {
853 			yyerror("Out of memory!");
854 			goto cleanup;
855 		}
856 
857 		/* Update number of primitives if we allocated one. */
858 		if (allocated)
859 			datum->permissions.nprim++;
860 	}
861 	return 0;
862       cleanup:
863 	return -1;
864 }
865 
require_role_or_attribute(int pass,unsigned char isattr)866 static int require_role_or_attribute(int pass, unsigned char isattr)
867 {
868 	char *id = queue_remove(id_queue);
869 	role_datum_t *role = NULL;
870 	int retval;
871 	if (pass == 2) {
872 		free(id);
873 		return 0;
874 	}
875 	if (id == NULL) {
876 		yyerror("no role name");
877 		return -1;
878 	}
879 	if ((role = malloc(sizeof(*role))) == NULL) {
880 		free(id);
881 		yyerror("Out of memory!");
882 		return -1;
883 	}
884 	role_datum_init(role);
885 	role->flavor = isattr ? ROLE_ATTRIB : ROLE_ROLE;
886 	retval =
887 	    require_symbol(SYM_ROLES, id, (hashtab_datum_t *) role,
888 			   &role->s.value, &role->s.value);
889 	if (retval != 0) {
890 		free(id);
891 		role_datum_destroy(role);
892 		free(role);
893 	}
894 	switch (retval) {
895 	case -3:{
896 			yyerror("Out of memory!");
897 			return -1;
898 		}
899 	case -2:{
900 			yyerror("duplicate declaration of role");
901 			return -1;
902 		}
903 	case -1:{
904 			yyerror("could not require role here");
905 			return -1;
906 		}
907 	case 0:{
908 			/* all roles dominate themselves */
909 			if (ebitmap_set_bit
910 			    (&role->dominates, role->s.value - 1, 1)) {
911 				yyerror("Out of memory");
912 				return -1;
913 			}
914 			return 0;
915 		}
916 	case 1:{
917 			return 0;	/* role already required */
918 		}
919 	default:{
920 			abort();	/* should never get here */
921 		}
922 	}
923 }
924 
require_role(int pass)925 int require_role(int pass)
926 {
927 	return require_role_or_attribute(pass, 0);
928 }
929 
require_attribute_role(int pass)930 int require_attribute_role(int pass)
931 {
932 	return require_role_or_attribute(pass, 1);
933 }
934 
require_type_or_attribute(int pass,unsigned char isattr)935 static int require_type_or_attribute(int pass, unsigned char isattr)
936 {
937 	char *id = queue_remove(id_queue);
938 	type_datum_t *type = NULL;
939 	int retval;
940 	if (pass == 2) {
941 		free(id);
942 		return 0;
943 	}
944 	if (id == NULL) {
945 		yyerror("no type name");
946 		return -1;
947 	}
948 	if ((type = malloc(sizeof(*type))) == NULL) {
949 		free(id);
950 		yyerror("Out of memory!");
951 		return -1;
952 	}
953 	type_datum_init(type);
954 	type->primary = 1;
955 	type->flavor = isattr ? TYPE_ATTRIB : TYPE_TYPE;
956 	retval =
957 	    require_symbol(SYM_TYPES, id, (hashtab_datum_t *) type,
958 			   &type->s.value, &type->s.value);
959 	if (retval != 0) {
960 		free(id);
961 		free(type);
962 	}
963 	switch (retval) {
964 	case -3:{
965 			yyerror("Out of memory!");
966 			return -1;
967 		}
968 	case -2:{
969 			yyerror("duplicate declaration of type/attribute");
970 			return -1;
971 		}
972 	case -1:{
973 			yyerror("could not require type/attribute here");
974 			return -1;
975 		}
976 	case 0:{
977 			return 0;
978 		}
979 	case 1:{
980 			return 0;	/* type already required */
981 		}
982 	default:{
983 			abort();	/* should never get here */
984 		}
985 	}
986 }
987 
require_type(int pass)988 int require_type(int pass)
989 {
