| 1 | |
| 2 | |
| 3 | *
|
| 4 | * Copyright 2003-2004 Red Hat, Inc.
|
| 5 | * Copyright 2005 Hewlett-Packard Development Company, L.P.
|
| 6 | * Copyright 2005 IBM Corporation
|
| 7 |
|
| 8 |
|
| 9 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
|
| 10 |
|
| 11 | #include <linux/kernel.h>
|
| 12 | #include <linux/audit.h>
|
| 13 | #include <linux/kthread.h>
|
| 14 | #include <linux/mutex.h>
|
| 15 | #include <linux/fs.h>
|
| 16 | #include <linux/namei.h>
|
| 17 | #include <linux/netlink.h>
|
| 18 | #include <linux/sched.h>
|
| 19 | #include <linux/slab.h>
|
| 20 | #include <linux/security.h>
|
| 21 | #include <net/net_namespace.h>
|
| 22 | #include <net/sock.h>
|
| 23 | #include "audit.h"
|
| 24 |
|
| 25 | |
| 26 | * Locking model:
|
| 27 | *
|
| 28 | * audit_filter_mutex:
|
| 29 | * Synchronizes writes and blocking reads of audit's filterlist
|
| 30 | * data. Rcu is used to traverse the filterlist and access
|
| 31 | * contents of structs audit_entry, audit_watch and opaque
|
| 32 | * LSM rules during filtering. If modified, these structures
|
| 33 | * must be copied and replace their counterparts in the filterlist.
|
| 34 | * An audit_parent struct is not accessed during filtering, so may
|
| 35 | * be written directly provided audit_filter_mutex is held.
|
| 36 |
|
| 37 |
|
| 38 |
|
| 39 | struct list_head audit_filter_list[AUDIT_NR_FILTERS] = {
|
| 40 | LIST_HEAD_INIT(audit_filter_list[0]),
|
| 41 | LIST_HEAD_INIT(audit_filter_list[1]),
|
| 42 | LIST_HEAD_INIT(audit_filter_list[2]),
|
| 43 | LIST_HEAD_INIT(audit_filter_list[3]),
|
| 44 | LIST_HEAD_INIT(audit_filter_list[4]),
|
| 45 | LIST_HEAD_INIT(audit_filter_list[5]),
|
| 46 | LIST_HEAD_INIT(audit_filter_list[6]),
|
| 47 | LIST_HEAD_INIT(audit_filter_list[7]),
|
| 48 | #if AUDIT_NR_FILTERS != 8
|
| 49 | #error Fix audit_filter_list initialiser
|
| 50 | #endif
|
| 51 | };
|
| 52 | static struct list_head audit_rules_list[AUDIT_NR_FILTERS] = {
|
| 53 | LIST_HEAD_INIT(audit_rules_list[0]),
|
| 54 | LIST_HEAD_INIT(audit_rules_list[1]),
|
| 55 | LIST_HEAD_INIT(audit_rules_list[2]),
|
| 56 | LIST_HEAD_INIT(audit_rules_list[3]),
|
| 57 | LIST_HEAD_INIT(audit_rules_list[4]),
|
| 58 | LIST_HEAD_INIT(audit_rules_list[5]),
|
| 59 | LIST_HEAD_INIT(audit_rules_list[6]),
|
| 60 | LIST_HEAD_INIT(audit_rules_list[7]),
|
| 61 | };
|
| 62 |
|
| 63 | DEFINE_MUTEX(audit_filter_mutex);
|
| 64 |
|
| 65 | static void audit_free_lsm_field(struct audit_field *f)
|
| 66 | {
|
| 67 | switch (f->type) {
|
| 68 | case AUDIT_SUBJ_USER:
|
| 69 | case AUDIT_SUBJ_ROLE:
|
| 70 | case AUDIT_SUBJ_TYPE:
|
| 71 | case AUDIT_SUBJ_SEN:
|
| 72 | case AUDIT_SUBJ_CLR:
|
| 73 | case AUDIT_OBJ_USER:
|
| 74 | case AUDIT_OBJ_ROLE:
|
| 75 | case AUDIT_OBJ_TYPE:
|
| 76 | case AUDIT_OBJ_LEV_LOW:
|
| 77 | case AUDIT_OBJ_LEV_HIGH:
|
| 78 | kfree(f->lsm_str);
|
| 79 | security_audit_rule_free(f->lsm_rule);
|
| 80 | }
|
| 81 | }
|
| 82 |
|
| 83 | static inline void audit_free_rule(struct audit_entry *e)
|
| 84 | {
|
| 85 | int i;
|
| 86 | struct audit_krule *erule = &e->rule;
|
| 87 |
|
| 88 |
|
| 89 | if (erule->watch)
|
| 90 | audit_put_watch(erule->watch);
|
| 91 | if (erule->fields)
|
| 92 | for (i = 0; i < erule->field_count; i++)
|
| 93 | audit_free_lsm_field(&erule->fields[i]);
|
| 94 | kfree(erule->fields);
|
| 95 | kfree(erule->filterkey);
|
| 96 | kfree(e);
|
| 97 | }
|
| 98 |
|
| 99 | void audit_free_rule_rcu(struct rcu_head *head)
|
| 100 | {
|
| 101 | struct audit_entry *e = container_of(head, struct audit_entry, rcu);
|
| 102 | audit_free_rule(e);
|
| 103 | }
|
| 104 |
|
| 105 |
|
| 106 | static inline struct audit_entry *audit_init_entry(u32 field_count)
|
| 107 | {
|
| 108 | struct audit_entry *entry;
|
| 109 | struct audit_field *fields;
|
| 110 |
|
| 111 | entry = kzalloc_obj(*entry);
|
| 112 | if (unlikely(!entry))
|
| 113 | return NULL;
|
| 114 |
|
| 115 | fields = kzalloc_objs(*fields, field_count);
|
| 116 | if (unlikely(!fields)) {
|
| 117 | kfree(entry);
|
| 118 | return NULL;
|
| 119 | }
|
| 120 | entry->rule.fields = fields;
|
| 121 |
|
| 122 | return entry;
|
| 123 | }
|
| 124 |
|
| 125 | |
| 126 | * buffer.
|
| 127 | char *audit_unpack_string(void **bufp, size_t *remain, size_t len)
|
| 128 | {
|
| 129 | char *str;
|
| 130 |
|
| 131 | if (!*bufp || (len == 0) || (len > *remain))
|
| 132 | return ERR_PTR(-EINVAL);
|
| 133 |
|
| 134 | |
| 135 | * defines the longest valid length.
|
| 136 |
|
| 137 | if (len > PATH_MAX)
|
| 138 | return ERR_PTR(-ENAMETOOLONG);
|
| 139 |
|
| 140 | str = kmalloc(len + 1, GFP_KERNEL);
|
| 141 | if (unlikely(!str))
|
| 142 | return ERR_PTR(-ENOMEM);
|
| 143 |
|
| 144 | memcpy(str, *bufp, len);
|
| 145 | str[len] = 0;
|
| 146 | *bufp += len;
|
| 147 | *remain -= len;
|
| 148 |
|
| 149 | return str;
|
| 150 | }
|
| 151 |
|
| 152 |
|
| 153 | static inline int audit_to_inode(struct audit_krule *krule,
|
| 154 | struct audit_field *f)
|
| 155 | {
|
| 156 | if ((krule->listnr != AUDIT_FILTER_EXIT &&
|
| 157 | krule->listnr != AUDIT_FILTER_URING_EXIT) ||
|
| 158 | krule->inode_f || krule->watch || krule->tree ||
|
| 159 | (f->op != Audit_equal && f->op != Audit_not_equal))
|
| 160 | return -EINVAL;
|
| 161 |
|
| 162 | krule->inode_f = f;
|
| 163 | return 0;
|
| 164 | }
|
| 165 |
|
| 166 | static __u32 *classes[AUDIT_SYSCALL_CLASSES];
|
| 167 |
|
| 168 | int __init audit_register_class(int class, unsigned int *list)
|
| 169 | {
|
| 170 | __u32 *p = kcalloc(AUDIT_BITMASK_SIZE, sizeof(__u32), GFP_KERNEL);
|
| 171 | if (!p)
|
| 172 | return -ENOMEM;
|
| 173 | while (*list != ~0U) {
|
| 174 | unsigned int n = *list++;
|
| 175 | if (n >= AUDIT_BITMASK_SIZE * 32 - AUDIT_SYSCALL_CLASSES) {
|
| 176 | kfree(p);
|
| 177 | return -EINVAL;
|
| 178 | }
|
| 179 | p[AUDIT_WORD(n)] |= AUDIT_BIT(n);
|
| 180 | }
|
| 181 | if (class >= AUDIT_SYSCALL_CLASSES || classes[class]) {
|
| 182 | kfree(p);
|
| 183 | return -EINVAL;
|
| 184 | }
|
| 185 | classes[class] = p;
|
| 186 | return 0;
|
| 187 | }
|
| 188 |
|
| 189 | int audit_match_class(int class, unsigned int syscall)
|
| 190 | {
|
| 191 | if (unlikely(syscall >= AUDIT_BITMASK_SIZE * 32))
|
| 192 | return 0;
|
| 193 | if (unlikely(class >= AUDIT_SYSCALL_CLASSES || !classes[class]))
|
| 194 | return 0;
|
| 195 | return classes[class][AUDIT_WORD(syscall)] & AUDIT_BIT(syscall);
|
| 196 | }
|
| 197 |
|
| 198 | #ifdef CONFIG_AUDITSYSCALL
|
| 199 | static inline int audit_match_class_bits(int class, u32 *mask)
|
| 200 | {
|
| 201 | int i;
|
| 202 |
|
| 203 | if (classes[class]) {
|
| 204 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
|
| 205 | if (mask[i] & classes[class][i])
|
| 206 | return 0;
|
| 207 | }
|
| 208 | return 1;
|
| 209 | }
|
| 210 |
|
| 211 | static int audit_match_signal(struct audit_entry *entry)
|
| 212 | {
|
| 213 | struct audit_field *arch = entry->rule.arch_f;
|
| 214 |
|
| 215 | if (!arch) {
|
| 216 | |
| 217 | * as syscall number alone is ambiguous.
