1 /* 2 * AppArmor security module 3 * 4 * This file contains AppArmor LSM hooks. 5 * 6 * Copyright (C) 1998-2008 Novell/SUSE 7 * Copyright 2009-2010 Canonical Ltd. 8 * 9 * This program is free software; you can redistribute it and/or 10 * modify it under the terms of the GNU General Public License as 11 * published by the Free Software Foundation, version 2 of the 12 * License. 13 */ 14 15 #include <linux/security.h> 16 #include <linux/moduleparam.h> 17 #include <linux/mm.h> 18 #include <linux/mman.h> 19 #include <linux/mount.h> 20 #include <linux/namei.h> 21 #include <linux/ptrace.h> 22 #include <linux/ctype.h> 23 #include <linux/sysctl.h> 24 #include <linux/audit.h> 25 #include <linux/user_namespace.h> 26 #include <net/sock.h> 27 28 #include "include/apparmor.h" 29 #include "include/apparmorfs.h" 30 #include "include/audit.h" 31 #include "include/capability.h" 32 #include "include/context.h" 33 #include "include/file.h" 34 #include "include/ipc.h" 35 #include "include/path.h" 36 #include "include/policy.h" 37 #include "include/procattr.h" 38 39 /* Flag indicating whether initialization completed */ 40 int apparmor_initialized __initdata; 41 42 /* 43 * LSM hook functions 44 */ 45 46 /* 47 * free the associated aa_task_cxt and put its profiles 48 */ 49 static void apparmor_cred_free(struct cred *cred) 50 { 51 aa_free_task_context(cred_cxt(cred)); 52 cred_cxt(cred) = NULL; 53 } 54 55 /* 56 * allocate the apparmor part of blank credentials 57 */ 58 static int apparmor_cred_alloc_blank(struct cred *cred, gfp_t gfp) 59 { 60 /* freed by apparmor_cred_free */ 61 struct aa_task_cxt *cxt = aa_alloc_task_context(gfp); 62 if (!cxt) 63 return -ENOMEM; 64 65 cred_cxt(cred) = cxt; 66 return 0; 67 } 68 69 /* 70 * prepare new aa_task_cxt for modification by prepare_cred block 71 */ 72 static int apparmor_cred_prepare(struct cred *new, const struct cred *old, 73 gfp_t gfp) 74 { 75 /* freed by apparmor_cred_free */ 76 struct aa_task_cxt *cxt = aa_alloc_task_context(gfp); 77 if (!cxt) 78 return -ENOMEM; 79 80 aa_dup_task_context(cxt, cred_cxt(old)); 81 cred_cxt(new) = cxt; 82 return 0; 83 } 84 85 /* 86 * transfer the apparmor data to a blank set of creds 87 */ 88 static void apparmor_cred_transfer(struct cred *new, const struct cred *old) 89 { 90 const struct aa_task_cxt *old_cxt = cred_cxt(old); 91 struct aa_task_cxt *new_cxt = cred_cxt(new); 92 93 aa_dup_task_context(new_cxt, old_cxt); 94 } 95 96 static int apparmor_ptrace_access_check(struct task_struct *child, 97 unsigned int mode) 98 { 99 int error = cap_ptrace_access_check(child, mode); 100 if (error) 101 return error; 102 103 return aa_ptrace(current, child, mode); 104 } 105 106 static int apparmor_ptrace_traceme(struct task_struct *parent) 107 { 108 int error = cap_ptrace_traceme(parent); 109 if (error) 110 return error; 111 112 return aa_ptrace(parent, current, PTRACE_MODE_ATTACH); 113 } 114 115 /* Derived from security/commoncap.c:cap_capget */ 116 static int apparmor_capget(struct task_struct *target, kernel_cap_t *effective, 117 kernel_cap_t *inheritable, kernel_cap_t *permitted) 118 { 119 struct aa_profile *profile; 120 const struct cred *cred; 121 122 rcu_read_lock(); 123 cred = __task_cred(target); 124 profile = aa_cred_profile(cred); 125 126 *effective = cred->cap_effective; 127 *inheritable = cred->cap_inheritable; 128 *permitted = cred->cap_permitted; 129 130 if (!unconfined(profile) && !COMPLAIN_MODE(profile)) { 