990 	return require_type_or_attribute(pass, 0);
991 }
992 
require_attribute(int pass)993 int require_attribute(int pass)
994 {
995 	return require_type_or_attribute(pass, 1);
996 }
997 
require_user(int pass)998 int require_user(int pass)
999 {
1000 	char *id = queue_remove(id_queue);
1001 	user_datum_t *user = NULL;
1002 	int retval;
1003 	if (pass == 1) {
1004 		free(id);
1005 		return 0;
1006 	}
1007 	if (id == NULL) {
1008 		yyerror("no user name");
1009 		return -1;
1010 	}
1011 	if ((user = malloc(sizeof(*user))) == NULL) {
1012 		free(id);
1013 		yyerror("Out of memory!");
1014 		return -1;
1015 	}
1016 	user_datum_init(user);
1017 	retval =
1018 	    require_symbol(SYM_USERS, id, (hashtab_datum_t *) user,
1019 			   &user->s.value, &user->s.value);
1020 	if (retval != 0) {
1021 		free(id);
1022 		user_datum_destroy(user);
1023 	}
1024 	switch (retval) {
1025 	case -3:{
1026 			yyerror("Out of memory!");
1027 			return -1;
1028 		}
1029 	case -2:{
1030 			yyerror("duplicate declaration of user");
1031 			return -1;
1032 		}
1033 	case -1:{
1034 			yyerror("could not require user here");
1035 			return -1;
1036 		}
1037 	case 0:{
1038 			return 0;
1039 		}
1040 	case 1:{
1041 			return 0;	/* user already required */
1042 		}
1043 	default:{
1044 			abort();	/* should never get here */
1045 		}
1046 	}
1047 }
1048 
require_bool_tunable(int pass,int is_tunable)1049 static int require_bool_tunable(int pass, int is_tunable)
1050 {
1051 	char *id = queue_remove(id_queue);
1052 	cond_bool_datum_t *booldatum = NULL;
1053 	int retval;
1054 	if (pass == 2) {
1055 		free(id);
1056 		return 0;
1057 	}
1058 	if (id == NULL) {
1059 		yyerror("no boolean name");
1060 		return -1;
1061 	}
1062 	if ((booldatum = calloc(1, sizeof(*booldatum))) == NULL) {
1063 		cond_destroy_bool(id, booldatum, NULL);
1064 		yyerror("Out of memory!");
1065 		return -1;
1066 	}
1067 	if (is_tunable)
1068 		booldatum->flags |= COND_BOOL_FLAGS_TUNABLE;
1069 	retval =
1070 	    require_symbol(SYM_BOOLS, id, (hashtab_datum_t *) booldatum,
1071 			   &booldatum->s.value, &booldatum->s.value);
1072 	if (retval != 0) {
1073 		cond_destroy_bool(id, booldatum, NULL);
1074 	}
1075 	switch (retval) {
1076 	case -3:{
1077 			yyerror("Out of memory!");
1078 			return -1;
1079 		}
1080 	case -2:{
1081 			yyerror("duplicate declaration of boolean");
1082 			return -1;
1083 		}
1084 	case -1:{
1085 			yyerror("could not require boolean here");
1086 			return -1;
1087 		}
1088 	case 0:{
1089 			return 0;
1090 		}
1091 	case 1:{
1092 			return 0;	/* boolean already required */
1093 		}
1094 	default:{
1095 			abort();	/* should never get here */
1096 		}
1097 	}
1098 }
1099 
require_bool(int pass)1100 int require_bool(int pass)
1101 {
1102 	return require_bool_tunable(pass, 0);
1103 }
1104 
require_tunable(int pass)1105 int require_tunable(int pass)
1106 {
1107 	return require_bool_tunable(pass, 1);
1108 }
1109 
require_sens(int pass)1110 int require_sens(int pass)
1111 {
1112 	char *id = queue_remove(id_queue);
1113 	level_datum_t *level = NULL;
1114 	int retval;
1115 	if (pass == 2) {
1116 		free(id);
1117 		return 0;
1118 	}
1119 	if (!id) {
1120 		yyerror("no sensitivity name");
1121 		return -1;
1122 	}
1123 	level = malloc(sizeof(level_datum_t));
1124 	if (!level) {