|
| 218 | return (audit_match_class_bits(AUDIT_CLASS_SIGNAL,
|
| 219 | entry->rule.mask) &&
|
| 220 | audit_match_class_bits(AUDIT_CLASS_SIGNAL_32,
|
| 221 | entry->rule.mask));
|
| 222 | }
|
| 223 |
|
| 224 | switch (audit_classify_arch(arch->val)) {
|
| 225 | case 0:
|
| 226 | return (audit_match_class_bits(AUDIT_CLASS_SIGNAL,
|
| 227 | entry->rule.mask));
|
| 228 | case 1:
|
| 229 | return (audit_match_class_bits(AUDIT_CLASS_SIGNAL_32,
|
| 230 | entry->rule.mask));
|
| 231 | default:
|
| 232 | return 1;
|
| 233 | }
|
| 234 | }
|
| 235 | #endif
|
| 236 |
|
| 237 |
|
| 238 | static inline struct audit_entry *audit_to_entry_common(struct audit_rule_data *rule)
|
| 239 | {
|
| 240 | unsigned int listnr;
|
| 241 | struct audit_entry *entry;
|
| 242 | int i, err;
|
| 243 |
|
| 244 | err = -EINVAL;
|
| 245 | listnr = rule->flags & ~AUDIT_FILTER_PREPEND;
|
| 246 | switch (listnr) {
|
| 247 | default:
|
| 248 | goto exit_err;
|
| 249 | #ifdef CONFIG_AUDITSYSCALL
|
| 250 | case AUDIT_FILTER_ENTRY:
|
| 251 | pr_err("AUDIT_FILTER_ENTRY is deprecated\n");
|
| 252 | goto exit_err;
|
| 253 | case AUDIT_FILTER_EXIT:
|
| 254 | case AUDIT_FILTER_URING_EXIT:
|
| 255 | case AUDIT_FILTER_TASK:
|
| 256 | #endif
|
| 257 | case AUDIT_FILTER_USER:
|
| 258 | case AUDIT_FILTER_EXCLUDE:
|
| 259 | case AUDIT_FILTER_FS:
|
| 260 | ;
|
| 261 | }
|
| 262 | if (unlikely(rule->action == AUDIT_POSSIBLE)) {
|
| 263 | pr_err("AUDIT_POSSIBLE is deprecated\n");
|
| 264 | goto exit_err;
|
| 265 | }
|
| 266 | if (rule->action != AUDIT_NEVER && rule->action != AUDIT_ALWAYS)
|
| 267 | goto exit_err;
|
| 268 | if (rule->field_count > AUDIT_MAX_FIELDS)
|
| 269 | goto exit_err;
|
| 270 |
|
| 271 | err = -ENOMEM;
|
| 272 | entry = audit_init_entry(rule->field_count);
|
| 273 | if (!entry)
|
| 274 | goto exit_err;
|
| 275 |
|
| 276 | entry->rule.flags = rule->flags & AUDIT_FILTER_PREPEND;
|
| 277 | entry->rule.listnr = listnr;
|
| 278 | entry->rule.action = rule->action;
|
| 279 | entry->rule.field_count = rule->field_count;
|
| 280 |
|
| 281 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
|
| 282 | entry->rule.mask[i] = rule->mask[i];
|
| 283 |
|
| 284 | for (i = 0; i < AUDIT_SYSCALL_CLASSES; i++) {
|
| 285 | int bit = AUDIT_BITMASK_SIZE * 32 - i - 1;
|
| 286 | __u32 *p = &entry->rule.mask[AUDIT_WORD(bit)];
|
| 287 | __u32 *class;
|
| 288 |
|
| 289 | if (!(*p & AUDIT_BIT(bit)))
|
| 290 | continue;
|
| 291 | *p &= ~AUDIT_BIT(bit);
|
| 292 | class = classes[i];
|
| 293 | if (class) {
|
| 294 | int j;
|
| 295 | for (j = 0; j < AUDIT_BITMASK_SIZE; j++)
|
| 296 | entry->rule.mask[j] |= class[j];
|
| 297 | }
|
| 298 | }
|
| 299 |
|
| 300 | return entry;
|
| 301 |
|
| 302 | exit_err:
|
| 303 | return ERR_PTR(err);
|
| 304 | }
|
| 305 |
|
| 306 | static u32 audit_ops[] = {
|
| 307 | [Audit_equal] = AUDIT_EQUAL,
|
| 308 | [Audit_not_equal] = AUDIT_NOT_EQUAL,
|
| 309 | [Audit_bitmask] = AUDIT_BIT_MASK,
|
| 310 | [Audit_bittest] = AUDIT_BIT_TEST,
|
| 311 | [Audit_lt] = AUDIT_LESS_THAN,
|
| 312 | [Audit_gt] = AUDIT_GREATER_THAN,
|
| 313 | [Audit_le] = AUDIT_LESS_THAN_OR_EQUAL,
|
| 314 | [Audit_ge] = AUDIT_GREATER_THAN_OR_EQUAL,
|
| 315 | };
|
| 316 |
|
| 317 | static u32 audit_to_op(u32 op)
|
| 318 | {
|
| 319 | u32 n;
|
| 320 | for (n = Audit_equal; n < Audit_bad && audit_ops[n] != op; n++)
|
| 321 | ;
|
| 322 | return n;
|
| 323 | }
|
| 324 |
|
| 325 |
|
| 326 | static int audit_field_valid(struct audit_entry *entry, struct audit_field *f)
|
| 327 | {
|
| 328 | switch (f->type) {
|
| 329 | case AUDIT_MSGTYPE:
|
| 330 | if (entry->rule.listnr != AUDIT_FILTER_EXCLUDE &&
|
| 331 | entry->rule.listnr != AUDIT_FILTER_USER)
|
| 332 | return -EINVAL;
|
| 333 | break;
|
| 334 | case AUDIT_FSTYPE:
|
| 335 | if (entry->rule.listnr != AUDIT_FILTER_FS)
|
| 336 | return -EINVAL;
|
| 337 | break;
|
| 338 | case AUDIT_PERM:
|
| 339 | if (entry->rule.listnr == AUDIT_FILTER_URING_EXIT)
|
| 340 | return -EINVAL;
|
| 341 | break;
|
| 342 | }
|
| 343 |
|
| 344 | switch (entry->rule.listnr) {
|
| 345 | case AUDIT_FILTER_FS:
|
| 346 | switch (f->type) {
|
| 347 | case AUDIT_FSTYPE:
|
| 348 | case AUDIT_FILTERKEY:
|
| 349 | break;
|
| 350 | default:
|
| 351 | return -EINVAL;
|
| 352 | }
|
| 353 | }
|
| 354 |
|
| 355 |
|
| 356 | switch (f->type) {
|
| 357 | case AUDIT_ARG0:
|
| 358 | case AUDIT_ARG1:
|
| 359 | case AUDIT_ARG2:
|
| 360 | case AUDIT_ARG3:
|
| 361 | case AUDIT_PERS:
|
| 362 | case AUDIT_DEVMINOR:
|
| 363 |
|
| 364 | break;
|
| 365 | case AUDIT_UID:
|
| 366 | case AUDIT_EUID:
|
| 367 | case AUDIT_SUID:
|
| 368 | case AUDIT_FSUID:
|
| 369 | case AUDIT_LOGINUID:
|
| 370 | case AUDIT_OBJ_UID:
|
| 371 | case AUDIT_GID:
|
