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 }; 49 50 unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE; 51 52 static int __init checkreqprot_setup(char *str) 53 { 54 unsigned long checkreqprot; 55 if (!strict_strtoul(str, 0, &checkreqprot)) 56 selinux_checkreqprot = checkreqprot ? 1 : 0; 57 return 1; 58 } 59 __setup("checkreqprot=", checkreqprot_setup); 60 61 static DEFINE_MUTEX(sel_mutex); 62 63 /* global data for booleans */ 64 static struct dentry *bool_dir; 65 static int bool_num; 66 static char **bool_pending_names; 67 static int *bool_pending_values; 68 69 /* global data for classes */ 70 static struct dentry *class_dir; 71 static unsigned long last_class_ino; 72 73 static char policy_opened; 74 75 /* global data for policy capabilities */ 76 static struct dentry *policycap_dir; 77 78 extern void selnl_notify_setenforce(int val); 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 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 = filp->f_path.dentry->d_inode->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 extern int selinux_disable(void); 282 283 length = -ENOMEM; 284 if (count >= PAGE_SIZE) 285 goto out; 286 287 /* No partial writes. */ 288 length = -EINVAL; 289 if (*ppos != 0) 290 goto out; 291 292 length = -ENOMEM; 293 page = (char *)get_zeroed_page(GFP_KERNEL); 294 if (!page) 295 goto out; 296 297 length = -EFAULT; 298 if (copy_from_user(page, buf, count)) 299 goto out; 300 301 length = -EINVAL; 302 if (sscanf(page, "%d", &new_value) != 1) 303 goto out; 304 305 if (new_value) { 306 length = selinux_disable(); 307 if (length) 308 goto out; 309 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS, 310 "selinux=0 auid=%u ses=%u", 311 audit_get_loginuid(current), 312 audit_get_sessionid(current)); 313 } 314 315 length = count; 316 out: 317 free_page((unsigned long) page); 318 return length; 319 } 320 #else 321 #define sel_write_disable NULL 322 #endif 323 324 static const struct file_operations sel_disable_ops = { 325 .write = sel_write_disable, 326 .llseek = generic_file_llseek, 327 }; 328 329 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf, 330 size_t count, loff_t *ppos) 331 { 332 char tmpbuf[TMPBUFLEN]; 333 ssize_t length; 334 335 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX); 336 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 337 } 338 339 static const struct file_operations sel_policyvers_ops = { 340 .read = sel_read_policyvers, 341 .llseek = generic_file_llseek, 342 }; 343 344 /* declaration for sel_write_load */ 345 static int sel_make_bools(void); 346 static int sel_make_classes(void); 347 static int sel_make_policycap(void); 348 349 /* declaration for sel_make_class_dirs */ 350 static int sel_make_dir(struct inode *dir, struct dentry *dentry, 351 unsigned long *ino); 352 353 static ssize_t sel_read_mls(struct file *filp, char __user *buf, 354 size_t count, loff_t *ppos) 355 { 356 char tmpbuf[TMPBUFLEN]; 357 ssize_t length; 358 359 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", 360 security_mls_enabled()); 361 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 362 } 363 364 static const struct file_operations sel_mls_ops = { 365 .read = sel_read_mls, 366 .llseek = generic_file_llseek, 367 }; 368 369 struct policy_load_memory { 370 size_t len; 371 void *data; 372 }; 373 374 static int sel_open_policy(struct inode *inode, struct file *filp) 375 { 376 struct policy_load_memory *plm = NULL; 377 int rc; 378 379 BUG_ON(filp->private_data); 380 381 mutex_lock(&sel_mutex); 382 383 rc = task_has_security(current, SECURITY__READ_POLICY); 384 if (rc) 385 goto err; 386 387 rc = -EBUSY; 388 if (policy_opened) 389 goto err; 390 391 rc = -ENOMEM; 392 plm = kzalloc(sizeof(*plm), GFP_KERNEL); 393 if (!plm) 394 goto err; 395 396 if (i_size_read(inode) != security_policydb_len()) { 397 mutex_lock(&inode->i_mutex); 398 i_size_write(inode, security_policydb_len()); 399 mutex_unlock(&inode->i_mutex); 400 } 401 402 rc = security_read_policy(&plm->data, &plm->len); 