1125 		free(id);
1126 		yyerror("Out of memory!");
1127 		return -1;
1128 	}
1129 	level_datum_init(level);
1130 	level->level = malloc(sizeof(mls_level_t));
1131 	if (!level->level) {
1132 		free(id);
1133 		level_datum_destroy(level);
1134 		free(level);
1135 		yyerror("Out of memory!");
1136 		return -1;
1137 	}
1138 	mls_level_init(level->level);
1139 	retval = require_symbol(SYM_LEVELS, id, (hashtab_datum_t *) level,
1140 				&level->level->sens, &level->level->sens);
1141 	if (retval != 0) {
1142 		free(id);
1143 		mls_level_destroy(level->level);
1144 		free(level->level);
1145 		level_datum_destroy(level);
1146 		free(level);
1147 	}
1148 	switch (retval) {
1149 	case -3:{
1150 			yyerror("Out of memory!");
1151 			return -1;
1152 		}
1153 	case -2:{
1154 			yyerror("duplicate declaration of sensitivity");
1155 			return -1;
1156 		}
1157 	case -1:{
1158 			yyerror("could not require sensitivity here");
1159 			return -1;
1160 		}
1161 	case 0:{
1162 			return 0;
1163 		}
1164 	case 1:{
1165 			return 0;	/* sensitivity already required */
1166 		}
1167 	default:{
1168 			abort();	/* should never get here */
1169 		}
1170 	}
1171 }
1172 
require_cat(int pass)1173 int require_cat(int pass)
1174 {
1175 	char *id = queue_remove(id_queue);
1176 	cat_datum_t *cat = NULL;
1177 	int retval;
1178 	if (pass == 2) {
1179 		free(id);
1180 		return 0;
1181 	}
1182 	if (!id) {
1183 		yyerror("no category name");
1184 		return -1;
1185 	}
1186 	cat = malloc(sizeof(cat_datum_t));
1187 	if (!cat) {
1188 		free(id);
1189 		yyerror("Out of memory!");
1190 		return -1;
1191 	}
1192 	cat_datum_init(cat);
1193 
1194 	retval = require_symbol(SYM_CATS, id, (hashtab_datum_t *) cat,
1195 				&cat->s.value, &cat->s.value);
1196 	if (retval != 0) {
1197 		free(id);
1198 		cat_datum_destroy(cat);
1199 		free(cat);
1200 	}
1201 	switch (retval) {
1202 	case -3:{
1203 			yyerror("Out of memory!");
1204 			return -1;
1205 		}
1206 	case -2:{
1207 			yyerror("duplicate declaration of category");
1208 			return -1;
1209 		}
1210 	case -1:{
1211 			yyerror("could not require category here");
1212 			return -1;
1213 		}
1214 	case 0:{
1215 			return 0;
1216 		}
1217 	case 1:{
1218 			return 0;	/* category already required */
1219 		}
1220 	default:{
1221 			abort();	/* should never get here */
1222 		}
1223 	}
1224 }
1225 
is_scope_in_stack(scope_datum_t * scope,scope_stack_t * stack)1226 static int is_scope_in_stack(scope_datum_t * scope, scope_stack_t * stack)
1227 {
1228 	uint32_t i;
1229 	if (stack == NULL) {
1230 		return 0;	/* no matching scope found */
1231 	}
1232 	if (stack->type == 1) {
1233 		avrule_decl_t *decl = stack->decl;
1234 		for (i = 0; i < scope->decl_ids_len; i++) {
1235 			if (scope->decl_ids[i] == decl->decl_id) {
1236 				return 1;
1237 			}
1238 		}
1239 	} else {
1240 		/* note that conditionals can't declare or require
1241 		 * symbols, so skip this level */
1242 	}
1243 
1244 	/* not within scope of this stack, so try its parent */
1245 	return is_scope_in_stack(scope, stack->parent);
1246 }
1247 
is_id_in_scope(uint32_t symbol_type,hashtab_key_t id)1248 int is_id_in_scope(uint32_t symbol_type, hashtab_key_t id)
1249 {
1250 	scope_datum_t *scope =
1251 	    (scope_datum_t *) hashtab_search(policydbp->scope[symbol_type].
