1 /* Updated: Karl MacMillan <kmacmillan@tresys.com> 2 * 3 * Added conditional policy language extensions 4 * 5 * Copyright (C) 2003 - 2004 Tresys Technology, LLC 6 * Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com> 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License as published by 9 * the Free Software Foundation, version 2. 10 */ 11 12 #include <linux/config.h> 13 #include <linux/kernel.h> 14 #include <linux/pagemap.h> 15 #include <linux/slab.h> 16 #include <linux/vmalloc.h> 17 #include <linux/fs.h> 18 #include <linux/init.h> 19 #include <linux/string.h> 20 #include <linux/security.h> 21 #include <linux/major.h> 22 #include <linux/seq_file.h> 23 #include <linux/percpu.h> 24 #include <asm/uaccess.h> 25 #include <asm/semaphore.h> 26 27 /* selinuxfs pseudo filesystem for exporting the security policy API. 28 Based on the proc code and the fs/nfsd/nfsctl.c code. */ 29 30 #include "flask.h" 31 #include "avc.h" 32 #include "avc_ss.h" 33 #include "security.h" 34 #include "objsec.h" 35 #include "conditional.h" 36 37 unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE; 38 39 static int __init checkreqprot_setup(char *str) 40 { 41 selinux_checkreqprot = simple_strtoul(str,NULL,0) ? 1 : 0; 42 return 1; 43 } 44 __setup("checkreqprot=", checkreqprot_setup); 45 46 47 static DECLARE_MUTEX(sel_sem); 48 49 /* global data for booleans */ 50 static struct dentry *bool_dir = NULL; 51 static int bool_num = 0; 52 static int *bool_pending_values = NULL; 53 54 extern void selnl_notify_setenforce(int val); 55 56 /* Check whether a task is allowed to use a security operation. */ 57 static int task_has_security(struct task_struct *tsk, 58 u32 perms) 59 { 60 struct task_security_struct *tsec; 61 62 tsec = tsk->security; 63 if (!tsec) 64 return -EACCES; 65 66 return avc_has_perm(tsec->sid, SECINITSID_SECURITY, 67 SECCLASS_SECURITY, perms, NULL); 68 } 69 70 enum sel_inos { 71 SEL_ROOT_INO = 2, 72 SEL_LOAD, /* load policy */ 73 SEL_ENFORCE, /* get or set enforcing status */ 74 SEL_CONTEXT, /* validate context */ 75 SEL_ACCESS, /* compute access decision */ 76 SEL_CREATE, /* compute create labeling decision */ 77 SEL_RELABEL, /* compute relabeling decision */ 78 SEL_USER, /* compute reachable user contexts */ 79 SEL_POLICYVERS, /* return policy version for this kernel */ 80 SEL_COMMIT_BOOLS, /* commit new boolean values */ 81 SEL_MLS, /* return if MLS policy is enabled */ 82 SEL_DISABLE, /* disable SELinux until next reboot */ 83 SEL_AVC, /* AVC management directory */ 84 SEL_MEMBER, /* compute polyinstantiation membership decision */ 85 SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */ 86 }; 87 88 #define TMPBUFLEN 12 89 static ssize_t sel_read_enforce(struct file *filp, char __user *buf, 90 size_t count, loff_t *ppos) 91 { 92 char tmpbuf[TMPBUFLEN]; 93 ssize_t length; 94 95 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing); 96 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 97 } 98 99 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 100 static ssize_t sel_write_enforce(struct file * file, const char __user * buf, 101 size_t count, loff_t *ppos) 102 103 { 104 char *page; 105 ssize_t length; 106 int new_value; 107 108 if (count < 0 || count >= PAGE_SIZE) 109 return -ENOMEM; 110 if (*ppos != 0) { 111 /* No partial writes. */ 112 return -EINVAL; 113 } 114 page = (char*)get_zeroed_page(GFP_KERNEL); 115 if (!page) 116 return -ENOMEM; 117 length = -EFAULT; 118 if (copy_from_user(page, buf, count)) 119 goto out; 120 121 length = -EINVAL; 122 if (sscanf(page, "%d", &new_value) != 1) 123 goto out; 124 125 if (new_value != selinux_enforcing) { 126 length = task_has_security(current, SECURITY__SETENFORCE); 127 if (length) 128 goto out; 129 selinux_enforcing = new_value; 130 if (selinux_enforcing) 131 avc_ss_reset(0); 132 selnl_notify_setenforce(selinux_enforcing); 133 } 134 length = count; 135 out: 136 free_page((unsigned long) page); 137 return length; 138 } 139 #else 140 #define sel_write_enforce NULL 141 #endif 142 143 static struct file_operations sel_enforce_ops = { 144 .read = sel_read_enforce, 145 .write = sel_write_enforce, 146 }; 147 148 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 149 static ssize_t sel_write_disable(struct file * file, const char __user * buf, 150 size_t count, loff_t *ppos) 151 152 { 153 char *page; 154 ssize_t length; 155 int new_value; 156 extern int selinux_disable(void); 157 158 if (count < 0 || count >= PAGE_SIZE) 159 return -ENOMEM; 160 if (*ppos != 0) { 161 /* No partial writes. */ 162 return -EINVAL; 163 } 164 page = (char*)get_zeroed_page(GFP_KERNEL); 165 if (!page) 166 return -ENOMEM; 167 length = -EFAULT; 168 if (copy_from_user(page, buf, count)) 169 goto out; 170 171 length = -EINVAL; 172 if (sscanf(page, "%d", &new_value) != 1) 173 goto out; 174 175 if (new_value) { 176 length = selinux_disable(); 177 if (length < 0) 178 goto out; 179 } 180 181 length = count; 182 out: 183 free_page((unsigned long) page); 184 return length; 185 } 186 #else 187 #define sel_write_disable NULL 188 #endif 189 190 static struct file_operations sel_disable_ops = { 191 .write = sel_write_disable, 192 }; 193 194 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf, 195 size_t count, loff_t *ppos) 196 { 197 char tmpbuf[TMPBUFLEN]; 198 ssize_t length; 199 200 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX); 201 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 202 } 203 204 static struct file_operations sel_policyvers_ops = { 205 .read = sel_read_policyvers, 206 }; 207 208 /* declaration for sel_write_load */ 209 static int sel_make_bools(void); 210 211 static ssize_t sel_read_mls(struct file *filp, char __user *buf, 212 size_t count, loff_t *ppos) 213 { 214 char tmpbuf[TMPBUFLEN]; 215 ssize_t length; 216 217 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_mls_enabled); 218 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 219 } 220 221 static struct file_operations sel_mls_ops = { 222 .read = sel_read_mls, 223 }; 224 225 static ssize_t sel_write_load(struct file * file, const char __user * buf, 226 size_t count, loff_t *ppos) 227 228 { 229 int ret; 230 ssize_t length; 231 void *data = NULL; 232 233 down(&sel_sem); 234 235 length = task_has_security(current, SECURITY__LOAD_POLICY); 236 if (length) 237 goto out; 238 239 if (*ppos != 0) { 240 /* No partial writes. */ 241 length = -EINVAL; 242 goto out; 243 } 244 245 if ((count < 0) || (count > 64 * 1024 * 1024) 246 || (data = vmalloc(count)) == NULL) { 247 length = -ENOMEM; 248 goto out; 249 } 250 251 length = -EFAULT; 252 if (copy_from_user(data, buf, count) != 0) 253 goto out; 254 255 length = security_load_policy(data, count); 256 if (length) 257 goto out; 258 259 ret = sel_make_bools(); 260 if (ret) 261 length = ret; 262 else 263 length = count; 264 out: 265 up(&sel_sem); 266 vfree(data); 267 return length; 