131 *effective = cap_intersect(*effective, profile->caps.allow); 132 *permitted = cap_intersect(*permitted, profile->caps.allow); 133 } 134 rcu_read_unlock(); 135 136 return 0; 137 } 138 139 static int apparmor_capable(const struct cred *cred, struct user_namespace *ns, 140 int cap, int audit) 141 { 142 struct aa_profile *profile; 143 /* cap_capable returns 0 on success, else -EPERM */ 144 int error = cap_capable(cred, ns, cap, audit); 145 if (!error) { 146 profile = aa_cred_profile(cred); 147 if (!unconfined(profile)) 148 error = aa_capable(current, profile, cap, audit); 149 } 150 return error; 151 } 152 153 /** 154 * common_perm - basic common permission check wrapper fn for paths 155 * @op: operation being checked 156 * @path: path to check permission of (NOT NULL) 157 * @mask: requested permissions mask 158 * @cond: conditional info for the permission request (NOT NULL) 159 * 160 * Returns: %0 else error code if error or permission denied 161 */ 162 static int common_perm(int op, struct path *path, u32 mask, 163 struct path_cond *cond) 164 { 165 struct aa_profile *profile; 166 int error = 0; 167 168 profile = __aa_current_profile(); 169 if (!unconfined(profile)) 170 error = aa_path_perm(op, profile, path, 0, mask, cond); 171 172 return error; 173 } 174 175 /** 176 * common_perm_dir_dentry - common permission wrapper when path is dir, dentry 177 * @op: operation being checked 178 * @dir: directory of the dentry (NOT NULL) 179 * @dentry: dentry to check (NOT NULL) 180 * @mask: requested permissions mask 181 * @cond: conditional info for the permission request (NOT NULL) 182 * 183 * Returns: %0 else error code if error or permission denied 184 */ 185 static int common_perm_dir_dentry(int op, struct path *dir, 186 struct dentry *dentry, u32 mask, 187 struct path_cond *cond) 188 { 189 struct path path = { dir->mnt, dentry }; 190 191 return common_perm(op, &path, mask, cond); 192 } 193 194 /** 195 * common_perm_mnt_dentry - common permission wrapper when mnt, dentry 196 * @op: operation being checked 197 * @mnt: mount point of dentry (NOT NULL) 198 * @dentry: dentry to check (NOT NULL) 199 * @mask: requested permissions mask 200 * 201 * Returns: %0 else error code if error or permission denied 202 */ 203 static int common_perm_mnt_dentry(int op, struct vfsmount *mnt, 204 struct dentry *dentry, u32 mask) 205 { 206 struct path path = { mnt, dentry }; 207 struct path_cond cond = { dentry->d_inode->i_uid, 208 dentry->d_inode->i_mode 209 }; 210 211 return common_perm(op, &path, mask, &cond); 212 } 213 214 /** 215 * common_perm_rm - common permission wrapper for operations doing rm 216 * @op: operation being checked 217 * @dir: directory that the dentry is in (NOT NULL) 218 * @dentry: dentry being rm'd (NOT NULL) 219 * @mask: requested permission mask 220 * 221 * Returns: %0 else error code if error or permission denied 222 */ 223 static int common_perm_rm(int op, struct path *dir, 224 struct dentry *dentry, u32 mask) 225 { 226 struct inode *inode = dentry->d_inode; 227 struct path_cond cond = { }; 228 229 if (!inode || !dir->mnt || !mediated_filesystem(inode)) 230 return 0; 231 232 cond.uid = inode->i_uid; 233 cond.mode = inode->i_mode; 234 235 return common_perm_dir_dentry(op, dir, dentry, mask, &cond); 236 } 237 238 /** 239 * common_perm_create - common permission wrapper for operations doing create 240 * @op: operation being checked 241 * @dir: directory