1252 					     table, id);
1253 	if (scope == NULL) {
1254 		return 1;	/* id is not known, so return success */
1255 	}
1256 	return is_scope_in_stack(scope, stack_top);
1257 }
1258 
is_perm_in_scope_index(uint32_t perm_value,uint32_t class_value,scope_index_t * scope)1259 static int is_perm_in_scope_index(uint32_t perm_value, uint32_t class_value,
1260 				  scope_index_t * scope)
1261 {
1262 	if (class_value > scope->class_perms_len) {
1263 		return 1;
1264 	}
1265 	if (ebitmap_get_bit(scope->class_perms_map + class_value - 1,
1266 			    perm_value - 1)) {
1267 		return 1;
1268 	}
1269 	return 0;
1270 }
1271 
is_perm_in_stack(uint32_t perm_value,uint32_t class_value,scope_stack_t * stack)1272 static int is_perm_in_stack(uint32_t perm_value, uint32_t class_value,
1273 			    scope_stack_t * stack)
1274 {
1275 	if (stack == NULL) {
1276 		return 0;	/* no matching scope found */
1277 	}
1278 	if (stack->type == 1) {
1279 		avrule_decl_t *decl = stack->decl;
1280 		if (is_perm_in_scope_index
1281 		    (perm_value, class_value, &decl->required)
1282 		    || is_perm_in_scope_index(perm_value, class_value,
1283 					      &decl->declared)) {
1284 			return 1;
1285 		}
1286 	} else {
1287 		/* note that conditionals can't declare or require
1288 		 * symbols, so skip this level */
1289 	}
1290 
1291 	/* not within scope of this stack, so try its parent */
1292 	return is_perm_in_stack(perm_value, class_value, stack->parent);
1293 }
1294 
is_perm_in_scope(hashtab_key_t perm_id,hashtab_key_t class_id)1295 int is_perm_in_scope(hashtab_key_t perm_id, hashtab_key_t class_id)
1296 {
1297 	class_datum_t *cladatum =
1298 	    (class_datum_t *) hashtab_search(policydbp->p_classes.table,
1299 					     class_id);
1300 	perm_datum_t *perdatum;
1301 	if (cladatum == NULL) {
1302 		return 1;
1303 	}
1304 	perdatum = (perm_datum_t *) hashtab_search(cladatum->permissions.table,
1305 						   perm_id);
1306 	if (perdatum == NULL) {
1307 		return 1;
1308 	}
1309 	return is_perm_in_stack(perdatum->s.value, cladatum->s.value,
1310 				stack_top);
1311 }
1312 
get_current_cond_list(cond_list_t * cond)1313 cond_list_t *get_current_cond_list(cond_list_t * cond)
1314 {
1315 	/* FIX ME: do something different here if in a nested
1316 	 * conditional? */
1317 	avrule_decl_t *decl = stack_top->decl;
1318 	return get_decl_cond_list(policydbp, decl, cond);
1319 }
1320 
1321 /* Append the new conditional node to the existing ones.  During
1322  * expansion the list will be reversed -- i.e., the last AV rule will
1323  * be the first one listed in the policy.  This matches the behavior
1324  * of the upstream compiler. */
append_cond_list(cond_list_t * cond)1325 void append_cond_list(cond_list_t * cond)
1326 {
1327 	cond_list_t *old_cond = get_current_cond_list(cond);
1328 	avrule_t *tmp;
1329 	assert(old_cond != NULL);	/* probably out of memory */
1330 	if (old_cond->avtrue_list == NULL) {
1331 		old_cond->avtrue_list = cond->avtrue_list;
1332 	} else {
1333 		for (tmp = old_cond->avtrue_list; tmp->next != NULL;
