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