| 372 | case AUDIT_EGID:
|
| 373 | case AUDIT_SGID:
|
| 374 | case AUDIT_FSGID:
|
| 375 | case AUDIT_OBJ_GID:
|
| 376 | case AUDIT_PID:
|
| 377 | case AUDIT_MSGTYPE:
|
| 378 | case AUDIT_PPID:
|
| 379 | case AUDIT_DEVMAJOR:
|
| 380 | case AUDIT_EXIT:
|
| 381 | case AUDIT_SUCCESS:
|
| 382 | case AUDIT_INODE:
|
| 383 | case AUDIT_SESSIONID:
|
| 384 | case AUDIT_SUBJ_SEN:
|
| 385 | case AUDIT_SUBJ_CLR:
|
| 386 | case AUDIT_OBJ_LEV_LOW:
|
| 387 | case AUDIT_OBJ_LEV_HIGH:
|
| 388 | case AUDIT_SADDR_FAM:
|
| 389 |
|
| 390 | if (f->op == Audit_bitmask || f->op == Audit_bittest)
|
| 391 | return -EINVAL;
|
| 392 | break;
|
| 393 | case AUDIT_SUBJ_USER:
|
| 394 | case AUDIT_SUBJ_ROLE:
|
| 395 | case AUDIT_SUBJ_TYPE:
|
| 396 | case AUDIT_OBJ_USER:
|
| 397 | case AUDIT_OBJ_ROLE:
|
| 398 | case AUDIT_OBJ_TYPE:
|
| 399 | case AUDIT_WATCH:
|
| 400 | case AUDIT_DIR:
|
| 401 | case AUDIT_FILTERKEY:
|
| 402 | case AUDIT_LOGINUID_SET:
|
| 403 | case AUDIT_ARCH:
|
| 404 | case AUDIT_FSTYPE:
|
| 405 | case AUDIT_PERM:
|
| 406 | case AUDIT_FILETYPE:
|
| 407 | case AUDIT_FIELD_COMPARE:
|
| 408 | case AUDIT_EXE:
|
| 409 |
|
| 410 | if (f->op != Audit_not_equal && f->op != Audit_equal)
|
| 411 | return -EINVAL;
|
| 412 | break;
|
| 413 | default:
|
| 414 |
|
| 415 | return -EINVAL;
|
| 416 | }
|
| 417 |
|
| 418 |
|
| 419 | switch (f->type) {
|
| 420 | case AUDIT_LOGINUID_SET:
|
| 421 | if ((f->val != 0) && (f->val != 1))
|
| 422 | return -EINVAL;
|
| 423 | break;
|
| 424 | case AUDIT_PERM:
|
| 425 | if (f->val & ~15)
|
| 426 | return -EINVAL;
|
| 427 | break;
|
| 428 | case AUDIT_FILETYPE:
|
| 429 | if (f->val & ~S_IFMT)
|
| 430 | return -EINVAL;
|
| 431 | break;
|
| 432 | case AUDIT_FIELD_COMPARE:
|
| 433 | if (f->val > AUDIT_MAX_FIELD_COMPARE)
|
| 434 | return -EINVAL;
|
| 435 | break;
|
| 436 | case AUDIT_SADDR_FAM:
|
| 437 | if (f->val >= AF_MAX)
|
| 438 | return -EINVAL;
|
| 439 | break;
|
| 440 | default:
|
| 441 | break;
|
| 442 | }
|
| 443 |
|
| 444 | return 0;
|
| 445 | }
|
| 446 |
|
| 447 |
|
| 448 | static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
|
| 449 | size_t datasz)
|
| 450 | {
|
| 451 | int err = 0;
|
| 452 | struct audit_entry *entry;
|
| 453 | void *bufp;
|
| 454 | size_t remain = datasz - sizeof(struct audit_rule_data);
|
| 455 | int i;
|
| 456 | char *str;
|
| 457 | struct audit_fsnotify_mark *audit_mark;
|
| 458 |
|
| 459 | entry = audit_to_entry_common(data);
|
| 460 | if (IS_ERR(entry))
|
| 461 | goto exit_nofree;
|
| 462 |
|
| 463 | bufp = data->buf;
|
| 464 | for (i = 0; i < data->field_count; i++) {
|
| 465 | struct audit_field *f = &entry->rule.fields[i];
|
| 466 | u32 f_val;
|
| 467 |
|
| 468 | err = -EINVAL;
|
| 469 |
|
| 470 | f->op = audit_to_op(data->fieldflags[i]);
|
| 471 | if (f->op == Audit_bad)
|
| 472 | goto exit_free;
|
| 473 |
|
| 474 | f->type = data->fields[i];
|
| 475 | f_val = data->values[i];
|
| 476 |
|
| 477 |
|
| 478 | if ((f->type == AUDIT_LOGINUID) && (f_val == AUDIT_UID_UNSET)) {
|
| 479 | f->type = AUDIT_LOGINUID_SET;
|
| 480 | f_val = 0;
|
| 481 | entry->rule.pflags |= AUDIT_LOGINUID_LEGACY;
|
| 482 | }
|
| 483 |
|
| 484 | err = audit_field_valid(entry, f);
|
| 485 | if (err)
|
| 486 | goto exit_free;
|
| 487 |
|
| 488 | err = -EINVAL;
|
| 489 | switch (f->type) {
|
| 490 | case AUDIT_LOGINUID:
|
| 491 | case AUDIT_UID:
|
| 492 | case AUDIT_EUID:
|
| 493 | case AUDIT_SUID:
|
| 494 | case AUDIT_FSUID:
|
| 495 | case AUDIT_OBJ_UID:
|
| 496 | f->uid = make_kuid(current_user_ns(), f_val);
|
| 497 | if (!uid_valid(f->uid))
|
| 498 | goto exit_free;
|
| 499 | break;
|
| 500 | case AUDIT_GID:
|
| 501 | case AUDIT_EGID:
|
| 502 | case AUDIT_SGID:
|
| 503 | case AUDIT_FSGID:
|
| 504 | case AUDIT_OBJ_GID:
|
| 505 | f->gid = make_kgid(current_user_ns(), f_val);
|
| 506 | if (!gid_valid(f->gid))
|
| 507 | goto exit_free;
|
| 508 | break;
|
| 509 | case AUDIT_ARCH:
|
| 510 | f->val = f_val;
|
| 511 | entry->rule.arch_f = f;
|
| 512 | break;
|
| 513 | case AUDIT_SUBJ_USER:
|
| 514 | case AUDIT_SUBJ_ROLE:
|
| 515 | case AUDIT_SUBJ_TYPE:
|
| 516 | case AUDIT_SUBJ_SEN:
|
| 517 | case AUDIT_SUBJ_CLR:
|
| 518 | case AUDIT_OBJ_USER:
|
| 519 | case AUDIT_OBJ_ROLE:
|
| 520 | case AUDIT_OBJ_TYPE:
|
| 521 | case AUDIT_OBJ_LEV_LOW:
|
| 522 | case AUDIT_OBJ_LEV_HIGH:
|
| 523 | str = audit_unpack_string(&bufp, &remain, f_val);
|
| 524 | if (IS_ERR(str)) {
|
| 525 | err = PTR_ERR(str);
|
| 526 | goto exit_free;
|
| 527 | }
|
| 528 | entry->rule.buflen += f_val;
|
| 529 | f->lsm_str = str;
|
| 530 | err = security_audit_rule_init(f->type, f->op, str,
|
| 531 | (void **)&f->lsm_rule,
|
| 532 | GFP_KERNEL);
|
| 533 | |
| 534 | * become valid after a policy reload.