that dentry will be created in (NOT NULL) 242 * @dentry: dentry to create (NOT NULL) 243 * @mask: request permission mask 244 * @mode: created file mode 245 * 246 * Returns: %0 else error code if error or permission denied 247 */ 248 static int common_perm_create(int op, struct path *dir, struct dentry *dentry, 249 u32 mask, umode_t mode) 250 { 251 struct path_cond cond = { current_fsuid(), mode }; 252 253 if (!dir->mnt || !mediated_filesystem(dir->dentry->d_inode)) 254 return 0; 255 256 return common_perm_dir_dentry(op, dir, dentry, mask, &cond); 257 } 258 259 static int apparmor_path_unlink(struct path *dir, struct dentry *dentry) 260 { 261 return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE); 262 } 263 264 static int apparmor_path_mkdir(struct path *dir, struct dentry *dentry, 265 umode_t mode) 266 { 267 return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE, 268 S_IFDIR); 269 } 270 271 static int apparmor_path_rmdir(struct path *dir, struct dentry *dentry) 272 { 273 return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE); 274 } 275 276 static int apparmor_path_mknod(struct path *dir, struct dentry *dentry, 277 umode_t mode, unsigned int dev) 278 { 279 return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode); 280 } 281 282 static int apparmor_path_truncate(struct path *path) 283 { 284 struct path_cond cond = { path->dentry->d_inode->i_uid, 285 path->dentry->d_inode->i_mode 286 }; 287 288 if (!path->mnt || !mediated_filesystem(path->dentry->d_inode)) 289 return 0; 290 291 return common_perm(OP_TRUNC, path, MAY_WRITE | AA_MAY_META_WRITE, 292 &cond); 293 } 294 295 static int apparmor_path_symlink(struct path *dir, struct dentry *dentry, 296 const char *old_name) 297 { 298 return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE, 299 S_IFLNK); 300 } 301 302 static int apparmor_path_link(struct dentry *old_dentry, struct path *new_dir, 303 struct dentry *new_dentry) 304 { 305 struct aa_profile *profile; 306 int error = 0; 307 308 if (!mediated_filesystem(old_dentry->d_inode)) 309 return 0; 310 311 profile = aa_current_profile(); 312 if (!unconfined(profile)) 313 error = aa_path_link(profile, old_dentry, new_dir, new_dentry); 314 return error; 315 } 316 317 static int apparmor_path_rename(struct path *old_dir, struct dentry *old_dentry, 318 struct path *new_dir, struct dentry *new_dentry) 319 { 320 struct aa_profile *profile; 321 int error = 0; 322 323 if (!mediated_filesystem(old_dentry->d_inode)) 324 return 0; 325 326 profile = aa_current_profile(); 327 if (!unconfined(profile)) { 328 struct path old_path = { old_dir->mnt, old_dentry }; 329 struct path new_path = { new_dir->mnt, new_dentry }; 330 struct path_cond cond = { old_dentry->d_inode->i_uid, 331 old_dentry->d_inode->i_mode 332 }; 333 334 error = aa_path_perm(OP_RENAME_SRC, profile, &old_path, 0, 335 MAY_READ | AA_MAY_META_READ | MAY_WRITE | 336 AA_MAY_META_WRITE | AA_MAY_DELETE, 337 &cond); 338 if (!error) 339 error = aa_path_perm(OP_RENAME_DEST, profile, &new_path, 340 0, MAY_WRITE | AA_MAY_META_WRITE | 341 AA_MAY_CREATE, &cond); 342 343 } 344 return error; 345 } 346 347 static int apparmor_path_chmod(struct path *path, umode_t mode) 348 { 349 if (!mediated_filesystem(path->dentry->d_inode)) 350 return 0; 351 352 return common_perm_mnt_dentry(OP_CHMOD, path->mnt, path->dentry, AA_MAY_CHMOD); 353 } 354 355 static int apparmor_path_chown(struct path *path, kuid_t