Thomas Gleixner | a10e763 | 2019-05-31 01:09:32 -0700 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0-only |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2 | /* Authors: Karl MacMillan <kmacmillan@tresys.com> |
Eric Paris | 7c2b240 | 2008-04-18 17:38:29 -0400 | [diff] [blame] | 3 | * Frank Mayer <mayerf@tresys.com> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4 | * |
| 5 | * Copyright (C) 2003 - 2004 Tresys Technology, LLC |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 6 | */ |
| 7 | |
| 8 | #include <linux/kernel.h> |
| 9 | #include <linux/errno.h> |
| 10 | #include <linux/string.h> |
| 11 | #include <linux/spinlock.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 12 | #include <linux/slab.h> |
| 13 | |
| 14 | #include "security.h" |
| 15 | #include "conditional.h" |
Jeff Vander Stoep | fa1aa14 | 2015-07-10 17:19:56 -0400 | [diff] [blame] | 16 | #include "services.h" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 17 | |
| 18 | /* |
| 19 | * cond_evaluate_expr evaluates a conditional expr |
| 20 | * in reverse polish notation. It returns true (1), false (0), |
| 21 | * or undefined (-1). Undefined occurs when the expression |
| 22 | * exceeds the stack depth of COND_EXPR_MAXDEPTH. |
| 23 | */ |
| 24 | static int cond_evaluate_expr(struct policydb *p, struct cond_expr *expr) |
| 25 | { |
| 26 | |
| 27 | struct cond_expr *cur; |
| 28 | int s[COND_EXPR_MAXDEPTH]; |
| 29 | int sp = -1; |
| 30 | |
Vesa-Matti Kari | dbc74c6 | 2008-08-07 03:18:20 +0300 | [diff] [blame] | 31 | for (cur = expr; cur; cur = cur->next) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 32 | switch (cur->expr_type) { |
| 33 | case COND_BOOL: |
| 34 | if (sp == (COND_EXPR_MAXDEPTH - 1)) |
| 35 | return -1; |
| 36 | sp++; |
| 37 | s[sp] = p->bool_val_to_struct[cur->bool - 1]->state; |
| 38 | break; |
| 39 | case COND_NOT: |
| 40 | if (sp < 0) |
| 41 | return -1; |
| 42 | s[sp] = !s[sp]; |
| 43 | break; |
| 44 | case COND_OR: |
| 45 | if (sp < 1) |
| 46 | return -1; |
| 47 | sp--; |
| 48 | s[sp] |= s[sp + 1]; |
| 49 | break; |
| 50 | case COND_AND: |
| 51 | if (sp < 1) |
| 52 | return -1; |
| 53 | sp--; |
| 54 | s[sp] &= s[sp + 1]; |
| 55 | break; |
| 56 | case COND_XOR: |
| 57 | if (sp < 1) |
| 58 | return -1; |
| 59 | sp--; |
| 60 | s[sp] ^= s[sp + 1]; |
| 61 | break; |
| 62 | case COND_EQ: |
| 63 | if (sp < 1) |
| 64 | return -1; |
| 65 | sp--; |
| 66 | s[sp] = (s[sp] == s[sp + 1]); |
| 67 | break; |
| 68 | case COND_NEQ: |
| 69 | if (sp < 1) |
| 70 | return -1; |
| 71 | sp--; |
| 72 | s[sp] = (s[sp] != s[sp + 1]); |
| 73 | break; |
| 74 | default: |
| 75 | return -1; |
| 76 | } |
| 77 | } |
| 78 | return s[0]; |
| 79 | } |
| 80 | |
| 81 | /* |
| 82 | * evaluate_cond_node evaluates the conditional stored in |
| 83 | * a struct cond_node and if the result is different than the |
| 84 | * current state of the node it sets the rules in the true/false |
| 85 | * list appropriately. If the result of the expression is undefined |
| 86 | * all of the rules are disabled for safety. |
| 87 | */ |
| 88 | int evaluate_cond_node(struct policydb *p, struct cond_node *node) |
| 89 | { |
| 90 | int new_state; |
Eric Paris | 7c2b240 | 2008-04-18 17:38:29 -0400 | [diff] [blame] | 91 | struct cond_av_list *cur; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 92 | |
| 93 | new_state = cond_evaluate_expr(p, node->expr); |
| 94 | if (new_state != node->cur_state) { |
| 95 | node->cur_state = new_state; |
| 96 | if (new_state == -1) |
peter enderborg | ab48576 | 2018-06-12 10:09:00 +0200 | [diff] [blame] | 97 | pr_err("SELinux: expression result was undefined - disabling all rules.\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 98 | /* turn the rules on or off */ |
Vesa-Matti Kari | dbc74c6 | 2008-08-07 03:18:20 +0300 | [diff] [blame] | 99 | for (cur = node->true_list; cur; cur = cur->next) { |
Eric Paris | 7c2b240 | 2008-04-18 17:38:29 -0400 | [diff] [blame] | 100 | if (new_state <= 0) |