|
| 535 | if (err == -EINVAL) {
|
| 536 | pr_warn("audit rule for LSM \'%s\' is invalid\n",
|
| 537 | str);
|
| 538 | err = 0;
|
| 539 | } else if (err)
|
| 540 | goto exit_free;
|
| 541 | break;
|
| 542 | case AUDIT_WATCH:
|
| 543 | str = audit_unpack_string(&bufp, &remain, f_val);
|
| 544 | if (IS_ERR(str)) {
|
| 545 | err = PTR_ERR(str);
|
| 546 | goto exit_free;
|
| 547 | }
|
| 548 | err = audit_to_watch(&entry->rule, str, f_val, f->op);
|
| 549 | if (err) {
|
| 550 | kfree(str);
|
| 551 | goto exit_free;
|
| 552 | }
|
| 553 | entry->rule.buflen += f_val;
|
| 554 | break;
|
| 555 | case AUDIT_DIR:
|
| 556 | str = audit_unpack_string(&bufp, &remain, f_val);
|
| 557 | if (IS_ERR(str)) {
|
| 558 | err = PTR_ERR(str);
|
| 559 | goto exit_free;
|
| 560 | }
|
| 561 | err = audit_make_tree(&entry->rule, str, f->op);
|
| 562 | kfree(str);
|
| 563 | if (err)
|
| 564 | goto exit_free;
|
| 565 | entry->rule.buflen += f_val;
|
| 566 | break;
|
| 567 | case AUDIT_INODE:
|
| 568 | f->val = f_val;
|
| 569 | err = audit_to_inode(&entry->rule, f);
|
| 570 | if (err)
|
| 571 | goto exit_free;
|
| 572 | break;
|
| 573 | case AUDIT_FILTERKEY:
|
| 574 | if (entry->rule.filterkey || f_val > AUDIT_MAX_KEY_LEN)
|
| 575 | goto exit_free;
|
| 576 | str = audit_unpack_string(&bufp, &remain, f_val);
|
| 577 | if (IS_ERR(str)) {
|
| 578 | err = PTR_ERR(str);
|
| 579 | goto exit_free;
|
| 580 | }
|
| 581 | entry->rule.buflen += f_val;
|
| 582 | entry->rule.filterkey = str;
|
| 583 | break;
|
| 584 | case AUDIT_EXE:
|
| 585 | if (entry->rule.exe || f_val > PATH_MAX)
|
| 586 | goto exit_free;
|
| 587 | str = audit_unpack_string(&bufp, &remain, f_val);
|
| 588 | if (IS_ERR(str)) {
|
| 589 | err = PTR_ERR(str);
|
| 590 | goto exit_free;
|
| 591 | }
|
| 592 | audit_mark = audit_alloc_mark(&entry->rule, str, f_val, NULL);
|
| 593 | if (IS_ERR(audit_mark)) {
|
| 594 | kfree(str);
|
| 595 | err = PTR_ERR(audit_mark);
|
| 596 | goto exit_free;
|
| 597 | }
|
| 598 | entry->rule.buflen += f_val;
|
| 599 | entry->rule.exe = audit_mark;
|
| 600 | break;
|
| 601 | default:
|
| 602 | f->val = f_val;
|
| 603 | break;
|
| 604 | }
|
| 605 | }
|
| 606 |
|
| 607 | if (entry->rule.inode_f && entry->rule.inode_f->op == Audit_not_equal)
|
| 608 | entry->rule.inode_f = NULL;
|
| 609 |
|
| 610 | exit_nofree:
|
| 611 | return entry;
|
| 612 |
|
| 613 | exit_free:
|
| 614 | if (entry->rule.tree)
|
| 615 | audit_put_tree(entry->rule.tree);
|
| 616 | if (entry->rule.exe)
|
| 617 | audit_remove_mark(entry->rule.exe);
|
| 618 | audit_free_rule(entry);
|
| 619 | return ERR_PTR(err);
|
| 620 | }
|
| 621 |
|
| 622 |
|
| 623 | static inline size_t audit_pack_string(void **bufp, const char *str)
|
| 624 | {
|
| 625 | size_t len = strlen(str);
|
| 626 |
|
| 627 | memcpy(*bufp, str, len);
|
| 628 | *bufp += len;
|
| 629 |
|
| 630 | return len;
|
| 631 | }
|
| 632 |
|
| 633 |
|
| 634 | static struct audit_rule_data *audit_krule_to_data(struct audit_krule *krule)
|
| 635 | {
|
| 636 | struct audit_rule_data *data;
|
| 637 | void *bufp;
|
| 638 | int i;
|
| 639 |
|
| 640 | data = kzalloc_flex(*data, buf, krule->buflen);
|
| 641 | if (unlikely(!data))
|
| 642 | return NULL;
|
| 643 |
|
| 644 | data->flags = krule->flags | krule->listnr;
|
| 645 | data->action = krule->action;
|
| 646 | data->field_count = krule->field_count;
|
| 647 | bufp = data->buf;
|
| 648 | for (i = 0; i < data->field_count; i++) {
|
| 649 | struct audit_field *f = &krule->fields[i];
|
| 650 |
|
| 651 | data->fields[i] = f->type;
|
| 652 | data->fieldflags[i] = audit_ops[f->op];
|
| 653 | switch (f->type) {
|
| 654 | case AUDIT_SUBJ_USER:
|
| 655 | case AUDIT_SUBJ_ROLE:
|
| 656 | case AUDIT_SUBJ_TYPE:
|
| 657 | case AUDIT_SUBJ_SEN:
|
| 658 | case AUDIT_SUBJ_CLR:
|
| 659 | case AUDIT_OBJ_USER:
|
| 660 | case AUDIT_OBJ_ROLE:
|
| 661 | case AUDIT_OBJ_TYPE:
|
| 662 | case AUDIT_OBJ_LEV_LOW:
|
| 663 | case AUDIT_OBJ_LEV_HIGH:
|
| 664 | data->buflen += data->values[i] =
|
| 665 | audit_pack_string(&bufp, f->lsm_str);
|
| 666 | break;
|
| 667 | case AUDIT_WATCH:
|
| 668 | data->buflen += data->values[i] =
|
| 669 | audit_pack_string(&bufp,
|
| 670 | audit_watch_path(krule->watch));
|
| 671 | break;
|
| 672 | case AUDIT_DIR:
|
| 673 | data->buflen += data->values[i] =
|
| 674 | audit_pack_string(&bufp,
|
| 675 | audit_tree_path(krule->tree));
|
| 676 | break;
|
| 677 | case AUDIT_FILTERKEY:
|
| 678 | data->buflen += data->values[i] =
|
| 679 | audit_pack_string(&bufp, krule->filterkey);
|
| 680 | break;
|
| 681 | case AUDIT_EXE:
|
| 682 | data->buflen += data->values[i] =
|
| 683 | audit_pack_string(&bufp, audit_mark_path(krule->exe));
|
| 684 | break;
|
| 685 | case AUDIT_LOGINUID_SET:
|
| 686 | if (krule->pflags & AUDIT_LOGINUID_LEGACY && !f->val) {
|
| 687 | data->fields[i] = AUDIT_LOGINUID;
|
| 688 | data->values[i] = AUDIT_UID_UNSET;
|
| 689 | break;
|
| 690 | }
|
| 691 | fallthrough;
|
| 692 | default:
|
| 693 | data->values[i] = f->val;
|
| 694 | }
|
| 695 | }
|
| 696 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
|
| 697 | data->mask[i] = krule->mask[i];
|
| 698 |
|
| 699 | return data;
|
| 700 | }
|
| 701 |
|
| 702 | |
| 703 | * don't match.
