1 /* Updated: Karl MacMillan <kmacmillan@tresys.com> 2 * 3 * Added conditional policy language extensions 4 * 5 * Updated: Hewlett-Packard <paul@paul-moore.com> 6 * 7 * Added support for the policy capability bitmap 8 * 9 * Copyright (C) 2007 Hewlett-Packard Development Company, L.P. 10 * Copyright (C) 2003 - 2004 Tresys Technology, LLC 11 * Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com> 12 * This program is free software; you can redistribute it and/or modify 13 * it under the terms of the GNU General Public License as published by 14 * the Free Software Foundation, version 2. 15 */ 16 17 #include <linux/kernel.h> 18 #include <linux/pagemap.h> 19 #include <linux/slab.h> 20 #include <linux/vmalloc.h> 21 #include <linux/fs.h> 22 #include <linux/mutex.h> 23 #include <linux/init.h> 24 #include <linux/string.h> 25 #include <linux/security.h> 26 #include <linux/major.h> 27 #include <linux/seq_file.h> 28 #include <linux/percpu.h> 29 #include <linux/audit.h> 30 #include <linux/uaccess.h> 31 #include <linux/kobject.h> 32 #include <linux/ctype.h> 33 34 /* selinuxfs pseudo filesystem for exporting the security policy API. 35 Based on the proc code and the fs/nfsd/nfsctl.c code. */ 36 37 #include "flask.h" 38 #include "avc.h" 39 #include "avc_ss.h" 40 #include "security.h" 41 #include "objsec.h" 42 #include "conditional.h" 43 44 /* Policy capability filenames */ 45 static char *policycap_names[] = { 46 "network_peer_controls", 47 "open_perms", 48 "redhat1", 49 "always_check_network" 50 }; 51 52 unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE; 53 54 static int __init checkreqprot_setup(char *str) 55 { 56 unsigned long checkreqprot; 57 if (!kstrtoul(str, 0, &checkreqprot)) 58 selinux_checkreqprot = checkreqprot ? 1 : 0; 59 return 1; 60 } 61 __setup("checkreqprot=", checkreqprot_setup); 62 63 static DEFINE_MUTEX(sel_mutex); 64 65 /* global data for booleans */ 66 static struct dentry *bool_dir; 67 static int bool_num; 68 static char **bool_pending_names; 69 static int *bool_pending_values; 70 71 /* global data for classes */ 72 static struct dentry *class_dir; 73 static unsigned long last_class_ino; 74 75 static char policy_opened; 76 77 /* global data for policy capabilities */ 78 static struct dentry *policycap_dir; 79 80 /* Check whether a task is allowed to use a security operation. */ 81 static int task_has_security(struct task_struct *tsk, 82 u32 perms) 83 { 84 const struct task_security_struct *tsec; 85 u32 sid = 0; 86 87 rcu_read_lock(); 88 tsec = __task_cred(tsk)->security; 89 if (tsec) 90 sid = tsec->sid; 91 rcu_read_unlock(); 92 if (!tsec) 93 return -EACCES; 94 95 return avc_has_perm(sid, SECINITSID_SECURITY, 96 SECCLASS_SECURITY, perms, NULL); 97 } 98 99 enum sel_inos { 100 SEL_ROOT_INO = 2, 101 SEL_LOAD, /* load policy */ 102 SEL_ENFORCE, /* get or set enforcing status */ 103 SEL_CONTEXT, /* validate context */ 104 SEL_ACCESS, /* compute access decision */ 105 SEL_CREATE, /* compute create labeling decision */ 106 SEL_RELABEL, /* compute relabeling decision */ 107 SEL_USER, /* compute reachable user contexts */ 108 SEL_POLICYVERS, /* return policy version for this kernel */ 109 SEL_COMMIT_BOOLS, /* commit new boolean values */ 110 SEL_MLS, /* return if MLS policy is enabled */ 111 SEL_DISABLE, /* disable SELinux until next reboot */ 112 SEL_MEMBER, /* compute polyinstantiation membership decision */ 113 SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */ 114 SEL_COMPAT_NET, /* whether to use old compat network packet controls */ 115 SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */ 116 SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */ 117 SEL_STATUS, /* export current status using mmap() */ 118 SEL_POLICY, /* allow userspace to read the in kernel policy */ 119 SEL_INO_NEXT, /* The next inode number to use */ 120 }; 121 122 static unsigned long sel_last_ino = SEL_INO_NEXT - 1; 123 124 #define SEL_INITCON_INO_OFFSET 0x01000000 125 #define SEL_BOOL_INO_OFFSET 0x02000000 126 #define SEL_CLASS_INO_OFFSET 0x04000000 127 #define SEL_POLICYCAP_INO_OFFSET 0x08000000 128 #define SEL_INO_MASK 0x00ffffff 129 130 #define TMPBUFLEN 12 131 static ssize_t sel_read_enforce(struct file *filp, char __user *buf, 132 size_t count, loff_t *ppos) 133 { 134 char tmpbuf[TMPBUFLEN]; 135 ssize_t length; 136 137 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing); 138 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 139 } 140 141 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 142 static ssize_t sel_write_enforce(struct file *file, const char __user *buf, 143 size_t count, loff_t *ppos) 144 145 { 146 char *page = NULL; 147 ssize_t length; 148 int new_value; 149 150 length = -ENOMEM; 151 if (count >= PAGE_SIZE) 152 goto out; 153 154 /* No partial writes. */ 155 length = -EINVAL; 156 if (*ppos != 0) 157 goto out; 158 159 length = -ENOMEM; 160 page = (char *)get_zeroed_page(GFP_KERNEL); 161 if (!page) 162 goto out; 163 164 length = -EFAULT; 165 if (copy_from_user(page, buf, count)) 166 goto out; 167 168 length = -EINVAL; 169 if (sscanf(page, "%d", &new_value) != 1) 170 goto out; 171 172 if (new_value != selinux_enforcing) { 173 length = task_has_security(current, SECURITY__SETENFORCE); 174 if (length) 175 goto out; 176 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS, 177 "enforcing=%d old_enforcing=%d auid=%u ses=%u", 178 new_value, selinux_enforcing, 179 from_kuid(&init_user_ns, audit_get_loginuid(current)), 180 audit_get_sessionid(current)); 181 selinux_enforcing = new_value; 182 if (selinux_enforcing) 183 avc_ss_reset(0); 184 selnl_notify_setenforce(selinux_enforcing); 185 selinux_status_update_setenforce(selinux_enforcing); 186 } 187 length = count; 188 out: 189 free_page((unsigned long) page); 190 return length; 191 } 192 #else 193 #define sel_write_enforce NULL 194 #endif 195 196 static const struct file_operations sel_enforce_ops = { 197 .read = sel_read_enforce, 198 .write = sel_write_enforce, 199 .llseek = generic_file_llseek, 200 }; 201 202 static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf, 203 size_t count, loff_t *ppos) 204 { 205 char tmpbuf[TMPBUFLEN]; 206 ssize_t length; 207 ino_t ino = file_inode(filp)->i_ino; 208 int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ? 