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 "extended_socket_class", 49 "always_check_network", 50 "cgroup_seclabel" 51 }; 52 53 unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE; 54 55 static int __init checkreqprot_setup(char *str) 56 { 57 unsigned long checkreqprot; 58 if (!kstrtoul(str, 0, &checkreqprot)) 59 selinux_checkreqprot = checkreqprot ? 1 : 0; 60 return 1; 61 } 62 __setup("checkreqprot=", checkreqprot_setup); 63 64 static DEFINE_MUTEX(sel_mutex); 65 66 /* global data for booleans */ 67 static struct dentry *bool_dir; 68 static int bool_num; 69 static char **bool_pending_names; 70 static int *bool_pending_values; 71 72 /* global data for classes */ 73 static struct dentry *class_dir; 74 static unsigned long last_class_ino; 75 76 static char policy_opened; 77 78 /* global data for policy capabilities */ 79 static struct dentry *policycap_dir; 80 81 enum sel_inos { 82 SEL_ROOT_INO = 2, 83 SEL_LOAD, /* load policy */ 84 SEL_ENFORCE, /* get or set enforcing status */ 85 SEL_CONTEXT, /* validate context */ 86 SEL_ACCESS, /* compute access decision */ 87 SEL_CREATE, /* compute create labeling decision */ 88 SEL_RELABEL, /* compute relabeling decision */ 89 SEL_USER, /* compute reachable user contexts */ 90 SEL_POLICYVERS, /* return policy version for this kernel */ 91 SEL_COMMIT_BOOLS, /* commit new boolean values */ 92 SEL_MLS, /* return if MLS policy is enabled */ 93 SEL_DISABLE, /* disable SELinux until next reboot */ 94 SEL_MEMBER, /* compute polyinstantiation membership decision */ 95 SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */ 96 SEL_COMPAT_NET, /* whether to use old compat network packet controls */ 97 SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */ 98 SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */ 99 SEL_STATUS, /* export current status using mmap() */ 100 SEL_POLICY, /* allow userspace to read the in kernel policy */ 101 SEL_VALIDATE_TRANS, /* compute validatetrans decision */ 102 SEL_INO_NEXT, /* The next inode number to use */ 103 }; 104 105 static unsigned long sel_last_ino = SEL_INO_NEXT - 1; 106 107 #define SEL_INITCON_INO_OFFSET 0x01000000 108 #define SEL_BOOL_INO_OFFSET 0x02000000 109 #define SEL_CLASS_INO_OFFSET 0x04000000 110 #define SEL_POLICYCAP_INO_OFFSET 0x08000000 111 #define SEL_INO_MASK 0x00ffffff 112 113 #define TMPBUFLEN 12 114 static ssize_t sel_read_enforce(struct file *filp, char __user *buf, 115 size_t count, loff_t *ppos) 116 { 117 char tmpbuf[TMPBUFLEN]; 118 ssize_t length; 119 120 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing); 121 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 122 } 123 124 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 125 static ssize_t sel_write_enforce(struct file *file, const char __user *buf, 126 size_t count, loff_t *ppos) 127 128 { 129 char *page = NULL; 130 ssize_t length; 131 int new_value; 132 133 if (count >= PAGE_SIZE) 134 return -ENOMEM; 135 136 /* No partial writes. */ 137 if (*ppos != 0) 138 return -EINVAL; 139 140 page = memdup_user_nul(buf, count); 141 if (IS_ERR(page)) 142 return PTR_ERR(page); 143 144 length = -EINVAL; 145 if (sscanf(page, "%d", &new_value) != 1) 146 goto out; 147 148 new_value = !!new_value; 149 150 if (new_value != selinux_enforcing) { 151 length = avc_has_perm(current_sid(), SECINITSID_SECURITY, 152 SECCLASS_SECURITY, SECURITY__SETENFORCE, 153 NULL); 154 if (length) 155 goto out; 156 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS, 157 "enforcing=%d old_enforcing=%d auid=%u ses=%u", 158 new_value, selinux_enforcing, 159 from_kuid(&init_user_ns, audit_get_loginuid(current)), 160 audit_get_sessionid(current)); 161 selinux_enforcing = new_value; 162 if (selinux_enforcing) 163 avc_ss_reset(0); 164 selnl_notify_setenforce(selinux_enforcing); 165 selinux_status_update_setenforce(selinux_enforcing); 166 } 167 length = count; 168 out: 169 kfree(page); 170 return length; 171 } 172 #else 173 #define sel_write_enforce NULL 174 #endif 175 176 static const struct file_operations sel_enforce_ops = { 177 .read = sel_read_enforce, 178 .write = sel_write_enforce, 179 .llseek = generic_file_llseek, 180 }; 181 182 static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf, 183 size_t count, loff_t *ppos) 184 { 185 char tmpbuf[TMPBUFLEN]; 186 ssize_t length; 187 ino_t ino = file_inode(filp)->i_ino; 188 int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ? 189 security_get_reject_unknown() : !security_get_allow_unknown(); 190 191 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown); 192 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 193 } 194 195 static const struct file_operations sel_handle_unknown_ops = { 196 .read = sel_read_handle_unknown, 197 .llseek = generic_file_llseek, 198 }; 199 200 static int sel_open_handle_status(struct inode *inode, struct file *filp) 201 { 202 struct page *status = selinux_kernel_status_page(); 203 204 if (!status) 205 return -ENOMEM; 206 207 filp->private_data = status; 208 209 return 0; 210 } 211 212 static ssize_t sel_read_handle_status(struct file *filp, char __user *buf, 213 size_t count, loff_t *ppos) 214 { 215 struct page *status = filp->private_data; 216 217 BUG_ON(!status); 218 219 return simple_read_from_buffer(buf, count, ppos, 220 page_address(status), 221 sizeof(struct selinux_kernel_status)); 222 } 223 224 static int sel_mmap_handle_status(struct file *filp, 225 struct vm_area_struct *vma) 226 { 227 struct page *status = filp->private_data; 228 unsigned long size = vma->vm_end - vma->vm_start; 229 230 BUG_ON(!status); 231 232 /* only allows one page from the head */ 233 if (vma->vm_pgoff > 0 || size != PAGE_SIZE) 234 return -EIO; 235 /* disallow writable mapping */ 236 if (vma->vm_flags & VM_WRITE) 237 return -EPERM; 238 /* disallow mprotect() turns it into writable */ 239 vma->vm_flags &= ~VM_MAYWRITE; 240 241 return remap_pfn_range(vma, vma->vm_start, 242 page_to_pfn(status), 243 size, vma->vm_page_prot); 244 } 245 246 static const struct file_operations sel_handle_status_ops = { 247 .open = sel_open_handle_status, 248 .read = sel_read_handle_status, 249 .mmap = sel_mmap_handle_status, 250 .llseek = generic_file_llseek, 251 }; 252 253 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 254 static ssize_t sel_write_disable(struct file *file, const char __user *buf, 255 size_t count, loff_t *ppos) 256 257 { 258 char *page; 259 ssize_t length; 260 int new_value; 261 262 if (count >= PAGE_SIZE) 263 return -ENOMEM; 264 265 /* No partial writes. */ 266 if (*ppos != 0) 267 return -EINVAL; 268 269 page = memdup_user_nul(buf, count); 270 if (IS_ERR(page)) 271 return PTR_ERR(page); 272 273 length = -EINVAL; 274 if (sscanf(page, "%d", &new_value) != 1) 275 goto out; 276 277 if (new_value) { 278 length = selinux_disable(); 279 if (length) 280 goto out; 281 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS, 282 "selinux=0 auid=%u ses=%u", 283 from_kuid(&init_user_ns, audit_get_loginuid(current)), 284 audit_get_sessionid(current)); 285 } 286 287 length = count; 288 out: 289 kfree(page); 290 return length; 291 } 292 #else 293 #define sel_write_disable NULL 294 #endif 295 296 static const struct file_operations sel_disable_ops = { 297 .write = sel_write_disable, 298 .llseek = generic_file_llseek, 299 }; 300 301 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf, 302 size_t count, loff_t *ppos) 303 { 304 char tmpbuf[TMPBUFLEN]; 305 ssize_t length; 306 307 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX); 308 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 309 } 310 311 static const struct file_operations sel_policyvers_ops = { 312 .read = sel_read_policyvers, 313 .llseek = generic_file_llseek, 314 }; 315 316 /* declaration for sel_write_load */ 317 static int sel_make_bools(void); 318 static int sel_make_classes(void); 319 static int sel_make_policycap(void); 320 321 /* declaration for sel_make_class_dirs */ 322 static struct dentry *sel_make_dir(struct dentry *dir, const char *name, 323 unsigned long *ino); 324 325 static ssize_t sel_read_mls(struct file *filp, char __user *buf, 326 size_t count, loff_t *ppos) 327 { 328 char tmpbuf[TMPBUFLEN]; 329 ssize_t length; 330 331 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", 332 security_mls_enabled()); 333 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 334 } 335 336 static const struct file_operations sel_mls_ops = { 337 .read = sel_read_mls, 338 .llseek = generic_file_llseek, 339 }; 340 341 struct policy_load_memory { 342 size_t len; 343 void *data; 344 }; 345 346 static int sel_open_policy(struct inode *inode, struct file *filp) 347 { 348 struct policy_load_memory *plm = NULL; 349 int rc; 350 351 BUG_ON(filp->private_data); 352 353 mutex_lock(&sel_mutex); 354 355 rc = avc_has_perm(current_sid(), SECINITSID_SECURITY, 356 SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL); 357 if (rc) 358 goto err; 359 360 rc = -EBUSY; 361 if (policy_opened) 362 goto err; 363 364 rc = -ENOMEM; 365 plm = kzalloc(sizeof(*plm), GFP_KERNEL); 366 if (!plm) 367 goto err; 368 369 if (i_size_read(inode) != security_policydb_len()) { 370 inode_lock(inode); 371 i_size_write(inode, security_policydb_len()); 372 inode_unlock(inode); 373 } 374 375 rc = security_read_policy(&plm->data, &plm->len); 376 if (rc) 377 goto err; 378 379 policy_opened = 1; 380 381 filp->private_data = plm; 382 383 mutex_unlock(&sel_mutex); 384 385 return 0; 386 err: 387 mutex_unlock(&sel_mutex); 388 389 if (plm) 390 vfree(plm->data); 391 kfree(plm); 392 return rc; 393 } 394 395 static int sel_release_policy(struct inode *inode, struct file *filp) 396 { 397 struct policy_load_memory *plm = filp->private_data; 398 399 BUG_ON(!plm); 400 401 policy_opened = 0; 402 403 vfree(plm->data); 404 kfree(plm); 405 406 return 0; 407 } 408 409 static ssize_t sel_read_policy(struct file *filp, char __user *buf, 410 size_t count, loff_t *ppos) 411 { 412 struct policy_load_memory *plm = filp->private_data; 413 int ret; 414 415 mutex_lock(&sel_mutex); 416 417 ret = avc_has_perm(current_sid(), SECINITSID_SECURITY, 418 SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL); 419 if (ret) 420 goto out; 421 422 ret = simple_read_from_buffer(buf, count, ppos, plm->data, plm->len); 423 out: 424 mutex_unlock(&sel_mutex); 425 return ret; 426 } 427 428 static int sel_mmap_policy_fault(struct vm_fault *vmf) 429 { 430 struct policy_load_memory *plm = vmf->vma->vm_file->private_data; 431 unsigned long offset; 432 struct page *page; 433 434 if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE)) 435 return VM_FAULT_SIGBUS; 436 437 offset = vmf->pgoff << PAGE_SHIFT; 438 if (offset >= roundup(plm->len, PAGE_SIZE)) 439 return VM_FAULT_SIGBUS; 440 441 page = vmalloc_to_page(plm->data + offset); 442 get_page(page); 443 444 vmf->page = page; 445 446 return 0; 447 } 448 449 static const struct vm_operations_struct sel_mmap_policy_ops = { 450 .fault = sel_mmap_policy_fault, 451 .page_mkwrite = sel_mmap_policy_fault, 452 }; 453 454 static int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma) 455 { 456 if (vma->vm_flags & VM_SHARED) { 457 /* do not allow mprotect to make mapping writable */ 458 vma->vm_flags &= ~VM_MAYWRITE; 459 460 if (vma->vm_flags & VM_WRITE) 461 return -EACCES; 462 } 463 464 vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP; 465 vma->vm_ops = &sel_mmap_policy_ops; 466 467 return 0; 468 } 469 470 static const struct file_operations sel_policy_ops = { 471 .open = sel_open_policy, 472 .read = sel_read_policy, 473 .mmap = sel_mmap_policy, 474 .release = sel_release_policy, 475 .llseek = generic_file_llseek, 476 }; 477 478 static ssize_t sel_write_load(struct file *file, const char __user *buf, 479 size_t count, loff_t *ppos) 480 481 { 482 ssize_t length; 483 void *data = NULL; 484 485 mutex_lock(&sel_mutex); 486 487 length = avc_has_perm(current_sid(), SECINITSID_SECURITY, 488 SECCLASS_SECURITY, SECURITY__LOAD_POLICY, NULL); 489 if (length) 490 goto out; 491 492 /* No partial writes. */ 493 length = -EINVAL; 494 if (*ppos != 0) 495 goto out; 496 497 length = -EFBIG; 498 if (count > 64 * 1024 * 1024) 499 goto out; 500 501 length = -ENOMEM; 502 data = vmalloc(count); 503 if (!data) 504 goto out; 505 506 length = -EFAULT; 507 if (copy_from_user(data, buf, count) != 0) 508 goto out; 509 510 length = security_load_policy(data, count); 511 if (length) { 512 pr_warn_ratelimited("SELinux: failed to load policy\n"); 513 goto out; 514 } 515 516 length = sel_make_bools(); 517 if (length) { 518 pr_err("SELinux: failed to load policy booleans\n"); 519 goto out1; 520 } 521 522 length = sel_make_classes(); 523 if (length) { 524 pr_err("SELinux: failed to load policy classes\n"); 525 goto out1; 526 } 527 528 length = sel_make_policycap(); 529 if (length) { 530 pr_err("SELinux: failed to load policy capabilities\n"); 531 goto out1; 532 } 533 534 length = count; 535 536 out1: 537 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD, 538 "policy loaded auid=%u ses=%u", 539 from_kuid(&init_user_ns, audit_get_loginuid(current)), 540 audit_get_sessionid(current)); 541 out: 542 mutex_unlock(&sel_mutex); 543 vfree(data); 544 return length; 545 } 546 547 static const struct file_operations sel_load_ops = { 548 .write = sel_write_load, 549 .llseek = generic_file_llseek, 550 }; 551 552 static ssize_t sel_write_context(struct file *file, char *buf, size_t size) 553 { 554 char *canon = NULL; 555 u32 sid, len; 556 ssize_t length; 557 558 length = avc_has_perm(current_sid(), SECINITSID_SECURITY, 559 SECCLASS_SECURITY, SECURITY__CHECK_CONTEXT, NULL); 560 if (length) 561 goto out; 562 563 length = security_context_to_sid(buf, size, &sid, GFP_KERNEL); 564 if (length) 565 goto out; 566 567 length = security_sid_to_context(sid, &canon, &len); 568 if (length) 569 goto out; 570 571 length = -ERANGE; 572 if (len > SIMPLE_TRANSACTION_LIMIT) { 573 printk(KERN_ERR "SELinux: %s: context size (%u) exceeds " 574 "payload max\n", __func__, len); 575 goto out; 576 } 577 578 memcpy(buf, canon, len); 579 length = len; 580 out: 581 kfree(canon); 582 return length; 583 } 584 585 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf, 586 size_t count, loff_t *ppos) 587 { 588 char tmpbuf[TMPBUFLEN]; 589 ssize_t length; 590 591 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot); 592 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 593 } 594 595 static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf, 596 size_t count, loff_t *ppos) 597 { 598 char *page; 599 ssize_t length; 600 unsigned int new_value; 601 602 length = avc_has_perm(current_sid(), SECINITSID_SECURITY, 603 SECCLASS_SECURITY, SECURITY__SETCHECKREQPROT, 604 NULL); 605 if (length) 606 return length; 607 608 if (count >= PAGE_SIZE) 609 return -ENOMEM; 610 611 /* No partial writes. */ 612 if (*ppos != 0) 613 return -EINVAL; 614 615 page = memdup_user_nul(buf, count); 616 if (IS_ERR(page)) 617 return PTR_ERR(page); 618 619 length = -EINVAL; 620 if (sscanf(page, "%u", &new_value) != 1) 621 goto out; 622 623 selinux_checkreqprot = new_value ? 1 : 0; 624 length = count; 625 out: 626 kfree(page); 627 return length; 628 } 629 static const struct file_operations sel_checkreqprot_ops = { 630 .read = sel_read_checkreqprot, 631 .write = sel_write_checkreqprot, 632 .llseek = generic_file_llseek, 633 }; 634 635 static ssize_t sel_write_validatetrans(struct file *file, 636 const char __user *buf, 637 size_t count, loff_t *ppos) 638 { 639 char *oldcon = NULL, *newcon = NULL, *taskcon = NULL; 640 char *req = NULL; 641 u32 osid, nsid, tsid; 642 u16 tclass; 643 int rc; 644 645 rc = avc_has_perm(current_sid(), SECINITSID_SECURITY, 646 SECCLASS_SECURITY, SECURITY__VALIDATE_TRANS, NULL); 647 if (rc) 648 goto out; 649 650 rc = -ENOMEM; 651 if (count >= PAGE_SIZE) 652 goto out; 653 654 /* No partial writes. */ 655 rc = -EINVAL; 656 if (*ppos != 0) 657 goto out; 658 659 rc = -ENOMEM; 660 req = kzalloc(count + 1, GFP_KERNEL); 661 if (!req) 662 goto out; 663 664 rc = -EFAULT; 665 if (copy_from_user(req, buf, count)) 666 goto out; 667 668 rc = -ENOMEM; 669 oldcon = kzalloc(count + 1, GFP_KERNEL); 670 if (!oldcon) 671 goto out; 672 673 newcon = kzalloc(count + 1, GFP_KERNEL); 674 if (!newcon) 675 goto out; 676 677 taskcon = kzalloc(count + 1, GFP_KERNEL); 678 if (!taskcon) 679 goto out; 680 681 rc = -EINVAL; 682 if (sscanf(req, "%s %s %hu %s", oldcon, newcon, &tclass, taskcon) != 4) 683 goto out; 684 685 rc = security_context_str_to_sid(oldcon, &osid, GFP_KERNEL); 686 if (rc) 687 goto out; 688 689 rc = security_context_str_to_sid(newcon, &nsid, GFP_KERNEL); 690 if (rc) 691 goto out; 692 693 rc = security_context_str_to_sid(taskcon, &tsid, GFP_KERNEL); 694 if (rc) 695 goto out; 696 697 rc = security_validate_transition_user(osid, nsid, tsid, tclass); 698 if (!rc) 699 rc = count; 700 out: 701 kfree(req); 702 kfree(oldcon); 703 kfree(newcon); 704 kfree(taskcon); 705 return rc; 706 } 707 708 static const struct file_operations sel_transition_ops = { 709 .write = sel_write_validatetrans, 710 .llseek = generic_file_llseek, 711 }; 712 713 /* 714 * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c 715 */ 716 static ssize_t sel_write_access(struct file *file, char *buf, size_t size); 717 static ssize_t sel_write_create(struct file *file, char *buf, size_t size); 718 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size); 719 static ssize_t sel_write_user(struct file *file, char *buf, size_t size); 720 static ssize_t sel_write_member(struct file *file, char *buf, size_t size); 721 722 static ssize_t (*write_op[])(struct file *, char *, size_t) = { 723 [SEL_ACCESS] = sel_write_access, 724 [SEL_CREATE] = sel_write_create, 725 [SEL_RELABEL] = sel_write_relabel, 726 [SEL_USER] = sel_write_user, 727 [SEL_MEMBER] = sel_write_member, 728 [SEL_CONTEXT] = sel_write_context, 729 }; 730 731 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos) 732 { 733 ino_t ino = file_inode(file)->i_ino; 734 char *data; 735 ssize_t rv; 736 737 if (ino >= ARRAY_SIZE(write_op) || !write_op[ino]) 738 return -EINVAL; 739 740 data = simple_transaction_get(file, buf, size); 741 if (IS_ERR(data)) 742 return PTR_ERR(data); 743 744 rv = write_op[ino](file, data, size); 745 if (rv > 0) { 746 simple_transaction_set(file, rv); 747 rv = size; 748 } 749 return rv; 750 } 751 752 static const struct file_operations transaction_ops = { 753 .write = selinux_transaction_write, 754 .read = simple_transaction_read, 755 .release = simple_transaction_release, 756 .llseek = generic_file_llseek, 757 }; 758 759 /* 760 * payload - write methods 761 * If the method has a response, the response should be put in buf, 762 * and the length returned. Otherwise return 0 or and -error. 