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 /* Check whether a task is allowed to use a security operation. */ 79 static int task_has_security(struct task_struct *tsk, 80 u32 perms) 81 { 82 const struct task_security_struct *tsec; 83 u32 sid = 0; 84 85 rcu_read_lock(); 86 tsec = __task_cred(tsk)->security; 87 if (tsec) 88 sid = tsec->sid; 89 rcu_read_unlock(); 90 if (!tsec) 91 return -EACCES; 92 93 return avc_has_perm(sid, SECINITSID_SECURITY, 94 SECCLASS_SECURITY, perms, NULL); 95 } 96 97 enum sel_inos { 98 SEL_ROOT_INO = 2, 99 SEL_LOAD, /* load policy */ 100 SEL_ENFORCE, /* get or set enforcing status */ 101 SEL_CONTEXT, /* validate context */ 102 SEL_ACCESS, /* compute access decision */ 103 SEL_CREATE, /* compute create labeling decision */ 104 SEL_RELABEL, /* compute relabeling decision */ 105 SEL_USER, /* compute reachable user contexts */ 106 SEL_POLICYVERS, /* return policy version for this kernel */ 107 SEL_COMMIT_BOOLS, /* commit new boolean values */ 108 SEL_MLS, /* return if MLS policy is enabled */ 109 SEL_DISABLE, /* disable SELinux until next reboot */ 110 SEL_MEMBER, /* compute polyinstantiation membership decision */ 111 SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */ 112 SEL_COMPAT_NET, /* whether to use old compat network packet controls */ 113 SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */ 114 SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */ 115 SEL_STATUS, /* export current status using mmap() */ 116 SEL_POLICY, /* allow userspace to read the in kernel policy */ 117 SEL_INO_NEXT, /* The next inode number to use */ 118 }; 119 120 static unsigned long sel_last_ino = SEL_INO_NEXT - 1; 121 122 #define SEL_INITCON_INO_OFFSET 0x01000000 123 #define SEL_BOOL_INO_OFFSET 0x02000000 124 #define SEL_CLASS_INO_OFFSET 0x04000000 125 #define SEL_POLICYCAP_INO_OFFSET 0x08000000 126 #define SEL_INO_MASK 0x00ffffff 127 128 #define TMPBUFLEN 12 129 static ssize_t sel_read_enforce(struct file *filp, char __user *buf, 130 size_t count, loff_t *ppos) 131 { 132 char tmpbuf[TMPBUFLEN]; 133 ssize_t length; 134 135 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing); 136 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 137 } 138 139 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 140 static ssize_t sel_write_enforce(struct file *file, const char __user *buf, 141 size_t count, loff_t *ppos) 142 143 { 144 char *page = NULL; 145 ssize_t length; 146 int new_value; 147 148 length = -ENOMEM; 149 if (count >= PAGE_SIZE) 150 goto out; 151 152 /* No partial writes. */ 153 length = EINVAL; 154 if (*ppos != 0) 155 goto out; 156 157 length = -ENOMEM; 158 page = (char *)get_zeroed_page(GFP_KERNEL); 159 if (!page) 160 goto out; 161 162 length = -EFAULT; 163 if (copy_from_user(page, buf, count)) 164 goto out; 165 166 length = -EINVAL; 167 if (sscanf(page, "%d", &new_value) != 1) 168 goto out; 169 170 if (new_value != selinux_enforcing) { 171 length = task_has_security(current, SECURITY__SETENFORCE); 172 if (length) 173 goto out; 174 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS, 175 "enforcing=%d old_enforcing=%d auid=%u ses=%u", 176 new_value, selinux_enforcing, 177 audit_get_loginuid(current), 178 audit_get_sessionid(current)); 179 selinux_enforcing = new_value; 180 if (selinux_enforcing) 181 avc_ss_reset(0); 182 selnl_notify_setenforce(selinux_enforcing); 183 selinux_status_update_setenforce(selinux_enforcing); 184 } 185 length = count; 186 out: 187 free_page((unsigned long) page); 188 return length; 189 } 190 #else 191 #define sel_write_enforce NULL 192 #endif 193 194 static const struct file_operations sel_enforce_ops = { 195 .read = sel_read_enforce, 196 .write = sel_write_enforce, 197 .llseek = generic_file_llseek, 198 }; 199 200 static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf, 201 size_t count, loff_t *ppos) 202 { 203 char tmpbuf[TMPBUFLEN]; 204 ssize_t length; 205 ino_t ino = filp->f_path.dentry->d_inode->i_ino; 206 int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ? 207 security_get_reject_unknown() : !security_get_allow_unknown(); 208 209 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown); 210 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 211 } 212 213 static const struct file_operations sel_handle_unknown_ops = { 214 .read = sel_read_handle_unknown, 215 .llseek = generic_file_llseek, 216 }; 217 218 static int sel_open_handle_status(struct inode *inode, struct file *filp) 219 { 220 struct page *status = selinux_kernel_status_page(); 221 222 if (!status) 223 return -ENOMEM; 224 225 filp->private_data = status; 226 227 return 0; 228 } 229 230 static ssize_t sel_read_handle_status(struct file *filp, char __user *buf, 231 size_t count, loff_t *ppos) 232 { 233 struct page *status = filp->private_data; 234 235 BUG_ON(!status); 236 237 return simple_read_from_buffer(buf, count, ppos, 238 page_address(status), 239 sizeof(struct selinux_kernel_status)); 240 } 241 242 static int sel_mmap_handle_status(struct file *filp, 243 struct vm_area_struct *vma) 244 { 245 struct page *status = filp->private_data; 246 unsigned long size = vma->vm_end - vma->vm_start; 247 248 BUG_ON(!status); 249 250 /* only allows one page from the head */ 251 if (vma->vm_pgoff > 0 || size != PAGE_SIZE) 252 return -EIO; 253 /* disallow writable mapping */ 254 if (vma->vm_flags & VM_WRITE) 255 return -EPERM; 256 /* disallow mprotect() turns it into writable */ 257 vma->vm_flags &= ~VM_MAYWRITE; 258 259 return remap_pfn_range(vma, vma->vm_start, 260 page_to_pfn(status), 261 size, vma->vm_page_prot); 262 } 263 264 static const struct file_operations sel_handle_status_ops = { 265 .open = sel_open_handle_status, 266 .read = sel_read_handle_status, 267 .mmap = sel_mmap_handle_status, 268 .llseek = generic_file_llseek, 269 }; 270 271 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 272 static ssize_t sel_write_disable(struct file *file, const char __user *buf, 273 size_t count, loff_t *ppos) 274 275 { 276 char *page = NULL; 277 ssize_t length; 278 int new_value; 279 280 length = -ENOMEM; 281 if (count >= PAGE_SIZE) 282 goto out; 283 284 /* No partial writes. */ 285 length = -EINVAL; 286 if (*ppos != 0) 287 goto out; 288 289 length = -ENOMEM; 290 page = (char *)get_zeroed_page(GFP_KERNEL); 291 if (!page) 292 goto out; 293 294 length = -EFAULT; 295 if (copy_from_user(page, buf, count)) 296 goto out; 297 298 length = -EINVAL; 299 if (sscanf(page, "%d", &new_value) != 1) 300 goto out; 301 302 if (new_value) { 303 length = selinux_disable(); 304 if (length) 305 goto out; 306 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS, 307 "selinux=0 auid=%u ses=%u", 308 audit_get_loginuid(current), 309 audit_get_sessionid(current)); 310 } 311 312 length = count; 313 out: 314 free_page((unsigned long) page); 315 return length; 316 } 317 #else 318 #define sel_write_disable NULL 319 #endif 320 321 static const struct file_operations sel_disable_ops = { 322 .write = sel_write_disable, 323 .llseek = generic_file_llseek, 324 }; 325 326 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf, 327 size_t count, loff_t *ppos) 328 { 329 char tmpbuf[TMPBUFLEN]; 330 ssize_t length; 331 332 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX); 333 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 334 } 335 336 static const struct file_operations sel_policyvers_ops = { 337 .read = sel_read_policyvers, 338 .llseek = generic_file_llseek, 339 }; 340 341 /* declaration for sel_write_load */ 342 static int sel_make_bools(void); 343 static int sel_make_classes(void); 344 static int sel_make_policycap(void); 345 346 /* declaration for sel_make_class_dirs */ 347 static int sel_make_dir(struct inode *dir, struct dentry *dentry, 348 unsigned long *ino); 349 350 static ssize_t sel_read_mls(struct file *filp, char __user *buf, 351 size_t count, loff_t *ppos) 352 { 353 char tmpbuf[TMPBUFLEN]; 354 ssize_t length; 355 356 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", 357 security_mls_enabled()); 358 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 359 } 360 361 static const struct file_operations sel_mls_ops = { 362 .read = sel_read_mls, 363 .llseek = generic_file_llseek, 364 }; 365 366 struct policy_load_memory { 367 size_t len; 368 void *data; 369 }; 370 371 static int sel_open_policy(struct inode *inode, struct file *filp) 372 { 373 struct policy_load_memory *plm = NULL; 374 int rc; 375 376 BUG_ON(filp->private_data); 377 378 mutex_lock(&sel_mutex); 379 380 rc = task_has_security(current, SECURITY__READ_POLICY); 381 if (rc) 382 goto err; 383 384 rc = -EBUSY; 385 if (policy_opened) 386 goto err; 387 388 rc = -ENOMEM; 389 plm = kzalloc(sizeof(*plm), GFP_KERNEL); 390 if (!plm) 391 goto err; 392 393 if (i_size_read(inode) != security_policydb_len()) { 394 mutex_lock(&inode->i_mutex); 395 i_size_write(inode, security_policydb_len()); 396 mutex_unlock(&inode->i_mutex); 397 } 398 399 rc = security_read_policy(&plm->data, &plm->len); 400 if (rc) 401 goto err; 402 403 policy_opened = 1; 404 405 filp->private_data = plm; 406 407 mutex_unlock(&sel_mutex); 408 409 return 0; 410 err: 411 mutex_unlock(&sel_mutex); 412 413 if (plm) 414 vfree(plm->data); 415 kfree(plm); 416 return rc; 417 } 418 419 static int sel_release_policy(struct inode *inode, struct file *filp) 420 { 421 struct policy_load_memory *plm = filp->private_data; 422 423 BUG_ON(!plm); 424 425 policy_opened = 0; 426 427 vfree(plm->data); 428 kfree(plm); 429 430 return 0; 431 } 432 433 static ssize_t sel_read_policy(struct file *filp, char __user *buf, 434 size_t count, loff_t *ppos) 435 { 436 struct policy_load_memory *plm = filp->private_data; 437 int ret; 438 439 mutex_lock(&sel_mutex); 440 441 ret = task_has_security(current, SECURITY__READ_POLICY); 442 if (ret) 443 goto out; 444 445 ret = simple_read_from_buffer(buf, count, ppos, plm->data, plm->len); 446 out: 447 mutex_unlock(&sel_mutex); 448 return ret; 449 } 450 451 static int sel_mmap_policy_fault(struct vm_area_struct *vma, 452 struct vm_fault *vmf) 453 { 454 struct policy_load_memory *plm = vma->vm_file->private_data; 455 unsigned long offset; 456 struct page *page; 457 458 if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE)) 459 return VM_FAULT_SIGBUS; 460 461 offset = vmf->pgoff << PAGE_SHIFT; 462 if (offset >= roundup(plm->len, PAGE_SIZE)) 463 return VM_FAULT_SIGBUS; 464 465 page = vmalloc_to_page(plm->data + offset); 466 get_page(page); 467 468 vmf->page = page; 469 470 return 0; 471 } 472 473 static struct vm_operations_struct sel_mmap_policy_ops = { 474 .fault = sel_mmap_policy_fault, 475 .page_mkwrite = sel_mmap_policy_fault, 476 }; 477 478 static int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma) 479 { 480 if (vma->vm_flags & VM_SHARED) { 481 /* do not allow mprotect to make mapping writable */ 482 vma->vm_flags &= ~VM_MAYWRITE; 483 484 if (vma->vm_flags & VM_WRITE) 485 return -EACCES; 486 } 487 488 vma->vm_flags |= VM_RESERVED; 489 vma->vm_ops = &sel_mmap_policy_ops; 490 491 return 0; 492 } 493 494 static const struct file_operations sel_policy_ops = { 495 .open = sel_open_policy, 496 .read = sel_read_policy, 497 .mmap = sel_mmap_policy, 498 .release = sel_release_policy, 499 }; 500 501 static ssize_t sel_write_load(struct file *file, const char __user *buf, 502 size_t count, loff_t *ppos) 503 504 { 505 ssize_t length; 506 void *data = NULL; 507 508 mutex_lock(&sel_mutex); 509 510 length = task_has_security(current, SECURITY__LOAD_POLICY); 511 if (length) 512 goto out; 513 514 /* No partial writes. */ 515 length = -EINVAL; 516 if (*ppos != 0) 517 goto out; 518 519 length = -EFBIG; 520 if (count > 64 * 1024 * 1024) 521 goto out; 522 523 length = -ENOMEM; 524 data = vmalloc(count); 525 if (!data) 526 goto out; 527 528 length = -EFAULT; 529 if (copy_from_user(data, buf, count) != 0) 530 goto out; 531 532 length = security_load_policy(data, count); 533 if (length) 534 goto out; 535 536 length = sel_make_bools(); 537 if (length) 538 goto out1; 539 540 length = sel_make_classes(); 541 if (length) 542 goto out1; 543 544 length = sel_make_policycap(); 545 if (length) 546 goto out1; 547 548 length = count; 549 550 out1: 551 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD, 552 "policy loaded auid=%u ses=%u", 553 audit_get_loginuid(current), 554 audit_get_sessionid(current)); 555 out: 556 mutex_unlock(&sel_mutex); 557 vfree(data); 558 return length; 559 } 560 561 static const struct file_operations sel_load_ops = { 562 .write = sel_write_load, 563 .llseek = generic_file_llseek, 564 }; 565 566 static ssize_t sel_write_context(struct file *file, char *buf, size_t size) 567 { 568 char *canon = NULL; 569 u32 sid, len; 570 ssize_t length; 571 572 length = task_has_security(current, SECURITY__CHECK_CONTEXT); 573 if (length) 574 goto out; 575 576 length = security_context_to_sid(buf, size, &sid); 577 if (length) 578 goto out; 579 580 length = security_sid_to_context(sid, &canon, &len); 581 if (length) 582 goto out; 583 584 length = -ERANGE; 585 if (len > SIMPLE_TRANSACTION_LIMIT) { 586 printk(KERN_ERR "SELinux: %s: context size (%u) exceeds " 587 "payload max\n", __func__, len); 588 goto out; 589 } 590 591 memcpy(buf, canon, len); 592 length = len; 593 out: 594 kfree(canon); 595 return length; 596 } 597 598 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf, 599 size_t count, loff_t *ppos) 600 { 601 char tmpbuf[TMPBUFLEN]; 602 ssize_t length; 603 604 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot); 605 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 606 } 607 608 static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf, 609 size_t count, loff_t *ppos) 610 { 611 char *page = NULL; 612 ssize_t length; 613 unsigned int new_value; 614 615 length = task_has_security(current, SECURITY__SETCHECKREQPROT); 616 if (length) 617 goto out; 618 619 length = -ENOMEM; 620 if (count >= PAGE_SIZE) 621 goto out; 622 623 /* No partial writes. */ 624 length = -EINVAL; 625 if (*ppos != 0) 626 goto out; 627 628 length = -ENOMEM; 629 page = (char *)get_zeroed_page(GFP_KERNEL); 630 if (!page) 631 goto out; 632 633 length = -EFAULT; 634 if (copy_from_user(page, buf, count)) 635 goto out; 636 637 length = -EINVAL; 638 if (sscanf(page, "%u", &new_value) != 1) 639 goto out; 640 641 selinux_checkreqprot = new_value ? 1 : 0; 642 length = count; 643 out: 644 free_page((unsigned long) page); 645 return length; 646 } 647 static const struct file_operations sel_checkreqprot_ops = { 648 .read = sel_read_checkreqprot, 649 .write = sel_write_checkreqprot, 650 .llseek = generic_file_llseek, 651 }; 652 653 /* 654 * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c 655 */ 656 static ssize_t sel_write_access(struct file *file, char *buf, size_t size); 657 static ssize_t sel_write_create(struct file *file, char *buf, size_t size); 658 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size); 659 static ssize_t sel_write_user(struct file *file, char *buf, size_t size); 660 static ssize_t sel_write_member(struct file *file, char *buf, size_t size); 661 662 static ssize_t (*write_op[])(struct file *, char *, size_t) = { 663 [SEL_ACCESS] = sel_write_access, 664 [SEL_CREATE] = sel_write_create, 665 [SEL_RELABEL] = sel_write_relabel, 666 [SEL_USER] = sel_write_user, 667 [SEL_MEMBER] = sel_write_member, 668 [SEL_CONTEXT] = sel_write_context, 669 }; 670 671 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos) 672 { 673 ino_t ino = file->f_path.dentry->d_inode->i_ino; 674 char *data; 675 ssize_t rv; 676 677 if (ino >= ARRAY_SIZE(write_op) || !write_op[ino]) 678 return -EINVAL; 679 680 data = simple_transaction_get(file, buf, size); 681 if (IS_ERR(data)) 682 return PTR_ERR(data); 683 684 rv = write_op[ino](file, data, size); 685 if (rv > 0) { 686 simple_transaction_set(file, rv); 687 rv = size; 688 } 689 return rv; 690 } 691 692 static const struct file_operations transaction_ops = { 693 .write = selinux_transaction_write, 694 .read = simple_transaction_read, 695 .release = simple_transaction_release, 696 .llseek = generic_file_llseek, 697 }; 698 699 /* 700 * payload - write methods 701 * If the method has a response, the response should be put in buf, 702 * and the length returned. Otherwise return 0 or and -error. 