John Johansen | b5e95b4 | 2010-07-29 14:48:07 -0700 | [diff] [blame] | 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 <net/sock.h> |
| 26 | |
| 27 | #include "include/apparmor.h" |
| 28 | #include "include/apparmorfs.h" |
| 29 | #include "include/audit.h" |
| 30 | #include "include/capability.h" |
| 31 | #include "include/context.h" |
| 32 | #include "include/file.h" |
| 33 | #include "include/ipc.h" |
| 34 | #include "include/path.h" |
| 35 | #include "include/policy.h" |
| 36 | #include "include/procattr.h" |
| 37 | |
| 38 | /* Flag indicating whether initialization completed */ |
| 39 | int apparmor_initialized __initdata; |
| 40 | |
| 41 | /* |
| 42 | * LSM hook functions |
| 43 | */ |
| 44 | |
| 45 | /* |
| 46 | * free the associated aa_task_cxt and put its profiles |
| 47 | */ |
| 48 | static void apparmor_cred_free(struct cred *cred) |
| 49 | { |
| 50 | aa_free_task_context(cred->security); |
| 51 | cred->security = NULL; |
| 52 | } |
| 53 | |
| 54 | /* |
| 55 | * allocate the apparmor part of blank credentials |
| 56 | */ |
| 57 | static int apparmor_cred_alloc_blank(struct cred *cred, gfp_t gfp) |
| 58 | { |
| 59 | /* freed by apparmor_cred_free */ |
| 60 | struct aa_task_cxt *cxt = aa_alloc_task_context(gfp); |
| 61 | if (!cxt) |
| 62 | return -ENOMEM; |
| 63 | |
| 64 | cred->security = cxt; |
| 65 | return 0; |
| 66 | } |
| 67 | |
| 68 | /* |
| 69 | * prepare new aa_task_cxt for modification by prepare_cred block |
| 70 | */ |
| 71 | static int apparmor_cred_prepare(struct cred *new, const struct cred *old, |
| 72 | gfp_t gfp) |
| 73 | { |
| 74 | /* freed by apparmor_cred_free */ |
| 75 | struct aa_task_cxt *cxt = aa_alloc_task_context(gfp); |
| 76 | if (!cxt) |
| 77 | return -ENOMEM; |
| 78 | |
| 79 | aa_dup_task_context(cxt, old->security); |
| 80 | new->security = cxt; |
| 81 | return 0; |
| 82 | } |
| 83 | |
| 84 | /* |
| 85 | * transfer the apparmor data to a blank set of creds |
| 86 | */ |
| 87 | static void apparmor_cred_transfer(struct cred *new, const struct cred *old) |
| 88 | { |
| 89 | const struct aa_task_cxt *old_cxt = old->security; |
| 90 | struct aa_task_cxt *new_cxt = new->security; |
| 91 | |
| 92 | aa_dup_task_context(new_cxt, old_cxt); |
| 93 | } |
| 94 | |
| 95 | static int apparmor_ptrace_access_check(struct task_struct *child, |
| 96 | unsigned int mode) |
| 97 | { |
| 98 | int error = cap_ptrace_access_check(child, mode); |
| 99 | if (error) |
| 100 | return error; |
| 101 | |
| 102 | return aa_ptrace(current, child, mode); |
| 103 | } |
| 104 | |
| 105 | static int apparmor_ptrace_traceme(struct task_struct *parent) |
| 106 | { |
| 107 | int error = cap_ptrace_traceme(parent); |
| 108 | if (error) |
| 109 | return error; |
| 110 | |
| 111 | return aa_ptrace(parent, current, PTRACE_MODE_ATTACH); |
| 112 | } |
| 113 | |
| 114 | /* Derived from security/commoncap.c:cap_capget */ |
| 115 | static int apparmor_capget(struct task_struct *target, kernel_cap_t *effective, |
| 116 | kernel_cap_t *inheritable, kernel_cap_t *permitted) |
| 117 | { |
| 118 | struct aa_profile *profile; |
| 119 | const struct cred *cred; |
| 120 | |
| 121 | rcu_read_lock(); |
| 122 | cred = __task_cred(target); |
| 123 | profile = aa_cred_profile(cred); |
| 124 | |
| 125 | *effective = cred->cap_effective; |
| 126 | *inheritable = cred->cap_inheritable; |
| 127 | *permitted = cred->cap_permitted; |
| 128 | |
| 129 | if (!unconfined(profile)) { |
| 130 | *effective = cap_intersect(*effective, profile->caps.allow); |
| 131 | *permitted = cap_intersect(*permitted, profile->caps.allow); |
| 132 | } |
| 133 | rcu_read_unlock(); |
| 134 | |
| 135 | return 0; |
| 136 | } |
| 137 | |
| 138 | static int apparmor_capable(struct task_struct *task, const struct cred *cred, |