209 security_get_reject_unknown() : !security_get_allow_unknown(); 210 211 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown); 212 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 213 } 214 215 static const struct file_operations sel_handle_unknown_ops = { 216 .read = sel_read_handle_unknown, 217 .llseek = generic_file_llseek, 218 }; 219 220 static int sel_open_handle_status(struct inode *inode, struct file *filp) 221 { 222 struct page *status = selinux_kernel_status_page(); 223 224 if (!status) 225 return -ENOMEM; 226 227 filp->private_data = status; 228 229 return 0; 230 } 231 232 static ssize_t sel_read_handle_status(struct file *filp, char __user *buf, 233 size_t count, loff_t *ppos) 234 { 235 struct page *status = filp->private_data; 236 237 BUG_ON(!status); 238 239 return simple_read_from_buffer(buf, count, ppos, 240 page_address(status), 241 sizeof(struct selinux_kernel_status)); 242 } 243 244 static int sel_mmap_handle_status(struct file *filp, 245 struct vm_area_struct *vma) 246 { 247 struct page *status = filp->private_data; 248 unsigned long size = vma->vm_end - vma->vm_start; 249 250 BUG_ON(!status); 251 252 /* only allows one page from the head */ 253 if (vma->vm_pgoff > 0 || size != PAGE_SIZE) 254 return -EIO; 255 /* disallow writable mapping */ 256 if (vma->vm_flags & VM_WRITE) 257 return -EPERM; 258 /* disallow mprotect() turns it into writable */ 259 vma->vm_flags &= ~VM_MAYWRITE; 260 261 return remap_pfn_range(vma, vma->vm_start, 262 page_to_pfn(status), 263 size, vma->vm_page_prot); 264 } 265 266 static const struct file_operations sel_handle_status_ops = { 267 .open = sel_open_handle_status, 268 .read = sel_read_handle_status, 269 .mmap = sel_mmap_handle_status, 270 .llseek = generic_file_llseek, 271 }; 272 273 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 274 static ssize_t sel_write_disable(struct file *file, const char __user *buf, 275 size_t count, loff_t *ppos) 276 277 { 278 char *page = NULL; 279 ssize_t length; 280 int new_value; 281 282 length = -ENOMEM; 283 if (count >= PAGE_SIZE) 284 goto out; 285 286 /* No partial writes. */ 287 length = -EINVAL; 288 if (*ppos != 0) 289 goto out; 290 291 length = -ENOMEM; 292 page = (char *)get_zeroed_page(GFP_KERNEL); 293 if (!page) 294 goto out; 295 296 length = -EFAULT; 297 if (copy_from_user(page, buf, count)) 298 goto out; 299 300 length = -EINVAL; 301 if (sscanf(page, "%d", &new_value) != 1) 302 goto out; 303 304 if (new_value) { 305 length = selinux_disable(); 306 if (length) 307 goto out; 308 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS, 309 "selinux=0 auid=%u ses=%u", 310 from_kuid(&init_user_ns, audit_get_loginuid(current)), 311 audit_get_sessionid(current)); 312 } 313 314 length = count; 315 out: 316 free_page((unsigned long) page); 317 return length; 318 } 319 #else 320 #define sel_write_disable NULL 321 #endif 322 323 static const struct file_operations sel_disable_ops = { 324 .write = sel_write_disable, 325 .llseek = generic_file_llseek, 326 }; 327 328 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf, 329 size_t count, loff_t *ppos) 330 { 331 char tmpbuf[TMPBUFLEN]; 332 ssize_t length; 333 334 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX); 335 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 336 } 337 338 static const struct file_operations sel_policyvers_ops = { 339 .read = sel_read_policyvers, 340 .llseek = generic_file_llseek, 341 }; 342 343 /* declaration for sel_write_load */ 344 static int sel_make_bools(void); 345 static int sel_make_classes(void); 346 static int sel_make_policycap(void); 347 348 /* declaration for sel_make_class_dirs */ 349 static struct dentry *sel_make_dir(struct dentry *dir, const char *name, 350 unsigned long *ino); 351 352 static ssize_t sel_read_mls(struct file *filp, char __user *buf, 353 size_t count, loff_t *ppos) 354 { 355 char tmpbuf[TMPBUFLEN]; 356 ssize_t length; 357 358 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", 359 security_mls_enabled()); 360 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 361 } 362 363 static const struct file_operations sel_mls_ops = { 364 .read = sel_read_mls, 365 .llseek = generic_file_llseek, 366 }; 367 368 struct policy_load_memory { 369 size_t len; 370 void *data; 371 }; 372 373 static int sel_open_policy(struct inode *inode, struct file *filp) 374 { 375 struct policy_load_memory *plm = NULL; 376 int rc; 377 378 BUG_ON(filp->private_data); 379 380 mutex_lock(&sel_mutex); 381 382 rc = task_has_security(current, SECURITY__READ_POLICY); 383 if (rc) 384 goto err; 385 386 rc = -EBUSY; 387 if (policy_opened) 388 goto err; 389 390 rc = -ENOMEM; 391 plm = kzalloc(sizeof(*plm), GFP_KERNEL); 392 if (!plm) 393 goto err; 394 395 if (i_size_read(inode) != security_policydb_len()) { 396 mutex_lock(&inode->i_mutex); 397 i_size_write(inode, security_policydb_len()); 398 mutex_unlock(&inode->i_mutex); 399 } 400 401 rc = security_read_policy(&plm->data, &plm->len); 402 if (rc) 403 goto err; 404 405 policy_opened = 1; 406 407 filp->private_data = plm; 408 409 mutex_unlock(&sel_mutex); 410 411 return 0; 412 err: 413 mutex_unlock(&sel_mutex); 414 415 if (plm) 416 vfree(plm->data); 417 kfree(plm); 418 return rc; 419 } 420 421 static int sel_release_policy(struct inode *inode, struct file *filp) 422 { 423 struct policy_load_memory *plm = filp->private_data; 424 425 BUG_ON(!plm); 426 427 policy_opened = 0; 428 429 vfree(plm->data); 430 kfree(plm); 431 432 return 0; 433 } 434 435 static ssize_t sel_read_policy(struct file *filp, char __user *buf, 436 size_t count, loff_t *ppos) 437 { 438 struct policy_load_memory *plm = filp->private_data; 439 int ret; 440 441 mutex_lock(&sel_mutex); 442 443 ret = task_has_security(current, SECURITY__READ_POLICY); 444 if (ret) 445 goto out; 446 447 ret = simple_read_from_buffer(buf, count, ppos, plm->data, plm->len); 