uid, kgid_t gid) 356 { 357 struct path_cond cond = { path->dentry->d_inode->i_uid, 358 path->dentry->d_inode->i_mode 359 }; 360 361 if (!mediated_filesystem(path->dentry->d_inode)) 362 return 0; 363 364 return common_perm(OP_CHOWN, path, AA_MAY_CHOWN, &cond); 365 } 366 367 static int apparmor_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) 368 { 369 if (!mediated_filesystem(dentry->d_inode)) 370 return 0; 371 372 return common_perm_mnt_dentry(OP_GETATTR, mnt, dentry, 373 AA_MAY_META_READ); 374 } 375 376 static int apparmor_file_open(struct file *file, const struct cred *cred) 377 { 378 struct aa_file_cxt *fcxt = file->f_security; 379 struct aa_profile *profile; 380 int error = 0; 381 382 if (!mediated_filesystem(file_inode(file))) 383 return 0; 384 385 /* If in exec, permission is handled by bprm hooks. 386 * Cache permissions granted by the previous exec check, with 387 * implicit read and executable mmap which are required to 388 * actually execute the image. 389 */ 390 if (current->in_execve) { 391 fcxt->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP; 392 return 0; 393 } 394 395 profile = aa_cred_profile(cred); 396 if (!unconfined(profile)) { 397 struct inode *inode = file_inode(file); 398 struct path_cond cond = { inode->i_uid, inode->i_mode }; 399 400 error = aa_path_perm(OP_OPEN, profile, &file->f_path, 0, 401 aa_map_file_to_perms(file), &cond); 402 /* todo cache full allowed permissions set and state */ 403 fcxt->allow = aa_map_file_to_perms(file); 404 } 405 406 return error; 407 } 408 409 static int apparmor_file_alloc_security(struct file *file) 410 { 411 /* freed by apparmor_file_free_security */ 412 file->f_security = aa_alloc_file_context(GFP_KERNEL); 413 if (!file->f_security) 414 return -ENOMEM; 415 return 0; 416 417 } 418 419 static void apparmor_file_free_security(struct file *file) 420 { 421 struct aa_file_cxt *cxt = file->f_security; 422 423 aa_free_file_context(cxt); 424 } 425 426 static int common_file_perm(int op, struct file *file, u32 mask) 427 { 428 struct aa_file_cxt *fcxt = file->f_security; 429 struct aa_profile *profile, *fprofile = aa_cred_profile(file->f_cred); 430 int error = 0; 431 432 BUG_ON(!fprofile); 433 434 if (!file->f_path.mnt || 435 !mediated_filesystem(file_inode(file))) 436 return 0; 437 438 profile = __aa_current_profile(); 439 440 /* revalidate access, if task is unconfined, or the cached cred 441 * doesn't match or if the request is for more permissions than 442 * was granted. 443 * 444 * Note: the test for !unconfined(fprofile) is to handle file 445 * delegation from unconfined tasks 446 */ 447 if (!unconfined(profile) && !unconfined(fprofile) && 448 ((fprofile != profile) || (mask & ~fcxt->allow))) 449 error = aa_file_perm(op, profile, file, mask); 450 451 return error; 452 } 453 454 static int apparmor_file_permission(struct file *file, int mask) 455 { 456 return common_file_perm(OP_FPERM, file, mask); 457 } 458 459 static int apparmor_file_lock(struct file *file, unsigned int cmd) 460 { 461 u32 mask = AA_MAY_LOCK; 462 463 if (cmd == F_WRLCK) 464 mask |= MAY_WRITE; 465 466 return common_file_perm(OP_FLOCK, file, mask); 467 } 468 469 static int common_mmap(int op, struct file *file, unsigned long prot, 470 unsigned long flags) 471 { 472 int mask = 0; 473 474 if (!file || !file->f_security) 475 return 0; 476 477 if (prot & PROT_READ) 478 mask |= MAY_READ; 479 /* 480 * Private mappings don't require