| 139 | int cap, int audit) |
| 140 | { |
| 141 | struct aa_profile *profile; |
| 142 | /* cap_capable returns 0 on success, else -EPERM */ |
| 143 | int error = cap_capable(task, cred, cap, audit); |
| 144 | if (!error) { |
| 145 | profile = aa_cred_profile(cred); |
| 146 | if (!unconfined(profile)) |
| 147 | error = aa_capable(task, profile, cap, audit); |
| 148 | } |
| 149 | return error; |
| 150 | } |
| 151 | |
| 152 | /** |
| 153 | * common_perm - basic common permission check wrapper fn for paths |
| 154 | * @op: operation being checked |
| 155 | * @path: path to check permission of (NOT NULL) |
| 156 | * @mask: requested permissions mask |
| 157 | * @cond: conditional info for the permission request (NOT NULL) |
| 158 | * |
| 159 | * Returns: %0 else error code if error or permission denied |
| 160 | */ |
| 161 | static int common_perm(int op, struct path *path, u32 mask, |
| 162 | struct path_cond *cond) |
| 163 | { |
| 164 | struct aa_profile *profile; |
| 165 | int error = 0; |
| 166 | |
| 167 | profile = __aa_current_profile(); |
| 168 | if (!unconfined(profile)) |
| 169 | error = aa_path_perm(op, profile, path, 0, mask, cond); |
| 170 | |
| 171 | return error; |
| 172 | } |
| 173 | |
| 174 | /** |
| 175 | * common_perm_dir_dentry - common permission wrapper when path is dir, dentry |
| 176 | * @op: operation being checked |
| 177 | * @dir: directory of the dentry (NOT NULL) |
| 178 | * @dentry: dentry to check (NOT NULL) |
| 179 | * @mask: requested permissions mask |
| 180 | * @cond: conditional info for the permission request (NOT NULL) |
| 181 | * |
| 182 | * Returns: %0 else error code if error or permission denied |
| 183 | */ |
| 184 | static int common_perm_dir_dentry(int op, struct path *dir, |
| 185 | struct dentry *dentry, u32 mask, |
| 186 | struct path_cond *cond) |
| 187 | { |
| 188 | struct path path = { dir->mnt, dentry }; |
| 189 | |
| 190 | return common_perm(op, &path, mask, cond); |
| 191 | } |
| 192 | |
| 193 | /** |
| 194 | * common_perm_mnt_dentry - common permission wrapper when mnt, dentry |
| 195 | * @op: operation being checked |
| 196 | * @mnt: mount point of dentry (NOT NULL) |
| 197 | * @dentry: dentry to check (NOT NULL) |
| 198 | * @mask: requested permissions mask |
| 199 | * |
| 200 | * Returns: %0 else error code if error or permission denied |
| 201 | */ |
| 202 | static int common_perm_mnt_dentry(int op, struct vfsmount *mnt, |
| 203 | struct dentry *dentry, u32 mask) |
| 204 | { |
| 205 | struct path path = { mnt, dentry }; |
| 206 | struct path_cond cond = { dentry->d_inode->i_uid, |
| 207 | dentry->d_inode->i_mode |
| 208 | }; |
| 209 | |
| 210 | return common_perm(op, &path, mask, &cond); |
| 211 | } |
| 212 | |
| 213 | /** |
| 214 | * common_perm_rm - common permission wrapper for operations doing rm |
| 215 | * @op: operation being checked |
| 216 | * @dir: directory that the dentry is in (NOT NULL) |
| 217 | * @dentry: dentry being rm'd (NOT NULL) |
| 218 | * @mask: requested permission mask |
| 219 | * |
| 220 | * Returns: %0 else error code if error or permission denied |
| 221 | */ |
| 222 | static int common_perm_rm(int op, struct path *dir, |
| 223 | struct dentry *dentry, u32 mask) |
| 224 | { |
| 225 | struct inode *inode = dentry->d_inode; |
| 226 | struct path_cond cond = { }; |
| 227 | |
| 228 | if (!inode || !dir->mnt || !mediated_filesystem(inode)) |
| 229 | return 0; |
| 230 | |
| 231 | cond.uid = inode->i_uid; |
| 232 | cond.mode = inode->i_mode; |
| 233 | |
| 234 | return common_perm_dir_dentry(op, dir, dentry, mask, &cond); |
| 235 | } |
| 236 | |
| 237 | /** |
| 238 | * common_perm_create - common permission wrapper for operations doing create |
| 239 | * @op: operation being checked |
| 240 | * @dir: directory that dentry will be created in (NOT NULL) |