|
| 704 | static int audit_compare_rule(struct audit_krule *a, struct audit_krule *b)
|
| 705 | {
|
| 706 | int i;
|
| 707 |
|
| 708 | if (a->flags != b->flags ||
|
| 709 | a->pflags != b->pflags ||
|
| 710 | a->listnr != b->listnr ||
|
| 711 | a->action != b->action ||
|
| 712 | a->field_count != b->field_count)
|
| 713 | return 1;
|
| 714 |
|
| 715 | for (i = 0; i < a->field_count; i++) {
|
| 716 | if (a->fields[i].type != b->fields[i].type ||
|
| 717 | a->fields[i].op != b->fields[i].op)
|
| 718 | return 1;
|
| 719 |
|
| 720 | switch (a->fields[i].type) {
|
| 721 | case AUDIT_SUBJ_USER:
|
| 722 | case AUDIT_SUBJ_ROLE:
|
| 723 | case AUDIT_SUBJ_TYPE:
|
| 724 | case AUDIT_SUBJ_SEN:
|
| 725 | case AUDIT_SUBJ_CLR:
|
| 726 | case AUDIT_OBJ_USER:
|
| 727 | case AUDIT_OBJ_ROLE:
|
| 728 | case AUDIT_OBJ_TYPE:
|
| 729 | case AUDIT_OBJ_LEV_LOW:
|
| 730 | case AUDIT_OBJ_LEV_HIGH:
|
| 731 | if (strcmp(a->fields[i].lsm_str, b->fields[i].lsm_str))
|
| 732 | return 1;
|
| 733 | break;
|
| 734 | case AUDIT_WATCH:
|
| 735 | if (strcmp(audit_watch_path(a->watch),
|
| 736 | audit_watch_path(b->watch)))
|
| 737 | return 1;
|
| 738 | break;
|
| 739 | case AUDIT_DIR:
|
| 740 | if (strcmp(audit_tree_path(a->tree),
|
| 741 | audit_tree_path(b->tree)))
|
| 742 | return 1;
|
| 743 | break;
|
| 744 | case AUDIT_FILTERKEY:
|
| 745 |
|
| 746 | if (strcmp(a->filterkey, b->filterkey))
|
| 747 | return 1;
|
| 748 | break;
|
| 749 | case AUDIT_EXE:
|
| 750 |
|
| 751 | if (strcmp(audit_mark_path(a->exe),
|
| 752 | audit_mark_path(b->exe)))
|
| 753 | return 1;
|
| 754 | break;
|
| 755 | case AUDIT_UID:
|
| 756 | case AUDIT_EUID:
|
| 757 | case AUDIT_SUID:
|
| 758 | case AUDIT_FSUID:
|
| 759 | case AUDIT_LOGINUID:
|
| 760 | case AUDIT_OBJ_UID:
|
| 761 | if (!uid_eq(a->fields[i].uid, b->fields[i].uid))
|
| 762 | return 1;
|
| 763 | break;
|
| 764 | case AUDIT_GID:
|
| 765 | case AUDIT_EGID:
|
| 766 | case AUDIT_SGID:
|
| 767 | case AUDIT_FSGID:
|
| 768 | case AUDIT_OBJ_GID:
|
| 769 | if (!gid_eq(a->fields[i].gid, b->fields[i].gid))
|
| 770 | return 1;
|
| 771 | break;
|
| 772 | default:
|
| 773 | if (a->fields[i].val != b->fields[i].val)
|
| 774 | return 1;
|
| 775 | }
|
| 776 | }
|
| 777 |
|
| 778 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
|
| 779 | if (a->mask[i] != b->mask[i])
|
| 780 | return 1;
|
| 781 |
|
| 782 | return 0;
|
| 783 | }
|
| 784 |
|
| 785 | |
| 786 | * re-initialized.
|
| 787 | static inline int audit_dupe_lsm_field(struct audit_field *df,
|
| 788 | struct audit_field *sf)
|
| 789 | {
|
| 790 | int ret;
|
| 791 | char *lsm_str;
|
| 792 |
|
| 793 |
|
| 794 | lsm_str = kstrdup(sf->lsm_str, GFP_KERNEL);
|
| 795 | if (unlikely(!lsm_str))
|
| 796 | return -ENOMEM;
|
| 797 | df->lsm_str = lsm_str;
|
| 798 |
|
| 799 |
|
| 800 | ret = security_audit_rule_init(df->type, df->op, df->lsm_str,
|
| 801 | (void **)&df->lsm_rule, GFP_KERNEL);
|
| 802 | |
| 803 | * become valid after a policy reload.
|
| 804 | if (ret == -EINVAL) {
|
| 805 | pr_warn("audit rule for LSM \'%s\' is invalid\n",
|
| 806 | df->lsm_str);
|
| 807 | ret = 0;
|
| 808 | }
|
| 809 |
|
| 810 | return ret;
|
| 811 | }
|
| 812 |
|
| 813 | |
| 814 | * of the watch - that pointer is carried over. The LSM specific fields
|
| 815 | * will be updated in the copy. The point is to be able to replace the old
|
| 816 | * rule with the new rule in the filterlist, then free the old rule.
|
| 817 | * The rlist element is undefined; list manipulations are handled apart from
|
| 818 | * the initial copy.
|
| 819 | struct audit_entry *audit_dupe_rule(struct audit_krule *old,
|
| 820 | struct audit_watch_ctx *ctx)
|
| 821 | {
|
| 822 | u32 fcount = old->field_count;
|
| 823 | struct audit_entry *entry;
|
| 824 | struct audit_krule *new;
|
| 825 | char *fk;
|
| 826 | int i, err = 0;
|
| 827 |
|
| 828 | entry = audit_init_entry(fcount);
|
| 829 | if (unlikely(!entry))
|
| 830 | return ERR_PTR(-ENOMEM);
|
| 831 |
|
| 832 | new = &entry->rule;
|
| 833 | new->flags = old->flags;
|
| 834 | new->pflags = old->pflags;
|
| 835 | new->listnr = old->listnr;
|
| 836 | new->action = old->action;
|
| 837 | for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
|
| 838 | new->mask[i] = old->mask[i];
|
| 839 | new->prio = old->prio;
|
| 840 | new->buflen = old->buflen;
|
| 841 | new->inode_f = old->inode_f;
|
| 842 | new->field_count = old->field_count;
|
| 843 |
|
| 844 | |
| 845 | * note that we are OK with not refcounting here; audit_match_tree()
|
| 846 | * never dereferences tree and we can't get false positives there
|
| 847 | * since we'd have to have rule gone from the list *and* removed
|
| 848 | * before the chunks found by lookup had been allocated, i.e. before
|
| 849 | * the beginning of list scan.
|
| 850 |
|
| 851 | new->tree = old->tree;
|
| 852 | memcpy(new->fields, old->fields, sizeof(struct audit_field) * fcount);
|
| 853 |
|
| 854 | |
| 855 | * the originals will all be freed when the old rule is freed.
|
| 856 | for (i = 0; i < fcount; i++) {
|
| 857 | switch (new->fields[i].type) {
|
| 858 | case AUDIT_SUBJ_USER:
|
| 859 | case AUDIT_SUBJ_ROLE:
|
| 860 | case AUDIT_SUBJ_TYPE:
|
| 861 | case AUDIT_SUBJ_SEN:
|
| 862 | case AUDIT_SUBJ_CLR:
|
| 863 | case AUDIT_OBJ_USER:
|
| 864 | case AUDIT_OBJ_ROLE:
|
| 865 | case AUDIT_OBJ_TYPE:
|
| 866 | case AUDIT_OBJ_LEV_LOW:
|
| 867 | case AUDIT_OBJ_LEV_HIGH:
|
| 868 | err = audit_dupe_lsm_field(&new->fields[i],
|
| 869 | &old->fields[i]);
|
| 870 | break;
|
| 871 | case AUDIT_FILTERKEY:
|
| 872 | fk = kstrdup(old->filterkey, GFP_KERNEL);
|
| 873 | if (unlikely(!fk))
|
| 874 | err = -ENOMEM;
|
| 875 | else
|
| 876 | new->filterkey = fk;
|
| 877 | break;
|
| 878 | case AUDIT_EXE:
|
| 879 | err = audit_dupe_exe(new, old, ctx);
|
| 880 | break;
|
| 881 | }
|
| 882 | if (err) {
|
| 883 | if (new->exe)
|
| 884 | audit_remove_mark(new->exe);
|
| 885 | audit_free_rule(entry);
|
| 886 | return ERR_PTR(err);
|
| 887 | }
|
| 888 | }
|
| 889 |
|
| 890 | if (old->watch) {
|
| 891 | audit_get_watch(old->watch);
|
| 892 | new->watch = old->watch;
|
| 893 | }
|
| 894 |
|
| 895 | return entry;
|
| 896 | }
|
| 897 |
|
| 898 | |
| 899 | * Caller must hold audit_filter_mutex to prevent stale rule data.