403 if (rc) 404 goto err; 405 406 policy_opened = 1; 407 408 filp->private_data = plm; 409 410 mutex_unlock(&sel_mutex); 411 412 return 0; 413 err: 414 mutex_unlock(&sel_mutex); 415 416 if (plm) 417 vfree(plm->data); 418 kfree(plm); 419 return rc; 420 } 421 422 static int sel_release_policy(struct inode *inode, struct file *filp) 423 { 424 struct policy_load_memory *plm = filp->private_data; 425 426 BUG_ON(!plm); 427 428 policy_opened = 0; 429 430 vfree(plm->data); 431 kfree(plm); 432 433 return 0; 434 } 435 436 static ssize_t sel_read_policy(struct file *filp, char __user *buf, 437 size_t count, loff_t *ppos) 438 { 439 struct policy_load_memory *plm = filp->private_data; 440 int ret; 441 442 mutex_lock(&sel_mutex); 443 444 ret = task_has_security(current, SECURITY__READ_POLICY); 445 if (ret) 446 goto out; 447 448 ret = simple_read_from_buffer(buf, count, ppos, plm->data, plm->len); 449 out: 450 mutex_unlock(&sel_mutex); 451 return ret; 452 } 453 454 static int sel_mmap_policy_fault(struct vm_area_struct *vma, 455 struct vm_fault *vmf) 456 { 457 struct policy_load_memory *plm = vma->vm_file->private_data; 458 unsigned long offset; 459 struct page *page; 460 461 if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE)) 462 return VM_FAULT_SIGBUS; 463 464 offset = vmf->pgoff << PAGE_SHIFT; 465 if (offset >= roundup(plm->len, PAGE_SIZE)) 466 return VM_FAULT_SIGBUS; 467 468 page = vmalloc_to_page(plm->data + offset); 469 get_page(page); 470 471 vmf->page = page; 472 473 return 0; 474 } 475 476 static struct vm_operations_struct sel_mmap_policy_ops = { 477 .fault = sel_mmap_policy_fault, 478 .page_mkwrite = sel_mmap_policy_fault, 479 }; 480 481 int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma) 482 { 483 if (vma->vm_flags & VM_SHARED) { 484 /* do not allow mprotect to make mapping writable */ 485 vma->vm_flags &= ~VM_MAYWRITE; 486 487 if (vma->vm_flags & VM_WRITE) 488 return -EACCES; 489 } 490 491 vma->vm_flags |= VM_RESERVED; 492 vma->vm_ops = &sel_mmap_policy_ops; 493 494 return 0; 495 } 496 497 static const struct file_operations sel_policy_ops = { 498 .open = sel_open_policy, 499 .read = sel_read_policy, 500 .mmap = sel_mmap_policy, 501 .release = sel_release_policy, 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 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); 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->f_path.dentry->d_inode->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 if (length) 736 goto out; 737 738 length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid); 739 if (length) 740 goto out; 741 742 security_compute_av_user(ssid, tsid, tclass, &avd); 743 744 length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, 745 "%x %x %x %x %u %x", 746 avd.allowed, 0xffffffff, 747 avd.auditallow, avd.auditdeny, 748 avd.seqno, avd.flags); 749 out: 750 kfree(tcon); 751 kfree(scon); 752 return length; 753 } 754 755 static inline int hexcode_to_int(int code) { 756 if (code == '\0' || !isxdigit(code)) 757 return -1; 758 if (isdigit(code)) 759 return code - '0'; 760 return tolower(code) - 'a' + 10; 761 } 762 763 static ssize_t sel_write_create(struct file *file, char *buf, size_t size) 764 { 765 char *scon = NULL, *tcon = NULL; 766 char *namebuf = NULL, *objname = NULL; 767 u32 ssid, tsid, newsid; 768 u16 tclass; 769 ssize_t length; 770 char *newcon = NULL; 771 u32 len; 772 int nargs; 773 774 length = task_has_security(current, SECURITY__COMPUTE_CREATE); 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 = -ENOMEM; 789 namebuf = kzalloc(size + 1, GFP_KERNEL); 790 if (!namebuf) 791 goto out; 792 793 length = -EINVAL; 794 nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf); 795 if (nargs < 3 || nargs > 4) 796 goto out; 797 if (nargs == 4) { 798 /* 799 * If and when the name of new object to be queried contains 800 * either whitespace or multibyte characters, they shall be 801 * encoded based on the percentage-encoding rule. 802 * If not encoded, the sscanf logic picks up only left-half 803 * of the supplied name; splitted by a whitespace unexpectedly. 