1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Security plug functions 4 * 5 * Copyright (C) 2001 WireX Communications, Inc <chris@wirex.com> 6 * Copyright (C) 2001-2002 Greg Kroah-Hartman <greg@kroah.com> 7 * Copyright (C) 2001 Networks Associates Technology, Inc <ssmalley@nai.com> 8 * Copyright (C) 2016 Mellanox Technologies 9 * Copyright (C) 2023 Microsoft Corporation <paul@paul-moore.com> 10 */ 11 12 #define pr_fmt(fmt) "LSM: " fmt 13 14 #include <linux/bpf.h> 15 #include <linux/capability.h> 16 #include <linux/dcache.h> 17 #include <linux/export.h> 18 #include <linux/init.h> 19 #include <linux/kernel.h> 20 #include <linux/kernel_read_file.h> 21 #include <linux/lsm_hooks.h> 22 #include <linux/mman.h> 23 #include <linux/mount.h> 24 #include <linux/personality.h> 25 #include <linux/backing-dev.h> 26 #include <linux/string.h> 27 #include <linux/xattr.h> 28 #include <linux/msg.h> 29 #include <linux/overflow.h> 30 #include <linux/perf_event.h> 31 #include <linux/fs.h> 32 #include <net/flow.h> 33 #include <net/sock.h> 34 35 #include "lsm.h" 36 37 /* 38 * These are descriptions of the reasons that can be passed to the 39 * security_locked_down() LSM hook. Placing this array here allows 40 * all security modules to use the same descriptions for auditing 41 * purposes. 42 */ 43 const char *const lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX + 1] = { 44 [LOCKDOWN_NONE] = "none", 45 [LOCKDOWN_MODULE_SIGNATURE] = "unsigned module loading", 46 [LOCKDOWN_DEV_MEM] = "/dev/mem,kmem,port", 47 [LOCKDOWN_EFI_TEST] = "/dev/efi_test access", 48 [LOCKDOWN_KEXEC] = "kexec of unsigned images", 49 [LOCKDOWN_HIBERNATION] = "hibernation", 50 [LOCKDOWN_PCI_ACCESS] = "direct PCI access", 51 [LOCKDOWN_IOPORT] = "raw io port access", 52 [LOCKDOWN_MSR] = "raw MSR access", 53 [LOCKDOWN_ACPI_TABLES] = "modifying ACPI tables", 54 [LOCKDOWN_DEVICE_TREE] = "modifying device tree contents", 55 [LOCKDOWN_PCMCIA_CIS] = "direct PCMCIA CIS storage", 56 [LOCKDOWN_TIOCSSERIAL] = "reconfiguration of serial port IO", 57 [LOCKDOWN_MODULE_PARAMETERS] = "unsafe module parameters", 58 [LOCKDOWN_MMIOTRACE] = "unsafe mmio", 59 [LOCKDOWN_DEBUGFS] = "debugfs access", 60 [LOCKDOWN_XMON_WR] = "xmon write access", 61 [LOCKDOWN_BPF_WRITE_USER] = "use of bpf to write user RAM", 62 [LOCKDOWN_DBG_WRITE_KERNEL] = "use of kgdb/kdb to write kernel RAM", 63 [LOCKDOWN_RTAS_ERROR_INJECTION] = "RTAS error injection", 64 [LOCKDOWN_XEN_USER_ACTIONS] = "Xen guest user action", 65 [LOCKDOWN_INTEGRITY_MAX] = "integrity", 66 [LOCKDOWN_KCORE] = "/proc/kcore access", 67 [LOCKDOWN_KPROBES] = "use of kprobes", 68 [LOCKDOWN_BPF_READ_KERNEL] = "use of bpf to read kernel RAM", 69 [LOCKDOWN_DBG_READ_KERNEL] = "use of kgdb/kdb to read kernel RAM", 70 [LOCKDOWN_PERF] = "unsafe use of perf", 71 [LOCKDOWN_TRACEFS] = "use of tracefs", 72 [LOCKDOWN_XMON_RW] = "xmon read and write access", 73 [LOCKDOWN_XFRM_SECRET] = "xfrm SA secret", 74 [LOCKDOWN_CONFIDENTIALITY_MAX] = "confidentiality", 75 }; 76 77 bool lsm_debug __ro_after_init; 78 79 unsigned int lsm_active_cnt __ro_after_init; 80 const struct lsm_id *lsm_idlist[MAX_LSM_COUNT]; 81 82 struct lsm_blob_sizes blob_sizes; 83 84 struct kmem_cache *lsm_file_cache; 85 struct kmem_cache *lsm_backing_file_cache; 86 struct kmem_cache *lsm_inode_cache; 87 88 #define SECURITY_HOOK_ACTIVE_KEY(HOOK, IDX) security_hook_active_##HOOK##_##IDX 89 90 /* 91 * Identifier for the LSM static calls. 92 * HOOK is an LSM hook as defined in linux/lsm_hookdefs.h 93 * IDX is the index of the static call. 0 <= NUM < MAX_LSM_COUNT 94 */ 95 #define LSM_STATIC_CALL(HOOK, IDX) lsm_static_call_##HOOK##_##IDX 96 97 /* 98 * Call the macro M for each LSM hook MAX_LSM_COUNT times. 99 */ 100 #define LSM_LOOP_UNROLL(M, ...) \ 101 do { \ 102 UNROLL(MAX_LSM_COUNT, M, __VA_ARGS__) \ 103 } while (0) 104 105 #define LSM_DEFINE_UNROLL(M, ...) UNROLL(MAX_LSM_COUNT, M, __VA_ARGS__) 106 107 #ifdef CONFIG_HAVE_STATIC_CALL 108 #define LSM_HOOK_TRAMP(NAME, NUM) \ 109 &STATIC_CALL_TRAMP(LSM_STATIC_CALL(NAME, NUM)) 110 #else 111 #define LSM_HOOK_TRAMP(NAME, NUM) NULL 112 #endif 113 114 /* 115 * Define static calls and static keys for each LSM hook. 116 */ 117 #define DEFINE_LSM_STATIC_CALL(NUM, NAME, RET, ...) \ 118 DEFINE_STATIC_CALL_NULL(LSM_STATIC_CALL(NAME, NUM), \ 119 *((RET(*)(__VA_ARGS__))NULL)); \ 120 static DEFINE_STATIC_KEY_FALSE(SECURITY_HOOK_ACTIVE_KEY(NAME, NUM)); 121 122 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \ 123 LSM_DEFINE_UNROLL(DEFINE_LSM_STATIC_CALL, NAME, RET, __VA_ARGS__) 124 #include <linux/lsm_hook_defs.h> 125 #undef LSM_HOOK 126 #undef DEFINE_LSM_STATIC_CALL 127 128 /* 129 * Initialise a table of static calls for each LSM hook. 130 * DEFINE_STATIC_CALL_NULL invocation above generates a key (STATIC_CALL_KEY) 131 * and a trampoline (STATIC_CALL_TRAMP) which are used to call 132 * __static_call_update when updating the static call. 133 * 134 * The static calls table is used by early LSMs, some architectures can fault on 135 * unaligned accesses and the fault handling code may not be ready by then. 136 * Thus, the static calls table should be aligned to avoid any unhandled faults 137 * in early init. 138 */ 139 struct lsm_static_calls_table 140 static_calls_table __ro_after_init __aligned(sizeof(u64)) = { 141 #define INIT_LSM_STATIC_CALL(NUM, NAME) \ 142 (struct lsm_static_call) { \ 143 .key = &STATIC_CALL_KEY(LSM_STATIC_CALL(NAME, NUM)), \ 144 .trampoline = LSM_HOOK_TRAMP(NAME, NUM), \ 145 .active = &SECURITY_HOOK_ACTIVE_KEY(NAME, NUM), \ 146 }, 147 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \ 148 .NAME = { \ 149 LSM_DEFINE_UNROLL(INIT_LSM_STATIC_CALL, NAME) \ 150 }, 151 #include <linux/lsm_hook_defs.h> 152 #undef LSM_HOOK 153 #undef INIT_LSM_STATIC_CALL 154 }; 155 156 /** 157 * lsm_file_alloc - allocate a composite file blob 158 * @file: the file that needs a blob 159 * 160 * Allocate the file blob for all the modules 161 * 162 * Returns 0, or -ENOMEM if memory can't be allocated. 163 */ 164 static int lsm_file_alloc(struct file *file) 165 { 166 if (!lsm_file_cache) { 167 file->f_security = NULL; 168 return 0; 169 } 170 171 file->f_security = kmem_cache_zalloc(lsm_file_cache, GFP_KERNEL); 172 if (file->f_security == NULL) 173 return -ENOMEM; 174 return 0; 175 } 176 177 /** 178 * lsm_backing_file_alloc - allocate a composite backing file blob 179 * @backing_file: the backing file 180 * 181 * Allocate the backing file blob for all the modules. 182 * 183 * Returns 0, or -ENOMEM if memory can't be allocated. 184 */ 185 static int lsm_backing_file_alloc(struct file *backing_file) 186 { 187 void *blob; 188 189 if (!lsm_backing_file_cache) { 190 backing_file_set_security(backing_file, NULL); 191 return 0; 192 } 193 194 blob = kmem_cache_zalloc(lsm_backing_file_cache, GFP_KERNEL); 195 backing_file_set_security(backing_file, blob); 196 if (!blob) 197 return -ENOMEM; 198 return 0; 199 } 200 201 /** 202 * lsm_blob_alloc - allocate a composite blob 203 * @dest: the destination for the blob 204 * @size: the size of the blob 205 * @gfp: allocation type 206 * 207 * Allocate a blob for all the modules 208 * 209 * Returns 0, or -ENOMEM if memory can't be allocated. 210 */ 211 static int lsm_blob_alloc(void **dest, size_t size, gfp_t gfp) 212 { 213 if (size == 0) { 214 *dest = NULL; 215 return 0; 216 } 217 218 *dest = kzalloc(size, gfp); 219 if (*dest == NULL) 220 return -ENOMEM; 221 return 0; 222 } 223 224 /** 225 * lsm_cred_alloc - allocate a composite cred blob 226 * @cred: the cred that needs a blob 227 * @gfp: allocation type 228 * 229 * Allocate the cred blob for all the modules 230 * 231 * Returns 0, or -ENOMEM if memory can't be allocated. 232 */ 233 int lsm_cred_alloc(struct cred *cred, gfp_t gfp) 234 { 235 return lsm_blob_alloc(&cred->security, blob_sizes.lbs_cred, gfp); 236 } 237 238 /** 239 * lsm_inode_alloc - allocate a composite inode blob 240 * @inode: the inode that needs a blob 241 * @gfp: allocation flags 242 * 243 * Allocate the inode blob for all the modules 244 * 245 * Returns 0, or -ENOMEM if memory can't be allocated. 246 */ 247 static int lsm_inode_alloc(struct inode *inode, gfp_t gfp) 248 { 249 if (!lsm_inode_cache) { 250 inode->i_security = NULL; 251 return 0; 252 } 253 254 inode->i_security = kmem_cache_zalloc(lsm_inode_cache, gfp); 255 if (inode->i_security == NULL) 256 return -ENOMEM; 257 return 0; 258 } 259 260 /** 261 * lsm_task_alloc - allocate a composite task blob 262 * @task: the task that needs a blob 263 * 264 * Allocate the task blob for all the modules 265 * 266 * Returns 0, or -ENOMEM if memory can't be allocated. 267 */ 268 int lsm_task_alloc(struct task_struct *task) 269 { 270 return lsm_blob_alloc(&task->security, blob_sizes.lbs_task, GFP_KERNEL); 271 } 272 273 /** 274 * lsm_ipc_alloc - allocate a composite ipc blob 275 * @kip: the ipc that needs a blob 276 * 277 * Allocate the ipc blob for all the modules 278 * 279 * Returns 0, or -ENOMEM if memory can't be allocated. 280 */ 281 static int lsm_ipc_alloc(struct kern_ipc_perm *kip) 282 { 283 return lsm_blob_alloc(&kip->security, blob_sizes.lbs_ipc, GFP_KERNEL); 284 } 285 286 #ifdef CONFIG_KEYS 287 /** 288 * lsm_key_alloc - allocate a composite key blob 289 * @key: the key that needs a blob 290 * 291 * Allocate the key blob for all the modules 292 * 293 * Returns 0, or -ENOMEM if memory can't be allocated. 294 */ 295 static int lsm_key_alloc(struct key *key) 296 { 297 return lsm_blob_alloc(&key->security, blob_sizes.lbs_key, GFP_KERNEL); 298 } 299 #endif /* CONFIG_KEYS */ 300 301 /** 302 * lsm_msg_msg_alloc - allocate a composite msg_msg blob 303 * @mp: the msg_msg that needs a blob 304 * 305 * Allocate the ipc blob for all the modules 306 * 307 * Returns 0, or -ENOMEM if memory can't be allocated. 308 */ 309 static int lsm_msg_msg_alloc(struct msg_msg *mp) 310 { 311 return lsm_blob_alloc(&mp->security, blob_sizes.lbs_msg_msg, 312 GFP_KERNEL); 313 } 314 315 /** 316 * lsm_bdev_alloc - allocate a composite block_device blob 317 * @bdev: the block_device that needs a blob 318 * 319 * Allocate the block_device blob for all the modules 320 * 321 * Returns 0, or -ENOMEM if memory can't be allocated. 322 */ 323 static int lsm_bdev_alloc(struct block_device *bdev) 324 { 325 return lsm_blob_alloc(&bdev->bd_security, blob_sizes.lbs_bdev, 326 GFP_KERNEL); 327 } 328 329 #ifdef CONFIG_BPF_SYSCALL 330 /** 331 * lsm_bpf_map_alloc - allocate a composite bpf_map blob 332 * @map: the bpf_map that needs a blob 333 * 334 * Allocate the bpf_map blob for all the modules 335 * 336 * Returns 0, or -ENOMEM if memory can't be allocated. 337 */ 338 static int lsm_bpf_map_alloc(struct bpf_map *map) 339 { 340 return lsm_blob_alloc(&map->security, blob_sizes.lbs_bpf_map, GFP_KERNEL); 341 } 342 343 /** 344 * lsm_bpf_prog_alloc - allocate a composite bpf_prog blob 345 * @prog: the bpf_prog that needs a blob 346 * 347 * Allocate the bpf_prog blob for all the modules 348 * 349 * Returns 0, or -ENOMEM if memory can't be allocated. 350 */ 351 static int lsm_bpf_prog_alloc(struct bpf_prog *prog) 352 { 353 return lsm_blob_alloc(&prog->aux->security, blob_sizes.lbs_bpf_prog, GFP_KERNEL); 354 } 355 356 /** 357 * lsm_bpf_token_alloc - allocate a composite bpf_token blob 358 * @token: the bpf_token that needs a blob 359 * 360 * Allocate the bpf_token blob for all the modules 361 * 362 * Returns 0, or -ENOMEM if memory can't be allocated. 363 */ 364 static int lsm_bpf_token_alloc(struct bpf_token *token) 365 { 366 return lsm_blob_alloc(&token->security, blob_sizes.lbs_bpf_token, GFP_KERNEL); 367 } 368 #endif /* CONFIG_BPF_SYSCALL */ 369 370 /** 371 * lsm_superblock_alloc - allocate a composite superblock blob 372 * @sb: the superblock that needs a blob 373 * 374 * Allocate the superblock blob for all the modules 375 * 376 * Returns 0, or -ENOMEM if memory can't be allocated. 377 */ 378 static int lsm_superblock_alloc(struct super_block *sb) 379 { 380 return lsm_blob_alloc(&sb->s_security, blob_sizes.lbs_superblock, 381 GFP_KERNEL); 382 } 383 384 /** 385 * lsm_fill_user_ctx - Fill a user space lsm_ctx structure 386 * @uctx: a userspace LSM context to be filled 387 * @uctx_len: available uctx size (input), used uctx size (output) 388 * @val: the new LSM context value 389 * @val_len: the size of the new LSM context value 390 * @id: LSM id 391 * @flags: LSM defined flags 392 * 393 * Fill all of the fields in a userspace lsm_ctx structure. If @uctx is NULL 394 * simply calculate the required size to output via @utc_len and return 395 * success. 396 * 397 * Returns 0 on success, -E2BIG if userspace buffer is not large enough, 398 * -EFAULT on a copyout error, -ENOMEM if memory can't be allocated. 399 */ 400 int lsm_fill_user_ctx(struct lsm_ctx __user *uctx, u32 *uctx_len, 401 void *val, size_t val_len, 402 u64 id, u64 flags) 403 { 404 struct lsm_ctx *nctx = NULL; 405 size_t nctx_len; 406 int rc = 0; 407 408 nctx_len = ALIGN(struct_size(nctx, ctx, val_len), sizeof(void *)); 409 if (nctx_len > *uctx_len) { 410 rc = -E2BIG; 411 goto out; 412 } 413 414 /* no buffer - return success/0 and set @uctx_len to the req size */ 415 if (!uctx) 416 goto out; 417 418 nctx = kzalloc(nctx_len, GFP_KERNEL); 419 if (nctx == NULL) { 420 rc = -ENOMEM; 421 goto out; 422 } 423 nctx->id = id; 424 nctx->flags = flags; 425 nctx->len = nctx_len; 426 nctx->ctx_len = val_len; 427 memcpy(nctx->ctx, val, val_len); 428 429 if (copy_to_user(uctx, nctx, nctx_len)) 430 rc = -EFAULT; 431 432 out: 433 kfree(nctx); 434 *uctx_len = nctx_len; 435 return rc; 436 } 437 438 /* 439 * The default value of the LSM hook is defined in linux/lsm_hook_defs.h and 440 * can be accessed with: 441 * 442 * LSM_RET_DEFAULT(<hook_name>) 443 * 444 * The macros below define static constants for the default value of each 445 * LSM hook. 446 */ 447 #define LSM_RET_DEFAULT(NAME) (NAME##_default) 448 #define DECLARE_LSM_RET_DEFAULT_void(DEFAULT, NAME) 449 #define DECLARE_LSM_RET_DEFAULT_int(DEFAULT, NAME) \ 450 static const int __maybe_unused LSM_RET_DEFAULT(NAME) = (DEFAULT); 451 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \ 452 DECLARE_LSM_RET_DEFAULT_##RET(DEFAULT, NAME) 453 454 #include <linux/lsm_hook_defs.h> 455 #undef LSM_HOOK 456 457 /* 458 * Hook list operation macros. 459 * 460 * call_void_hook: 461 * This is a hook that does not return a value. 462 * 463 * call_int_hook: 464 * This is a hook that returns a value. 465 */ 466 #define __CALL_STATIC_VOID(NUM, HOOK, ...) \ 467 do { \ 468 if (static_branch_unlikely(&SECURITY_HOOK_ACTIVE_KEY(HOOK, NUM))) { \ 469 static_call(LSM_STATIC_CALL(HOOK, NUM))(__VA_ARGS__); \ 470 } \ 471 } while (0); 472 473 #define call_void_hook(HOOK, ...) \ 474 do { \ 475 LSM_LOOP_UNROLL(__CALL_STATIC_VOID, HOOK, __VA_ARGS__); \ 476 } while (0) 477 478 479 #define __CALL_STATIC_INT(NUM, R, HOOK, LABEL, ...) \ 480 do { \ 481 if (static_branch_unlikely(&SECURITY_HOOK_ACTIVE_KEY(HOOK, NUM))) { \ 482 R = static_call(LSM_STATIC_CALL(HOOK, NUM))(__VA_ARGS__); \ 483 if (R != LSM_RET_DEFAULT(HOOK)) \ 484 goto LABEL; \ 485 } \ 486 } while (0); 487 488 #define call_int_hook(HOOK, ...) \ 489 ({ \ 490 __label__ OUT; \ 491 int RC = LSM_RET_DEFAULT(HOOK); \ 492 \ 493 LSM_LOOP_UNROLL(__CALL_STATIC_INT, RC, HOOK, OUT, __VA_ARGS__); \ 494 OUT: \ 495 RC; \ 496 }) 497 498 #define lsm_for_each_hook(scall, NAME) \ 499 for (scall = static_calls_table.NAME; \ 500 scall - static_calls_table.NAME < MAX_LSM_COUNT; scall++) \ 501 if (static_key_enabled(&scall->active->key)) 502 503 /* Security operations */ 504 505 /** 506 * security_binder_set_context_mgr() - Check if becoming binder ctx mgr is ok 507 * @mgr: task credentials of current binder process 508 * 509 * Check whether @mgr is allowed to be the binder context manager. 510 * 511 * Return: Return 0 if permission is granted. 512 */ 513 int security_binder_set_context_mgr(const struct cred *mgr) 514 { 515 return call_int_hook(binder_set_context_mgr, mgr); 516 } 517 518 /** 519 * security_binder_transaction() - Check if a binder transaction is allowed 520 * @from: sending process 521 * @to: receiving process 522 * 523 * Check whether @from is allowed to invoke a binder transaction call to @to. 524 * 525 * Return: Returns 0 if permission is granted. 526 */ 527 int security_binder_transaction(const struct cred *from, 528 const struct cred *to) 529 { 530 return call_int_hook(binder_transaction, from, to); 531 } 532 533 /** 534 * security_binder_transfer_binder() - Check if a binder transfer is allowed 535 * @from: sending process 536 * @to: receiving process 537 * 538 * Check whether @from is allowed to transfer a binder reference to @to. 539 * 540 * Return: Returns 0 if permission is granted. 541 */ 542 int security_binder_transfer_binder(const struct cred *from, 543 const struct cred *to) 544 { 545 return call_int_hook(binder_transfer_binder, from, to); 546 } 547 548 /** 549 * security_binder_transfer_file() - Check if a binder file xfer is allowed 550 * @from: sending process 551 * @to: receiving process 552 * @file: file being transferred 553 * 554 * Check whether @from is allowed to transfer @file to @to. 555 * 556 * Return: Returns 0 if permission is granted. 557 */ 558 int security_binder_transfer_file(const struct cred *from, 559 const struct cred *to, const struct file *file) 560 { 561 return call_int_hook(binder_transfer_file, from, to, file); 562 } 563 564 /** 565 * security_ptrace_access_check() - Check if tracing is allowed 566 * @child: target process 567 * @mode: PTRACE_MODE flags 568 * 569 * Check permission before allowing the current process to trace the @child 570 * process. Security modules may also want to perform a process tracing check 571 * during an execve in the set_security or apply_creds hooks of tracing check 572 * during an execve in the bprm_set_creds hook of binprm_security_ops if the 573 * process is being traced and its security attributes would be changed by the 574 * execve. 575 * 576 * Return: Returns 0 if permission is granted. 577 */ 578 int security_ptrace_access_check(struct task_struct *child, unsigned int mode) 579 { 580 return call_int_hook(ptrace_access_check, child, mode); 581 } 582 583 /** 584 * security_ptrace_traceme() - Check if tracing is allowed 585 * @parent: tracing process 586 * 587 * Check that the @parent process has sufficient permission to trace the 588 * current process before allowing the current process to present itself to the 589 * @parent process for tracing. 590 * 591 * Return: Returns 0 if permission is granted. 592 */ 593 int security_ptrace_traceme(struct task_struct *parent) 594 { 595 return call_int_hook(ptrace_traceme, parent); 596 } 597 598 /** 599 * security_capget() - Get the capability sets for a process 600 * @target: target process 601 * @effective: effective capability set 602 * @inheritable: inheritable capability set 603 * @permitted: permitted capability set 604 * 605 * Get the @effective, @inheritable, and @permitted capability sets for the 606 * @target process. The hook may also perform permission checking to determine 607 * if the current process is allowed to see the capability sets of the @target 608 * process. 609 * 610 * Return: Returns 0 if the capability sets were successfully obtained. 611 */ 612 int security_capget(const struct task_struct *target, 613 kernel_cap_t *effective, 614 kernel_cap_t *inheritable, 615 kernel_cap_t *permitted) 616 { 617 return call_int_hook(capget, target, effective, inheritable, permitted); 618 } 619 620 /** 621 * security_capset() - Set the capability sets for a process 622 * @new: new credentials for the target process 623 * @old: current credentials of the target process 624 * @effective: effective capability set 625 * @inheritable: inheritable capability set 626 * @permitted: permitted capability set 627 * 628 * Set the @effective, @inheritable, and @permitted capability sets for the 629 * current process. 630 * 631 * Return: Returns 0 and update @new if permission is granted. 632 */ 633 int security_capset(struct cred *new, const struct cred *old, 634 const kernel_cap_t *effective, 635 const kernel_cap_t *inheritable, 636 const kernel_cap_t *permitted) 637 { 638 return call_int_hook(capset, new, old, effective, inheritable, 639 permitted); 640 } 641 642 /** 643 * security_capable() - Check if a process has the necessary capability 644 * @cred: credentials to examine 645 * @ns: user namespace 646 * @cap: capability requested 647 * @opts: capability check options 648 * 649 * Check whether the @tsk process has the @cap capability in the indicated 650 * credentials. @cap contains the capability <include/linux/capability.h>. 651 * @opts contains options for the capable check <include/linux/security.h>. 652 * 653 * Return: Returns 0 if the capability is granted. 654 */ 655 int security_capable(const struct cred *cred, 656 struct user_namespace *ns, 657 int cap, 658 unsigned int opts) 659 { 660 return call_int_hook(capable, cred, ns, cap, opts); 661 } 662 663 /** 664 * security_quotactl() - Check if a quotactl() syscall is allowed for this fs 665 * @cmds: commands 666 * @type: type 667 * @id: id 668 * @sb: filesystem 669 * 670 * Check whether the quotactl syscall is allowed for this @sb. 671 * 672 * Return: Returns 0 if permission is granted. 673 */ 674 int security_quotactl(int cmds, int type, int id, const struct super_block *sb) 675 { 676 return call_int_hook(quotactl, cmds, type, id, sb); 677 } 678 679 /** 680 * security_quota_on() - Check if QUOTAON is allowed for a dentry 681 * @dentry: dentry 682 * 683 * Check whether QUOTAON is allowed for @dentry. 684 * 685 * Return: Returns 0 if permission is granted. 686 */ 687 int security_quota_on(struct dentry *dentry) 688 { 689 return call_int_hook(quota_on, dentry); 690 } 691 692 /** 693 * security_syslog() - Check if accessing the kernel message ring is allowed 694 * @type: SYSLOG_ACTION_* type 695 * 696 * Check permission before accessing the kernel message ring or changing 697 * logging to the console. See the syslog(2) manual page for an explanation of 698 * the @type values. 699 * 700 * Return: Return 0 if permission is granted. 701 */ 702 int security_syslog(int type) 703 { 704 return call_int_hook(syslog, type); 705 } 706 707 /** 708 * security_settime64() - Check if changing the system time is allowed 709 * @ts: new time 710 * @tz: timezone 711 * 712 * Check permission to change the system time, struct timespec64 is defined in 713 * <include/linux/time64.h> and timezone is defined in <include/linux/time.h>. 714 * 715 * Return: Returns 0 if permission is granted. 716 */ 717 int security_settime64(const struct timespec64 *ts, const struct timezone *tz) 718 { 719 return call_int_hook(settime, ts, tz); 720 } 721 722 /** 723 * security_vm_enough_memory_mm() - Check if allocating a new mem map is allowed 724 * @mm: mm struct 725 * @pages: number of pages 726 * 727 * Check permissions for allocating a new virtual mapping. If all LSMs return 728 * a positive value, __vm_enough_memory() will be called with cap_sys_admin 729 * set. If at least one LSM returns 0 or negative, __vm_enough_memory() will be 730 * called with cap_sys_admin cleared. 731 * 732 * Return: Returns 0 if permission is granted by the LSM infrastructure to the 733 * caller. 734 */ 735 int security_vm_enough_memory_mm(struct mm_struct *mm, long pages) 736 { 737 struct lsm_static_call *scall; 738 int cap_sys_admin = 1; 739 int rc; 740 741 /* 742 * The module will respond with 0 if it thinks the __vm_enough_memory() 743 * call should be made with the cap_sys_admin set. If all of the modules 744 * agree that it should be set it will. If any module thinks it should 745 * not be set it won't. 746 */ 747 lsm_for_each_hook(scall, vm_enough_memory) { 748 rc = scall->hl->hook.vm_enough_memory(mm, pages); 749 if (rc < 0) { 750 cap_sys_admin = 0; 751 break; 752 } 753 } 754 return __vm_enough_memory(mm, pages, cap_sys_admin); 755 } 756 757 /** 758 * security_bprm_creds_for_exec() - Prepare the credentials for exec() 759 * @bprm: binary program information 760 * 761 * If the setup in prepare_exec_creds did not setup @bprm->cred->security 762 * properly for executing @bprm->file, update the LSM's portion of 763 * @bprm->cred->security to be what commit_creds needs to install for the new 764 * program. This hook may also optionally check permissions (e.g. for 765 * transitions between security domains). The hook must set @bprm->secureexec 766 * to 1 if AT_SECURE should be set to request libc enable secure mode. @bprm 767 * contains the linux_binprm structure. 