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 struct dentry *sel_make_dir(struct dentry *dir, const char *name, 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 ssize_t sel_write_create(struct file *file, char *buf, size_t size) 753 { 754 char *scon = NULL, *tcon = NULL; 755 char *namebuf = NULL, *objname = NULL; 756 u32 ssid, tsid, newsid; 757 u16 tclass; 758 ssize_t length; 759 char *newcon = NULL; 760 u32 len; 761 int nargs; 762 763 length = task_has_security(current, SECURITY__COMPUTE_CREATE); 764 if (length) 765 goto out; 766 767 length = -ENOMEM; 768 scon = kzalloc(size + 1, GFP_KERNEL); 769 if (!scon) 770 goto out; 771 772 length = -ENOMEM; 773 tcon = kzalloc(size + 1, GFP_KERNEL); 774 if (!tcon) 775 goto out; 776 777 length = -ENOMEM; 778 namebuf = kzalloc(size + 1, GFP_KERNEL); 779 if (!namebuf) 780 goto out; 781 782 length = -EINVAL; 783 nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf); 784 if (nargs < 3 || nargs > 4) 785 goto out; 786 if (nargs == 4) { 787 /* 788 * If and when the name of new object to be queried contains 789 * either whitespace or multibyte characters, they shall be 790 * encoded based on the percentage-encoding rule. 791 * If not encoded, the sscanf logic picks up only left-half 792 * of the supplied name; splitted by a whitespace unexpectedly. 793 */ 794 char *r, *w; 795 int c1, c2; 796 797 r = w = namebuf; 798 do { 799 c1 = *r++; 800 if (c1 == '+') 801 c1 = ' '; 802 else if (c1 == '%') { 803 c1 = hex_to_bin(*r++); 804 if (c1 < 0) 805 goto out; 806 c2 = hex_to_bin(*r++); 807 if (c2 < 0) 808 goto out; 809 c1 = (c1 << 4) | c2; 810 } 811 *w++ = c1; 812 } while (c1 != '\0'); 813 814 objname = namebuf; 815 } 816 817 length = security_context_to_sid(scon, strlen(scon) + 1, &ssid); 818 if (length) 819 goto out; 820 821 length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid); 822 if (length) 823 goto out; 824 825 length = security_transition_sid_user(ssid, tsid, tclass, 826 objname, &newsid); 827 if (length) 828 goto out; 829 830 length = security_sid_to_context(newsid, &newcon, &len); 831 if (length) 832 goto out; 833 834 length = -ERANGE; 835 if (len > SIMPLE_TRANSACTION_LIMIT) { 836 printk(KERN_ERR "SELinux: %s: context size (%u) exceeds " 837 "payload max\n", __func__, len); 838 goto out; 839 } 840 841 memcpy(buf, newcon, len); 842 length = len; 843 out: 844 kfree(newcon); 845 kfree(namebuf); 846 kfree(tcon); 847 kfree(scon); 848 return length; 849 } 850 851 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size) 852 { 853 char *scon = NULL, *tcon = NULL; 854 u32 ssid, tsid, newsid; 855 u16 tclass; 856 ssize_t length; 857 char *newcon = NULL; 858 u32 len; 859 860 length = task_has_security(current, SECURITY__COMPUTE_RELABEL); 861 if (length) 862 goto out; 863 864 length = -ENOMEM; 865 scon = kzalloc(size + 1, GFP_KERNEL); 866 if (!scon) 867 goto out; 868 869 length = -ENOMEM; 870 tcon = kzalloc(size + 1, GFP_KERNEL); 871 if (!tcon) 872 goto out; 873 874 length = -EINVAL; 875 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3) 876 goto out; 877 878 length = security_context_to_sid(scon, strlen(scon) + 1, &ssid); 879 if (length) 880 goto out; 881 882 length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid); 883 if (length) 884 goto out; 885 886 length = security_change_sid(ssid, tsid, tclass, &newsid); 887 if (length) 888 goto out; 889 890 length = security_sid_to_context(newsid, &newcon, &len); 891 if (length) 892 goto out; 893 894 length = -ERANGE; 895 if (len > SIMPLE_TRANSACTION_LIMIT) 896 goto out; 897 898 memcpy(buf, newcon, len); 899 length = len; 900 out: 901 kfree(newcon); 902 kfree(tcon); 903 kfree(scon); 904 return length; 905 } 906 907 static ssize_t sel_write_user(struct file *file, char *buf, size_t size) 908 { 909 char *con = NULL, *user = NULL, *ptr; 910 u32 sid, *sids = NULL; 911 