1 /* Updated: Karl MacMillan <kmacmillan@tresys.com> 2 * 3 * Added conditional policy language extensions 4 * 5 * Updated: Hewlett-Packard <paul@paul-moore.com> 6 * 7 * Added support for the policy capability bitmap 8 * 9 * Copyright (C) 2007 Hewlett-Packard Development Company, L.P. 10 * Copyright (C) 2003 - 2004 Tresys Technology, LLC 11 * Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com> 12 * This program is free software; you can redistribute it and/or modify 13 * it under the terms of the GNU General Public License as published by 14 * the Free Software Foundation, version 2. 15 */ 16 17 #include <linux/kernel.h> 18 #include <linux/pagemap.h> 19 #include <linux/slab.h> 20 #include <linux/vmalloc.h> 21 #include <linux/fs.h> 22 #include <linux/mutex.h> 23 #include <linux/init.h> 24 #include <linux/string.h> 25 #include <linux/security.h> 26 #include <linux/major.h> 27 #include <linux/seq_file.h> 28 #include <linux/percpu.h> 29 #include <linux/audit.h> 30 #include <linux/uaccess.h> 31 #include <linux/kobject.h> 32 #include <linux/ctype.h> 33 34 /* selinuxfs pseudo filesystem for exporting the security policy API. 35 Based on the proc code and the fs/nfsd/nfsctl.c code. */ 36 37 #include "flask.h" 38 #include "avc.h" 39 #include "avc_ss.h" 40 #include "security.h" 41 #include "objsec.h" 42 #include "conditional.h" 43 44 /* Policy capability filenames */ 45 static char *policycap_names[] = { 46 "network_peer_controls", 47 "open_perms", 48 "redhat1", 49 "always_check_network" 50 }; 51 52 unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE; 53 54 static int __init checkreqprot_setup(char *str) 55 { 56 unsigned long checkreqprot; 57 if (!kstrtoul(str, 0, &checkreqprot)) 58 selinux_checkreqprot = checkreqprot ? 1 : 0; 59 return 1; 60 } 61 __setup("checkreqprot=", checkreqprot_setup); 62 63 static DEFINE_MUTEX(sel_mutex); 64 65 /* global data for booleans */ 66 static struct dentry *bool_dir; 67 static int bool_num; 68 static char **bool_pending_names; 69 static int *bool_pending_values; 70 71 /* global data for classes */ 72 static struct dentry *class_dir; 73 static unsigned long last_class_ino; 74 75 static char policy_opened; 76 77 /* global data for policy capabilities */ 78 static struct dentry *policycap_dir; 79 80 /* Check whether a task is allowed to use a security operation. */ 81 static int task_has_security(struct task_struct *tsk, 82 u32 perms) 83 { 84 const struct task_security_struct *tsec; 85 u32 sid = 0; 86 87 rcu_read_lock(); 88 tsec = __task_cred(tsk)->security; 89 if (tsec) 90 sid = tsec->sid; 91 rcu_read_unlock(); 92 if (!tsec) 93 return -EACCES; 94 95 return avc_has_perm(sid, SECINITSID_SECURITY, 96 SECCLASS_SECURITY, perms, NULL); 97 } 98 99 enum sel_inos { 100 SEL_ROOT_INO = 2, 101 SEL_LOAD, /* load policy */ 102 SEL_ENFORCE, /* get or set enforcing status */ 103 SEL_CONTEXT, /* validate context */ 104 SEL_ACCESS, /* compute access decision */ 105 SEL_CREATE, /* compute create labeling decision */ 106 SEL_RELABEL, /* compute relabeling decision */ 107 SEL_USER, /* compute reachable user contexts */ 108 SEL_POLICYVERS, /* return policy version for this kernel */ 109 SEL_COMMIT_BOOLS, /* commit new boolean values */ 110 SEL_MLS, /* return if MLS policy is enabled */ 111 SEL_DISABLE, /* disable SELinux until next reboot */ 112 SEL_MEMBER, /* compute polyinstantiation membership decision */ 113 SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */ 114 SEL_COMPAT_NET, /* whether to use old compat network packet controls */ 115 SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */ 116 SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */ 117 SEL_STATUS, /* export current status using mmap() */ 118 SEL_POLICY, /* allow userspace to read the in kernel policy */ 119 SEL_VALIDATE_TRANS, /* compute validatetrans decision */ 120 SEL_INO_NEXT, /* The next inode number to use */ 121 }; 122 123 static unsigned long sel_last_ino = SEL_INO_NEXT - 1; 124 125 #define SEL_INITCON_INO_OFFSET 0x01000000 126 #define SEL_BOOL_INO_OFFSET 0x02000000 127 #define SEL_CLASS_INO_OFFSET 0x04000000 128 #define SEL_POLICYCAP_INO_OFFSET 0x08000000 129 #define SEL_INO_MASK 0x00ffffff 130 131 #define TMPBUFLEN 12 132 static ssize_t sel_read_enforce(struct file *filp, char __user *buf, 133 size_t count, loff_t *ppos) 134 { 135 char tmpbuf[TMPBUFLEN]; 136 ssize_t length; 137 138 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing); 139 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 140 } 141 142 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 143 static ssize_t sel_write_enforce(struct file *file, const char __user *buf, 144 size_t count, loff_t *ppos) 145 146 { 147 char *page = NULL; 148 ssize_t length; 149 int new_value; 150 151 if (count >= PAGE_SIZE) 152 return -ENOMEM; 153 154 /* No partial writes. */ 155 if (*ppos != 0) 156 return -EINVAL; 157 158 page = memdup_user_nul(buf, count); 159 if (IS_ERR(page)) 160 return PTR_ERR(page); 161 162 length = -EINVAL; 163 if (sscanf(page, "%d", &new_value) != 1) 164 goto out; 165 166 new_value = !!new_value; 167 168 if (new_value != selinux_enforcing) { 169 length = task_has_security(current, SECURITY__SETENFORCE); 170 if (length) 171 goto out; 172 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS, 173 "enforcing=%d old_enforcing=%d auid=%u ses=%u", 174 new_value, selinux_enforcing, 175 from_kuid(&init_user_ns, audit_get_loginuid(current)), 176 audit_get_sessionid(current)); 177 selinux_enforcing = new_value; 178 if (selinux_enforcing) 179 avc_ss_reset(0); 180 selnl_notify_setenforce(selinux_enforcing); 181 selinux_status_update_setenforce(selinux_enforcing); 182 } 183 length = count; 184 out: 185 kfree(page); 186 return length; 187 } 188 #else 189 #define sel_write_enforce NULL 190 #endif 191 192 static const struct file_operations sel_enforce_ops = { 193 .read = sel_read_enforce, 194 .write = sel_write_enforce, 195 .llseek = generic_file_llseek, 196 }; 197 198 static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf, 199 size_t count, loff_t *ppos) 200 { 201 char tmpbuf[TMPBUFLEN]; 202 ssize_t length; 203 ino_t ino = file_inode(filp)->i_ino; 204 int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ? 