| 241 | * @dentry: dentry to create (NOT NULL) |
| 242 | * @mask: request permission mask |
| 243 | * @mode: created file mode |
| 244 | * |
| 245 | * Returns: %0 else error code if error or permission denied |
| 246 | */ |
| 247 | static int common_perm_create(int op, struct path *dir, struct dentry *dentry, |
| 248 | u32 mask, umode_t mode) |
| 249 | { |
| 250 | struct path_cond cond = { current_fsuid(), mode }; |
| 251 | |
| 252 | if (!dir->mnt || !mediated_filesystem(dir->dentry->d_inode)) |
| 253 | return 0; |
| 254 | |
| 255 | return common_perm_dir_dentry(op, dir, dentry, mask, &cond); |
| 256 | } |
| 257 | |
| 258 | static int apparmor_path_unlink(struct path *dir, struct dentry *dentry) |
| 259 | { |
| 260 | return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE); |
| 261 | } |
| 262 | |
| 263 | static int apparmor_path_mkdir(struct path *dir, struct dentry *dentry, |
| 264 | int mode) |
| 265 | { |
| 266 | return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE, |
| 267 | S_IFDIR); |
| 268 | } |
| 269 | |
| 270 | static int apparmor_path_rmdir(struct path *dir, struct dentry *dentry) |
| 271 | { |
| 272 | return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE); |
| 273 | } |
| 274 | |
| 275 | static int apparmor_path_mknod(struct path *dir, struct dentry *dentry, |
| 276 | int mode, unsigned int dev) |
| 277 | { |
| 278 | return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode); |
| 279 | } |
| 280 | |
James Morris | 4d6ec10 | 2010-07-30 09:02:04 +1000 | [diff] [blame] | 281 | static int apparmor_path_truncate(struct path *path) |
John Johansen | b5e95b4 | 2010-07-29 14:48:07 -0700 | [diff] [blame] | 282 | { |
| 283 | struct path_cond cond = { path->dentry->d_inode->i_uid, |
| 284 | path->dentry->d_inode->i_mode |
| 285 | }; |
| 286 | |
| 287 | if (!path->mnt || !mediated_filesystem(path->dentry->d_inode)) |
| 288 | return 0; |
| 289 | |
| 290 | return common_perm(OP_TRUNC, path, MAY_WRITE | AA_MAY_META_WRITE, |
| 291 | &cond); |
| 292 | } |
| 293 | |
| 294 | static int apparmor_path_symlink(struct path *dir, struct dentry *dentry, |
| 295 | const char *old_name) |
| 296 | { |
| 297 | return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE, |
| 298 | S_IFLNK); |
| 299 | } |
| 300 | |
| 301 | static int apparmor_path_link(struct dentry *old_dentry, struct path *new_dir, |
| 302 | struct dentry *new_dentry) |
| 303 | { |
| 304 | struct aa_profile *profile; |
| 305 | int error = 0; |
| 306 | |
| 307 | if (!mediated_filesystem(old_dentry->d_inode)) |
| 308 | return 0; |
| 309 | |
| 310 | profile = aa_current_profile(); |
| 311 | if (!unconfined(profile)) |
| 312 | error = aa_path_link(profile, old_dentry, new_dir, new_dentry); |
| 313 | return error; |
| 314 | } |
| 315 | |
| 316 | static int apparmor_path_rename(struct path *old_dir, struct dentry *old_dentry, |
| 317 | struct path *new_dir, struct dentry *new_dentry) |
| 318 | { |
| 319 | struct aa_profile *profile; |
| 320 | int error = 0; |
| 321 | |
| 322 | if (!mediated_filesystem(old_dentry->d_inode)) |
| 323 | return 0; |
| 324 | |
| 325 | profile = aa_current_profile(); |
| 326 | if (!unconfined(profile)) { |
| 327 | struct path old_path = { old_dir->mnt, old_dentry }; |
| 328 | struct path new_path = { new_dir->mnt, new_dentry }; |
| 329 | struct path_cond cond = { old_dentry->d_inode->i_uid, |
| 330 | old_dentry->d_inode->i_mode |
| 331 | }; |
| 332 | |
| 333 | error = aa_path_perm(OP_RENAME_SRC, profile, &old_path, 0, |
| 334 | MAY_READ | AA_MAY_META_READ | MAY_WRITE | |
| 335 | AA_MAY_META_WRITE | AA_MAY_DELETE, |
| 336 | &cond); |
| 337 | if (!error) |
| 338 | error = aa_path_perm(OP_RENAME_DEST, profile, &new_path, |
| 339 | 0, MAY_WRITE | AA_MAY_META_WRITE | |