268 } 269 270 static struct file_operations sel_load_ops = { 271 .write = sel_write_load, 272 }; 273 274 275 static ssize_t sel_write_context(struct file * file, const char __user * buf, 276 size_t count, loff_t *ppos) 277 278 { 279 char *page; 280 u32 sid; 281 ssize_t length; 282 283 length = task_has_security(current, SECURITY__CHECK_CONTEXT); 284 if (length) 285 return length; 286 287 if (count < 0 || count >= PAGE_SIZE) 288 return -ENOMEM; 289 if (*ppos != 0) { 290 /* No partial writes. */ 291 return -EINVAL; 292 } 293 page = (char*)get_zeroed_page(GFP_KERNEL); 294 if (!page) 295 return -ENOMEM; 296 length = -EFAULT; 297 if (copy_from_user(page, buf, count)) 298 goto out; 299 300 length = security_context_to_sid(page, count, &sid); 301 if (length < 0) 302 goto out; 303 304 length = count; 305 out: 306 free_page((unsigned long) page); 307 return length; 308 } 309 310 static struct file_operations sel_context_ops = { 311 .write = sel_write_context, 312 }; 313 314 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf, 315 size_t count, loff_t *ppos) 316 { 317 char tmpbuf[TMPBUFLEN]; 318 ssize_t length; 319 320 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot); 321 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 322 } 323 324 static ssize_t sel_write_checkreqprot(struct file * file, const char __user * buf, 325 size_t count, loff_t *ppos) 326 { 327 char *page; 328 ssize_t length; 329 unsigned int new_value; 330 331 length = task_has_security(current, SECURITY__SETCHECKREQPROT); 332 if (length) 333 return length; 334 335 if (count < 0 || count >= PAGE_SIZE) 336 return -ENOMEM; 337 if (*ppos != 0) { 338 /* No partial writes. */ 339 return -EINVAL; 340 } 341 page = (char*)get_zeroed_page(GFP_KERNEL); 342 if (!page) 343 return -ENOMEM; 344 length = -EFAULT; 345 if (copy_from_user(page, buf, count)) 346 goto out; 347 348 length = -EINVAL; 349 if (sscanf(page, "%u", &new_value) != 1) 350 goto out; 351 352 selinux_checkreqprot = new_value ? 1 : 0; 353 length = count; 354 out: 355 free_page((unsigned long) page); 356 return length; 357 } 358 static struct file_operations sel_checkreqprot_ops = { 359 .read = sel_read_checkreqprot, 360 .write = sel_write_checkreqprot, 361 }; 362 363 /* 364 * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c 365 */ 366 static ssize_t sel_write_access(struct file * file, char *buf, size_t size); 367 static ssize_t sel_write_create(struct file * file, char *buf, size_t size); 368 static ssize_t sel_write_relabel(struct file * file, char *buf, size_t size); 369 static ssize_t sel_write_user(struct file * file, char *buf, size_t size); 370 static ssize_t sel_write_member(struct file * file, char *buf, size_t size); 371 372 static ssize_t (*write_op[])(struct file *, char *, size_t) = { 373 [SEL_ACCESS] = sel_write_access, 374 [SEL_CREATE] = sel_write_create, 375 [SEL_RELABEL] = sel_write_relabel, 376 [SEL_USER] = sel_write_user, 377 [SEL_MEMBER] = sel_write_member, 378 }; 379 380 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos) 381 { 382 ino_t ino = file->f_dentry->d_inode->i_ino; 383 char *data; 384 ssize_t rv; 385 386 if (ino >= sizeof(write_op)/sizeof(write_op[0]) || !write_op[ino]) 387 return -EINVAL; 388 389 data = simple_transaction_get(file, buf, size); 390 if (IS_ERR(data)) 391 return PTR_ERR(data); 392 393 rv = write_op[ino](file, data, size); 394 if (rv>0) { 395 simple_transaction_set(file, rv); 396 rv = size; 397 } 398 return rv; 399 } 400 401 static struct file_operations transaction_ops = { 402 .write = selinux_transaction_write, 403 .read = simple_transaction_read, 404 .release = simple_transaction_release, 405 }; 406 407 /* 408 * payload - write methods 409 * If the method has a response, the response should be put in buf, 410 * and the length returned. Otherwise return 0 or and -error. 