703 */ 704 705 static ssize_t sel_write_access(struct file *file, char *buf, size_t size) 706 { 707 char *scon = NULL, *tcon = NULL; 708 u32 ssid, tsid; 709 u16 tclass; 710 struct av_decision avd; 711 ssize_t length; 712 713 length = task_has_security(current, SECURITY__COMPUTE_AV); 714 if (length) 715 goto out; 716 717 length = -ENOMEM; 718 scon = kzalloc(size + 1, GFP_KERNEL); 719 if (!scon) 720 goto out; 721 722 length = -ENOMEM; 723 tcon = kzalloc(size + 1, GFP_KERNEL); 724 if (!tcon) 725 goto out; 726 727 length = -EINVAL; 728 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3) 729 goto out; 730 731 length = security_context_to_sid(scon, strlen(scon) + 1, &ssid); 732 if (length) 733 goto out; 734 735 length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid); 736 if (length) 737 goto out; 738 739 security_compute_av_user(ssid, tsid, tclass, &avd); 740 741 length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, 742 "%x %x %x %x %u %x", 743 avd.allowed, 0xffffffff, 744 avd.auditallow, avd.auditdeny, 745 avd.seqno, avd.flags); 746 out: 747 kfree(tcon); 748 kfree(scon); 749 return length; 750 } 751 752 static inline int hexcode_to_int(int code) { 753 if (code == '\0' || !isxdigit(code)) 754 return -1; 755 if (isdigit(code)) 756 return code - '0'; 757 return tolower(code) - 'a' + 10; 758 } 759 760 static ssize_t sel_write_create(struct file *file, char *buf, size_t size) 761 { 762 char *scon = NULL, *tcon = NULL; 763 char *namebuf = NULL, *objname = NULL; 764 u32 ssid, tsid, newsid; 765 u16 tclass; 766 ssize_t length; 767 char *newcon = NULL; 768 u32 len; 769 int nargs; 770 771 length = task_has_security(current, SECURITY__COMPUTE_CREATE); 772 if (length) 773 goto out; 774 775 length = -ENOMEM; 776 scon = kzalloc(size + 1, GFP_KERNEL); 777 if (!scon) 778 goto out; 779 780 length = -ENOMEM; 781 tcon = kzalloc(size + 1, GFP_KERNEL); 782 if (!tcon) 783 goto out; 784 785 length = -ENOMEM; 786 namebuf = kzalloc(size + 1, GFP_KERNEL); 787 if (!namebuf) 788 goto out; 789 790 length = -EINVAL; 791 nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf); 792 if (nargs < 3 || nargs > 4) 793 goto out; 794 if (nargs == 4) { 795 /* 796 * If and when the name of new object to be queried contains 797 * either whitespace or multibyte characters, they shall be 798 * encoded based on the percentage-encoding rule. 799 * If not encoded, the sscanf logic picks up only left-half 800 * of the supplied name; splitted by a whitespace unexpectedly. 801 */ 802 char *r, *w; 803 int c1, c2; 804 805 r = w = namebuf; 806 do { 807 c1 = *r++; 808 if (c1 == '+') 809 c1 = ' '; 810 else if (c1 == '%') { 811 if ((c1 = hexcode_to_int(*r++)) < 0) 812 goto out; 813 if ((c2 = hexcode_to_int(*r++)) < 0) 814 goto out; 815 c1 = (c1 << 4) | c2; 816 } 817 *w++ = c1; 818 } while (c1 != '\0'); 819 820 objname = namebuf; 821 } 822 823 length = security_context_to_sid(scon, strlen(scon) + 1, &ssid); 824 if (length) 825 goto out; 826 827 length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid); 828 if (length) 829 goto out; 830 831 length = security_transition_sid_user(ssid, tsid, tclass, 832 objname, &newsid); 833 if (length) 834 goto out; 835 836 length = security_sid_to_context(newsid, &newcon, &len); 837 if (length) 838 goto out; 839 840 length = -ERANGE; 841 if (len > SIMPLE_TRANSACTION_LIMIT) { 842 printk(KERN_ERR "SELinux: %s: context size (%u) exceeds " 843 "payload max\n", __func__, len); 844 goto out; 845 } 846 847 memcpy(buf, newcon, len); 848 length = len; 849 out: 850 kfree(newcon); 851 kfree(namebuf); 852 kfree(tcon); 853 kfree(scon); 854 return length; 855 } 856 857 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size) 858 { 859 char *scon = NULL, *tcon = NULL; 860 u32 ssid, tsid, newsid; 861 u16 tclass; 862 ssize_t length; 863 char *newcon = NULL; 864 u32 len; 865 866 length = task_has_security(current, SECURITY__COMPUTE_RELABEL); 867 if (length) 868 goto out; 869 870 length = -ENOMEM; 871 scon = kzalloc(size + 1, GFP_KERNEL); 872 if (!scon) 873 goto out; 874 875 length = -ENOMEM; 876 tcon = kzalloc(size + 1, GFP_KERNEL); 877 if (!tcon) 878 goto out; 879 880 length = -EINVAL; 881 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3) 882 goto out; 883 884 length = security_context_to_sid(scon, strlen(scon) + 1, &ssid); 885 if (length) 886 goto out; 887 888 length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid); 889 if (length) 890 goto out; 891 892 length = security_change_sid(ssid, tsid, tclass, &newsid); 893 if (length) 894 goto out; 895 896 length = security_sid_to_context(newsid, &newcon, &len); 897 if (length) 898 goto out; 899 900 length = -ERANGE; 901 if (len > SIMPLE_TRANSACTION_LIMIT) 902 goto out; 903 904 memcpy(buf, newcon, len); 905 length = len; 906 out: 907 kfree(newcon); 908 kfree(tcon); 909 kfree(scon); 910 return length; 911 } 912 913 static ssize_t sel_write_user(struct file *file, char *buf, size_t size) 914 { 915 char *con = NULL, *user = NULL, *ptr; 916 u32 sid, *sids = NULL; 917 ssize_t length; 918 char *newcon; 919 int i, rc; 920 u32 len, nsids; 921 922 length = task_has_security(current, SECURITY__COMPUTE_USER); 923 if (length) 924 goto out; 925 926 length = -ENOMEM; 927 con = kzalloc(size + 1, GFP_KERNEL); 