| 340 | AA_MAY_CREATE, &cond); |
| 341 | |
| 342 | } |
| 343 | return error; |
| 344 | } |
| 345 | |
| 346 | static int apparmor_path_chmod(struct dentry *dentry, struct vfsmount *mnt, |
| 347 | mode_t mode) |
| 348 | { |
| 349 | if (!mediated_filesystem(dentry->d_inode)) |
| 350 | return 0; |
| 351 | |
| 352 | return common_perm_mnt_dentry(OP_CHMOD, mnt, dentry, AA_MAY_CHMOD); |
| 353 | } |
| 354 | |
| 355 | static int apparmor_path_chown(struct path *path, uid_t uid, gid_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_dentry_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->f_path.dentry->d_inode)) |
| 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->f_path.dentry->d_inode; |
| 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->f_path.dentry->d_inode)) |
| 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 | struct dentry *dentry; |
| 473 | int mask = 0; |
| 474 | |
| 475 | if (!file || !file->f_security) |
| 476 | return 0; |
| 477 | |
| 478 | if (prot & PROT_READ) |
| 479 | mask |= MAY_READ; |
| 480 | /* |
| 481 | * Private mappings don't require write perms since they don't |
| 482 | * write back to the files |
| 483 | */ |
| 484 | if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE)) |
| 485 | mask |= MAY_WRITE; |
| 486 | if (prot & PROT_EXEC) |
| 487 | mask |= AA_EXEC_MMAP; |
| 488 | |
| 489 | dentry = file->f_path.dentry; |
| 490 | return common_file_perm(op, file, mask); |
| 491 | } |
| 492 | |
| 493 | static int apparmor_file_mmap(struct file *file, unsigned long reqprot, |
| 494 | unsigned long prot, unsigned long flags, |
| 495 | unsigned long addr, unsigned long addr_only) |
| 496 | { |
| 497 | int rc = 0; |
| 498 | |
| 499 | /* do DAC check */ |
| 500 | rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only); |
| 501 | if (rc || addr_only) |
| 502 | return rc; |
| 503 | |
| 504 | return common_mmap(OP_FMMAP, file, prot, flags); |
| 505 | } |
| 506 | |
| 507 | static int apparmor_file_mprotect(struct vm_area_struct *vma, |
| 508 | unsigned long reqprot, unsigned long prot) |
| 509 | { |
| 510 | return common_mmap(OP_FMPROT, vma->vm_file, prot, |
| 511 | !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0); |
| 512 | } |
| 513 | |
| 514 | static int apparmor_getprocattr(struct task_struct *task, char *name, |
| 515 | char **value) |
| 516 | { |
| 517 | int error = -ENOENT; |
| 518 | struct aa_profile *profile; |
| 519 | /* released below */ |
| 520 | const struct cred *cred = get_task_cred(task); |
| 521 | struct aa_task_cxt *cxt = cred->security; |
| 522 | profile = aa_cred_profile(cred); |
| 523 | |
| 524 | if (strcmp(name, "current") == 0) |
| 525 | error = aa_getprocattr(aa_newest_version(cxt->profile), |
| 526 | value); |
| 527 | else if (strcmp(name, "prev") == 0 && cxt->previous) |
| 528 | error = aa_getprocattr(aa_newest_version(cxt->previous), |
| 529 | value); |
| 530 | else if (strcmp(name, "exec") == 0 && cxt->onexec) |
| 531 | error = aa_getprocattr(aa_newest_version(cxt->onexec), |
| 532 | value); |
| 533 | else |
| 534 | error = -EINVAL; |
| 535 | |
| 536 | put_cred(cred); |
| 537 | |
| 538 | return error; |
| 539 | } |
| 540 | |
| 541 | static int apparmor_setprocattr(struct task_struct *task, char *name, |
| 542 | void *value, size_t size) |
| 543 | { |
| 544 | char *command, *args = value; |
| 545 | size_t arg_size; |
| 546 | int error; |
| 547 | |
| 548 | if (size == 0) |
| 549 | return -EINVAL; |
| 550 | /* args points to a PAGE_SIZE buffer, AppArmor requires that |
| 551 | * the buffer must be null terminated or have size <= PAGE_SIZE -1 |
| 552 | * so that AppArmor can null terminate them |
| 553 | */ |
| 554 | if (args[size - 1] != '\0') { |
| 555 | if (size == PAGE_SIZE) |
| 556 | return -EINVAL; |
| 557 | args[size] = '\0'; |