411 */ 412 413 static ssize_t sel_write_access(struct file * file, char *buf, size_t size) 414 { 415 char *scon, *tcon; 416 u32 ssid, tsid; 417 u16 tclass; 418 u32 req; 419 struct av_decision avd; 420 ssize_t length; 421 422 length = task_has_security(current, SECURITY__COMPUTE_AV); 423 if (length) 424 return length; 425 426 length = -ENOMEM; 427 scon = kmalloc(size+1, GFP_KERNEL); 428 if (!scon) 429 return length; 430 memset(scon, 0, size+1); 431 432 tcon = kmalloc(size+1, GFP_KERNEL); 433 if (!tcon) 434 goto out; 435 memset(tcon, 0, size+1); 436 437 length = -EINVAL; 438 if (sscanf(buf, "%s %s %hu %x", scon, tcon, &tclass, &req) != 4) 439 goto out2; 440 441 length = security_context_to_sid(scon, strlen(scon)+1, &ssid); 442 if (length < 0) 443 goto out2; 444 length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid); 445 if (length < 0) 446 goto out2; 447 448 length = security_compute_av(ssid, tsid, tclass, req, &avd); 449 if (length < 0) 450 goto out2; 451 452 length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, 453 "%x %x %x %x %u", 454 avd.allowed, avd.decided, 455 avd.auditallow, avd.auditdeny, 456 avd.seqno); 457 out2: 458 kfree(tcon); 459 out: 460 kfree(scon); 461 return length; 462 } 463 464 static ssize_t sel_write_create(struct file * file, char *buf, size_t size) 465 { 466 char *scon, *tcon; 467 u32 ssid, tsid, newsid; 468 u16 tclass; 469 ssize_t length; 470 char *newcon; 471 u32 len; 472 473 length = task_has_security(current, SECURITY__COMPUTE_CREATE); 474 if (length) 475 return length; 476 477 length = -ENOMEM; 478 scon = kmalloc(size+1, GFP_KERNEL); 479 if (!scon) 480 return length; 481 memset(scon, 0, size+1); 482 483 tcon = kmalloc(size+1, GFP_KERNEL); 484 if (!tcon) 485 goto out; 486 memset(tcon, 0, size+1); 487 488 length = -EINVAL; 489 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3) 490 goto out2; 491 492 length = security_context_to_sid(scon, strlen(scon)+1, &ssid); 493 if (length < 0) 494 goto out2; 495 length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid); 496 if (length < 0) 497 goto out2; 498 499 length = security_transition_sid(ssid, tsid, tclass, &newsid); 500 if (length < 0) 501 goto out2; 502 503 length = security_sid_to_context(newsid, &newcon, &len); 504 if (length < 0) 505 goto out2; 506 507 if (len > SIMPLE_TRANSACTION_LIMIT) { 508 printk(KERN_ERR "%s: context size (%u) exceeds payload " 509 "max\n", __FUNCTION__, len); 510 length = -ERANGE; 511 goto out3; 512 } 513 514 memcpy(buf, newcon, len); 515 length = len; 516 out3: 517 kfree(newcon); 518 out2: 519 kfree(tcon); 520 out: 521 kfree(scon); 522 return length; 523 } 524 525 static ssize_t sel_write_relabel(struct file * file, char *buf, size_t size) 526 { 527 char *scon, *tcon; 528 u32 ssid, tsid, newsid; 529 u16 tclass; 530 ssize_t length; 531 char *newcon; 532 u32 len; 533 534 length = task_has_security(current, SECURITY__COMPUTE_RELABEL); 535 if (length) 536 return length; 537 538 length = -ENOMEM; 539 scon = kmalloc(size+1, GFP_KERNEL); 540 if (!scon) 