763 */ 764 765 static ssize_t sel_write_access(struct file *file, char *buf, size_t size) 766 { 767 char *scon = NULL, *tcon = NULL; 768 u32 ssid, tsid; 769 u16 tclass; 770 struct av_decision avd; 771 ssize_t length; 772 773 length = avc_has_perm(current_sid(), SECINITSID_SECURITY, 774 SECCLASS_SECURITY, SECURITY__COMPUTE_AV, NULL); 775 if (length) 776 goto out; 777 778 length = -ENOMEM; 779 scon = kzalloc(size + 1, GFP_KERNEL); 780 if (!scon) 781 goto out; 782 783 length = -ENOMEM; 784 tcon = kzalloc(size + 1, GFP_KERNEL); 785 if (!tcon) 786 goto out; 787 788 length = -EINVAL; 789 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3) 790 goto out; 791 792 length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL); 793 if (length) 794 goto out; 795 796 length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL); 797 if (length) 798 goto out; 799 800 security_compute_av_user(ssid, tsid, tclass, &avd); 801 802 length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, 803 "%x %x %x %x %u %x", 804 avd.allowed, 0xffffffff, 805 avd.auditallow, avd.auditdeny, 806 avd.seqno, avd.flags); 807 out: 808 kfree(tcon); 809 kfree(scon); 810 return length; 811 } 812 813 static ssize_t sel_write_create(struct file *file, char *buf, size_t size) 814 { 815 char *scon = NULL, *tcon = NULL; 816 char *namebuf = NULL, *objname = NULL; 817 u32 ssid, tsid, newsid; 818 u16 tclass; 819 ssize_t length; 820 char *newcon = NULL; 821 u32 len; 822 int nargs; 823 824 length = avc_has_perm(current_sid(), SECINITSID_SECURITY, 825 SECCLASS_SECURITY, SECURITY__COMPUTE_CREATE, 826 NULL); 827 if (length) 828 goto out; 829 830 length = -ENOMEM; 831 scon = kzalloc(size + 1, GFP_KERNEL); 832 if (!scon) 833 goto out; 834 835 length = -ENOMEM; 836 tcon = kzalloc(size + 1, GFP_KERNEL); 837 if (!tcon) 838 goto out; 839 840 length = -ENOMEM; 841 namebuf = kzalloc(size + 1, GFP_KERNEL); 842 if (!namebuf) 843 goto out; 844 845 length = -EINVAL; 846 nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf); 847 if (nargs < 3 || nargs > 4) 848 goto out; 849 if (nargs == 4) { 850 /* 851 * If and when the name of new object to be queried contains 852 * either whitespace or multibyte characters, they shall be 853 * encoded based on the percentage-encoding rule. 854 * If not encoded, the sscanf logic picks up only left-half 855 * of the supplied name; splitted by a whitespace unexpectedly. 856 */ 857 char *r, *w; 858 int c1, c2; 859 860 r = w = namebuf; 861 do { 862 c1 = *r++; 863 if (c1 == '+') 864 c1 = ' '; 865 else if (c1 == '%') { 866 c1 = hex_to_bin(*r++); 867 if (c1 < 0) 868 goto out; 869 c2 = hex_to_bin(*r++); 870 if (c2 < 0) 871 goto out; 872 c1 = (c1 << 4) | c2; 873 } 874 *w++ = c1; 875 } while (c1 != '\0'); 876 877 objname = namebuf; 878 } 879 880 length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL); 881 if (length) 882 goto out; 883 884 length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL); 885 if (length) 886 goto out; 887 888 length = security_transition_sid_user(ssid, tsid, tclass, 889 objname, &newsid); 890 if (length) 891 goto out; 892 893 length = security_sid_to_context(newsid, &newcon, &len); 894 if (length) 895 goto out; 896 897 length = -ERANGE; 898 if (len > SIMPLE_TRANSACTION_LIMIT) { 899 printk(KERN_ERR "SELinux: %s: context size (%u) exceeds " 900 "payload max\n", __func__, len); 901 goto out; 902 } 903 904 memcpy(buf, newcon, len); 905 length = len; 906 out: 907 kfree(newcon); 908 kfree(namebuf); 909 kfree(tcon); 910 kfree(scon); 911 return length; 912 } 913 914 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size) 915 { 916 char *scon = NULL, *tcon = NULL; 917 u32 ssid, tsid, newsid; 918 u16 tclass; 919 ssize_t length; 920 char *newcon = NULL; 921 u32 len; 922 923 length = avc_has_perm(current_sid(), SECINITSID_SECURITY, 924 SECCLASS_SECURITY, SECURITY__COMPUTE_RELABEL, 925 NULL); 926 if (length) 927 goto out; 928 929 length = -ENOMEM; 930 scon = kzalloc(size + 1, GFP_KERNEL); 931 if (!scon) 932 goto out; 933 934 length = -ENOMEM; 935 tcon = kzalloc(size + 1, GFP_KERNEL); 936 if (!tcon) 937 goto out; 938 939 length = -EINVAL; 940 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3) 941 goto out; 942 943 length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL); 944 if (length) 945 goto out; 946 947 length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL); 948 if (length) 949 goto out; 950 951 length = security_change_sid(ssid, tsid, tclass, &newsid); 952 if (length) 953 goto out; 954 955 length = security_sid_to_context(newsid, &newcon, &len); 956 if (length) 957 goto out; 958 959 length = -ERANGE; 960 if (len > SIMPLE_TRANSACTION_LIMIT) 961 goto out; 962 963 memcpy(buf, newcon, len); 964 length = len; 965 out: 966 kfree(newcon); 967 kfree(tcon); 968 kfree(scon); 969 return length; 970 } 971 972 static ssize_t sel_write_user(struct file *file, char *buf, size_t size) 973 { 974 char *con = NULL, *user = NULL, *ptr; 975 u32 sid, *sids = NULL; 976 ssize_t length; 977 char *newcon; 978 int i, rc; 979 u32 len, nsids; 980 981 length = avc_has_perm(current_sid(), SECINITSID_SECURITY, 982 SECCLASS_SECURITY, SECURITY__COMPUTE_USER, 983 NULL); 984 if (length) 985 goto out; 986 987 length = -ENOMEM; 988 con = kzalloc(size + 1, GFP_KERNEL); 989 if (!con) 990 goto out; 991 992 length = -ENOMEM; 993 user = kzalloc(size + 1, GFP_KERNEL); 994 if (!user) 995 goto out; 996 997 length = -EINVAL; 998 if (sscanf(buf, "%s %s", con, user) != 2) 999 goto out; 1000 1001 length = security_context_str_to_sid(con, &sid, GFP_KERNEL); 1002 if (length) 1003 goto out; 1004 1005 length = security_get_user_sids(sid, user, &sids, &nsids); 1006 if (length) 1007 goto out; 1008 1009 length = sprintf(buf, "%u", nsids) + 1; 1010 ptr = buf + length; 1011 for (i = 0; i < nsids; i++) { 1012 rc = security_sid_to_context(sids[i], &newcon, &len); 1013 if (rc) { 1014 length = rc; 1015 goto out; 1016 } 1017 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) { 1018 kfree(newcon); 1019 length = -ERANGE; 1020 goto out; 1021 } 1022 memcpy(ptr, newcon, len); 1023 kfree(newcon); 1024 ptr += len; 1025 length += len; 1026 } 1027 out: 1028 kfree(sids); 1029 kfree(user); 1030 kfree(con); 1031 return length; 1032 } 1033 1034 static ssize_t sel_write_member(struct file *file, char *buf, size_t size) 1035 { 1036 char *scon = NULL, *tcon = NULL; 1037 u32 ssid, tsid, newsid; 1038 u16 tclass; 1039 ssize_t length; 1040 char *newcon = NULL; 1041 u32 len; 1042 1043 length = avc_has_perm(current_sid(), SECINITSID_SECURITY, 1044 SECCLASS_SECURITY, SECURITY__COMPUTE_MEMBER, 1045 NULL); 1046 if (length) 1047 goto out; 1048 1049 length = -ENOMEM; 1050 scon = kzalloc(size + 1, GFP_KERNEL); 1051 if (!scon) 1052 goto out; 1053 1054 length = -ENOMEM; 1055 tcon = kzalloc(size + 1, GFP_KERNEL); 1056 if (!tcon) 1057 goto out; 1058 1059 length = -EINVAL; 1060 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3) 1061 goto out; 1062 1063 length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL); 1064 if (length) 1065 goto out; 1066 1067 length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL); 1068 if (length) 1069 goto out; 1070 1071 length = security_member_sid(ssid, tsid, tclass, &newsid); 1072 if (length) 1073 goto out; 1074 1075 length = security_sid_to_context(newsid, &newcon, &len); 1076 if (length) 1077 goto out; 1078 1079 length = -ERANGE; 1080 if (len > SIMPLE_TRANSACTION_LIMIT) { 1081 printk(KERN_ERR "SELinux: %s: context size (%u) exceeds " 1082 "payload max\n", __func__, len); 1083 goto out; 1084 } 1085 1086 memcpy(buf, newcon, len); 1087 length = len; 1088 out: 1089 kfree(newcon); 1090 kfree(tcon); 1091 kfree(scon); 1092 return length; 1093 } 1094 1095 static struct inode *sel_make_inode(struct super_block *sb, int mode) 1096 { 1097 struct inode *ret = new_inode(sb); 1098 1099 if (ret) { 1100 ret->i_mode = mode; 1101 ret->i_atime = ret->i_mtime = ret->i_ctime = current_time(ret); 1102 } 1103 return ret; 1104 } 1105 1106 static ssize_t sel_read_bool(struct file *filep, char __user *buf, 1107 size_t count, loff_t *ppos) 1108 { 1109 char *page = NULL; 1110 ssize_t length; 1111 ssize_t ret; 1112 int cur_enforcing; 1113 unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK; 1114 const char *name = filep->f_path.dentry->d_name.name; 1115 1116 mutex_lock(&sel_mutex); 1117 1118 ret = -EINVAL; 1119 if (index >= bool_num || strcmp(name, bool_pending_names[index])) 1120 goto out; 1121 1122 ret = -ENOMEM; 1123 page = (char *)get_zeroed_page(GFP_KERNEL); 1124 if (!page) 1125 goto out; 1126 1127 cur_enforcing = security_get_bool_value(index); 1128 if (cur_enforcing < 0) { 1129 ret = cur_enforcing; 1130 goto out; 1131 } 1132 length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing, 1133 bool_pending_values[index]); 1134 ret = simple_read_from_buffer(buf, count, ppos, page, length); 1135 out: 1136 mutex_unlock(&sel_mutex); 1137 free_page((unsigned long)page); 1138 return ret; 1139 } 1140 1141 static ssize_t sel_write_bool(struct file *filep, const char __user *buf, 1142 size_t count, loff_t *ppos) 1143 { 1144 char *page = NULL; 1145 ssize_t length; 1146 int new_value; 1147 unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK; 1148 const char *name = filep->f_path.dentry->d_name.name; 1149 1150 mutex_lock(&sel_mutex); 1151 1152 length = avc_has_perm(current_sid(), SECINITSID_SECURITY, 1153 SECCLASS_SECURITY, SECURITY__SETBOOL, 1154 NULL); 1155 if (length) 1156 goto out; 1157 1158 length = -EINVAL; 1159 if (index >= bool_num || strcmp(name, bool_pending_names[index])) 1160 goto out; 1161 1162 length = -ENOMEM; 1163 if (count >= PAGE_SIZE) 1164 goto out; 1165 1166 /* No partial writes. */ 1167 length = -EINVAL; 1168 if (*ppos != 0) 1169 goto out; 1170 1171 page = memdup_user_nul(buf, count); 1172 if (IS_ERR(page)) { 1173 length = PTR_ERR(page); 1174 page = NULL; 1175 goto out; 1176 } 1177 1178 length = -EINVAL; 1179 if (sscanf(page, "%d", &new_value) != 1) 1180 goto out; 1181 1182 if (new_value) 1183 new_value = 1; 1184 1185 bool_pending_values[index] = new_value; 1186 length = count; 1187 1188 out: 1189 mutex_unlock(&sel_mutex); 1190 kfree(page); 1191 return length; 1192 } 1193 1194 static const struct file_operations sel_bool_ops = { 1195 .read = sel_read_bool, 1196 .write = sel_write_bool, 1197 .llseek = generic_file_llseek, 1198 }; 1199 1200 static ssize_t sel_commit_bools_write(struct file *filep, 1201 const char __user *buf, 1202 size_t count, loff_t *ppos) 1203 { 1204 char *page = NULL; 1205 ssize_t length; 1206 int new_value; 1207 1208 mutex_lock(&sel_mutex); 1209 1210 length = avc_has_perm(current_sid(), SECINITSID_SECURITY, 1211 SECCLASS_SECURITY, SECURITY__SETBOOL, 1212 NULL); 1213 if (length) 1214 goto out; 1215 1216 length = -ENOMEM; 1217 if (count >= PAGE_SIZE) 1218 goto out; 1219 1220 /* No partial writes. */ 1221 length = -EINVAL; 1222 if (*ppos != 0) 1223 goto out; 1224 1225 page = memdup_user_nul(buf, count); 1226 if (IS_ERR(page)) { 1227 length = PTR_ERR(page); 1228 page = NULL; 1229 goto out; 1230 } 1231 1232 length = -EINVAL; 1233 if (sscanf(page, "%d", &new_value) != 1) 1234 goto out; 1235 1236 length = 0; 1237 if (new_value && bool_pending_values) 1238 length = security_set_bools(bool_num, bool_pending_values); 1239 1240 if (!length) 1241 length = count; 1242 1243 out: 1244 mutex_unlock(&sel_mutex); 1245 kfree(page); 1246 return length; 1247 } 1248 1249 static const struct file_operations sel_commit_bools_ops = { 1250 .write = sel_commit_bools_write, 1251 .llseek = generic_file_llseek, 1252 }; 1253 1254 static void sel_remove_entries(struct dentry *de) 1255 { 1256 d_genocide(de); 1257 shrink_dcache_parent(de); 1258 } 1259 1260 #define BOOL_DIR_NAME "booleans" 1261 1262 static int sel_make_bools(void) 1263 { 1264 int i, ret; 1265 ssize_t len; 1266 struct dentry *dentry = NULL; 1267 struct dentry *dir = bool_dir; 1268 struct inode *inode = NULL; 1269 struct inode_security_struct *isec; 1270 