1334 		     tmp = tmp->next) ;
1335 		tmp->next = cond->avtrue_list;
1336 	}
1337 	if (old_cond->avfalse_list == NULL) {
1338 		old_cond->avfalse_list = cond->avfalse_list;
1339 	} else {
1340 		for (tmp = old_cond->avfalse_list; tmp->next != NULL;
1341 		     tmp = tmp->next) ;
1342 		tmp->next = cond->avfalse_list;
1343 	}
1344 
1345 	old_cond->flags |= cond->flags;
1346 }
1347 
append_avrule(avrule_t * avrule)1348 void append_avrule(avrule_t * avrule)
1349 {
1350 	avrule_decl_t *decl = stack_top->decl;
1351 
1352 	/* currently avrules follow a completely different code path
1353 	 * for handling avrules and compute types
1354 	 * (define_cond_avrule_te_avtab, define_cond_compute_type);
1355 	 * therefore there ought never be a conditional on top of the
1356 	 * scope stack */
1357 	assert(stack_top->type == 1);
1358 
1359 	if (stack_top->last_avrule == NULL) {
1360 		decl->avrules = avrule;
1361 	} else {
1362 		stack_top->last_avrule->next = avrule;
1363 	}
1364 	stack_top->last_avrule = avrule;
1365 }
1366 
1367 /* this doesn't actually append, but really prepends it */
append_role_trans(role_trans_rule_t * role_tr_rules)1368 void append_role_trans(role_trans_rule_t * role_tr_rules)
1369 {
1370 	avrule_decl_t *decl = stack_top->decl;
1371 
1372 	/* role transitions are not allowed within conditionals */
1373 	assert(stack_top->type == 1);
1374 
1375 	role_tr_rules->next = decl->role_tr_rules;
1376 	decl->role_tr_rules = role_tr_rules;
1377 }
1378 
1379 /* this doesn't actually append, but really prepends it */
append_role_allow(role_allow_rule_t * role_allow_rules)1380 void append_role_allow(role_allow_rule_t * role_allow_rules)
1381 {
1382 	avrule_decl_t *decl = stack_top->decl;
1383 
1384 	/* role allows are not allowed within conditionals */
1385 	assert(stack_top->type == 1);
1386 
1387 	role_allow_rules->next = decl->role_allow_rules;
1388 	decl->role_allow_rules = role_allow_rules;
1389 }
1390 
1391 /* this doesn't actually append, but really prepends it */
append_filename_trans(filename_trans_rule_t * filename_trans_rules)1392 void append_filename_trans(filename_trans_rule_t * filename_trans_rules)
1393 {
1394 	avrule_decl_t *decl = stack_top->decl;
1395 
1396 	/* filename transitions are not allowed within conditionals */
1397 	assert(stack_top->type == 1);
1398 
1399 	filename_trans_rules->next = decl->filename_trans_rules;
1400 	decl->filename_trans_rules = filename_trans_rules;
1401 }
1402 
1403 /* this doesn't actually append, but really prepends it */
append_range_trans(range_trans_rule_t * range_tr_rules)1404 void append_range_trans(range_trans_rule_t * range_tr_rules)
1405 {
1406 	avrule_decl_t *decl = stack_top->decl;
1407 
1408 	/* range transitions are not allowed within conditionals */
1409 	assert(stack_top->type == 1);
1410 
1411 	range_tr_rules->next = decl->range_tr_rules;
1412 	decl->range_tr_rules = range_tr_rules;
1413 }
1414 
begin_optional(int pass)1415 int begin_optional(int pass)
1416 {
1417 	avrule_block_t *block = NULL;