928 if (!con) 929 goto out; 930 931 length = -ENOMEM; 932 user = kzalloc(size + 1, GFP_KERNEL); 933 if (!user) 934 goto out; 935 936 length = -EINVAL; 937 if (sscanf(buf, "%s %s", con, user) != 2) 938 goto out; 939 940 length = security_context_to_sid(con, strlen(con) + 1, &sid); 941 if (length) 942 goto out; 943 944 length = security_get_user_sids(sid, user, &sids, &nsids); 945 if (length) 946 goto out; 947 948 length = sprintf(buf, "%u", nsids) + 1; 949 ptr = buf + length; 950 for (i = 0; i < nsids; i++) { 951 rc = security_sid_to_context(sids[i], &newcon, &len); 952 if (rc) { 953 length = rc; 954 goto out; 955 } 956 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) { 957 kfree(newcon); 958 length = -ERANGE; 959 goto out; 960 } 961 memcpy(ptr, newcon, len); 962 kfree(newcon); 963 ptr += len; 964 length += len; 965 } 966 out: 967 kfree(sids); 968 kfree(user); 969 kfree(con); 970 return length; 971 } 972 973 static ssize_t sel_write_member(struct file *file, char *buf, size_t size) 974 { 975 char *scon = NULL, *tcon = NULL; 976 u32 ssid, tsid, newsid; 977 u16 tclass; 978 ssize_t length; 979 char *newcon = NULL; 980 u32 len; 981 982 length = task_has_security(current, SECURITY__COMPUTE_MEMBER); 983 if (length) 984 goto out; 985 986 length = -ENOMEM; 987 scon = kzalloc(size + 1, GFP_KERNEL); 988 if (!scon) 989 goto out; 990 991 length = -ENOMEM; 992 tcon = kzalloc(size + 1, GFP_KERNEL); 993 if (!tcon) 994 goto out; 995 996 length = -EINVAL; 997 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3) 998 goto out; 999 1000 length = security_context_to_sid(scon, strlen(scon) + 1, &ssid); 1001 if (length) 1002 goto out; 1003 1004 length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid); 1005 if (length) 1006 goto out; 1007 1008 length = security_member_sid(ssid, tsid, tclass, &newsid); 1009 if (length) 1010 goto out; 1011 1012 length = security_sid_to_context(newsid, &newcon, &len); 1013 if (length) 1014 goto out; 1015 1016 length = -ERANGE; 1017 if (len > SIMPLE_TRANSACTION_LIMIT) { 1018 printk(KERN_ERR "SELinux: %s: context size (%u) exceeds " 1019 "payload max\n", __func__, len); 1020 goto out; 1021 } 1022 1023 memcpy(buf, newcon, len); 1024 length = len; 1025 out: 1026 kfree(newcon); 1027 kfree(tcon); 1028 kfree(scon); 1029 return length; 1030 } 1031 1032 static struct inode *sel_make_inode(struct super_block *sb, int mode) 1033 { 1034 struct inode *ret = new_inode(sb); 1035 1036 if (ret) { 1037 ret->i_mode = mode; 1038 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME; 1039 } 1040 return ret; 1041 } 1042 1043 static ssize_t sel_read_bool(struct file *filep, char __user *buf, 1044 size_t count, loff_t *ppos) 1045 { 1046 char *page = NULL; 1047 ssize_t length; 1048 ssize_t ret; 1049 int cur_enforcing; 1050 struct inode *inode = filep->f_path.dentry->d_inode; 1051 unsigned index = inode->i_ino & SEL_INO_MASK; 1052 const char *name = filep->f_path.dentry->d_name.name; 1053 1054 mutex_lock(&sel_mutex); 1055 1056 ret = -EINVAL; 1057 if (index >= bool_num || strcmp(name, bool_pending_names[index])) 1058 goto out; 1059 1060 ret = -ENOMEM; 1061 page = (char *)get_zeroed_page(GFP_KERNEL); 1062 if (!page) 1063 goto out; 1064 1065 cur_enforcing = security_get_bool_value(index); 1066 if (cur_enforcing < 0) { 1067 ret = cur_enforcing; 1068 goto out; 1069 } 1070 length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing, 1071 bool_pending_values[index]); 1072 ret = simple_read_from_buffer(buf, count, ppos, page, length); 1073 out: 1074 mutex_unlock(&sel_mutex); 1075 free_page((unsigned long)page); 1076 return ret; 1077 } 1078 1079 static ssize_t sel_write_bool(struct file *filep, const char __user *buf, 1080 size_t count, loff_t *ppos) 1081 { 1082 char *page = NULL; 1083 ssize_t length; 1084 int new_value; 1085 struct inode *inode = filep->f_path.dentry->d_inode; 1086 unsigned index = inode->i_ino & SEL_INO_MASK; 1087 const char *name = filep->f_path.dentry->d_name.name; 1088 1089 mutex_lock(&sel_mutex); 1090 1091 length = task_has_security(current, SECURITY__SETBOOL); 1092 if (length) 1093 goto out; 1094 1095 length = -EINVAL; 1096 if (index >= bool_num || strcmp(name, bool_pending_names[index])) 1097 goto out; 1098 1099 length = -ENOMEM; 1100 if (count >= PAGE_SIZE) 1101 goto out; 1102 1103 /* No partial writes. */ 1104 length = -EINVAL; 1105 if (*ppos != 0) 1106 goto out; 1107 1108 length = -ENOMEM; 1109 page = (char *)get_zeroed_page(GFP_KERNEL); 1110 if (!page) 1111 goto out; 1112 1113 length = -EFAULT; 1114 if (copy_from_user(page, buf, count)) 1115 goto out; 1116 1117 length = -EINVAL; 1118 if (sscanf(page, "%d", &new_value) != 1) 1119 goto out; 1120 1121 if (new_value) 1122 new_value = 1; 1123 1124 bool_pending_values[index] = new_value; 1125 length = count; 1126 1127 out: 1128 mutex_unlock(&sel_mutex); 1129 free_page((unsigned long) page); 1130 return length; 1131 } 1132 1133 static const struct file_operations sel_bool_ops = { 1134 .read = sel_read_bool, 1135 .write = sel_write_bool, 1136 .llseek = generic_file_llseek, 1137 }; 1138 1139 static ssize_t sel_commit_bools_write(struct file *filep, 1140 const char __user *buf, 1141 size_t count, loff_t *ppos) 1142 { 1143 char *page = NULL; 1144 ssize_t length; 1145 int new_value; 1146 1147 mutex_lock(&sel_mutex); 1148 1149 length = task_has_security(current, SECURITY__SETBOOL); 