768 * 769 * If execveat(2) is called with the AT_EXECVE_CHECK flag, bprm->is_check is 770 * set. The result must be the same as without this flag even if the execution 771 * will never really happen and @bprm will always be dropped. 772 * 773 * This hook must not change current->cred, only @bprm->cred. 774 * 775 * Return: Returns 0 if the hook is successful and permission is granted. 776 */ 777 int security_bprm_creds_for_exec(struct linux_binprm *bprm) 778 { 779 return call_int_hook(bprm_creds_for_exec, bprm); 780 } 781 782 /** 783 * security_bprm_creds_from_file() - Update linux_binprm creds based on file 784 * @bprm: binary program information 785 * @file: associated file 786 * 787 * If @file is setpcap, suid, sgid or otherwise marked to change privilege upon 788 * exec, update @bprm->cred to reflect that change. This is called after 789 * finding the binary that will be executed without an interpreter. This 790 * ensures that the credentials will not be derived from a script that the 791 * binary will need to reopen, which when reopend may end up being a completely 792 * different file. This hook may also optionally check permissions (e.g. for 793 * transitions between security domains). The hook must set @bprm->secureexec 794 * to 1 if AT_SECURE should be set to request libc enable secure mode. The 795 * hook must add to @bprm->per_clear any personality flags that should be 796 * cleared from current->personality. @bprm contains the linux_binprm 797 * structure. 798 * 799 * Return: Returns 0 if the hook is successful and permission is granted. 800 */ 801 int security_bprm_creds_from_file(struct linux_binprm *bprm, const struct file *file) 802 { 803 return call_int_hook(bprm_creds_from_file, bprm, file); 804 } 805 806 /** 807 * security_bprm_check() - Mediate binary handler search 808 * @bprm: binary program information 809 * 810 * This hook mediates the point when a search for a binary handler will begin. 811 * It allows a check against the @bprm->cred->security value which was set in 812 * the preceding creds_for_exec call. The argv list and envp list are reliably 813 * available in @bprm. This hook may be called multiple times during a single 814 * execve. @bprm contains the linux_binprm structure. 815 * 816 * Return: Returns 0 if the hook is successful and permission is granted. 817 */ 818 int security_bprm_check(struct linux_binprm *bprm) 819 { 820 return call_int_hook(bprm_check_security, bprm); 821 } 822 823 /** 824 * security_bprm_committing_creds() - Install creds for a process during exec() 825 * @bprm: binary program information 826 * 827 * Prepare to install the new security attributes of a process being 828 * transformed by an execve operation, based on the old credentials pointed to 829 * by @current->cred and the information set in @bprm->cred by the 830 * bprm_creds_for_exec hook. @bprm points to the linux_binprm structure. This 831 * hook is a good place to perform state changes on the process such as closing 832 * open file descriptors to which access will no longer be granted when the 833 * attributes are changed. This is called immediately before commit_creds(). 834 */ 835 void security_bprm_committing_creds(const struct linux_binprm *bprm) 836 { 837 call_void_hook(bprm_committing_creds, bprm); 838 } 839 840 /** 841 * security_bprm_committed_creds() - Tidy up after cred install during exec() 842 * @bprm: binary program information 843 * 844 * Tidy up after the installation of the new security attributes of a process 845 * being transformed by an execve operation. The new credentials have, by this 846 * point, been set to @current->cred. @bprm points to the linux_binprm 847 * structure. This hook is a good place to perform state changes on the 848 * process such as clearing out non-inheritable signal state. This is called 849 * immediately after commit_creds(). 850 */ 851 void security_bprm_committed_creds(const struct linux_binprm *bprm) 852 { 853 call_void_hook(bprm_committed_creds, bprm); 854 } 855 856 /** 857 * security_fs_context_submount() - Initialise fc->security 858 * @fc: new filesystem context 859 * @reference: dentry reference for submount/remount 860 * 861 * Fill out the ->security field for a new fs_context. 862 * 863 * Return: Returns 0 on success or negative error code on failure. 864 */ 865 int security_fs_context_submount(struct fs_context *fc, struct super_block *reference) 866 { 867 return call_int_hook(fs_context_submount, fc, reference); 868 } 869 870 /** 871 * security_fs_context_dup() - Duplicate a fs_context LSM blob 872 * @fc: destination filesystem context 873 * @src_fc: source filesystem context 874 * 875 * Allocate and attach a security structure to sc->security. This pointer is 876 * initialised to NULL by the caller. @fc indicates the new filesystem context. 877 * @src_fc indicates the original filesystem context. 878 * 879 * Return: Returns 0 on success or a negative error code on failure. 880 */ 881 int security_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc) 882 { 883 return call_int_hook(fs_context_dup, fc, src_fc); 884 } 885 886 /** 887 * security_fs_context_parse_param() - Configure a filesystem context 888 * @fc: filesystem context 889 * @param: filesystem parameter 890 * 891 * Userspace provided a parameter to configure a superblock. The LSM can 892 * consume the parameter or return it to the caller for use elsewhere. 893 * 894 * Return: If the parameter is used by the LSM it should return 0, if it is 895 * returned to the caller -ENOPARAM is returned, otherwise a negative 896 * error code is returned. 897 */ 898 int security_fs_context_parse_param(struct fs_context *fc, 899 struct fs_parameter *param) 900 { 901 struct lsm_static_call *scall; 902 int trc; 903 int rc = -ENOPARAM; 904 905 lsm_for_each_hook(scall, fs_context_parse_param) { 906 trc = scall->hl->hook.fs_context_parse_param(fc, param); 907 if (trc == 0) 908 rc = 0; 909 else if (trc != -ENOPARAM) 910 return trc; 911 } 912 return rc; 913 } 914 915 /** 916 * security_sb_alloc() - Allocate a super_block LSM blob 917 * @sb: filesystem superblock 918 * 919 * Allocate and attach a security structure to the sb->s_security field. The 920 * s_security field is initialized to NULL when the structure is allocated. 921 * @sb contains the super_block structure to be modified. 922 * 923 * Return: Returns 0 if operation was successful. 924 */ 925 int security_sb_alloc(struct super_block *sb) 926 { 927 int rc = lsm_superblock_alloc(sb); 928 929 if (unlikely(rc)) 930 return rc; 931 rc = call_int_hook(sb_alloc_security, sb); 932 if (unlikely(rc)) 933 security_sb_free(sb); 934 return rc; 935 } 936 937 /** 938 * security_sb_delete() - Release super_block LSM associated objects 939 * @sb: filesystem superblock 940 * 941 * Release objects tied to a superblock (e.g. inodes). @sb contains the 942 * super_block structure being released. 943 */ 944 void security_sb_delete(struct super_block *sb) 945 { 946 call_void_hook(sb_delete, sb); 947 } 948 949 /** 950 * security_sb_free() - Free a super_block LSM blob 951 * @sb: filesystem superblock 952 * 953 * Deallocate and clear the sb->s_security field. @sb contains the super_block 954 * structure to be modified. 955 */ 956 void security_sb_free(struct super_block *sb) 957 { 958 call_void_hook(sb_free_security, sb); 959 kfree(sb->s_security); 960 sb->s_security = NULL; 961 } 962 963 /** 964 * security_free_mnt_opts() - Free memory associated with mount options 965 * @mnt_opts: LSM processed mount options 966 * 967 * Free memory associated with @mnt_ops. 968 */ 969 void security_free_mnt_opts(void **mnt_opts) 970 { 971 if (!*mnt_opts) 972 return; 973 call_void_hook(sb_free_mnt_opts, *mnt_opts); 974 *mnt_opts = NULL; 975 } 976 EXPORT_SYMBOL(security_free_mnt_opts); 977 978 /** 979 * security_sb_eat_lsm_opts() - Consume LSM mount options 980 * @options: mount options 981 * @mnt_opts: LSM processed mount options 982 * 983 * Eat (scan @options) and save them in @mnt_opts. 984 * 985 * Return: Returns 0 on success, negative values on failure. 986 */ 987 int security_sb_eat_lsm_opts(char *options, void **mnt_opts) 988 { 989 return call_int_hook(sb_eat_lsm_opts, options, mnt_opts); 990 } 991 EXPORT_SYMBOL(security_sb_eat_lsm_opts); 992 993 /** 994 * security_sb_mnt_opts_compat() - Check if new mount options are allowed 995 * @sb: filesystem superblock 996 * @mnt_opts: new mount options 997 * 998 * Determine if the new mount options in @mnt_opts are allowed given the 999 * existing mounted filesystem at @sb. @sb superblock being compared. 1000 * 1001 * Return: Returns 0 if options are compatible. 1002 */ 1003 int security_sb_mnt_opts_compat(struct super_block *sb, 1004 void *mnt_opts) 1005 { 1006 return call_int_hook(sb_mnt_opts_compat, sb, mnt_opts); 1007 } 1008 EXPORT_SYMBOL(security_sb_mnt_opts_compat); 1009 1010 /** 1011 * security_sb_remount() - Verify no incompatible mount changes during remount 1012 * @sb: filesystem superblock 1013 * @mnt_opts: (re)mount options 1014 * 1015 * Extracts security system specific mount options and verifies no changes are 1016 * being made to those options. 1017 * 1018 * Return: Returns 0 if permission is granted. 1019 */ 1020 int security_sb_remount(struct super_block *sb, 1021 void *mnt_opts) 1022 { 1023 return call_int_hook(sb_remount, sb, mnt_opts); 1024 } 1025 EXPORT_SYMBOL(security_sb_remount); 1026 1027 /** 1028 * security_sb_kern_mount() - Check if a kernel mount is allowed 1029 * @sb: filesystem superblock 1030 * 1031 * Mount this @sb if allowed by permissions. 1032 * 1033 * Return: Returns 0 if permission is granted. 1034 */ 1035 int security_sb_kern_mount(const struct super_block *sb) 1036 { 1037 return call_int_hook(sb_kern_mount, sb); 1038 } 1039 1040 /** 1041 * security_sb_show_options() - Output the mount options for a superblock 1042 * @m: output file 1043 * @sb: filesystem superblock 1044 * 1045 * Show (print on @m) mount options for this @sb. 1046 * 1047 * Return: Returns 0 on success, negative values on failure. 1048 */ 1049 int security_sb_show_options(struct seq_file *m, struct super_block *sb) 1050 { 1051 return call_int_hook(sb_show_options, m, sb); 1052 } 1053 1054 /** 1055 * security_sb_statfs() - Check if accessing fs stats is allowed 1056 * @dentry: superblock handle 1057 * 1058 * Check permission before obtaining filesystem statistics for the @mnt 1059 * mountpoint. @dentry is a handle on the superblock for the filesystem. 1060 * 1061 * Return: Returns 0 if permission is granted. 1062 */ 1063 int security_sb_statfs(struct dentry *dentry) 1064 { 1065 return call_int_hook(sb_statfs, dentry); 1066 } 1067 1068 /** 1069 * security_sb_mount() - Check permission for mounting a filesystem 1070 * @dev_name: filesystem backing device 1071 * @path: mount point 1072 * @type: filesystem type 1073 * @flags: mount flags 1074 * @data: filesystem specific data 1075 * 1076 * Check permission before an object specified by @dev_name is mounted on the 1077 * mount point named by @nd. For an ordinary mount, @dev_name identifies a 1078 * device if the file system type requires a device. For a remount 1079 * (@flags & MS_REMOUNT), @dev_name is irrelevant. For a loopback/bind mount 1080 * (@flags & MS_BIND), @dev_name identifies the pathname of the object being 1081 * mounted. 1082 * 1083 * Return: Returns 0 if permission is granted. 1084 */ 1085 int security_sb_mount(const char *dev_name, const struct path *path, 1086 const char *type, unsigned long flags, void *data) 1087 { 1088 return call_int_hook(sb_mount, dev_name, path, type, flags, data); 1089 } 1090 1091 /** 1092 * security_sb_umount() - Check permission for unmounting a filesystem 1093 * @mnt: mounted filesystem 1094 * @flags: unmount flags 1095 * 1096 * Check permission before the @mnt file system is unmounted. 1097 * 1098 * Return: Returns 0 if permission is granted. 1099 */ 1100 int security_sb_umount(struct vfsmount *mnt, int flags) 1101 { 1102 return call_int_hook(sb_umount, mnt, flags); 1103 } 1104 1105 /** 1106 * security_sb_pivotroot() - Check permissions for pivoting the rootfs 1107 * @old_path: new location for current rootfs 1108 * @new_path: location of the new rootfs 1109 * 1110 * Check permission before pivoting the root filesystem. 1111 * 1112 * Return: Returns 0 if permission is granted. 1113 */ 1114 int security_sb_pivotroot(const struct path *old_path, 1115 const struct path *new_path) 1116 { 1117 return call_int_hook(sb_pivotroot, old_path, new_path); 1118 } 1119 1120 /** 1121 * security_sb_set_mnt_opts() - Set the mount options for a filesystem 1122 * @sb: filesystem superblock 1123 * @mnt_opts: binary mount options 1124 * @kern_flags: kernel flags (in) 1125 * @set_kern_flags: kernel flags (out) 1126 * 1127 * Set the security relevant mount options used for a superblock. 1128 * 1129 * Return: Returns 0 on success, error on failure. 1130 */ 1131 int security_sb_set_mnt_opts(struct super_block *sb, 1132 void *mnt_opts, 1133 unsigned long kern_flags, 1134 unsigned long *set_kern_flags) 1135 { 1136 struct lsm_static_call *scall; 1137 int rc = mnt_opts ? -EOPNOTSUPP : LSM_RET_DEFAULT(sb_set_mnt_opts); 1138 1139 lsm_for_each_hook(scall, sb_set_mnt_opts) { 1140 rc = scall->hl->hook.sb_set_mnt_opts(sb, mnt_opts, kern_flags, 1141 set_kern_flags); 1142 if (rc != LSM_RET_DEFAULT(sb_set_mnt_opts)) 1143 break; 1144 } 1145 return rc; 1146 } 1147 EXPORT_SYMBOL(security_sb_set_mnt_opts); 1148 1149 /** 1150 * security_sb_clone_mnt_opts() - Duplicate superblock mount options 1151 * @oldsb: source superblock 1152 * @newsb: destination superblock 1153 * @kern_flags: kernel flags (in) 1154 * @set_kern_flags: kernel flags (out) 1155 * 1156 * Copy all security options from a given superblock to another. 1157 * 1158 * Return: Returns 0 on success, error on failure. 1159 */ 1160 int security_sb_clone_mnt_opts(const struct super_block *oldsb, 1161 struct super_block *newsb, 1162 unsigned long kern_flags, 1163 unsigned long *set_kern_flags) 1164 { 1165 return call_int_hook(sb_clone_mnt_opts, oldsb, newsb, 1166 kern_flags, set_kern_flags); 1167 } 1168 EXPORT_SYMBOL(security_sb_clone_mnt_opts); 1169 1170 /** 1171 * security_move_mount() - Check permissions for moving a mount 1172 * @from_path: source mount point 1173 * @to_path: destination mount point 1174 * 1175 * Check permission before a mount is moved. 1176 * 1177 * Return: Returns 0 if permission is granted. 1178 */ 1179 int security_move_mount(const struct path *from_path, 1180 const struct path *to_path) 1181 { 1182 return call_int_hook(move_mount, from_path, to_path); 1183 } 1184 1185 /** 1186 * security_path_notify() - Check if setting a watch is allowed 1187 * @path: file path 1188 * @mask: event mask 1189 * @obj_type: file path type 1190 * 1191 * Check permissions before setting a watch on events as defined by @mask, on 1192 * an object at @path, whose type is defined by @obj_type. 1193 * 1194 * Return: Returns 0 if permission is granted. 1195 */ 1196 int security_path_notify(const struct path *path, u64 mask, 1197 unsigned int obj_type) 1198 { 1199 return call_int_hook(path_notify, path, mask, obj_type); 1200 } 1201 1202 /** 1203 * security_inode_alloc() - Allocate an inode LSM blob 1204 * @inode: the inode 1205 * @gfp: allocation flags 1206 * 1207 * Allocate and attach a security structure to @inode->i_security. The 1208 * i_security field is initialized to NULL when the inode structure is 1209 * allocated. 1210 * 1211 * Return: Return 0 if operation was successful. 1212 */ 1213 int security_inode_alloc(struct inode *inode, gfp_t gfp) 1214 { 1215 int rc = lsm_inode_alloc(inode, gfp); 1216 1217 if (unlikely(rc)) 1218 return rc; 1219 rc = call_int_hook(inode_alloc_security, inode); 1220 if (unlikely(rc)) 1221 security_inode_free(inode); 1222 return rc; 1223 } 1224 1225 static void inode_free_by_rcu(struct rcu_head *head) 1226 { 1227 /* The rcu head is at the start of the inode blob */ 1228 call_void_hook(inode_free_security_rcu, head); 1229 kmem_cache_free(lsm_inode_cache, head); 1230 } 1231 1232 /** 1233 * security_inode_free() - Free an inode's LSM blob 1234 * @inode: the inode 1235 * 1236 * Release any LSM resources associated with @inode, although due to the 1237 * inode's RCU protections it is possible that the resources will not be 1238 * fully released until after the current RCU grace period has elapsed. 1239 * 1240 * It is important for LSMs to note that despite being present in a call to 1241 * security_inode_free(), @inode may still be referenced in a VFS path walk 1242 * and calls to security_inode_permission() may be made during, or after, 1243 * a call to security_inode_free(). For this reason the inode->i_security 1244 * field is released via a call_rcu() callback and any LSMs which need to 1245 * retain inode state for use in security_inode_permission() should only 1246 * release that state in the inode_free_security_rcu() LSM hook callback. 1247 */ 1248 void security_inode_free(struct inode *inode) 1249 { 1250 call_void_hook(inode_free_security, inode); 1251 if (!inode->i_security) 1252 return; 1253 call_rcu((struct rcu_head *)inode->i_security, inode_free_by_rcu); 1254 } 1255 1256 /** 1257 * security_dentry_init_security() - Perform dentry initialization 1258 * @dentry: the dentry to initialize 1259 * @mode: mode used to determine resource type 1260 * @name: name of the last path component 1261 * @xattr_name: name of the security/LSM xattr 1262 * @lsmctx: pointer to the resulting LSM context 1263 * 1264 * Compute a context for a dentry as the inode is not yet available since NFSv4 1265 * has no label backed by an EA anyway. It is important to note that 1266 * @xattr_name does not need to be free'd by the caller, it is a static string. 1267 * 1268 * Return: Returns 0 on success, negative values on failure. 1269 */ 1270 int security_dentry_init_security(struct dentry *dentry, int mode, 1271 const struct qstr *name, 1272 const char **xattr_name, 1273 struct lsm_context *lsmctx) 1274 { 1275 return call_int_hook(dentry_init_security, dentry, mode, name, 1276 xattr_name, lsmctx); 1277 } 1278 EXPORT_SYMBOL(security_dentry_init_security); 1279 1280 /** 1281 * security_dentry_create_files_as() - Perform dentry initialization 1282 * @dentry: the dentry to initialize 1283 * @mode: mode used to determine resource type 1284 * @name: name of the last path component 1285 * @old: creds to use for LSM context calculations 1286 * @new: creds to modify 1287 * 1288 * Compute a context for a dentry as the inode is not yet available and set 1289 * that context in passed in creds so that new files are created using that 1290 * context. Context is calculated using the passed in creds and not the creds 1291 * of the caller. 1292 * 1293 * Return: Returns 0 on success, error on failure. 1294 */ 1295 int security_dentry_create_files_as(struct dentry *dentry, int mode, 1296 const struct qstr *name, 1297 const struct cred *old, struct cred *new) 1298 { 1299 return call_int_hook(dentry_create_files_as, dentry, mode, 1300 name, old, new); 1301 } 1302 EXPORT_SYMBOL(security_dentry_create_files_as); 1303 1304 /** 1305 * security_inode_init_security() - Initialize an inode's LSM context 1306 * @inode: the inode 1307 * @dir: parent directory 1308 * @qstr: last component of the pathname 1309 * @initxattrs: callback function to write xattrs 1310 * @fs_data: filesystem specific data 1311 * 1312 * Obtain the security attribute name suffix and value to set on a newly 1313 * created inode and set up the incore security field for the new inode. This 1314 * hook is called by the fs code as part of the inode creation transaction and 1315 * provides for atomic labeling of the inode, unlike the post_create/mkdir/... 1316 * hooks called by the VFS. 1317 * 1318 * The hook function is expected to populate the xattrs array, by calling 1319 * lsm_get_xattr_slot() to retrieve the slots reserved by the security module 1320 * with the lbs_xattr_count field of the lsm_blob_sizes structure. For each 1321 * slot, the hook function should set ->name to the attribute name suffix 1322 * (e.g. selinux), to allocate ->value (will be freed by the caller) and set it 1323 * to the attribute value, to set ->value_len to the length of the value. If 1324 * the security module does not use security attributes or does not wish to put 1325 * a security attribute on this particular inode, then it should return 1326 * -EOPNOTSUPP to skip this processing. 1327 * 1328 * Return: Returns 0 if the LSM successfully initialized all of the inode 1329 * security attributes that are required, negative values otherwise. 1330 */ 1331 int security_inode_init_security(struct inode *inode, struct inode *dir, 1332 const struct qstr *qstr, 1333 const initxattrs initxattrs, void *fs_data) 1334 { 1335 struct lsm_static_call *scall; 1336 struct xattr *new_xattrs = NULL; 1337 int ret = -EOPNOTSUPP, xattr_count = 0; 1338 1339 if (unlikely(IS_PRIVATE(inode))) 1340 return 0; 1341 1342 if (!blob_sizes.lbs_xattr_count) 1343 return 0; 1344 1345 if (initxattrs) { 1346 /* Allocate +1 as terminator. */ 1347 new_xattrs = kcalloc(blob_sizes.lbs_xattr_count + 1, 1348 sizeof(*new_xattrs), GFP_NOFS); 1349 if (!new_xattrs) 1350 return -ENOMEM; 1351 } 1352 1353 lsm_for_each_hook(scall, inode_init_security) { 1354 ret = scall->hl->hook.inode_init_security(inode, dir, qstr, new_xattrs, 1355 &xattr_count); 1356 if (ret && ret != -EOPNOTSUPP) 1357 goto out; 1358 /* 1359 * As documented in lsm_hooks.h, -EOPNOTSUPP in this context 1360 * means that the LSM is not willing to provide an xattr, not 1361 * that it wants to signal an error. Thus, continue to invoke 1362 * the remaining LSMs. 1363 */ 1364 } 1365 1366 /* If initxattrs() is NULL, xattr_count is zero, skip the call. */ 1367 if (!xattr_count) 1368 goto out; 1369 1370 ret = initxattrs(inode, new_xattrs, fs_data); 1371 out: 1372 for (; xattr_count > 0; xattr_count--) 1373 kfree(new_xattrs[xattr_count - 1].value); 1374 kfree(new_xattrs); 1375 return (ret == -EOPNOTSUPP) ? 0 : ret; 1376 } 1377 EXPORT_SYMBOL(security_inode_init_security); 1378 1379 /** 1380 * security_inode_init_security_anon() - Initialize an anonymous inode 1381 * @inode: the inode 1382 * @name: the anonymous inode class 1383 * @context_inode: an optional related inode 1384 * 1385 * Set up the incore security field for the new anonymous inode and return 1386 * whether the inode creation is permitted by the security module or not. 1387 * 1388 * Return: Returns 0 on success, -EACCES if the security module denies the 1389 * creation of this inode, or another -errno upon other errors. 1390 */ 1391 int security_inode_init_security_anon(struct inode *inode, 1392 const struct qstr *name, 1393 const struct inode *context_inode) 1394 { 1395 return call_int_hook(inode_init_security_anon, inode, name, 1396 context_inode); 1397 } 1398 1399 #ifdef CONFIG_SECURITY_PATH 1400 /** 1401 * security_path_mknod() - Check if creating a special file is allowed 1402 * @dir: parent directory 1403 * @dentry: new file 1404 * @mode: new file mode 1405 * @dev: device number 1406 * 1407 * Check permissions when creating a file. Note that this hook is called even 1408 * if mknod operation is being done for a regular file. 1409 * 1410 * Return: Returns 0 if permission is granted. 1411 */ 1412 int security_path_mknod(const struct path *dir, struct dentry *dentry, 1413 umode_t mode, unsigned int dev) 1414 { 1415 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1416 return 0; 1417 return call_int_hook(path_mknod, dir, dentry, mode, dev); 1418 } 1419 EXPORT_SYMBOL(security_path_mknod); 1420 1421 /** 1422 * security_path_post_mknod() - Update inode security after reg file creation 1423 * @idmap: idmap of the mount 1424 * @dentry: new file 1425 * 1426 * Update inode security field after a regular file has been created. 