448 out: 449 mutex_unlock(&sel_mutex); 450 return ret; 451 } 452 453 static int sel_mmap_policy_fault(struct vm_area_struct *vma, 454 struct vm_fault *vmf) 455 { 456 struct policy_load_memory *plm = vma->vm_file->private_data; 457 unsigned long offset; 458 struct page *page; 459 460 if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE)) 461 return VM_FAULT_SIGBUS; 462 463 offset = vmf->pgoff << PAGE_SHIFT; 464 if (offset >= roundup(plm->len, PAGE_SIZE)) 465 return VM_FAULT_SIGBUS; 466 467 page = vmalloc_to_page(plm->data + offset); 468 get_page(page); 469 470 vmf->page = page; 471 472 return 0; 473 } 474 475 static struct vm_operations_struct sel_mmap_policy_ops = { 476 .fault = sel_mmap_policy_fault, 477 .page_mkwrite = sel_mmap_policy_fault, 478 }; 479 480 static int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma) 481 { 482 if (vma->vm_flags & VM_SHARED) { 483 /* do not allow mprotect to make mapping writable */ 484 vma->vm_flags &= ~VM_MAYWRITE; 485 486 if (vma->vm_flags & VM_WRITE) 487 return -EACCES; 488 } 489 490 vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP; 491 vma->vm_ops = &sel_mmap_policy_ops; 492 493 return 0; 494 } 495 496 static const struct file_operations sel_policy_ops = { 497 .open = sel_open_policy, 498 .read = sel_read_policy, 499 .mmap = sel_mmap_policy, 500 .release = sel_release_policy, 501 .llseek = generic_file_llseek, 502 }; 503 504 static ssize_t sel_write_load(struct file *file, const char __user *buf, 505 size_t count, loff_t *ppos) 506 507 { 508 ssize_t length; 509 void *data = NULL; 510 511 mutex_lock(&sel_mutex); 512 513 length = task_has_security(current, SECURITY__LOAD_POLICY); 514 if (length) 515 goto out; 516 517 /* No partial writes. */ 518 length = -EINVAL; 519 if (*ppos != 0) 520 goto out; 521 522 length = -EFBIG; 523 if (count > 64 * 1024 * 1024) 524 goto out; 525 526 length = -ENOMEM; 527 data = vmalloc(count); 528 if (!data) 529 goto out; 530 531 length = -EFAULT; 532 if (copy_from_user(data, buf, count) != 0) 533 goto out; 534 535 length = security_load_policy(data, count); 536 if (length) 537 goto out; 538 539 length = sel_make_bools(); 540 if (length) 541 goto out1; 542 543 length = sel_make_classes(); 544 if (length) 545 goto out1; 546 547 length = sel_make_policycap(); 548 if (length) 549 goto out1; 550 551 length = count; 552 553 out1: 554 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD, 555 "policy loaded auid=%u ses=%u", 556 from_kuid(&init_user_ns, audit_get_loginuid(current)), 557 audit_get_sessionid(current)); 558 out: 559 mutex_unlock(&sel_mutex); 560 vfree(data); 561 return length; 562 } 563 564 static const struct file_operations sel_load_ops = { 565 .write = sel_write_load, 566 .llseek = generic_file_llseek, 567 }; 568 569 static ssize_t sel_write_context(struct file *file, char *buf, size_t size) 570 { 571 char *canon = NULL; 572 u32 sid, len; 573 ssize_t length; 574 575 length = task_has_security(current, SECURITY__CHECK_CONTEXT); 576 if (length) 577 goto out; 578 579 length = security_context_to_sid(buf, size, &sid, GFP_KERNEL); 580 if (length) 581 goto out; 582 583 length = security_sid_to_context(sid, &canon, &len); 584 if (length) 585 goto out; 586 587 length = -ERANGE; 588 if (len > SIMPLE_TRANSACTION_LIMIT) { 589 printk(KERN_ERR "SELinux: %s: context size (%u) exceeds " 590 "payload max\n", __func__, len); 591 goto out; 592 } 593 594 memcpy(buf, canon, len); 595 length = len; 596 out: 597 kfree(canon); 598 return length; 599 } 600 601 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf, 602 size_t count, loff_t *ppos) 603 { 604 char tmpbuf[TMPBUFLEN]; 605 ssize_t length; 606 607 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot); 608 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 609 } 610 611 static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf, 612 size_t count, loff_t *ppos) 613 { 614 char *page = NULL; 615 ssize_t length; 616 unsigned int new_value; 617 618 length = task_has_security(current, SECURITY__SETCHECKREQPROT); 619 if (length) 620 goto out; 621 622 length = -ENOMEM; 623 if (count >= PAGE_SIZE) 624 goto out; 625 626 /* No partial writes. */ 627 length = -EINVAL; 628 if (*ppos != 0) 629 goto out; 630 631 length = -ENOMEM; 632 page = (char *)get_zeroed_page(GFP_KERNEL); 633 if (!page) 634 goto out; 635 636 length = -EFAULT; 637 if (copy_from_user(page, buf, count)) 638 goto out; 639 640 length = -EINVAL; 641 if (sscanf(page, "%u", &new_value) != 1) 642 goto out; 643 644 selinux_checkreqprot = new_value ? 1 : 0; 645 length = count; 646 out: 647 free_page((unsigned long) page); 648 return length; 649 } 650 static const struct file_operations sel_checkreqprot_ops = { 651 .read = sel_read_checkreqprot, 652 .write = sel_write_checkreqprot, 653 .llseek = generic_file_llseek, 654 }; 655 656 /* 657 * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c 658 */ 659 static ssize_t sel_write_access(struct file *file, char *buf, size_t size); 660 static ssize_t sel_write_create(struct file *file, char *buf, size_t size); 661 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size); 662 static ssize_t sel_write_user(struct file *file, char *buf, size_t size); 663 static ssize_t sel_write_member(struct file *file, char *buf, size_t size); 664 665 static ssize_t (*write_op[])(struct file *, char *, size_t) = { 666 [SEL_ACCESS] = sel_write_access, 667 [SEL_CREATE] = sel_write_create, 668 [SEL_RELABEL] = sel_write_relabel, 669 [SEL_USER] = sel_write_user, 670 [SEL_MEMBER] = sel_write_member, 671 [SEL_CONTEXT] = sel_write_context, 672 }; 673 674 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos) 675 { 676 ino_t ino = file_inode(file)->i_ino; 677 char *data; 678 ssize_t rv; 679 680 if (ino >= ARRAY_SIZE(write_op) || !write_op[ino]) 681 return -EINVAL; 682 683 data = simple_transaction_get(file, buf, size); 684 if (IS_ERR(data)) 685 return PTR_ERR(data); 686 687 rv = write_op[ino](file, data, size); 688 if (rv > 0) { 689 simple_transaction_set(file, rv); 690 rv = size; 691 } 692 return rv; 693 } 694 695 static const struct file_operations transaction_ops = { 696 .write = selinux_transaction_write, 697 .read = simple_transaction_read, 698 .release = simple_transaction_release, 699 .llseek = generic_file_llseek, 700 }; 701 702 /* 703 * payload - write methods 704 * If the method has a response, the response should be put in buf, 705 * and the length returned. Otherwise return 0 or and -error. 