| 558 | } |
| 559 | |
| 560 | /* task can only write its own attributes */ |
| 561 | if (current != task) |
| 562 | return -EACCES; |
| 563 | |
| 564 | args = value; |
| 565 | args = strim(args); |
| 566 | command = strsep(&args, " "); |
| 567 | if (!args) |
| 568 | return -EINVAL; |
| 569 | args = skip_spaces(args); |
| 570 | if (!*args) |
| 571 | return -EINVAL; |
| 572 | |
| 573 | arg_size = size - (args - (char *) value); |
| 574 | if (strcmp(name, "current") == 0) { |
| 575 | if (strcmp(command, "changehat") == 0) { |
| 576 | error = aa_setprocattr_changehat(args, arg_size, |
| 577 | !AA_DO_TEST); |
| 578 | } else if (strcmp(command, "permhat") == 0) { |
| 579 | error = aa_setprocattr_changehat(args, arg_size, |
| 580 | AA_DO_TEST); |
| 581 | } else if (strcmp(command, "changeprofile") == 0) { |
| 582 | error = aa_setprocattr_changeprofile(args, !AA_ONEXEC, |
| 583 | !AA_DO_TEST); |
| 584 | } else if (strcmp(command, "permprofile") == 0) { |
| 585 | error = aa_setprocattr_changeprofile(args, !AA_ONEXEC, |
| 586 | AA_DO_TEST); |
| 587 | } else if (strcmp(command, "permipc") == 0) { |
| 588 | error = aa_setprocattr_permipc(args); |
| 589 | } else { |
| 590 | struct common_audit_data sa; |
| 591 | COMMON_AUDIT_DATA_INIT(&sa, NONE); |
| 592 | sa.aad.op = OP_SETPROCATTR; |
| 593 | sa.aad.info = name; |
| 594 | sa.aad.error = -EINVAL; |
| 595 | return aa_audit(AUDIT_APPARMOR_DENIED, NULL, GFP_KERNEL, |
| 596 | &sa, NULL); |
| 597 | } |
| 598 | } else if (strcmp(name, "exec") == 0) { |
| 599 | error = aa_setprocattr_changeprofile(args, AA_ONEXEC, |
| 600 | !AA_DO_TEST); |
| 601 | } else { |
| 602 | /* only support the "current" and "exec" process attributes */ |
| 603 | return -EINVAL; |
| 604 | } |
| 605 | if (!error) |
| 606 | error = size; |
| 607 | return error; |
| 608 | } |
| 609 | |
Jiri Slaby | 7cb4dc9 | 2010-08-11 11:28:02 +0200 | [diff] [blame] | 610 | static int apparmor_task_setrlimit(struct task_struct *task, |
| 611 | unsigned int resource, struct rlimit *new_rlim) |
John Johansen | b5e95b4 | 2010-07-29 14:48:07 -0700 | [diff] [blame] | 612 | { |
| 613 | struct aa_profile *profile = aa_current_profile(); |
| 614 | int error = 0; |
| 615 | |
| 616 | if (!unconfined(profile)) |
| 617 | error = aa_task_setrlimit(profile, resource, new_rlim); |
| 618 | |
| 619 | return error; |
| 620 | } |
| 621 | |
| 622 | static struct security_operations apparmor_ops = { |
| 623 | .name = "apparmor", |
| 624 | |
| 625 | .ptrace_access_check = apparmor_ptrace_access_check, |
| 626 | .ptrace_traceme = apparmor_ptrace_traceme, |
| 627 | .capget = apparmor_capget, |
| 628 | .capable = apparmor_capable, |
| 629 | |
| 630 | .path_link = apparmor_path_link, |
| 631 | .path_unlink = apparmor_path_unlink, |
| 632 | .path_symlink = apparmor_path_symlink, |
| 633 | .path_mkdir = apparmor_path_mkdir, |
| 634 | .path_rmdir = apparmor_path_rmdir, |
| 635 | .path_mknod = apparmor_path_mknod, |
| 636 | .path_rename = apparmor_path_rename, |
| 637 | .path_chmod = apparmor_path_chmod, |
| 638 | .path_chown = apparmor_path_chown, |
| 639 | .path_truncate = apparmor_path_truncate, |
| 640 | .dentry_open = apparmor_dentry_open, |
| 641 | .inode_getattr = apparmor_inode_getattr, |
| 642 | |
| 643 | .file_permission = apparmor_file_permission, |
| 644 | .file_alloc_security = apparmor_file_alloc_security, |
| 645 | .file_free_security = apparmor_file_free_security, |
| 646 | .file_mmap = apparmor_file_mmap, |
| 647 | .file_mprotect = apparmor_file_mprotect, |
| 648 | .file_lock = apparmor_file_lock, |
| 649 | |
| 650 | .getprocattr = apparmor_getprocattr, |
| 651 | .setprocattr = apparmor_setprocattr, |
| 652 | |
| 653 | .cred_alloc_blank = apparmor_cred_alloc_blank, |
| 654 | .cred_free = apparmor_cred_free, |