1427 */ 1428 void security_path_post_mknod(struct mnt_idmap *idmap, struct dentry *dentry) 1429 { 1430 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 1431 return; 1432 call_void_hook(path_post_mknod, idmap, dentry); 1433 } 1434 1435 /** 1436 * security_path_mkdir() - Check if creating a new directory is allowed 1437 * @dir: parent directory 1438 * @dentry: new directory 1439 * @mode: new directory mode 1440 * 1441 * Check permissions to create a new directory in the existing directory. 1442 * 1443 * Return: Returns 0 if permission is granted. 1444 */ 1445 int security_path_mkdir(const struct path *dir, struct dentry *dentry, 1446 umode_t mode) 1447 { 1448 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1449 return 0; 1450 return call_int_hook(path_mkdir, dir, dentry, mode); 1451 } 1452 EXPORT_SYMBOL(security_path_mkdir); 1453 1454 /** 1455 * security_path_rmdir() - Check if removing a directory is allowed 1456 * @dir: parent directory 1457 * @dentry: directory to remove 1458 * 1459 * Check the permission to remove a directory. 1460 * 1461 * Return: Returns 0 if permission is granted. 1462 */ 1463 int security_path_rmdir(const struct path *dir, struct dentry *dentry) 1464 { 1465 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1466 return 0; 1467 return call_int_hook(path_rmdir, dir, dentry); 1468 } 1469 1470 /** 1471 * security_path_unlink() - Check if removing a hard link is allowed 1472 * @dir: parent directory 1473 * @dentry: file 1474 * 1475 * Check the permission to remove a hard link to a file. 1476 * 1477 * Return: Returns 0 if permission is granted. 1478 */ 1479 int security_path_unlink(const struct path *dir, struct dentry *dentry) 1480 { 1481 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1482 return 0; 1483 return call_int_hook(path_unlink, dir, dentry); 1484 } 1485 EXPORT_SYMBOL(security_path_unlink); 1486 1487 /** 1488 * security_path_symlink() - Check if creating a symbolic link is allowed 1489 * @dir: parent directory 1490 * @dentry: symbolic link 1491 * @old_name: file pathname 1492 * 1493 * Check the permission to create a symbolic link to a file. 1494 * 1495 * Return: Returns 0 if permission is granted. 1496 */ 1497 int security_path_symlink(const struct path *dir, struct dentry *dentry, 1498 const char *old_name) 1499 { 1500 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1501 return 0; 1502 return call_int_hook(path_symlink, dir, dentry, old_name); 1503 } 1504 1505 /** 1506 * security_path_link - Check if creating a hard link is allowed 1507 * @old_dentry: existing file 1508 * @new_dir: new parent directory 1509 * @new_dentry: new link 1510 * 1511 * Check permission before creating a new hard link to a file. 1512 * 1513 * Return: Returns 0 if permission is granted. 1514 */ 1515 int security_path_link(struct dentry *old_dentry, const struct path *new_dir, 1516 struct dentry *new_dentry) 1517 { 1518 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)))) 1519 return 0; 1520 return call_int_hook(path_link, old_dentry, new_dir, new_dentry); 1521 } 1522 1523 /** 1524 * security_path_rename() - Check if renaming a file is allowed 1525 * @old_dir: parent directory of the old file 1526 * @old_dentry: the old file 1527 * @new_dir: parent directory of the new file 1528 * @new_dentry: the new file 1529 * @flags: flags 1530 * 1531 * Check for permission to rename a file or directory. 1532 * 1533 * Return: Returns 0 if permission is granted. 1534 */ 1535 int security_path_rename(const struct path *old_dir, struct dentry *old_dentry, 1536 const struct path *new_dir, struct dentry *new_dentry, 1537 unsigned int flags) 1538 { 1539 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) || 1540 (d_is_positive(new_dentry) && 1541 IS_PRIVATE(d_backing_inode(new_dentry))))) 1542 return 0; 1543 1544 return call_int_hook(path_rename, old_dir, old_dentry, new_dir, 1545 new_dentry, flags); 1546 } 1547 EXPORT_SYMBOL(security_path_rename); 1548 1549 /** 1550 * security_path_truncate() - Check if truncating a file is allowed 1551 * @path: file 1552 * 1553 * Check permission before truncating the file indicated by path. Note that 1554 * truncation permissions may also be checked based on already opened files, 1555 * using the security_file_truncate() hook. 1556 * 1557 * Return: Returns 0 if permission is granted. 1558 */ 1559 int security_path_truncate(const struct path *path) 1560 { 1561 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) 1562 return 0; 1563 return call_int_hook(path_truncate, path); 1564 } 1565 1566 /** 1567 * security_path_chmod() - Check if changing the file's mode is allowed 1568 * @path: file 1569 * @mode: new mode 1570 * 1571 * Check for permission to change a mode of the file @path. The new mode is 1572 * specified in @mode which is a bitmask of constants from 1573 * <include/uapi/linux/stat.h>. 1574 * 1575 * Return: Returns 0 if permission is granted. 1576 */ 1577 int security_path_chmod(const struct path *path, umode_t mode) 1578 { 1579 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) 1580 return 0; 1581 return call_int_hook(path_chmod, path, mode); 1582 } 1583 1584 /** 1585 * security_path_chown() - Check if changing the file's owner/group is allowed 1586 * @path: file 1587 * @uid: file owner 1588 * @gid: file group 1589 * 1590 * Check for permission to change owner/group of a file or directory. 1591 * 1592 * Return: Returns 0 if permission is granted. 1593 */ 1594 int security_path_chown(const struct path *path, kuid_t uid, kgid_t gid) 1595 { 1596 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) 1597 return 0; 1598 return call_int_hook(path_chown, path, uid, gid); 1599 } 1600 1601 /** 1602 * security_path_chroot() - Check if changing the root directory is allowed 1603 * @path: directory 1604 * 1605 * Check for permission to change root directory. 1606 * 1607 * Return: Returns 0 if permission is granted. 1608 */ 1609 int security_path_chroot(const struct path *path) 1610 { 1611 return call_int_hook(path_chroot, path); 1612 } 1613 #endif /* CONFIG_SECURITY_PATH */ 1614 1615 /** 1616 * security_inode_create() - Check if creating a file is allowed 1617 * @dir: the parent directory 1618 * @dentry: the file being created 1619 * @mode: requested file mode 1620 * 1621 * Check permission to create a regular file. 1622 * 1623 * Return: Returns 0 if permission is granted. 1624 */ 1625 int security_inode_create(struct inode *dir, struct dentry *dentry, 1626 umode_t mode) 1627 { 1628 if (unlikely(IS_PRIVATE(dir))) 1629 return 0; 1630 return call_int_hook(inode_create, dir, dentry, mode); 1631 } 1632 EXPORT_SYMBOL_GPL(security_inode_create); 1633 1634 /** 1635 * security_inode_post_create_tmpfile() - Update inode security of new tmpfile 1636 * @idmap: idmap of the mount 1637 * @inode: inode of the new tmpfile 1638 * 1639 * Update inode security data after a tmpfile has been created. 1640 */ 1641 void security_inode_post_create_tmpfile(struct mnt_idmap *idmap, 1642 struct inode *inode) 1643 { 1644 if (unlikely(IS_PRIVATE(inode))) 1645 return; 1646 call_void_hook(inode_post_create_tmpfile, idmap, inode); 1647 } 1648 1649 /** 1650 * security_inode_link() - Check if creating a hard link is allowed 1651 * @old_dentry: existing file 1652 * @dir: new parent directory 1653 * @new_dentry: new link 1654 * 1655 * Check permission before creating a new hard link to a file. 1656 * 1657 * Return: Returns 0 if permission is granted. 1658 */ 1659 int security_inode_link(struct dentry *old_dentry, struct inode *dir, 1660 struct dentry *new_dentry) 1661 { 1662 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)))) 1663 return 0; 1664 return call_int_hook(inode_link, old_dentry, dir, new_dentry); 1665 } 1666 1667 /** 1668 * security_inode_unlink() - Check if removing a hard link is allowed 1669 * @dir: parent directory 1670 * @dentry: file 1671 * 1672 * Check the permission to remove a hard link to a file. 1673 * 1674 * Return: Returns 0 if permission is granted. 1675 */ 1676 int security_inode_unlink(struct inode *dir, struct dentry *dentry) 1677 { 1678 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 1679 return 0; 1680 return call_int_hook(inode_unlink, dir, dentry); 1681 } 1682 1683 /** 1684 * security_inode_symlink() - Check if creating a symbolic link is allowed 1685 * @dir: parent directory 1686 * @dentry: symbolic link 1687 * @old_name: existing filename 1688 * 1689 * Check the permission to create a symbolic link to a file. 1690 * 1691 * Return: Returns 0 if permission is granted. 1692 */ 1693 int security_inode_symlink(struct inode *dir, struct dentry *dentry, 1694 const char *old_name) 1695 { 1696 if (unlikely(IS_PRIVATE(dir))) 1697 return 0; 1698 return call_int_hook(inode_symlink, dir, dentry, old_name); 1699 } 1700 1701 /** 1702 * security_inode_mkdir() - Check if creating a new directory is allowed 1703 * @dir: parent directory 1704 * @dentry: new directory 1705 * @mode: new directory mode 1706 * 1707 * Check permissions to create a new directory in the existing directory 1708 * associated with inode structure @dir. 1709 * 1710 * Return: Returns 0 if permission is granted. 1711 */ 1712 int security_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) 1713 { 1714 if (unlikely(IS_PRIVATE(dir))) 1715 return 0; 1716 return call_int_hook(inode_mkdir, dir, dentry, mode); 1717 } 1718 EXPORT_SYMBOL_GPL(security_inode_mkdir); 1719 1720 /** 1721 * security_inode_rmdir() - Check if removing a directory is allowed 1722 * @dir: parent directory 1723 * @dentry: directory to be removed 1724 * 1725 * Check the permission to remove a directory. 1726 * 1727 * Return: Returns 0 if permission is granted. 1728 */ 1729 int security_inode_rmdir(struct inode *dir, struct dentry *dentry) 1730 { 1731 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 1732 return 0; 1733 return call_int_hook(inode_rmdir, dir, dentry); 1734 } 1735 1736 /** 1737 * security_inode_mknod() - Check if creating a special file is allowed 1738 * @dir: parent directory 1739 * @dentry: new file 1740 * @mode: new file mode 1741 * @dev: device number 1742 * 1743 * Check permissions when creating a special file (or a socket or a fifo file 1744 * created via the mknod system call). Note that if mknod operation is being 1745 * done for a regular file, then the create hook will be called and not this 1746 * hook. 1747 * 1748 * Return: Returns 0 if permission is granted. 1749 */ 1750 int security_inode_mknod(struct inode *dir, struct dentry *dentry, 1751 umode_t mode, dev_t dev) 1752 { 1753 if (unlikely(IS_PRIVATE(dir))) 1754 return 0; 1755 return call_int_hook(inode_mknod, dir, dentry, mode, dev); 1756 } 1757 1758 /** 1759 * security_inode_rename() - Check if renaming a file is allowed 1760 * @old_dir: parent directory of the old file 1761 * @old_dentry: the old file 1762 * @new_dir: parent directory of the new file 1763 * @new_dentry: the new file 1764 * @flags: flags 1765 * 1766 * Check for permission to rename a file or directory. 1767 * 1768 * Return: Returns 0 if permission is granted. 1769 */ 1770 int security_inode_rename(struct inode *old_dir, struct dentry *old_dentry, 1771 struct inode *new_dir, struct dentry *new_dentry, 1772 unsigned int flags) 1773 { 1774 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) || 1775 (d_is_positive(new_dentry) && 1776 IS_PRIVATE(d_backing_inode(new_dentry))))) 1777 return 0; 1778 1779 if (flags & RENAME_EXCHANGE) { 1780 int err = call_int_hook(inode_rename, new_dir, new_dentry, 1781 old_dir, old_dentry); 1782 if (err) 1783 return err; 1784 } 1785 1786 return call_int_hook(inode_rename, old_dir, old_dentry, 1787 new_dir, new_dentry); 1788 } 1789 1790 /** 1791 * security_inode_readlink() - Check if reading a symbolic link is allowed 1792 * @dentry: link 1793 * 1794 * Check the permission to read the symbolic link. 1795 * 1796 * Return: Returns 0 if permission is granted. 1797 */ 1798 int security_inode_readlink(struct dentry *dentry) 1799 { 1800 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 1801 return 0; 1802 return call_int_hook(inode_readlink, dentry); 1803 } 1804 1805 /** 1806 * security_inode_follow_link() - Check if following a symbolic link is allowed 1807 * @dentry: link dentry 1808 * @inode: link inode 1809 * @rcu: true if in RCU-walk mode 1810 * 1811 * Check permission to follow a symbolic link when looking up a pathname. If 1812 * @rcu is true, @inode is not stable. 1813 * 1814 * Return: Returns 0 if permission is granted. 1815 */ 1816 int security_inode_follow_link(struct dentry *dentry, struct inode *inode, 1817 bool rcu) 1818 { 1819 if (unlikely(IS_PRIVATE(inode))) 1820 return 0; 1821 return call_int_hook(inode_follow_link, dentry, inode, rcu); 1822 } 1823 1824 /** 1825 * security_inode_permission() - Check if accessing an inode is allowed 1826 * @inode: inode 1827 * @mask: access mask 1828 * 1829 * Check permission before accessing an inode. This hook is called by the 1830 * existing Linux permission function, so a security module can use it to 1831 * provide additional checking for existing Linux permission checks. Notice 1832 * that this hook is called when a file is opened (as well as many other 1833 * operations), whereas the file_security_ops permission hook is called when 1834 * the actual read/write operations are performed. 1835 * 1836 * Return: Returns 0 if permission is granted. 1837 */ 1838 int security_inode_permission(struct inode *inode, int mask) 1839 { 1840 if (unlikely(IS_PRIVATE(inode))) 1841 return 0; 1842 return call_int_hook(inode_permission, inode, mask); 1843 } 1844 1845 /** 1846 * security_inode_setattr() - Check if setting file attributes is allowed 1847 * @idmap: idmap of the mount 1848 * @dentry: file 1849 * @attr: new attributes 1850 * 1851 * Check permission before setting file attributes. Note that the kernel call 1852 * to notify_change is performed from several locations, whenever file 1853 * attributes change (such as when a file is truncated, chown/chmod operations, 1854 * transferring disk quotas, etc). 1855 * 1856 * Return: Returns 0 if permission is granted. 1857 */ 1858 int security_inode_setattr(struct mnt_idmap *idmap, 1859 struct dentry *dentry, struct iattr *attr) 1860 { 1861 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 1862 return 0; 1863 return call_int_hook(inode_setattr, idmap, dentry, attr); 1864 } 1865 EXPORT_SYMBOL_GPL(security_inode_setattr); 1866 1867 /** 1868 * security_inode_post_setattr() - Update the inode after a setattr operation 1869 * @idmap: idmap of the mount 1870 * @dentry: file 1871 * @ia_valid: file attributes set 1872 * 1873 * Update inode security field after successful setting file attributes. 1874 */ 1875 void security_inode_post_setattr(struct mnt_idmap *idmap, struct dentry *dentry, 1876 int ia_valid) 1877 { 1878 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 1879 return; 1880 call_void_hook(inode_post_setattr, idmap, dentry, ia_valid); 1881 } 1882 1883 /** 1884 * security_inode_getattr() - Check if getting file attributes is allowed 1885 * @path: file 1886 * 1887 * Check permission before obtaining file attributes. 1888 * 1889 * Return: Returns 0 if permission is granted. 1890 */ 1891 int security_inode_getattr(const struct path *path) 1892 { 1893 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) 1894 return 0; 1895 return call_int_hook(inode_getattr, path); 1896 } 1897 1898 /** 1899 * security_inode_setxattr() - Check if setting file xattrs is allowed 1900 * @idmap: idmap of the mount 1901 * @dentry: file 1902 * @name: xattr name 1903 * @value: xattr value 1904 * @size: size of xattr value 1905 * @flags: flags 1906 * 1907 * This hook performs the desired permission checks before setting the extended 1908 * attributes (xattrs) on @dentry. It is important to note that we have some 1909 * additional logic before the main LSM implementation calls to detect if we 1910 * need to perform an additional capability check at the LSM layer. 1911 * 1912 * Normally we enforce a capability check prior to executing the various LSM 1913 * hook implementations, but if a LSM wants to avoid this capability check, 1914 * it can register a 'inode_xattr_skipcap' hook and return a value of 1 for 1915 * xattrs that it wants to avoid the capability check, leaving the LSM fully 1916 * responsible for enforcing the access control for the specific xattr. If all 1917 * of the enabled LSMs refrain from registering a 'inode_xattr_skipcap' hook, 1918 * or return a 0 (the default return value), the capability check is still 1919 * performed. If no 'inode_xattr_skipcap' hooks are registered the capability 1920 * check is performed. 1921 * 1922 * Return: Returns 0 if permission is granted. 1923 */ 1924 int security_inode_setxattr(struct mnt_idmap *idmap, 1925 struct dentry *dentry, const char *name, 1926 const void *value, size_t size, int flags) 1927 { 1928 int rc; 1929 1930 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 1931 return 0; 1932 1933 /* enforce the capability checks at the lsm layer, if needed */ 1934 if (!call_int_hook(inode_xattr_skipcap, name)) { 1935 rc = cap_inode_setxattr(dentry, name, value, size, flags); 1936 if (rc) 1937 return rc; 1938 } 1939 1940 return call_int_hook(inode_setxattr, idmap, dentry, name, value, size, 1941 flags); 1942 } 1943 1944 /** 1945 * security_inode_set_acl() - Check if setting posix acls is allowed 1946 * @idmap: idmap of the mount 1947 * @dentry: file 1948 * @acl_name: acl name 1949 * @kacl: acl struct 1950 * 1951 * Check permission before setting posix acls, the posix acls in @kacl are 1952 * identified by @acl_name. 1953 * 1954 * Return: Returns 0 if permission is granted. 1955 */ 1956 int security_inode_set_acl(struct mnt_idmap *idmap, 1957 struct dentry *dentry, const char *acl_name, 1958 struct posix_acl *kacl) 1959 { 1960 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 1961 return 0; 1962 return call_int_hook(inode_set_acl, idmap, dentry, acl_name, kacl); 1963 } 1964 1965 /** 1966 * security_inode_post_set_acl() - Update inode security from posix acls set 1967 * @dentry: file 1968 * @acl_name: acl name 1969 * @kacl: acl struct 1970 * 1971 * Update inode security data after successfully setting posix acls on @dentry. 1972 * The posix acls in @kacl are identified by @acl_name. 1973 */ 1974 void security_inode_post_set_acl(struct dentry *dentry, const char *acl_name, 1975 struct posix_acl *kacl) 1976 { 1977 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 1978 return; 1979 call_void_hook(inode_post_set_acl, dentry, acl_name, kacl); 1980 } 1981 1982 /** 1983 * security_inode_get_acl() - Check if reading posix acls is allowed 1984 * @idmap: idmap of the mount 1985 * @dentry: file 1986 * @acl_name: acl name 1987 * 1988 * Check permission before getting osix acls, the posix acls are identified by 1989 * @acl_name. 1990 * 1991 * Return: Returns 0 if permission is granted. 1992 */ 1993 int security_inode_get_acl(struct mnt_idmap *idmap, 1994 struct dentry *dentry, const char *acl_name) 1995 { 1996 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 1997 return 0; 1998 return call_int_hook(inode_get_acl, idmap, dentry, acl_name); 1999 } 2000 2001 /** 2002 * security_inode_remove_acl() - Check if removing a posix acl is allowed 2003 * @idmap: idmap of the mount 2004 * @dentry: file 2005 * @acl_name: acl name 2006 * 2007 * Check permission before removing posix acls, the posix acls are identified 2008 * by @acl_name. 2009 * 2010 * Return: Returns 0 if permission is granted. 2011 */ 2012 int security_inode_remove_acl(struct mnt_idmap *idmap, 2013 struct dentry *dentry, const char *acl_name) 2014 { 2015 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2016 return 0; 2017 return call_int_hook(inode_remove_acl, idmap, dentry, acl_name); 2018 } 2019 2020 /** 2021 * security_inode_post_remove_acl() - Update inode security after rm posix acls 2022 * @idmap: idmap of the mount 2023 * @dentry: file 2024 * @acl_name: acl name 2025 * 2026 * Update inode security data after successfully removing posix acls on 2027 * @dentry in @idmap. The posix acls are identified by @acl_name. 2028 */ 2029 void security_inode_post_remove_acl(struct mnt_idmap *idmap, 2030 struct dentry *dentry, const char *acl_name) 2031 { 2032 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2033 return; 2034 call_void_hook(inode_post_remove_acl, idmap, dentry, acl_name); 2035 } 2036 2037 /** 2038 * security_inode_post_setxattr() - Update the inode after a setxattr operation 2039 * @dentry: file 2040 * @name: xattr name 2041 * @value: xattr value 2042 * @size: xattr value size 2043 * @flags: flags 2044 * 2045 * Update inode security field after successful setxattr operation. 2046 */ 2047 void security_inode_post_setxattr(struct dentry *dentry, const char *name, 2048 const void *value, size_t size, int flags) 2049 { 2050 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2051 return; 2052 call_void_hook(inode_post_setxattr, dentry, name, value, size, flags); 2053 } 2054 2055 /** 2056 * security_inode_getxattr() - Check if xattr access is allowed 2057 * @dentry: file 2058 * @name: xattr name 2059 * 2060 * Check permission before obtaining the extended attributes identified by 2061 * @name for @dentry. 2062 * 2063 * Return: Returns 0 if permission is granted. 2064 */ 2065 int security_inode_getxattr(struct dentry *dentry, const char *name) 2066 { 2067 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2068 return 0; 2069 return call_int_hook(inode_getxattr, dentry, name); 2070 } 2071 2072 /** 2073 * security_inode_listxattr() - Check if listing xattrs is allowed 2074 * @dentry: file 2075 * 2076 * Check permission before obtaining the list of extended attribute names for 2077 * @dentry. 2078 * 2079 * Return: Returns 0 if permission is granted. 2080 */ 2081 int security_inode_listxattr(struct dentry *dentry) 2082 { 2083 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2084 return 0; 2085 return call_int_hook(inode_listxattr, dentry); 2086 } 2087 2088 /** 2089 * security_inode_removexattr() - Check if removing an xattr is allowed 2090 * @idmap: idmap of the mount 2091 * @dentry: file 2092 * @name: xattr name 2093 * 2094 * This hook performs the desired permission checks before setting the extended 2095 * attributes (xattrs) on @dentry. It is important to note that we have some 2096 * additional logic before the main LSM implementation calls to detect if we 2097 * need to perform an additional capability check at the LSM layer. 2098 * 2099 * Normally we enforce a capability check prior to executing the various LSM 2100 * hook implementations, but if a LSM wants to avoid this capability check, 2101 * it can register a 'inode_xattr_skipcap' hook and return a value of 1 for 2102 * xattrs that it wants to avoid the capability check, leaving the LSM fully 2103 * responsible for enforcing the access control for the specific xattr. If all 2104 * of the enabled LSMs refrain from registering a 'inode_xattr_skipcap' hook, 2105 * or return a 0 (the default return value), the capability check is still 2106 * performed. If no 'inode_xattr_skipcap' hooks are registered the capability 2107 * check is performed. 2108 * 2109 * Return: Returns 0 if permission is granted. 2110 */ 2111 int security_inode_removexattr(struct mnt_idmap *idmap, 2112 struct dentry *dentry, const char *name) 2113 { 2114 int rc; 2115 2116 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2117 return 0; 2118 2119 /* enforce the capability checks at the lsm layer, if needed */ 2120 if (!call_int_hook(inode_xattr_skipcap, name)) { 2121 rc = cap_inode_removexattr(idmap, dentry, name); 2122 if (rc) 2123 return rc; 2124 } 2125 2126 return call_int_hook(inode_removexattr, idmap, dentry, name); 2127 } 2128 2129 /** 2130 * security_inode_post_removexattr() - Update the inode after a removexattr op 2131 * @dentry: file 2132 * @name: xattr name 2133 * 2134 * Update the inode after a successful removexattr operation. 