804 */ 805 char *r, *w; 806 int c1, c2; 807 808 r = w = namebuf; 809 do { 810 c1 = *r++; 811 if (c1 == '+') 812 c1 = ' '; 813 else if (c1 == '%') { 814 if ((c1 = hexcode_to_int(*r++)) < 0) 815 goto out; 816 if ((c2 = hexcode_to_int(*r++)) < 0) 817 goto out; 818 c1 = (c1 << 4) | c2; 819 } 820 *w++ = c1; 821 } while (c1 != '\0'); 822 823 objname = namebuf; 824 } 825 826 length = security_context_to_sid(scon, strlen(scon) + 1, &ssid); 827 if (length) 828 goto out; 829 830 length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid); 831 if (length) 832 goto out; 833 834 length = security_transition_sid_user(ssid, tsid, tclass, 835 objname, &newsid); 836 if (length) 837 goto out; 838 839 length = security_sid_to_context(newsid, &newcon, &len); 840 if (length) 841 goto out; 842 843 length = -ERANGE; 844 if (len > SIMPLE_TRANSACTION_LIMIT) { 845 printk(KERN_ERR "SELinux: %s: context size (%u) exceeds " 846 "payload max\n", __func__, len); 847 goto out; 848 } 849 850 memcpy(buf, newcon, len); 851 length = len; 852 out: 853 kfree(newcon); 854 kfree(namebuf); 855 kfree(tcon); 856 kfree(scon); 857 return length; 858 } 859 860 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size) 861 { 862 char *scon = NULL, *tcon = NULL; 863 u32 ssid, tsid, newsid; 864 u16 tclass; 865 ssize_t length; 866 char *newcon = NULL; 867 u32 len; 868 869 length = task_has_security(current, SECURITY__COMPUTE_RELABEL); 870 if (length) 871 goto out; 872 873 length = -ENOMEM; 874 scon = kzalloc(size + 1, GFP_KERNEL); 875 if (!scon) 876 goto out; 877 878 length = -ENOMEM; 879 tcon = kzalloc(size + 1, GFP_KERNEL); 880 if (!tcon) 881 goto out; 882 883 length = -EINVAL; 884 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3) 885 goto out; 886 887 length = security_context_to_sid(scon, strlen(scon) + 1, &ssid); 888 if (length) 889 goto out; 890 891 length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid); 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); 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 if (length) 1005 goto out; 1006 1007 length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid); 1008 if (length) 1009 goto out; 1010 1011 length = security_member_sid(ssid, tsid, tclass, &newsid); 1012 if (length) 1013 goto out; 1014 1015 length = security_sid_to_context(newsid, &newcon, &len); 1016 if (length) 1017 goto out; 1018 1019 length = -ERANGE; 1020 if (len > SIMPLE_TRANSACTION_LIMIT) { 1021 printk(KERN_ERR "SELinux: %s: context size (%u) exceeds " 1022 "payload max\n", __func__, len); 1023 goto out; 1024 } 1025 1026 memcpy(buf, newcon, len); 1027 length = len; 1028 out: 1029 kfree(newcon); 1030 kfree(tcon); 1031 kfree(scon); 1032 return length; 1033 } 1034 1035 static struct inode *sel_make_inode(struct super_block *sb, int mode) 1036 { 1037 struct inode *ret = new_inode(sb); 1038 1039 if (ret) { 1040 ret->i_mode = mode; 1041 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME; 1042 } 1043 return ret; 1044 } 1045 1046 static ssize_t sel_read_bool(struct file *filep, char __user *buf, 1047 size_t count, loff_t *ppos) 1048 { 1049 char *page = NULL; 1050 ssize_t length; 1051 ssize_t ret; 1052 int cur_enforcing; 1053 struct inode *inode = filep->f_path.dentry->d_inode; 1054 unsigned index = inode->i_ino & SEL_INO_MASK; 1055 const char *name = filep->f_path.dentry->d_name.name; 1056 1057 mutex_lock(&sel_mutex); 1058 1059 ret = -EINVAL; 1060 if (index >= bool_num || strcmp(name, bool_pending_names[index])) 1061 goto out; 1062 1063 ret = -ENOMEM; 1064 page = (char *)get_zeroed_page(GFP_KERNEL); 1065 if (!page) 1066 goto out; 1067 1068 cur_enforcing = security_get_bool_value(index); 1069 if (cur_enforcing < 0) { 1070 ret = cur_enforcing; 1071 goto out; 1072 } 1073 length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing, 1074 bool_pending_values[index]); 1075 ret = simple_read_from_buffer(buf, count, ppos, page, length); 1076 out: 1077 mutex_unlock(&sel_mutex); 1078 free_page((unsigned long)page); 1079 return ret; 1080 } 1081 1082 static ssize_t sel_write_bool(struct file *filep, const char __user *buf, 1083 size_t count, loff_t *ppos) 1084 { 1085 char *page = NULL; 1086 ssize_t length; 1087 int new_value; 1088 struct inode *inode = filep->f_path.dentry->d_inode; 1089 unsigned index = inode->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_u.