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