2135 */ 2136 void security_inode_post_removexattr(struct dentry *dentry, const char *name) 2137 { 2138 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2139 return; 2140 call_void_hook(inode_post_removexattr, dentry, name); 2141 } 2142 2143 /** 2144 * security_inode_file_setattr() - check if setting fsxattr is allowed 2145 * @dentry: file to set filesystem extended attributes on 2146 * @fa: extended attributes to set on the inode 2147 * 2148 * Called when file_setattr() syscall or FS_IOC_FSSETXATTR ioctl() is called on 2149 * inode 2150 * 2151 * Return: Returns 0 if permission is granted. 2152 */ 2153 int security_inode_file_setattr(struct dentry *dentry, struct file_kattr *fa) 2154 { 2155 return call_int_hook(inode_file_setattr, dentry, fa); 2156 } 2157 2158 /** 2159 * security_inode_file_getattr() - check if retrieving fsxattr is allowed 2160 * @dentry: file to retrieve filesystem extended attributes from 2161 * @fa: extended attributes to get 2162 * 2163 * Called when file_getattr() syscall or FS_IOC_FSGETXATTR ioctl() is called on 2164 * inode 2165 * 2166 * Return: Returns 0 if permission is granted. 2167 */ 2168 int security_inode_file_getattr(struct dentry *dentry, struct file_kattr *fa) 2169 { 2170 return call_int_hook(inode_file_getattr, dentry, fa); 2171 } 2172 2173 /** 2174 * security_inode_need_killpriv() - Check if security_inode_killpriv() required 2175 * @dentry: associated dentry 2176 * 2177 * Called when an inode has been changed to determine if 2178 * security_inode_killpriv() should be called. 2179 * 2180 * Return: Return <0 on error to abort the inode change operation, return 0 if 2181 * security_inode_killpriv() does not need to be called, return >0 if 2182 * security_inode_killpriv() does need to be called. 2183 */ 2184 int security_inode_need_killpriv(struct dentry *dentry) 2185 { 2186 return call_int_hook(inode_need_killpriv, dentry); 2187 } 2188 2189 /** 2190 * security_inode_killpriv() - The setuid bit is removed, update LSM state 2191 * @idmap: idmap of the mount 2192 * @dentry: associated dentry 2193 * 2194 * The @dentry's setuid bit is being removed. Remove similar security labels. 2195 * Called with the dentry->d_inode->i_mutex held. 2196 * 2197 * Return: Return 0 on success. If error is returned, then the operation 2198 * causing setuid bit removal is failed. 2199 */ 2200 int security_inode_killpriv(struct mnt_idmap *idmap, 2201 struct dentry *dentry) 2202 { 2203 return call_int_hook(inode_killpriv, idmap, dentry); 2204 } 2205 2206 /** 2207 * security_inode_getsecurity() - Get the xattr security label of an inode 2208 * @idmap: idmap of the mount 2209 * @inode: inode 2210 * @name: xattr name 2211 * @buffer: security label buffer 2212 * @alloc: allocation flag 2213 * 2214 * Retrieve a copy of the extended attribute representation of the security 2215 * label associated with @name for @inode via @buffer. Note that @name is the 2216 * remainder of the attribute name after the security prefix has been removed. 2217 * @alloc is used to specify if the call should return a value via the buffer 2218 * or just the value length. 2219 * 2220 * Return: Returns size of buffer on success. 2221 */ 2222 int security_inode_getsecurity(struct mnt_idmap *idmap, 2223 struct inode *inode, const char *name, 2224 void **buffer, bool alloc) 2225 { 2226 if (unlikely(IS_PRIVATE(inode))) 2227 return LSM_RET_DEFAULT(inode_getsecurity); 2228 2229 return call_int_hook(inode_getsecurity, idmap, inode, name, buffer, 2230 alloc); 2231 } 2232 2233 /** 2234 * security_inode_setsecurity() - Set the xattr security label of an inode 2235 * @inode: inode 2236 * @name: xattr name 2237 * @value: security label 2238 * @size: length of security label 2239 * @flags: flags 2240 * 2241 * Set the security label associated with @name for @inode from the extended 2242 * attribute value @value. @size indicates the size of the @value in bytes. 2243 * @flags may be XATTR_CREATE, XATTR_REPLACE, or 0. Note that @name is the 2244 * remainder of the attribute name after the security. prefix has been removed. 2245 * 2246 * Return: Returns 0 on success. 2247 */ 2248 int security_inode_setsecurity(struct inode *inode, const char *name, 2249 const void *value, size_t size, int flags) 2250 { 2251 if (unlikely(IS_PRIVATE(inode))) 2252 return LSM_RET_DEFAULT(inode_setsecurity); 2253 2254 return call_int_hook(inode_setsecurity, inode, name, value, size, 2255 flags); 2256 } 2257 2258 /** 2259 * security_inode_listsecurity() - List the xattr security label names 2260 * @inode: inode 2261 * @buffer: pointer to buffer 2262 * @remaining_size: pointer to remaining size of buffer 2263 * 2264 * Copy the extended attribute names for the security labels associated with 2265 * @inode into *(@buffer). The remaining size of @buffer is specified by 2266 * *(@remaining_size). *(@buffer) may be NULL to request the size of the 2267 * buffer required. Updates *(@buffer) and *(@remaining_size). 2268 * 2269 * Return: Returns 0 on success, or -errno on failure. 2270 */ 2271 int security_inode_listsecurity(struct inode *inode, 2272 char **buffer, ssize_t *remaining_size) 2273 { 2274 if (unlikely(IS_PRIVATE(inode))) 2275 return 0; 2276 return call_int_hook(inode_listsecurity, inode, buffer, remaining_size); 2277 } 2278 EXPORT_SYMBOL(security_inode_listsecurity); 2279 2280 /** 2281 * security_inode_getlsmprop() - Get an inode's LSM data 2282 * @inode: inode 2283 * @prop: lsm specific information to return 2284 * 2285 * Get the lsm specific information associated with the node. 2286 */ 2287 void security_inode_getlsmprop(struct inode *inode, struct lsm_prop *prop) 2288 { 2289 call_void_hook(inode_getlsmprop, inode, prop); 2290 } 2291 2292 /** 2293 * security_inode_copy_up() - Create new creds for an overlayfs copy-up op 2294 * @src: union dentry of copy-up file 2295 * @new: newly created creds 2296 * 2297 * A file is about to be copied up from lower layer to upper layer of overlay 2298 * filesystem. Security module can prepare a set of new creds and modify as 2299 * need be and return new creds. Caller will switch to new creds temporarily to 2300 * create new file and release newly allocated creds. 2301 * 2302 * Return: Returns 0 on success or a negative error code on error. 2303 */ 2304 int security_inode_copy_up(struct dentry *src, struct cred **new) 2305 { 2306 return call_int_hook(inode_copy_up, src, new); 2307 } 2308 EXPORT_SYMBOL(security_inode_copy_up); 2309 2310 /** 2311 * security_inode_copy_up_xattr() - Filter xattrs in an overlayfs copy-up op 2312 * @src: union dentry of copy-up file 2313 * @name: xattr name 2314 * 2315 * Filter the xattrs being copied up when a unioned file is copied up from a 2316 * lower layer to the union/overlay layer. The caller is responsible for 2317 * reading and writing the xattrs, this hook is merely a filter. 2318 * 2319 * Return: Returns 0 to accept the xattr, -ECANCELED to discard the xattr, 2320 * -EOPNOTSUPP if the security module does not know about attribute, 2321 * or a negative error code to abort the copy up. 2322 */ 2323 int security_inode_copy_up_xattr(struct dentry *src, const char *name) 2324 { 2325 int rc; 2326 2327 rc = call_int_hook(inode_copy_up_xattr, src, name); 2328 if (rc != LSM_RET_DEFAULT(inode_copy_up_xattr)) 2329 return rc; 2330 2331 return LSM_RET_DEFAULT(inode_copy_up_xattr); 2332 } 2333 EXPORT_SYMBOL(security_inode_copy_up_xattr); 2334 2335 /** 2336 * security_inode_setintegrity() - Set the inode's integrity data 2337 * @inode: inode 2338 * @type: type of integrity, e.g. hash digest, signature, etc 2339 * @value: the integrity value 2340 * @size: size of the integrity value 2341 * 2342 * Register a verified integrity measurement of a inode with LSMs. 2343 * LSMs should free the previously saved data if @value is NULL. 2344 * 2345 * Return: Returns 0 on success, negative values on failure. 2346 */ 2347 int security_inode_setintegrity(const struct inode *inode, 2348 enum lsm_integrity_type type, const void *value, 2349 size_t size) 2350 { 2351 return call_int_hook(inode_setintegrity, inode, type, value, size); 2352 } 2353 EXPORT_SYMBOL(security_inode_setintegrity); 2354 2355 /** 2356 * security_kernfs_init_security() - Init LSM context for a kernfs node 2357 * @kn_dir: parent kernfs node 2358 * @kn: the kernfs node to initialize 2359 * 2360 * Initialize the security context of a newly created kernfs node based on its 2361 * own and its parent's attributes. 2362 * 2363 * Return: Returns 0 if permission is granted. 2364 */ 2365 int security_kernfs_init_security(struct kernfs_node *kn_dir, 2366 struct kernfs_node *kn) 2367 { 2368 return call_int_hook(kernfs_init_security, kn_dir, kn); 2369 } 2370 2371 /** 2372 * security_file_permission() - Check file permissions 2373 * @file: file 2374 * @mask: requested permissions 2375 * 2376 * Check file permissions before accessing an open file. This hook is called 2377 * by various operations that read or write files. A security module can use 2378 * this hook to perform additional checking on these operations, e.g. to 2379 * revalidate permissions on use to support privilege bracketing or policy 2380 * changes. Notice that this hook is used when the actual read/write 2381 * operations are performed, whereas the inode_security_ops hook is called when 2382 * a file is opened (as well as many other operations). Although this hook can 2383 * be used to revalidate permissions for various system call operations that 2384 * read or write files, it does not address the revalidation of permissions for 2385 * memory-mapped files. Security modules must handle this separately if they 2386 * need such revalidation. 2387 * 2388 * Return: Returns 0 if permission is granted. 2389 */ 2390 int security_file_permission(struct file *file, int mask) 2391 { 2392 return call_int_hook(file_permission, file, mask); 2393 } 2394 2395 /** 2396 * security_file_alloc() - Allocate and init a file's LSM blob 2397 * @file: the file 2398 * 2399 * Allocate and attach a security structure to the file->f_security field. The 2400 * security field is initialized to NULL when the structure is first created. 2401 * 2402 * Return: Return 0 if the hook is successful and permission is granted. 2403 */ 2404 int security_file_alloc(struct file *file) 2405 { 2406 int rc = lsm_file_alloc(file); 2407 2408 if (rc) 2409 return rc; 2410 rc = call_int_hook(file_alloc_security, file); 2411 if (unlikely(rc)) 2412 security_file_free(file); 2413 return rc; 2414 } 2415 2416 /** 2417 * security_file_release() - Perform actions before releasing the file ref 2418 * @file: the file 2419 * 2420 * Perform actions before releasing the last reference to a file. 2421 */ 2422 void security_file_release(struct file *file) 2423 { 2424 call_void_hook(file_release, file); 2425 } 2426 2427 /** 2428 * security_file_free() - Free a file's LSM blob 2429 * @file: the file 2430 * 2431 * Deallocate and free any security structures stored in file->f_security. 2432 */ 2433 void security_file_free(struct file *file) 2434 { 2435 void *blob; 2436 2437 call_void_hook(file_free_security, file); 2438 2439 blob = file->f_security; 2440 if (blob) { 2441 file->f_security = NULL; 2442 kmem_cache_free(lsm_file_cache, blob); 2443 } 2444 } 2445 2446 /** 2447 * security_backing_file_alloc() - Allocate and setup a backing file blob 2448 * @backing_file: the backing file 2449 * @user_file: the associated user visible file 2450 * 2451 * Allocate a backing file LSM blob and perform any necessary initialization of 2452 * the LSM blob. There will be some operations where the LSM will not have 2453 * access to @user_file after this point, so any important state associated 2454 * with @user_file that is important to the LSM should be captured in the 2455 * backing file's LSM blob. 2456 * 2457 * LSM's should avoid taking a reference to @user_file in this hook as it will 2458 * result in problems later when the system attempts to drop/put the file 2459 * references due to a circular dependency. 2460 * 2461 * Return: Return 0 if the hook is successful, negative values otherwise. 2462 */ 2463 int security_backing_file_alloc(struct file *backing_file, 2464 const struct file *user_file) 2465 { 2466 int rc; 2467 2468 rc = lsm_backing_file_alloc(backing_file); 2469 if (rc) 2470 return rc; 2471 rc = call_int_hook(backing_file_alloc, backing_file, user_file); 2472 if (unlikely(rc)) 2473 security_backing_file_free(backing_file); 2474 2475 return rc; 2476 } 2477 2478 /** 2479 * security_backing_file_free() - Free a backing file blob 2480 * @backing_file: the backing file 2481 * 2482 * Free any LSM state associate with a backing file's LSM blob, including the 2483 * blob itself. 2484 */ 2485 void security_backing_file_free(struct file *backing_file) 2486 { 2487 void *blob = backing_file_security(backing_file); 2488 2489 call_void_hook(backing_file_free, backing_file); 2490 2491 if (blob) { 2492 backing_file_set_security(backing_file, NULL); 2493 kmem_cache_free(lsm_backing_file_cache, blob); 2494 } 2495 } 2496 2497 /** 2498 * security_file_ioctl() - Check if an ioctl is allowed 2499 * @file: associated file 2500 * @cmd: ioctl cmd 2501 * @arg: ioctl arguments 2502 * 2503 * Check permission for an ioctl operation on @file. Note that @arg sometimes 2504 * represents a user space pointer; in other cases, it may be a simple integer 2505 * value. When @arg represents a user space pointer, it should never be used 2506 * by the security module. 2507 * 2508 * Return: Returns 0 if permission is granted. 2509 */ 2510 int security_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 2511 { 2512 return call_int_hook(file_ioctl, file, cmd, arg); 2513 } 2514 EXPORT_SYMBOL_GPL(security_file_ioctl); 2515 2516 /** 2517 * security_file_ioctl_compat() - Check if an ioctl is allowed in compat mode 2518 * @file: associated file 2519 * @cmd: ioctl cmd 2520 * @arg: ioctl arguments 2521 * 2522 * Compat version of security_file_ioctl() that correctly handles 32-bit 2523 * processes running on 64-bit kernels. 2524 * 2525 * Return: Returns 0 if permission is granted. 2526 */ 2527 int security_file_ioctl_compat(struct file *file, unsigned int cmd, 2528 unsigned long arg) 2529 { 2530 return call_int_hook(file_ioctl_compat, file, cmd, arg); 2531 } 2532 EXPORT_SYMBOL_GPL(security_file_ioctl_compat); 2533 2534 static inline unsigned long mmap_prot(struct file *file, unsigned long prot) 2535 { 2536 /* 2537 * Does we have PROT_READ and does the application expect 2538 * it to imply PROT_EXEC? If not, nothing to talk about... 2539 */ 2540 if ((prot & (PROT_READ | PROT_EXEC)) != PROT_READ) 2541 return prot; 2542 if (!(current->personality & READ_IMPLIES_EXEC)) 2543 return prot; 2544 /* 2545 * if that's an anonymous mapping, let it. 2546 */ 2547 if (!file) 2548 return prot | PROT_EXEC; 2549 /* 2550 * ditto if it's not on noexec mount, except that on !MMU we need 2551 * NOMMU_MAP_EXEC (== VM_MAYEXEC) in this case 2552 */ 2553 if (!path_noexec(&file->f_path)) { 2554 #ifndef CONFIG_MMU 2555 if (file->f_op->mmap_capabilities) { 2556 unsigned caps = file->f_op->mmap_capabilities(file); 2557 if (!(caps & NOMMU_MAP_EXEC)) 2558 return prot; 2559 } 2560 #endif 2561 return prot | PROT_EXEC; 2562 } 2563 /* anything on noexec mount won't get PROT_EXEC */ 2564 return prot; 2565 } 2566 2567 /** 2568 * security_mmap_file() - Check if mmap'ing a file is allowed 2569 * @file: file 2570 * @prot: protection applied by the kernel 2571 * @flags: flags 2572 * 2573 * Check permissions for a mmap operation. The @file may be NULL, e.g. if 2574 * mapping anonymous memory. 2575 * 2576 * Return: Returns 0 if permission is granted. 2577 */ 2578 int security_mmap_file(struct file *file, unsigned long prot, 2579 unsigned long flags) 2580 { 2581 return call_int_hook(mmap_file, file, prot, mmap_prot(file, prot), 2582 flags); 2583 } 2584 2585 /** 2586 * security_mmap_backing_file - Check if mmap'ing a backing file is allowed 2587 * @vma: the vm_area_struct for the mmap'd region 2588 * @backing_file: the backing file being mmap'd 2589 * @user_file: the user file being mmap'd 2590 * 2591 * Check permissions for a mmap operation on a stacked filesystem. This hook 2592 * is called after the security_mmap_file() and is responsible for authorizing 2593 * the mmap on @backing_file. It is important to note that the mmap operation 2594 * on @user_file has already been authorized and the @vma->vm_file has been 2595 * set to @backing_file. 2596 * 2597 * Return: Returns 0 if permission is granted. 2598 */ 2599 int security_mmap_backing_file(struct vm_area_struct *vma, 2600 struct file *backing_file, 2601 struct file *user_file) 2602 { 2603 /* recommended by the stackable filesystem devs */ 2604 if (WARN_ON_ONCE(!(backing_file->f_mode & FMODE_BACKING))) 2605 return -EIO; 2606 2607 return call_int_hook(mmap_backing_file, vma, backing_file, user_file); 2608 } 2609 EXPORT_SYMBOL_GPL(security_mmap_backing_file); 2610 2611 /** 2612 * security_mmap_addr() - Check if mmap'ing an address is allowed 2613 * @addr: address 2614 * 2615 * Check permissions for a mmap operation at @addr. 2616 * 2617 * Return: Returns 0 if permission is granted. 2618 */ 2619 int security_mmap_addr(unsigned long addr) 2620 { 2621 return call_int_hook(mmap_addr, addr); 2622 } 2623 2624 /** 2625 * security_file_mprotect() - Check if changing memory protections is allowed 2626 * @vma: memory region 2627 * @reqprot: application requested protection 2628 * @prot: protection applied by the kernel 2629 * 2630 * Check permissions before changing memory access permissions. 2631 * 2632 * Return: Returns 0 if permission is granted. 2633 */ 2634 int security_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot, 2635 unsigned long prot) 2636 { 2637 return call_int_hook(file_mprotect, vma, reqprot, prot); 2638 } 2639 2640 /** 2641 * security_file_lock() - Check if a file lock is allowed 2642 * @file: file 2643 * @cmd: lock operation (e.g. F_RDLCK, F_WRLCK) 2644 * 2645 * Check permission before performing file locking operations. Note the hook 2646 * mediates both flock and fcntl style locks. 2647 * 2648 * Return: Returns 0 if permission is granted. 2649 */ 2650 int security_file_lock(struct file *file, unsigned int cmd) 2651 { 2652 return call_int_hook(file_lock, file, cmd); 2653 } 2654 2655 /** 2656 * security_file_fcntl() - Check if fcntl() op is allowed 2657 * @file: file 2658 * @cmd: fcntl command 2659 * @arg: command argument 2660 * 2661 * Check permission before allowing the file operation specified by @cmd from 2662 * being performed on the file @file. Note that @arg sometimes represents a 2663 * user space pointer; in other cases, it may be a simple integer value. When 2664 * @arg represents a user space pointer, it should never be used by the 2665 * security module. 2666 * 2667 * Return: Returns 0 if permission is granted. 2668 */ 2669 int security_file_fcntl(struct file *file, unsigned int cmd, unsigned long arg) 2670 { 2671 return call_int_hook(file_fcntl, file, cmd, arg); 2672 } 2673 2674 /** 2675 * security_file_set_fowner() - Set the file owner info in the LSM blob 2676 * @file: the file 2677 * 2678 * Save owner security information (typically from current->security) in 2679 * file->f_security for later use by the send_sigiotask hook. 2680 * 2681 * This hook is called with file->f_owner.lock held. 2682 * 2683 * Return: Returns 0 on success. 2684 */ 2685 void security_file_set_fowner(struct file *file) 2686 { 2687 call_void_hook(file_set_fowner, file); 2688 } 2689 2690 /** 2691 * security_file_send_sigiotask() - Check if sending SIGIO/SIGURG is allowed 2692 * @tsk: target task 2693 * @fown: signal sender 2694 * @sig: signal to be sent, SIGIO is sent if 0 2695 * 2696 * Check permission for the file owner @fown to send SIGIO or SIGURG to the 2697 * process @tsk. Note that this hook is sometimes called from interrupt. Note 2698 * that the fown_struct, @fown, is never outside the context of a struct file, 2699 * so the file structure (and associated security information) can always be 2700 * obtained: container_of(fown, struct file, f_owner). 2701 * 2702 * Return: Returns 0 if permission is granted. 2703 */ 2704 int security_file_send_sigiotask(struct task_struct *tsk, 2705 struct fown_struct *fown, int sig) 2706 { 2707 return call_int_hook(file_send_sigiotask, tsk, fown, sig); 2708 } 2709 2710 /** 2711 * security_file_receive() - Check if receiving a file via IPC is allowed 2712 * @file: file being received 2713 * 2714 * This hook allows security modules to control the ability of a process to 2715 * receive an open file descriptor via socket IPC. 2716 * 2717 * Return: Returns 0 if permission is granted. 2718 */ 2719 int security_file_receive(struct file *file) 2720 { 2721 return call_int_hook(file_receive, file); 2722 } 2723 2724 /** 2725 * security_file_open() - Save open() time state for late use by the LSM 2726 * @file: 2727 * 2728 * Save open-time permission checking state for later use upon file_permission, 2729 * and recheck access if anything has changed since inode_permission. 2730 * 2731 * We can check if a file is opened for execution (e.g. execve(2) call), either 2732 * directly or indirectly (e.g. ELF's ld.so) by checking file->f_flags & 2733 * __FMODE_EXEC . 2734 * 2735 * Return: Returns 0 if permission is granted. 2736 */ 2737 int security_file_open(struct file *file) 2738 { 2739 return call_int_hook(file_open, file); 2740 } 2741 2742 /** 2743 * security_file_post_open() - Evaluate a file after it has been opened 2744 * @file: the file 2745 * @mask: access mask 2746 * 2747 * Evaluate an opened file and the access mask requested with open(). The hook 2748 * is useful for LSMs that require the file content to be available in order to 2749 * make decisions. 2750 * 2751 * Return: Returns 0 if permission is granted. 2752 */ 2753 int security_file_post_open(struct file *file, int mask) 2754 { 2755 return call_int_hook(file_post_open, file, mask); 2756 } 2757 EXPORT_SYMBOL_GPL(security_file_post_open); 2758 2759 /** 2760 * security_file_truncate() - Check if truncating a file is allowed 2761 * @file: file 2762 * 2763 * Check permission before truncating a file, i.e. using ftruncate. Note that 2764 * truncation permission may also be checked based on the path, using the 2765 * @path_truncate hook. 2766 * 2767 * Return: Returns 0 if permission is granted. 2768 */ 2769 int security_file_truncate(struct file *file) 2770 { 2771 return call_int_hook(file_truncate, file); 2772 } 2773 2774 /** 2775 * security_task_alloc() - Allocate a task's LSM blob 2776 * @task: the task 2777 * @clone_flags: flags indicating what is being shared 2778 * 2779 * Handle allocation of task-related resources. 2780 * 2781 * Return: Returns a zero on success, negative values on failure. 2782 */ 2783 int security_task_alloc(struct task_struct *task, u64 clone_flags) 2784 { 2785 int rc = lsm_task_alloc(task); 2786 2787 if (rc) 2788 return rc; 2789 rc = call_int_hook(task_alloc, task, clone_flags); 2790 if (unlikely(rc)) 2791 security_task_free(task); 2792 return rc; 2793 } 2794 2795 /** 2796 * security_task_free() - Free a task's LSM blob and related resources 2797 * @task: task 2798 * 2799 * Handle release of task-related resources. Note that this can be called from 2800 * interrupt context. 2801 */ 2802 void security_task_free(struct task_struct *task) 2803 { 2804 call_void_hook(task_free, task); 2805 2806 kfree(task->security); 2807 task->security = NULL; 2808 } 2809 2810 /** 2811 * security_cred_alloc_blank() - Allocate the min memory to allow cred_transfer 2812 * @cred: credentials 2813 * @gfp: gfp flags 2814 * 2815 * Only allocate sufficient memory and attach to @cred such that 2816 * cred_transfer() will not get ENOMEM. 2817 * 2818 * Return: Returns 0 on success, negative values on failure. 