|
| 900 | static struct audit_entry *audit_find_rule(struct audit_entry *entry,
|
| 901 | struct list_head **p)
|
| 902 | {
|
| 903 | struct audit_entry *e, *found = NULL;
|
| 904 | struct list_head *list;
|
| 905 | int h;
|
| 906 |
|
| 907 | if (entry->rule.inode_f) {
|
| 908 | h = audit_hash_ino(entry->rule.inode_f->val);
|
| 909 | *p = list = &audit_inode_hash[h];
|
| 910 | } else if (entry->rule.watch) {
|
| 911 |
|
| 912 | for (h = 0; h < AUDIT_INODE_BUCKETS; h++) {
|
| 913 | list = &audit_inode_hash[h];
|
| 914 | list_for_each_entry(e, list, list)
|
| 915 | if (!audit_compare_rule(&entry->rule, &e->rule)) {
|
| 916 | found = e;
|
| 917 | goto out;
|
| 918 | }
|
| 919 | }
|
| 920 | goto out;
|
| 921 | } else {
|
| 922 | *p = list = &audit_filter_list[entry->rule.listnr];
|
| 923 | }
|
| 924 |
|
| 925 | list_for_each_entry(e, list, list)
|
| 926 | if (!audit_compare_rule(&entry->rule, &e->rule)) {
|
| 927 | found = e;
|
| 928 | goto out;
|
| 929 | }
|
| 930 |
|
| 931 | out:
|
| 932 | return found;
|
| 933 | }
|
| 934 |
|
| 935 | static u64 prio_low = ~0ULL/2;
|
| 936 | static u64 prio_high = ~0ULL/2 - 1;
|
| 937 |
|
| 938 |
|
| 939 | static inline int audit_add_rule(struct audit_entry *entry)
|
| 940 | {
|
| 941 | struct audit_entry *e;
|
| 942 | struct audit_watch *watch = entry->rule.watch;
|
| 943 | struct audit_tree *tree = entry->rule.tree;
|
| 944 | struct list_head *list;
|
| 945 | int err = 0;
|
| 946 | #ifdef CONFIG_AUDITSYSCALL
|
| 947 | int dont_count = 0;
|
| 948 |
|
| 949 |
|
| 950 | switch (entry->rule.listnr) {
|
| 951 | case AUDIT_FILTER_USER:
|
| 952 | case AUDIT_FILTER_EXCLUDE:
|
| 953 | case AUDIT_FILTER_FS:
|
| 954 | dont_count = 1;
|
| 955 | }
|
| 956 | #endif
|
| 957 |
|
| 958 | mutex_lock(&audit_filter_mutex);
|
| 959 | e = audit_find_rule(entry, &list);
|
| 960 | if (e) {
|
| 961 | mutex_unlock(&audit_filter_mutex);
|
| 962 | err = -EEXIST;
|
| 963 |
|
| 964 | if (tree)
|
| 965 | audit_put_tree(tree);
|
| 966 | return err;
|
| 967 | }
|
| 968 |
|
| 969 | if (watch) {
|
| 970 |
|
| 971 | err = audit_add_watch(&entry->rule, &list);
|
| 972 | if (err) {
|
| 973 | mutex_unlock(&audit_filter_mutex);
|
| 974 | |
| 975 | * normally audit_add_tree_rule() will free it
|
| 976 | * on failure
|
| 977 |
|
| 978 | if (tree)
|
| 979 | audit_put_tree(tree);
|
| 980 | return err;
|
| 981 | }
|
| 982 | }
|
| 983 | if (tree) {
|
| 984 | err = audit_add_tree_rule(&entry->rule);
|
| 985 | if (err) {
|
| 986 | mutex_unlock(&audit_filter_mutex);
|
| 987 | return err;
|
| 988 | }
|
| 989 | }
|
| 990 |
|
| 991 | entry->rule.prio = ~0ULL;
|
| 992 | if (entry->rule.listnr == AUDIT_FILTER_EXIT ||
|
| 993 | entry->rule.listnr == AUDIT_FILTER_URING_EXIT) {
|
| 994 | if (entry->rule.flags & AUDIT_FILTER_PREPEND)
|
| 995 | entry->rule.prio = ++prio_high;
|
| 996 | else
|
| 997 | entry->rule.prio = --prio_low;
|
| 998 | }
|
| 999 |
|
| 1000 | if (entry->rule.flags & AUDIT_FILTER_PREPEND) {
|
| 1001 | list_add(&entry->rule.list,
|
| 1002 | &audit_rules_list[entry->rule.listnr]);
|
| 1003 | list_add_rcu(&entry->list, list);
|
| 1004 | entry->rule.flags &= ~AUDIT_FILTER_PREPEND;
|
| 1005 | } else {
|
| 1006 | list_add_tail(&entry->rule.list,
|
| 1007 | &audit_rules_list[entry->rule.listnr]);
|
| 1008 | list_add_tail_rcu(&entry->list, list);
|
| 1009 | }
|
| 1010 | #ifdef CONFIG_AUDITSYSCALL
|
| 1011 | if (!dont_count)
|
| 1012 | audit_n_rules++;
|
| 1013 |
|
| 1014 | if (!audit_match_signal(entry))
|
| 1015 | audit_signals++;
|
| 1016 | #endif
|
| 1017 | mutex_unlock(&audit_filter_mutex);
|
| 1018 |
|
| 1019 | return err;
|
| 1020 | }
|
| 1021 |
|
| 1022 |
|
| 1023 | int audit_del_rule(struct audit_entry *entry)
|
| 1024 | {
|
| 1025 | struct audit_entry *e;
|
| 1026 | struct list_head *list;
|
| 1027 | int ret = 0;
|
| 1028 | #ifdef CONFIG_AUDITSYSCALL
|
| 1029 | int dont_count = 0;
|
| 1030 |
|
| 1031 |
|
| 1032 | switch (entry->rule.listnr) {
|
| 1033 | case AUDIT_FILTER_USER:
|
| 1034 | case AUDIT_FILTER_EXCLUDE:
|
| 1035 | case AUDIT_FILTER_FS:
|
| 1036 | dont_count = 1;
|
| 1037 | }
|
| 1038 | #endif
|
| 1039 |
|
| 1040 | mutex_lock(&audit_filter_mutex);
|
| 1041 | e = audit_find_rule(entry, &list);
|
| 1042 | if (!e) {
|
| 1043 | ret = -ENOENT;
|
| 1044 | goto out;
|
| 1045 | }
|
| 1046 |
|
| 1047 | list_del_rcu(&e->list);
|
| 1048 | list_del(&e->rule.list);
|
| 1049 | synchronize_rcu();
|
| 1050 |
|
| 1051 | if (e->rule.watch)
|
| 1052 | audit_remove_watch_rule(&e->rule);
|
| 1053 |
|
| 1054 | if (e->rule.tree)
|
| 1055 | audit_remove_tree_rule(&e->rule);
|
| 1056 |
|
| 1057 | if (e->rule.exe)
|
| 1058 | audit_remove_mark_rule(&e->rule);
|
| 1059 |
|
| 1060 | #ifdef CONFIG_AUDITSYSCALL
|
| 1061 | if (!dont_count)
|
| 1062 | audit_n_rules--;
|
| 1063 |
|
| 1064 | if (!audit_match_signal(entry))
|
| 1065 | audit_signals--;
|
| 1066 | #endif
|
| 1067 |
|
| 1068 | call_rcu(&e->rcu, audit_free_rule_rcu);
|
| 1069 |
|
| 1070 | out:
|
| 1071 | mutex_unlock(&audit_filter_mutex);
|
| 1072 |
|
| 1073 | return ret;
|
| 1074 | }
|
| 1075 |
|
| 1076 |
|
| 1077 | static void audit_list_rules(int seq, struct sk_buff_head *q)
|
| 1078 | {
|
| 1079 | struct sk_buff *skb;
|
| 1080 | struct audit_krule *r;
|
| 1081 | int i;
|
| 1082 |
|
| 1083 | |
| 1084 | * iterator to sync with list writers.