write perms since they don't 481 * write back to the files 482 */ 483 if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE)) 484 mask |= MAY_WRITE; 485 if (prot & PROT_EXEC) 486 mask |= AA_EXEC_MMAP; 487 488 return common_file_perm(op, file, mask); 489 } 490 491 static int apparmor_mmap_file(struct file *file, unsigned long reqprot, 492 unsigned long prot, unsigned long flags) 493 { 494 return common_mmap(OP_FMMAP, file, prot, flags); 495 } 496 497 static int apparmor_file_mprotect(struct vm_area_struct *vma, 498 unsigned long reqprot, unsigned long prot) 499 { 500 return common_mmap(OP_FMPROT, vma->vm_file, prot, 501 !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0); 502 } 503 504 static int apparmor_getprocattr(struct task_struct *task, char *name, 505 char **value) 506 { 507 int error = -ENOENT; 508 /* released below */ 509 const struct cred *cred = get_task_cred(task); 510 struct aa_task_cxt *cxt = cred_cxt(cred); 511 struct aa_profile *profile = NULL; 512 513 if (strcmp(name, "current") == 0) 514 profile = aa_get_newest_profile(cxt->profile); 515 else if (strcmp(name, "prev") == 0 && cxt->previous) 516 profile = aa_get_newest_profile(cxt->previous); 517 else if (strcmp(name, "exec") == 0 && cxt->onexec) 518 profile = aa_get_newest_profile(cxt->onexec); 519 else 520 error = -EINVAL; 521 522 if (profile) 523 error = aa_getprocattr(profile, value); 524 525 aa_put_profile(profile); 526 put_cred(cred); 527 528 return error; 529 } 530 531 static int apparmor_setprocattr(struct task_struct *task, char *name, 532 void *value, size_t size) 533 { 534 struct common_audit_data sa; 535 struct apparmor_audit_data aad = {0,}; 536 char *command, *args = value; 537 size_t arg_size; 538 int error; 539 540 if (size == 0) 541 return -EINVAL; 542 /* args points to a PAGE_SIZE buffer, AppArmor requires that 543 * the buffer must be null terminated or have size <= PAGE_SIZE -1 544 * so that AppArmor can null terminate them 545 */ 546 if (args[size - 1] != '\0') { 547 if (size == PAGE_SIZE) 548 return -EINVAL; 549 args[size] = '\0'; 550 } 551 552 /* task can only write its own attributes */ 553 if (current != task) 554 return -EACCES; 555 556 args = value; 557 args = strim(args); 558 command = strsep(&args, " "); 559 if (!args) 560 return -EINVAL; 561 args = skip_spaces(args); 562 if (!*args) 563 return -EINVAL; 564 565 arg_size = size - (args - (char *) value); 566 if (strcmp(name, "current") == 0) { 567 if (strcmp(command, "changehat") == 0) { 568 error = aa_setprocattr_changehat(args, arg_size, 569 !AA_DO_TEST); 570 } else if (strcmp(command, "permhat") == 0) { 571 error = aa_setprocattr_changehat(args, arg_size, 572 AA_DO_TEST); 573 } else if (strcmp(command, "changeprofile") == 0) { 574 error = aa_setprocattr_changeprofile(args, !AA_ONEXEC, 575 !AA_DO_TEST); 576 } else if (strcmp(command, "permprofile") == 0) { 577 error = aa_setprocattr_changeprofile(args, !AA_ONEXEC, 578 AA_DO_TEST); 579 } else 580 goto fail; 581 } else if (strcmp(name, "exec") == 0) { 582 if (strcmp(command, "exec") == 0) 583 error = aa_setprocattr_changeprofile(args, AA_ONEXEC, 584 !AA_DO_TEST); 585 else 586 goto fail; 587 } else 588 /* only support the "current" and "exec" process attributes */ 589 return -EINVAL; 590 591 if (!error) 592 error = size; 593 return error; 594 595 fail: 596 sa.type = LSM_AUDIT_DATA_NONE; 597 sa.aad = &aad; 598 aad.profile = aa_current_profile(); 599 aad.op = OP_SETPROCATTR; 600 aad.info = name; 601 aad.error = -EINVAL; 602 aa_audit_msg(AUDIT_APPARMOR_DENIED, &sa, NULL); 603 return -EINVAL; 604 } 605 606 static int apparmor_task_setrlimit(struct task_struct *task, 607 unsigned int resource, struct rlimit *new_rlim) 608 { 609 struct aa_profile *profile = __aa_current_profile(); 610 int error = 0; 611 612 if (!unconfined(profile)) 613 error = aa_task_setrlimit(profile, task, resource, new_rlim); 614 615 return error; 616 } 617 618 static struct security_operations apparmor_ops = { 619 .name = "apparmor", 620 621 .ptrace_access_check = apparmor_ptrace_access_check, 622 .ptrace_traceme = apparmor_ptrace_traceme, 623 .capget = apparmor_capget, 624 .capable = apparmor_capable, 625 626 .path_link = apparmor_path_link, 627 .path_unlink = apparmor_path_unlink, 628 .path_symlink = apparmor_path_symlink, 629 .path_mkdir = apparmor_path_mkdir, 630 .path_rmdir = apparmor_path_rmdir, 631 .path_mknod = apparmor_path_mknod, 632 .path_rename = apparmor_path_rename, 633 .path_chmod = apparmor_path_chmod, 634 .path_chown = apparmor_path_chown, 635 .path_truncate = apparmor_path_truncate, 636 .inode_getattr = apparmor_inode_getattr, 637 638 .file_open = apparmor_file_open, 639 .file_permission = apparmor_file_permission, 640 .file_alloc_security = apparmor_file_alloc_security, 641 .file_free_security = apparmor_file_free_security, 642 .mmap_file = apparmor_mmap_file, 643 .mmap_addr = cap_mmap_addr, 644 .file_mprotect = apparmor_file_mprotect, 645 .file_lock = apparmor_file_lock, 646 647 .getprocattr = apparmor_getprocattr, 648 .setprocattr = apparmor_setprocattr, 649 650 .cred_alloc_blank = apparmor_cred_alloc_blank, 651 .cred_free = apparmor_cred_free, 652 .cred_prepare = apparmor_cred_prepare, 653 .cred_transfer = apparmor_cred_transfer, 654 655 .bprm_set_creds = apparmor_bprm_set_creds, 656 .bprm_committing_creds = apparmor_bprm_committing_creds, 657 .bprm_committed_creds = apparmor_bprm_committed_creds, 658 .bprm_secureexec = apparmor_bprm_secureexec, 659 660 .task_setrlimit = apparmor_task_setrlimit, 661 }; 662 663 /* 664 * AppArmor sysfs module parameters 665 */ 666 667 static int param_set_aabool(const char *val, const struct kernel_param *kp); 668 static int param_get_aabool(char *buffer, const struct kernel_param *kp); 669 #define param_check_aabool param_check_bool 670 static struct kernel_param_ops param_ops_aabool = { 671 .flags = KERNEL_PARAM_FL_NOARG, 672 .set = param_set_aabool, 673 .get = param_get_aabool 674 }; 675 676 static int param_set_aauint(const char *val, const struct kernel_param *kp); 677 static int param_get_aauint(char *buffer, const struct kernel_param *kp); 678 #define param_check_aauint param_check_uint 679 static struct kernel_param_ops param_ops_aauint = { 680 .set = param_set_aauint, 681 .get = param_get_aauint 682 }; 683 684 static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp); 685 static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp); 686 #define param_check_aalockpolicy param_check_bool 687 static struct kernel_param_ops param_ops_aalockpolicy = { 688 .flags = KERNEL_PARAM_FL_NOARG, 689 .set = param_set_aalockpolicy, 690 .get = param_get_aalockpolicy 691 }; 692 693 static int param_set_audit(const char *val, struct kernel_param *kp); 694 static int param_get_audit(char *buffer, struct kernel_param *kp); 695 696 static int param_set_mode(const char *val, struct kernel_param *kp); 697 static int param_get_mode(char *buffer, struct kernel_param *kp); 698 699 /* Flag values, also controllable via /sys/module/apparmor/parameters 700 * We define special types as we want to do additional mediation. 