• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 #include <stdlib.h>
2 #include <stddef.h>
3 #include <string.h>
4 
5 #include "private.h"
6 #include "debug.h"
7 #include "handle.h"
8 
9 #include <sepol/policydb/policydb.h>
10 #include <sepol/policydb/hashtab.h>
11 #include <sepol/policydb/expand.h>
12 #include "user_internal.h"
13 #include "mls.h"
14 
user_to_record(sepol_handle_t * handle,const policydb_t * policydb,int user_idx,sepol_user_t ** record)15 static int user_to_record(sepol_handle_t * handle,
16 			  const policydb_t * policydb,
17 			  int user_idx, sepol_user_t ** record)
18 {
19 
20 	const char *name = policydb->p_user_val_to_name[user_idx];
21 	user_datum_t *usrdatum = policydb->user_val_to_struct[user_idx];
22 	ebitmap_t *roles;
23 	ebitmap_node_t *rnode;
24 	unsigned bit;
25 
26 	sepol_user_t *tmp_record = NULL;
27 
28 	if (!usrdatum)
29 		goto err;
30 
31 	roles = &(usrdatum->roles.roles);
32 
33 	if (sepol_user_create(handle, &tmp_record) < 0)
34 		goto err;
35 
36 	if (sepol_user_set_name(handle, tmp_record, name) < 0)
37 		goto err;
38 
39 	/* Extract roles */
40 	ebitmap_for_each_bit(roles, rnode, bit) {
41 		if (ebitmap_node_get_bit(rnode, bit)) {
42 			char *role = policydb->p_role_val_to_name[bit];
43 			if (sepol_user_add_role(handle, tmp_record, role) < 0)
44 				goto err;
45 		}
46 	}
47 
48 	/* Extract MLS info */
49 	if (policydb->mls) {
50 		context_struct_t context;
51 		char *str;
52 
53 		context_init(&context);
54 		if (mls_level_cpy(&context.range.level[0],
55 				  &usrdatum->exp_dfltlevel) < 0) {
56 			ERR(handle, "could not copy MLS level");
57 			context_destroy(&context);
58 			goto err;
59 		}
60 		if (mls_level_cpy(&context.range.level[1],
61 				  &usrdatum->exp_dfltlevel) < 0) {
62 			ERR(handle, "could not copy MLS level");
63 			context_destroy(&context);
64 			goto err;
65 		}
66 		if (mls_to_string(handle, policydb, &context, &str) < 0) {
67 			context_destroy(&context);
68 			goto err;
69 		}
70 		context_destroy(&context);
71 
72 		if (sepol_user_set_mlslevel(handle, tmp_record, str) < 0) {
73 			free(str);
74 			goto err;
75 		}
76 		free(str);
77 
78 		context_init(&context);
79 		if (mls_range_cpy(&context.range, &usrdatum->exp_range) < 0) {
80 			ERR(handle, "could not copy MLS range");
81 			context_destroy(&context);
82 			goto err;
83 		}
84 		if (mls_to_string(handle, policydb, &context, &str) < 0) {
85 			context_destroy(&context);
86 			goto err;
87 		}
88 		context_destroy(&context);
89 
90 		if (sepol_user_set_mlsrange(handle, tmp_record, str) < 0) {
91 			free(str);
92 			goto err;
93 		}
94 		free(str);
95 	}
96 
97 	*record = tmp_record;
98 	return STATUS_SUCCESS;
99 
100       err:
101 	/* FIXME: handle error */
102 	sepol_user_free(tmp_record);
103 	return STATUS_ERR;
104 }
105 
sepol_user_modify(sepol_handle_t * handle,sepol_policydb_t * p,const sepol_user_key_t * key,const sepol_user_t * user)106 int sepol_user_modify(sepol_handle_t * handle,
107 		      sepol_policydb_t * p,
108 		      const sepol_user_key_t * key, const sepol_user_t * user)
109 {
110 
111 	policydb_t *policydb = &p->p;
112 
113 	/* For user data */
114 	const char *cname, *cmls_level, *cmls_range;
115 	char *name = NULL;
116 
117 	const char **roles = NULL;
118 	unsigned int num_roles = 0;
119 
120 	/* Low-level representation */
121 	user_datum_t *usrdatum = NULL;
122 	role_datum_t *roldatum;
123 	unsigned int i;
124 
125 	context_struct_t context;
126 	unsigned bit;
127 	int new = 0;
128 
129 	ebitmap_node_t *rnode;
130 
131 	/* First, extract all the data */
132 	sepol_user_key_unpack(key, &cname);
133 
134 	cmls_level = sepol_user_get_mlslevel(user);