1418 	avrule_decl_t *decl;
1419 	if (pass == 1) {
1420 		/* allocate a new avrule block for this optional block */
1421 		if ((block = avrule_block_create()) == NULL ||
1422 		    (decl = avrule_decl_create(next_decl_id)) == NULL) {
1423 			goto cleanup;
1424 		}
1425 		block->flags |= AVRULE_OPTIONAL;
1426 		block->branch_list = decl;
1427 		last_block->next = block;
1428 	} else {
1429 		/* select the next block from the chain built during pass 1 */
1430 		block = last_block->next;
1431 		assert(block != NULL &&
1432 		       block->branch_list != NULL &&
1433 		       block->branch_list->decl_id == next_decl_id);
1434 		decl = block->branch_list;
1435 	}
1436 	if (push_stack(1, block, decl) == -1) {
1437 		goto cleanup;
1438 	}
1439 	stack_top->last_avrule = NULL;
1440 	last_block = block;
1441 	next_decl_id++;
1442 	return 0;
1443       cleanup:
1444 	yyerror("Out of memory!");
1445 	avrule_block_destroy(block);
1446 	return -1;
1447 }
1448 
end_optional(int pass)1449 int end_optional(int pass __attribute__ ((unused)))
1450 {
1451 	/* once nested conditionals are allowed, do the stack unfolding here */
1452 	pop_stack();
1453 	return 0;
1454 }
1455 
begin_optional_else(int pass)1456 int begin_optional_else(int pass)
1457 {
1458 	avrule_decl_t *decl;
1459 	assert(stack_top->type == 1 && stack_top->in_else == 0);
1460 	if (pass == 1) {
1461 		/* allocate a new declaration and add it to the
1462 		 * current chain */
1463 		if ((decl = avrule_decl_create(next_decl_id)) == NULL) {
1464 			yyerror("Out of memory!");
1465 			return -1;
1466 		}
1467 		stack_top->decl->next = decl;
1468 	} else {
1469 		/* pick the (hopefully last) declaration of this
1470 		   avrule block, built from pass 1 */
1471 		decl = stack_top->decl->next;
1472 		assert(decl != NULL &&
1473 		       decl->next == NULL && decl->decl_id == next_decl_id);
1474 	}
1475 	stack_top->in_else = 1;
1476 	stack_top->decl = decl;
1477 	stack_top->last_avrule = NULL;
1478 	stack_top->require_given = 0;
1479 	next_decl_id++;
1480 	return 0;
1481 }
1482 
copy_requirements(avrule_decl_t * dest,scope_stack_t * stack)1483 static int copy_requirements(avrule_decl_t * dest, scope_stack_t * stack)
1484 {
1485 	uint32_t i;
1486 	if (stack == NULL) {
1487 		return 0;
1488 	}
1489 	if (stack->type == 1) {
1490 		scope_index_t *src_scope = &stack->decl->required;
1491 		scope_index_t *dest_scope = &dest->required;
1492 		for (i = 0; i < SYM_NUM; i++) {
1493 			ebitmap_t *src_bitmap = &src_scope->scope[i];
1494 			ebitmap_t *dest_bitmap = &dest_scope->scope[i];
1495 			if (ebitmap_union(dest_bitmap, src_bitmap)) {
1496 				yyerror("Out of memory!");
1497 				return -1;
1498 			}
1499 		}
1500 		/* now copy class permissions */
1501 		if (src_scope->class_perms_len > dest_scope->class_perms_len) {
1502 			ebitmap_t *new_map =
1503 			    realloc(dest_scope->class_perms_map,
1504 				    src_scope->class_perms_len *
1505 				    sizeof(*new_map));
1506 			if (new_map == NULL) {
1507 				yyerror("Out of memory!");
