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