2819 */ 2820 int security_cred_alloc_blank(struct cred *cred, gfp_t gfp) 2821 { 2822 int rc = lsm_cred_alloc(cred, gfp); 2823 2824 if (rc) 2825 return rc; 2826 2827 rc = call_int_hook(cred_alloc_blank, cred, gfp); 2828 if (unlikely(rc)) 2829 security_cred_free(cred); 2830 return rc; 2831 } 2832 2833 /** 2834 * security_cred_free() - Free the cred's LSM blob and associated resources 2835 * @cred: credentials 2836 * 2837 * Deallocate and clear the cred->security field in a set of credentials. 2838 */ 2839 void security_cred_free(struct cred *cred) 2840 { 2841 /* 2842 * There is a failure case in prepare_creds() that 2843 * may result in a call here with ->security being NULL. 2844 */ 2845 if (unlikely(cred->security == NULL)) 2846 return; 2847 2848 call_void_hook(cred_free, cred); 2849 2850 kfree(cred->security); 2851 cred->security = NULL; 2852 } 2853 2854 /** 2855 * security_prepare_creds() - Prepare a new set of credentials 2856 * @new: new credentials 2857 * @old: original credentials 2858 * @gfp: gfp flags 2859 * 2860 * Prepare a new set of credentials by copying the data from the old set. 2861 * 2862 * Return: Returns 0 on success, negative values on failure. 2863 */ 2864 int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp) 2865 { 2866 int rc = lsm_cred_alloc(new, gfp); 2867 2868 if (rc) 2869 return rc; 2870 2871 rc = call_int_hook(cred_prepare, new, old, gfp); 2872 if (unlikely(rc)) 2873 security_cred_free(new); 2874 return rc; 2875 } 2876 2877 /** 2878 * security_transfer_creds() - Transfer creds 2879 * @new: target credentials 2880 * @old: original credentials 2881 * 2882 * Transfer data from original creds to new creds. 2883 */ 2884 void security_transfer_creds(struct cred *new, const struct cred *old) 2885 { 2886 call_void_hook(cred_transfer, new, old); 2887 } 2888 2889 /** 2890 * security_cred_getsecid() - Get the secid from a set of credentials 2891 * @c: credentials 2892 * @secid: secid value 2893 * 2894 * Retrieve the security identifier of the cred structure @c. In case of 2895 * failure, @secid will be set to zero. 2896 */ 2897 void security_cred_getsecid(const struct cred *c, u32 *secid) 2898 { 2899 *secid = 0; 2900 call_void_hook(cred_getsecid, c, secid); 2901 } 2902 EXPORT_SYMBOL(security_cred_getsecid); 2903 2904 /** 2905 * security_cred_getlsmprop() - Get the LSM data from a set of credentials 2906 * @c: credentials 2907 * @prop: destination for the LSM data 2908 * 2909 * Retrieve the security data of the cred structure @c. In case of 2910 * failure, @prop will be cleared. 2911 */ 2912 void security_cred_getlsmprop(const struct cred *c, struct lsm_prop *prop) 2913 { 2914 lsmprop_init(prop); 2915 call_void_hook(cred_getlsmprop, c, prop); 2916 } 2917 EXPORT_SYMBOL(security_cred_getlsmprop); 2918 2919 /** 2920 * security_kernel_act_as() - Set the kernel credentials to act as secid 2921 * @new: credentials 2922 * @secid: secid 2923 * 2924 * Set the credentials for a kernel service to act as (subjective context). 2925 * The current task must be the one that nominated @secid. 2926 * 2927 * Return: Returns 0 if successful. 2928 */ 2929 int security_kernel_act_as(struct cred *new, u32 secid) 2930 { 2931 return call_int_hook(kernel_act_as, new, secid); 2932 } 2933 2934 /** 2935 * security_kernel_create_files_as() - Set file creation context using an inode 2936 * @new: target credentials 2937 * @inode: reference inode 2938 * 2939 * Set the file creation context in a set of credentials to be the same as the 2940 * objective context of the specified inode. The current task must be the one 2941 * that nominated @inode. 2942 * 2943 * Return: Returns 0 if successful. 2944 */ 2945 int security_kernel_create_files_as(struct cred *new, struct inode *inode) 2946 { 2947 return call_int_hook(kernel_create_files_as, new, inode); 2948 } 2949 2950 /** 2951 * security_kernel_module_request() - Check if loading a module is allowed 2952 * @kmod_name: module name 2953 * 2954 * Ability to trigger the kernel to automatically upcall to userspace for 2955 * userspace to load a kernel module with the given name. 2956 * 2957 * Return: Returns 0 if successful. 2958 */ 2959 int security_kernel_module_request(char *kmod_name) 2960 { 2961 return call_int_hook(kernel_module_request, kmod_name); 2962 } 2963 2964 /** 2965 * security_kernel_read_file() - Read a file specified by userspace 2966 * @file: file 2967 * @id: file identifier 2968 * @contents: trust if security_kernel_post_read_file() will be called 2969 * 2970 * Read a file specified by userspace. 2971 * 2972 * Return: Returns 0 if permission is granted. 2973 */ 2974 int security_kernel_read_file(struct file *file, enum kernel_read_file_id id, 2975 bool contents) 2976 { 2977 return call_int_hook(kernel_read_file, file, id, contents); 2978 } 2979 EXPORT_SYMBOL_GPL(security_kernel_read_file); 2980 2981 /** 2982 * security_kernel_post_read_file() - Read a file specified by userspace 2983 * @file: file 2984 * @buf: file contents 2985 * @size: size of file contents 2986 * @id: file identifier 2987 * 2988 * Read a file specified by userspace. This must be paired with a prior call 2989 * to security_kernel_read_file() call that indicated this hook would also be 2990 * called, see security_kernel_read_file() for more information. 2991 * 2992 * Return: Returns 0 if permission is granted. 2993 */ 2994 int security_kernel_post_read_file(struct file *file, char *buf, loff_t size, 2995 enum kernel_read_file_id id) 2996 { 2997 return call_int_hook(kernel_post_read_file, file, buf, size, id); 2998 } 2999 EXPORT_SYMBOL_GPL(security_kernel_post_read_file); 3000 3001 /** 3002 * security_kernel_load_data() - Load data provided by userspace 3003 * @id: data identifier 3004 * @contents: true if security_kernel_post_load_data() will be called 3005 * 3006 * Load data provided by userspace. 3007 * 3008 * Return: Returns 0 if permission is granted. 3009 */ 3010 int security_kernel_load_data(enum kernel_load_data_id id, bool contents) 3011 { 3012 return call_int_hook(kernel_load_data, id, contents); 3013 } 3014 EXPORT_SYMBOL_GPL(security_kernel_load_data); 3015 3016 /** 3017 * security_kernel_post_load_data() - Load userspace data from a non-file source 3018 * @buf: data 3019 * @size: size of data 3020 * @id: data identifier 3021 * @description: text description of data, specific to the id value 3022 * 3023 * Load data provided by a non-file source (usually userspace buffer). This 3024 * must be paired with a prior security_kernel_load_data() call that indicated 3025 * this hook would also be called, see security_kernel_load_data() for more 3026 * information. 3027 * 3028 * Return: Returns 0 if permission is granted. 3029 */ 3030 int security_kernel_post_load_data(char *buf, loff_t size, 3031 enum kernel_load_data_id id, 3032 char *description) 3033 { 3034 return call_int_hook(kernel_post_load_data, buf, size, id, description); 3035 } 3036 EXPORT_SYMBOL_GPL(security_kernel_post_load_data); 3037 3038 /** 3039 * security_task_fix_setuid() - Update LSM with new user id attributes 3040 * @new: updated credentials 3041 * @old: credentials being replaced 3042 * @flags: LSM_SETID_* flag values 3043 * 3044 * Update the module's state after setting one or more of the user identity 3045 * attributes of the current process. The @flags parameter indicates which of 3046 * the set*uid system calls invoked this hook. If @new is the set of 3047 * credentials that will be installed. Modifications should be made to this 3048 * rather than to @current->cred. 3049 * 3050 * Return: Returns 0 on success. 3051 */ 3052 int security_task_fix_setuid(struct cred *new, const struct cred *old, 3053 int flags) 3054 { 3055 return call_int_hook(task_fix_setuid, new, old, flags); 3056 } 3057 3058 /** 3059 * security_task_fix_setgid() - Update LSM with new group id attributes 3060 * @new: updated credentials 3061 * @old: credentials being replaced 3062 * @flags: LSM_SETID_* flag value 3063 * 3064 * Update the module's state after setting one or more of the group identity 3065 * attributes of the current process. The @flags parameter indicates which of 3066 * the set*gid system calls invoked this hook. @new is the set of credentials 3067 * that will be installed. Modifications should be made to this rather than to 3068 * @current->cred. 3069 * 3070 * Return: Returns 0 on success. 3071 */ 3072 int security_task_fix_setgid(struct cred *new, const struct cred *old, 3073 int flags) 3074 { 3075 return call_int_hook(task_fix_setgid, new, old, flags); 3076 } 3077 3078 /** 3079 * security_task_fix_setgroups() - Update LSM with new supplementary groups 3080 * @new: updated credentials 3081 * @old: credentials being replaced 3082 * 3083 * Update the module's state after setting the supplementary group identity 3084 * attributes of the current process. @new is the set of credentials that will 3085 * be installed. Modifications should be made to this rather than to 3086 * @current->cred. 3087 * 3088 * Return: Returns 0 on success. 3089 */ 3090 int security_task_fix_setgroups(struct cred *new, const struct cred *old) 3091 { 3092 return call_int_hook(task_fix_setgroups, new, old); 3093 } 3094 3095 /** 3096 * security_task_setpgid() - Check if setting the pgid is allowed 3097 * @p: task being modified 3098 * @pgid: new pgid 3099 * 3100 * Check permission before setting the process group identifier of the process 3101 * @p to @pgid. 3102 * 3103 * Return: Returns 0 if permission is granted. 3104 */ 3105 int security_task_setpgid(struct task_struct *p, pid_t pgid) 3106 { 3107 return call_int_hook(task_setpgid, p, pgid); 3108 } 3109 3110 /** 3111 * security_task_getpgid() - Check if getting the pgid is allowed 3112 * @p: task 3113 * 3114 * Check permission before getting the process group identifier of the process 3115 * @p. 3116 * 3117 * Return: Returns 0 if permission is granted. 3118 */ 3119 int security_task_getpgid(struct task_struct *p) 3120 { 3121 return call_int_hook(task_getpgid, p); 3122 } 3123 3124 /** 3125 * security_task_getsid() - Check if getting the session id is allowed 3126 * @p: task 3127 * 3128 * Check permission before getting the session identifier of the process @p. 3129 * 3130 * Return: Returns 0 if permission is granted. 3131 */ 3132 int security_task_getsid(struct task_struct *p) 3133 { 3134 return call_int_hook(task_getsid, p); 3135 } 3136 3137 /** 3138 * security_current_getlsmprop_subj() - Current task's subjective LSM data 3139 * @prop: lsm specific information 3140 * 3141 * Retrieve the subjective security identifier of the current task and return 3142 * it in @prop. 3143 */ 3144 void security_current_getlsmprop_subj(struct lsm_prop *prop) 3145 { 3146 lsmprop_init(prop); 3147 call_void_hook(current_getlsmprop_subj, prop); 3148 } 3149 EXPORT_SYMBOL(security_current_getlsmprop_subj); 3150 3151 /** 3152 * security_task_getlsmprop_obj() - Get a task's objective LSM data 3153 * @p: target task 3154 * @prop: lsm specific information 3155 * 3156 * Retrieve the objective security identifier of the task_struct in @p and 3157 * return it in @prop. 3158 */ 3159 void security_task_getlsmprop_obj(struct task_struct *p, struct lsm_prop *prop) 3160 { 3161 lsmprop_init(prop); 3162 call_void_hook(task_getlsmprop_obj, p, prop); 3163 } 3164 EXPORT_SYMBOL(security_task_getlsmprop_obj); 3165 3166 /** 3167 * security_task_setnice() - Check if setting a task's nice value is allowed 3168 * @p: target task 3169 * @nice: nice value 3170 * 3171 * Check permission before setting the nice value of @p to @nice. 3172 * 3173 * Return: Returns 0 if permission is granted. 3174 */ 3175 int security_task_setnice(struct task_struct *p, int nice) 3176 { 3177 return call_int_hook(task_setnice, p, nice); 3178 } 3179 3180 /** 3181 * security_task_setioprio() - Check if setting a task's ioprio is allowed 3182 * @p: target task 3183 * @ioprio: ioprio value 3184 * 3185 * Check permission before setting the ioprio value of @p to @ioprio. 3186 * 3187 * Return: Returns 0 if permission is granted. 3188 */ 3189 int security_task_setioprio(struct task_struct *p, int ioprio) 3190 { 3191 return call_int_hook(task_setioprio, p, ioprio); 3192 } 3193 3194 /** 3195 * security_task_getioprio() - Check if getting a task's ioprio is allowed 3196 * @p: task 3197 * 3198 * Check permission before getting the ioprio value of @p. 3199 * 3200 * Return: Returns 0 if permission is granted. 3201 */ 3202 int security_task_getioprio(struct task_struct *p) 3203 { 3204 return call_int_hook(task_getioprio, p); 3205 } 3206 3207 /** 3208 * security_task_prlimit() - Check if get/setting resources limits is allowed 3209 * @cred: current task credentials 3210 * @tcred: target task credentials 3211 * @flags: LSM_PRLIMIT_* flag bits indicating a get/set/both 3212 * 3213 * Check permission before getting and/or setting the resource limits of 3214 * another task. 3215 * 3216 * Return: Returns 0 if permission is granted. 3217 */ 3218 int security_task_prlimit(const struct cred *cred, const struct cred *tcred, 3219 unsigned int flags) 3220 { 3221 return call_int_hook(task_prlimit, cred, tcred, flags); 3222 } 3223 3224 /** 3225 * security_task_setrlimit() - Check if setting a new rlimit value is allowed 3226 * @p: target task's group leader 3227 * @resource: resource whose limit is being set 3228 * @new_rlim: new resource limit 3229 * 3230 * Check permission before setting the resource limits of process @p for 3231 * @resource to @new_rlim. The old resource limit values can be examined by 3232 * dereferencing (p->signal->rlim + resource). 3233 * 3234 * Return: Returns 0 if permission is granted. 3235 */ 3236 int security_task_setrlimit(struct task_struct *p, unsigned int resource, 3237 struct rlimit *new_rlim) 3238 { 3239 return call_int_hook(task_setrlimit, p, resource, new_rlim); 3240 } 3241 3242 /** 3243 * security_task_setscheduler() - Check if setting sched policy/param is allowed 3244 * @p: target task 3245 * 3246 * Check permission before setting scheduling policy and/or parameters of 3247 * process @p. 3248 * 3249 * Return: Returns 0 if permission is granted. 3250 */ 3251 int security_task_setscheduler(struct task_struct *p) 3252 { 3253 return call_int_hook(task_setscheduler, p); 3254 } 3255 3256 /** 3257 * security_task_getscheduler() - Check if getting scheduling info is allowed 3258 * @p: target task 3259 * 3260 * Check permission before obtaining scheduling information for process @p. 3261 * 3262 * Return: Returns 0 if permission is granted. 3263 */ 3264 int security_task_getscheduler(struct task_struct *p) 3265 { 3266 return call_int_hook(task_getscheduler, p); 3267 } 3268 3269 /** 3270 * security_task_movememory() - Check if moving memory is allowed 3271 * @p: task 3272 * 3273 * Check permission before moving memory owned by process @p. 3274 * 3275 * Return: Returns 0 if permission is granted. 3276 */ 3277 int security_task_movememory(struct task_struct *p) 3278 { 3279 return call_int_hook(task_movememory, p); 3280 } 3281 3282 /** 3283 * security_task_kill() - Check if sending a signal is allowed 3284 * @p: target process 3285 * @info: signal information 3286 * @sig: signal value 3287 * @cred: credentials of the signal sender, NULL if @current 3288 * 3289 * Check permission before sending signal @sig to @p. @info can be NULL, the 3290 * constant 1, or a pointer to a kernel_siginfo structure. If @info is 1 or 3291 * SI_FROMKERNEL(info) is true, then the signal should be viewed as coming from 3292 * the kernel and should typically be permitted. SIGIO signals are handled 3293 * separately by the send_sigiotask hook in file_security_ops. 3294 * 3295 * Return: Returns 0 if permission is granted. 3296 */ 3297 int security_task_kill(struct task_struct *p, struct kernel_siginfo *info, 3298 int sig, const struct cred *cred) 3299 { 3300 return call_int_hook(task_kill, p, info, sig, cred); 3301 } 3302 3303 /** 3304 * security_task_prctl() - Handle an LSM specific prctl() call 3305 * @option: operation 3306 * @arg2: argument 3307 * @arg3: argument 3308 * @arg4: argument 3309 * @arg5: argument 3310 * 3311 * Handle lsm specific prctl() operations. 3312 * 3313 * Return: Return -ENOSYS if no-one wanted to handle this op, any other value 3314 * to cause prctl() to return immediately with that value. 3315 */ 3316 int security_task_prctl(int option, unsigned long arg2, unsigned long arg3, 3317 unsigned long arg4, unsigned long arg5) 3318 { 3319 int thisrc; 3320 int rc = LSM_RET_DEFAULT(task_prctl); 3321 struct lsm_static_call *scall; 3322 3323 lsm_for_each_hook(scall, task_prctl) { 3324 thisrc = scall->hl->hook.task_prctl(option, arg2, arg3, arg4, arg5); 3325 if (thisrc != LSM_RET_DEFAULT(task_prctl)) { 3326 rc = thisrc; 3327 if (thisrc != 0) 3328 break; 3329 } 3330 } 3331 return rc; 3332 } 3333 3334 /** 3335 * security_task_to_inode() - Set the security attributes of a task's inode 3336 * @p: task 3337 * @inode: inode 3338 * 3339 * Set the security attributes for an inode based on an associated task's 3340 * security attributes, e.g. for /proc/pid inodes. 3341 */ 3342 void security_task_to_inode(struct task_struct *p, struct inode *inode) 3343 { 3344 call_void_hook(task_to_inode, p, inode); 3345 } 3346 3347 /** 3348 * security_create_user_ns() - Check if creating a new userns is allowed 3349 * @cred: prepared creds 3350 * 3351 * Check permission prior to creating a new user namespace. 3352 * 3353 * Return: Returns 0 if successful, otherwise < 0 error code. 3354 */ 3355 int security_create_user_ns(const struct cred *cred) 3356 { 3357 return call_int_hook(userns_create, cred); 3358 } 3359 3360 /** 3361 * security_ipc_permission() - Check if sysv ipc access is allowed 3362 * @ipcp: ipc permission structure 3363 * @flag: requested permissions 3364 * 3365 * Check permissions for access to IPC. 3366 * 3367 * Return: Returns 0 if permission is granted. 3368 */ 3369 int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 3370 { 3371 return call_int_hook(ipc_permission, ipcp, flag); 3372 } 3373 3374 /** 3375 * security_ipc_getlsmprop() - Get the sysv ipc object LSM data 3376 * @ipcp: ipc permission structure 3377 * @prop: pointer to lsm information 3378 * 3379 * Get the lsm information associated with the ipc object. 3380 */ 3381 3382 void security_ipc_getlsmprop(struct kern_ipc_perm *ipcp, struct lsm_prop *prop) 3383 { 3384 lsmprop_init(prop); 3385 call_void_hook(ipc_getlsmprop, ipcp, prop); 3386 } 3387 3388 /** 3389 * security_msg_msg_alloc() - Allocate a sysv ipc message LSM blob 3390 * @msg: message structure 3391 * 3392 * Allocate and attach a security structure to the msg->security field. The 3393 * security field is initialized to NULL when the structure is first created. 3394 * 3395 * Return: Return 0 if operation was successful and permission is granted. 3396 */ 3397 int security_msg_msg_alloc(struct msg_msg *msg) 3398 { 3399 int rc = lsm_msg_msg_alloc(msg); 3400 3401 if (unlikely(rc)) 3402 return rc; 3403 rc = call_int_hook(msg_msg_alloc_security, msg); 3404 if (unlikely(rc)) 3405 security_msg_msg_free(msg); 3406 return rc; 3407 } 3408 3409 /** 3410 * security_msg_msg_free() - Free a sysv ipc message LSM blob 3411 * @msg: message structure 3412 * 3413 * Deallocate the security structure for this message. 3414 */ 3415 void security_msg_msg_free(struct msg_msg *msg) 3416 { 3417 call_void_hook(msg_msg_free_security, msg); 3418 kfree(msg->security); 3419 msg->security = NULL; 3420 } 3421 3422 /** 3423 * security_msg_queue_alloc() - Allocate a sysv ipc msg queue LSM blob 3424 * @msq: sysv ipc permission structure 3425 * 3426 * Allocate and attach a security structure to @msg. The security field is 3427 * initialized to NULL when the structure is first created. 3428 * 3429 * Return: Returns 0 if operation was successful and permission is granted. 3430 */ 3431 int security_msg_queue_alloc(struct kern_ipc_perm *msq) 3432 { 3433 int rc = lsm_ipc_alloc(msq); 3434 3435 if (unlikely(rc)) 3436 return rc; 3437 rc = call_int_hook(msg_queue_alloc_security, msq); 3438 if (unlikely(rc)) 3439 security_msg_queue_free(msq); 3440 return rc; 3441 } 3442 3443 /** 3444 * security_msg_queue_free() - Free a sysv ipc msg queue LSM blob 3445 * @msq: sysv ipc permission structure 3446 * 3447 * Deallocate security field @perm->security for the message queue. 3448 */ 3449 void security_msg_queue_free(struct kern_ipc_perm *msq) 3450 { 3451 call_void_hook(msg_queue_free_security, msq); 3452 kfree(msq->security); 3453 msq->security = NULL; 3454 } 3455 3456 /** 3457 * security_msg_queue_associate() - Check if a msg queue operation is allowed 3458 * @msq: sysv ipc permission structure 3459 * @msqflg: operation flags 3460 * 3461 * Check permission when a message queue is requested through the msgget system 3462 * call. This hook is only called when returning the message queue identifier 3463 * for an existing message queue, not when a new message queue is created. 3464 * 3465 * Return: Return 0 if permission is granted. 3466 */ 3467 int security_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) 3468 { 3469 return call_int_hook(msg_queue_associate, msq, msqflg); 3470 } 3471 3472 /** 3473 * security_msg_queue_msgctl() - Check if a msg queue operation is allowed 3474 * @msq: sysv ipc permission structure 3475 * @cmd: operation 3476 * 3477 * Check permission when a message control operation specified by @cmd is to be 3478 * performed on the message queue with permissions. 3479 * 3480 * Return: Returns 0 if permission is granted. 3481 */ 3482 int security_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) 3483 { 3484 return call_int_hook(msg_queue_msgctl, msq, cmd); 3485 } 3486 3487 /** 3488 * security_msg_queue_msgsnd() - Check if sending a sysv ipc message is allowed 3489 * @msq: sysv ipc permission structure 3490 * @msg: message 3491 * @msqflg: operation flags 3492 * 3493 * Check permission before a message, @msg, is enqueued on the message queue 3494 * with permissions specified in @msq. 3495 * 3496 * Return: Returns 0 if permission is granted. 3497 */ 3498 int security_msg_queue_msgsnd(struct kern_ipc_perm *msq, 3499 struct msg_msg *msg, int msqflg) 3500 { 3501 return call_int_hook(msg_queue_msgsnd, msq, msg, msqflg); 3502 } 3503 3504 /** 3505 * security_msg_queue_msgrcv() - Check if receiving a sysv ipc msg is allowed 3506 * @msq: sysv ipc permission structure 3507 * @msg: message 3508 * @target: target task 3509 * @type: type of message requested 3510 * @mode: operation flags 3511 * 3512 * Check permission before a message, @msg, is removed from the message queue. 3513 * The @target task structure contains a pointer to the process that will be 3514 * receiving the message (not equal to the current process when inline receives 3515 * are being performed). 3516 * 3517 * Return: Returns 0 if permission is granted. 3518 */ 3519 int security_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, 3520 struct task_struct *target, long type, int mode) 3521 { 3522 return call_int_hook(msg_queue_msgrcv, msq, msg, target, type, mode); 3523 } 3524 3525 /** 3526 * security_shm_alloc() - Allocate a sysv shm LSM blob 3527 * @shp: sysv ipc permission structure 3528 * 3529 * Allocate and attach a security structure to the @shp security field. The 3530 * security field is initialized to NULL when the structure is first created. 3531 * 3532 * Return: Returns 0 if operation was successful and permission is granted. 3533 */ 3534 int security_shm_alloc(struct kern_ipc_perm *shp) 3535 { 3536 int rc = lsm_ipc_alloc(shp); 3537 3538 if (unlikely(rc)) 3539 return rc; 3540 rc = call_int_hook(shm_alloc_security, shp); 3541 if (unlikely(rc)) 3542 security_shm_free(shp); 3543 return rc; 3544 } 3545 3546 /** 3547 * security_shm_free() - Free a sysv shm LSM blob 3548 * @shp: sysv ipc permission structure 3549 * 3550 * Deallocate the security structure @perm->security for the memory segment. 