Stephen Smalley | 782ebb9 | 2005-09-03 15:55:16 -0700 | [diff] [blame] | 101 | cur->node->key.specified &= ~AVTAB_ENABLED; |
Eric Paris | 7c2b240 | 2008-04-18 17:38:29 -0400 | [diff] [blame] | 102 | else |
Stephen Smalley | 782ebb9 | 2005-09-03 15:55:16 -0700 | [diff] [blame] | 103 | cur->node->key.specified |= AVTAB_ENABLED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 104 | } |
| 105 | |
Vesa-Matti Kari | dbc74c6 | 2008-08-07 03:18:20 +0300 | [diff] [blame] | 106 | for (cur = node->false_list; cur; cur = cur->next) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | /* -1 or 1 */ |
Eric Paris | 7c2b240 | 2008-04-18 17:38:29 -0400 | [diff] [blame] | 108 | if (new_state) |
Stephen Smalley | 782ebb9 | 2005-09-03 15:55:16 -0700 | [diff] [blame] | 109 | cur->node->key.specified &= ~AVTAB_ENABLED; |
Eric Paris | 7c2b240 | 2008-04-18 17:38:29 -0400 | [diff] [blame] | 110 | else |
Stephen Smalley | 782ebb9 | 2005-09-03 15:55:16 -0700 | [diff] [blame] | 111 | cur->node->key.specified |= AVTAB_ENABLED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 112 | } |
| 113 | } |
| 114 | return 0; |
| 115 | } |
| 116 | |
| 117 | int cond_policydb_init(struct policydb *p) |
| 118 | { |
Dan Carpenter | 38184c5 | 2010-06-12 20:55:01 +0200 | [diff] [blame] | 119 | int rc; |
| 120 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 121 | p->bool_val_to_struct = NULL; |
| 122 | p->cond_list = NULL; |
Dan Carpenter | 38184c5 | 2010-06-12 20:55:01 +0200 | [diff] [blame] | 123 | |
| 124 | rc = avtab_init(&p->te_cond_avtab); |
| 125 | if (rc) |
| 126 | return rc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 127 | |
| 128 | return 0; |
| 129 | } |
| 130 | |
| 131 | static void cond_av_list_destroy(struct cond_av_list *list) |
| 132 | { |
| 133 | struct cond_av_list *cur, *next; |
Vesa-Matti Kari | dbc74c6 | 2008-08-07 03:18:20 +0300 | [diff] [blame] | 134 | for (cur = list; cur; cur = next) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 135 | next = cur->next; |
| 136 | /* the avtab_ptr_t node is destroy by the avtab */ |
| 137 | kfree(cur); |
| 138 | } |
| 139 | } |
| 140 | |
| 141 | static void cond_node_destroy(struct cond_node *node) |
| 142 | { |
| 143 | struct cond_expr *cur_expr, *next_expr; |
| 144 | |
Vesa-Matti Kari | dbc74c6 | 2008-08-07 03:18:20 +0300 | [diff] [blame] | 145 | for (cur_expr = node->expr; cur_expr; cur_expr = next_expr) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 146 | next_expr = cur_expr->next; |
| 147 | kfree(cur_expr); |
| 148 | } |
| 149 | cond_av_list_destroy(node->true_list); |
| 150 | cond_av_list_destroy(node->false_list); |
| 151 | kfree(node); |
| 152 | } |
| 153 | |
| 154 | static void cond_list_destroy(struct cond_node *list) |
| 155 | { |
| 156 | struct cond_node *next, *cur; |
| 157 | |
| 158 | if (list == NULL) |
| 159 | return; |
| 160 | |
Vesa-Matti Kari | dbc74c6 | 2008-08-07 03:18:20 +0300 | [diff] [blame] | 161 | for (cur = list; cur; cur = next) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 162 | next = cur->next; |
| 163 | cond_node_destroy(cur); |
| 164 | } |
| 165 | } |
| 166 | |
| 167 | void cond_policydb_destroy(struct policydb *p) |
| 168 | { |
Jesper Juhl | 9a5f04b | 2005-06-25 14:58:51 -0700 | [diff] [blame] | 169 | kfree(p->bool_val_to_struct); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 170 | avtab_destroy(&p->te_cond_avtab); |
| 171 | cond_list_destroy(p->cond_list); |
| 172 | } |
| 173 | |
| 174 | int cond_init_bool_indexes(struct policydb *p) |
| 175 | { |
Jesper Juhl | 9a5f04b | 2005-06-25 14:58:51 -0700 | [diff] [blame] | 176 | kfree(p->bool_val_to_struct); |
Markus Elfring | f6076f7 | 2017-01-14 10:48:28 +0100 | [diff] [blame] | 177 | p->bool_val_to_struct = kmalloc_array(p->p_bools.nprim, |
| 178 | sizeof(*p->bool_val_to_struct), |
| 179 | GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 180 | if (!p->bool_val_to_struct) |