char **names = NULL, *page; 1271 int num; 1272 int *values = NULL; 1273 u32 sid; 1274 1275 /* remove any existing files */ 1276 for (i = 0; i < bool_num; i++) 1277 kfree(bool_pending_names[i]); 1278 kfree(bool_pending_names); 1279 kfree(bool_pending_values); 1280 bool_num = 0; 1281 bool_pending_names = NULL; 1282 bool_pending_values = NULL; 1283 1284 sel_remove_entries(dir); 1285 1286 ret = -ENOMEM; 1287 page = (char *)get_zeroed_page(GFP_KERNEL); 1288 if (!page) 1289 goto out; 1290 1291 ret = security_get_bools(&num, &names, &values); 1292 if (ret) 1293 goto out; 1294 1295 for (i = 0; i < num; i++) { 1296 ret = -ENOMEM; 1297 dentry = d_alloc_name(dir, names[i]); 1298 if (!dentry) 1299 goto out; 1300 1301 ret = -ENOMEM; 1302 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR); 1303 if (!inode) 1304 goto out; 1305 1306 ret = -ENAMETOOLONG; 1307 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]); 1308 if (len >= PAGE_SIZE) 1309 goto out; 1310 1311 isec = (struct inode_security_struct *)inode->i_security; 1312 ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid); 1313 if (ret) { 1314 pr_warn_ratelimited("SELinux: no sid found, defaulting to security isid for %s\n", 1315 page); 1316 sid = SECINITSID_SECURITY; 1317 } 1318 1319 isec->sid = sid; 1320 isec->initialized = LABEL_INITIALIZED; 1321 inode->i_fop = &sel_bool_ops; 1322 inode->i_ino = i|SEL_BOOL_INO_OFFSET; 1323 d_add(dentry, inode); 1324 } 1325 bool_num = num; 1326 bool_pending_names = names; 1327 bool_pending_values = values; 1328 1329 free_page((unsigned long)page); 1330 return 0; 1331 out: 1332 free_page((unsigned long)page); 1333 1334 if (names) { 1335 for (i = 0; i < num; i++) 1336 kfree(names[i]); 1337 kfree(names); 1338 } 1339 kfree(values); 1340 sel_remove_entries(dir); 1341 1342 return ret; 1343 } 1344 1345 #define NULL_FILE_NAME "null" 1346 1347 struct path selinux_null; 1348 1349 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf, 1350 size_t count, loff_t *ppos) 1351 { 1352 char tmpbuf[TMPBUFLEN]; 1353 ssize_t length; 1354 1355 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold); 1356 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1357 } 1358 1359 static ssize_t sel_write_avc_cache_threshold(struct file *file, 1360 const char __user *buf, 1361 size_t count, loff_t *ppos) 1362 1363 { 1364 char *page; 1365 ssize_t ret; 1366 unsigned int new_value; 1367 1368 ret = avc_has_perm(current_sid(), SECINITSID_SECURITY, 1369 SECCLASS_SECURITY, SECURITY__SETSECPARAM, 1370 NULL); 1371 if (ret) 1372 return ret; 1373 1374 if (count >= PAGE_SIZE) 1375 return -ENOMEM; 1376 1377 /* No partial writes. */ 1378 if (*ppos != 0) 1379 return -EINVAL; 1380 1381 page = memdup_user_nul(buf, count); 1382 if (IS_ERR(page)) 1383 return PTR_ERR(page); 1384 1385 ret = -EINVAL; 1386 if (sscanf(page, "%u", &new_value) != 1) 1387 goto out; 1388 1389 avc_cache_threshold = new_value; 1390 1391 ret = count; 1392 out: 1393 kfree(page); 1394 return ret; 1395 } 1396 1397 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf, 1398 size_t count, loff_t *ppos) 1399 { 1400 char *page; 1401 ssize_t length; 1402 1403 page = (char *)__get_free_page(GFP_KERNEL); 1404 if (!page) 1405 return -ENOMEM; 1406 1407 length = avc_get_hash_stats(page); 1408 if (length >= 0) 1409 length = simple_read_from_buffer(buf, count, ppos, page, length); 1410 free_page((unsigned long)page); 1411 1412 return length; 1413 } 1414 1415 static const struct file_operations sel_avc_cache_threshold_ops = { 1416 .read = sel_read_avc_cache_threshold, 1417 .write = sel_write_avc_cache_threshold, 1418 .llseek = generic_file_llseek, 1419 }; 1420 1421 static const struct file_operations sel_avc_hash_stats_ops = { 1422 .read = sel_read_avc_hash_stats, 1423 .llseek = generic_file_llseek, 1424 }; 1425 1426 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS 1427 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx) 1428 { 1429 int cpu; 1430 1431 for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) { 1432 if (!cpu_possible(cpu)) 1433 continue; 1434 *idx = cpu + 1; 1435 return &per_cpu(avc_cache_stats, cpu); 1436 } 1437 return NULL; 1438 } 1439 1440 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos) 1441 { 1442 loff_t n = *pos - 1; 1443 1444 if (*pos == 0) 1445 return SEQ_START_TOKEN; 1446 1447 return sel_avc_get_stat_idx(&n); 1448 } 1449 1450 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos) 1451 { 1452 return sel_avc_get_stat_idx(pos); 1453 } 1454 1455 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v) 1456 { 1457 struct avc_cache_stats *st = v; 1458 1459 if (v == SEQ_START_TOKEN) 1460 seq_printf(seq, "lookups hits misses allocations reclaims " 1461 "frees\n"); 1462 else { 1463 unsigned int lookups = st->lookups; 1464 unsigned int misses = st->misses; 1465 unsigned int hits = lookups - misses; 1466 seq_printf(seq, "%u %u %u %u %u %u\n", lookups, 1467 hits, misses, st->allocations, 1468 st->reclaims, st->frees); 1469 } 1470 return 0; 1471 } 1472 1473 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v) 1474 { } 1475 1476 static const struct seq_operations sel_avc_cache_stats_seq_ops = { 1477 .start = sel_avc_stats_seq_start, 1478 .next = sel_avc_stats_seq_next, 1479 .show = sel_avc_stats_seq_show, 1480 .stop = sel_avc_stats_seq_stop, 1481 }; 1482 1483 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file) 1484 { 1485 return seq_open(file, &sel_avc_cache_stats_seq_ops); 1486 } 1487 1488 static const struct file_operations sel_avc_cache_stats_ops = { 1489 .open = sel_open_avc_cache_stats, 1490 .read = seq_read, 1491 .llseek = seq_lseek, 1492 .release = seq_release, 1493 }; 1494 #endif 1495 1496 static int sel_make_avc_files(struct dentry *dir) 1497 { 1498 int i; 1499 static struct tree_descr files[] = { 1500 { "cache_threshold", 1501 &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR }, 1502 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO }, 1503 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS 1504 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO }, 1505 #endif 1506 }; 1507 1508 for (i = 0; i < ARRAY_SIZE(files); i++) { 