706 */ 707 708 static ssize_t sel_write_access(struct file *file, char *buf, size_t size) 709 { 710 char *scon = NULL, *tcon = NULL; 711 u32 ssid, tsid; 712 u16 tclass; 713 struct av_decision avd; 714 ssize_t length; 715 716 length = task_has_security(current, SECURITY__COMPUTE_AV); 717 if (length) 718 goto out; 719 720 length = -ENOMEM; 721 scon = kzalloc(size + 1, GFP_KERNEL); 722 if (!scon) 723 goto out; 724 725 length = -ENOMEM; 726 tcon = kzalloc(size + 1, GFP_KERNEL); 727 if (!tcon) 728 goto out; 729 730 length = -EINVAL; 731 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3) 732 goto out; 733 734 length = security_context_to_sid(scon, strlen(scon) + 1, &ssid, 735 GFP_KERNEL); 736 if (length) 737 goto out; 738 739 length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid, 740 GFP_KERNEL); 741 if (length) 742 goto out; 743 744 security_compute_av_user(ssid, tsid, tclass, &avd); 745 746 length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, 747 "%x %x %x %x %u %x", 748 avd.allowed, 0xffffffff, 749 avd.auditallow, avd.auditdeny, 750 avd.seqno, avd.flags); 751 out: 752 kfree(tcon); 753 kfree(scon); 754 return length; 755 } 756 757 static ssize_t sel_write_create(struct file *file, char *buf, size_t size) 758 { 759 char *scon = NULL, *tcon = NULL; 760 char *namebuf = NULL, *objname = NULL; 761 u32 ssid, tsid, newsid; 762 u16 tclass; 763 ssize_t length; 764 char *newcon = NULL; 765 u32 len; 766 int nargs; 767 768 length = task_has_security(current, SECURITY__COMPUTE_CREATE); 769 if (length) 770 goto out; 771 772 length = -ENOMEM; 773 scon = kzalloc(size + 1, GFP_KERNEL); 774 if (!scon) 775 goto out; 776 777 length = -ENOMEM; 778 tcon = kzalloc(size + 1, GFP_KERNEL); 779 if (!tcon) 780 goto out; 781 782 length = -ENOMEM; 783 namebuf = kzalloc(size + 1, GFP_KERNEL); 784 if (!namebuf) 785 goto out; 786 787 length = -EINVAL; 788 nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf); 789 if (nargs < 3 || nargs > 4) 790 goto out; 791 if (nargs == 4) { 792 /* 793 * If and when the name of new object to be queried contains 794 * either whitespace or multibyte characters, they shall be 795 * encoded based on the percentage-encoding rule. 796 * If not encoded, the sscanf logic picks up only left-half 797 * of the supplied name; splitted by a whitespace unexpectedly. 798 */ 799 char *r, *w; 800 int c1, c2; 801 802 r = w = namebuf; 803 do { 804 c1 = *r++; 805 if (c1 == '+') 806 c1 = ' '; 807 else if (c1 == '%') { 808 c1 = hex_to_bin(*r++); 809 if (c1 < 0) 810 goto out; 811 c2 = hex_to_bin(*r++); 812 if (c2 < 0) 813 goto out; 814 c1 = (c1 << 4) | c2; 815 } 816 *w++ = c1; 817 } while (c1 != '\0'); 818 819 objname = namebuf; 820 } 821 822 length = security_context_to_sid(scon, strlen(scon) + 1, &ssid, 823 GFP_KERNEL); 824 if (length) 825 goto out; 826 827 length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid, 828 GFP_KERNEL); 829 if (length) 830 goto out; 831 832 length = security_transition_sid_user(ssid, tsid, tclass, 833 objname, &newsid); 834 if (length) 835 goto out; 836 837 length = security_sid_to_context(newsid, &newcon, &len); 838 if (length) 839 goto out; 840 841 length = -ERANGE; 842 if (len > SIMPLE_TRANSACTION_LIMIT) { 843 printk(KERN_ERR "SELinux: %s: context size (%u) exceeds " 844 "payload max\n", __func__, len); 845 goto out; 846 } 847 848 memcpy(buf, newcon, len); 849 length = len; 850 out: 851 kfree(newcon); 852 kfree(namebuf); 853 kfree(tcon); 854 kfree(scon); 855 return length; 856 } 857 858 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size) 859 { 860 char *scon = NULL, *tcon = NULL; 861 u32 ssid, tsid, newsid; 862 u16 tclass; 863 ssize_t length; 864 char *newcon = NULL; 865 u32 len; 866 867 length = task_has_security(current, SECURITY__COMPUTE_RELABEL); 868 if (length) 869 goto out; 870 871 length = -ENOMEM; 872 scon = kzalloc(size + 1, GFP_KERNEL); 873 if (!scon) 874 goto out; 875 876 length = -ENOMEM; 877 tcon = kzalloc(size + 1, GFP_KERNEL); 878 if (!tcon) 879 goto out; 880 881 length = -EINVAL; 882 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3) 883 goto out; 884 885 length = security_context_to_sid(scon, strlen(scon) + 1, &ssid, 886 GFP_KERNEL); 887 if (length) 888 goto out; 889 890 length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid, 891 GFP_KERNEL); 892 if (length) 893 goto out; 894 895 length = security_change_sid(ssid, tsid, tclass, &newsid); 896 if (length) 897 goto out; 898 899 length = security_sid_to_context(newsid, &newcon, &len); 900 if (length) 901 goto out; 902 903 length = -ERANGE; 904 if (len > SIMPLE_TRANSACTION_LIMIT) 905 goto out; 906 907 memcpy(buf, newcon, len); 908 length = len; 909 out: 910 kfree(newcon); 911 kfree(tcon); 912 kfree(scon); 913 return length; 914 } 915 916 static ssize_t sel_write_user(struct file *file, char *buf, size_t size) 917 { 918 char *con = NULL, *user = NULL, *ptr; 919 u32 sid, *sids = NULL; 920 ssize_t length; 921 char *newcon; 922 int i, rc; 923 u32 len, nsids; 924 925 length = task_has_security(current, SECURITY__COMPUTE_USER); 926 if (length) 927 goto out; 928 929 length = -ENOMEM; 930 con = kzalloc(size + 1, GFP_KERNEL); 931 if (!con) 932 goto out; 933 934 length = -ENOMEM; 935 user = kzalloc(size + 1, GFP_KERNEL); 936 if (!user) 937 goto out; 938 939 length = -EINVAL; 940 if (sscanf(buf, "%s %s", con, user) != 2) 941 goto out; 942 943 length = security_context_to_sid(con, strlen(con) + 1, &sid, GFP_KERNEL); 944 if (length) 945 goto out; 946 947 length = security_get_user_sids(sid, user, &sids, &nsids); 948 if (length) 949 goto out; 950 951 length = sprintf(buf, "%u", nsids) + 1; 952 ptr = buf + length; 