ssize_t length; 912 char *newcon; 913 int i, rc; 914 u32 len, nsids; 915 916 length = task_has_security(current, SECURITY__COMPUTE_USER); 917 if (length) 918 goto out; 919 920 length = -ENOMEM; 921 con = kzalloc(size + 1, GFP_KERNEL); 922 if (!con) 923 goto out; 924 925 length = -ENOMEM; 926 user = kzalloc(size + 1, GFP_KERNEL); 927 if (!user) 928 goto out; 929 930 length = -EINVAL; 931 if (sscanf(buf, "%s %s", con, user) != 2) 932 goto out; 933 934 length = security_context_to_sid(con, strlen(con) + 1, &sid); 935 if (length) 936 goto out; 937 938 length = security_get_user_sids(sid, user, &sids, &nsids); 939 if (length) 940 goto out; 941 942 length = sprintf(buf, "%u", nsids) + 1; 943 ptr = buf + length; 944 for (i = 0; i < nsids; i++) { 945 rc = security_sid_to_context(sids[i], &newcon, &len); 946 if (rc) { 947 length = rc; 948 goto out; 949 } 950 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) { 951 kfree(newcon); 952 length = -ERANGE; 953 goto out; 954 } 955 memcpy(ptr, newcon, len); 956 kfree(newcon); 957 ptr += len; 958 length += len; 959 } 960 out: 961 kfree(sids); 962 kfree(user); 963 kfree(con); 964 return length; 965 } 966 967 static ssize_t sel_write_member(struct file *file, char *buf, size_t size) 968 { 969 char *scon = NULL, *tcon = NULL; 970 u32 ssid, tsid, newsid; 971 u16 tclass; 972 ssize_t length; 973 char *newcon = NULL; 974 u32 len; 975 976 length = task_has_security(current, SECURITY__COMPUTE_MEMBER); 977 if (length) 978 goto out; 979 980 length = -ENOMEM; 981 scon = kzalloc(size + 1, GFP_KERNEL); 982 if (!scon) 983 goto out; 984 985 length = -ENOMEM; 986 tcon = kzalloc(size + 1, GFP_KERNEL); 987 if (!tcon) 988 goto out; 989 990 length = -EINVAL; 991 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3) 992 goto out; 993 994 length = security_context_to_sid(scon, strlen(scon) + 1, &ssid); 995 if (length) 996 goto out; 997 998 length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid); 999 if (length) 1000 goto out; 1001 1002 length = security_member_sid(ssid, tsid, tclass, &newsid); 1003 if (length) 1004 goto out; 1005 1006 length = security_sid_to_context(newsid, &newcon, &len); 1007 if (length) 1008 goto out; 1009 1010 length = -ERANGE; 1011 if (len > SIMPLE_TRANSACTION_LIMIT) { 1012 printk(KERN_ERR "SELinux: %s: context size (%u) exceeds " 1013 "payload max\n", __func__, len); 1014 goto out; 1015 } 1016 1017 memcpy(buf, newcon, len); 1018 length = len; 1019 out: 1020 kfree(newcon); 1021 kfree(tcon); 1022 kfree(scon); 1023 return length; 1024 } 1025 1026 static struct inode *sel_make_inode(struct super_block *sb, int mode) 1027 { 1028 struct inode *ret = new_inode(sb); 1029 1030 if (ret) { 1031 ret->i_mode = mode; 1032 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME; 1033 } 1034 return ret; 1035 } 1036 1037 static ssize_t sel_read_bool(struct file *filep, char __user *buf, 1038 size_t count, loff_t *ppos) 1039 { 1040 char *page = NULL; 1041 ssize_t length; 1042 ssize_t ret; 1043 int cur_enforcing; 1044 struct inode *inode = filep->f_path.dentry->d_inode; 1045 unsigned index = inode->i_ino & SEL_INO_MASK; 1046 const char *name = filep->f_path.dentry->d_name.name; 1047 1048 mutex_lock(&sel_mutex); 1049 1050 ret = -EINVAL; 1051 if (index >= bool_num || strcmp(name, bool_pending_names[index])) 1052 goto out; 1053 1054 ret = -ENOMEM; 1055 page = (char *)get_zeroed_page(GFP_KERNEL); 1056 if (!page) 1057 goto out; 1058 1059 cur_enforcing = security_get_bool_value(index); 1060 if (cur_enforcing < 0) { 1061 ret = cur_enforcing; 1062 goto out; 1063 } 1064 length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing, 1065 bool_pending_values[index]); 1066 ret = simple_read_from_buffer(buf, count, ppos, page, length); 1067 out: 1068 mutex_unlock(&sel_mutex); 1069 free_page((unsigned long)page); 1070 return ret; 1071 } 1072 1073 