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_pending_names = NULL; 1245 bool_pending_values = NULL; 1246 1247 sel_remove_entries(dir); 1248 1249 ret = -ENOMEM; 1250 page = (char *)get_zeroed_page(GFP_KERNEL); 1251 if (!page) 1252 goto out; 1253 1254 ret = security_get_bools(&num, &names, &values); 1255 if (ret) 1256 goto out; 1257 1258 for (i = 0; i < num; i++) { 1259 ret = -ENOMEM; 1260 dentry = d_alloc_name(dir, names[i]); 1261 if (!dentry) 1262 goto out; 1263 1264 ret = -ENOMEM; 1265 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR); 1266 if (!inode) 1267 goto out; 1268 1269 ret = -EINVAL; 1270 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]); 1271 if (len < 0) 1272 goto out; 1273 1274 ret = -ENAMETOOLONG; 1275 if (len >= PAGE_SIZE) 1276 goto out; 1277 1278 isec = (struct inode_security_struct *)inode->i_security; 1279 ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid); 1280 if (ret) 1281 goto out; 1282 1283 isec->sid = sid; 1284 isec->initialized = 1; 1285 inode->i_fop = &sel_bool_ops; 1286 inode->i_ino = i|SEL_BOOL_INO_OFFSET; 1287 d_add(dentry, inode); 1288 } 1289 bool_num = num; 1290 bool_pending_names = names; 1291 bool_pending_values = values; 1292 1293 free_page((unsigned long)page); 1294 return 0; 1295 out: 1296 free_page((unsigned long)page); 1297 1298 if (names) { 1299 for (i = 0; i < num; i++) 1300 kfree(names[i]); 1301 kfree(names); 1302 } 1303 kfree(values); 1304 sel_remove_entries(dir); 1305 1306 return ret; 1307 } 1308 1309 #define NULL_FILE_NAME "null" 1310 1311 struct dentry *selinux_null; 1312 1313 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf, 1314 size_t count, loff_t *ppos) 1315 { 1316 char tmpbuf[TMPBUFLEN]; 1317 ssize_t length; 1318 1319 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold); 1320 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1321 } 1322 1323 static ssize_t sel_write_avc_cache_threshold(struct file *file, 1324 const char __user *buf, 1325 size_t count, loff_t *ppos) 1326 1327 { 1328 char *page = NULL; 1329 ssize_t ret; 1330 int new_value; 1331 1332 ret = task_has_security(current, SECURITY__SETSECPARAM); 1333 if (ret) 1334 goto out; 1335 1336 ret = -ENOMEM; 1337 if (count >= PAGE_SIZE) 1338 goto out; 1339 1340 /* No partial writes. */ 1341 ret = -EINVAL; 1342 if (*ppos != 0) 1343 goto out; 1344 1345 ret = -ENOMEM; 1346 page = (char *)get_zeroed_page(GFP_KERNEL); 1347 if (!page) 1348 goto out; 1349 1350 ret = -EFAULT; 1351 if (copy_from_user(page, buf, count)) 1352 goto out; 1353 1354 ret = -EINVAL; 1355 if (sscanf(page, "%u", &new_value) != 1) 1356 goto out; 1357 1358 avc_cache_threshold = new_value; 1359 1360 ret = count; 1361 out: 1362 free_page((unsigned long)page); 1363 return ret; 1364 } 1365 1366 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf, 1367 size_t count, loff_t *ppos) 1368 { 1369 char *page; 1370 ssize_t length; 1371 1372 page = (char *)__get_free_page(GFP_KERNEL); 1373 if (!page) 1374 return -ENOMEM; 1375 1376 length = avc_get_hash_stats(page); 1377 if (length >= 0) 1378 length = simple_read_from_buffer(buf, count, ppos, page, length); 1379 free_page((unsigned long)page); 1380 1381 return length; 1382 } 1383 1384 static const struct file_operations sel_avc_cache_threshold_ops = { 1385 .read = sel_read_avc_cache_threshold, 1386 .write = sel_write_avc_cache_threshold, 1387 .llseek = generic_file_llseek, 1388 }; 1389 1390 static const struct file_operations sel_avc_hash_stats_ops = { 1391 .read = sel_read_avc_hash_stats, 1392 .llseek = generic_file_llseek, 1393 }; 1394 1395 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS 1396 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx) 1397 { 1398 int cpu; 1399 1400 for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) { 1401 if (!cpu_possible(cpu)) 1402 continue; 1403 *idx = cpu + 1; 1404 return &per_cpu(avc_cache_stats, cpu); 1405 } 1406 return NULL; 1407 } 1408 1409 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos) 1410 { 1411 loff_t n = *pos - 1; 1412 1413 if (*pos == 0) 1414 return SEQ_START_TOKEN; 1415 1416 return sel_avc_get_stat_idx(&n); 1417 } 1418 1419 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos) 1420 { 1421 return sel_avc_get_stat_idx(pos); 1422 } 1423 1424 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v) 1425 { 1426 struct avc_cache_stats *st = v; 1427 1428 if (v == SEQ_START_TOKEN) 1429 seq_printf(seq, "lookups hits misses allocations reclaims " 1430 "frees\n"); 1431 else { 1432 unsigned int lookups = st->lookups; 1433 unsigned int misses = st->misses; 1434 unsigned int hits = lookups - misses; 1435 seq_printf(seq, "%u %u %u %u %u %u\n", lookups, 1436 hits, misses, st->allocations, 1437 st->reclaims, st->frees); 1438 } 1439 return 0; 1440 } 1441 1442 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v) 1443 { } 1444 1445 static const struct seq_operations sel_avc_cache_stats_seq_ops = { 1446 .start = sel_avc_stats_seq_start, 1447 .next = sel_avc_stats_seq_next, 1448 .show = sel_avc_stats_seq_show, 1449 .stop = sel_avc_stats_seq_stop, 1450 }; 1451 1452 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file) 1453 { 1454 return seq_open(file, &sel_avc_cache_stats_seq_ops); 1455 } 1456 1457 static const struct file_operations sel_avc_cache_stats_ops = { 1458 .open = sel_open_avc_cache_stats, 1459 .read = seq_read, 1460 .llseek = seq_lseek, 1461 .release = seq_release, 1462 }; 1463 #endif 1464 1465 static int sel_make_avc_files(struct dentry *dir) 1466 { 1467 int i; 1468 static struct tree_descr files[] = { 1469 { "cache_threshold", 1470 &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR }, 1471 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO }, 1472 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS 1473 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO }, 1474 #endif 1475 }; 1476 1477 for (i = 0; i < ARRAY_SIZE(files); i++) { 1478 struct inode *inode; 1479 struct dentry *dentry; 1480 1481 dentry = d_alloc_name(dir, files[i].name); 1482 if (!dentry) 1483 return -ENOMEM; 1484 1485 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode); 1486 if (!inode) 1487 return -ENOMEM; 1488 1489 inode->i_fop = files[i].ops; 1490 inode->i_ino = ++sel_last_ino; 1491 d_add(dentry, inode); 1492 } 1493 1494 return 0; 1495 } 1496 1497 static ssize_t sel_read_initcon(struct file *file, char __user *buf, 1498 size_t count, loff_t *ppos) 1499 { 1500 struct inode *inode; 1501 char *con; 1502 u32 sid, len; 1503 ssize_t ret; 1504 1505 inode = file->f_path.dentry->d_inode; 1506 sid = inode->i_ino&SEL_INO_MASK; 1507 ret = security_sid_to_context(sid, &con, &len); 1508 if (ret) 1509 return ret; 1510 1511 ret = simple_read_from_buffer(buf, count, ppos, con, len); 1512 kfree(con); 1513 return ret; 1514 } 1515 1516 static const struct file_operations sel_initcon_ops = { 1517 .read = sel_read_initcon, 1518 .llseek = generic_file_llseek, 1519 }; 1520 1521 static int sel_make_initcon_files(struct dentry *dir) 1522 { 1523 int i; 1524 1525 for (i = 1; i <= SECINITSID_NUM; i++) { 1526 struct inode *inode; 1527 struct dentry *dentry; 1528 dentry = d_alloc_name(dir, security_get_initial_sid_context(i)); 1529 if (!dentry) 1530 return -ENOMEM; 1531 1532 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO); 1533 if (!inode) 1534 return -ENOMEM; 1535 1536 inode->i_fop = &sel_initcon_ops; 1537 inode->i_ino = i|SEL_INITCON_INO_OFFSET; 1538 d_add(dentry, inode); 1539 } 1540 1541 return 0; 1542 } 1543 1544 static inline unsigned int sel_div(unsigned long a, unsigned long b) 1545 { 1546 