1508 				return -1;
1509 			}
1510 			dest_scope->class_perms_map = new_map;
1511 			for (i = dest_scope->class_perms_len;
1512 			     i < src_scope->class_perms_len; i++) {
1513 				ebitmap_init(dest_scope->class_perms_map + i);
1514 			}
1515 			dest_scope->class_perms_len =
1516 			    src_scope->class_perms_len;
1517 		}
1518 		for (i = 0; i < src_scope->class_perms_len; i++) {
1519 			ebitmap_t *src_bitmap = &src_scope->class_perms_map[i];
1520 			ebitmap_t *dest_bitmap =
1521 			    &dest_scope->class_perms_map[i];
1522 			if (ebitmap_union(dest_bitmap, src_bitmap)) {
1523 				yyerror("Out of memory!");
1524 				return -1;
1525 			}
1526 		}
1527 	}
1528 	return copy_requirements(dest, stack->parent);
1529 }
1530 
1531 /* During pass 1, check that at least one thing was required within
1532  * this block, for those places where a REQUIRED is necessary.  During
1533  * pass 2, have this block inherit its parents' requirements.  Return
1534  * 0 on success, -1 on failure. */
end_avrule_block(int pass)1535 int end_avrule_block(int pass)
1536 {
1537 	avrule_decl_t *decl = stack_top->decl;
1538 	assert(stack_top->type == 1);
1539 	if (pass == 2) {
1540 		/* this avrule_decl inherits all of its parents'
1541 		 * requirements */
1542 		if (copy_requirements(decl, stack_top->parent) == -1) {
1543 			return -1;
1544 		}
1545 		return 0;
1546 	}
1547 	if (!stack_top->in_else && !stack_top->require_given) {
1548 		if (policydbp->policy_type == POLICY_BASE
1549 		    && stack_top->parent != NULL) {
1550 			/* if this is base no require should be in the global block */
1551 			return 0;
1552 		} else {
1553 			/* non-ELSE branches must have at least one thing required */
1554 			yyerror("This block has no require section.");
1555 			return -1;
1556 		}
1557 	}
1558 	return 0;
1559 }
1560 
1561 /* Push a new scope on to the stack and update the 'last' pointer.
1562  * Return 0 on success, -1 if out * of memory. */
push_stack(int stack_type,...)1563 static int push_stack(int stack_type, ...)
1564 {
1565 	scope_stack_t *s = calloc(1, sizeof(*s));
1566 	va_list ap;
1567 	if (s == NULL) {
1568 		return -1;
1569 	}
1570 	va_start(ap, stack_type);
1571 	switch (s->type = stack_type) {
1572 	case 1:{
1573 			s->u.avrule = va_arg(ap, avrule_block_t *);
1574 			s->decl = va_arg(ap, avrule_decl_t *);
1575 			break;
1576 		}
1577 	case 2:{
1578 			s->u.cond_list = va_arg(ap, cond_list_t *);
1579 			break;
1580 		}
1581 	default:
1582 		/* invalid stack type given */
1583 		assert(0);
1584 	}
1585 	va_end(ap);
1586 	s->parent = stack_top;
1587 	s->child = NULL;
1588 	stack_top = s;
1589 	return 0;
1590 }
1591 
1592 /* Pop off the most recently added from the stack.  Update the 'last'
1593  * pointer. */
pop_stack(void)1594 static void pop_stack(void)
1595 {
1596 	scope_stack_t *parent;
1597 	assert(stack_top != NULL);
1598 	parent = stack_top->parent;
1599 	if (parent != NULL) {
1600 		parent->child = NULL;
1601 	}
1602 	free(stack_top);
1603 	stack_top = parent;
1604 }
1605