Davidlohr Bueso | 3ac285ff | 2011-01-21 12:28:04 -0300 | [diff] [blame] | 181 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 182 | return 0; |
| 183 | } |
| 184 | |
| 185 | int cond_destroy_bool(void *key, void *datum, void *p) |
| 186 | { |
Jesper Juhl | 9a5f04b | 2005-06-25 14:58:51 -0700 | [diff] [blame] | 187 | kfree(key); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 188 | kfree(datum); |
| 189 | return 0; |
| 190 | } |
| 191 | |
| 192 | int cond_index_bool(void *key, void *datum, void *datap) |
| 193 | { |
| 194 | struct policydb *p; |
| 195 | struct cond_bool_datum *booldatum; |
| 196 | |
| 197 | booldatum = datum; |
| 198 | p = datap; |
| 199 | |
| 200 | if (!booldatum->value || booldatum->value > p->p_bools.nprim) |
| 201 | return -EINVAL; |
| 202 | |
Kent Overstreet | acdf52d | 2019-03-11 23:31:10 -0700 | [diff] [blame] | 203 | p->sym_val_to_name[SYM_BOOLS][booldatum->value - 1] = key; |
Eric Paris | 7c2b240 | 2008-04-18 17:38:29 -0400 | [diff] [blame] | 204 | p->bool_val_to_struct[booldatum->value - 1] = booldatum; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 205 | |
| 206 | return 0; |
| 207 | } |
| 208 | |
| 209 | static int bool_isvalid(struct cond_bool_datum *b) |
| 210 | { |
| 211 | if (!(b->state == 0 || b->state == 1)) |
| 212 | return 0; |
| 213 | return 1; |
| 214 | } |
| 215 | |
| 216 | int cond_read_bool(struct policydb *p, struct hashtab *h, void *fp) |
| 217 | { |
| 218 | char *key = NULL; |
| 219 | struct cond_bool_datum *booldatum; |
Alexey Dobriyan | b5bf6c5 | 2005-09-03 15:55:17 -0700 | [diff] [blame] | 220 | __le32 buf[3]; |
| 221 | u32 len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 222 | int rc; |
| 223 | |
Markus Elfring | fb13a31 | 2017-01-14 11:22:12 +0100 | [diff] [blame] | 224 | booldatum = kzalloc(sizeof(*booldatum), GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 225 | if (!booldatum) |
Dan Carpenter | 338437f | 2010-06-12 20:56:01 +0200 | [diff] [blame] | 226 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 227 | |
| 228 | rc = next_entry(buf, fp, sizeof buf); |
Dan Carpenter | 338437f | 2010-06-12 20:56:01 +0200 | [diff] [blame] | 229 | if (rc) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 230 | goto err; |
| 231 | |
| 232 | booldatum->value = le32_to_cpu(buf[0]); |
| 233 | booldatum->state = le32_to_cpu(buf[1]); |
| 234 | |
Dan Carpenter | 338437f | 2010-06-12 20:56:01 +0200 | [diff] [blame] | 235 | rc = -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 236 | if (!bool_isvalid(booldatum)) |
| 237 | goto err; |
| 238 | |
| 239 | len = le32_to_cpu(buf[2]); |
William Roberts | 7c686af | 2016-08-30 09:28:11 -0700 | [diff] [blame] | 240 | if (((len == 0) || (len == (u32)-1))) |
| 241 | goto err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 242 | |
Dan Carpenter | 338437f | 2010-06-12 20:56:01 +0200 | [diff] [blame] | 243 | rc = -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 244 | key = kmalloc(len + 1, GFP_KERNEL); |
| 245 | if (!key) |
| 246 | goto err; |
| 247 | rc = next_entry(key, fp, len); |
Dan Carpenter | 338437f | 2010-06-12 20:56:01 +0200 | [diff] [blame] | 248 | if (rc) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 249 | goto err; |
Vesa-Matti J Kari | df4ea865 | 2008-07-20 23:57:01 +0300 | [diff] [blame] | 250 | key[len] = '\0'; |
Dan Carpenter | 338437f | 2010-06-12 20:56:01 +0200 | [diff] [blame] | 251 | rc = hashtab_insert(h, key, booldatum); |
| 252 | if (rc) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 253 | goto err; |
| 254 | |
| 255 | return 0; |
| 256 | err: |
| 257 | cond_destroy_bool(key, booldatum, NULL); |
Dan Carpenter | 338437f | 2010-06-12 20:56:01 +0200 | [diff] [blame] | 258 | return rc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 259 | } |
| 260 | |
Eric Paris | 7c2b240 | 2008-04-18 17:38:29 -0400 | [diff] [blame] | 261 | struct cond_insertf_data { |