135 	cmls_range = sepol_user_get_mlsrange(user);
136 
137 	/* Make sure that worked properly */
138 	if (sepol_user_get_roles(handle, user, &roles, &num_roles) < 0)
139 		goto err;
140 
141 	/* Now, see if a user exists */
142 	usrdatum = hashtab_search(policydb->p_users.table, cname);
143 
144 	/* If it does, we will modify it */
145 	if (usrdatum) {
146 
147 		int value_cp = usrdatum->s.value;
148 		user_datum_destroy(usrdatum);
149 		user_datum_init(usrdatum);
150 		usrdatum->s.value = value_cp;
151 
152 		/* Otherwise, create a new one */
153 	} else {
154 		usrdatum = (user_datum_t *) malloc(sizeof(user_datum_t));
155 		if (!usrdatum)
156 			goto omem;
157 		user_datum_init(usrdatum);
158 		new = 1;
159 	}
160 
161 	/* For every role */
162 	for (i = 0; i < num_roles; i++) {
163 
164 		/* Search for the role */
165 		roldatum = hashtab_search(policydb->p_roles.table, roles[i]);
166 		if (!roldatum) {
167 			ERR(handle, "undefined role %s for user %s",
168 			    roles[i], cname);
169 			goto err;
170 		}
171 
172 		/* Set the role and every role it dominates */
173 		ebitmap_for_each_bit(&roldatum->dominates, rnode, bit) {
174 			if (ebitmap_node_get_bit(rnode, bit)) {
175 				if (ebitmap_set_bit
176 				    (&(usrdatum->roles.roles), bit, 1))
177 					goto omem;
178 			}
179 		}
180 	}
181 
182 	/* For MLS systems */
183 	if (policydb->mls) {
184 
185 		/* MLS level */
186 		if (cmls_level == NULL) {
187 			ERR(handle, "MLS is enabled, but no MLS "
188 			    "default level was defined for user %s", cname);
189 			goto err;
190 		}
191 
192 		context_init(&context);
193 		if (mls_from_string(handle, policydb, cmls_level, &context) < 0) {
194 			context_destroy(&context);
195 			goto err;
196 		}
197 		if (mls_level_cpy(&usrdatum->exp_dfltlevel,
198 				  &context.range.level[0]) < 0) {
199 			ERR(handle, "could not copy MLS level %s", cmls_level);
200 			context_destroy(&context);
201 			goto err;
202 		}
203 		context_destroy(&context);
204 
205 		/* MLS range */
206 		if (cmls_range == NULL) {
207 			ERR(handle, "MLS is enabled, but no MLS"
208 			    "range was defined for user %s", cname);
209 			goto err;
210 		}
211 
212 		context_init(&context);
213 		if (mls_from_string(handle, policydb, cmls_range, &context) < 0) {
214 			context_destroy(&context);
215 			goto err;
216 		}
217 		if (mls_range_cpy(&usrdatum->exp_range, &context.range) < 0) {
218 			ERR(handle, "could not copy MLS range %s", cmls_range);
219 			context_destroy(&context);
220 			goto err;
221 		}
222 		context_destroy(&context);
223 	} else if (cmls_level != NULL || cmls_range != NULL) {
224 		ERR(handle, "MLS is disabled, but MLS level/range "
225 		    "was found for user %s", cname);
226 		goto err;
227 	}
228 
229 	/* If there are no errors, and this is a new user, add the user to policy */
230 	if (new) {
231 		void *tmp_ptr;
232 
233 		/* Ensure reverse lookup array has enough space */
234 		tmp_ptr = realloc(policydb->user_val_to_struct,
235 				  (policydb->p_users.nprim +
236 				   1) * sizeof(user_datum_t *));
237 		if (!tmp_ptr)
238 			goto omem;
239 		policydb->user_val_to_struct = tmp_ptr;
240 		policydb->user_val_to_struct[policydb->p_users.nprim] = NULL;
241 
242 		tmp_ptr = realloc(policydb->sym_val_to_name[SYM_USERS],
243 				  (policydb->p_users.nprim +
244 				   1) * sizeof(char *));
245 		if (!tmp_ptr)
246 			goto omem;
247 		policydb->sym_val_to_name[SYM_USERS] = tmp_ptr;
248 		policydb->p_user_val_to_name[policydb->p_users.nprim] = NULL;
249 
250 		/* Need to copy the user name */
251 		name = strdup(cname);
252 		if (!name)
253 			goto omem;
254 
255 		/* Store user */
256 		usrdatum->s.value = ++policydb->p_users.nprim;