static ssize_t sel_write_bool(struct file *filep, const char __user *buf, 1074 size_t count, loff_t *ppos) 1075 { 1076 char *page = NULL; 1077 ssize_t length; 1078 int new_value; 1079 struct inode *inode = filep->f_path.dentry->d_inode; 1080 unsigned index = inode->i_ino & SEL_INO_MASK; 1081 const char *name = filep->f_path.dentry->d_name.name; 1082 1083 mutex_lock(&sel_mutex); 1084 1085 length = task_has_security(current, SECURITY__SETBOOL); 1086 if (length) 1087 goto out; 1088 1089 length = -EINVAL; 1090 if (index >= bool_num || strcmp(name, bool_pending_names[index])) 1091 goto out; 1092 1093 length = -ENOMEM; 1094 if (count >= PAGE_SIZE) 1095 goto out; 1096 1097 /* No partial writes. */ 1098 length = -EINVAL; 1099 if (*ppos != 0) 1100 goto out; 1101 1102 length = -ENOMEM; 1103 page = (char *)get_zeroed_page(GFP_KERNEL); 1104 if (!page) 1105 goto out; 1106 1107 length = -EFAULT; 1108 if (copy_from_user(page, buf, count)) 1109 goto out; 1110 1111 length = -EINVAL; 1112 if (sscanf(page, "%d", &new_value) != 1) 1113 goto out; 1114 1115 if (new_value) 1116 new_value = 1; 1117 1118 bool_pending_values[index] = new_value; 1119 length = count; 1120 1121 out: 1122 mutex_unlock(&sel_mutex); 1123 free_page((unsigned long) page); 1124 return length; 1125 } 1126 1127 static const struct file_operations sel_bool_ops = { 1128 .read = sel_read_bool, 1129 .write = sel_write_bool, 1130 .llseek = generic_file_llseek, 1131 }; 1132 1133 static ssize_t sel_commit_bools_write(struct file *filep, 1134 const char __user *buf, 1135 size_t count, loff_t *ppos) 1136 { 1137 char *page = NULL; 1138 ssize_t length; 1139 int new_value; 1140 1141 mutex_lock(&sel_mutex); 1142 1143 length = task_has_security(current, SECURITY__SETBOOL); 1144 if (length) 1145 goto out; 1146 1147 length = -ENOMEM; 1148 if (count >= PAGE_SIZE) 1149 goto out; 1150 1151 /* No partial writes. */ 1152 length = -EINVAL; 1153 if (*ppos != 0) 1154 goto out; 1155 1156 length = -ENOMEM; 1157 page = (char *)get_zeroed_page(GFP_KERNEL); 1158 if (!page) 1159 goto out; 1160 1161 length = -EFAULT; 1162 if (copy_from_user(page, buf, count)) 1163 goto out; 1164 1165 length = -EINVAL; 1166 if (sscanf(page, "%d", &new_value) != 1) 1167 goto out; 1168 1169 length = 0; 1170 if (new_value && bool_pending_values) 1171 length = security_set_bools(bool_num, bool_pending_values); 1172 1173 if (!length) 1174 length = count; 1175 1176 out: 1177 mutex_unlock(&sel_mutex); 1178 free_page((unsigned long) page); 1179 return length; 1180 } 1181 1182 static const struct file_operations sel_commit_bools_ops = { 1183 .write = sel_commit_bools_write, 1184 .llseek = generic_file_llseek, 1185 }; 1186 1187 static void sel_remove_entries(struct dentry *de) 1188 { 1189 struct list_head *node; 1190 1191 spin_lock(&de->d_lock); 1192 node = de->d_subdirs.next; 1193 while (node != &de->d_subdirs) { 1194 struct dentry *d = list_entry(node, struct dentry, d_u.d_child); 1195 1196 spin_lock_nested(&d->d_lock, DENTRY_D_LOCK_NESTED); 1197 list_del_init(node); 1198 1199 if (d->d_inode) { 1200 dget_dlock(d); 1201 spin_unlock(&de->d_lock); 1202 spin_unlock(&d->d_lock); 1203 d_delete(d); 1204 simple_unlink(de->d_inode, d); 1205 dput(d); 1206 spin_lock(&de->d_lock); 1207 } else 1208 spin_unlock(&d->d_lock); 1209 node = de->d_subdirs.next; 1210 } 1211 1212 spin_unlock(&de->d_lock); 1213 } 1214 1215 #define BOOL_DIR_NAME "booleans" 1216 1217 static int sel_make_bools(void) 1218 { 1219 int i, ret; 1220 ssize_t len; 1221 struct dentry *dentry = NULL; 1222 struct dentry *dir = bool_dir; 1223 struct inode *inode = NULL; 1224 struct inode_security_struct *isec; 1225 char **names = NULL, *page; 1226 int num; 1227 int *values = NULL; 1228 u32 sid; 1229 1230 /* remove any existing files */ 1231 for (i = 0; i < bool_num; i++) 1232 kfree(bool_pending_names[i]); 1233 kfree(bool_pending_names); 