1509 struct inode *inode; 1510 struct dentry *dentry; 1511 1512 dentry = d_alloc_name(dir, files[i].name); 1513 if (!dentry) 1514 return -ENOMEM; 1515 1516 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode); 1517 if (!inode) 1518 return -ENOMEM; 1519 1520 inode->i_fop = files[i].ops; 1521 inode->i_ino = ++sel_last_ino; 1522 d_add(dentry, inode); 1523 } 1524 1525 return 0; 1526 } 1527 1528 static ssize_t sel_read_initcon(struct file *file, char __user *buf, 1529 size_t count, loff_t *ppos) 1530 { 1531 char *con; 1532 u32 sid, len; 1533 ssize_t ret; 1534 1535 sid = file_inode(file)->i_ino&SEL_INO_MASK; 1536 ret = security_sid_to_context(sid, &con, &len); 1537 if (ret) 1538 return ret; 1539 1540 ret = simple_read_from_buffer(buf, count, ppos, con, len); 1541 kfree(con); 1542 return ret; 1543 } 1544 1545 static const struct file_operations sel_initcon_ops = { 1546 .read = sel_read_initcon, 1547 .llseek = generic_file_llseek, 1548 }; 1549 1550 static int sel_make_initcon_files(struct dentry *dir) 1551 { 1552 int i; 1553 1554 for (i = 1; i <= SECINITSID_NUM; i++) { 1555 struct inode *inode; 1556 struct dentry *dentry; 1557 dentry = d_alloc_name(dir, security_get_initial_sid_context(i)); 1558 if (!dentry) 1559 return -ENOMEM; 1560 1561 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO); 1562 if (!inode) 1563 return -ENOMEM; 1564 1565 inode->i_fop = &sel_initcon_ops; 1566 inode->i_ino = i|SEL_INITCON_INO_OFFSET; 1567 d_add(dentry, inode); 1568 } 1569 1570 return 0; 1571 } 1572 1573 static inline unsigned long sel_class_to_ino(u16 class) 1574 { 1575 return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET; 1576 } 1577 1578 static inline u16 sel_ino_to_class(unsigned long ino) 1579 { 1580 return (ino & SEL_INO_MASK) / (SEL_VEC_MAX + 1); 1581 } 1582 1583 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm) 1584 { 1585 return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET; 1586 } 1587 1588 static inline u32 sel_ino_to_perm(unsigned long ino) 1589 { 1590 return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1); 1591 } 1592 1593 static ssize_t sel_read_class(struct file *file, char __user *buf, 1594 size_t count, loff_t *ppos) 1595 { 1596 unsigned long ino = file_inode(file)->i_ino; 1597 char res[TMPBUFLEN]; 1598 ssize_t len = snprintf(res, sizeof(res), "%d", sel_ino_to_class(ino)); 1599 return simple_read_from_buffer(buf, count, ppos, res, len); 1600 } 1601 1602 static const struct file_operations sel_class_ops = { 1603 .read = sel_read_class, 1604 .llseek = generic_file_llseek, 1605 }; 1606 1607 static ssize_t sel_read_perm(struct file *file, char __user *buf, 1608 size_t count, loff_t *ppos) 1609 { 1610 unsigned long ino = file_inode(file)->i_ino; 1611 char res[TMPBUFLEN]; 1612 ssize_t len = snprintf(res, sizeof(res), "%d", sel_ino_to_perm(ino)); 1613 return simple_read_from_buffer(buf, count, ppos, res, len); 1614 } 1615 1616 static const struct file_operations sel_perm_ops = { 1617 .read = sel_read_perm, 1618 .llseek = generic_file_llseek, 1619 }; 1620 1621 static ssize_t sel_read_policycap(struct file *file, char __user *buf, 1622 size_t count, loff_t *ppos) 1623 { 1624 int value; 1625 char tmpbuf[TMPBUFLEN]; 1626 ssize_t length; 1627 unsigned long i_ino = file_inode(file)->i_ino; 1628 1629 value = security_policycap_supported(i_ino & SEL_INO_MASK); 1630 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value); 1631 1632 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1633 } 1634 1635 static const struct file_operations sel_policycap_ops = { 1636 .read = sel_read_policycap, 1637 .llseek = generic_file_llseek, 1638 }; 1639 1640 static int sel_make_perm_files(char *objclass, int classvalue, 1641 struct dentry *dir) 1642 { 1643 int i, rc, nperms; 1644 char **perms; 1645 1646 rc = security_get_permissions(objclass, &perms, &nperms); 1647 if (rc) 1648 return rc; 1649 1650 for (i = 0; i < nperms; i++) { 1651 struct inode *inode; 1652 struct dentry *dentry; 1653 1654 rc = -ENOMEM; 1655 dentry = d_alloc_name(dir, perms[i]); 1656 if (!dentry) 1657 goto out; 1658 1659 rc = -ENOMEM; 1660 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO); 1661 if (!inode) 1662 goto out; 1663 1664 inode->i_fop = &sel_perm_ops; 1665 /* i+1 since perm values are 1-indexed */ 1666 inode->i_ino = sel_perm_to_ino(classvalue, i + 1); 1667 d_add(dentry, inode); 1668 } 1669 rc = 0; 1670 out: 1671 for (i = 0; i < nperms; i++) 1672 kfree(perms[i]); 1673 kfree(perms); 1674 return rc; 1675 } 1676 1677 static int sel_make_class_dir_entries(char *classname, int index, 1678 struct dentry *dir) 1679 { 1680 struct dentry *dentry = NULL; 1681 struct inode *inode = NULL; 1682 int rc; 1683 1684 dentry = d_alloc_name(dir, "index"); 1685 if (!dentry) 1686 return -ENOMEM; 1687 1688 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO); 1689 if (!inode) 1690 return -ENOMEM; 1691 1692 inode->i_fop = &sel_class_ops; 1693 inode->i_ino = sel_class_to_ino(index); 1694 d_add(dentry, inode); 1695 1696 dentry = sel_make_dir(dir, "perms", &last_class_ino); 1697 if (IS_ERR(dentry)) 1698 return PTR_ERR(dentry); 1699 1700 rc = sel_make_perm_files(classname, index, dentry); 1701 1702 return rc; 1703 } 1704 1705 static int sel_make_classes(void) 1706 { 1707 int rc, nclasses, i; 1708 char **classes; 1709 1710 /* delete any existing entries */ 1711 sel_remove_entries(class_dir); 1712 1713 rc = security_get_classes(&classes, &nclasses); 1714 if (rc) 1715 return rc; 1716 1717 /* +2 since classes are 1-indexed */ 1718 last_class_ino = sel_class_to_ino(nclasses + 2); 1719 1720 for (i = 0; i < nclasses; i++) { 1721 struct dentry *class_name_dir; 1722 1723 class_name_dir = sel_make_dir(class_dir, classes[i], 1724 &last_class_ino); 1725 if (IS_ERR(class_name_dir)) { 1726 rc = PTR_ERR(class_name_dir); 1727 goto out; 1728 } 1729 1730 /* i+1 since class values are 1-indexed */ 1731 rc = sel_make_class_dir_entries(classes[i], i + 1, 1732 class_name_dir); 1733 if (rc) 1734 goto out; 1735 } 1736 rc = 0; 1737 out: 1738 for (i = 0; i < nclasses; i++) 1739 kfree(classes[i]); 1740 kfree(classes); 1741 return rc; 1742 } 1743 1744 static