Stephen Smalley | 782ebb9 | 2005-09-03 15:55:16 -0700 | [diff] [blame] | 262 | struct policydb *p; |
| 263 | struct cond_av_list *other; |
| 264 | struct cond_av_list *head; |
| 265 | struct cond_av_list *tail; |
| 266 | }; |
| 267 | |
| 268 | static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum *d, void *ptr) |
| 269 | { |
| 270 | struct cond_insertf_data *data = ptr; |
| 271 | struct policydb *p = data->p; |
| 272 | struct cond_av_list *other = data->other, *list, *cur; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 273 | struct avtab_node *node_ptr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 274 | u8 found; |
Dan Carpenter | 9d623b1 | 2010-06-12 20:52:19 +0200 | [diff] [blame] | 275 | int rc = -EINVAL; |
Stephen Smalley | 782ebb9 | 2005-09-03 15:55:16 -0700 | [diff] [blame] | 276 | |
| 277 | /* |
| 278 | * For type rules we have to make certain there aren't any |
| 279 | * conflicting rules by searching the te_avtab and the |
| 280 | * cond_te_avtab. |
| 281 | */ |
| 282 | if (k->specified & AVTAB_TYPE) { |
| 283 | if (avtab_search(&p->te_avtab, k)) { |
peter enderborg | ab48576 | 2018-06-12 10:09:00 +0200 | [diff] [blame] | 284 | pr_err("SELinux: type rule already exists outside of a conditional.\n"); |
Stephen Smalley | 782ebb9 | 2005-09-03 15:55:16 -0700 | [diff] [blame] | 285 | goto err; |
| 286 | } |
| 287 | /* |
| 288 | * If we are reading the false list other will be a pointer to |
| 289 | * the true list. We can have duplicate entries if there is only |
| 290 | * 1 other entry and it is in our true list. |
| 291 | * |
| 292 | * If we are reading the true list (other == NULL) there shouldn't |
| 293 | * be any other entries. |
| 294 | */ |
| 295 | if (other) { |
| 296 | node_ptr = avtab_search_node(&p->te_cond_avtab, k); |
| 297 | if (node_ptr) { |
| 298 | if (avtab_search_node_next(node_ptr, k->specified)) { |
peter enderborg | ab48576 | 2018-06-12 10:09:00 +0200 | [diff] [blame] | 299 | pr_err("SELinux: too many conflicting type rules.\n"); |
Stephen Smalley | 782ebb9 | 2005-09-03 15:55:16 -0700 | [diff] [blame] | 300 | goto err; |
| 301 | } |
| 302 | found = 0; |
Vesa-Matti Kari | dbc74c6 | 2008-08-07 03:18:20 +0300 | [diff] [blame] | 303 | for (cur = other; cur; cur = cur->next) { |
Stephen Smalley | 782ebb9 | 2005-09-03 15:55:16 -0700 | [diff] [blame] | 304 | if (cur->node == node_ptr) { |
| 305 | found = 1; |
| 306 | break; |
| 307 | } |
| 308 | } |
| 309 | if (!found) { |
peter enderborg | ab48576 | 2018-06-12 10:09:00 +0200 | [diff] [blame] | 310 | pr_err("SELinux: conflicting type rules.\n"); |
Stephen Smalley | 782ebb9 | 2005-09-03 15:55:16 -0700 | [diff] [blame] | 311 | goto err; |
| 312 | } |
| 313 | } |
| 314 | } else { |
| 315 | if (avtab_search(&p->te_cond_avtab, k)) { |
peter enderborg | ab48576 | 2018-06-12 10:09:00 +0200 | [diff] [blame] | 316 | pr_err("SELinux: conflicting type rules when adding type rule for true.\n"); |
Stephen Smalley | 782ebb9 | 2005-09-03 15:55:16 -0700 | [diff] [blame] | 317 | goto err; |
| 318 | } |
| 319 | } |
| 320 | } |
| 321 | |
| 322 | node_ptr = avtab_insert_nonunique(&p->te_cond_avtab, k, d); |
| 323 | if (!node_ptr) { |
peter enderborg | ab48576 | 2018-06-12 10:09:00 +0200 | [diff] [blame] | 324 | pr_err("SELinux: could not insert rule.\n"); |
Dan Carpenter | 9d623b1 | 2010-06-12 20:52:19 +0200 | [diff] [blame] | 325 | rc = -ENOMEM; |
Stephen Smalley | 782ebb9 | 2005-09-03 15:55:16 -0700 | [diff] [blame] | 326 | goto err; |
| 327 | } |
| 328 | |
Markus Elfring | fb13a31 | 2017-01-14 11:22:12 +0100 | [diff] [blame] | 329 | list = kzalloc(sizeof(*list), GFP_KERNEL); |
Dan Carpenter | 9d623b1 | 2010-06-12 20:52:19 +0200 | [diff] [blame] | 330 | if (!list) { |
| 331 | rc = -ENOMEM; |
Stephen Smalley | 782ebb9 | 2005-09-03 15:55:16 -0700 | [diff] [blame] | 332 | goto err; |
Dan Carpenter | 9d623b1 | 2010-06-12 20:52:19 +0200 | [diff] [blame] | 333 | } |
Stephen Smalley | 782ebb9 | 2005-09-03 15:55:16 -0700 | [diff] [blame] | 334 | |