205 security_get_reject_unknown() : !security_get_allow_unknown(); 206 207 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown); 208 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 209 } 210 211 static const struct file_operations sel_handle_unknown_ops = { 212 .read = sel_read_handle_unknown, 213 .llseek = generic_file_llseek, 214 }; 215 216 static int sel_open_handle_status(struct inode *inode, struct file *filp) 217 { 218 struct page *status = selinux_kernel_status_page(); 219 220 if (!status) 221 return -ENOMEM; 222 223 filp->private_data = status; 224 225 return 0; 226 } 227 228 static ssize_t sel_read_handle_status(struct file *filp, char __user *buf, 229 size_t count, loff_t *ppos) 230 { 231 struct page *status = filp->private_data; 232 233 BUG_ON(!status); 234 235 return simple_read_from_buffer(buf, count, ppos, 236 page_address(status), 237 sizeof(struct selinux_kernel_status)); 238 } 239 240 static int sel_mmap_handle_status(struct file *filp, 241 struct vm_area_struct *vma) 242 { 243 struct page *status = filp->private_data; 244 unsigned long size = vma->vm_end - vma->vm_start; 245 246 BUG_ON(!status); 247 248 /* only allows one page from the head */ 249 if (vma->vm_pgoff > 0 || size != PAGE_SIZE) 250 return -EIO; 251 /* disallow writable mapping */ 252 if (vma->vm_flags & VM_WRITE) 253 return -EPERM; 254 /* disallow mprotect() turns it into writable */ 255 vma->vm_flags &= ~VM_MAYWRITE; 256 257 return remap_pfn_range(vma, vma->vm_start, 258 page_to_pfn(status), 259 size, vma->vm_page_prot); 260 } 261 262 static const struct file_operations sel_handle_status_ops = { 263 .open = sel_open_handle_status, 264 .read = sel_read_handle_status, 265 .mmap = sel_mmap_handle_status, 266 .llseek = generic_file_llseek, 267 }; 268 269 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 270 static ssize_t sel_write_disable(struct file *file, const char __user *buf, 271 size_t count, loff_t *ppos) 272 273 { 274 char *page; 275 ssize_t length; 276 int new_value; 277 278 if (count >= PAGE_SIZE) 279 return -ENOMEM; 280 281 /* No partial writes. */ 282 if (*ppos != 0) 283 return -EINVAL; 284 285 page = memdup_user_nul(buf, count); 286 if (IS_ERR(page)) 287 return PTR_ERR(page); 288 289 length = -EINVAL; 290 if (sscanf(page, "%d", &new_value) != 1) 291 goto out; 292 293 if (new_value) { 294 length = selinux_disable(); 295 if (length) 296 goto out; 297 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS, 298 "selinux=0 auid=%u ses=%u", 299 from_kuid(&init_user_ns, audit_get_loginuid(current)), 300 audit_get_sessionid(current)); 301 } 302 303 length = count; 304 out: 305 kfree(page); 306 return length; 307 } 308 #else 309 #define sel_write_disable NULL 310 #endif 311 312 static const struct file_operations sel_disable_ops = { 313 .write = sel_write_disable, 314 .llseek = generic_file_llseek, 315 }; 316 317 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf, 318 size_t count, loff_t *ppos) 319 { 320 char tmpbuf[TMPBUFLEN]; 321 ssize_t length; 322 323 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX); 324 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 325 } 326 327 static const struct file_operations sel_policyvers_ops = { 328 .read = sel_read_policyvers, 329 .llseek = generic_file_llseek, 330 }; 331 332 /* declaration for sel_write_load */ 333 static int sel_make_bools(void); 334 static int sel_make_classes(void); 335 static int sel_make_policycap(void); 336 337 /* declaration for sel_make_class_dirs */ 338 static struct dentry *sel_make_dir(struct dentry *dir, const char *name, 339 unsigned long *ino); 340 341 static ssize_t sel_read_mls(struct file *filp, char __user *buf, 342 size_t count, loff_t *ppos) 343 { 344 char tmpbuf[TMPBUFLEN]; 345 ssize_t length; 346 347 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", 348 security_mls_enabled()); 349 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 350 } 351 352 static const struct file_operations sel_mls_ops = { 353 .read = sel_read_mls, 354 .llseek = generic_file_llseek, 355 }; 356 357 struct policy_load_memory { 358 size_t len; 359 void *data; 360 }; 361 362 static int sel_open_policy(struct inode *inode, struct file *filp) 363 { 364 struct policy_load_memory *plm = NULL; 365 int rc; 366 367 BUG_ON(filp->private_data); 368 369 mutex_lock(&sel_mutex); 370 371 rc = task_has_security(current, SECURITY__READ_POLICY); 372 if (rc) 373 goto err; 374 375 rc = -EBUSY; 376 if (policy_opened) 377 goto err; 378 379 rc = -ENOMEM; 380 plm = kzalloc(sizeof(*plm), GFP_KERNEL); 381 if (!plm) 382 goto err; 383 384 if (i_size_read(inode) != security_policydb_len()) { 385 inode_lock(inode); 386 i_size_write(inode, security_policydb_len()); 387 inode_unlock(inode); 388 } 389 390 rc = security_read_policy(&plm->data, &plm->len); 391 if (rc) 392 goto err; 393 394 policy_opened = 1; 395 396 filp->private_data = plm; 397 398 mutex_unlock(&sel_mutex); 399 400 return 0; 401 err: 402 mutex_unlock(&sel_mutex); 403 404 if (plm) 405 vfree(plm->data); 406 kfree(plm); 407 return rc; 408 } 409 410 static int sel_release_policy(struct inode *inode, struct file *filp) 411 { 412 struct policy_load_memory *plm = filp->private_data; 413 414 BUG_ON(!plm); 415 416 policy_opened = 0; 417 418 vfree(plm->data); 419 kfree(plm); 420 421 return 0; 422 } 423 424 static ssize_t sel_read_policy(struct file *filp, char __user *buf, 425 size_t count, loff_t *ppos) 426 { 427 struct policy_load_memory *plm = filp->private_data; 428 int ret; 429 430 mutex_lock(&sel_mutex); 431 432 ret = task_has_security(current, SECURITY__READ_POLICY); 433 if (ret) 434 goto out; 435 436 ret = simple_read_from_buffer(buf, count, ppos, plm->data, plm->len); 437 out: 438 mutex_unlock(&sel_mutex); 439 return ret; 440 } 441 442 static int sel_mmap_policy_fault(struct vm_area_struct *vma, 443 struct vm_fault *vmf) 444 { 445 struct policy_load_memory *plm = vma->vm_file->private_data; 446 unsigned long offset; 447 struct page *page; 448 449 if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE)) 450 return VM_FAULT_SIGBUS; 451 452 offset = vmf->pgoff << PAGE_SHIFT; 453 if (offset >= roundup(plm->len, PAGE_SIZE)) 454 return VM_FAULT_SIGBUS; 455 456 