3551 */ 3552 void security_shm_free(struct kern_ipc_perm *shp) 3553 { 3554 call_void_hook(shm_free_security, shp); 3555 kfree(shp->security); 3556 shp->security = NULL; 3557 } 3558 3559 /** 3560 * security_shm_associate() - Check if a sysv shm operation is allowed 3561 * @shp: sysv ipc permission structure 3562 * @shmflg: operation flags 3563 * 3564 * Check permission when a shared memory region is requested through the shmget 3565 * system call. This hook is only called when returning the shared memory 3566 * region identifier for an existing region, not when a new shared memory 3567 * region is created. 3568 * 3569 * Return: Returns 0 if permission is granted. 3570 */ 3571 int security_shm_associate(struct kern_ipc_perm *shp, int shmflg) 3572 { 3573 return call_int_hook(shm_associate, shp, shmflg); 3574 } 3575 3576 /** 3577 * security_shm_shmctl() - Check if a sysv shm operation is allowed 3578 * @shp: sysv ipc permission structure 3579 * @cmd: operation 3580 * 3581 * Check permission when a shared memory control operation specified by @cmd is 3582 * to be performed on the shared memory region with permissions in @shp. 3583 * 3584 * Return: Return 0 if permission is granted. 3585 */ 3586 int security_shm_shmctl(struct kern_ipc_perm *shp, int cmd) 3587 { 3588 return call_int_hook(shm_shmctl, shp, cmd); 3589 } 3590 3591 /** 3592 * security_shm_shmat() - Check if a sysv shm attach operation is allowed 3593 * @shp: sysv ipc permission structure 3594 * @shmaddr: address of memory region to attach 3595 * @shmflg: operation flags 3596 * 3597 * Check permissions prior to allowing the shmat system call to attach the 3598 * shared memory segment with permissions @shp to the data segment of the 3599 * calling process. The attaching address is specified by @shmaddr. 3600 * 3601 * Return: Returns 0 if permission is granted. 3602 */ 3603 int security_shm_shmat(struct kern_ipc_perm *shp, 3604 char __user *shmaddr, int shmflg) 3605 { 3606 return call_int_hook(shm_shmat, shp, shmaddr, shmflg); 3607 } 3608 3609 /** 3610 * security_sem_alloc() - Allocate a sysv semaphore LSM blob 3611 * @sma: sysv ipc permission structure 3612 * 3613 * Allocate and attach a security structure to the @sma security field. The 3614 * security field is initialized to NULL when the structure is first created. 3615 * 3616 * Return: Returns 0 if operation was successful and permission is granted. 3617 */ 3618 int security_sem_alloc(struct kern_ipc_perm *sma) 3619 { 3620 int rc = lsm_ipc_alloc(sma); 3621 3622 if (unlikely(rc)) 3623 return rc; 3624 rc = call_int_hook(sem_alloc_security, sma); 3625 if (unlikely(rc)) 3626 security_sem_free(sma); 3627 return rc; 3628 } 3629 3630 /** 3631 * security_sem_free() - Free a sysv semaphore LSM blob 3632 * @sma: sysv ipc permission structure 3633 * 3634 * Deallocate security structure @sma->security for the semaphore. 3635 */ 3636 void security_sem_free(struct kern_ipc_perm *sma) 3637 { 3638 call_void_hook(sem_free_security, sma); 3639 kfree(sma->security); 3640 sma->security = NULL; 3641 } 3642 3643 /** 3644 * security_sem_associate() - Check if a sysv semaphore operation is allowed 3645 * @sma: sysv ipc permission structure 3646 * @semflg: operation flags 3647 * 3648 * Check permission when a semaphore is requested through the semget system 3649 * call. This hook is only called when returning the semaphore identifier for 3650 * an existing semaphore, not when a new one must be created. 3651 * 3652 * Return: Returns 0 if permission is granted. 3653 */ 3654 int security_sem_associate(struct kern_ipc_perm *sma, int semflg) 3655 { 3656 return call_int_hook(sem_associate, sma, semflg); 3657 } 3658 3659 /** 3660 * security_sem_semctl() - Check if a sysv semaphore operation is allowed 3661 * @sma: sysv ipc permission structure 3662 * @cmd: operation 3663 * 3664 * Check permission when a semaphore operation specified by @cmd is to be 3665 * performed on the semaphore. 3666 * 3667 * Return: Returns 0 if permission is granted. 3668 */ 3669 int security_sem_semctl(struct kern_ipc_perm *sma, int cmd) 3670 { 3671 return call_int_hook(sem_semctl, sma, cmd); 3672 } 3673 3674 /** 3675 * security_sem_semop() - Check if a sysv semaphore operation is allowed 3676 * @sma: sysv ipc permission structure 3677 * @sops: operations to perform 3678 * @nsops: number of operations 3679 * @alter: flag indicating changes will be made 3680 * 3681 * Check permissions before performing operations on members of the semaphore 3682 * set. If the @alter flag is nonzero, the semaphore set may be modified. 3683 * 3684 * Return: Returns 0 if permission is granted. 3685 */ 3686 int security_sem_semop(struct kern_ipc_perm *sma, struct sembuf *sops, 3687 unsigned nsops, int alter) 3688 { 3689 return call_int_hook(sem_semop, sma, sops, nsops, alter); 3690 } 3691 3692 /** 3693 * security_d_instantiate() - Populate an inode's LSM state based on a dentry 3694 * @dentry: dentry 3695 * @inode: inode 3696 * 3697 * Fill in @inode security information for a @dentry if allowed. 3698 */ 3699 void security_d_instantiate(struct dentry *dentry, struct inode *inode) 3700 { 3701 if (unlikely(inode && IS_PRIVATE(inode))) 3702 return; 3703 call_void_hook(d_instantiate, dentry, inode); 3704 } 3705 EXPORT_SYMBOL(security_d_instantiate); 3706 3707 /* 3708 * Please keep this in sync with it's counterpart in security/lsm_syscalls.c 3709 */ 3710 3711 /** 3712 * security_getselfattr - Read an LSM attribute of the current process. 3713 * @attr: which attribute to return 3714 * @uctx: the user-space destination for the information, or NULL 3715 * @size: pointer to the size of space available to receive the data 3716 * @flags: special handling options. LSM_FLAG_SINGLE indicates that only 3717 * attributes associated with the LSM identified in the passed @ctx be 3718 * reported. 3719 * 3720 * A NULL value for @uctx can be used to get both the number of attributes 3721 * and the size of the data. 3722 * 3723 * Returns the number of attributes found on success, negative value 3724 * on error. @size is reset to the total size of the data. 3725 * If @size is insufficient to contain the data -E2BIG is returned. 3726 */ 3727 int security_getselfattr(unsigned int attr, struct lsm_ctx __user *uctx, 3728 u32 __user *size, u32 flags) 3729 { 3730 struct lsm_static_call *scall; 3731 struct lsm_ctx lctx = { .id = LSM_ID_UNDEF, }; 3732 u8 __user *base = (u8 __user *)uctx; 3733 u32 entrysize; 3734 u32 total = 0; 3735 u32 left; 3736 bool toobig = false; 3737 bool single = false; 3738 int count = 0; 3739 int rc; 3740 3741 if (attr == LSM_ATTR_UNDEF) 3742 return -EINVAL; 3743 if (size == NULL) 3744 return -EINVAL; 3745 if (get_user(left, size)) 3746 return -EFAULT; 3747 3748 if (flags) { 3749 /* 3750 * Only flag supported is LSM_FLAG_SINGLE 3751 */ 3752 if (flags != LSM_FLAG_SINGLE || !uctx) 3753 return -EINVAL; 3754 if (copy_from_user(&lctx, uctx, sizeof(lctx))) 3755 return -EFAULT; 3756 /* 3757 * If the LSM ID isn't specified it is an error. 3758 */ 3759 if (lctx.id == LSM_ID_UNDEF) 3760 return -EINVAL; 3761 single = true; 3762 } 3763 3764 /* 3765 * In the usual case gather all the data from the LSMs. 3766 * In the single case only get the data from the LSM specified. 3767 */ 3768 lsm_for_each_hook(scall, getselfattr) { 3769 if (single && lctx.id != scall->hl->lsmid->id) 3770 continue; 3771 entrysize = left; 3772 if (base) 3773 uctx = (struct lsm_ctx __user *)(base + total); 3774 rc = scall->hl->hook.getselfattr(attr, uctx, &entrysize, flags); 3775 if (rc == -EOPNOTSUPP) 3776 continue; 3777 if (rc == -E2BIG) { 3778 rc = 0; 3779 left = 0; 3780 toobig = true; 3781 } else if (rc < 0) 3782 return rc; 3783 else 3784 left -= entrysize; 3785 3786 total += entrysize; 3787 count += rc; 3788 if (single) 3789 break; 3790 } 3791 if (put_user(total, size)) 3792 return -EFAULT; 3793 if (toobig) 3794 return -E2BIG; 3795 if (count == 0) 3796 return LSM_RET_DEFAULT(getselfattr); 3797 return count; 3798 } 3799 3800 /* 3801 * Please keep this in sync with it's counterpart in security/lsm_syscalls.c 3802 */ 3803 3804 /** 3805 * security_setselfattr - Set an LSM attribute on the current process. 3806 * @attr: which attribute to set 3807 * @uctx: the user-space source for the information 3808 * @size: the size of the data 3809 * @flags: reserved for future use, must be 0 3810 * 3811 * Set an LSM attribute for the current process. The LSM, attribute 3812 * and new value are included in @uctx. 3813 * 3814 * Returns 0 on success, -EINVAL if the input is inconsistent, -EFAULT 3815 * if the user buffer is inaccessible, E2BIG if size is too big, or an 3816 * LSM specific failure. 3817 */ 3818 int security_setselfattr(unsigned int attr, struct lsm_ctx __user *uctx, 3819 u32 size, u32 flags) 3820 { 3821 struct lsm_static_call *scall; 3822 struct lsm_ctx *lctx; 3823 int rc = LSM_RET_DEFAULT(setselfattr); 3824 u64 required_len; 3825 3826 if (flags) 3827 return -EINVAL; 3828 if (size < sizeof(*lctx)) 3829 return -EINVAL; 3830 if (size > PAGE_SIZE) 3831 return -E2BIG; 3832 3833 lctx = memdup_user(uctx, size); 3834 if (IS_ERR(lctx)) 3835 return PTR_ERR(lctx); 3836 3837 if (size < lctx->len || 3838 check_add_overflow(sizeof(*lctx), lctx->ctx_len, &required_len) || 3839 lctx->len < required_len) { 3840 rc = -EINVAL; 3841 goto free_out; 3842 } 3843 3844 lsm_for_each_hook(scall, setselfattr) 3845 if ((scall->hl->lsmid->id) == lctx->id) { 3846 rc = scall->hl->hook.setselfattr(attr, lctx, size, flags); 3847 break; 3848 } 3849 3850 free_out: 3851 kfree(lctx); 3852 return rc; 3853 } 3854 3855 /** 3856 * security_getprocattr() - Read an attribute for a task 3857 * @p: the task 3858 * @lsmid: LSM identification 3859 * @name: attribute name 3860 * @value: attribute value 3861 * 3862 * Read attribute @name for task @p and store it into @value if allowed. 3863 * 3864 * Return: Returns the length of @value on success, a negative value otherwise. 3865 */ 3866 int security_getprocattr(struct task_struct *p, int lsmid, const char *name, 3867 char **value) 3868 { 3869 struct lsm_static_call *scall; 3870 3871 lsm_for_each_hook(scall, getprocattr) { 3872 if (lsmid != 0 && lsmid != scall->hl->lsmid->id) 3873 continue; 3874 return scall->hl->hook.getprocattr(p, name, value); 3875 } 3876 return LSM_RET_DEFAULT(getprocattr); 3877 } 3878 3879 /** 3880 * security_setprocattr() - Set an attribute for a task 3881 * @lsmid: LSM identification 3882 * @name: attribute name 3883 * @value: attribute value 3884 * @size: attribute value size 3885 * 3886 * Write (set) the current task's attribute @name to @value, size @size if 3887 * allowed. 3888 * 3889 * Return: Returns bytes written on success, a negative value otherwise. 3890 */ 3891 int security_setprocattr(int lsmid, const char *name, void *value, size_t size) 3892 { 3893 struct lsm_static_call *scall; 3894 3895 lsm_for_each_hook(scall, setprocattr) { 3896 if (lsmid != 0 && lsmid != scall->hl->lsmid->id) 3897 continue; 3898 return scall->hl->hook.setprocattr(name, value, size); 3899 } 3900 return LSM_RET_DEFAULT(setprocattr); 3901 } 3902 3903 /** 3904 * security_ismaclabel() - Check if the named attribute is a MAC label 3905 * @name: full extended attribute name 3906 * 3907 * Check if the extended attribute specified by @name represents a MAC label. 3908 * 3909 * Return: Returns 1 if name is a MAC attribute otherwise returns 0. 3910 */ 3911 int security_ismaclabel(const char *name) 3912 { 3913 return call_int_hook(ismaclabel, name); 3914 } 3915 EXPORT_SYMBOL(security_ismaclabel); 3916 3917 /** 3918 * security_secid_to_secctx() - Convert a secid to a secctx 3919 * @secid: secid 3920 * @cp: the LSM context 3921 * 3922 * Convert secid to security context. If @cp is NULL the length of the 3923 * result will be returned, but no data will be returned. This 3924 * does mean that the length could change between calls to check the length and 3925 * the next call which actually allocates and returns the data. 3926 * 3927 * Return: Return length of data on success, error on failure. 3928 */ 3929 int security_secid_to_secctx(u32 secid, struct lsm_context *cp) 3930 { 3931 return call_int_hook(secid_to_secctx, secid, cp); 3932 } 3933 EXPORT_SYMBOL(security_secid_to_secctx); 3934 3935 /** 3936 * security_lsmprop_to_secctx() - Convert a lsm_prop to a secctx 3937 * @prop: lsm specific information 3938 * @cp: the LSM context 3939 * @lsmid: which security module to report 3940 * 3941 * Convert a @prop entry to security context. If @cp is NULL the 3942 * length of the result will be returned. This does mean that the 3943 * length could change between calls to check the length and the 3944 * next call which actually allocates and returns the @cp. 3945 * 3946 * @lsmid identifies which LSM should supply the context. 3947 * A value of LSM_ID_UNDEF indicates that the first LSM suppling 3948 * the hook should be used. This is used in cases where the 3949 * ID of the supplying LSM is unambiguous. 3950 * 3951 * Return: Return length of data on success, error on failure. 3952 */ 3953 int security_lsmprop_to_secctx(struct lsm_prop *prop, struct lsm_context *cp, 3954 int lsmid) 3955 { 3956 struct lsm_static_call *scall; 3957 3958 lsm_for_each_hook(scall, lsmprop_to_secctx) { 3959 if (lsmid != LSM_ID_UNDEF && lsmid != scall->hl->lsmid->id) 3960 continue; 3961 return scall->hl->hook.lsmprop_to_secctx(prop, cp); 3962 } 3963 return LSM_RET_DEFAULT(lsmprop_to_secctx); 3964 } 3965 EXPORT_SYMBOL(security_lsmprop_to_secctx); 3966 3967 /** 3968 * security_secctx_to_secid() - Convert a secctx to a secid 3969 * @secdata: secctx 3970 * @seclen: length of secctx 3971 * @secid: secid 3972 * 3973 * Convert security context to secid. 3974 * 3975 * Return: Returns 0 on success, error on failure. 3976 */ 3977 int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 3978 { 3979 *secid = 0; 3980 return call_int_hook(secctx_to_secid, secdata, seclen, secid); 3981 } 3982 EXPORT_SYMBOL(security_secctx_to_secid); 3983 3984 /** 3985 * security_release_secctx() - Free a secctx buffer 3986 * @cp: the security context 3987 * 3988 * Release the security context. 3989 */ 3990 void security_release_secctx(struct lsm_context *cp) 3991 { 3992 call_void_hook(release_secctx, cp); 3993 memset(cp, 0, sizeof(*cp)); 3994 } 3995 EXPORT_SYMBOL(security_release_secctx); 3996 3997 /** 3998 * security_inode_invalidate_secctx() - Invalidate an inode's security label 3999 * @inode: inode 4000 * 4001 * Notify the security module that it must revalidate the security context of 4002 * an inode. 4003 */ 4004 void security_inode_invalidate_secctx(struct inode *inode) 4005 { 4006 call_void_hook(inode_invalidate_secctx, inode); 4007 } 4008 EXPORT_SYMBOL(security_inode_invalidate_secctx); 4009 4010 /** 4011 * security_inode_notifysecctx() - Notify the LSM of an inode's security label 4012 * @inode: inode 4013 * @ctx: secctx 4014 * @ctxlen: length of secctx 4015 * 4016 * Notify the security module of what the security context of an inode should 4017 * be. Initializes the incore security context managed by the security module 4018 * for this inode. Example usage: NFS client invokes this hook to initialize 4019 * the security context in its incore inode to the value provided by the server 4020 * for the file when the server returned the file's attributes to the client. 4021 * Must be called with inode->i_mutex locked. 4022 * 4023 * Return: Returns 0 on success, error on failure. 4024 */ 4025 int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 4026 { 4027 return call_int_hook(inode_notifysecctx, inode, ctx, ctxlen); 4028 } 4029 EXPORT_SYMBOL(security_inode_notifysecctx); 4030 4031 /** 4032 * security_inode_setsecctx() - Change the security label of an inode 4033 * @dentry: inode 4034 * @ctx: secctx 4035 * @ctxlen: length of secctx 4036 * 4037 * Change the security context of an inode. Updates the incore security 4038 * context managed by the security module and invokes the fs code as needed 4039 * (via __vfs_setxattr_noperm) to update any backing xattrs that represent the 4040 * context. Example usage: NFS server invokes this hook to change the security 4041 * context in its incore inode and on the backing filesystem to a value 4042 * provided by the client on a SETATTR operation. Must be called with 4043 * inode->i_mutex locked. 4044 * 4045 * Return: Returns 0 on success, error on failure. 4046 */ 4047 int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 4048 { 4049 return call_int_hook(inode_setsecctx, dentry, ctx, ctxlen); 4050 } 4051 EXPORT_SYMBOL(security_inode_setsecctx); 4052 4053 /** 4054 * security_inode_getsecctx() - Get the security label of an inode 4055 * @inode: inode 4056 * @cp: security context 4057 * 4058 * On success, returns 0 and fills out @cp with the security context 4059 * for the given @inode. 4060 * 4061 * Return: Returns 0 on success, error on failure. 4062 */ 4063 int security_inode_getsecctx(struct inode *inode, struct lsm_context *cp) 4064 { 4065 memset(cp, 0, sizeof(*cp)); 4066 return call_int_hook(inode_getsecctx, inode, cp); 4067 } 4068 EXPORT_SYMBOL(security_inode_getsecctx); 4069 4070 #ifdef CONFIG_WATCH_QUEUE 4071 /** 4072 * security_post_notification() - Check if a watch notification can be posted 4073 * @w_cred: credentials of the task that set the watch 4074 * @cred: credentials of the task which triggered the watch 4075 * @n: the notification 4076 * 4077 * Check to see if a watch notification can be posted to a particular queue. 4078 * 4079 * Return: Returns 0 if permission is granted. 4080 */ 4081 int security_post_notification(const struct cred *w_cred, 4082 const struct cred *cred, 4083 struct watch_notification *n) 4084 { 4085 return call_int_hook(post_notification, w_cred, cred, n); 4086 } 4087 #endif /* CONFIG_WATCH_QUEUE */ 4088 4089 #ifdef CONFIG_KEY_NOTIFICATIONS 4090 /** 4091 * security_watch_key() - Check if a task is allowed to watch for key events 4092 * @key: the key to watch 4093 * 4094 * Check to see if a process is allowed to watch for event notifications from 4095 * a key or keyring. 4096 * 4097 * Return: Returns 0 if permission is granted. 4098 */ 4099 int security_watch_key(struct key *key) 4100 { 4101 return call_int_hook(watch_key, key); 4102 } 4103 #endif /* CONFIG_KEY_NOTIFICATIONS */ 4104 4105 #ifdef CONFIG_SECURITY_NETWORK 4106 /** 4107 * security_netlink_send() - Save info and check if netlink sending is allowed 4108 * @sk: sending socket 4109 * @skb: netlink message 4110 * 4111 * Save security information for a netlink message so that permission checking 4112 * can be performed when the message is processed. The security information 4113 * can be saved using the eff_cap field of the netlink_skb_parms structure. 4114 * Also may be used to provide fine grained control over message transmission. 4115 * 4116 * Return: Returns 0 if the information was successfully saved and message is 4117 * allowed to be transmitted. 4118 */ 4119 int security_netlink_send(struct sock *sk, struct sk_buff *skb) 4120 { 4121 return call_int_hook(netlink_send, sk, skb); 4122 } 4123 4124 /** 4125 * security_unix_stream_connect() - Check if a AF_UNIX stream is allowed 4126 * @sock: originating sock 4127 * @other: peer sock 4128 * @newsk: new sock 4129 * 4130 * Check permissions before establishing a Unix domain stream connection 4131 * between @sock and @other. 4132 * 4133 * The @unix_stream_connect and @unix_may_send hooks were necessary because 4134 * Linux provides an alternative to the conventional file name space for Unix 4135 * domain sockets. Whereas binding and connecting to sockets in the file name 4136 * space is mediated by the typical file permissions (and caught by the mknod 4137 * and permission hooks in inode_security_ops), binding and connecting to 4138 * sockets in the abstract name space is completely unmediated. Sufficient 4139 * control of Unix domain sockets in the abstract name space isn't possible 4140 * using only the socket layer hooks, since we need to know the actual target 4141 * socket, which is not looked up until we are inside the af_unix code. 4142 * 4143 * Return: Returns 0 if permission is granted. 4144 */ 4145 int security_unix_stream_connect(struct sock *sock, struct sock *other, 4146 struct sock *newsk) 4147 { 4148 return call_int_hook(unix_stream_connect, sock, other, newsk); 4149 } 4150 EXPORT_SYMBOL(security_unix_stream_connect); 4151 4152 /** 4153 * security_unix_may_send() - Check if AF_UNIX socket can send datagrams 4154 * @sock: originating sock 4155 * @other: peer sock 4156 * 4157 * Check permissions before connecting or sending datagrams from @sock to 4158 * @other. 4159 * 4160 * The @unix_stream_connect and @unix_may_send hooks were necessary because 4161 * Linux provides an alternative to the conventional file name space for Unix 4162 * domain sockets. Whereas binding and connecting to sockets in the file name 4163 * space is mediated by the typical file permissions (and caught by the mknod 4164 * and permission hooks in inode_security_ops), binding and connecting to 4165 * sockets in the abstract name space is completely unmediated. Sufficient 4166 * control of Unix domain sockets in the abstract name space isn't possible 4167 * using only the socket layer hooks, since we need to know the actual target 4168 * socket, which is not looked up until we are inside the af_unix code. 4169 * 4170 * Return: Returns 0 if permission is granted. 4171 */ 4172 int security_unix_may_send(struct socket *sock, struct socket *other) 4173 { 4174 return call_int_hook(unix_may_send, sock, other); 4175 } 4176 EXPORT_SYMBOL(security_unix_may_send); 4177 4178 /** 4179 * security_socket_create() - Check if creating a new socket is allowed 4180 * @family: protocol family 4181 * @type: communications type 4182 * @protocol: requested protocol 4183 * @kern: set to 1 if a kernel socket is requested 4184 * 4185 * Check permissions prior to creating a new socket. 4186 * 4187 * Return: Returns 0 if permission is granted. 4188 */ 4189 int security_socket_create(int family, int type, int protocol, int kern) 4190 { 4191 return call_int_hook(socket_create, family, type, protocol, kern); 4192 } 4193 4194 /** 4195 * security_socket_post_create() - Initialize a newly created socket 4196 * @sock: socket 4197 * @family: protocol family 4198 * @type: communications type 4199 * @protocol: requested protocol 4200 * @kern: set to 1 if a kernel socket is requested 4201 * 4202 * This hook allows a module to update or allocate a per-socket security 4203 * structure. Note that the security field was not added directly to the socket 4204 * structure, but rather, the socket security information is stored in the 4205 * associated inode. Typically, the inode alloc_security hook will allocate 4206 * and attach security information to SOCK_INODE(sock)->i_security. This hook 4207 * may be used to update the SOCK_INODE(sock)->i_security field with additional 4208 * information that wasn't available when the inode was allocated. 4209 * 4210 * Return: Returns 0 if permission is granted. 4211 */ 4212 int security_socket_post_create(struct socket *sock, int family, 4213 int type, int protocol, int kern) 4214 { 4215 return call_int_hook(socket_post_create, sock, family, type, 4216 protocol, kern); 4217 } 4218 4219 /** 4220 * security_socket_socketpair() - Check if creating a socketpair is allowed 4221 * @socka: first socket 4222 * @sockb: second socket 4223 * 4224 * Check permissions before creating a fresh pair of sockets. 4225 * 4226 * Return: Returns 0 if permission is granted and the connection was 4227 * established. 4228 */ 4229 int security_socket_socketpair(struct socket *socka, struct socket *sockb) 4230 { 4231 return call_int_hook(socket_socketpair, socka, sockb); 4232 } 4233 EXPORT_SYMBOL(security_socket_socketpair); 4234 4235 /** 4236 * security_socket_bind() - Check if a socket bind operation is allowed 4237 * @sock: socket 4238 * @address: requested bind address 4239 * @addrlen: length of address 4240 * 4241 * Check permission before socket protocol layer bind operation is performed 4242 * and the socket @sock is bound to the address specified in the @address 4243 * parameter. 4244 * 4245 * Return: Returns 0 if permission is granted. 