1234 kfree(bool_pending_values); 1235 bool_pending_names = NULL; 1236 bool_pending_values = NULL; 1237 1238 sel_remove_entries(dir); 1239 1240 ret = -ENOMEM; 1241 page = (char *)get_zeroed_page(GFP_KERNEL); 1242 if (!page) 1243 goto out; 1244 1245 ret = security_get_bools(&num, &names, &values); 1246 if (ret) 1247 goto out; 1248 1249 for (i = 0; i < num; i++) { 1250 ret = -ENOMEM; 1251 dentry = d_alloc_name(dir, names[i]); 1252 if (!dentry) 1253 goto out; 1254 1255 ret = -ENOMEM; 1256 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR); 1257 if (!inode) 1258 goto out; 1259 1260 ret = -EINVAL; 1261 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]); 1262 if (len < 0) 1263 goto out; 1264 1265 ret = -ENAMETOOLONG; 1266 if (len >= PAGE_SIZE) 1267 goto out; 1268 1269 isec = (struct inode_security_struct *)inode->i_security; 1270 ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid); 1271 if (ret) 1272 goto out; 1273 1274 isec->sid = sid; 1275 isec->initialized = 1; 1276 inode->i_fop = &sel_bool_ops; 1277 inode->i_ino = i|SEL_BOOL_INO_OFFSET; 1278 d_add(dentry, inode); 1279 } 1280 bool_num = num; 1281 bool_pending_names = names; 1282 bool_pending_values = values; 1283 1284 free_page((unsigned long)page); 1285 return 0; 1286 out: 1287 free_page((unsigned long)page); 1288 1289 if (names) { 1290 for (i = 0; i < num; i++) 1291 kfree(names[i]); 1292 kfree(names); 1293 } 1294 kfree(values); 1295 sel_remove_entries(dir); 1296 1297 return ret; 1298 } 1299 1300 #define NULL_FILE_NAME "null" 1301 1302 struct dentry *selinux_null; 1303 1304 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf, 1305 size_t count, loff_t *ppos) 1306 { 1307 char tmpbuf[TMPBUFLEN]; 1308 ssize_t length; 1309 1310 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold); 1311 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1312 } 1313 1314 static ssize_t sel_write_avc_cache_threshold(struct file *file, 1315 const char __user *buf, 1316 size_t count, loff_t *ppos) 1317 1318 { 1319 char *page = NULL; 1320 ssize_t ret; 1321 int new_value; 1322 1323 ret = task_has_security(current, SECURITY__SETSECPARAM); 1324 if (ret) 1325 goto out; 1326 1327 ret = -ENOMEM; 1328 if (count >= PAGE_SIZE) 1329 goto out; 1330 1331 /* No partial writes. */ 1332 ret = -EINVAL; 1333 if (*ppos != 0) 1334 goto out; 1335 1336 ret = -ENOMEM; 1337 page = (char *)get_zeroed_page(GFP_KERNEL); 1338 if (!page) 1339 goto out; 1340 1341 ret = -EFAULT; 1342 if (copy_from_user(page, buf, count)) 1343 goto out; 1344 1345 ret = -EINVAL; 1346 if (sscanf(page, "%u", &new_value) != 1) 1347 goto out; 1348 1349 avc_cache_threshold = new_value; 1350 1351 ret = count; 1352 out: 1353 free_page((unsigned long)page); 1354 return ret; 1355 } 1356 1357 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf, 1358 size_t count, loff_t *ppos) 1359 { 1360 char *page; 1361 ssize_t length; 1362 1363 page = (char *)__get_free_page(GFP_KERNEL); 1364 if (!page) 1365 return -ENOMEM; 1366 1367 length = avc_get_hash_stats(page); 1368 if (length >= 0) 1369 length = simple_read_from_buffer(buf, count, ppos, page, length); 1370 free_page((unsigned long)page); 1371 1372 return length; 1373 } 1374 1375 static const struct file_operations sel_avc_cache_threshold_ops = { 1376 .read = sel_read_avc_cache_threshold, 1377 .write = sel_write_avc_cache_threshold, 1378 .llseek = generic_file_llseek, 1379 }; 1380 1381 static const struct file_operations sel_avc_hash_stats_ops = { 1382 .read = sel_read_avc_hash_stats, 1383 .llseek = generic_file_llseek, 1384 }; 1385 1386 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS 1387 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx) 1388 { 1389 int cpu; 1390 1391 for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) { 1392 if (!cpu_possible(cpu)) 1393 continue; 1394 *idx = cpu + 1; 1395 return &per_cpu(avc_cache_stats, cpu); 1396 } 1397 return NULL; 1398 } 1399 1400 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos) 1401 { 1402 loff_t n = *pos - 1; 1403 1404 if (*pos == 0) 1405 return SEQ_START_TOKEN; 1406 1407 return sel_avc_get_stat_idx(&n); 1408 } 1409 1410 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos) 1411 { 1412 return sel_avc_get_stat_idx(pos); 1413 } 1414 1415 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v) 1416 { 1417 struct avc_cache_stats *st = v; 1418 1419 if (v == SEQ_START_TOKEN) 1420 seq_printf(seq, "lookups hits misses allocations reclaims " 1421 "frees\n"); 1422 else { 1423 unsigned int lookups = st->lookups; 1424 unsigned int misses = st->misses; 1425 unsigned int hits = lookups - misses; 1426 seq_printf(seq, "%u %u %u %u %u %u\n", lookups, 1427 hits, misses, st->allocations, 1428 st->reclaims, st->frees); 1429 } 1430 return 0; 1431 } 1432 1433 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v) 1434 { } 1435 1436 static const struct seq_operations sel_avc_cache_stats_seq_ops = { 1437 .start = sel_avc_stats_seq_start, 1438 .next = sel_avc_stats_seq_next, 1439 .show = sel_avc_stats_seq_show, 1440 .stop = sel_avc_stats_seq_stop, 1441 }; 1442 1443 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file) 1444 { 1445 return seq_open(file, &sel_avc_cache_stats_seq_ops); 1446 } 1447 1448 static const struct file_operations sel_avc_cache_stats_ops = { 1449 .open = sel_open_avc_cache_stats, 1450 .read = seq_read, 1451 .llseek = seq_lseek, 1452 .release = seq_release, 1453 }; 1454 #endif 1455 1456 static int sel_make_avc_files(struct dentry *dir) 1457 { 1458 int i; 1459 static struct tree_descr files[] = { 1460 { "cache_threshold", 1461 &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR }, 1462 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO }, 1463 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS 1464 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO }, 1465 #endif 1466 }; 1467 1468 for (i = 0; i < ARRAY_SIZE(files); i++) { 1469 struct inode *inode; 1470 struct dentry *dentry; 1471 1472 dentry = d_alloc_name(dir, files[i].name); 1473 if (!dentry) 1474 return -ENOMEM; 1475 1476 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode); 1477 if (!inode) 1478 return -ENOMEM; 1479 1480 inode->i_fop = files[i].ops; 1481 inode->i_ino = ++sel_last_ino; 1482 d_add(dentry, inode); 1483 } 1484 1485 return 0; 1486 } 1487 1488 static ssize_t sel_read_initcon(struct file *file, char __user *buf, 1489 size_t count, loff_t *ppos) 1490 { 1491 struct inode *inode; 1492 char *con; 1493 u32 sid, len; 1494 ssize_t ret; 1495 1496 inode = file->f_path.dentry->d_inode; 1497 sid = inode->i_ino&SEL_INO_MASK; 1498 ret = security_sid_to_context(sid, &con, &len); 1499 if (ret) 1500 return ret; 1501 1502 ret = simple_read_from_buffer(buf, count, ppos, con, len); 1503 kfree(con); 1504 return ret; 1505 } 1506 1507 static const struct file_operations sel_initcon_ops = { 1508 .read = sel_read_initcon, 1509 .llseek = generic_file_llseek, 1510 }; 1511 1512 static int sel_make_initcon_files(struct dentry *dir) 1513 { 1514 int i; 1515 1516 for (i = 1; i <= SECINITSID_NUM; i++) { 1517 struct inode *inode; 1518 struct dentry *dentry; 1519 dentry = d_alloc_name(dir, security_get_initial_sid_context(i)); 1520 if (!dentry) 1521 return -ENOMEM; 1522 1523 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO); 1524 if (!inode) 1525 return -ENOMEM; 1526 1527 inode->i_fop = &sel_initcon_ops; 1528 inode->i_ino = i|SEL_INITCON_INO_OFFSET; 1529 d_add(dentry, inode); 1530 } 1531 1532 return 0; 1533 } 1534 1535 static inline unsigned int sel_div(unsigned long a, unsigned long b) 1536 { 1537 return a / b - (a % b < 0); 1538 } 1539 1540 static inline unsigned long sel_class_to_ino(u16 class) 1541 { 1542 return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET; 