page = vmalloc_to_page(plm->data + offset); 457 get_page(page); 458 459 vmf->page = page; 460 461 return 0; 462 } 463 464 static const struct vm_operations_struct sel_mmap_policy_ops = { 465 .fault = sel_mmap_policy_fault, 466 .page_mkwrite = sel_mmap_policy_fault, 467 }; 468 469 static int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma) 470 { 471 if (vma->vm_flags & VM_SHARED) { 472 /* do not allow mprotect to make mapping writable */ 473 vma->vm_flags &= ~VM_MAYWRITE; 474 475 if (vma->vm_flags & VM_WRITE) 476 return -EACCES; 477 } 478 479 vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP; 480 vma->vm_ops = &sel_mmap_policy_ops; 481 482 return 0; 483 } 484 485 static const struct file_operations sel_policy_ops = { 486 .open = sel_open_policy, 487 .read = sel_read_policy, 488 .mmap = sel_mmap_policy, 489 .release = sel_release_policy, 490 .llseek = generic_file_llseek, 491 }; 492 493 static ssize_t sel_write_load(struct file *file, const char __user *buf, 494 size_t count, loff_t *ppos) 495 496 { 497 ssize_t length; 498 void *data = NULL; 499 500 mutex_lock(&sel_mutex); 501 502 length = task_has_security(current, SECURITY__LOAD_POLICY); 503 if (length) 504 goto out; 505 506 /* No partial writes. */ 507 length = -EINVAL; 508 if (*ppos != 0) 509 goto out; 510 511 length = -EFBIG; 512 if (count > 64 * 1024 * 1024) 513 goto out; 514 515 length = -ENOMEM; 516 data = vmalloc(count); 517 if (!data) 518 goto out; 519 520 length = -EFAULT; 521 if (copy_from_user(data, buf, count) != 0) 522 goto out; 523 524 length = security_load_policy(data, count); 525 if (length) 526 goto out; 527 528 length = sel_make_bools(); 529 if (length) 530 goto out1; 531 532 length = sel_make_classes(); 533 if (length) 534 goto out1; 535 536 length = sel_make_policycap(); 537 if (length) 538 goto out1; 539 540 length = count; 541 542 out1: 543 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD, 544 "policy loaded auid=%u ses=%u", 545 from_kuid(&init_user_ns, audit_get_loginuid(current)), 546 audit_get_sessionid(current)); 547 out: 548 mutex_unlock(&sel_mutex); 549 vfree(data); 550 return length; 551 } 552 553 static const struct file_operations sel_load_ops = { 554 .write = sel_write_load, 555 .llseek = generic_file_llseek, 556 }; 557 558 static ssize_t sel_write_context(struct file *file, char *buf, size_t size) 559 { 560 char *canon = NULL; 561 u32 sid, len; 562 ssize_t length; 563 564 length = task_has_security(current, SECURITY__CHECK_CONTEXT); 565 if (length) 566 goto out; 567 568 length = security_context_to_sid(buf, size, &sid, GFP_KERNEL); 569 if (length) 570 goto out; 571 572 length = security_sid_to_context(sid, &canon, &len); 573 if (length) 574 goto out; 575 576 length = -ERANGE; 577 if (len > SIMPLE_TRANSACTION_LIMIT) { 578 printk(KERN_ERR "SELinux: %s: context size (%u) exceeds " 579 "payload max\n", __func__, len); 580 goto out; 581 } 582 583 memcpy(buf, canon, len); 584 length = len; 585 out: 586 kfree(canon); 587 return length; 588 } 589 590 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf, 591 size_t count, loff_t *ppos) 592 { 593 char tmpbuf[TMPBUFLEN]; 594 ssize_t length; 595 596 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot); 597 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 598 } 599 600 static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf, 601 size_t count, loff_t *ppos) 602 { 603 char *page; 604 ssize_t length; 605 unsigned int new_value; 606 607 length = task_has_security(current, SECURITY__SETCHECKREQPROT); 608 if (length) 609 return length; 610 611 if (count >= PAGE_SIZE) 612 return -ENOMEM; 613 614 /* No partial writes. */ 615 if (*ppos != 0) 616 return -EINVAL; 617 618 page = memdup_user_nul(buf, count); 619 if (IS_ERR(page)) 620 return PTR_ERR(page); 621 622 length = -EINVAL; 623 if (sscanf(page, "%u", &new_value) != 1) 624 goto out; 625 626 selinux_checkreqprot = new_value ? 1 : 0; 627 length = count; 628 out: 629 kfree(page); 630 return length; 631 } 632 static const struct file_operations sel_checkreqprot_ops = { 633 .read = sel_read_checkreqprot, 634 .write = sel_write_checkreqprot, 635 .llseek = generic_file_llseek, 636 }; 637 638 static ssize_t sel_write_validatetrans(struct file *file, 639 const char __user *buf, 640 size_t count, loff_t *ppos) 641 { 642 char *oldcon = NULL, *newcon = NULL, *taskcon = NULL; 643 char *req = NULL; 644 u32 osid, nsid, tsid; 645 u16 tclass; 646 int rc; 647 648 rc = task_has_security(current, SECURITY__VALIDATE_TRANS); 649 if (rc) 650 goto out; 651 652 rc = -ENOMEM; 653 if (count >= PAGE_SIZE) 654 goto out; 655 656 /* No partial writes. */ 657 rc = -EINVAL; 658 if (*ppos != 0) 659 goto out; 660 661 rc = -ENOMEM; 662 req = kzalloc(count + 1, GFP_KERNEL); 663 if (!req) 664 goto out; 665 666 rc = -EFAULT; 667 if (copy_from_user(req, buf, count)) 668 goto out; 669 670 rc = -ENOMEM; 671 oldcon = kzalloc(count + 1, GFP_KERNEL); 672 if (!oldcon) 673 goto out; 674 675 newcon = kzalloc(count + 1, GFP_KERNEL); 676 if (!newcon) 677 goto out; 678 679 taskcon = kzalloc(count + 1, GFP_KERNEL); 680 if (!taskcon) 681 goto out; 682 683 rc = -EINVAL; 684 if (sscanf(req, "%s %s %hu %s", oldcon, newcon, &tclass, taskcon) != 4) 685 goto out; 686 687 rc = security_context_str_to_sid(oldcon, &osid, GFP_KERNEL); 688 if (rc) 689 goto out; 690 691 rc = security_context_str_to_sid(newcon, &nsid, GFP_KERNEL); 692 if (rc) 693 goto out; 694 695 rc = security_context_str_to_sid(taskcon, &tsid, GFP_KERNEL); 696 if (rc) 697 goto out; 698 699 rc = security_validate_transition_user(osid, nsid, tsid, tclass); 700 if (!rc) 701 rc = count; 702 out: 703 kfree(req); 704 kfree(oldcon); 705 kfree(newcon); 706 kfree(taskcon); 707 return rc; 708 } 709 710 static const struct file_operations sel_transition_ops = { 711 .write = sel_write_validatetrans, 712 .llseek = generic_file_llseek, 713 }; 714 715 /* 716 * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c 717 */ 718 static ssize_t sel_write_access(struct file *file, char *buf, size_t size); 719 static ssize_t sel_write_create(struct file *file, char *buf, size_t size); 720 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size); 721 static ssize_t sel_write_user(struct