| 655 | .cred_prepare = apparmor_cred_prepare, |
| 656 | .cred_transfer = apparmor_cred_transfer, |
| 657 | |
| 658 | .bprm_set_creds = apparmor_bprm_set_creds, |
| 659 | .bprm_committing_creds = apparmor_bprm_committing_creds, |
| 660 | .bprm_committed_creds = apparmor_bprm_committed_creds, |
| 661 | .bprm_secureexec = apparmor_bprm_secureexec, |
| 662 | |
| 663 | .task_setrlimit = apparmor_task_setrlimit, |
| 664 | }; |
| 665 | |
| 666 | /* |
| 667 | * AppArmor sysfs module parameters |
| 668 | */ |
| 669 | |
Stephen Rothwell | 101d6c8 | 2010-08-02 12:00:43 +1000 | [diff] [blame] | 670 | static int param_set_aabool(const char *val, const struct kernel_param *kp); |
| 671 | static int param_get_aabool(char *buffer, const struct kernel_param *kp); |
John Johansen | b5e95b4 | 2010-07-29 14:48:07 -0700 | [diff] [blame] | 672 | #define param_check_aabool(name, p) __param_check(name, p, int) |
Stephen Rothwell | 101d6c8 | 2010-08-02 12:00:43 +1000 | [diff] [blame] | 673 | static struct kernel_param_ops param_ops_aabool = { |
| 674 | .set = param_set_aabool, |
| 675 | .get = param_get_aabool |
| 676 | }; |
John Johansen | b5e95b4 | 2010-07-29 14:48:07 -0700 | [diff] [blame] | 677 | |
Stephen Rothwell | 101d6c8 | 2010-08-02 12:00:43 +1000 | [diff] [blame] | 678 | static int param_set_aauint(const char *val, const struct kernel_param *kp); |
| 679 | static int param_get_aauint(char *buffer, const struct kernel_param *kp); |
John Johansen | b5e95b4 | 2010-07-29 14:48:07 -0700 | [diff] [blame] | 680 | #define param_check_aauint(name, p) __param_check(name, p, int) |
Stephen Rothwell | 101d6c8 | 2010-08-02 12:00:43 +1000 | [diff] [blame] | 681 | static struct kernel_param_ops param_ops_aauint = { |
| 682 | .set = param_set_aauint, |
| 683 | .get = param_get_aauint |
| 684 | }; |
John Johansen | b5e95b4 | 2010-07-29 14:48:07 -0700 | [diff] [blame] | 685 | |
Stephen Rothwell | 101d6c8 | 2010-08-02 12:00:43 +1000 | [diff] [blame] | 686 | static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp); |
| 687 | static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp); |
John Johansen | b5e95b4 | 2010-07-29 14:48:07 -0700 | [diff] [blame] | 688 | #define param_check_aalockpolicy(name, p) __param_check(name, p, int) |
Stephen Rothwell | 101d6c8 | 2010-08-02 12:00:43 +1000 | [diff] [blame] | 689 | static struct kernel_param_ops param_ops_aalockpolicy = { |
| 690 | .set = param_set_aalockpolicy, |
| 691 | .get = param_get_aalockpolicy |
| 692 | }; |
John Johansen | b5e95b4 | 2010-07-29 14:48:07 -0700 | [diff] [blame] | 693 | |
| 694 | static int param_set_audit(const char *val, struct kernel_param *kp); |
| 695 | static int param_get_audit(char *buffer, struct kernel_param *kp); |
| 696 | #define param_check_audit(name, p) __param_check(name, p, int) |
| 697 | |
| 698 | static int param_set_mode(const char *val, struct kernel_param *kp); |
| 699 | static int param_get_mode(char *buffer, struct kernel_param *kp); |
| 700 | #define param_check_mode(name, p) __param_check(name, p, int) |
| 701 | |
| 702 | /* Flag values, also controllable via /sys/module/apparmor/parameters |
| 703 | * We define special types as we want to do additional mediation. |
| 704 | */ |
| 705 | |
| 706 | /* AppArmor global enforcement switch - complain, enforce, kill */ |
| 707 | enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE; |
| 708 | module_param_call(mode, param_set_mode, param_get_mode, |
| 709 | &aa_g_profile_mode, S_IRUSR | S_IWUSR); |
| 710 | |
| 711 | /* Debug mode */ |
| 712 | int aa_g_debug; |
| 713 | module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR); |
| 714 | |
| 715 | /* Audit mode */ |
| 716 | enum audit_mode aa_g_audit; |
| 717 | module_param_call(audit, param_set_audit, param_get_audit, |