4246 */ 4247 int security_socket_bind(struct socket *sock, 4248 struct sockaddr *address, int addrlen) 4249 { 4250 return call_int_hook(socket_bind, sock, address, addrlen); 4251 } 4252 4253 /** 4254 * security_socket_connect() - Check if a socket connect operation is allowed 4255 * @sock: socket 4256 * @address: address of remote connection point 4257 * @addrlen: length of address 4258 * 4259 * Check permission before socket protocol layer connect operation attempts to 4260 * connect socket @sock to a remote address, @address. 4261 * 4262 * Return: Returns 0 if permission is granted. 4263 */ 4264 int security_socket_connect(struct socket *sock, 4265 struct sockaddr *address, int addrlen) 4266 { 4267 return call_int_hook(socket_connect, sock, address, addrlen); 4268 } 4269 4270 /** 4271 * security_socket_listen() - Check if a socket is allowed to listen 4272 * @sock: socket 4273 * @backlog: connection queue size 4274 * 4275 * Check permission before socket protocol layer listen operation. 4276 * 4277 * Return: Returns 0 if permission is granted. 4278 */ 4279 int security_socket_listen(struct socket *sock, int backlog) 4280 { 4281 return call_int_hook(socket_listen, sock, backlog); 4282 } 4283 4284 /** 4285 * security_socket_accept() - Check if a socket is allowed to accept connections 4286 * @sock: listening socket 4287 * @newsock: newly creation connection socket 4288 * 4289 * Check permission before accepting a new connection. Note that the new 4290 * socket, @newsock, has been created and some information copied to it, but 4291 * the accept operation has not actually been performed. 4292 * 4293 * Return: Returns 0 if permission is granted. 4294 */ 4295 int security_socket_accept(struct socket *sock, struct socket *newsock) 4296 { 4297 return call_int_hook(socket_accept, sock, newsock); 4298 } 4299 4300 /** 4301 * security_socket_sendmsg() - Check if sending a message is allowed 4302 * @sock: sending socket 4303 * @msg: message to send 4304 * @size: size of message 4305 * 4306 * Check permission before transmitting a message to another socket. 4307 * 4308 * Return: Returns 0 if permission is granted. 4309 */ 4310 int security_socket_sendmsg(struct socket *sock, struct msghdr *msg, int size) 4311 { 4312 return call_int_hook(socket_sendmsg, sock, msg, size); 4313 } 4314 4315 /** 4316 * security_socket_recvmsg() - Check if receiving a message is allowed 4317 * @sock: receiving socket 4318 * @msg: message to receive 4319 * @size: size of message 4320 * @flags: operational flags 4321 * 4322 * Check permission before receiving a message from a socket. 4323 * 4324 * Return: Returns 0 if permission is granted. 4325 */ 4326 int security_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4327 int size, int flags) 4328 { 4329 return call_int_hook(socket_recvmsg, sock, msg, size, flags); 4330 } 4331 4332 /** 4333 * security_socket_getsockname() - Check if reading the socket addr is allowed 4334 * @sock: socket 4335 * 4336 * Check permission before reading the local address (name) of the socket 4337 * object. 4338 * 4339 * Return: Returns 0 if permission is granted. 4340 */ 4341 int security_socket_getsockname(struct socket *sock) 4342 { 4343 return call_int_hook(socket_getsockname, sock); 4344 } 4345 4346 /** 4347 * security_socket_getpeername() - Check if reading the peer's addr is allowed 4348 * @sock: socket 4349 * 4350 * Check permission before the remote address (name) of a socket object. 4351 * 4352 * Return: Returns 0 if permission is granted. 4353 */ 4354 int security_socket_getpeername(struct socket *sock) 4355 { 4356 return call_int_hook(socket_getpeername, sock); 4357 } 4358 4359 /** 4360 * security_socket_getsockopt() - Check if reading a socket option is allowed 4361 * @sock: socket 4362 * @level: option's protocol level 4363 * @optname: option name 4364 * 4365 * Check permissions before retrieving the options associated with socket 4366 * @sock. 4367 * 4368 * Return: Returns 0 if permission is granted. 4369 */ 4370 int security_socket_getsockopt(struct socket *sock, int level, int optname) 4371 { 4372 return call_int_hook(socket_getsockopt, sock, level, optname); 4373 } 4374 4375 /** 4376 * security_socket_setsockopt() - Check if setting a socket option is allowed 4377 * @sock: socket 4378 * @level: option's protocol level 4379 * @optname: option name 4380 * 4381 * Check permissions before setting the options associated with socket @sock. 4382 * 4383 * Return: Returns 0 if permission is granted. 4384 */ 4385 int security_socket_setsockopt(struct socket *sock, int level, int optname) 4386 { 4387 return call_int_hook(socket_setsockopt, sock, level, optname); 4388 } 4389 4390 /** 4391 * security_socket_shutdown() - Checks if shutting down the socket is allowed 4392 * @sock: socket 4393 * @how: flag indicating how sends and receives are handled 4394 * 4395 * Checks permission before all or part of a connection on the socket @sock is 4396 * shut down. 4397 * 4398 * Return: Returns 0 if permission is granted. 4399 */ 4400 int security_socket_shutdown(struct socket *sock, int how) 4401 { 4402 return call_int_hook(socket_shutdown, sock, how); 4403 } 4404 4405 /** 4406 * security_sock_rcv_skb() - Check if an incoming network packet is allowed 4407 * @sk: destination sock 4408 * @skb: incoming packet 4409 * 4410 * Check permissions on incoming network packets. This hook is distinct from 4411 * Netfilter's IP input hooks since it is the first time that the incoming 4412 * sk_buff @skb has been associated with a particular socket, @sk. Must not 4413 * sleep inside this hook because some callers hold spinlocks. 4414 * 4415 * Return: Returns 0 if permission is granted. 4416 */ 4417 int security_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 4418 { 4419 return call_int_hook(socket_sock_rcv_skb, sk, skb); 4420 } 4421 EXPORT_SYMBOL(security_sock_rcv_skb); 4422 4423 /** 4424 * security_socket_getpeersec_stream() - Get the remote peer label 4425 * @sock: socket 4426 * @optval: destination buffer 4427 * @optlen: size of peer label copied into the buffer 4428 * @len: maximum size of the destination buffer 4429 * 4430 * This hook allows the security module to provide peer socket security state 4431 * for unix or connected tcp sockets to userspace via getsockopt SO_GETPEERSEC. 4432 * For tcp sockets this can be meaningful if the socket is associated with an 4433 * ipsec SA. 4434 * 4435 * Return: Returns 0 if all is well, otherwise, typical getsockopt return 4436 * values. 4437 */ 4438 int security_socket_getpeersec_stream(struct socket *sock, sockptr_t optval, 4439 sockptr_t optlen, unsigned int len) 4440 { 4441 return call_int_hook(socket_getpeersec_stream, sock, optval, optlen, 4442 len); 4443 } 4444 4445 /** 4446 * security_socket_getpeersec_dgram() - Get the remote peer label 4447 * @sock: socket 4448 * @skb: datagram packet 4449 * @secid: remote peer label secid 4450 * 4451 * This hook allows the security module to provide peer socket security state 4452 * for udp sockets on a per-packet basis to userspace via getsockopt 4453 * SO_GETPEERSEC. The application must first have indicated the IP_PASSSEC 4454 * option via getsockopt. It can then retrieve the security state returned by 4455 * this hook for a packet via the SCM_SECURITY ancillary message type. 4456 * 4457 * Return: Returns 0 on success, error on failure. 4458 */ 4459 int security_socket_getpeersec_dgram(struct socket *sock, 4460 struct sk_buff *skb, u32 *secid) 4461 { 4462 return call_int_hook(socket_getpeersec_dgram, sock, skb, secid); 4463 } 4464 EXPORT_SYMBOL(security_socket_getpeersec_dgram); 4465 4466 /** 4467 * lsm_sock_alloc - allocate a composite sock blob 4468 * @sock: the sock that needs a blob 4469 * @gfp: allocation mode 4470 * 4471 * Allocate the sock blob for all the modules 4472 * 4473 * Returns 0, or -ENOMEM if memory can't be allocated. 4474 */ 4475 static int lsm_sock_alloc(struct sock *sock, gfp_t gfp) 4476 { 4477 return lsm_blob_alloc(&sock->sk_security, blob_sizes.lbs_sock, gfp); 4478 } 4479 4480 /** 4481 * security_sk_alloc() - Allocate and initialize a sock's LSM blob 4482 * @sk: sock 4483 * @family: protocol family 4484 * @priority: gfp flags 4485 * 4486 * Allocate and attach a security structure to the sk->sk_security field, which 4487 * is used to copy security attributes between local stream sockets. 4488 * 4489 * Return: Returns 0 on success, error on failure. 4490 */ 4491 int security_sk_alloc(struct sock *sk, int family, gfp_t priority) 4492 { 4493 int rc = lsm_sock_alloc(sk, priority); 4494 4495 if (unlikely(rc)) 4496 return rc; 4497 rc = call_int_hook(sk_alloc_security, sk, family, priority); 4498 if (unlikely(rc)) 4499 security_sk_free(sk); 4500 return rc; 4501 } 4502 4503 /** 4504 * security_sk_free() - Free the sock's LSM blob 4505 * @sk: sock 4506 * 4507 * Deallocate security structure. 4508 */ 4509 void security_sk_free(struct sock *sk) 4510 { 4511 call_void_hook(sk_free_security, sk); 4512 kfree(sk->sk_security); 4513 sk->sk_security = NULL; 4514 } 4515 4516 /** 4517 * security_sk_clone() - Clone a sock's LSM state 4518 * @sk: original sock 4519 * @newsk: target sock 4520 * 4521 * Clone/copy security structure. 4522 */ 4523 void security_sk_clone(const struct sock *sk, struct sock *newsk) 4524 { 4525 call_void_hook(sk_clone_security, sk, newsk); 4526 } 4527 EXPORT_SYMBOL(security_sk_clone); 4528 4529 /** 4530 * security_sk_classify_flow() - Set a flow's secid based on socket 4531 * @sk: original socket 4532 * @flic: target flow 4533 * 4534 * Set the target flow's secid to socket's secid. 4535 */ 4536 void security_sk_classify_flow(const struct sock *sk, struct flowi_common *flic) 4537 { 4538 call_void_hook(sk_getsecid, sk, &flic->flowic_secid); 4539 } 4540 EXPORT_SYMBOL(security_sk_classify_flow); 4541 4542 /** 4543 * security_req_classify_flow() - Set a flow's secid based on request_sock 4544 * @req: request_sock 4545 * @flic: target flow 4546 * 4547 * Sets @flic's secid to @req's secid. 4548 */ 4549 void security_req_classify_flow(const struct request_sock *req, 4550 struct flowi_common *flic) 4551 { 4552 call_void_hook(req_classify_flow, req, flic); 4553 } 4554 EXPORT_SYMBOL(security_req_classify_flow); 4555 4556 /** 4557 * security_sock_graft() - Reconcile LSM state when grafting a sock on a socket 4558 * @sk: sock being grafted 4559 * @parent: target parent socket 4560 * 4561 * Sets @parent's inode secid to @sk's secid and update @sk with any necessary 4562 * LSM state from @parent. 4563 */ 4564 void security_sock_graft(struct sock *sk, struct socket *parent) 4565 { 4566 call_void_hook(sock_graft, sk, parent); 4567 } 4568 EXPORT_SYMBOL(security_sock_graft); 4569 4570 /** 4571 * security_inet_conn_request() - Set request_sock state using incoming connect 4572 * @sk: parent listening sock 4573 * @skb: incoming connection 4574 * @req: new request_sock 4575 * 4576 * Initialize the @req LSM state based on @sk and the incoming connect in @skb. 4577 * 4578 * Return: Returns 0 if permission is granted. 4579 */ 4580 int security_inet_conn_request(const struct sock *sk, 4581 struct sk_buff *skb, struct request_sock *req) 4582 { 4583 return call_int_hook(inet_conn_request, sk, skb, req); 4584 } 4585 EXPORT_SYMBOL(security_inet_conn_request); 4586 4587 /** 4588 * security_inet_csk_clone() - Set new sock LSM state based on request_sock 4589 * @newsk: new sock 4590 * @req: connection request_sock 4591 * 4592 * Set that LSM state of @sock using the LSM state from @req. 4593 */ 4594 void security_inet_csk_clone(struct sock *newsk, 4595 const struct request_sock *req) 4596 { 4597 call_void_hook(inet_csk_clone, newsk, req); 4598 } 4599 4600 /** 4601 * security_inet_conn_established() - Update sock's LSM state with connection 4602 * @sk: sock 4603 * @skb: connection packet 4604 * 4605 * Update @sock's LSM state to represent a new connection from @skb. 4606 */ 4607 void security_inet_conn_established(struct sock *sk, 4608 struct sk_buff *skb) 4609 { 4610 call_void_hook(inet_conn_established, sk, skb); 4611 } 4612 EXPORT_SYMBOL(security_inet_conn_established); 4613 4614 /** 4615 * security_secmark_relabel_packet() - Check if setting a secmark is allowed 4616 * @secid: new secmark value 4617 * 4618 * Check if the process should be allowed to relabel packets to @secid. 4619 * 4620 * Return: Returns 0 if permission is granted. 4621 */ 4622 int security_secmark_relabel_packet(u32 secid) 4623 { 4624 return call_int_hook(secmark_relabel_packet, secid); 4625 } 4626 EXPORT_SYMBOL(security_secmark_relabel_packet); 4627 4628 /** 4629 * security_secmark_refcount_inc() - Increment the secmark labeling rule count 4630 * 4631 * Tells the LSM to increment the number of secmark labeling rules loaded. 4632 */ 4633 void security_secmark_refcount_inc(void) 4634 { 4635 call_void_hook(secmark_refcount_inc); 4636 } 4637 EXPORT_SYMBOL(security_secmark_refcount_inc); 4638 4639 /** 4640 * security_secmark_refcount_dec() - Decrement the secmark labeling rule count 4641 * 4642 * Tells the LSM to decrement the number of secmark labeling rules loaded. 4643 */ 4644 void security_secmark_refcount_dec(void) 4645 { 4646 call_void_hook(secmark_refcount_dec); 4647 } 4648 EXPORT_SYMBOL(security_secmark_refcount_dec); 4649 4650 /** 4651 * security_tun_dev_alloc_security() - Allocate a LSM blob for a TUN device 4652 * @security: pointer to the LSM blob 4653 * 4654 * This hook allows a module to allocate a security structure for a TUN device, 4655 * returning the pointer in @security. 4656 * 4657 * Return: Returns a zero on success, negative values on failure. 4658 */ 4659 int security_tun_dev_alloc_security(void **security) 4660 { 4661 int rc; 4662 4663 rc = lsm_blob_alloc(security, blob_sizes.lbs_tun_dev, GFP_KERNEL); 4664 if (rc) 4665 return rc; 4666 4667 rc = call_int_hook(tun_dev_alloc_security, *security); 4668 if (rc) { 4669 kfree(*security); 4670 *security = NULL; 4671 } 4672 return rc; 4673 } 4674 EXPORT_SYMBOL(security_tun_dev_alloc_security); 4675 4676 /** 4677 * security_tun_dev_free_security() - Free a TUN device LSM blob 4678 * @security: LSM blob 4679 * 4680 * This hook allows a module to free the security structure for a TUN device. 4681 */ 4682 void security_tun_dev_free_security(void *security) 4683 { 4684 kfree(security); 4685 } 4686 EXPORT_SYMBOL(security_tun_dev_free_security); 4687 4688 /** 4689 * security_tun_dev_create() - Check if creating a TUN device is allowed 4690 * 4691 * Check permissions prior to creating a new TUN device. 4692 * 4693 * Return: Returns 0 if permission is granted. 4694 */ 4695 int security_tun_dev_create(void) 4696 { 4697 return call_int_hook(tun_dev_create); 4698 } 4699 EXPORT_SYMBOL(security_tun_dev_create); 4700 4701 /** 4702 * security_tun_dev_attach_queue() - Check if attaching a TUN queue is allowed 4703 * @security: TUN device LSM blob 4704 * 4705 * Check permissions prior to attaching to a TUN device queue. 4706 * 4707 * Return: Returns 0 if permission is granted. 4708 */ 4709 int security_tun_dev_attach_queue(void *security) 4710 { 4711 return call_int_hook(tun_dev_attach_queue, security); 4712 } 4713 EXPORT_SYMBOL(security_tun_dev_attach_queue); 4714 4715 /** 4716 * security_tun_dev_attach() - Update TUN device LSM state on attach 4717 * @sk: associated sock 4718 * @security: TUN device LSM blob 4719 * 4720 * This hook can be used by the module to update any security state associated 4721 * with the TUN device's sock structure. 4722 * 4723 * Return: Returns 0 if permission is granted. 4724 */ 4725 int security_tun_dev_attach(struct sock *sk, void *security) 4726 { 4727 return call_int_hook(tun_dev_attach, sk, security); 4728 } 4729 EXPORT_SYMBOL(security_tun_dev_attach); 4730 4731 /** 4732 * security_tun_dev_open() - Update TUN device LSM state on open 4733 * @security: TUN device LSM blob 4734 * 4735 * This hook can be used by the module to update any security state associated 4736 * with the TUN device's security structure. 4737 * 4738 * Return: Returns 0 if permission is granted. 4739 */ 4740 int security_tun_dev_open(void *security) 4741 { 4742 return call_int_hook(tun_dev_open, security); 4743 } 4744 EXPORT_SYMBOL(security_tun_dev_open); 4745 4746 /** 4747 * security_sctp_assoc_request() - Update the LSM on a SCTP association req 4748 * @asoc: SCTP association 4749 * @skb: packet requesting the association 4750 * 4751 * Passes the @asoc and @chunk->skb of the association INIT packet to the LSM. 4752 * 4753 * Return: Returns 0 on success, error on failure. 4754 */ 4755 int security_sctp_assoc_request(struct sctp_association *asoc, 4756 struct sk_buff *skb) 4757 { 4758 return call_int_hook(sctp_assoc_request, asoc, skb); 4759 } 4760 EXPORT_SYMBOL(security_sctp_assoc_request); 4761 4762 /** 4763 * security_sctp_bind_connect() - Validate a list of addrs for a SCTP option 4764 * @sk: socket 4765 * @optname: SCTP option to validate 4766 * @address: list of IP addresses to validate 4767 * @addrlen: length of the address list 4768 * 4769 * Validiate permissions required for each address associated with sock @sk. 4770 * Depending on @optname, the addresses will be treated as either a connect or 4771 * bind service. The @addrlen is calculated on each IPv4 and IPv6 address using 4772 * sizeof(struct sockaddr_in) or sizeof(struct sockaddr_in6). 4773 * 4774 * Return: Returns 0 on success, error on failure. 4775 */ 4776 int security_sctp_bind_connect(struct sock *sk, int optname, 4777 struct sockaddr *address, int addrlen) 4778 { 4779 return call_int_hook(sctp_bind_connect, sk, optname, address, addrlen); 4780 } 4781 EXPORT_SYMBOL(security_sctp_bind_connect); 4782 4783 /** 4784 * security_sctp_sk_clone() - Clone a SCTP sock's LSM state 4785 * @asoc: SCTP association 4786 * @sk: original sock 4787 * @newsk: target sock 4788 * 4789 * Called whenever a new socket is created by accept(2) (i.e. a TCP style 4790 * socket) or when a socket is 'peeled off' e.g userspace calls 4791 * sctp_peeloff(3). 4792 */ 4793 void security_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk, 4794 struct sock *newsk) 4795 { 4796 call_void_hook(sctp_sk_clone, asoc, sk, newsk); 4797 } 4798 EXPORT_SYMBOL(security_sctp_sk_clone); 4799 4800 /** 4801 * security_sctp_assoc_established() - Update LSM state when assoc established 4802 * @asoc: SCTP association 4803 * @skb: packet establishing the association 4804 * 4805 * Passes the @asoc and @chunk->skb of the association COOKIE_ACK packet to the 4806 * security module. 4807 * 4808 * Return: Returns 0 if permission is granted. 4809 */ 4810 int security_sctp_assoc_established(struct sctp_association *asoc, 4811 struct sk_buff *skb) 4812 { 4813 return call_int_hook(sctp_assoc_established, asoc, skb); 4814 } 4815 EXPORT_SYMBOL(security_sctp_assoc_established); 4816 4817 /** 4818 * security_mptcp_add_subflow() - Inherit the LSM label from the MPTCP socket 4819 * @sk: the owning MPTCP socket 4820 * @ssk: the new subflow 4821 * 4822 * Update the labeling for the given MPTCP subflow, to match the one of the 4823 * owning MPTCP socket. This hook has to be called after the socket creation and 4824 * initialization via the security_socket_create() and 4825 * security_socket_post_create() LSM hooks. 4826 * 4827 * Return: Returns 0 on success or a negative error code on failure. 4828 */ 4829 int security_mptcp_add_subflow(struct sock *sk, struct sock *ssk) 4830 { 4831 return call_int_hook(mptcp_add_subflow, sk, ssk); 4832 } 4833 4834 #endif /* CONFIG_SECURITY_NETWORK */ 4835 4836 #if defined(CONFIG_SECURITY_NETWORK) && defined(CONFIG_SECURITY_PATH) 4837 /** 4838 * security_unix_find() - Check if a named AF_UNIX socket can connect 4839 * @path: path of the socket being connected to 4840 * @other: peer sock 4841 * @flags: flags associated with the socket 4842 * 4843 * This hook is called to check permissions before connecting to a named 4844 * AF_UNIX socket. The caller does not hold any locks on @other. 4845 * 4846 * Return: Returns 0 if permission is granted. 4847 */ 4848 int security_unix_find(const struct path *path, struct sock *other, int flags) 4849 { 4850 return call_int_hook(unix_find, path, other, flags); 4851 } 4852 EXPORT_SYMBOL(security_unix_find); 4853 4854 #endif /* CONFIG_SECURITY_NETWORK && CONFIG_SECURITY_PATH */ 4855 4856 #ifdef CONFIG_SECURITY_INFINIBAND 4857 /** 4858 * security_ib_pkey_access() - Check if access to an IB pkey is allowed 4859 * @sec: LSM blob 4860 * @subnet_prefix: subnet prefix of the port 4861 * @pkey: IB pkey 4862 * 4863 * Check permission to access a pkey when modifying a QP. 4864 * 4865 * Return: Returns 0 if permission is granted. 4866 */ 4867 int security_ib_pkey_access(void *sec, u64 subnet_prefix, u16 pkey) 4868 { 4869 return call_int_hook(ib_pkey_access, sec, subnet_prefix, pkey); 4870 } 4871 EXPORT_SYMBOL(security_ib_pkey_access); 4872 4873 /** 4874 * security_ib_endport_manage_subnet() - Check if SMPs traffic is allowed 4875 * @sec: LSM blob 4876 * @dev_name: IB device name 4877 * @port_num: port number 4878 * 4879 * Check permissions to send and receive SMPs on a end port. 4880 * 4881 * Return: Returns 0 if permission is granted. 4882 */ 4883 int security_ib_endport_manage_subnet(void *sec, 4884 const char *dev_name, u8 port_num) 4885 { 4886 return call_int_hook(ib_endport_manage_subnet, sec, dev_name, port_num); 4887 } 4888 EXPORT_SYMBOL(security_ib_endport_manage_subnet); 4889 4890 /** 4891 * security_ib_alloc_security() - Allocate an Infiniband LSM blob 4892 * @sec: LSM blob 4893 * 4894 * Allocate a security structure for Infiniband objects. 4895 * 4896 * Return: Returns 0 on success, non-zero on failure. 4897 */ 4898 int security_ib_alloc_security(void **sec) 4899 { 4900 int rc; 4901 4902 rc = lsm_blob_alloc(sec, blob_sizes.lbs_ib, GFP_KERNEL); 4903 if (rc) 4904 return rc; 4905 4906 rc = call_int_hook(ib_alloc_security, *sec); 4907 if (rc) { 4908 kfree(*sec); 4909 *sec = NULL; 4910 } 4911 return rc; 4912 } 4913 EXPORT_SYMBOL(security_ib_alloc_security); 4914 4915 /** 4916 * security_ib_free_security() - Free an Infiniband LSM blob 4917 * @sec: LSM blob 4918 * 4919 * Deallocate an Infiniband security structure. 4920 */ 4921 void security_ib_free_security(void *sec) 4922 { 4923 kfree(sec); 4924 } 4925 EXPORT_SYMBOL(security_ib_free_security); 4926 #endif /* CONFIG_SECURITY_INFINIBAND */ 4927 4928 #ifdef CONFIG_SECURITY_NETWORK_XFRM 4929 /** 4930 * security_xfrm_policy_alloc() - Allocate a xfrm policy LSM blob 4931 * @ctxp: xfrm security context being added to the SPD 4932 * @sec_ctx: security label provided by userspace 4933 * @gfp: gfp flags 4934 * 4935 * Allocate a security structure to the xp->security field; the security field 4936 * is initialized to NULL when the xfrm_policy is allocated. 4937 * 4938 * Return: Return 0 if operation was successful. 4939 */ 4940 int security_xfrm_policy_alloc(struct xfrm_sec_ctx **ctxp, 4941 struct xfrm_user_sec_ctx *sec_ctx, 4942 gfp_t gfp) 4943 { 4944 return call_int_hook(xfrm_policy_alloc_security, ctxp, sec_ctx, gfp); 4945 } 4946 EXPORT_SYMBOL(security_xfrm_policy_alloc); 4947 4948 /** 4949 * security_xfrm_policy_clone() - Clone xfrm policy LSM state 4950 * @old_ctx: xfrm security context 4951 * @new_ctxp: target xfrm security context 4952 * 4953 * Allocate a security structure in new_ctxp that contains the information from 4954 * the old_ctx structure. 4955 * 4956 * Return: Return 0 if operation was successful. 4957 */ 4958 int security_xfrm_policy_clone(struct xfrm_sec_ctx *old_ctx, 4959 struct xfrm_sec_ctx **new_ctxp) 4960 { 4961 return call_int_hook(xfrm_policy_clone_security, old_ctx, new_ctxp); 4962 } 4963 4964 /** 4965 * security_xfrm_policy_free() - Free a xfrm security context 4966 * @ctx: xfrm security context 4967 * 4968 * Free LSM resources associated with @ctx. 4969 */ 4970 void security_xfrm_policy_free(struct xfrm_sec_ctx *ctx) 4971 { 4972 call_void_hook(xfrm_policy_free_security, ctx); 4973 } 4974 EXPORT_SYMBOL(security_xfrm_policy_free); 4975 4976 /** 4977 * security_xfrm_policy_delete() - Check if deleting a xfrm policy is allowed 4978 * @ctx: xfrm security context 4979 * 4980 * Authorize deletion of a SPD entry. 