file *file, char *buf, size_t size); 722 static ssize_t sel_write_member(struct file *file, char *buf, size_t size); 723 724 static ssize_t (*write_op[])(struct file *, char *, size_t) = { 725 [SEL_ACCESS] = sel_write_access, 726 [SEL_CREATE] = sel_write_create, 727 [SEL_RELABEL] = sel_write_relabel, 728 [SEL_USER] = sel_write_user, 729 [SEL_MEMBER] = sel_write_member, 730 [SEL_CONTEXT] = sel_write_context, 731 }; 732 733 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos) 734 { 735 ino_t ino = file_inode(file)->i_ino; 736 char *data; 737 ssize_t rv; 738 739 if (ino >= ARRAY_SIZE(write_op) || !write_op[ino]) 740 return -EINVAL; 741 742 data = simple_transaction_get(file, buf, size); 743 if (IS_ERR(data)) 744 return PTR_ERR(data); 745 746 rv = write_op[ino](file, data, size); 747 if (rv > 0) { 748 simple_transaction_set(file, rv); 749 rv = size; 750 } 751 return rv; 752 } 753 754 static const struct file_operations transaction_ops = { 755 .write = selinux_transaction_write, 756 .read = simple_transaction_read, 757 .release = simple_transaction_release, 758 .llseek = generic_file_llseek, 759 }; 760 761 /* 762 * payload - write methods 763 * If the method has a response, the response should be put in buf, 764 * and the length returned. Otherwise return 0 or and -error. 765 */ 766 767 static ssize_t sel_write_access(struct file *file, char *buf, size_t size) 768 { 769 char *scon = NULL, *tcon = NULL; 770 u32 ssid, tsid; 771 u16 tclass; 772 struct av_decision avd; 773 ssize_t length; 774 775 length = task_has_security(current, SECURITY__COMPUTE_AV); 776 if (length) 777 goto out; 778 779 length = -ENOMEM; 780 scon = kzalloc(size + 1, GFP_KERNEL); 781 if (!scon) 782 goto out; 783 784 length = -ENOMEM; 785 tcon = kzalloc(size + 1, GFP_KERNEL); 786 if (!tcon) 787 goto out; 788 789 length = -EINVAL; 790 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3) 791 goto out; 792 793 length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL); 794 if (length) 795 goto out; 796 797 length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL); 798 if (length) 799 goto out; 800 801 security_compute_av_user(ssid, tsid, tclass, &avd); 802 803 length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, 804 "%x %x %x %x %u %x", 805 avd.allowed, 0xffffffff, 806 avd.auditallow, avd.auditdeny, 807 avd.seqno, avd.flags); 808 out: 809 kfree(tcon); 810 kfree(scon); 811 return length; 812 } 813 814 static ssize_t sel_write_create(struct file *file, char *buf, size_t size) 815 { 816 char *scon = NULL, *tcon = NULL; 817 char *namebuf = NULL, *objname = NULL; 818 u32 ssid, tsid, newsid; 819 u16 tclass; 820 ssize_t length; 821 char *newcon = NULL; 822 u32 len; 823 int nargs; 824 825 length = task_has_security(current, SECURITY__COMPUTE_CREATE); 826 if (length) 827 goto out; 828 829 length = -ENOMEM; 830 scon = kzalloc(size + 1, GFP_KERNEL); 831 if (!scon) 832 goto out; 833 834 length = -ENOMEM; 835 tcon = kzalloc(size + 1, GFP_KERNEL); 836 if (!tcon) 837 goto out; 838 839 length = -ENOMEM; 840 namebuf = kzalloc(size + 1, GFP_KERNEL); 841 if (!namebuf) 842 goto out; 843 844 length = -EINVAL; 845 nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf); 846 if (nargs < 3 || nargs > 4) 847 goto out; 848 if (nargs == 4) { 849 /* 850 * If and when the name of new object to be queried contains 851 * either whitespace or multibyte characters, they shall be 852 * encoded based on the percentage-encoding rule. 853 * If not encoded, the sscanf logic picks up only left-half 854 * of the supplied name; splitted by a whitespace unexpectedly. 855 */ 856 char *r, *w; 857 int c1, c2; 858 859 r = w = namebuf; 860 do { 861 c1 = *r++; 862 if (c1 == '+') 863 c1 = ' '; 864 else if (c1 == '%') { 865 c1 = hex_to_bin(*r++); 866 if (c1 < 0) 867 goto out; 868 c2 = hex_to_bin(*r++); 869 if (c2 < 0) 870 goto out; 871 c1 = (c1 << 4) | c2; 872 } 873 *w++ = c1; 874 } while (c1 != '\0'); 875 876 objname = namebuf; 877 } 878 879 length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL); 880 if (length) 881 goto out; 882 883 length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL); 884 if (length) 885 goto out; 886 887 length = security_transition_sid_user(ssid, tsid, tclass, 888 objname, &newsid); 889 if (length) 890 goto out; 891 892 length = security_sid_to_context(newsid, &newcon, &len); 893 if (length) 894 goto out; 895 896 length = -ERANGE; 897 if (len > SIMPLE_TRANSACTION_LIMIT) { 898 printk(KERN_ERR "SELinux: %s: context size (%u) exceeds " 899 "payload max\n", __func__, len); 900 goto out; 901 } 902 903 memcpy(buf, newcon, len); 904 length = len; 905 out: 906 kfree(newcon); 907 kfree(namebuf); 908 kfree(tcon); 909 kfree(scon); 910 return length; 911 } 912 913 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size) 914 { 915 char *scon = NULL, *tcon = NULL; 916 u32 ssid, tsid, newsid; 917 u16 tclass; 918 ssize_t length; 919 char *newcon = NULL; 920 u32 len; 921 922 length = task_has_security(current, SECURITY__COMPUTE_RELABEL); 923 if (length) 924 goto out; 925 926 length = -ENOMEM; 927 scon = kzalloc(size + 1, GFP_KERNEL); 928 if (!scon) 929 goto out; 930 931 length = -ENOMEM; 932 tcon = kzalloc(size + 1, GFP_KERNEL); 933 if (!tcon) 934 goto out; 935 936 length = -EINVAL; 937 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3) 938 goto out; 939 940 length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL); 941 if (length) 942 goto out; 943 944 length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL); 945 if (length) 946 goto out; 947 948 length = security_change_sid(ssid, tsid, tclass, &newsid); 949 if (length) 950 goto out; 951 952 length = security_sid_to_context(newsid, &newcon, &len); 953 if (length) 954 goto out; 955 956 length = -ERANGE; 957 if (len > SIMPLE_TRANSACTION_LIMIT) 958 goto out; 959 960 memcpy(buf, newcon, len); 961 length = len; 962 out: 963 kfree(newcon); 964 kfree(tcon); 965 kfree(scon); 966 return length; 967 } 968 969 static ssize_t sel_write_user(struct file *file, char *buf, size_t size) 970 { 971 char *con = NULL, *user = NULL, *ptr; 972 u32 sid, *sids = NULL; 973 ssize_t length; 974 char *newcon; 975 int i, rc; 976 u32 len, nsids; 977 978 length = task_has_security(current, SECURITY__COMPUTE_USER); 979 if (length) 980 goto out; 981 982 length = -ENOMEM; 983 con = kzalloc(size + 1, GFP_KERNEL); 984 if (!con) 985 goto out; 986 987 length = -ENOMEM; 988 user = kzalloc(size + 1, GFP_KERNEL); 989 if (!user) 990 goto out; 991 992 length = -EINVAL; 993 if (sscanf(buf, "%s %s", con, user) != 2) 994 goto out; 995 996 length = security_context_str_to_sid(con, &sid, GFP_KERNEL); 997 if (length) 998 goto out; 999 1000 length = security_get_user_sids(sid, user, &sids, &nsids); 1001 if (length) 1002 goto out; 1003 1004 length = sprintf(buf, "%u", nsids) + 1; 1005 ptr = buf + length; 1006 for (i = 0; i < nsids; i++) { 1007 rc = security_sid_to_context(sids[i], &newcon, &len); 1008 if (rc) { 1009 length = rc; 1010 goto out; 1011 } 1012 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) { 1013 kfree(newcon); 1014 length = -ERANGE; 1015 goto out; 1016 } 1017 memcpy(ptr, newcon, len); 1018 kfree(newcon); 1019 ptr += len; 1020 length += len; 1021 } 1022 out: 1023 kfree(sids); 1024 kfree(user); 1025 kfree(con); 1026 return length; 1027 } 1028 1029 static ssize_t sel_write_member(struct file *file, char *buf, size_t size) 1030 { 1031 char *scon = NULL, *tcon = NULL; 1032 u32 ssid, tsid, newsid; 1033 u16 tclass; 1034 ssize_t length; 1035 char *newcon = NULL; 1036 u32 len; 1037 1038 length = task_has_security(current, SECURITY__COMPUTE_MEMBER); 1039 if (length) 1040 goto out; 1041 1042 length = -ENOMEM; 1043 scon = kzalloc(size + 1, GFP_KERNEL); 1044 if (!scon) 1045 goto out; 1046 1047 length = -ENOMEM; 1048 tcon = kzalloc(size + 1, GFP_KERNEL); 1049 if (!tcon) 1050 goto out; 1051 1052 length = -EINVAL; 1053 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3) 1054 goto out; 1055 1056 length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL); 1057 if (length) 1058 goto out; 1059 1060 length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL); 1061 if (length) 1062 goto out; 1063 1064 length = security_member_sid(ssid, tsid, tclass, &newsid); 1065 if (length) 1066 goto out; 1067 1068 length = security_sid_to_context(newsid, &newcon, &len); 1069 if (length) 1070 goto out; 1071 1072 length = -ERANGE; 1073 if (len > SIMPLE_TRANSACTION_LIMIT) { 1074 printk(KERN_ERR "SELinux: %s: context size (%u) exceeds " 1075 "payload max\n", __func__, len); 1076 goto out; 1077 } 1078 1079 memcpy(buf, newcon, len); 1080 length = len; 1081 out: 1082 kfree(newcon); 1083 kfree(tcon); 1084 kfree(scon); 1085 return length; 1086 } 1087 1088 static struct inode *sel_make_inode(struct super_block *sb, int mode) 1089 { 1090 struct inode *ret = new_inode(sb); 1091 1092 if (ret) { 1093 ret->i_mode = mode; 1094 ret->i_atime = ret->i_mtime = ret->i_ctime = current_time(ret); 1095 } 1096 return ret; 1097 } 1098 1099 static ssize_t sel_read_bool(struct file *filep, char __user *buf, 1100 size_t count, loff_t *ppos) 1101 { 1102 char *page = NULL; 1103 ssize_t length; 1104 ssize_t ret; 1105 int cur_enforcing; 1106 unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK; 1107 const char *name = filep->f_path.dentry->d_name.name; 1108 1109 mutex_lock(&sel_mutex); 1110 1111 ret = -EINVAL; 1112 if (index >= bool_num || strcmp(name, bool_pending_names[index])) 1113 goto out; 1114 1115 ret = -ENOMEM; 1116 page = (char *)get_zeroed_page(GFP_KERNEL); 1117 if (!page) 1118 goto out; 1119 1120 cur_enforcing = security_get_bool_value(index); 1121 if (cur_enforcing < 0) { 1122 ret = cur_enforcing; 1123 goto out; 1124 } 1125 length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing, 1126 bool_pending_values[index]); 1127 ret = simple_read_from_buffer(buf, count, ppos, page, length); 1128 out: 1129 mutex_unlock(&sel_mutex); 1130 free_page((unsigned long)page); 1131 return ret; 1132 } 1133 1134 static ssize_t sel_write_bool(struct file *filep, const char __user *buf, 1135 size_t count, loff_t *ppos) 1136 { 1137 char *page = NULL; 1138 ssize_t length; 1139 int new_value; 1140 unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK; 1141 const char *name = filep->f_path.dentry->d_name.name; 1142 1143 mutex_lock(&sel_mutex); 1144 1145 length = task_has_security(current, SECURITY__SETBOOL); 1146 if (length) 1147 goto out; 1148 1149 length = -EINVAL; 1150 if (index >= bool_num || strcmp(name, bool_pending_names[index])) 1151 goto out; 1152 1153 length = -ENOMEM; 1154 if (count >= PAGE_SIZE) 1155 goto out; 1156 1157 /* No partial writes. */ 1158 length = -EINVAL; 1159 if (*ppos != 0) 1160 goto out; 1161 1162 page = memdup_user_nul(buf, count); 1163 if (IS_ERR(page)) { 1164 length = PTR_ERR(page); 1165 page = NULL; 1166 goto out; 1167 } 1168 1169 length = -EINVAL; 1170 if (sscanf(page, "%d", &new_value) != 1) 1171 goto out; 1172 1173 if (new_value) 1174 new_value = 1; 1175 1176 bool_pending_values[index] = new_value; 1177 length = count; 1178 1179 out: 1180 mutex_unlock(&sel_mutex); 1181 kfree(page); 1182 return length; 1183 } 1184 1185 static const struct file_operations sel_bool_ops = { 1186 .read = sel_read_bool, 1187 .write = sel_write_bool, 1188 .llseek = generic_file_llseek, 1189 }; 1190 1191 static ssize_t sel_commit_bools_write(struct file *filep, 1192 const char __user *buf, 1193 size_t count, loff_t *ppos) 1194 { 1195 char *page = NULL; 1196 ssize_t length; 1197 int new_value; 1198 1199 mutex_lock(&sel_mutex); 1200 1201 length = task_has_security(current, SECURITY__SETBOOL); 1202 if (length) 1203 goto out; 1204 1205 length = -ENOMEM; 1206 if (count >= PAGE_SIZE) 1207 goto out; 1208 1209 /* No partial writes. */ 1210 length = -EINVAL; 1211 if (*ppos != 0) 1212 goto out; 1213 1214 page = memdup_user_nul(buf, count); 1215 if (IS_ERR(page)) { 1216 length = PTR_ERR(page); 1217 page = NULL; 1218 goto out; 1219 } 1220 1221 length = -EINVAL; 1222 if (sscanf(page, "%d", &new_value) != 1) 1223 goto out; 1224 1225 length = 0; 1226 if (new_value && bool_pending_values) 1227 length = security_set_bools(bool_num, bool_pending_values); 1228 1229 if (!length) 1230 length = count; 1231 1232 out: 1233 mutex_unlock(&sel_mutex); 1234 kfree(page); 1235 return length; 1236 } 1237 1238 static const struct file_operations sel_commit_bools_ops = { 1239 .write = sel_commit_bools_write, 1240 .llseek = generic_file_llseek, 1241 }; 1242 1243 static void sel_remove_entries(struct dentry *de) 1244 { 1245 d_genocide(de); 1246 shrink_dcache_parent(de); 1247 } 1248 1249 #define BOOL_DIR_NAME "booleans" 1250 1251 static int sel_make_bools(void) 1252 { 1253 int i, ret; 1254 ssize_t len; 1255 struct dentry *dentry = NULL; 1256 struct dentry *dir = bool_dir; 1257 struct inode *inode = NULL; 1258 struct inode_security_struct *isec; 1259 char **names = NULL, *page; 1260 int num; 1261 int *values = NULL; 1262 u32 sid; 1263 1264 /* remove any existing files */ 1265 for (i = 0; i < bool_num; i++) 1266 kfree(bool_pending_names[i]); 1267 kfree(bool_pending_names); 1268 kfree(bool_pending_values); 1269 bool_num = 0; 1270 bool_pending_names = NULL; 1271 bool_pending_values = NULL; 1272 1273 sel_remove_entries(dir); 1274 1275 ret = -ENOMEM; 1276 page = (char *)get_zeroed_page(GFP_KERNEL); 1277 if (!page) 1278 goto out; 1279 1280 ret = security_get_bools(&num, &names, &values); 1281 if (ret) 1282 goto out; 1283 1284 for (i = 0; i < num; i++) { 1285 ret = -ENOMEM; 1286 dentry = d_alloc_name(dir, names[i]); 1287 if (!dentry) 1288 goto out; 1289 1290 ret = -ENOMEM; 1291 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR); 1292 if (!inode) 1293 goto out; 1294 1295 ret = -ENAMETOOLONG; 1296 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]); 1297 if (len >= PAGE_SIZE) 1298 goto out; 1299 1300 isec = (struct inode_security_struct *)inode->i_security; 1301 ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid); 1302 if (ret) 1303 goto out; 1304 1305 isec->sid = sid; 1306 isec->initialized = LABEL_INITIALIZED; 1307 inode->i_fop = &sel_bool_ops; 1308 inode->i_ino = i|SEL_BOOL_INO_OFFSET; 1309 d_add(dentry, inode); 1310 } 1311 bool_num = num; 1312 bool_pending_names = names; 1313 bool_pending_values = values; 1314 1315 free_page((unsigned long)page); 1316 return 0; 1317 out: 1318 free_page((unsigned long)page); 1319 1320 if (names) { 1321 for (i = 0; i < num; i++) 1322 kfree(names[i]); 1323 kfree(names); 1324 } 1325 kfree(values); 1326 sel_remove_entries(dir); 1327 1328 return ret; 1329 } 1330 1331 #define NULL_FILE_NAME "null" 1332 1333 struct path selinux_null; 1334 1335 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf, 1336 size_t count, loff_t *ppos) 1337 { 1338 char tmpbuf[TMPBUFLEN]; 1339 ssize_t length; 1340 1341 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold); 1342 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1343 } 1344 1345 static ssize_t sel_write_avc_cache_threshold(struct file *file, 1346 const char __user *buf, 1347 size_t count, loff_t *ppos) 1348 1349 { 1350 char *page; 1351 ssize_t ret; 1352 unsigned int new_value; 1353 1354 ret = task_has_security(current, SECURITY__SETSECPARAM); 1355 if (ret) 1356 return ret; 1357 1358 if (count >= PAGE_SIZE) 1359 return -ENOMEM; 1360 1361 /* No partial writes. */ 1362 if (*ppos != 0) 1363 return -EINVAL; 1364 1365 page = memdup_user_nul(buf, count); 1366 if (IS_ERR(page)) 1367 return PTR_ERR(page); 1368 1369 ret = -EINVAL; 1370 if (sscanf(page, "%u", &new_value) != 1) 1371 goto out; 1372 1373 avc_cache_threshold = new_value; 1374 1375 ret = count; 1376 out: 1377 kfree(page); 1378 return ret; 1379 } 1380 1381 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf, 1382 size_t count, loff_t *ppos) 1383 { 1384 char *page; 1385 ssize_t length; 1386 1387 page = (char *)__get_free_page(GFP_KERNEL); 1388 if (!page) 1389 return -ENOMEM; 1390 1391 length = avc_get_hash_stats(page); 1392 if (length >= 0) 1393 length = simple_read_from_buffer(buf, count, ppos, page, length); 1394 free_page((unsigned long)page); 1395 1396 return length; 1397 } 1398 1399 static const struct file_operations sel_avc_cache_threshold_ops = { 1400 .read = sel_read_avc_cache_threshold, 1401 .write = sel_write_avc_cache_threshold, 1402 .llseek = generic_file_llseek, 1403 }; 1404 1405 static const struct file_operations sel_avc_hash_stats_ops = { 1406 .read = sel_read_avc_hash_stats, 1407 .llseek = generic_file_llseek, 1408 }; 1409 1410 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS 1411 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx) 1412 { 1413 int cpu; 1414 1415 for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) { 1416 if (!cpu_possible(cpu)) 1417 continue; 1418 *idx = cpu + 1; 1419 return &per_cpu(avc_cache_stats, cpu); 1420 } 1421 return NULL; 1422 } 1423 1424 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos) 1425 { 1426 loff_t n = *pos - 1; 1427 1428 if (*pos == 0) 1429 return SEQ_START_TOKEN; 1430 1431 return sel_avc_get_stat_idx(&n); 1432 } 1433 1434 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos) 1435 { 1436 return sel_avc_get_stat_idx(pos); 1437 } 1438 1439 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v) 1440 { 1441 struct avc_cache_stats *st = v; 1442 1443 if (v == SEQ_START_TOKEN) 1444 seq_printf(seq, "lookups hits misses allocations reclaims " 1445 "frees\n"); 1446 else { 1447 unsigned int lookups = st->lookups; 1448 unsigned int misses = st->misses; 1449 unsigned int hits = lookups - misses; 1450 seq_printf(seq, "%u %u %u %u %u %u\n", lookups, 1451 hits, misses, st->allocations, 1452 st->reclaims, st->frees); 1453 } 1454 return 0; 1455 } 1456 1457 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v) 1458 { } 1459 1460 static const struct seq_operations sel_avc_cache_stats_seq_ops = { 1461 .start = sel_avc_stats_seq_start, 1462 .next = sel_avc_stats_seq_next, 1463 .show = sel_avc_stats_seq_show, 1464 .stop = sel_avc_stats_seq_stop, 1465 }; 1466 1467 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file) 1468 { 1469 return seq_open(file, &sel_avc_cache_stats_seq_ops); 1470 } 1471 1472 static const struct file_operations sel_avc_cache_stats_ops = { 1473 .open = sel_open_avc_cache_stats, 1474 .read = seq_read, 1475 .llseek = seq_lseek, 1476 .release = seq_release, 1477 }; 1478 #endif 1479 1480 static int sel_make_avc_files(struct dentry *dir) 1481 { 1482 int i; 1483 static struct tree_descr files[] = { 1484 { "cache_threshold", 1485 &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR }, 1486 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO }, 1487 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS 1488 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO }, 1489 #endif 1490 }; 1491 1492 for (i = 0; i < ARRAY_SIZE(files); i++) { 1493 struct inode *inode; 1494 struct dentry *dentry; 1495 1496 dentry = d_alloc_name(dir, files[i].name); 1497 if (!dentry) 1498 return -ENOMEM; 1499 1500 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode); 1501 if (!inode) 1502 return -ENOMEM; 1503 1504 inode->i_fop = files[i].ops; 1505 inode->i_ino = ++sel_last_ino; 1506 d_add(dentry, inode); 1507 } 1508 1509 return 0; 1510 } 1511 1512 static ssize_t sel_read_initcon(struct file *file, char __user *buf, 1513 size_t count, loff_t *ppos) 1514 { 1515 char *con; 1516 u32 sid, len; 1517 ssize_t ret; 1518 1519 sid = file_inode(file)->i_ino&SEL_INO_MASK; 1520 ret = security_sid_to_context(sid, &con, &len); 1521 if (ret) 1522 return ret; 1523 1524 ret = simple_read_from_buffer(buf, count, ppos, con, len); 1525 kfree(con); 1526 return ret; 1527 } 1528 1529 static const struct file_operations sel_initcon_ops = { 1530 .read = sel_read_initcon, 1531 .llseek = generic_file_llseek, 1532 }; 1533 1534 static int sel_make_initcon_files(struct dentry *dir) 1535 { 1536 int i; 1537 1538 for (i = 1; i <= SECINITSID_NUM; i++) { 1539 struct inode *inode; 1540 struct dentry *dentry; 1541 dentry = d_alloc_name(dir, security_get_initial_sid_context(i)); 1542 if (!dentry) 1543 return -ENOMEM; 1544 1545 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO); 1546 if (!inode) 1547 return -ENOMEM; 1548 1549 inode->i_fop = &sel_initcon_ops; 1550 inode->i_ino = i|SEL_INITCON_INO_OFFSET; 1551 d_add(dentry, inode); 1552 } 1553 1554 return 0; 1555 } 1556 1557 static inline unsigned long sel_class_to_ino(u16 class) 1558 { 1559 return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET; 1560 } 1561 1562 static inline u16 sel_ino_to_class(unsigned long ino) 1563 { 1564 return (ino & SEL_INO_MASK) / (SEL_VEC_MAX + 1); 1565 } 1566 1567 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm) 1568 { 1569 return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET; 1570 } 1571 1572 static inline u32 sel_ino_to_perm(unsigned long ino) 1573 { 1574 return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1); 1575 } 1576 1577 static ssize_t sel_read_class(struct file *file, char __user *buf, 1578 size_t count, loff_t *ppos) 1579 { 1580 unsigned long ino = file_inode(file)->i_ino; 1581 char res[TMPBUFLEN]; 1582 ssize_t len = snprintf(res, sizeof(res), "%d", sel_ino_to_class(ino)); 1583 return simple_read_from_buffer(buf, count, ppos, res, len); 1584 } 1585 1586 static const struct file_operations sel_class_ops = { 1587 .read = sel_read_class, 1588 .llseek = generic_file_llseek, 1589 }; 1590 1591 static ssize_t sel_read_perm(struct file *file, char __user *buf, 1592 size_t count, loff_t *ppos) 1593 { 1594 unsigned long ino = file_inode(file)->i_ino; 1595 char res[TMPBUFLEN]; 1596 ssize_t len = snprintf(res, sizeof(res), "%d", sel_ino_to_perm(ino)); 1597 return simple_read_from_buffer(buf, count, ppos, res, len); 1598 } 1599 1600 static const struct file_operations sel_perm_ops = { 1601 .read = sel_read_perm, 1602 .llseek = generic_file_llseek, 1603 }; 1604 1605 static ssize_t sel_read_policycap(struct file *file, char __user *buf, 1606 size_t count, loff_t *ppos) 1607 { 1608 int value; 1609 char tmpbuf[TMPBUFLEN]; 1610 ssize_t length; 1611 unsigned long i_ino = file_inode(file)->i_ino; 1612 1613 value = security_policycap_supported(i_ino & SEL_INO_MASK); 1614 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value); 1615 1616 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1617 } 1618 1619 static const struct file_operations sel_policycap_ops = { 1620 .read = sel_read_policycap, 1621 .llseek = generic_file_llseek, 1622 }; 1623 1624 static int sel_make_perm_files(char *objclass, int classvalue, 1625 struct dentry *dir) 1626 { 1627 int i, rc, nperms; 1628 char **perms; 1629 1630 rc = security_get_permissions(objclass, &perms, &nperms); 1631 if (rc) 1632 return rc; 1633 1634 for (i = 0; i < nperms; i++) { 1635 struct inode *inode; 1636 struct dentry *dentry; 1637 1638 rc = -ENOMEM; 1639 dentry = d_alloc_name(dir, perms[i]); 1640 if (!dentry) 1641 goto out; 1642 1643 rc = -ENOMEM; 1644 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO); 1645 if (!inode) 1646 goto out; 1647 1648 inode->i_fop = &sel_perm_ops; 1649 /* i+1 since perm values are 1-indexed */ 1650 inode->i_ino = sel_perm_to_ino(classvalue, i + 1); 1651 d_add(dentry, inode); 1652 } 1653 rc = 0; 1654 out: 1655 for (i = 0; i < nperms; i++) 1656 kfree(perms[i]); 1657 kfree(perms); 1658 return rc; 1659 } 1660 1661 static int sel_make_class_dir_entries(char *classname, int index, 1662 struct dentry *dir) 1663 { 1664 struct dentry *dentry = NULL; 1665 struct inode *inode = NULL; 1666 int rc; 1667 1668 dentry = d_alloc_name(dir, "index"); 1669 if (!dentry) 1670 return -ENOMEM; 1671 1672 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO); 1673 if (!inode) 1674 return -ENOMEM; 1675 1676 inode->i_fop = &sel_class_ops; 1677 inode->i_ino = sel_class_to_ino(index); 1678 d_add(dentry, inode); 1679 1680 dentry = sel_make_dir(dir, "perms", &last_class_ino); 1681 if (IS_ERR(dentry)) 1682 return PTR_ERR(dentry); 1683 1684 rc = sel_make_perm_files(classname, index, dentry); 1685 1686 return rc; 1687 } 1688 1689 static int sel_make_classes(void) 1690 { 1691 int rc, nclasses, i; 1692 char **classes; 1693 1694 /* delete any existing entries */ 1695 sel_remove_entries(class_dir); 1696 1697 rc = security_get_classes(&classes, &nclasses); 1698 if (rc) 1699 return rc; 1700 1701 /* +2 since classes are 1-indexed */ 1702 last_class_ino = sel_class_to_ino(nclasses + 2); 1703 1704 for (i = 0; i < nclasses; i++) { 1705 struct dentry *class_name_dir; 1706 1707 class_name_dir = sel_make_dir(class_dir, classes[i], 1708 &last_class_ino); 1709 if (IS_ERR(class_name_dir)) { 1710 rc = PTR_ERR(class_name_dir); 1711 goto out; 1712 } 1713 1714 /* i+1 since class values are 1-indexed */ 1715 rc = sel_make_class_dir_entries(classes[i], i + 1, 1716 class_name_dir); 1717 if (rc) 1718 goto out; 1719 } 1720 rc = 0; 1721 out: 1722 for (i = 0; i < nclasses; i++) 