953 for (i = 0; i < nsids; i++) { 954 rc = security_sid_to_context(sids[i], &newcon, &len); 955 if (rc) { 956 length = rc; 957 goto out; 958 } 959 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) { 960 kfree(newcon); 961 length = -ERANGE; 962 goto out; 963 } 964 memcpy(ptr, newcon, len); 965 kfree(newcon); 966 ptr += len; 967 length += len; 968 } 969 out: 970 kfree(sids); 971 kfree(user); 972 kfree(con); 973 return length; 974 } 975 976 static ssize_t sel_write_member(struct file *file, char *buf, size_t size) 977 { 978 char *scon = NULL, *tcon = NULL; 979 u32 ssid, tsid, newsid; 980 u16 tclass; 981 ssize_t length; 982 char *newcon = NULL; 983 u32 len; 984 985 length = task_has_security(current, SECURITY__COMPUTE_MEMBER); 986 if (length) 987 goto out; 988 989 length = -ENOMEM; 990 scon = kzalloc(size + 1, GFP_KERNEL); 991 if (!scon) 992 goto out; 993 994 length = -ENOMEM; 995 tcon = kzalloc(size + 1, GFP_KERNEL); 996 if (!tcon) 997 goto out; 998 999 length = -EINVAL; 1000 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3) 1001 goto out; 1002 1003 length = security_context_to_sid(scon, strlen(scon) + 1, &ssid, 1004 GFP_KERNEL); 1005 if (length) 1006 goto out; 1007 1008 length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid, 1009 GFP_KERNEL); 1010 if (length) 1011 goto out; 1012 1013 length = security_member_sid(ssid, tsid, tclass, &newsid); 1014 if (length) 1015 goto out; 1016 1017 length = security_sid_to_context(newsid, &newcon, &len); 1018 if (length) 1019 goto out; 1020 1021 length = -ERANGE; 1022 if (len > SIMPLE_TRANSACTION_LIMIT) { 1023 printk(KERN_ERR "SELinux: %s: context size (%u) exceeds " 1024 "payload max\n", __func__, len); 1025 goto out; 1026 } 1027 1028 memcpy(buf, newcon, len); 1029 length = len; 1030 out: 1031 kfree(newcon); 1032 kfree(tcon); 1033 kfree(scon); 1034 return length; 1035 } 1036 1037 static struct inode *sel_make_inode(struct super_block *sb, int mode) 1038 { 1039 struct inode *ret = new_inode(sb); 1040 1041 if (ret) { 1042 ret->i_mode = mode; 1043 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME; 1044 } 1045 return ret; 1046 } 1047 1048 static ssize_t sel_read_bool(struct file *filep, char __user *buf, 1049 size_t count, loff_t *ppos) 1050 { 1051 char *page = NULL; 1052 ssize_t length; 1053 ssize_t ret; 1054 int cur_enforcing; 1055 unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK; 1056 const char *name = filep->f_path.dentry->d_name.name; 1057 1058 mutex_lock(&sel_mutex); 1059 1060 ret = -EINVAL; 1061 if (index >= bool_num || strcmp(name, bool_pending_names[index])) 1062 goto out; 1063 1064 ret = -ENOMEM; 1065 page = (char *)get_zeroed_page(GFP_KERNEL); 1066 if (!page) 1067 goto out; 1068 1069 cur_enforcing = security_get_bool_value(index); 1070 if (cur_enforcing < 0) { 1071 ret = cur_enforcing; 1072 goto out; 1073 } 1074 length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing, 1075 bool_pending_values[index]); 1076 ret = simple_read_from_buffer(buf, count, ppos, page, length); 1077 out: 1078 mutex_unlock(&sel_mutex); 1079 free_page((unsigned long)page); 1080 return ret; 1081 } 1082 1083 static ssize_t sel_write_bool(struct file *filep, const char __user *buf, 1084 size_t count, loff_t *ppos) 1085 { 1086 char *page = NULL; 1087 ssize_t length; 1088 int new_value; 1089 unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK; 1090 const char *name = filep->f_path.dentry->d_name.name; 1091 1092 mutex_lock(&sel_mutex); 1093 1094 length = task_has_security(current, SECURITY__SETBOOL); 1095 if (length) 1096 goto out; 1097 1098 length = -EINVAL; 1099 if (index >= bool_num || strcmp(name, bool_pending_names[index])) 1100 goto out; 1101 1102 length = -ENOMEM; 1103 if (count >= PAGE_SIZE) 1104 goto out; 1105 1106 /* No partial writes. */ 1107 length = -EINVAL; 1108 if (*ppos != 0) 1109 goto out; 1110 1111 length = -ENOMEM; 1112 page = (char *)get_zeroed_page(GFP_KERNEL); 1113 if (!page) 1114 goto out; 1115 1116 length = -EFAULT; 1117 if (copy_from_user(page, buf, count)) 1118 goto out; 1119 1120 length = -EINVAL; 1121 if (sscanf(page, "%d", &new_value) != 1) 1122 goto out; 1123 1124 if (new_value) 1125 new_value = 1; 1126 1127 bool_pending_values[index] = new_value; 1128 length = count; 1129 1130 out: 1131 mutex_unlock(&sel_mutex); 1132 free_page((unsigned long) page); 1133 return length; 1134 } 1135 1136 static const struct file_operations sel_bool_ops = { 1137 .read = sel_read_bool, 1138 .write = sel_write_bool, 1139 .llseek = generic_file_llseek, 1140 }; 1141 1142 static ssize_t sel_commit_bools_write(struct file *filep, 1143 const char __user *buf, 1144 size_t count, loff_t *ppos) 1145 { 1146 char *page = NULL; 1147 ssize_t length; 1148 int new_value; 1149 1150 mutex_lock(&sel_mutex); 1151 1152 length = task_has_security(current, SECURITY__SETBOOL); 1153 if (length) 1154 goto out; 1155 1156 length = -ENOMEM; 1157 if (count >= PAGE_SIZE) 1158 goto out; 1159 1160 /* No partial writes. */ 1161 length = -EINVAL; 1162 if (*ppos != 0) 1163 goto out; 1164 1165 length = -ENOMEM; 1166 page = (char *)get_zeroed_page(GFP_KERNEL); 1167 if (!page) 1168 goto out; 1169 1170 length = -EFAULT; 1171 if (copy_from_user(page, buf, count)) 1172 goto out; 1173 1174 length = -EINVAL; 1175 if (sscanf(page, "%d", &new_value) != 1) 1176 goto out; 1177 1178 length = 0; 1179 if (new_value && bool_pending_values) 1180 length = security_set_bools(bool_num, bool_pending_values); 1181 1182 if (!length) 1183 length = count; 1184 1185 out: 1186 mutex_unlock(&sel_mutex); 1187 free_page((unsigned long) page); 1188 return length; 1189 } 1190 1191 static const struct file_operations sel_commit_bools_ops = { 1192 .write = sel_commit_bools_write, 1193 .llseek = generic_file_llseek, 1194 }; 1195 1196 static void sel_remove_entries(struct dentry *de) 1197 { 1198 d_genocide(de); 1199 shrink_dcache_parent(de); 1200 } 1201 1202 #define BOOL_DIR_NAME "booleans" 1203 1204 static int sel_make_bools(void) 1205 { 1206 int i, ret; 1207 ssize_t len; 1208 struct dentry *dentry = NULL; 1209 struct dentry *dir = bool_dir; 1210 struct inode *inode = NULL; 1211 struct inode_security_struct *isec; 1212 char **names = NULL, *page; 1213 int num; 1214 int *values = NULL; 1215 u32 sid; 1216 1217 /* remove any existing files */ 1218 for (i = 0; i < bool_num; i++) 1219 kfree(bool_pending_names[i]); 1220 kfree(bool_pending_names); 1221 kfree(bool_pending_values); 1222 bool_num = 0; 1223 bool_pending_names = NULL; 1224 bool_pending_values = NULL; 1225 1226 sel_remove_entries(dir); 1227 1228 ret = -ENOMEM; 1229 page = (char *)get_zeroed_page(GFP_KERNEL); 1230 if (!page) 1231 goto out; 1232 1233 ret = security_get_bools(&num, &names, &values); 1234 if (ret) 1235 goto out; 1236 1237 for (i = 0; i < num; i++) { 1238 ret = -ENOMEM; 1239 dentry = d_alloc_name(dir, names[i]); 1240 if (!dentry) 1241 goto out; 1242 1243 ret = -ENOMEM; 1244 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR); 1245 if (!inode) 1246 goto out; 1247 1248 ret = -ENAMETOOLONG; 1249 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]); 1250 if (len >= PAGE_SIZE) 1251 goto out; 1252 1253 isec = (struct inode_security_struct *)inode->i_security; 1254 ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid); 1255 if (ret) 1256 goto out; 1257 1258 isec->sid = sid; 1259 isec->initialized = 1; 1260 inode->i_fop = &sel_bool_ops; 1261 inode->i_ino = i|SEL_BOOL_INO_OFFSET; 1262 d_add(dentry, inode); 1263 } 1264 bool_num = num; 1265 bool_pending_names = names; 1266 bool_pending_values = values; 1267 1268 free_page((unsigned long)page); 1269 return 0; 1270 out: 1271 free_page((unsigned long)page); 1272 1273 if (names) { 1274 for (i = 0; i < num; i++) 1275 kfree(names[i]); 1276 kfree(names); 1277 } 1278 kfree(values); 1279 sel_remove_entries(dir); 1280 1281 return ret; 1282 } 1283 1284 #define NULL_FILE_NAME "null" 1285 1286 struct path selinux_null; 1287 1288 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf, 1289 size_t count, loff_t *ppos) 1290 { 1291 char tmpbuf[TMPBUFLEN]; 1292 ssize_t length; 1293 1294 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold); 1295 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1296 } 1297 1298 static ssize_t sel_write_avc_cache_threshold(struct file *file, 1299 const char __user *buf, 1300 size_t count, loff_t *ppos) 1301 1302 { 1303 char *page = NULL; 1304 ssize_t ret; 1305 int new_value; 1306 1307 ret = task_has_security(current, SECURITY__SETSECPARAM); 1308 if (ret) 1309 goto out; 1310 1311 ret = -ENOMEM; 1312 if (count >= PAGE_SIZE) 1313 goto out; 1314 1315 /* No partial writes. */ 1316 ret = -EINVAL; 1317 if (*ppos != 0) 1318 goto out; 1319 1320 ret = -ENOMEM; 1321 page = (char *)get_zeroed_page(GFP_KERNEL); 1322 if (!page) 1323 goto out; 1324 1325 ret = -EFAULT; 1326 if (copy_from_user(page, buf, count)) 1327 goto out; 1328 1329 ret = -EINVAL; 1330 if (sscanf(page, "%u", &new_value) != 1) 1331 goto out; 1332 1333 avc_cache_threshold = new_value; 1334 1335 ret = count; 1336 out: 1337 free_page((unsigned long)page); 1338 return ret; 1339 } 1340 1341 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf, 1342 size_t count, loff_t *ppos) 1343 { 1344 char *page; 1345 ssize_t length; 1346 1347 page = (char *)__get_free_page(GFP_KERNEL); 1348 if (!page) 1349 return -ENOMEM; 1350 1351 length = avc_get_hash_stats(page); 1352 if (length >= 0) 1353 length = simple_read_from_buffer(buf, count, ppos, page, length); 1354 free_page((unsigned long)page); 1355 1356 return length; 1357 } 1358 1359 static const struct file_operations sel_avc_cache_threshold_ops = { 1360 .read = sel_read_avc_cache_threshold, 1361 .write = sel_write_avc_cache_threshold, 1362 .llseek = generic_file_llseek, 1363 }; 1364 1365 static const struct file_operations sel_avc_hash_stats_ops = { 1366 .read = sel_read_avc_hash_stats, 1367 .llseek = generic_file_llseek, 1368 }; 1369 1370 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS 1371 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx) 1372 { 1373 int cpu; 1374 1375 for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) { 1376 if (!cpu_possible(cpu)) 1377 continue; 1378 *idx = cpu + 1; 1379 return &per_cpu(avc_cache_stats, cpu); 1380 } 1381 return NULL; 1382 } 1383 1384 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos) 1385 { 1386 loff_t n = *pos - 1; 1387 1388 if (*pos == 0) 1389 return SEQ_START_TOKEN; 1390 1391 return sel_avc_get_stat_idx(&n); 1392 } 1393 1394 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos) 1395 { 1396 return sel_avc_get_stat_idx(pos); 1397 } 1398 1399 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v) 1400 { 1401 struct avc_cache_stats *st = v; 1402 1403 if (v == SEQ_START_TOKEN) 1404 seq_printf(seq, "lookups hits misses allocations reclaims " 1405 "frees\n"); 1406 else { 1407 unsigned int lookups = st->lookups; 1408 unsigned int misses = st->misses; 1409 unsigned int hits = lookups - misses; 1410 seq_printf(seq, "%u %u %u %u %u %u\n", lookups, 1411 hits, misses, st->allocations, 1412 st->reclaims, st->frees); 1413 } 1414 return 0; 1415 } 1416 1417 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v) 1418 { } 1419 1420 static const struct seq_operations sel_avc_cache_stats_seq_ops = { 1421 .start = sel_avc_stats_seq_start, 1422 .next = sel_avc_stats_seq_next, 1423 .show = sel_avc_stats_seq_show, 1424 .stop = sel_avc_stats_seq_stop, 1425 }; 1426 1427 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file) 1428 { 1429 return seq_open(file, &sel_avc_cache_stats_seq_ops); 1430 } 1431 1432 static const struct file_operations sel_avc_cache_stats_ops = { 1433 .open = sel_open_avc_cache_stats, 1434 .read = seq_read, 1435 .llseek = seq_lseek, 1436 .release = seq_release, 1437 }; 1438 #endif 1439 1440 static int sel_make_avc_files(struct dentry *dir) 1441 { 1442 int i; 1443 static struct tree_descr files[] = { 1444 { "cache_threshold", 1445 &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR }, 1446 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO }, 1447 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS 1448 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO }, 1449 #endif 1450 }; 1451 1452 for (i = 0; i < ARRAY_SIZE(files); i++) { 1453 struct inode *inode; 1454 struct dentry *dentry; 1455 1456 dentry = d_alloc_name(dir, files[i].name); 1457 if (!dentry) 1458 return -ENOMEM; 1459 1460 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode); 1461 if (!inode) 1462 return -ENOMEM; 1463 1464 inode->i_fop = files[i].ops; 1465 inode->i_ino = ++sel_last_ino; 1466 d_add(dentry, inode); 1467 } 1468 1469 return 0; 1470 } 1471 1472 static ssize_t sel_read_initcon(struct file *file, char __user *buf, 1473 size_t count, loff_t *ppos) 1474 { 1475 char *con; 1476 u32 sid, len; 1477 ssize_t ret; 1478 1479 sid = file_inode(file)->i_ino&SEL_INO_MASK; 1480 ret = security_sid_to_context(sid, &con, &len); 1481 if (ret) 1482 return ret; 1483 1484 ret = simple_read_from_buffer(buf, count, ppos, con, len); 1485 kfree(con); 1486 return ret; 1487 } 1488 1489 static const struct file_operations sel_initcon_ops = { 1490 .read = sel_read_initcon, 1491 .llseek = generic_file_llseek, 1492 }; 1493 1494 static int sel_make_initcon_files(struct dentry *dir) 1495 { 1496 int i; 1497 1498 for (i = 1; i <= SECINITSID_NUM; i++) { 1499 struct inode *inode; 1500 struct dentry *dentry; 1501 dentry = d_alloc_name(dir, security_get_initial_sid_context(i)); 1502 if (!dentry) 1503 return -ENOMEM; 1504 1505 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO); 1506 if (!inode) 1507 return -ENOMEM; 1508 1509 inode->i_fop = &sel_initcon_ops; 1510 inode->i_ino = i|SEL_INITCON_INO_OFFSET; 1511 d_add(dentry, inode); 1512 } 1513 1514 return 0; 1515 } 1516 1517 static inline unsigned long sel_class_to_ino(u16 class) 1518 { 1519 return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET; 1520 } 1521 1522 static inline u16 sel_ino_to_class(unsigned long ino) 1523 { 1524 return (ino & SEL_INO_MASK) / (SEL_VEC_MAX + 1); 1525 } 1526 1527 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm) 1528 { 1529 return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET; 1530 } 1531 1532 static inline u32 sel_ino_to_perm(unsigned long ino) 1533 { 1534 return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1); 1535 } 1536 1537 static ssize_t sel_read_class(struct file *file, char __user *buf, 1538 size_t count, loff_t *ppos) 1539 { 1540 unsigned long ino = file_inode(file)->i_ino; 1541 char res[TMPBUFLEN]; 1542 ssize_t len = snprintf(res, sizeof(res), "%d", sel_ino_to_class(ino)); 1543 return simple_read_from_buffer(buf, count, ppos, res, len); 1544 } 1545 1546 static const struct file_operations sel_class_ops = { 1547 .read = sel_read_class, 1548 .llseek = generic_file_llseek, 1549 }; 1550 1551 static ssize_t sel_read_perm(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_perm(ino)); 1557 return simple_read_from_buffer(buf, count, ppos, res, len); 1558 } 1559 1560 static const struct file_operations sel_perm_ops = { 1561 .read = sel_read_perm, 1562 .llseek = generic_file_llseek, 1563 }; 1564 1565 static ssize_t sel_read_policycap(struct file *file, char __user *buf, 1566 size_t count, loff_t *ppos) 1567 { 1568 int value; 1569 char tmpbuf[TMPBUFLEN]; 1570 ssize_t length; 1571 unsigned long i_ino = file_inode(file)->i_ino; 1572 1573 value = security_policycap_supported(i_ino & SEL_INO_MASK); 1574 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value); 1575 1576 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1577 } 1578 1579 static const struct file_operations sel_policycap_ops = { 1580 .read = sel_read_policycap, 1581 .llseek = generic_file_llseek, 1582 }; 1583 1584 static int sel_make_perm_files(char *objclass, int classvalue, 1585 struct dentry *dir) 1586 { 1587 int i, rc, nperms; 1588 char **perms; 1589 1590 rc = security_get_permissions(objclass, &perms, &nperms); 1591 if (rc) 1592 return rc; 1593 1594 for (i = 0; i < nperms; i++) { 1595 struct inode *inode; 1596 struct dentry *dentry; 1597 1598 rc = -ENOMEM; 1599 dentry = d_alloc_name(dir, perms[i]); 1600 if (!dentry) 1601 goto out; 1602 1603 rc = -ENOMEM; 1604 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO); 1605 if (!inode) 1606 goto out; 1607 1608 inode->i_fop = &sel_perm_ops; 1609 /* i+1 since perm values are 1-indexed */ 1610 inode->i_ino = sel_perm_to_ino(classvalue, i + 1); 1611 d_add(dentry, inode); 1612 } 1613 rc = 0; 1614 out: 1615 for (i = 0; i < nperms; i++) 1616 kfree(perms[i]); 1617 kfree(perms); 1618 return rc; 1619 } 1620 1621 static int sel_make_class_dir_entries(char *classname, int index, 1622 struct dentry *dir) 1623 { 1624 struct dentry *dentry = NULL; 1625 struct inode *inode = NULL; 1626 int rc; 1627 1628 dentry = d_alloc_name(dir, "index"); 1629 if (!dentry) 1630 return -ENOMEM; 1631 1632 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO); 1633 if (!inode) 1634 return -ENOMEM; 1635 1636 inode->i_fop = &sel_class_ops; 1637 inode->i_ino = sel_class_to_ino(index); 1638 d_add(dentry, inode); 1639 1640 dentry = sel_make_dir(dir, "perms", &last_class_ino); 1641 if (IS_ERR(dentry)) 1642 return PTR_ERR(dentry); 1643 1644 rc = sel_make_perm_files(classname, index, dentry); 1645 1646 return rc; 1647 } 1648 1649 static int sel_make_classes(void) 1650 { 1651 int rc, nclasses, i; 1652 char **classes; 1653 1654 /* delete any existing entries */ 1655 sel_remove_entries(class_dir); 1656 1657 rc = security_get_classes(&classes, &nclasses); 1658 if (rc) 1659 return rc; 1660 1661 /* +2 since classes are 1-indexed */ 1662 last_class_ino = sel_class_to_ino(nclasses + 2); 1663 1664 for (i = 0; i < nclasses; i++) { 1665 struct dentry *class_name_dir; 1666 1667 class_name_dir = sel_make_dir(class_dir, classes[i], 1668 &last_class_ino); 1669 if (IS_ERR(class_name_dir)) { 1670 rc = PTR_ERR(class_name_dir); 1671 goto out; 1672 } 1673 1674 /* i+1 since class values are 1-indexed */ 1675 rc = sel_make_class_dir_entries(classes[i], i + 1, 1676 class_name_dir); 1677 if (rc) 1678 goto out; 1679 } 1680 rc = 0; 1681 out: 1682 for (i = 0; i < nclasses; i++) 1683 kfree(classes[i]); 1684 kfree(classes); 1685 return rc; 1686 } 1687 1688 static