|
| 1085 | for (i = 0; i < AUDIT_NR_FILTERS; i++) {
|
| 1086 | list_for_each_entry(r, &audit_rules_list[i], list) {
|
| 1087 | struct audit_rule_data *data;
|
| 1088 |
|
| 1089 | data = audit_krule_to_data(r);
|
| 1090 | if (unlikely(!data))
|
| 1091 | break;
|
| 1092 | skb = audit_make_reply(seq, AUDIT_LIST_RULES, 0, 1,
|
| 1093 | data,
|
| 1094 | struct_size(data, buf, data->buflen));
|
| 1095 | if (skb)
|
| 1096 | skb_queue_tail(q, skb);
|
| 1097 | kfree(data);
|
| 1098 | }
|
| 1099 | }
|
| 1100 | skb = audit_make_reply(seq, AUDIT_LIST_RULES, 1, 1, NULL, 0);
|
| 1101 | if (skb)
|
| 1102 | skb_queue_tail(q, skb);
|
| 1103 | }
|
| 1104 |
|
| 1105 |
|
| 1106 | static void audit_log_rule_change(char *action, struct audit_krule *rule, int res)
|
| 1107 | {
|
| 1108 | struct audit_buffer *ab;
|
| 1109 |
|
| 1110 | if (!audit_enabled)
|
| 1111 | return;
|
| 1112 |
|
| 1113 | ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_CONFIG_CHANGE);
|
| 1114 | if (!ab)
|
| 1115 | return;
|
| 1116 | audit_log_session_info(ab);
|
| 1117 | audit_log_task_context(ab);
|
| 1118 | audit_log_format(ab, " op=%s", action);
|
| 1119 | audit_log_key(ab, rule->filterkey);
|
| 1120 | audit_log_format(ab, " list=%d res=%d", rule->listnr, res);
|
| 1121 | audit_log_end(ab);
|
| 1122 | }
|
| 1123 |
|
| 1124 | |
| 1125 | * audit_rule_change - apply all rules to the specified message type
|
| 1126 | * @type: audit message type
|
| 1127 | * @seq: netlink audit message sequence (serial) number
|
| 1128 | * @data: payload data
|
| 1129 | * @datasz: size of payload data
|
| 1130 |
|
| 1131 | int audit_rule_change(int type, int seq, void *data, size_t datasz)
|
| 1132 | {
|
| 1133 | int err = 0;
|
| 1134 | struct audit_entry *entry;
|
| 1135 |
|
| 1136 | switch (type) {
|
| 1137 | case AUDIT_ADD_RULE:
|
| 1138 | entry = audit_data_to_entry(data, datasz);
|
| 1139 | if (IS_ERR(entry))
|
| 1140 | return PTR_ERR(entry);
|
| 1141 | err = audit_add_rule(entry);
|
| 1142 | audit_log_rule_change("add_rule", &entry->rule, !err);
|
| 1143 | break;
|
| 1144 | case AUDIT_DEL_RULE:
|
| 1145 | entry = audit_data_to_entry(data, datasz);
|
| 1146 | if (IS_ERR(entry))
|
| 1147 | return PTR_ERR(entry);
|
| 1148 | err = audit_del_rule(entry);
|
| 1149 | audit_log_rule_change("remove_rule", &entry->rule, !err);
|
| 1150 | break;
|
| 1151 | default:
|
| 1152 | WARN_ON(1);
|
| 1153 | return -EINVAL;
|
| 1154 | }
|
| 1155 |
|
| 1156 | if (err || type == AUDIT_DEL_RULE) {
|
| 1157 | if (type == AUDIT_DEL_RULE && entry->rule.tree)
|
| 1158 | audit_put_tree(entry->rule.tree);
|
| 1159 | if (entry->rule.exe)
|
| 1160 | audit_remove_mark(entry->rule.exe);
|
| 1161 | audit_free_rule(entry);
|
| 1162 | }
|
| 1163 |
|
| 1164 | return err;
|
| 1165 | }
|
| 1166 |
|
| 1167 | |
| 1168 | * audit_list_rules_send - list the audit rules
|
| 1169 | * @request_skb: skb of request we are replying to (used to target the reply)
|
| 1170 | * @seq: netlink audit message sequence (serial) number
|
| 1171 |
|
| 1172 | int audit_list_rules_send(struct sk_buff *request_skb, int seq)
|
| 1173 | {
|
| 1174 | struct task_struct *tsk;
|
| 1175 | struct audit_netlink_list *dest;
|
| 1176 |
|
| 1177 | |
| 1178 | * the available socket buffer space and deadlock waiting for
|
| 1179 | * auditctl to read from it... which isn't ever going to
|
| 1180 | * happen if we're actually running in the context of auditctl
|
| 1181 | * trying to _send_ the stuff
|
| 1182 |
|
| 1183 | dest = kmalloc_obj(*dest);
|
| 1184 | if (!dest)
|
| 1185 | return -ENOMEM;
|
| 1186 | dest->net = get_net(sock_net(NETLINK_CB(request_skb).sk));
|
| 1187 | dest->portid = NETLINK_CB(request_skb).portid;
|
| 1188 | skb_queue_head_init(&dest->q);
|
| 1189 |
|
| 1190 | mutex_lock(&audit_filter_mutex);
|
| 1191 | audit_list_rules(seq, &dest->q);
|
| 1192 | mutex_unlock(&audit_filter_mutex);
|
| 1193 |
|
| 1194 | tsk = kthread_run(audit_send_list_thread, dest, "audit_send_list");
|
| 1195 | if (IS_ERR(tsk)) {
|
| 1196 | skb_queue_purge(&dest->q);
|
| 1197 | put_net(dest->net);
|
| 1198 | kfree(dest);
|
| 1199 | return PTR_ERR(tsk);
|
| 1200 | }
|
| 1201 |
|
| 1202 | return 0;
|
| 1203 | }
|
| 1204 |
|
| 1205 | int audit_comparator(u32 left, u32 op, u32 right)
|
| 1206 | {
|
| 1207 | switch (op) {
|
| 1208 | case Audit_equal:
|
| 1209 | return (left == right);
|
| 1210 | case Audit_not_equal:
|
| 1211 | return (left != right);
|
| 1212 | case Audit_lt:
|
| 1213 | return (left < right);
|
| 1214 | case Audit_le:
|
| 1215 | return (left <= right);
|
| 1216 | case Audit_gt:
|
| 1217 | return (left > right);
|
| 1218 | case Audit_ge:
|
| 1219 | return (left >= right);
|
| 1220 | case Audit_bitmask:
|
| 1221 | return (left & right);
|
| 1222 | case Audit_bittest:
|
| 1223 | return ((left & right) == right);
|
| 1224 | default:
|
| 1225 | return 0;
|
| 1226 | }
|
| 1227 | }
|
| 1228 |
|
| 1229 | int audit_uid_comparator(kuid_t left, u32 op, kuid_t right)
|
| 1230 | {
|
| 1231 | switch (op) {
|
| 1232 | case Audit_equal:
|
| 1233 | return uid_eq(left, right);
|
| 1234 | case Audit_not_equal:
|
| 1235 | return !uid_eq(left, right);
|
| 1236 | case Audit_lt:
|
| 1237 | return uid_lt(left, right);
|
| 1238 | case Audit_le:
|
| 1239 | return uid_lte(left, right);
|
| 1240 | case Audit_gt:
|
| 1241 | return uid_gt(left, right);
|
| 1242 | case Audit_ge:
|
| 1243 | return uid_gte(left, right);
|
| 1244 | case Audit_bitmask:
|
| 1245 | case Audit_bittest:
|
| 1246 | default:
|
| 1247 | return 0;
|
| 1248 | }
|
| 1249 | }
|
| 1250 |
|
| 1251 | int audit_gid_comparator(kgid_t left, u32 op, kgid_t right)
|
| 1252 | {
|
| 1253 | switch (op) {
|
| 1254 | case Audit_equal:
|
| 1255 | return gid_eq(left, right);
|
| 1256 | case Audit_not_equal:
|
| 1257 | return !gid_eq(left, right);
|
| 1258 | case Audit_lt:
|
| 1259 | return gid_lt(left, right);
|
| 1260 | case Audit_le:
|
| 1261 | return gid_lte(left, right);
|
| 1262 | case Audit_gt:
|
| 1263 | return gid_gt(left, right);
|
| 1264 | case Audit_ge:
|
| 1265 | return gid_gte(left, right);
|
| 1266 | case Audit_bitmask:
|
| 1267 | case Audit_bittest:
|
| 1268 | default:
|
| 1269 | return 0;
|
| 1270 | }
|
| 1271 | }
|
| 1272 |
|
| 1273 | |
| 1274 | * parent_len - find the length of the parent portion of a pathname
|
| 1275 | * @path: pathname of which to determine length
|
| 1276 |
|
| 1277 | int parent_len(const char *path)
|
| 1278 | {
|
| 1279 | int plen;
|
| 1280 | const char *p;
|
| 1281 |
|
| 1282 | plen = strlen(path);
|
| 1283 |
|
| 1284 | if (plen == 0)
|
| 1285 | return plen;
|
| 1286 |
|
| 1287 |
|
| 1288 | p = path + plen - 1;
|
| 1289 | while ((*p == '/') && (p > path))
|
| 1290 | p--;
|
| 1291 |
|
| 1292 |
|
| 1293 | while ((*p != '/') && (p > path))
|
| 1294 | p--;
|
| 1295 |
|
| 1296 |
|
| 1297 | if (*p == '/')
|
| 1298 | p++;
|
| 1299 |
|
| 1300 | return p - path;
|
| 1301 | }
|
| 1302 |
|
| 1303 | |
| 1304 | * audit_compare_dname_path - compare given dentry name with last component in
|
| 1305 | * given path. Return of 0 indicates a match.