| 335 | list->node = node_ptr; |
| 336 | if (!data->head) |
| 337 | data->head = list; |
| 338 | else |
| 339 | data->tail->next = list; |
| 340 | data->tail = list; |
| 341 | return 0; |
| 342 | |
| 343 | err: |
| 344 | cond_av_list_destroy(data->head); |
| 345 | data->head = NULL; |
Dan Carpenter | 9d623b1 | 2010-06-12 20:52:19 +0200 | [diff] [blame] | 346 | return rc; |
Stephen Smalley | 782ebb9 | 2005-09-03 15:55:16 -0700 | [diff] [blame] | 347 | } |
| 348 | |
| 349 | static int cond_read_av_list(struct policydb *p, void *fp, struct cond_av_list **ret_list, struct cond_av_list *other) |
| 350 | { |
| 351 | int i, rc; |
Alexey Dobriyan | b5bf6c5 | 2005-09-03 15:55:17 -0700 | [diff] [blame] | 352 | __le32 buf[1]; |
| 353 | u32 len; |
Stephen Smalley | 782ebb9 | 2005-09-03 15:55:16 -0700 | [diff] [blame] | 354 | struct cond_insertf_data data; |
| 355 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 356 | *ret_list = NULL; |
| 357 | |
Stephen Smalley | 782ebb9 | 2005-09-03 15:55:16 -0700 | [diff] [blame] | 358 | rc = next_entry(buf, fp, sizeof(u32)); |
Dan Carpenter | 9d623b1 | 2010-06-12 20:52:19 +0200 | [diff] [blame] | 359 | if (rc) |
| 360 | return rc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 361 | |
| 362 | len = le32_to_cpu(buf[0]); |
Eric Paris | 7c2b240 | 2008-04-18 17:38:29 -0400 | [diff] [blame] | 363 | if (len == 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 364 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 365 | |
Stephen Smalley | 782ebb9 | 2005-09-03 15:55:16 -0700 | [diff] [blame] | 366 | data.p = p; |
| 367 | data.other = other; |
| 368 | data.head = NULL; |
| 369 | data.tail = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 370 | for (i = 0; i < len; i++) { |
Stephen Smalley | 45e5421 | 2007-11-07 10:08:00 -0500 | [diff] [blame] | 371 | rc = avtab_read_item(&p->te_cond_avtab, fp, p, cond_insertf, |
| 372 | &data); |
Stephen Smalley | 782ebb9 | 2005-09-03 15:55:16 -0700 | [diff] [blame] | 373 | if (rc) |
| 374 | return rc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 375 | } |
| 376 | |
Stephen Smalley | 782ebb9 | 2005-09-03 15:55:16 -0700 | [diff] [blame] | 377 | *ret_list = data.head; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 378 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 379 | } |
| 380 | |
| 381 | static int expr_isvalid(struct policydb *p, struct cond_expr *expr) |
| 382 | { |
| 383 | if (expr->expr_type <= 0 || expr->expr_type > COND_LAST) { |
peter enderborg | ab48576 | 2018-06-12 10:09:00 +0200 | [diff] [blame] | 384 | pr_err("SELinux: conditional expressions uses unknown operator.\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 385 | return 0; |
| 386 | } |
| 387 | |
| 388 | if (expr->bool > p->p_bools.nprim) { |
peter enderborg | ab48576 | 2018-06-12 10:09:00 +0200 | [diff] [blame] | 389 | pr_err("SELinux: conditional expressions uses unknown bool.\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 390 | return 0; |
| 391 | } |
| 392 | return 1; |
| 393 | } |
| 394 | |
| 395 | static int cond_read_node(struct policydb *p, struct cond_node *node, void *fp) |
| 396 | { |
Alexey Dobriyan | b5bf6c5 | 2005-09-03 15:55:17 -0700 | [diff] [blame] | 397 | __le32 buf[2]; |
| 398 | u32 len, i; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 399 | int rc; |
| 400 | struct cond_expr *expr = NULL, *last = NULL; |
| 401 | |
Namhyung Kim | f004afe | 2014-06-15 01:19:01 +0900 | [diff] [blame] | 402 | rc = next_entry(buf, fp, sizeof(u32) * 2); |
Dan Carpenter | fc5c126 | 2010-06-12 20:53:46 +0200 | [diff] [blame] | 403 | if (rc) |
Namhyung Kim | 6e51f9c | 2014-06-15 01:19:02 +0900 | [diff] [blame] | 404 | goto err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 405 | |
| 406 | node->cur_state = le32_to_cpu(buf[0]); |
| 407 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 408 | /* expr */ |