return a / b - (a % b < 0); 1547 } 1548 1549 static inline unsigned long sel_class_to_ino(u16 class) 1550 { 1551 return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET; 1552 } 1553 1554 static inline u16 sel_ino_to_class(unsigned long ino) 1555 { 1556 return sel_div(ino & SEL_INO_MASK, SEL_VEC_MAX + 1); 1557 } 1558 1559 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm) 1560 { 1561 return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET; 1562 } 1563 1564 static inline u32 sel_ino_to_perm(unsigned long ino) 1565 { 1566 return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1); 1567 } 1568 1569 static ssize_t sel_read_class(struct file *file, char __user *buf, 1570 size_t count, loff_t *ppos) 1571 { 1572 ssize_t rc, len; 1573 char *page; 1574 unsigned long ino = file->f_path.dentry->d_inode->i_ino; 1575 1576 page = (char *)__get_free_page(GFP_KERNEL); 1577 if (!page) 1578 return -ENOMEM; 1579 1580 len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_class(ino)); 1581 rc = simple_read_from_buffer(buf, count, ppos, page, len); 1582 free_page((unsigned long)page); 1583 1584 return rc; 1585 } 1586 1587 static const struct file_operations sel_class_ops = { 1588 .read = sel_read_class, 1589 .llseek = generic_file_llseek, 1590 }; 1591 1592 static ssize_t sel_read_perm(struct file *file, char __user *buf, 1593 size_t count, loff_t *ppos) 1594 { 1595 ssize_t rc, len; 1596 char *page; 1597 unsigned long ino = file->f_path.dentry->d_inode->i_ino; 1598 1599 page = (char *)__get_free_page(GFP_KERNEL); 1600 if (!page) 1601 return -ENOMEM; 1602 1603 len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_perm(ino)); 1604 rc = simple_read_from_buffer(buf, count, ppos, page, len); 1605 free_page((unsigned long)page); 1606 1607 return rc; 1608 } 1609 1610 static const struct file_operations sel_perm_ops = { 1611 .read = sel_read_perm, 1612 .llseek = generic_file_llseek, 1613 }; 1614 1615 static ssize_t sel_read_policycap(struct file *file, char __user *buf, 1616 size_t count, loff_t *ppos) 1617 { 1618 int value; 1619 char tmpbuf[TMPBUFLEN]; 1620 ssize_t length; 1621 unsigned long i_ino = file->f_path.dentry->d_inode->i_ino; 1622 1623 value = security_policycap_supported(i_ino & SEL_INO_MASK); 1624 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value); 1625 1626 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1627 } 1628 1629 static const struct file_operations sel_policycap_ops = { 1630 .read = sel_read_policycap, 1631 .llseek = generic_file_llseek, 1632 }; 1633 1634 static int sel_make_perm_files(char *objclass, int classvalue, 1635 struct dentry *dir) 1636 { 1637 int i, rc, nperms; 1638 char **perms; 1639 1640 rc = security_get_permissions(objclass, &perms, &nperms); 1641 if (rc) 1642 return rc; 1643 1644 for (i = 0; i < nperms; i++) { 1645 struct inode *inode; 1646 struct dentry *dentry; 1647 1648 rc = -ENOMEM; 1649 dentry = d_alloc_name(dir, perms[i]); 1650 if (!dentry) 1651 goto out; 1652 1653 rc = -ENOMEM; 1654 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO); 1655 if (!inode) 1656 goto out; 1657 1658 inode->i_fop = &sel_perm_ops; 1659 /* i+1 since perm values are 1-indexed */ 1660 inode->i_ino = sel_perm_to_ino(classvalue, i + 1); 1661 d_add(dentry, inode); 1662 } 1663 rc = 0; 1664 out: 1665 for (i = 0; i < nperms; i++) 1666 kfree(perms[i]); 1667 kfree(perms); 1668 return rc; 1669 } 1670 1671 static int sel_make_class_dir_entries(char *classname, int index, 1672 struct dentry *dir) 1673 { 1674 struct dentry *dentry = NULL; 1675 struct inode *inode = NULL; 1676 int rc; 1677 1678 dentry = d_alloc_name(dir, "index"); 1679 if (!dentry) 1680 return -ENOMEM; 1681 1682 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO); 1683 if (!inode) 1684 return -ENOMEM; 1685 1686 inode->i_fop = &sel_class_ops; 1687 inode->i_ino = sel_class_to_ino(index); 1688 d_add(dentry, inode); 1689 1690 dentry = d_alloc_name(dir, "perms"); 1691 if (!dentry) 1692 return -ENOMEM; 1693 1694 rc = sel_make_dir(dir->d_inode, dentry, &last_class_ino); 1695 if (rc) 1696 return rc; 1697 1698 rc = sel_make_perm_files(classname, index, dentry); 1699 1700 return rc; 1701 } 1702 1703 static void sel_remove_classes(void) 1704 { 1705 struct list_head *class_node; 1706 1707 list_for_each(class_node, &class_dir->d_subdirs) { 1708 struct dentry *class_subdir = list_entry(class_node, 1709 struct dentry, d_u.d_child); 1710 struct list_head *class_subdir_node; 1711 1712 list_for_each(class_subdir_node, &class_subdir->d_subdirs) { 1713 struct dentry *d = list_entry(class_subdir_node, 1714 struct dentry, d_u.d_child); 1715 1716 if (d->d_inode) 1717 if (d->d_inode->i_mode & S_IFDIR) 1718 sel_remove_entries(d); 1719 } 1720 1721 sel_remove_entries(class_subdir); 1722 } 1723 1724 sel_remove_entries(class_dir); 1725 } 1726 1727 static int sel_make_classes(void) 1728 { 1729 int rc, nclasses, i; 1730 char **classes; 1731 1732 /* delete any existing entries */ 1733 sel_remove_classes(); 1734 1735 rc = security_get_classes(&classes, &nclasses); 1736 if (rc) 1737 return rc; 1738 1739 /* +2 since classes are 1-indexed */ 1740 last_class_ino = sel_class_to_ino(nclasses + 2); 1741 1742 for (i = 0; i < nclasses; i++) { 1743 struct dentry *class_name_dir; 1744 1745 rc = -ENOMEM; 1746 class_name_dir = d_alloc_name(class_dir, classes[i]); 1747 if (!class_name_dir) 1748 goto out; 1749 1750 rc = sel_make_dir(class_dir->d_inode, class_name_dir, 1751 &last_class_ino); 1752 if (rc) 1753 goto out; 1754 1755 /* i+1 since class values are 1-indexed */ 1756 rc = sel_make_class_dir_entries(classes[i], i + 1, 1757 class_name_dir); 1758 if (rc) 1759 goto out; 1760 } 1761 rc = 0; 1762 out: 1763 for (i = 0; i < nclasses; i++) 1764 kfree(classes[i]); 1765 kfree(classes); 1766 return rc; 1767 } 1768 1769 static int sel_make_policycap(void) 1770 { 1771 unsigned int iter; 1772 struct dentry *dentry = NULL; 1773 struct inode *inode = NULL; 1774 1775 sel_remove_entries(policycap_dir); 1776 1777 for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) { 1778 if (iter < ARRAY_SIZE(policycap_names)) 1779 dentry = d_alloc_name(policycap_dir, 1780 policycap_names[iter]); 1781 else 1782 dentry = d_alloc_name(policycap_dir, "unknown"); 1783 1784 if (dentry == NULL) 1785 return -ENOMEM; 1786 1787 inode = sel_make_inode(policycap_dir->d_sb, S_IFREG | S_IRUGO); 1788 if (inode == NULL) 1789 return -ENOMEM; 1790 1791 inode->i_fop = &sel_policycap_ops; 1792 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET; 1793 d_add(dentry, inode); 1794 } 1795 1796 return 0; 1797 } 1798 1799 static int sel_make_dir(struct inode *dir, struct dentry *dentry, 1800 unsigned long *ino) 1801 { 1802 struct inode *inode; 1803 1804 inode = sel_make_inode(dir->i_sb, S_IFDIR | S_IRUGO | S_IXUGO); 1805 if (!inode) 1806 return -ENOMEM; 1807 1808 inode->i_op = &simple_dir_inode_operations; 1809 inode->i_fop = &simple_dir_operations; 1810 inode->i_ino = ++(*ino); 1811 /* directory inodes start off with i_nlink == 2 (for "." entry) */ 1812 inc_nlink(inode); 1813 d_add(dentry, inode); 1814 /* bump link count on parent directory, too */ 1815 inc_nlink(dir); 1816 1817 return 0; 1818 } 1819 1820 static int sel_fill_super(struct super_block *sb, void *data, int silent) 1821 { 1822 int ret; 1823 struct dentry *dentry; 1824 struct inode *inode, *root_inode; 1825 struct inode_security_struct *isec; 1826 1827 static struct tree_descr selinux_files[] = { 1828 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR}, 1829 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR}, 1830 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO}, 1831 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO}, 1832 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO}, 1833 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO}, 1834 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO}, 1835 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO}, 1836 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR}, 1837 