701 */ 702 703 /* AppArmor global enforcement switch - complain, enforce, kill */ 704 enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE; 705 module_param_call(mode, param_set_mode, param_get_mode, 706 &aa_g_profile_mode, S_IRUSR | S_IWUSR); 707 708 /* Debug mode */ 709 bool aa_g_debug; 710 module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR); 711 712 /* Audit mode */ 713 enum audit_mode aa_g_audit; 714 module_param_call(audit, param_set_audit, param_get_audit, 715 &aa_g_audit, S_IRUSR | S_IWUSR); 716 717 /* Determines if audit header is included in audited messages. This 718 * provides more context if the audit daemon is not running 719 */ 720 bool aa_g_audit_header = 1; 721 module_param_named(audit_header, aa_g_audit_header, aabool, 722 S_IRUSR | S_IWUSR); 723 724 /* lock out loading/removal of policy 725 * TODO: add in at boot loading of policy, which is the only way to 726 * load policy, if lock_policy is set 727 */ 728 bool aa_g_lock_policy; 729 module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy, 730 S_IRUSR | S_IWUSR); 731 732 /* Syscall logging mode */ 733 bool aa_g_logsyscall; 734 module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR); 735 736 /* Maximum pathname length before accesses will start getting rejected */ 737 unsigned int aa_g_path_max = 2 * PATH_MAX; 738 module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR | S_IWUSR); 739 740 /* Determines how paranoid loading of policy is and how much verification 741 * on the loaded policy is done. 742 */ 743 bool aa_g_paranoid_load = 1; 744 module_param_named(paranoid_load, aa_g_paranoid_load, aabool, 745 S_IRUSR | S_IWUSR); 746 747 /* Boot time disable flag */ 748 static bool apparmor_enabled = CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE; 749 module_param_named(enabled, apparmor_enabled, bool, S_IRUGO); 750 751 static int __init apparmor_enabled_setup(char *str) 752 { 753 unsigned long enabled; 754 int error = strict_strtoul(str, 0, &enabled); 755 if (!error) 756 apparmor_enabled = enabled ? 1 : 0; 757 return 1; 758 } 759 760 __setup("apparmor=", apparmor_enabled_setup); 761 762 /* set global flag turning off the ability to load policy */ 763 static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp) 764 { 765 if (!capable(CAP_MAC_ADMIN)) 766 return -EPERM; 767 if (aa_g_lock_policy) 768 return -EACCES; 769 return param_set_bool(val, kp); 770 } 771 772 static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp) 773 { 774 if (!capable(CAP_MAC_ADMIN)) 775 return -EPERM; 776 return param_get_bool(buffer, kp); 777 } 778 779 static int param_set_aabool(const char *val, const struct kernel_param *kp) 780 { 781 if (!capable(CAP_MAC_ADMIN)) 782 return -EPERM; 783 return param_set_bool(val, kp); 784 } 785 786 static int param_get_aabool(char *buffer, const struct kernel_param *kp) 787 { 788 if (!capable(CAP_MAC_ADMIN)) 789 return -EPERM; 790 return param_get_bool(buffer, kp); 791 } 792 793 static int param_set_aauint(const char *val, const struct kernel_param *kp) 794 { 795 if (!capable(CAP_MAC_ADMIN)) 796 return -EPERM; 797 return param_set_uint(val, kp); 798 } 799 800 static int param_get_aauint(char *buffer, const struct kernel_param *kp) 801 { 802 if (!capable(CAP_MAC_ADMIN)) 803 return -EPERM; 804 return param_get_uint(buffer, kp); 805 } 806 807 static int param_get_audit(char *buffer, struct kernel_param *kp) 808 { 809 if (!capable(CAP_MAC_ADMIN)) 810 return -EPERM; 811 812 if (!apparmor_enabled) 813 return -EINVAL; 814 815 return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]); 816 } 817 818 static int param_set_audit(const char *val, struct kernel_param *kp) 819 { 820 int i; 821 if (!capable(CAP_MAC_ADMIN)) 822 return -EPERM; 823 824 if (!apparmor_enabled) 825 return -EINVAL; 826 827 if (!val) 828 return -EINVAL; 829 830 for (i = 0; i < AUDIT_MAX_INDEX; i++) { 831 if (strcmp(val, audit_mode_names[i]) == 0) { 832 aa_g_audit = i; 833 return 0; 834 } 835 } 836 837 return -EINVAL; 838 } 839 840 static int param_get_mode(char *buffer, struct kernel_param *kp) 841 { 842 if (!capable(CAP_MAC_ADMIN)) 843 return -EPERM; 844 845 if (!apparmor_enabled) 846 return -EINVAL; 847 848 return sprintf(buffer, "%s", aa_profile_mode_names[aa_g_profile_mode]); 849 } 850 851 static int param_set_mode(const char *val, struct kernel_param *kp) 852 { 853 int i; 854 if (!capable(CAP_MAC_ADMIN)) 855 return -EPERM; 856 857 if (!apparmor_enabled) 858 return -EINVAL; 859 860 if (!val) 861 return -EINVAL; 862 863 for (i = 0; i < APPARMOR_MODE_NAMES_MAX_INDEX; i++) { 864 if (strcmp(val, aa_profile_mode_names[i]) == 0) { 865 aa_g_profile_mode = i; 866 return 0; 867 } 868 } 869 870 return -EINVAL; 871 } 872 873 /* 874 * AppArmor init functions 875 */ 876 877 /** 878 * set_init_cxt - set a task context and profile on the first task. 879 * 880 * TODO: allow setting an alternate profile than unconfined 881 */ 882 static int __init set_init_cxt(void) 883 { 884 struct cred *cred = (struct cred *)current->real_cred; 885 struct aa_task_cxt *cxt; 886 887 cxt = aa_alloc_task_context(GFP_KERNEL); 888 if (!cxt) 889 return -ENOMEM; 890 891 cxt->profile = aa_get_profile(root_ns->unconfined); 892 cred_cxt(cred) = cxt; 893 894 return 0; 895 } 896 897 static int __init apparmor_init(void) 898 { 899 int error; 900 901 if (!apparmor_enabled || !security_module_enable(&apparmor_ops)) { 902 aa_info_message("AppArmor disabled by boot time parameter"); 903 apparmor_enabled = 0; 904 return 0; 905 } 906 907 error = aa_alloc_root_ns(); 908 if (error) { 909 AA_ERROR("Unable to allocate default profile namespace\n"); 910 goto alloc_out; 911 } 912 913 error = set_init_cxt(); 914 if (error) { 915 AA_ERROR("Failed to set context on init task\n"); 916 goto register_security_out; 917 } 918 919 error = register_security(&apparmor_ops); 920 if (error) { 921 struct cred *cred = (struct cred *)current->real_cred; 922 aa_free_task_context(cred_cxt(cred)); 923 cred_cxt(cred) = NULL; 924 AA_ERROR("Unable to register AppArmor\n"); 925 goto register_security_out; 926 } 927 928 /* Report that AppArmor successfully initialized */ 929 apparmor_initialized = 1; 930 if (aa_g_profile_mode == APPARMOR_COMPLAIN) 931 aa_info_message("AppArmor initialized: complain mode enabled"); 932 else if (aa_g_profile_mode == APPARMOR_KILL) 933 aa_info_message("AppArmor initialized: kill mode enabled"); 934 else 935 aa_info_message("AppArmor initialized"); 936 937 return error; 938 939 register_security_out: 940 aa_free_root_ns(); 941 942 alloc_out: 943 aa_destroy_aafs(); 944 945 apparmor_enabled = 0; 946 return error; 947 } 948 949 security_initcall(apparmor_init); 950