1150 if (length) 1151 goto out; 1152 1153 length = -ENOMEM; 1154 if (count >= PAGE_SIZE) 1155 goto out; 1156 1157 /* No partial writes. */ 1158 length = -EINVAL; 1159 if (*ppos != 0) 1160 goto out; 1161 1162 length = -ENOMEM; 1163 page = (char *)get_zeroed_page(GFP_KERNEL); 1164 if (!page) 1165 goto out; 1166 1167 length = -EFAULT; 1168 if (copy_from_user(page, buf, count)) 1169 goto out; 1170 1171 length = -EINVAL; 1172 if (sscanf(page, "%d", &new_value) != 1) 1173 goto out; 1174 1175 length = 0; 1176 if (new_value && bool_pending_values) 1177 length = security_set_bools(bool_num, bool_pending_values); 1178 1179 if (!length) 1180 length = count; 1181 1182 out: 1183 mutex_unlock(&sel_mutex); 1184 free_page((unsigned long) page); 1185 return length; 1186 } 1187 1188 static const struct file_operations sel_commit_bools_ops = { 1189 .write = sel_commit_bools_write, 1190 .llseek = generic_file_llseek, 1191 }; 1192 1193 static void sel_remove_entries(struct dentry *de) 1194 { 1195 struct list_head *node; 1196 1197 spin_lock(&de->d_lock); 1198 node = de->d_subdirs.next; 1199 while (node != &de->d_subdirs) { 1200 struct dentry *d = list_entry(node, struct dentry, d_u.d_child); 1201 1202 spin_lock_nested(&d->d_lock, DENTRY_D_LOCK_NESTED); 1203 list_del_init(node); 1204 1205 if (d->d_inode) { 1206 dget_dlock(d); 1207 spin_unlock(&de->d_lock); 1208 spin_unlock(&d->d_lock); 1209 d_delete(d); 1210 simple_unlink(de->d_inode, d); 1211 dput(d); 1212 spin_lock(&de->d_lock); 1213 } else 1214 spin_unlock(&d->d_lock); 1215 node = de->d_subdirs.next; 1216 } 1217 1218 spin_unlock(&de->d_lock); 1219 } 1220 1221 #define BOOL_DIR_NAME "booleans" 1222 1223 static int sel_make_bools(void) 1224 { 1225 int i, ret; 1226 ssize_t len; 1227 struct dentry *dentry = NULL; 1228 struct dentry *dir = bool_dir; 1229 struct inode *inode = NULL; 1230 struct inode_security_struct *isec; 1231 char **names = NULL, *page; 1232 int num; 1233 int *values = NULL; 1234 u32 sid; 1235 1236 /* remove any existing files */ 1237 for (i = 0; i < bool_num; i++) 1238 kfree(bool_pending_names[i]); 1239 kfree(bool_pending_names); 1240 kfree(bool_pending_values); 1241 bool_pending_names = NULL; 1242 bool_pending_values = NULL; 1243 1244 sel_remove_entries(dir); 1245 1246 ret = -ENOMEM; 1247 page = (char *)get_zeroed_page(GFP_KERNEL); 1248 if (!page) 1249 goto out; 1250 1251 ret = security_get_bools(&num, &names, &values); 1252 if (ret) 1253 goto out; 1254 1255 for (i = 0; i < num; i++) { 1256 ret = -ENOMEM; 1257 dentry = d_alloc_name(dir, names[i]); 1258 if (!dentry) 1259 goto out; 1260 1261 ret = -ENOMEM; 1262 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR); 1263 if (!inode) 1264 goto out; 1265 1266 ret = -EINVAL; 1267 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]); 1268 if (len < 0) 1269 goto out; 1270 1271 ret = -ENAMETOOLONG; 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 dentry *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 struct inode *inode; 1498 char *con; 1499 u32 sid, len; 1500 ssize_t ret; 1501 1502 inode = file->f_path.dentry->d_inode; 1503 sid = inode->i_ino&SEL_INO_MASK; 1504 ret = security_sid_to_context(sid, &con, &len); 1505 if (ret) 1506 return ret; 1507 1508 ret = simple_read_from_buffer(buf, count, ppos, con, len); 1509 kfree(con); 1510 return ret; 1511 } 1512 1513 static const struct file_operations sel_initcon_ops = { 1514 .read = sel_read_initcon, 1515 .llseek = generic_file_llseek, 1516 }; 1517 1518 static int sel_make_initcon_files(struct dentry *dir) 1519 { 1520 int i; 1521 1522 for (i = 1; i <= SECINITSID_NUM; i++) { 1523 struct inode *inode; 1524 struct dentry *dentry; 1525 dentry = d_alloc_name(dir, security_get_initial_sid_context(i)); 1526 if (!dentry) 1527 return -ENOMEM; 1528 1529 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO); 1530 if (!inode) 1531 return -ENOMEM; 1532 1533 inode->i_fop = &sel_initcon_ops; 1534 inode->i_ino = i|SEL_INITCON_INO_OFFSET; 1535 d_add(dentry, inode); 1536 } 1537 1538 return 0; 1539 } 1540 1541 static inline unsigned int sel_div(unsigned long a, unsigned long b) 1542 { 1543 return a / b - (a % b < 0); 1544 } 1545 1546 static inline unsigned long sel_class_to_ino(u16 class) 1547 { 1548 return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET; 1549 } 1550 1551 static inline u16 sel_ino_to_class(unsigned long ino) 1552 { 1553 return sel_div(ino & SEL_INO_MASK, SEL_VEC_MAX + 1); 1554 } 1555 1556 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm) 1557 { 1558 return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET; 1559 } 1560 1561 static inline u32 sel_ino_to_perm(unsigned long ino) 1562 { 1563 return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1); 1564 } 1565 1566 static ssize_t sel_read_class(struct file *file, char __user *buf, 1567 size_t count, loff_t *ppos) 1568 { 1569 ssize_t rc, len; 1570 char *page; 1571 unsigned long ino = file->f_path.dentry->d_inode->i_ino; 1572 1573 page = (char *)__get_free_page(GFP_KERNEL); 1574 if (!page) 1575 return -ENOMEM; 1576 1577 len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_class(ino)); 1578 rc = simple_read_from_buffer(buf, count, ppos, page, len); 1579 free_page((unsigned long)page); 1580 1581 return rc; 1582 } 1583 1584 static const struct file_operations sel_class_ops = { 1585 .read = sel_read_class, 1586 .llseek = generic_file_llseek, 