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO}, 1838 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR}, 1839 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO}, 1840 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR}, 1841 [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO}, 1842 [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO}, 1843 [SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO}, 1844 [SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUSR}, 1845 /* last one */ {""} 1846 }; 1847 ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files); 1848 if (ret) 1849 goto err; 1850 1851 root_inode = sb->s_root->d_inode; 1852 1853 ret = -ENOMEM; 1854 dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME); 1855 if (!dentry) 1856 goto err; 1857 1858 ret = sel_make_dir(root_inode, dentry, &sel_last_ino); 1859 if (ret) 1860 goto err; 1861 1862 bool_dir = dentry; 1863 1864 ret = -ENOMEM; 1865 dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME); 1866 if (!dentry) 1867 goto err; 1868 1869 ret = -ENOMEM; 1870 inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO); 1871 if (!inode) 1872 goto err; 1873 1874 inode->i_ino = ++sel_last_ino; 1875 isec = (struct inode_security_struct *)inode->i_security; 1876 isec->sid = SECINITSID_DEVNULL; 1877 isec->sclass = SECCLASS_CHR_FILE; 1878 isec->initialized = 1; 1879 1880 init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3)); 1881 d_add(dentry, inode); 1882 selinux_null = dentry; 1883 1884 ret = -ENOMEM; 1885 dentry = d_alloc_name(sb->s_root, "avc"); 1886 if (!dentry) 1887 goto err; 1888 1889 ret = sel_make_dir(root_inode, dentry, &sel_last_ino); 1890 if (ret) 1891 goto err; 1892 1893 ret = sel_make_avc_files(dentry); 1894 if (ret) 1895 goto err; 1896 1897 ret = -ENOMEM; 1898 dentry = d_alloc_name(sb->s_root, "initial_contexts"); 1899 if (!dentry) 1900 goto err; 1901 1902 ret = sel_make_dir(root_inode, dentry, &sel_last_ino); 1903 if (ret) 1904 goto err; 1905 1906 ret = sel_make_initcon_files(dentry); 1907 if (ret) 1908 goto err; 1909 1910 ret = -ENOMEM; 1911 dentry = d_alloc_name(sb->s_root, "class"); 1912 if (!dentry) 1913 goto err; 1914 1915 ret = sel_make_dir(root_inode, dentry, &sel_last_ino); 1916 if (ret) 1917 goto err; 1918 1919 class_dir = dentry; 1920 1921 ret = -ENOMEM; 1922 dentry = d_alloc_name(sb->s_root, "policy_capabilities"); 1923 if (!dentry) 1924 goto err; 1925 1926 ret = sel_make_dir(root_inode, dentry, &sel_last_ino); 1927 if (ret) 1928 goto err; 1929 1930 policycap_dir = dentry; 1931 1932 return 0; 1933 err: 1934 printk(KERN_ERR "SELinux: %s: failed while creating inodes\n", 1935 __func__); 1936 return ret; 1937 } 1938 1939 static struct dentry *sel_mount(struct file_system_type *fs_type, 1940 int flags, const char *dev_name, void *data) 1941 { 1942 return mount_single(fs_type, flags, data, sel_fill_super); 1943 } 1944 1945 static struct file_system_type sel_fs_type = { 1946 .name = "selinuxfs", 1947 .mount = sel_mount, 1948 .kill_sb = kill_litter_super, 1949 }; 1950 1951 struct vfsmount *selinuxfs_mount; 1952 static struct kobject *selinuxfs_kobj; 1953 1954 static int __init init_sel_fs(void) 1955 { 1956 int err; 1957 1958 if (!selinux_enabled) 1959 return 0; 1960 1961 selinuxfs_kobj = kobject_create_and_add("selinux", fs_kobj); 1962 if (!selinuxfs_kobj) 1963 return -ENOMEM; 1964 1965 err = register_filesystem(&sel_fs_type); 1966 if (err) { 1967 kobject_put(selinuxfs_kobj); 1968 return err; 1969 } 1970 1971 selinuxfs_mount = kern_mount(&sel_fs_type); 1972 if (IS_ERR(selinuxfs_mount)) { 1973 printk(KERN_ERR "selinuxfs: could not mount!\n"); 1974 err = PTR_ERR(selinuxfs_mount); 1975 selinuxfs_mount = NULL; 1976 } 1977 1978 return err; 1979 } 1980 1981 __initcall(init_sel_fs); 1982 1983 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 1984 void exit_sel_fs(void) 1985 { 1986 kobject_put(selinuxfs_kobj); 1987 kern_unmount(selinuxfs_mount); 1988 unregister_filesystem(&sel_fs_type); 1989 } 1990 #endif 1991