Namhyung Kim | f004afe | 2014-06-15 01:19:01 +0900 | [diff] [blame] | 409 | len = le32_to_cpu(buf[1]); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 410 | |
Eric Paris | 7c2b240 | 2008-04-18 17:38:29 -0400 | [diff] [blame] | 411 | for (i = 0; i < len; i++) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 412 | rc = next_entry(buf, fp, sizeof(u32) * 2); |
Dan Carpenter | fc5c126 | 2010-06-12 20:53:46 +0200 | [diff] [blame] | 413 | if (rc) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 414 | goto err; |
| 415 | |
Dan Carpenter | fc5c126 | 2010-06-12 20:53:46 +0200 | [diff] [blame] | 416 | rc = -ENOMEM; |
Markus Elfring | fb13a31 | 2017-01-14 11:22:12 +0100 | [diff] [blame] | 417 | expr = kzalloc(sizeof(*expr), GFP_KERNEL); |
Eric Paris | 7c2b240 | 2008-04-18 17:38:29 -0400 | [diff] [blame] | 418 | if (!expr) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 419 | goto err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 420 | |
| 421 | expr->expr_type = le32_to_cpu(buf[0]); |
| 422 | expr->bool = le32_to_cpu(buf[1]); |
| 423 | |
| 424 | if (!expr_isvalid(p, expr)) { |
Dan Carpenter | fc5c126 | 2010-06-12 20:53:46 +0200 | [diff] [blame] | 425 | rc = -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 426 | kfree(expr); |
| 427 | goto err; |
| 428 | } |
| 429 | |
Eric Paris | 7c2b240 | 2008-04-18 17:38:29 -0400 | [diff] [blame] | 430 | if (i == 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 431 | node->expr = expr; |
Eric Paris | 7c2b240 | 2008-04-18 17:38:29 -0400 | [diff] [blame] | 432 | else |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 433 | last->next = expr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 434 | last = expr; |
| 435 | } |
| 436 | |
Dan Carpenter | fc5c126 | 2010-06-12 20:53:46 +0200 | [diff] [blame] | 437 | rc = cond_read_av_list(p, fp, &node->true_list, NULL); |
| 438 | if (rc) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 439 | goto err; |
Dan Carpenter | fc5c126 | 2010-06-12 20:53:46 +0200 | [diff] [blame] | 440 | rc = cond_read_av_list(p, fp, &node->false_list, node->true_list); |
| 441 | if (rc) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 442 | goto err; |
| 443 | return 0; |
| 444 | err: |
| 445 | cond_node_destroy(node); |
Dan Carpenter | fc5c126 | 2010-06-12 20:53:46 +0200 | [diff] [blame] | 446 | return rc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 447 | } |
| 448 | |
| 449 | int cond_read_list(struct policydb *p, void *fp) |
| 450 | { |
| 451 | struct cond_node *node, *last = NULL; |
Alexey Dobriyan | b5bf6c5 | 2005-09-03 15:55:17 -0700 | [diff] [blame] | 452 | __le32 buf[1]; |
| 453 | u32 i, len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 454 | int rc; |
| 455 | |
| 456 | rc = next_entry(buf, fp, sizeof buf); |
Dan Carpenter | 5241c10 | 2010-06-12 20:51:40 +0200 | [diff] [blame] | 457 | if (rc) |
| 458 | return rc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 459 | |
| 460 | len = le32_to_cpu(buf[0]); |
| 461 | |
Yuichi Nakamura | 3232c11 | 2007-08-24 11:55:11 +0900 | [diff] [blame] | 462 | rc = avtab_alloc(&(p->te_cond_avtab), p->te_avtab.nel); |
| 463 | if (rc) |
| 464 | goto err; |
| 465 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 466 | for (i = 0; i < len; i++) { |
Dan Carpenter | 5241c10 | 2010-06-12 20:51:40 +0200 | [diff] [blame] | 467 | rc = -ENOMEM; |
Markus Elfring | fb13a31 | 2017-01-14 11:22:12 +0100 | [diff] [blame] | 468 | node = kzalloc(sizeof(*node), GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 469 | if (!node) |
| 470 | goto err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 471 | |
Dan Carpenter | 5241c10 | 2010-06-12 20:51:40 +0200 | [diff] [blame] | 472 | rc = cond_read_node(p, node, fp); |
| 473 | if (rc) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 474 | goto err; |
| 475 | |
Eric Paris | 7c2b240 | 2008-04-18 17:38:29 -0400 | [diff] [blame] | 476 | if (i == 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 477 | p->cond_list = node; |