| 718 | &aa_g_audit, S_IRUSR | S_IWUSR); |
| 719 | |
| 720 | /* Determines if audit header is included in audited messages. This |
| 721 | * provides more context if the audit daemon is not running |
| 722 | */ |
| 723 | int aa_g_audit_header = 1; |
| 724 | module_param_named(audit_header, aa_g_audit_header, aabool, |
| 725 | S_IRUSR | S_IWUSR); |
| 726 | |
| 727 | /* lock out loading/removal of policy |
| 728 | * TODO: add in at boot loading of policy, which is the only way to |
| 729 | * load policy, if lock_policy is set |
| 730 | */ |
| 731 | int aa_g_lock_policy; |
| 732 | module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy, |
| 733 | S_IRUSR | S_IWUSR); |
| 734 | |
| 735 | /* Syscall logging mode */ |
| 736 | int aa_g_logsyscall; |
| 737 | module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR); |
| 738 | |
| 739 | /* Maximum pathname length before accesses will start getting rejected */ |
| 740 | unsigned int aa_g_path_max = 2 * PATH_MAX; |
| 741 | module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR | S_IWUSR); |
| 742 | |
| 743 | /* Determines how paranoid loading of policy is and how much verification |
| 744 | * on the loaded policy is done. |
| 745 | */ |
| 746 | int aa_g_paranoid_load = 1; |
| 747 | module_param_named(paranoid_load, aa_g_paranoid_load, aabool, |
| 748 | S_IRUSR | S_IWUSR); |
| 749 | |
| 750 | /* Boot time disable flag */ |
| 751 | static unsigned int apparmor_enabled = CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE; |
| 752 | module_param_named(enabled, apparmor_enabled, aabool, S_IRUSR); |
| 753 | |
| 754 | static int __init apparmor_enabled_setup(char *str) |
| 755 | { |
| 756 | unsigned long enabled; |
| 757 | int error = strict_strtoul(str, 0, &enabled); |
| 758 | if (!error) |
| 759 | apparmor_enabled = enabled ? 1 : 0; |
| 760 | return 1; |
| 761 | } |
| 762 | |
| 763 | __setup("apparmor=", apparmor_enabled_setup); |
| 764 | |
| 765 | /* set global flag turning off the ability to load policy */ |
Stephen Rothwell | 101d6c8 | 2010-08-02 12:00:43 +1000 | [diff] [blame] | 766 | static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp) |
John Johansen | b5e95b4 | 2010-07-29 14:48:07 -0700 | [diff] [blame] | 767 | { |
| 768 | if (!capable(CAP_MAC_ADMIN)) |
| 769 | return -EPERM; |
| 770 | if (aa_g_lock_policy) |
| 771 | return -EACCES; |
| 772 | return param_set_bool(val, kp); |
| 773 | } |
| 774 | |
Stephen Rothwell | 101d6c8 | 2010-08-02 12:00:43 +1000 | [diff] [blame] | 775 | static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp) |
John Johansen | b5e95b4 | 2010-07-29 14:48:07 -0700 | [diff] [blame] | 776 | { |
| 777 | if (!capable(CAP_MAC_ADMIN)) |
| 778 | return -EPERM; |
| 779 | return param_get_bool(buffer, kp); |
| 780 | } |
| 781 | |
Stephen Rothwell | 101d6c8 | 2010-08-02 12:00:43 +1000 | [diff] [blame] | 782 | static int param_set_aabool(const char *val, const struct kernel_param *kp) |
John Johansen | b5e95b4 | 2010-07-29 14:48:07 -0700 | [diff] [blame] | 783 | { |
| 784 | if (!capable(CAP_MAC_ADMIN)) |
| 785 | return -EPERM; |
| 786 | return param_set_bool(val, kp); |
| 787 | } |
| 788 | |
Stephen Rothwell | 101d6c8 | 2010-08-02 12:00:43 +1000 | [diff] [blame] | 789 | static int param_get_aabool(char *buffer, const struct kernel_param *kp) |
John Johansen | b5e95b4 | 2010-07-29 14:48:07 -0700 | [diff] [blame] | 790 | { |
| 791 | if (!capable(CAP_MAC_ADMIN)) |
| 792 | return -EPERM; |
| 793 | return param_get_bool(buffer, kp); |
| 794 | } |
| 795 | |
Stephen Rothwell | 101d6c8 | 2010-08-02 12:00:43 +1000 | [diff] [blame] | 796 | static int param_set_aauint(const char *val, const struct kernel_param *kp) |
John Johansen | b5e95b4 | 2010-07-29 14:48:07 -0700 | [diff] [blame] | 797 | { |