1587 }; 1588 1589 static ssize_t sel_read_perm(struct file *file, char __user *buf, 1590 size_t count, loff_t *ppos) 1591 { 1592 ssize_t rc, len; 1593 char *page; 1594 unsigned long ino = file->f_path.dentry->d_inode->i_ino; 1595 1596 page = (char *)__get_free_page(GFP_KERNEL); 1597 if (!page) 1598 return -ENOMEM; 1599 1600 len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_perm(ino)); 1601 rc = simple_read_from_buffer(buf, count, ppos, page, len); 1602 free_page((unsigned long)page); 1603 1604 return rc; 1605 } 1606 1607 static const struct file_operations sel_perm_ops = { 1608 .read = sel_read_perm, 1609 .llseek = generic_file_llseek, 1610 }; 1611 1612 static ssize_t sel_read_policycap(struct file *file, char __user *buf, 1613 size_t count, loff_t *ppos) 1614 { 1615 int value; 1616 char tmpbuf[TMPBUFLEN]; 1617 ssize_t length; 1618 unsigned long i_ino = file->f_path.dentry->d_inode->i_ino; 1619 1620 value = security_policycap_supported(i_ino & SEL_INO_MASK); 1621 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value); 1622 1623 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1624 } 1625 1626 static const struct file_operations sel_policycap_ops = { 1627 .read = sel_read_policycap, 1628 .llseek = generic_file_llseek, 1629 }; 1630 1631 static int sel_make_perm_files(char *objclass, int classvalue, 1632 struct dentry *dir) 1633 { 1634 int i, rc, nperms; 1635 char **perms; 1636 1637 rc = security_get_permissions(objclass, &perms, &nperms); 1638 if (rc) 1639 return rc; 1640 1641 for (i = 0; i < nperms; i++) { 1642 struct inode *inode; 1643 struct dentry *dentry; 1644 1645 rc = -ENOMEM; 1646 dentry = d_alloc_name(dir, perms[i]); 1647 if (!dentry) 1648 goto out; 1649 1650 rc = -ENOMEM; 1651 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO); 1652 if (!inode) 1653 goto out; 1654 1655 inode->i_fop = &sel_perm_ops; 1656 /* i+1 since perm values are 1-indexed */ 1657 inode->i_ino = sel_perm_to_ino(classvalue, i + 1); 1658 d_add(dentry, inode); 1659 } 1660 rc = 0; 1661 out: 1662 for (i = 0; i < nperms; i++) 1663 kfree(perms[i]); 1664 kfree(perms); 1665 return rc; 1666 } 1667 1668 static int sel_make_class_dir_entries(char *classname, int index, 1669 struct dentry *dir) 1670 { 1671 struct dentry *dentry = NULL; 1672 struct inode *inode = NULL; 1673 int rc; 1674 1675 dentry = d_alloc_name(dir, "index"); 1676 if (!dentry) 1677 return -ENOMEM; 1678 1679 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO); 1680 if (!inode) 1681 return -ENOMEM; 1682 1683 inode->i_fop = &sel_class_ops; 1684 inode->i_ino = sel_class_to_ino(index); 1685 d_add(dentry, inode); 1686 1687 dentry = d_alloc_name(dir, "perms"); 1688 if (!dentry) 1689 return -ENOMEM; 1690 1691 rc = sel_make_dir(dir->d_inode, dentry, &last_class_ino); 1692 if (rc) 1693 return rc; 1694 1695 rc = sel_make_perm_files(classname, index, dentry); 1696 1697 return rc; 1698 } 1699 1700 static void sel_remove_classes(void) 1701 { 1702 struct list_head *class_node; 1703 1704 list_for_each(class_node, &class_dir->d_subdirs) { 1705 struct dentry *class_subdir = list_entry(class_node, 1706 struct dentry, d_u.d_child); 1707 struct list_head *class_subdir_node; 1708 1709 list_for_each(class_subdir_node, &class_subdir->d_subdirs) { 1710 struct dentry *d = list_entry(class_subdir_node, 1711 struct dentry, d_u.d_child); 1712 1713 if (d->d_inode) 1714 if (d->d_inode->i_mode & S_IFDIR) 1715 sel_remove_entries(d); 1716 } 1717 1718 sel_remove_entries(class_subdir); 1719 } 1720 1721 sel_remove_entries(class_dir); 1722 } 1723 1724 static int sel_make_classes(void) 1725 { 1726 int rc, nclasses, i; 1727 char **classes; 1728 1729 /* delete any existing entries */ 1730 sel_remove_classes(); 1731 1732 rc = security_get_classes(&classes, &nclasses); 1733 if (rc) 1734 return rc; 1735 1736 /* +2 since classes are 1-indexed */ 1737 last_class_ino = sel_class_to_ino(nclasses + 2); 1738 1739 for (i = 0; i < nclasses; i++) { 1740 struct dentry *class_name_dir; 1741 1742 rc = -ENOMEM; 1743 class_name_dir = d_alloc_name(class_dir, classes[i]); 1744 if (!class_name_dir) 1745 goto out; 1746 1747 rc = sel_make_dir(class_dir->d_inode, class_name_dir, 1748 &last_class_ino); 1749 if (rc) 1750 goto out; 1751 1752 /* i+1 since class values are 1-indexed */ 1753 rc = sel_make_class_dir_entries(classes[i], i + 1, 1754 class_name_dir); 1755 if (rc) 1756 goto out; 1757 } 1758 rc = 0; 1759 out: 1760 for (i = 0; i < nclasses; i++) 1761 kfree(classes[i]); 1762 kfree(classes); 1763 return rc; 1764 } 1765 1766 static int sel_make_policycap(void) 1767 { 1768 unsigned int iter; 1769 struct dentry *dentry = NULL; 1770 struct inode *inode = NULL; 1771 1772 sel_remove_entries(policycap_dir); 1773 1774 for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) { 1775 if (iter < ARRAY_SIZE(policycap_names)) 1776 dentry = d_alloc_name(policycap_dir, 1777 policycap_names[iter]); 1778 else 1779 dentry = d_alloc_name(policycap_dir, "unknown"); 1780 1781 if (dentry == NULL) 1782 return -ENOMEM; 1783 1784 inode = sel_make_inode(policycap_dir->d_sb, S_IFREG | S_IRUGO); 1785 if (inode == NULL) 1786 return -ENOMEM; 1787 1788 inode->i_fop = &sel_policycap_ops; 1789 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET; 1790 d_add(dentry, inode); 1791 } 1792 1793 return 0; 1794 } 1795 1796 static int sel_make_dir(struct inode *dir, struct dentry *dentry, 1797 unsigned long *ino) 1798 { 1799 struct inode *inode; 1800 1801 inode = sel_make_inode(dir->i_sb, S_IFDIR | S_IRUGO | S_IXUGO); 1802 if (!inode) 1803 return -ENOMEM; 1804 1805 inode->i_op = &simple_dir_inode_operations; 1806 inode->i_fop = &simple_dir_operations; 1807 inode->i_ino = ++(*ino); 1808 /* directory inodes start off with i_nlink == 2 (for "." entry) */ 1809 inc_nlink(inode); 1810 d_add(dentry, inode); 1811 /* bump link count on parent directory, too */ 1812 inc_nlink(dir); 1813 1814 return 0; 1815 } 1816 1817 static int sel_fill_super(struct super_block *sb, void *data, int silent) 1818 { 1819 int ret; 1820 struct dentry *dentry; 1821 struct inode *inode, *root_inode; 1822 struct inode_security_struct *isec; 1823 1824 static struct tree_descr selinux_files[] = { 1825 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR}, 1826 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR}, 1827 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO}, 1828 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO}, 1829 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO}, 1830 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO}, 1831 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO}, 1832 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO}, 1833 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR}, 1834 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO}, 1835 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR}, 1836 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO}, 1837 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR}, 1838 [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO}, 1839 [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO}, 1840 [SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO}, 1841 [SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUSR}, 1842 /* last one */ {""} 1843 }; 1844 ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files); 1845 if (ret) 1846 goto err; 1847 1848 root_inode = sb->s_root->d_inode; 1849 1850 ret = -ENOMEM; 1851 dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME); 1852 if (!dentry) 1853 goto err; 1854 1855 ret = sel_make_dir(root_inode, dentry, &sel_last_ino); 1856 if (ret) 1857 goto err; 1858 1859 bool_dir = dentry; 1860 1861 ret = -ENOMEM; 1862 dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME); 1863 if (!dentry) 1864 goto err; 1865 1866 ret = -ENOMEM; 1867 inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO); 1868 if (!inode) 1869 goto err; 1870 1871 inode->i_ino = ++sel_last_ino; 1872 isec = (struct inode_security_struct *)inode->i_security; 1873 isec->sid = SECINITSID_DEVNULL; 1874 isec->sclass = SECCLASS_CHR_FILE; 1875 isec->initialized = 1; 1876 1877 init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3)); 1878 d_add(dentry, inode); 1879 selinux_null = dentry; 1880 1881 ret = -ENOMEM; 1882 dentry = d_alloc_name(sb->s_root, "avc"); 1883 if (!dentry) 1884 goto err; 1885 1886 ret = sel_make_dir(root_inode, dentry, &sel_last_ino); 1887 if (ret) 1888 goto err; 1889 1890 ret = sel_make_avc_files(dentry); 1891 if (ret) 1892 goto err; 1893 1894 ret = -ENOMEM; 1895 dentry = d_alloc_name(sb->s_root, "initial_contexts"); 1896 if (!dentry) 1897 goto err; 1898 1899 ret = sel_make_dir(root_inode, dentry, &sel_last_ino); 1900 if (ret) 1901 goto err; 1902 1903 ret = sel_make_initcon_files(dentry); 1904 if (ret) 1905 goto err; 1906 1907 ret = -ENOMEM; 1908 dentry = d_alloc_name(sb->s_root, "class"); 1909 if (!dentry) 1910 goto err; 1911 1912 ret = sel_make_dir(root_inode, dentry, &sel_last_ino); 1913 if (ret) 1914 goto err; 1915 1916 class_dir = dentry; 1917 1918 ret = -ENOMEM; 1919 dentry = d_alloc_name(sb->s_root, "policy_capabilities"); 1920 if (!dentry) 1921 goto err; 1922 1923 ret = sel_make_dir(root_inode, dentry, &sel_last_ino); 1924 if (ret) 1925 goto err; 1926 1927 policycap_dir = dentry; 1928 1929 return 0; 1930 err: 1931 printk(KERN_ERR "SELinux: %s: failed while creating inodes\n", 1932 __func__); 1933 return ret; 1934 } 1935 1936 static struct dentry *sel_mount(struct file_system_type *fs_type, 1937 int flags, const char *dev_name, void *data) 1938 { 1939 return mount_single(fs_type, flags, data, sel_fill_super); 1940 } 1941 1942 static struct file_system_type sel_fs_type = { 1943 .name = "selinuxfs", 1944 .mount = sel_mount, 1945 .kill_sb = kill_litter_super, 1946 }; 1947 1948 struct vfsmount *selinuxfs_mount; 1949 static struct kobject *selinuxfs_kobj; 1950 1951 static int __init init_sel_fs(void) 1952 { 1953 int err; 1954 1955 if (!selinux_enabled) 1956 return 0; 1957 1958 selinuxfs_kobj = kobject_create_and_add("selinux", fs_kobj); 1959 if (!selinuxfs_kobj) 1960 return -ENOMEM; 1961 1962 err = register_filesystem(&sel_fs_type); 1963 if (err) { 1964 kobject_put(selinuxfs_kobj); 1965 return err; 1966 } 1967 1968 selinuxfs_mount = kern_mount(&sel_fs_type); 1969 if (IS_ERR(selinuxfs_mount)) { 1970 printk(KERN_ERR "selinuxfs: could not mount!\n"); 1971 err = PTR_ERR(selinuxfs_mount); 1972 selinuxfs_mount = NULL; 1973 } 1974 1975 return err; 1976 } 1977 1978 __initcall(init_sel_fs); 1979 1980 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 1981 void exit_sel_fs(void) 1982 { 1983 kobject_put(selinuxfs_kobj); 1984 kern_unmount(selinuxfs_mount); 1985 unregister_filesystem(&sel_fs_type); 1986 } 1987 #endif 1988