Eric Paris | 7c2b240 | 2008-04-18 17:38:29 -0400 | [diff] [blame] | 478 | else |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 479 | last->next = node; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 480 | last = node; |
| 481 | } |
| 482 | return 0; |
| 483 | err: |
| 484 | cond_list_destroy(p->cond_list); |
Stephen Smalley | 782ebb9 | 2005-09-03 15:55:16 -0700 | [diff] [blame] | 485 | p->cond_list = NULL; |
Dan Carpenter | 5241c10 | 2010-06-12 20:51:40 +0200 | [diff] [blame] | 486 | return rc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 487 | } |
| 488 | |
Eric Paris | cee74f4 | 2010-10-13 17:50:25 -0400 | [diff] [blame] | 489 | int cond_write_bool(void *vkey, void *datum, void *ptr) |
| 490 | { |
| 491 | char *key = vkey; |
| 492 | struct cond_bool_datum *booldatum = datum; |
| 493 | struct policy_data *pd = ptr; |
| 494 | void *fp = pd->fp; |
| 495 | __le32 buf[3]; |
| 496 | u32 len; |
| 497 | int rc; |
| 498 | |
| 499 | len = strlen(key); |
| 500 | buf[0] = cpu_to_le32(booldatum->value); |
| 501 | buf[1] = cpu_to_le32(booldatum->state); |
| 502 | buf[2] = cpu_to_le32(len); |
| 503 | rc = put_entry(buf, sizeof(u32), 3, fp); |
| 504 | if (rc) |
| 505 | return rc; |
| 506 | rc = put_entry(key, 1, len, fp); |
| 507 | if (rc) |
| 508 | return rc; |
| 509 | return 0; |
| 510 | } |
| 511 | |
| 512 | /* |
| 513 | * cond_write_cond_av_list doesn't write out the av_list nodes. |
| 514 | * Instead it writes out the key/value pairs from the avtab. This |
| 515 | * is necessary because there is no way to uniquely identifying rules |
| 516 | * in the avtab so it is not possible to associate individual rules |
| 517 | * in the avtab with a conditional without saving them as part of |
| 518 | * the conditional. This means that the avtab with the conditional |
| 519 | * rules will not be saved but will be rebuilt on policy load. |
| 520 | */ |
| 521 | static int cond_write_av_list(struct policydb *p, |
| 522 | struct cond_av_list *list, struct policy_file *fp) |
| 523 | { |
| 524 | __le32 buf[1]; |
| 525 | struct cond_av_list *cur_list; |
| 526 | u32 len; |
| 527 | int rc; |
| 528 | |
| 529 | len = 0; |
| 530 | for (cur_list = list; cur_list != NULL; cur_list = cur_list->next) |
| 531 | len++; |
| 532 | |
| 533 | buf[0] = cpu_to_le32(len); |
| 534 | rc = put_entry(buf, sizeof(u32), 1, fp); |
| 535 | if (rc) |
| 536 | return rc; |
| 537 | |
| 538 | if (len == 0) |
| 539 | return 0; |
| 540 | |
| 541 | for (cur_list = list; cur_list != NULL; cur_list = cur_list->next) { |
| 542 | rc = avtab_write_item(p, cur_list->node, fp); |
| 543 | if (rc) |
| 544 | return rc; |
| 545 | } |
| 546 | |
| 547 | return 0; |
| 548 | } |
| 549 | |
James Morris | 7b98a58 | 2011-08-30 12:52:32 +1000 | [diff] [blame] | 550 | static int cond_write_node(struct policydb *p, struct cond_node *node, |
Eric Paris | cee74f4 | 2010-10-13 17:50:25 -0400 | [diff] [blame] | 551 | struct policy_file *fp) |
| 552 | { |
| 553 | struct cond_expr *cur_expr; |
| 554 | __le32 buf[2]; |
| 555 | int rc; |
| 556 | u32 len = 0; |
| 557 | |
| 558 | buf[0] = cpu_to_le32(node->cur_state); |
| 559 | rc = put_entry(buf, sizeof(u32), 1, fp); |
| 560 | if (rc) |
| 561 | return rc; |
| 562 | |
| 563 | for (cur_expr = node->expr; cur_expr != NULL; cur_expr = cur_expr->next) |
| 564 | len++; |
| 565 | |
| 566 | buf[0] = cpu_to_le32(len); |
| 567 | rc = put_entry(buf, sizeof(u32), 1, fp); |
| 568 | if (rc) |
| 569 | return rc; |
| 570 | |
| 571 | for (cur_expr = node->expr; cur_expr != NULL; cur_expr = cur_expr->next) { |
| 572 | buf[0] = cpu_to_le32(cur_expr->expr_type); |
| 573 | buf[1] = cpu_to_le32(cur_expr->bool); |
| 574 | rc = put_entry(buf, sizeof(u32), 2, fp); |
| 575 | if (rc) |
| 576 | return rc; |
| 577 | } |
| 578 | |
| 579 | rc = cond_write_av_list(p, node->true_list, fp); |
| 580 | if (rc) |
| 581 | return rc; |
| 582 | rc = cond_write_av_list(p, node->false_list, fp); |