int sel_make_policycap(void) 1689 { 1690 unsigned int iter; 1691 struct dentry *dentry = NULL; 1692 struct inode *inode = NULL; 1693 1694 sel_remove_entries(policycap_dir); 1695 1696 for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) { 1697 if (iter < ARRAY_SIZE(policycap_names)) 1698 dentry = d_alloc_name(policycap_dir, 1699 policycap_names[iter]); 1700 else 1701 dentry = d_alloc_name(policycap_dir, "unknown"); 1702 1703 if (dentry == NULL) 1704 return -ENOMEM; 1705 1706 inode = sel_make_inode(policycap_dir->d_sb, S_IFREG | S_IRUGO); 1707 if (inode == NULL) 1708 return -ENOMEM; 1709 1710 inode->i_fop = &sel_policycap_ops; 1711 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET; 1712 d_add(dentry, inode); 1713 } 1714 1715 return 0; 1716 } 1717 1718 static struct dentry *sel_make_dir(struct dentry *dir, const char *name, 1719 unsigned long *ino) 1720 { 1721 struct dentry *dentry = d_alloc_name(dir, name); 1722 struct inode *inode; 1723 1724 if (!dentry) 1725 return ERR_PTR(-ENOMEM); 1726 1727 inode = sel_make_inode(dir->d_sb, S_IFDIR | S_IRUGO | S_IXUGO); 1728 if (!inode) { 1729 dput(dentry); 1730 return ERR_PTR(-ENOMEM); 1731 } 1732 1733 inode->i_op = &simple_dir_inode_operations; 1734 inode->i_fop = &simple_dir_operations; 1735 inode->i_ino = ++(*ino); 1736 /* directory inodes start off with i_nlink == 2 (for "." entry) */ 1737 inc_nlink(inode); 1738 d_add(dentry, inode); 1739 /* bump link count on parent directory, too */ 1740 inc_nlink(dir->d_inode); 1741 1742 return dentry; 1743 } 1744 1745 static int sel_fill_super(struct super_block *sb, void *data, int silent) 1746 { 1747 int ret; 1748 struct dentry *dentry; 1749 struct inode *inode; 1750 struct inode_security_struct *isec; 1751 1752 static struct tree_descr selinux_files[] = { 1753 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR}, 1754 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR}, 1755 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO}, 1756 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO}, 1757 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO}, 1758 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO}, 1759 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO}, 1760 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO}, 1761 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR}, 1762 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO}, 1763 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR}, 1764 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO}, 1765 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR}, 1766 [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO}, 1767 [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO}, 1768 [SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO}, 1769 [SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUGO}, 1770 /* last one */ {""} 1771 }; 1772 ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files); 1773 if (ret) 1774 goto err; 1775 1776 bool_dir = sel_make_dir(sb->s_root, BOOL_DIR_NAME, &sel_last_ino); 1777 if (IS_ERR(bool_dir)) { 1778 ret = PTR_ERR(bool_dir); 1779 bool_dir = NULL; 1780 goto err; 1781 } 1782 1783 ret = -ENOMEM; 1784 dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME); 1785 if (!dentry) 1786 goto err; 1787 1788 ret = -ENOMEM; 1789 inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO); 1790 if (!inode) 1791 goto err; 1792 1793 inode->i_ino = ++sel_last_ino; 1794 isec = (struct inode_security_struct *)inode->i_security; 1795 isec->sid = SECINITSID_DEVNULL; 1796 isec->sclass = SECCLASS_CHR_FILE; 1797 isec->initialized = 1; 1798 1799 init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3)); 1800 d_add(dentry, inode); 1801 selinux_null.dentry = dentry; 1802 1803 dentry = sel_make_dir(sb->s_root, "avc", &sel_last_ino); 1804 if (IS_ERR(dentry)) { 1805 ret = PTR_ERR(dentry); 1806 goto err; 1807 } 1808 1809 ret = sel_make_avc_files(dentry); 1810 if (ret) 1811 goto err; 1812 1813 dentry = sel_make_dir(sb->s_root, "initial_contexts", &sel_last_ino); 1814 if (IS_ERR(dentry)) { 1815 ret = PTR_ERR(dentry); 1816 goto err; 1817 } 1818 1819 ret = sel_make_initcon_files(dentry); 1820 if (ret) 1821 goto err; 1822 1823 class_dir = sel_make_dir(sb->s_root, "class", &sel_last_ino); 1824 if (IS_ERR(class_dir)) { 1825 ret = PTR_ERR(class_dir); 1826 class_dir = NULL; 1827 goto err; 1828 } 1829 1830 policycap_dir = sel_make_dir(sb->s_root, "policy_capabilities", &sel_last_ino); 1831 if (IS_ERR(policycap_dir)) { 1832 ret = PTR_ERR(policycap_dir); 1833 policycap_dir = NULL; 1834 goto err; 1835 } 1836 return 0; 1837 err: 1838 printk(KERN_ERR "SELinux: %s: failed while creating inodes\n", 1839 __func__); 1840 return ret; 1841 } 1842 1843 static struct dentry *sel_mount(struct file_system_type *fs_type, 1844 int flags, const char *dev_name, void *data) 1845 { 1846 return mount_single(fs_type, flags, data, sel_fill_super); 1847 } 1848 1849 static struct file_system_type sel_fs_type = { 1850 .name = "selinuxfs", 1851 .mount = sel_mount, 1852 .kill_sb = kill_litter_super, 1853 }; 1854 1855 struct vfsmount *selinuxfs_mount; 1856 static struct kobject *selinuxfs_kobj; 1857 1858 static int __init init_sel_fs(void) 1859 { 1860 int err; 1861 1862 if (!selinux_enabled) 1863 return 0; 1864 1865 selinuxfs_kobj = kobject_create_and_add("selinux", fs_kobj); 1866 if (!selinuxfs_kobj) 1867 return -ENOMEM; 1868 1869 err = register_filesystem(&sel_fs_type); 1870 if (err) { 1871 kobject_put(selinuxfs_kobj); 1872 return err; 1873 } 1874 1875 selinux_null.mnt = selinuxfs_mount = kern_mount(&sel_fs_type); 1876 if (IS_ERR(selinuxfs_mount)) { 1877 printk(KERN_ERR "selinuxfs: could not mount!\n"); 1878 err = PTR_ERR(selinuxfs_mount); 1879 selinuxfs_mount = NULL; 1880 } 1881 1882 return err; 1883 } 1884 1885 __initcall(init_sel_fs); 1886 1887 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 1888 void exit_sel_fs(void) 1889 { 1890 kobject_put(selinuxfs_kobj); 1891 kern_unmount(selinuxfs_mount); 1892 unregister_filesystem(&sel_fs_type); 1893 } 1894 #endif 1895