int sel_make_policycap(void) 1745 { 1746 unsigned int iter; 1747 struct dentry *dentry = NULL; 1748 struct inode *inode = NULL; 1749 1750 sel_remove_entries(policycap_dir); 1751 1752 for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) { 1753 if (iter < ARRAY_SIZE(policycap_names)) 1754 dentry = d_alloc_name(policycap_dir, 1755 policycap_names[iter]); 1756 else 1757 dentry = d_alloc_name(policycap_dir, "unknown"); 1758 1759 if (dentry == NULL) 1760 return -ENOMEM; 1761 1762 inode = sel_make_inode(policycap_dir->d_sb, S_IFREG | S_IRUGO); 1763 if (inode == NULL) 1764 return -ENOMEM; 1765 1766 inode->i_fop = &sel_policycap_ops; 1767 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET; 1768 d_add(dentry, inode); 1769 } 1770 1771 return 0; 1772 } 1773 1774 static struct dentry *sel_make_dir(struct dentry *dir, const char *name, 1775 unsigned long *ino) 1776 { 1777 struct dentry *dentry = d_alloc_name(dir, name); 1778 struct inode *inode; 1779 1780 if (!dentry) 1781 return ERR_PTR(-ENOMEM); 1782 1783 inode = sel_make_inode(dir->d_sb, S_IFDIR | S_IRUGO | S_IXUGO); 1784 if (!inode) { 1785 dput(dentry); 1786 return ERR_PTR(-ENOMEM); 1787 } 1788 1789 inode->i_op = &simple_dir_inode_operations; 1790 inode->i_fop = &simple_dir_operations; 1791 inode->i_ino = ++(*ino); 1792 /* directory inodes start off with i_nlink == 2 (for "." entry) */ 1793 inc_nlink(inode); 1794 d_add(dentry, inode); 1795 /* bump link count on parent directory, too */ 1796 inc_nlink(d_inode(dir)); 1797 1798 return dentry; 1799 } 1800 1801 static int sel_fill_super(struct super_block *sb, void *data, int silent) 1802 { 1803 int ret; 1804 struct dentry *dentry; 1805 struct inode *inode; 1806 struct inode_security_struct *isec; 1807 1808 static struct tree_descr selinux_files[] = { 1809 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR}, 1810 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR}, 1811 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO}, 1812 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO}, 1813 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO}, 1814 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO}, 1815 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO}, 1816 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO}, 1817 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR}, 1818 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO}, 1819 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR}, 1820 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO}, 1821 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR}, 1822 [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO}, 1823 [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO}, 1824 [SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO}, 1825 [SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUGO}, 1826 [SEL_VALIDATE_TRANS] = {"validatetrans", &sel_transition_ops, 1827 S_IWUGO}, 1828 /* last one */ {""} 1829 }; 1830 ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files); 1831 if (ret) 1832 goto err; 1833 1834 bool_dir = sel_make_dir(sb->s_root, BOOL_DIR_NAME, &sel_last_ino); 1835 if (IS_ERR(bool_dir)) { 1836 ret = PTR_ERR(bool_dir); 1837 bool_dir = NULL; 1838 goto err; 1839 } 1840 1841 ret = -ENOMEM; 1842 dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME); 1843 if (!dentry) 1844 goto err; 1845 1846 ret = -ENOMEM; 1847 inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO); 1848 if (!inode) 1849 goto err; 1850 1851 inode->i_ino = ++sel_last_ino; 1852 isec = (struct inode_security_struct *)inode->i_security; 1853 isec->sid = SECINITSID_DEVNULL; 1854 isec->sclass = SECCLASS_CHR_FILE; 1855 isec->initialized = LABEL_INITIALIZED; 1856 1857 init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3)); 1858 d_add(dentry, inode); 1859 selinux_null.dentry = dentry; 1860 1861 dentry = sel_make_dir(sb->s_root, "avc", &sel_last_ino); 1862 if (IS_ERR(dentry)) { 1863 ret = PTR_ERR(dentry); 1864 goto err; 1865 } 1866 1867 ret = sel_make_avc_files(dentry); 1868 if (ret) 1869 goto err; 1870 1871 dentry = sel_make_dir(sb->s_root, "initial_contexts", &sel_last_ino); 1872 if (IS_ERR(dentry)) { 1873 ret = PTR_ERR(dentry); 1874 goto err; 1875 } 1876 1877 ret = sel_make_initcon_files(dentry); 1878 if (ret) 1879 goto err; 1880 1881 class_dir = sel_make_dir(sb->s_root, "class", &sel_last_ino); 1882 if (IS_ERR(class_dir)) { 1883 ret = PTR_ERR(class_dir); 1884 class_dir = NULL; 1885 goto err; 1886 } 1887 1888 policycap_dir = sel_make_dir(sb->s_root, "policy_capabilities", &sel_last_ino); 1889 if (IS_ERR(policycap_dir)) { 1890 ret = PTR_ERR(policycap_dir); 1891 policycap_dir = NULL; 1892 goto err; 1893 } 1894 return 0; 1895 err: 1896 printk(KERN_ERR "SELinux: %s: failed while creating inodes\n", 1897 __func__); 1898 return ret; 1899 } 1900 1901 static struct dentry *sel_mount(struct file_system_type *fs_type, 1902 int flags, const char *dev_name, void *data) 1903 { 1904 return mount_single(fs_type, flags, data, sel_fill_super); 1905 } 1906 1907 static struct file_system_type sel_fs_type = { 1908 .name = "selinuxfs", 1909 .mount = sel_mount, 1910 .kill_sb = kill_litter_super, 1911 }; 1912 1913 struct vfsmount *selinuxfs_mount; 1914 1915 static int __init init_sel_fs(void) 1916 { 1917 int err; 1918 1919 if (!selinux_enabled) 1920 return 0; 1921 1922 err = sysfs_create_mount_point(fs_kobj, "selinux"); 1923 if (err) 1924 return err; 1925 1926 err = register_filesystem(&sel_fs_type); 1927 if (err) { 1928 sysfs_remove_mount_point(fs_kobj, "selinux"); 1929 return err; 1930 } 1931 1932 selinux_null.mnt = selinuxfs_mount = kern_mount(&sel_fs_type); 1933 if (IS_ERR(selinuxfs_mount)) { 1934 printk(KERN_ERR "selinuxfs: could not mount!\n"); 1935 err = PTR_ERR(selinuxfs_mount); 1936 selinuxfs_mount = NULL; 1937 } 1938 1939 return err; 1940 } 1941 1942 __initcall(init_sel_fs); 1943 1944 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 1945 void exit_sel_fs(void) 1946 { 1947 sysfs_remove_mount_point(fs_kobj, "selinux"); 1948 kern_unmount(selinuxfs_mount); 1949 unregister_filesystem(&sel_fs_type); 1950 } 1951 #endif 1952