| 583 | if (rc) |
| 584 | return rc; |
| 585 | |
| 586 | return 0; |
| 587 | } |
| 588 | |
| 589 | int cond_write_list(struct policydb *p, struct cond_node *list, void *fp) |
| 590 | { |
| 591 | struct cond_node *cur; |
| 592 | u32 len; |
| 593 | __le32 buf[1]; |
| 594 | int rc; |
| 595 | |
| 596 | len = 0; |
| 597 | for (cur = list; cur != NULL; cur = cur->next) |
| 598 | len++; |
| 599 | buf[0] = cpu_to_le32(len); |
| 600 | rc = put_entry(buf, sizeof(u32), 1, fp); |
| 601 | if (rc) |
| 602 | return rc; |
| 603 | |
| 604 | for (cur = list; cur != NULL; cur = cur->next) { |
| 605 | rc = cond_write_node(p, cur, fp); |
| 606 | if (rc) |
| 607 | return rc; |
| 608 | } |
| 609 | |
| 610 | return 0; |
| 611 | } |
Jeff Vander Stoep | fa1aa14 | 2015-07-10 17:19:56 -0400 | [diff] [blame] | 612 | |
| 613 | void cond_compute_xperms(struct avtab *ctab, struct avtab_key *key, |
| 614 | struct extended_perms_decision *xpermd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 615 | { |
| 616 | struct avtab_node *node; |
| 617 | |
Jeff Vander Stoep | fa1aa14 | 2015-07-10 17:19:56 -0400 | [diff] [blame] | 618 | if (!ctab || !key || !xpermd) |
| 619 | return; |
| 620 | |
| 621 | for (node = avtab_search_node(ctab, key); node; |
| 622 | node = avtab_search_node_next(node, key->specified)) { |
| 623 | if (node->key.specified & AVTAB_ENABLED) |
| 624 | services_compute_xperms_decision(xpermd, node); |
| 625 | } |
| 626 | return; |
| 627 | |
| 628 | } |
| 629 | /* Determine whether additional permissions are granted by the conditional |
| 630 | * av table, and if so, add them to the result |
| 631 | */ |
| 632 | void cond_compute_av(struct avtab *ctab, struct avtab_key *key, |
| 633 | struct av_decision *avd, struct extended_perms *xperms) |
| 634 | { |
| 635 | struct avtab_node *node; |
| 636 | |
Stephen Smalley | f3bef67 | 2015-11-23 16:07:41 -0500 | [diff] [blame] | 637 | if (!ctab || !key || !avd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 638 | return; |
| 639 | |
Vesa-Matti Kari | dbc74c6 | 2008-08-07 03:18:20 +0300 | [diff] [blame] | 640 | for (node = avtab_search_node(ctab, key); node; |
Stephen Smalley | 782ebb9 | 2005-09-03 15:55:16 -0700 | [diff] [blame] | 641 | node = avtab_search_node_next(node, key->specified)) { |
Eric Paris | 7c2b240 | 2008-04-18 17:38:29 -0400 | [diff] [blame] | 642 | if ((u16)(AVTAB_ALLOWED|AVTAB_ENABLED) == |
| 643 | (node->key.specified & (AVTAB_ALLOWED|AVTAB_ENABLED))) |
Jeff Vander Stoep | fa1aa14 | 2015-07-10 17:19:56 -0400 | [diff] [blame] | 644 | avd->allowed |= node->datum.u.data; |
Eric Paris | 7c2b240 | 2008-04-18 17:38:29 -0400 | [diff] [blame] | 645 | if ((u16)(AVTAB_AUDITDENY|AVTAB_ENABLED) == |
| 646 | (node->key.specified & (AVTAB_AUDITDENY|AVTAB_ENABLED))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 647 | /* Since a '0' in an auditdeny mask represents a |
| 648 | * permission we do NOT want to audit (dontaudit), we use |
| 649 | * the '&' operand to ensure that all '0's in the mask |
| 650 | * are retained (much unlike the allow and auditallow cases). |
| 651 | */ |
Jeff Vander Stoep | fa1aa14 | 2015-07-10 17:19:56 -0400 | [diff] [blame] | 652 | avd->auditdeny &= node->datum.u.data; |
Eric Paris | 7c2b240 | 2008-04-18 17:38:29 -0400 | [diff] [blame] | 653 | if ((u16)(AVTAB_AUDITALLOW|AVTAB_ENABLED) == |
| 654 | (node->key.specified & (AVTAB_AUDITALLOW|AVTAB_ENABLED))) |
Jeff Vander Stoep | fa1aa14 | 2015-07-10 17:19:56 -0400 | [diff] [blame] | 655 | avd->auditallow |= node->datum.u.data; |
Stephen Smalley | f3bef67 | 2015-11-23 16:07:41 -0500 | [diff] [blame] | 656 | if (xperms && (node->key.specified & AVTAB_ENABLED) && |
Jeff Vander Stoep | fa1aa14 | 2015-07-10 17:19:56 -0400 | [diff] [blame] | 657 | (node->key.specified & AVTAB_XPERMS)) |
| 658 | services_compute_xperms_drivers(xperms, node); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 659 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 660 | } |