| 798 | if (!capable(CAP_MAC_ADMIN)) |
| 799 | return -EPERM; |
| 800 | return param_set_uint(val, kp); |
| 801 | } |
| 802 | |
Stephen Rothwell | 101d6c8 | 2010-08-02 12:00:43 +1000 | [diff] [blame] | 803 | static int param_get_aauint(char *buffer, const struct kernel_param *kp) |
John Johansen | b5e95b4 | 2010-07-29 14:48:07 -0700 | [diff] [blame] | 804 | { |
| 805 | if (!capable(CAP_MAC_ADMIN)) |
| 806 | return -EPERM; |
| 807 | return param_get_uint(buffer, kp); |
| 808 | } |
| 809 | |
| 810 | static int param_get_audit(char *buffer, struct kernel_param *kp) |
| 811 | { |
| 812 | if (!capable(CAP_MAC_ADMIN)) |
| 813 | return -EPERM; |
| 814 | |
| 815 | if (!apparmor_enabled) |
| 816 | return -EINVAL; |
| 817 | |
| 818 | return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]); |
| 819 | } |
| 820 | |
| 821 | static int param_set_audit(const char *val, struct kernel_param *kp) |
| 822 | { |
| 823 | int i; |
| 824 | if (!capable(CAP_MAC_ADMIN)) |
| 825 | return -EPERM; |
| 826 | |
| 827 | if (!apparmor_enabled) |
| 828 | return -EINVAL; |
| 829 | |
| 830 | if (!val) |
| 831 | return -EINVAL; |
| 832 | |
| 833 | for (i = 0; i < AUDIT_MAX_INDEX; i++) { |
| 834 | if (strcmp(val, audit_mode_names[i]) == 0) { |
| 835 | aa_g_audit = i; |
| 836 | return 0; |
| 837 | } |
| 838 | } |
| 839 | |
| 840 | return -EINVAL; |
| 841 | } |
| 842 | |
| 843 | static int param_get_mode(char *buffer, struct kernel_param *kp) |
| 844 | { |
| 845 | if (!capable(CAP_MAC_ADMIN)) |
| 846 | return -EPERM; |
| 847 | |
| 848 | if (!apparmor_enabled) |
| 849 | return -EINVAL; |
| 850 | |
| 851 | return sprintf(buffer, "%s", profile_mode_names[aa_g_profile_mode]); |
| 852 | } |
| 853 | |
| 854 | static int param_set_mode(const char *val, struct kernel_param *kp) |
| 855 | { |
| 856 | int i; |
| 857 | if (!capable(CAP_MAC_ADMIN)) |
| 858 | return -EPERM; |
| 859 | |
| 860 | if (!apparmor_enabled) |
| 861 | return -EINVAL; |
| 862 | |
| 863 | if (!val) |
| 864 | return -EINVAL; |
| 865 | |
| 866 | for (i = 0; i < APPARMOR_NAMES_MAX_INDEX; i++) { |
| 867 | if (strcmp(val, profile_mode_names[i]) == 0) { |
| 868 | aa_g_profile_mode = i; |
| 869 | return 0; |
| 870 | } |
| 871 | } |
| 872 | |
| 873 | return -EINVAL; |
| 874 | } |
| 875 | |
| 876 | /* |
| 877 | * AppArmor init functions |
| 878 | */ |
| 879 | |
| 880 | /** |
| 881 | * set_init_cxt - set a task context and profile on the first task. |
| 882 | * |
| 883 | * TODO: allow setting an alternate profile than unconfined |
| 884 | */ |
| 885 | static int __init set_init_cxt(void) |
| 886 | { |
| 887 | struct cred *cred = (struct cred *)current->real_cred; |
| 888 | struct aa_task_cxt *cxt; |
| 889 | |
| 890 | cxt = aa_alloc_task_context(GFP_KERNEL); |
| 891 | if (!cxt) |
| 892 | return -ENOMEM; |
| 893 | |
| 894 | cxt->profile = aa_get_profile(root_ns->unconfined); |
| 895 | cred->security = cxt; |
| 896 | |
| 897 | return 0; |
| 898 | } |
| 899 | |
| 900 | static int __init apparmor_init(void) |
| 901 | { |
| 902 | int error; |
| 903 | |
| 904 | if (!apparmor_enabled || !security_module_enable(&apparmor_ops)) { |
| 905 | aa_info_message("AppArmor disabled by boot time parameter"); |
| 906 | apparmor_enabled = 0; |
| 907 | return 0; |
| 908 | } |
| 909 | |
| 910 | error = aa_alloc_root_ns(); |
| 911 | if (error) { |
| 912 | AA_ERROR("Unable to allocate default profile namespace\n"); |
| 913 | goto alloc_out; |
| 914 | } |
| 915 | |
| 916 | error = set_init_cxt(); |
| 917 | if (error) { |
| 918 | AA_ERROR("Failed to set context on init task\n"); |
| 919 | goto register_security_out; |
| 920 | } |
| 921 | |
| 922 | error = register_security(&apparmor_ops); |
| 923 | if (error) { |
| 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 | |
| 950 | security_initcall(apparmor_init); |