1723 kfree(classes[i]); 1724 kfree(classes); 1725 return rc; 1726 } 1727 1728 static int sel_make_policycap(void) 1729 { 1730 unsigned int iter; 1731 struct dentry *dentry = NULL; 1732 struct inode *inode = NULL; 1733 1734 sel_remove_entries(policycap_dir); 1735 1736 for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) { 1737 if (iter < ARRAY_SIZE(policycap_names)) 1738 dentry = d_alloc_name(policycap_dir, 1739 policycap_names[iter]); 1740 else 1741 dentry = d_alloc_name(policycap_dir, "unknown"); 1742 1743 if (dentry == NULL) 1744 return -ENOMEM; 1745 1746 inode = sel_make_inode(policycap_dir->d_sb, S_IFREG | S_IRUGO); 1747 if (inode == NULL) 1748 return -ENOMEM; 1749 1750 inode->i_fop = &sel_policycap_ops; 1751 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET; 1752 d_add(dentry, inode); 1753 } 1754 1755 return 0; 1756 } 1757 1758 static struct dentry *sel_make_dir(struct dentry *dir, const char *name, 1759 unsigned long *ino) 1760 { 1761 struct dentry *dentry = d_alloc_name(dir, name); 1762 struct inode *inode; 1763 1764 if (!dentry) 1765 return ERR_PTR(-ENOMEM); 1766 1767 inode = sel_make_inode(dir->d_sb, S_IFDIR | S_IRUGO | S_IXUGO); 1768 if (!inode) { 1769 dput(dentry); 1770 return ERR_PTR(-ENOMEM); 1771 } 1772 1773 inode->i_op = &simple_dir_inode_operations; 1774 inode->i_fop = &simple_dir_operations; 1775 inode->i_ino = ++(*ino); 1776 /* directory inodes start off with i_nlink == 2 (for "." entry) */ 1777 inc_nlink(inode); 1778 d_add(dentry, inode); 1779 /* bump link count on parent directory, too */ 1780 inc_nlink(d_inode(dir)); 1781 1782 return dentry; 1783 } 1784 1785 static int sel_fill_super(struct super_block *sb, void *data, int silent) 1786 { 1787 int ret; 1788 struct dentry *dentry; 1789 struct inode *inode; 1790 struct inode_security_struct *isec; 1791 1792 static struct tree_descr selinux_files[] = { 1793 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR}, 1794 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR}, 1795 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO}, 1796 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO}, 1797 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO}, 1798 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO}, 1799 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO}, 1800 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO}, 1801 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR}, 1802 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO}, 1803 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR}, 1804 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO}, 1805 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR}, 1806 [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO}, 1807 [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO}, 1808 [SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO}, 1809 [SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUGO}, 1810 [SEL_VALIDATE_TRANS] = {"validatetrans", &sel_transition_ops, 1811 S_IWUGO}, 1812 /* last one */ {""} 1813 }; 1814 ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files); 1815 if (ret) 1816 goto err; 1817 1818 bool_dir = sel_make_dir(sb->s_root, BOOL_DIR_NAME, &sel_last_ino); 1819 if (IS_ERR(bool_dir)) { 1820 ret = PTR_ERR(bool_dir); 1821 bool_dir = NULL; 1822 goto err; 1823 } 1824 1825 ret = -ENOMEM; 1826 dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME); 1827 if (!dentry) 1828 goto err; 1829 1830 ret = -ENOMEM; 1831 inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO); 1832 if (!inode) 1833 goto err; 1834 1835 inode->i_ino = ++sel_last_ino; 1836 isec = (struct inode_security_struct *)inode->i_security; 1837 isec->sid = SECINITSID_DEVNULL; 1838 isec->sclass = SECCLASS_CHR_FILE; 1839 isec->initialized = LABEL_INITIALIZED; 1840 1841 init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3)); 1842 d_add(dentry, inode); 1843 selinux_null.dentry = dentry; 1844 1845 dentry = sel_make_dir(sb->s_root, "avc", &sel_last_ino); 1846 if (IS_ERR(dentry)) { 1847 ret = PTR_ERR(dentry); 1848 goto err; 1849 } 1850 1851 ret = sel_make_avc_files(dentry); 1852 if (ret) 1853 goto err; 1854 1855 dentry = sel_make_dir(sb->s_root, "initial_contexts", &sel_last_ino); 1856 if (IS_ERR(dentry)) { 1857 ret = PTR_ERR(dentry); 1858 goto err; 1859 } 1860 1861 ret = sel_make_initcon_files(dentry); 1862 if (ret) 1863 goto err; 1864 1865 class_dir = sel_make_dir(sb->s_root, "class", &sel_last_ino); 1866 if (IS_ERR(class_dir)) { 1867 ret = PTR_ERR(class_dir); 1868 class_dir = NULL; 1869 goto err; 1870 } 1871 1872 policycap_dir = sel_make_dir(sb->s_root, "policy_capabilities", &sel_last_ino); 1873 if (IS_ERR(policycap_dir)) { 1874 ret = PTR_ERR(policycap_dir); 1875 policycap_dir = NULL; 1876 goto err; 1877 } 1878 return 0; 1879 err: 1880 printk(KERN_ERR "SELinux: %s: failed while creating inodes\n", 1881 __func__); 1882 return ret; 1883 } 1884 1885 static struct dentry *sel_mount(struct file_system_type *fs_type, 1886 int flags, const char *dev_name, void *data) 1887 { 1888 return mount_single(fs_type, flags, data, sel_fill_super); 1889 } 1890 1891 static struct file_system_type sel_fs_type = { 1892 .name = "selinuxfs", 1893 .mount = sel_mount, 1894 .kill_sb = kill_litter_super, 1895 }; 1896 1897 struct vfsmount *selinuxfs_mount; 1898 1899 static int __init init_sel_fs(void) 1900 { 1901 int err; 1902 1903 if (!selinux_enabled) 1904 return 0; 1905 1906 err = sysfs_create_mount_point(fs_kobj, "selinux"); 1907 if (err) 1908 return err; 1909 1910 err = register_filesystem(&sel_fs_type); 1911 if (err) { 1912 sysfs_remove_mount_point(fs_kobj, "selinux"); 1913 return err; 1914 } 1915 1916 selinux_null.mnt = selinuxfs_mount = kern_mount(&sel_fs_type); 1917 if (IS_ERR(selinuxfs_mount)) { 1918 printk(KERN_ERR "selinuxfs: could not mount!\n"); 1919 err = PTR_ERR(selinuxfs_mount); 1920 selinuxfs_mount = NULL; 1921 } 1922 1923 return err; 1924 } 1925 1926 __initcall(init_sel_fs); 1927 1928 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 1929 void exit_sel_fs(void) 1930 { 1931 sysfs_remove_mount_point(fs_kobj, "selinux"); 1932 kern_unmount(selinuxfs_mount); 1933 unregister_filesystem(&sel_fs_type); 1934 } 1935 #endif 1936