1543 } 1544 1545 static inline u16 sel_ino_to_class(unsigned long ino) 1546 { 1547 return sel_div(ino & SEL_INO_MASK, SEL_VEC_MAX + 1); 1548 } 1549 1550 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm) 1551 { 1552 return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET; 1553 } 1554 1555 static inline u32 sel_ino_to_perm(unsigned long ino) 1556 { 1557 return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1); 1558 } 1559 1560 static ssize_t sel_read_class(struct file *file, char __user *buf, 1561 size_t count, loff_t *ppos) 1562 { 1563 ssize_t rc, len; 1564 char *page; 1565 unsigned long ino = file->f_path.dentry->d_inode->i_ino; 1566 1567 page = (char *)__get_free_page(GFP_KERNEL); 1568 if (!page) 1569 return -ENOMEM; 1570 1571 len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_class(ino)); 1572 rc = simple_read_from_buffer(buf, count, ppos, page, len); 1573 free_page((unsigned long)page); 1574 1575 return rc; 1576 } 1577 1578 static const struct file_operations sel_class_ops = { 1579 .read = sel_read_class, 1580 .llseek = generic_file_llseek, 1581 }; 1582 1583 static ssize_t sel_read_perm(struct file *file, char __user *buf, 1584 size_t count, loff_t *ppos) 1585 { 1586 ssize_t rc, len; 1587 char *page; 1588 unsigned long ino = file->f_path.dentry->d_inode->i_ino; 1589 1590 page = (char *)__get_free_page(GFP_KERNEL); 1591 if (!page) 1592 return -ENOMEM; 1593 1594 len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_perm(ino)); 1595 rc = simple_read_from_buffer(buf, count, ppos, page, len); 1596 free_page((unsigned long)page); 1597 1598 return rc; 1599 } 1600 1601 static const struct file_operations sel_perm_ops = { 1602 .read = sel_read_perm, 1603 .llseek = generic_file_llseek, 1604 }; 1605 1606 static ssize_t sel_read_policycap(struct file *file, char __user *buf, 1607 size_t count, loff_t *ppos) 1608 { 1609 int value; 1610 char tmpbuf[TMPBUFLEN]; 1611 ssize_t length; 1612 unsigned long i_ino = file->f_path.dentry->d_inode->i_ino; 1613 1614 value = security_policycap_supported(i_ino & SEL_INO_MASK); 1615 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value); 1616 1617 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1618 } 1619 1620 static const struct file_operations sel_policycap_ops = { 1621 .read = sel_read_policycap, 1622 .llseek = generic_file_llseek, 1623 }; 1624 1625 static int sel_make_perm_files(char *objclass, int classvalue, 1626 struct dentry *dir) 1627 { 1628 int i, rc, nperms; 1629 char **perms; 1630 1631 rc = security_get_permissions(objclass, &perms, &nperms); 1632 if (rc) 1633 return rc; 1634 1635 for (i = 0; i < nperms; i++) { 1636 struct inode *inode; 1637 struct dentry *dentry; 1638 1639 rc = -ENOMEM; 1640 dentry = d_alloc_name(dir, perms[i]); 1641 if (!dentry) 1642 goto out; 1643 1644 rc = -ENOMEM; 1645 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO); 1646 if (!inode) 1647 goto out; 1648 1649 inode->i_fop = &sel_perm_ops; 1650 /* i+1 since perm values are 1-indexed */ 1651 inode->i_ino = sel_perm_to_ino(classvalue, i + 1); 1652 d_add(dentry, inode); 1653 } 1654 rc = 0; 1655 out: 1656 for (i = 0; i < nperms; i++) 1657 kfree(perms[i]); 1658 kfree(perms); 1659 return rc; 1660 } 1661 1662 static int sel_make_class_dir_entries(char *classname, int index, 1663 struct dentry *dir) 1664 { 1665 struct dentry *dentry = NULL; 1666 struct inode *inode = NULL; 1667 int rc; 1668 1669 dentry = d_alloc_name(dir, "index"); 1670 if (!dentry) 1671 return -ENOMEM; 1672 1673 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO); 1674 if (!inode) 1675 return -ENOMEM; 1676 1677 inode->i_fop = &sel_class_ops; 1678 inode->i_ino = sel_class_to_ino(index); 1679 d_add(dentry, inode); 1680 1681 dentry = sel_make_dir(dir, "perms", &last_class_ino); 1682 if (IS_ERR(dentry)) 1683 return PTR_ERR(dentry); 