257 		if (hashtab_insert(policydb->p_users.table, name,
258 				   (hashtab_datum_t) usrdatum) < 0)
259 			goto omem;
260 
261 		/* Set up reverse entry */
262 		policydb->p_user_val_to_name[usrdatum->s.value - 1] = name;
263 		policydb->user_val_to_struct[usrdatum->s.value - 1] = usrdatum;
264 		name = NULL;
265 
266 		/* Expand roles */
267 		if (role_set_expand(&usrdatum->roles, &usrdatum->cache,
268 				    policydb, NULL, NULL)) {
269 			ERR(handle, "unable to expand role set");
270 			goto err;
271 		}
272 	}
273 
274 	free(roles);
275 	return STATUS_SUCCESS;
276 
277       omem:
278 	ERR(handle, "out of memory");
279 
280       err:
281 	ERR(handle, "could not load %s into policy", name);
282 
283 	free(name);
284 	free(roles);
285 	if (new && usrdatum) {
286 		role_set_destroy(&usrdatum->roles);
287 		free(usrdatum);
288 	}
289 	return STATUS_ERR;
290 }
291 
sepol_user_exists(sepol_handle_t * handle,const sepol_policydb_t * p,const sepol_user_key_t * key,int * response)292 int sepol_user_exists(sepol_handle_t * handle __attribute__ ((unused)),
293 		      const sepol_policydb_t * p,
294 		      const sepol_user_key_t * key, int *response)
295 {
296 
297 	const policydb_t *policydb = &p->p;
298 
299 	const char *cname;
300 	sepol_user_key_unpack(key, &cname);
301 
302 	*response = (hashtab_search(policydb->p_users.table, cname) != NULL);
303 
304 	return STATUS_SUCCESS;
305 }
306 
sepol_user_count(sepol_handle_t * handle,const sepol_policydb_t * p,unsigned int * response)307 int sepol_user_count(sepol_handle_t * handle __attribute__ ((unused)),
308 		     const sepol_policydb_t * p, unsigned int *response)
309 {
310 
311 	const policydb_t *policydb = &p->p;
312 	*response = policydb->p_users.nprim;
313 
314 	return STATUS_SUCCESS;
315 }
316 
sepol_user_query(sepol_handle_t * handle,const sepol_policydb_t * p,const sepol_user_key_t * key,sepol_user_t ** response)317 int sepol_user_query(sepol_handle_t * handle,
318 		     const sepol_policydb_t * p,
319 		     const sepol_user_key_t * key, sepol_user_t ** response)
320 {
321 
322 	const policydb_t *policydb = &p->p;
323 	user_datum_t *usrdatum = NULL;
324 
325 	const char *cname;
326 	sepol_user_key_unpack(key, &cname);
327 
328 	usrdatum = hashtab_search(policydb->p_users.table, cname);
329 
330 	if (!usrdatum) {
331 		*response = NULL;
332 		return STATUS_SUCCESS;
333 	}
334 
335 	if (user_to_record(handle, policydb, usrdatum->s.value - 1, response) <
336 	    0)
337 		goto err;
338 
339 	return STATUS_SUCCESS;
340 
341       err:
342 	ERR(handle, "could not query user %s", cname);
343 	return STATUS_ERR;
344 }
345 
sepol_user_iterate(sepol_handle_t * handle,const sepol_policydb_t * p,int (* fn)(const sepol_user_t * user,void * fn_arg),void * arg)346 int sepol_user_iterate(sepol_handle_t * handle,
347 		       const sepol_policydb_t * p,
348 		       int (*fn) (const sepol_user_t * user,
349 				  void *fn_arg), void *arg)
350 {
351 
352 	const policydb_t *policydb = &p->p;
353 	unsigned int nusers = policydb->p_users.nprim;
354 	sepol_user_t *user = NULL;
355 	unsigned int i;
356 
357 	/* For each user */
358 	for (i = 0; i < nusers; i++) {
359 
360 		int status;
361 
362 		if (user_to_record(handle, policydb, i, &user) < 0)
363 			goto err;
364 
365 		/* Invoke handler */
366 		status = fn(user, arg);
367 		if (status < 0)
368 			goto err;
369 
370 		sepol_user_free(user);
371 		user = NULL;
372 
373 		/* Handler requested exit */
374 		if (status > 0)
375 			break;
376 	}
377 
378 	return STATUS_SUCCESS;
379 
380       err:
381 	ERR(handle, "could not iterate over users");
382 	sepol_user_free(user);
383 	return STATUS_ERR;
384 }
385