4981 * 4982 * Return: Returns 0 if permission is granted. 4983 */ 4984 int security_xfrm_policy_delete(struct xfrm_sec_ctx *ctx) 4985 { 4986 return call_int_hook(xfrm_policy_delete_security, ctx); 4987 } 4988 4989 /** 4990 * security_xfrm_state_alloc() - Allocate a xfrm state LSM blob 4991 * @x: xfrm state being added to the SAD 4992 * @sec_ctx: security label provided by userspace 4993 * 4994 * Allocate a security structure to the @x->security field; the security field 4995 * is initialized to NULL when the xfrm_state is allocated. Set the context to 4996 * correspond to @sec_ctx. 4997 * 4998 * Return: Return 0 if operation was successful. 4999 */ 5000 int security_xfrm_state_alloc(struct xfrm_state *x, 5001 struct xfrm_user_sec_ctx *sec_ctx) 5002 { 5003 return call_int_hook(xfrm_state_alloc, x, sec_ctx); 5004 } 5005 EXPORT_SYMBOL(security_xfrm_state_alloc); 5006 5007 /** 5008 * security_xfrm_state_alloc_acquire() - Allocate a xfrm state LSM blob 5009 * @x: xfrm state being added to the SAD 5010 * @polsec: associated policy's security context 5011 * @secid: secid from the flow 5012 * 5013 * Allocate a security structure to the x->security field; the security field 5014 * is initialized to NULL when the xfrm_state is allocated. Set the context to 5015 * correspond to secid. 5016 * 5017 * Return: Returns 0 if operation was successful. 5018 */ 5019 int security_xfrm_state_alloc_acquire(struct xfrm_state *x, 5020 struct xfrm_sec_ctx *polsec, u32 secid) 5021 { 5022 return call_int_hook(xfrm_state_alloc_acquire, x, polsec, secid); 5023 } 5024 5025 /** 5026 * security_xfrm_state_delete() - Check if deleting a xfrm state is allowed 5027 * @x: xfrm state 5028 * 5029 * Authorize deletion of x->security. 5030 * 5031 * Return: Returns 0 if permission is granted. 5032 */ 5033 int security_xfrm_state_delete(struct xfrm_state *x) 5034 { 5035 return call_int_hook(xfrm_state_delete_security, x); 5036 } 5037 EXPORT_SYMBOL(security_xfrm_state_delete); 5038 5039 /** 5040 * security_xfrm_state_free() - Free a xfrm state 5041 * @x: xfrm state 5042 * 5043 * Deallocate x->security. 5044 */ 5045 void security_xfrm_state_free(struct xfrm_state *x) 5046 { 5047 call_void_hook(xfrm_state_free_security, x); 5048 } 5049 5050 /** 5051 * security_xfrm_policy_lookup() - Check if using a xfrm policy is allowed 5052 * @ctx: target xfrm security context 5053 * @fl_secid: flow secid used to authorize access 5054 * 5055 * Check permission when a flow selects a xfrm_policy for processing XFRMs on a 5056 * packet. The hook is called when selecting either a per-socket policy or a 5057 * generic xfrm policy. 5058 * 5059 * Return: Return 0 if permission is granted, -ESRCH otherwise, or -errno on 5060 * other errors. 5061 */ 5062 int security_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_secid) 5063 { 5064 return call_int_hook(xfrm_policy_lookup, ctx, fl_secid); 5065 } 5066 5067 /** 5068 * security_xfrm_state_pol_flow_match() - Check for a xfrm match 5069 * @x: xfrm state to match 5070 * @xp: xfrm policy to check for a match 5071 * @flic: flow to check for a match. 5072 * 5073 * Check @xp and @flic for a match with @x. 5074 * 5075 * Return: Returns 1 if there is a match. 5076 */ 5077 int security_xfrm_state_pol_flow_match(struct xfrm_state *x, 5078 struct xfrm_policy *xp, 5079 const struct flowi_common *flic) 5080 { 5081 struct lsm_static_call *scall; 5082 int rc = LSM_RET_DEFAULT(xfrm_state_pol_flow_match); 5083 5084 /* 5085 * Since this function is expected to return 0 or 1, the judgment 5086 * becomes difficult if multiple LSMs supply this call. Fortunately, 5087 * we can use the first LSM's judgment because currently only SELinux 5088 * supplies this call. 5089 * 5090 * For speed optimization, we explicitly break the loop rather than 5091 * using the macro 5092 */ 5093 lsm_for_each_hook(scall, xfrm_state_pol_flow_match) { 5094 rc = scall->hl->hook.xfrm_state_pol_flow_match(x, xp, flic); 5095 break; 5096 } 5097 return rc; 5098 } 5099 5100 /** 5101 * security_xfrm_decode_session() - Determine the xfrm secid for a packet 5102 * @skb: xfrm packet 5103 * @secid: secid 5104 * 5105 * Decode the packet in @skb and return the security label in @secid. 5106 * 5107 * Return: Return 0 if all xfrms used have the same secid. 5108 */ 5109 int security_xfrm_decode_session(struct sk_buff *skb, u32 *secid) 5110 { 5111 return call_int_hook(xfrm_decode_session, skb, secid, 1); 5112 } 5113 5114 void security_skb_classify_flow(struct sk_buff *skb, struct flowi_common *flic) 5115 { 5116 int rc = call_int_hook(xfrm_decode_session, skb, &flic->flowic_secid, 5117 0); 5118 5119 BUG_ON(rc); 5120 } 5121 EXPORT_SYMBOL(security_skb_classify_flow); 5122 #endif /* CONFIG_SECURITY_NETWORK_XFRM */ 5123 5124 #ifdef CONFIG_KEYS 5125 /** 5126 * security_key_alloc() - Allocate and initialize a kernel key LSM blob 5127 * @key: key 5128 * @cred: credentials 5129 * @flags: allocation flags 5130 * 5131 * Permit allocation of a key and assign security data. Note that key does not 5132 * have a serial number assigned at this point. 5133 * 5134 * Return: Return 0 if permission is granted, -ve error otherwise. 5135 */ 5136 int security_key_alloc(struct key *key, const struct cred *cred, 5137 unsigned long flags) 5138 { 5139 int rc = lsm_key_alloc(key); 5140 5141 if (unlikely(rc)) 5142 return rc; 5143 rc = call_int_hook(key_alloc, key, cred, flags); 5144 if (unlikely(rc)) 5145 security_key_free(key); 5146 return rc; 5147 } 5148 5149 /** 5150 * security_key_free() - Free a kernel key LSM blob 5151 * @key: key 5152 * 5153 * Notification of destruction; free security data. 5154 */ 5155 void security_key_free(struct key *key) 5156 { 5157 kfree(key->security); 5158 key->security = NULL; 5159 } 5160 5161 /** 5162 * security_key_permission() - Check if a kernel key operation is allowed 5163 * @key_ref: key reference 5164 * @cred: credentials of actor requesting access 5165 * @need_perm: requested permissions 5166 * 5167 * See whether a specific operational right is granted to a process on a key. 5168 * 5169 * Return: Return 0 if permission is granted, -ve error otherwise. 5170 */ 5171 int security_key_permission(key_ref_t key_ref, const struct cred *cred, 5172 enum key_need_perm need_perm) 5173 { 5174 return call_int_hook(key_permission, key_ref, cred, need_perm); 5175 } 5176 5177 /** 5178 * security_key_getsecurity() - Get the key's security label 5179 * @key: key 5180 * @buffer: security label buffer 5181 * 5182 * Get a textual representation of the security context attached to a key for 5183 * the purposes of honouring KEYCTL_GETSECURITY. This function allocates the 5184 * storage for the NUL-terminated string and the caller should free it. 5185 * 5186 * Return: Returns the length of @buffer (including terminating NUL) or -ve if 5187 * an error occurs. May also return 0 (and a NULL buffer pointer) if 5188 * there is no security label assigned to the key. 5189 */ 5190 int security_key_getsecurity(struct key *key, char **buffer) 5191 { 5192 *buffer = NULL; 5193 return call_int_hook(key_getsecurity, key, buffer); 5194 } 5195 5196 /** 5197 * security_key_post_create_or_update() - Notification of key create or update 5198 * @keyring: keyring to which the key is linked to 5199 * @key: created or updated key 5200 * @payload: data used to instantiate or update the key 5201 * @payload_len: length of payload 5202 * @flags: key flags 5203 * @create: flag indicating whether the key was created or updated 5204 * 5205 * Notify the caller of a key creation or update. 5206 */ 5207 void security_key_post_create_or_update(struct key *keyring, struct key *key, 5208 const void *payload, size_t payload_len, 5209 unsigned long flags, bool create) 5210 { 5211 call_void_hook(key_post_create_or_update, keyring, key, payload, 5212 payload_len, flags, create); 5213 } 5214 #endif /* CONFIG_KEYS */ 5215 5216 #ifdef CONFIG_AUDIT 5217 /** 5218 * security_audit_rule_init() - Allocate and init an LSM audit rule struct 5219 * @field: audit action 5220 * @op: rule operator 5221 * @rulestr: rule context 5222 * @lsmrule: receive buffer for audit rule struct 5223 * @gfp: GFP flag used for kmalloc 5224 * 5225 * Allocate and initialize an LSM audit rule structure. 5226 * 5227 * Return: Return 0 if @lsmrule has been successfully set, -EINVAL in case of 5228 * an invalid rule. 5229 */ 5230 int security_audit_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule, 5231 gfp_t gfp) 5232 { 5233 return call_int_hook(audit_rule_init, field, op, rulestr, lsmrule, gfp); 5234 } 5235 5236 /** 5237 * security_audit_rule_known() - Check if an audit rule contains LSM fields 5238 * @krule: audit rule 5239 * 5240 * Specifies whether given @krule contains any fields related to the current 5241 * LSM. 5242 * 5243 * Return: Returns 1 in case of relation found, 0 otherwise. 5244 */ 5245 int security_audit_rule_known(struct audit_krule *krule) 5246 { 5247 return call_int_hook(audit_rule_known, krule); 5248 } 5249 5250 /** 5251 * security_audit_rule_free() - Free an LSM audit rule struct 5252 * @lsmrule: audit rule struct 5253 * 5254 * Deallocate the LSM audit rule structure previously allocated by 5255 * audit_rule_init(). 5256 */ 5257 void security_audit_rule_free(void *lsmrule) 5258 { 5259 call_void_hook(audit_rule_free, lsmrule); 5260 } 5261 5262 /** 5263 * security_audit_rule_match() - Check if a label matches an audit rule 5264 * @prop: security label 5265 * @field: LSM audit field 5266 * @op: matching operator 5267 * @lsmrule: audit rule 5268 * 5269 * Determine if given @secid matches a rule previously approved by 5270 * security_audit_rule_known(). 5271 * 5272 * Return: Returns 1 if secid matches the rule, 0 if it does not, -ERRNO on 5273 * failure. 5274 */ 5275 int security_audit_rule_match(struct lsm_prop *prop, u32 field, u32 op, 5276 void *lsmrule) 5277 { 5278 return call_int_hook(audit_rule_match, prop, field, op, lsmrule); 5279 } 5280 #endif /* CONFIG_AUDIT */ 5281 5282 #ifdef CONFIG_BPF_SYSCALL 5283 /** 5284 * security_bpf() - Check if the bpf syscall operation is allowed 5285 * @cmd: command 5286 * @attr: bpf attribute 5287 * @size: size 5288 * @kernel: whether or not call originated from kernel 5289 * 5290 * Do a initial check for all bpf syscalls after the attribute is copied into 5291 * the kernel. The actual security module can implement their own rules to 5292 * check the specific cmd they need. 5293 * 5294 * Return: Returns 0 if permission is granted. 5295 */ 5296 int security_bpf(int cmd, union bpf_attr *attr, unsigned int size, bool kernel) 5297 { 5298 return call_int_hook(bpf, cmd, attr, size, kernel); 5299 } 5300 5301 /** 5302 * security_bpf_map() - Check if access to a bpf map is allowed 5303 * @map: bpf map 5304 * @fmode: mode 5305 * 5306 * Do a check when the kernel generates and returns a file descriptor for eBPF 5307 * maps. 5308 * 5309 * Return: Returns 0 if permission is granted. 5310 */ 5311 int security_bpf_map(struct bpf_map *map, fmode_t fmode) 5312 { 5313 return call_int_hook(bpf_map, map, fmode); 5314 } 5315 5316 /** 5317 * security_bpf_prog() - Check if access to a bpf program is allowed 5318 * @prog: bpf program 5319 * 5320 * Do a check when the kernel generates and returns a file descriptor for eBPF 5321 * programs. 5322 * 5323 * Return: Returns 0 if permission is granted. 5324 */ 5325 int security_bpf_prog(struct bpf_prog *prog) 5326 { 5327 return call_int_hook(bpf_prog, prog); 5328 } 5329 5330 /** 5331 * security_bpf_map_create() - Check if BPF map creation is allowed 5332 * @map: BPF map object 5333 * @attr: BPF syscall attributes used to create BPF map 5334 * @token: BPF token used to grant user access 5335 * @kernel: whether or not call originated from kernel 5336 * 5337 * Do a check when the kernel creates a new BPF map. This is also the 5338 * point where LSM blob is allocated for LSMs that need them. 5339 * 5340 * Return: Returns 0 on success, error on failure. 5341 */ 5342 int security_bpf_map_create(struct bpf_map *map, union bpf_attr *attr, 5343 struct bpf_token *token, bool kernel) 5344 { 5345 int rc; 5346 5347 rc = lsm_bpf_map_alloc(map); 5348 if (unlikely(rc)) 5349 return rc; 5350 5351 rc = call_int_hook(bpf_map_create, map, attr, token, kernel); 5352 if (unlikely(rc)) 5353 security_bpf_map_free(map); 5354 return rc; 5355 } 5356 5357 /** 5358 * security_bpf_prog_load() - Check if loading of BPF program is allowed 5359 * @prog: BPF program object 5360 * @attr: BPF syscall attributes used to create BPF program 5361 * @token: BPF token used to grant user access to BPF subsystem 5362 * @kernel: whether or not call originated from kernel 5363 * 5364 * Perform an access control check when the kernel loads a BPF program and 5365 * allocates associated BPF program object. This hook is also responsible for 5366 * allocating any required LSM state for the BPF program. 5367 * 5368 * Return: Returns 0 on success, error on failure. 5369 */ 5370 int security_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr, 5371 struct bpf_token *token, bool kernel) 5372 { 5373 int rc; 5374 5375 rc = lsm_bpf_prog_alloc(prog); 5376 if (unlikely(rc)) 5377 return rc; 5378 5379 rc = call_int_hook(bpf_prog_load, prog, attr, token, kernel); 5380 if (unlikely(rc)) 5381 security_bpf_prog_free(prog); 5382 return rc; 5383 } 5384 5385 /** 5386 * security_bpf_token_create() - Check if creating of BPF token is allowed 5387 * @token: BPF token object 5388 * @attr: BPF syscall attributes used to create BPF token 5389 * @path: path pointing to BPF FS mount point from which BPF token is created 5390 * 5391 * Do a check when the kernel instantiates a new BPF token object from BPF FS 5392 * instance. This is also the point where LSM blob can be allocated for LSMs. 5393 * 5394 * Return: Returns 0 on success, error on failure. 5395 */ 5396 int security_bpf_token_create(struct bpf_token *token, union bpf_attr *attr, 5397 const struct path *path) 5398 { 5399 int rc; 5400 5401 rc = lsm_bpf_token_alloc(token); 5402 if (unlikely(rc)) 5403 return rc; 5404 5405 rc = call_int_hook(bpf_token_create, token, attr, path); 5406 if (unlikely(rc)) 5407 security_bpf_token_free(token); 5408 return rc; 5409 } 5410 5411 /** 5412 * security_bpf_token_cmd() - Check if BPF token is allowed to delegate 5413 * requested BPF syscall command 5414 * @token: BPF token object 5415 * @cmd: BPF syscall command requested to be delegated by BPF token 5416 * 5417 * Do a check when the kernel decides whether provided BPF token should allow 5418 * delegation of requested BPF syscall command. 5419 * 5420 * Return: Returns 0 on success, error on failure. 5421 */ 5422 int security_bpf_token_cmd(const struct bpf_token *token, enum bpf_cmd cmd) 5423 { 5424 return call_int_hook(bpf_token_cmd, token, cmd); 5425 } 5426 5427 /** 5428 * security_bpf_token_capable() - Check if BPF token is allowed to delegate 5429 * requested BPF-related capability 5430 * @token: BPF token object 5431 * @cap: capabilities requested to be delegated by BPF token 5432 * 5433 * Do a check when the kernel decides whether provided BPF token should allow 5434 * delegation of requested BPF-related capabilities. 5435 * 5436 * Return: Returns 0 on success, error on failure. 5437 */ 5438 int security_bpf_token_capable(const struct bpf_token *token, int cap) 5439 { 5440 return call_int_hook(bpf_token_capable, token, cap); 5441 } 5442 5443 /** 5444 * security_bpf_map_free() - Free a bpf map's LSM blob 5445 * @map: bpf map 5446 * 5447 * Clean up the security information stored inside bpf map. 5448 */ 5449 void security_bpf_map_free(struct bpf_map *map) 5450 { 5451 call_void_hook(bpf_map_free, map); 5452 kfree(map->security); 5453 map->security = NULL; 5454 } 5455 5456 /** 5457 * security_bpf_prog_free() - Free a BPF program's LSM blob 5458 * @prog: BPF program struct 5459 * 5460 * Clean up the security information stored inside BPF program. 5461 */ 5462 void security_bpf_prog_free(struct bpf_prog *prog) 5463 { 5464 call_void_hook(bpf_prog_free, prog); 5465 kfree(prog->aux->security); 5466 prog->aux->security = NULL; 5467 } 5468 5469 /** 5470 * security_bpf_token_free() - Free a BPF token's LSM blob 5471 * @token: BPF token struct 5472 * 5473 * Clean up the security information stored inside BPF token. 5474 */ 5475 void security_bpf_token_free(struct bpf_token *token) 5476 { 5477 call_void_hook(bpf_token_free, token); 5478 kfree(token->security); 5479 token->security = NULL; 5480 } 5481 #endif /* CONFIG_BPF_SYSCALL */ 5482 5483 /** 5484 * security_locked_down() - Check if a kernel feature is allowed 5485 * @what: requested kernel feature 5486 * 5487 * Determine whether a kernel feature that potentially enables arbitrary code 5488 * execution in kernel space should be permitted. 5489 * 5490 * Return: Returns 0 if permission is granted. 5491 */ 5492 int security_locked_down(enum lockdown_reason what) 5493 { 5494 return call_int_hook(locked_down, what); 5495 } 5496 EXPORT_SYMBOL(security_locked_down); 5497 5498 /** 5499 * security_bdev_alloc() - Allocate a block device LSM blob 5500 * @bdev: block device 5501 * 5502 * Allocate and attach a security structure to @bdev->bd_security. The 5503 * security field is initialized to NULL when the bdev structure is 5504 * allocated. 5505 * 5506 * Return: Return 0 if operation was successful. 5507 */ 5508 int security_bdev_alloc(struct block_device *bdev) 5509 { 5510 int rc = 0; 5511 5512 rc = lsm_bdev_alloc(bdev); 5513 if (unlikely(rc)) 5514 return rc; 5515 5516 rc = call_int_hook(bdev_alloc_security, bdev); 5517 if (unlikely(rc)) 5518 security_bdev_free(bdev); 5519 5520 return rc; 5521 } 5522 EXPORT_SYMBOL(security_bdev_alloc); 5523 5524 /** 5525 * security_bdev_free() - Free a block device's LSM blob 5526 * @bdev: block device 5527 * 5528 * Deallocate the bdev security structure and set @bdev->bd_security to NULL. 5529 */ 5530 void security_bdev_free(struct block_device *bdev) 5531 { 5532 if (!bdev->bd_security) 5533 return; 5534 5535 call_void_hook(bdev_free_security, bdev); 5536 5537 kfree(bdev->bd_security); 5538 bdev->bd_security = NULL; 5539 } 5540 EXPORT_SYMBOL(security_bdev_free); 5541 5542 /** 5543 * security_bdev_setintegrity() - Set the device's integrity data 5544 * @bdev: block device 5545 * @type: type of integrity, e.g. hash digest, signature, etc 5546 * @value: the integrity value 5547 * @size: size of the integrity value 5548 * 5549 * Register a verified integrity measurement of a bdev with LSMs. 5550 * LSMs should free the previously saved data if @value is NULL. 5551 * Please note that the new hook should be invoked every time the security 5552 * information is updated to keep these data current. For example, in dm-verity, 5553 * if the mapping table is reloaded and configured to use a different dm-verity 5554 * target with a new roothash and signing information, the previously stored 5555 * data in the LSM blob will become obsolete. It is crucial to re-invoke the 5556 * hook to refresh these data and ensure they are up to date. This necessity 5557 * arises from the design of device-mapper, where a device-mapper device is 5558 * first created, and then targets are subsequently loaded into it. These 5559 * targets can be modified multiple times during the device's lifetime. 5560 * Therefore, while the LSM blob is allocated during the creation of the block 5561 * device, its actual contents are not initialized at this stage and can change 5562 * substantially over time. This includes alterations from data that the LSMs 5563 * 'trusts' to those they do not, making it essential to handle these changes 5564 * correctly. Failure to address this dynamic aspect could potentially allow 5565 * for bypassing LSM checks. 5566 * 5567 * Return: Returns 0 on success, negative values on failure. 5568 */ 5569 int security_bdev_setintegrity(struct block_device *bdev, 5570 enum lsm_integrity_type type, const void *value, 5571 size_t size) 5572 { 5573 return call_int_hook(bdev_setintegrity, bdev, type, value, size); 5574 } 5575 EXPORT_SYMBOL(security_bdev_setintegrity); 5576 5577 #ifdef CONFIG_PERF_EVENTS 5578 /** 5579 * security_perf_event_open() - Check if a perf event open is allowed 5580 * @type: type of event 5581 * 5582 * Check whether the @type of perf_event_open syscall is allowed. 5583 * 5584 * Return: Returns 0 if permission is granted. 5585 */ 5586 int security_perf_event_open(int type) 5587 { 5588 return call_int_hook(perf_event_open, type); 5589 } 5590 5591 /** 5592 * security_perf_event_alloc() - Allocate a perf event LSM blob 5593 * @event: perf event 5594 * 5595 * Allocate and save perf_event security info. 5596 * 5597 * Return: Returns 0 on success, error on failure. 5598 */ 5599 int security_perf_event_alloc(struct perf_event *event) 5600 { 5601 int rc; 5602 5603 rc = lsm_blob_alloc(&event->security, blob_sizes.lbs_perf_event, 5604 GFP_KERNEL); 5605 if (rc) 5606 return rc; 5607 5608 rc = call_int_hook(perf_event_alloc, event); 5609 if (rc) { 5610 kfree(event->security); 5611 event->security = NULL; 5612 } 5613 return rc; 5614 } 5615 5616 /** 5617 * security_perf_event_free() - Free a perf event LSM blob 5618 * @event: perf event 5619 * 5620 * Release (free) perf_event security info. 5621 */ 5622 void security_perf_event_free(struct perf_event *event) 5623 { 5624 kfree(event->security); 5625 event->security = NULL; 5626 } 5627 5628 /** 5629 * security_perf_event_read() - Check if reading a perf event label is allowed 5630 * @event: perf event 5631 * 5632 * Read perf_event security info if allowed. 5633 * 5634 * Return: Returns 0 if permission is granted. 5635 */ 5636 int security_perf_event_read(struct perf_event *event) 5637 { 5638 return call_int_hook(perf_event_read, event); 5639 } 5640 5641 /** 5642 * security_perf_event_write() - Check if writing a perf event label is allowed 5643 * @event: perf event 5644 * 5645 * Write perf_event security info if allowed. 5646 * 5647 * Return: Returns 0 if permission is granted. 5648 */ 5649 int security_perf_event_write(struct perf_event *event) 5650 { 5651 return call_int_hook(perf_event_write, event); 5652 } 5653 #endif /* CONFIG_PERF_EVENTS */ 5654 5655 #ifdef CONFIG_IO_URING 5656 /** 5657 * security_uring_override_creds() - Check if overriding creds is allowed 5658 * @new: new credentials 5659 * 5660 * Check if the current task, executing an io_uring operation, is allowed to 5661 * override it's credentials with @new. 5662 * 5663 * Return: Returns 0 if permission is granted. 5664 */ 5665 int security_uring_override_creds(const struct cred *new) 5666 { 5667 return call_int_hook(uring_override_creds, new); 5668 } 5669 5670 /** 5671 * security_uring_sqpoll() - Check if IORING_SETUP_SQPOLL is allowed 5672 * 5673 * Check whether the current task is allowed to spawn a io_uring polling thread 5674 * (IORING_SETUP_SQPOLL). 5675 * 5676 * Return: Returns 0 if permission is granted. 5677 */ 5678 int security_uring_sqpoll(void) 5679 { 5680 return call_int_hook(uring_sqpoll); 5681 } 5682 5683 /** 5684 * security_uring_cmd() - Check if a io_uring passthrough command is allowed 5685 * @ioucmd: command 5686 * 5687 * Check whether the file_operations uring_cmd is allowed to run. 5688 * 5689 * Return: Returns 0 if permission is granted. 5690 */ 5691 int security_uring_cmd(struct io_uring_cmd *ioucmd) 5692 { 5693 return call_int_hook(uring_cmd, ioucmd); 5694 } 5695 5696 /** 5697 * security_uring_allowed() - Check if io_uring_setup() is allowed 5698 * 5699 * Check whether the current task is allowed to call io_uring_setup(). 5700 * 5701 * Return: Returns 0 if permission is granted. 5702 */ 5703 int security_uring_allowed(void) 5704 { 5705 return call_int_hook(uring_allowed); 5706 } 5707 #endif /* CONFIG_IO_URING */ 5708 5709 /** 5710 * security_initramfs_populated() - Notify LSMs that initramfs has been loaded 5711 * 5712 * Tells the LSMs the initramfs has been unpacked into the rootfs. 5713 */ 5714 void security_initramfs_populated(void) 5715 { 5716 call_void_hook(initramfs_populated); 5717 } 5718