1684 1685 rc = sel_make_perm_files(classname, index, dentry); 1686 1687 return rc; 1688 } 1689 1690 static void sel_remove_classes(void) 1691 { 1692 struct list_head *class_node; 1693 1694 list_for_each(class_node, &class_dir->d_subdirs) { 1695 struct dentry *class_subdir = list_entry(class_node, 1696 struct dentry, d_u.d_child); 1697 struct list_head *class_subdir_node; 1698 1699 list_for_each(class_subdir_node, &class_subdir->d_subdirs) { 1700 struct dentry *d = list_entry(class_subdir_node, 1701 struct dentry, d_u.d_child); 1702 1703 if (d->d_inode) 1704 if (d->d_inode->i_mode & S_IFDIR) 1705 sel_remove_entries(d); 1706 } 1707 1708 sel_remove_entries(class_subdir); 1709 } 1710 1711 sel_remove_entries(class_dir); 1712 } 1713 1714 static int sel_make_classes(void) 1715 { 1716 int rc, nclasses, i; 1717 char **classes; 1718 1719 /* delete any existing entries */ 1720 sel_remove_classes(); 1721 1722 rc = security_get_classes(&classes, &nclasses); 1723 if (rc) 1724 return rc; 1725 1726 /* +2 since classes are 1-indexed */ 1727 last_class_ino = sel_class_to_ino(nclasses + 2); 1728 1729 for (i = 0; i < nclasses; i++) { 1730 struct dentry *class_name_dir; 1731 1732 class_name_dir = sel_make_dir(class_dir, classes[i], 1733 &last_class_ino); 1734 if (IS_ERR(class_name_dir)) { 1735 rc = PTR_ERR(class_name_dir); 1736 goto out; 1737 } 1738 1739 /* i+1 since class values are 1-indexed */ 1740 rc = sel_make_class_dir_entries(classes[i], i + 1, 1741 class_name_dir); 1742 if (rc) 1743 goto out; 1744 } 1745 rc = 0; 1746 out: 1747 for (i = 0; i < nclasses; i++) 1748 kfree(classes[i]); 1749 kfree(classes); 1750 return rc; 1751 } 1752 1753 static int sel_make_policycap(void) 1754 { 1755 unsigned int iter; 1756 struct dentry *dentry = NULL; 1757 struct inode *inode = NULL; 1758 1759 sel_remove_entries(policycap_dir); 1760 1761 for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) { 1762 if (iter < ARRAY_SIZE(policycap_names)) 1763 dentry = d_alloc_name(policycap_dir, 1764 policycap_names[iter]); 1765 else 1766 dentry = d_alloc_name(policycap_dir, "unknown"); 1767 1768 if (dentry == NULL) 1769 return -ENOMEM; 1770 1771 inode = sel_make_inode(policycap_dir->d_sb, S_IFREG | S_IRUGO); 1772 if (inode == NULL) 1773 return -ENOMEM; 1774 1775 inode->i_fop = &sel_policycap_ops; 1776 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET; 1777 d_add(dentry, inode); 1778 } 1779 1780 return 0; 1781 } 1782 1783 static struct dentry *sel_make_dir(struct dentry *dir, const char *name, 1784 unsigned long *ino) 1785 { 1786 struct dentry *dentry = d_alloc_name(dir, name); 1787 struct inode *inode; 1788 1789 if (!dentry) 1790 return ERR_PTR(-ENOMEM); 1791 1792 inode = sel_make_inode(dir->d_sb, S_IFDIR | S_IRUGO | S_IXUGO); 1793 if (!inode) { 1794 dput(dentry); 1795 return ERR_PTR(-ENOMEM); 1796 } 1797 1798 inode->i_op = &simple_dir_inode_operations; 1799 inode->i_fop = &simple_dir_operations; 1800 inode->i_ino = ++(*ino); 1801 /* directory inodes start off with i_nlink == 2 (for "." entry) */ 1802 inc_nlink(inode); 1803 d_add(dentry, inode); 1804 /* bump link count on parent directory, too */ 1805 inc_nlink(dir->d_inode); 1806 1807 return dentry; 1808 } 1809 1810 static int sel_fill_super(struct super_block *sb, void *data, int silent) 1811 { 1812 int ret; 1813 struct dentry *dentry; 1814 struct inode *inode; 1815 struct inode_security_struct *isec; 1816 1817 static struct tree_descr selinux_files[] = { 1818 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR}, 1819 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR}, 1820 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO}, 1821 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO}, 1822 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO}, 1823 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO}, 1824 