|
| 1306 | * @dname: dentry name that we're comparing
|
| 1307 | * @path: full pathname that we're comparing
|
| 1308 | * @parentlen: length of the parent if known. Passing in AUDIT_NAME_FULL
|
| 1309 | * here indicates that we must compute this value.
|
| 1310 |
|
| 1311 | int audit_compare_dname_path(const struct qstr *dname, const char *path, int parentlen)
|
| 1312 | {
|
| 1313 | int dlen, pathlen;
|
| 1314 | const char *p;
|
| 1315 |
|
| 1316 | dlen = dname->len;
|
| 1317 | pathlen = strlen(path);
|
| 1318 | if (pathlen < dlen)
|
| 1319 | return 1;
|
| 1320 |
|
| 1321 | if (parentlen == AUDIT_NAME_FULL)
|
| 1322 | parentlen = parent_len(path);
|
| 1323 |
|
| 1324 | p = path + parentlen;
|
| 1325 |
|
| 1326 |
|
| 1327 | pathlen -= parentlen;
|
| 1328 | while (pathlen > 0 && p[pathlen - 1] == '/')
|
| 1329 | pathlen--;
|
| 1330 |
|
| 1331 | if (pathlen != dlen)
|
| 1332 | return 1;
|
| 1333 |
|
| 1334 | return memcmp(p, dname->name, dlen);
|
| 1335 | }
|
| 1336 |
|
| 1337 | int audit_filter(int msgtype, unsigned int listtype)
|
| 1338 | {
|
| 1339 | struct audit_entry *e;
|
| 1340 | int ret = 1;
|
| 1341 |
|
| 1342 | rcu_read_lock();
|
| 1343 | list_for_each_entry_rcu(e, &audit_filter_list[listtype], list) {
|
| 1344 | int i, result = 0;
|
| 1345 |
|
| 1346 | for (i = 0; i < e->rule.field_count; i++) {
|
| 1347 | struct audit_field *f = &e->rule.fields[i];
|
| 1348 | struct lsm_prop prop = { };
|
| 1349 | pid_t pid;
|
| 1350 |
|
| 1351 | switch (f->type) {
|
| 1352 | case AUDIT_PID:
|
| 1353 | pid = task_tgid_nr(current);
|
| 1354 | result = audit_comparator(pid, f->op, f->val);
|
| 1355 | break;
|
| 1356 | case AUDIT_UID:
|
| 1357 | result = audit_uid_comparator(current_uid(), f->op, f->uid);
|
| 1358 | break;
|
| 1359 | case AUDIT_GID:
|
| 1360 | result = audit_gid_comparator(current_gid(), f->op, f->gid);
|
| 1361 | break;
|
| 1362 | case AUDIT_LOGINUID:
|
| 1363 | result = audit_uid_comparator(audit_get_loginuid(current),
|
| 1364 | f->op, f->uid);
|
| 1365 | break;
|
| 1366 | case AUDIT_LOGINUID_SET:
|
| 1367 | result = audit_comparator(audit_loginuid_set(current),
|
| 1368 | f->op, f->val);
|
| 1369 | break;
|
| 1370 | case AUDIT_MSGTYPE:
|
| 1371 | result = audit_comparator(msgtype, f->op, f->val);
|
| 1372 | break;
|
| 1373 | case AUDIT_SUBJ_USER:
|
| 1374 | case AUDIT_SUBJ_ROLE:
|
| 1375 | case AUDIT_SUBJ_TYPE:
|
| 1376 | case AUDIT_SUBJ_SEN:
|
| 1377 | case AUDIT_SUBJ_CLR:
|
| 1378 | if (f->lsm_rule) {
|
| 1379 | security_current_getlsmprop_subj(&prop);
|
| 1380 | result = security_audit_rule_match(
|
| 1381 | &prop, f->type, f->op,
|
| 1382 | f->lsm_rule);
|
| 1383 | }
|
| 1384 | break;
|
| 1385 | case AUDIT_EXE:
|
| 1386 | result = audit_exe_compare(current, e->rule.exe);
|
| 1387 | if (f->op == Audit_not_equal)
|
| 1388 | result = !result;
|
| 1389 | break;
|
| 1390 | default:
|
| 1391 | goto unlock_and_return;
|
| 1392 | }
|
| 1393 | if (result < 0)
|
| 1394 | goto unlock_and_return;
|
| 1395 | if (!result)
|
| 1396 | break;
|
| 1397 | }
|
| 1398 | if (result > 0) {
|
| 1399 | if (e->rule.action == AUDIT_NEVER || listtype == AUDIT_FILTER_EXCLUDE)
|
| 1400 | ret = 0;
|
| 1401 | break;
|
| 1402 | }
|
| 1403 | }
|
| 1404 | unlock_and_return:
|
| 1405 | rcu_read_unlock();
|
| 1406 | return ret;
|
| 1407 | }
|
| 1408 |
|
| 1409 | static int update_lsm_rule(struct audit_krule *r)
|
| 1410 | {
|
| 1411 | struct audit_entry *entry = container_of(r, struct audit_entry, rule);
|
| 1412 | struct audit_entry *nentry;
|
| 1413 | int err = 0;
|
| 1414 |
|
| 1415 | if (!security_audit_rule_known(r))
|
| 1416 | return 0;
|
| 1417 |
|
| 1418 | nentry = audit_dupe_rule(r, NULL);
|
| 1419 | if (entry->rule.exe)
|
| 1420 | audit_remove_mark(entry->rule.exe);
|
| 1421 | if (IS_ERR(nentry)) {
|
| 1422 | |
| 1423 | * return value
|
| 1424 | err = PTR_ERR(nentry);
|
| 1425 | audit_panic("error updating LSM filters");
|
| 1426 | if (r->watch)
|
| 1427 | list_del(&r->rlist);
|
| 1428 | list_del_rcu(&entry->list);
|
| 1429 | list_del(&r->list);
|
| 1430 | } else {
|
| 1431 | if (r->watch || r->tree)
|
| 1432 | list_replace_init(&r->rlist, &nentry->rule.rlist);
|
| 1433 | list_replace_rcu(&entry->list, &nentry->list);
|
| 1434 | list_replace(&r->list, &nentry->rule.list);
|
| 1435 | }
|
| 1436 | call_rcu(&entry->rcu, audit_free_rule_rcu);
|
| 1437 |
|
| 1438 | return err;
|
| 1439 | }
|
| 1440 |
|
| 1441 | |
| 1442 | * It will traverse the filter lists searching for rules that contain LSM
|
| 1443 | * specific filter fields. When such a rule is found, it is copied, the
|
| 1444 | * LSM field is re-initialized, and the old rule is replaced with the
|
| 1445 | * updated rule.
|
| 1446 | int audit_update_lsm_rules(void)
|
| 1447 | {
|
| 1448 | struct audit_krule *r, *n;
|
| 1449 | int i, err = 0;
|
| 1450 |
|
| 1451 |
|
| 1452 | mutex_lock(&audit_filter_mutex);
|
| 1453 |
|
| 1454 | for (i = 0; i < AUDIT_NR_FILTERS; i++) {
|
| 1455 | list_for_each_entry_safe(r, n, &audit_rules_list[i], list) {
|
| 1456 | int res = update_lsm_rule(r);
|
| 1457 | if (!err)
|
| 1458 | err = res;
|
| 1459 | }
|
| 1460 | }
|
| 1461 | mutex_unlock(&audit_filter_mutex);
|
| 1462 |
|
| 1463 | return err;
|
| 1464 | }
|