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO}, 1825 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO}, 1826 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR}, 1827 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO}, 1828 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR}, 1829 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO}, 1830 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR}, 1831 [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO}, 1832 [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO}, 1833 [SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO}, 1834 [SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUSR}, 1835 /* last one */ {""} 1836 }; 1837 ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files); 1838 if (ret) 1839 goto err; 1840 1841 bool_dir = sel_make_dir(sb->s_root, BOOL_DIR_NAME, &sel_last_ino); 1842 if (IS_ERR(bool_dir)) { 1843 ret = PTR_ERR(bool_dir); 1844 bool_dir = NULL; 1845 goto err; 1846 } 1847 1848 ret = -ENOMEM; 1849 dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME); 1850 if (!dentry) 1851 goto err; 1852 1853 ret = -ENOMEM; 1854 inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO); 1855 if (!inode) 1856 goto err; 1857 1858 inode->i_ino = ++sel_last_ino; 1859 isec = (struct inode_security_struct *)inode->i_security; 1860 isec->sid = SECINITSID_DEVNULL; 1861 isec->sclass = SECCLASS_CHR_FILE; 1862 isec->initialized = 1; 1863 1864 init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3)); 1865 d_add(dentry, inode); 1866 selinux_null = dentry; 1867 1868 dentry = sel_make_dir(sb->s_root, "avc", &sel_last_ino); 1869 if (IS_ERR(dentry)) { 1870 ret = PTR_ERR(dentry); 1871 goto err; 1872 } 1873 1874 ret = sel_make_avc_files(dentry); 1875 if (ret) 1876 goto err; 1877 1878 dentry = sel_make_dir(sb->s_root, "initial_contexts", &sel_last_ino); 1879 if (IS_ERR(dentry)) { 1880 ret = PTR_ERR(dentry); 1881 goto err; 1882 } 1883 1884 ret = sel_make_initcon_files(dentry); 1885 if (ret) 1886 goto err; 1887 1888 class_dir = sel_make_dir(sb->s_root, "class", &sel_last_ino); 1889 if (IS_ERR(class_dir)) { 1890 ret = PTR_ERR(class_dir); 1891 class_dir = NULL; 1892 goto err; 1893 } 1894 1895 policycap_dir = sel_make_dir(sb->s_root, "policy_capabilities", &sel_last_ino); 1896 if (IS_ERR(policycap_dir)) { 1897 ret = PTR_ERR(policycap_dir); 1898 policycap_dir = NULL; 1899 goto err; 1900 } 1901 return 0; 1902 err: 1903 printk(KERN_ERR "SELinux: %s: failed while creating inodes\n", 1904 __func__); 1905 return ret; 1906 } 1907 1908 static struct dentry *sel_mount(struct file_system_type *fs_type, 1909 int flags, const char *dev_name, void *data) 1910 { 1911 return mount_single(fs_type, flags, data, sel_fill_super); 1912 } 1913 1914 static struct file_system_type sel_fs_type = { 1915 .name = "selinuxfs", 1916 .mount = sel_mount, 1917 .kill_sb = kill_litter_super, 1918 }; 1919 1920 struct vfsmount *selinuxfs_mount; 1921 static struct kobject *selinuxfs_kobj; 1922 1923 static int __init init_sel_fs(void) 1924 { 1925 int err; 1926 1927 if (!selinux_enabled) 1928 return 0; 1929 1930 selinuxfs_kobj = kobject_create_and_add("selinux", fs_kobj); 1931 if (!selinuxfs_kobj) 1932 return -ENOMEM; 1933 1934 err = register_filesystem(&sel_fs_type); 1935 if (err) { 1936 kobject_put(selinuxfs_kobj); 1937 return err; 1938 } 1939 1940 selinuxfs_mount = kern_mount(&sel_fs_type); 1941 if (IS_ERR(selinuxfs_mount)) { 1942 printk(KERN_ERR "selinuxfs: could not mount!\n"); 1943 err = PTR_ERR(selinuxfs_mount); 1944 selinuxfs_mount = NULL; 1945 } 1946 1947 return err; 1948 } 1949 1950 __initcall(init_sel_fs); 1951 1952 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 1953 void exit_sel_fs(void) 1954 { 1955 kobject_put(selinuxfs_kobj); 1956 kern_unmount(selinuxfs_mount); 1957 unregister_filesystem(&sel_fs_type); 1958 } 1959 #endif 1960