541 return length; 542 memset(scon, 0, size+1); 543 544 tcon = kmalloc(size+1, GFP_KERNEL); 545 if (!tcon) 546 goto out; 547 memset(tcon, 0, size+1); 548 549 length = -EINVAL; 550 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3) 551 goto out2; 552 553 length = security_context_to_sid(scon, strlen(scon)+1, &ssid); 554 if (length < 0) 555 goto out2; 556 length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid); 557 if (length < 0) 558 goto out2; 559 560 length = security_change_sid(ssid, tsid, tclass, &newsid); 561 if (length < 0) 562 goto out2; 563 564 length = security_sid_to_context(newsid, &newcon, &len); 565 if (length < 0) 566 goto out2; 567 568 if (len > SIMPLE_TRANSACTION_LIMIT) { 569 length = -ERANGE; 570 goto out3; 571 } 572 573 memcpy(buf, newcon, len); 574 length = len; 575 out3: 576 kfree(newcon); 577 out2: 578 kfree(tcon); 579 out: 580 kfree(scon); 581 return length; 582 } 583 584 static ssize_t sel_write_user(struct file * file, char *buf, size_t size) 585 { 586 char *con, *user, *ptr; 587 u32 sid, *sids; 588 ssize_t length; 589 char *newcon; 590 int i, rc; 591 u32 len, nsids; 592 593 length = task_has_security(current, SECURITY__COMPUTE_USER); 594 if (length) 595 return length; 596 597 length = -ENOMEM; 598 con = kmalloc(size+1, GFP_KERNEL); 599 if (!con) 600 return length; 601 memset(con, 0, size+1); 602 603 user = kmalloc(size+1, GFP_KERNEL); 604 if (!user) 605 goto out; 606 memset(user, 0, size+1); 607 608 length = -EINVAL; 609 if (sscanf(buf, "%s %s", con, user) != 2) 610 goto out2; 611 612 length = security_context_to_sid(con, strlen(con)+1, &sid); 613 if (length < 0) 614 goto out2; 615 616 length = security_get_user_sids(sid, user, &sids, &nsids); 617 if (length < 0) 618 goto out2; 619 620 length = sprintf(buf, "%u", nsids) + 1; 621 ptr = buf + length; 622 for (i = 0; i < nsids; i++) { 623 rc = security_sid_to_context(sids[i], &newcon, &len); 624 if (rc) { 625 length = rc; 626 goto out3; 627 } 628 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) { 629 kfree(newcon); 630 length = -ERANGE; 631 goto out3; 632 } 633 memcpy(ptr, newcon, len); 634 kfree(newcon); 635 ptr += len; 636 length += len; 637 } 638 out3: 639 kfree(sids); 640 out2: 641 kfree(user); 642 out: 643 kfree(con); 644 return length; 645 } 646 647 static ssize_t sel_write_member(struct file * file, char *buf, size_t size) 648 { 649 char *scon, *tcon; 650 u32 ssid, tsid, newsid; 651 u16 tclass; 652 ssize_t length; 653 char *newcon; 654 u32 len; 655 656 length = task_has_security(current, SECURITY__COMPUTE_MEMBER); 657 if (length) 658 return length; 659 660 length = -ENOMEM; 661 scon = kmalloc(size+1, GFP_KERNEL); 662 if (!scon) 663 return length; 664 memset(scon, 0, size+1); 665 666 tcon = kmalloc(size+1, GFP_KERNEL); 667 if (!tcon) 668 goto out; 669 memset(tcon, 0, size+1); 670 671 length = -EINVAL; 672 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3) 673 goto out2; 674 675 length = security_context_to_sid(scon, strlen(scon)+1, &ssid); 676 if (length < 0) 677 goto out2; 678 length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid); 679 if (length < 0) 680 goto out2; 681 682 length = security_member_sid(ssid, tsid, tclass, &newsid); 683 if (length < 0) 684 goto out2; 685 686 length = security_sid_to_context(newsid, &newcon, &len); 687 if (length < 0) 688 goto out2; 689 690 if (len > SIMPLE_TRANSACTION_LIMIT) { 691 printk(KERN_ERR "%s: context size (%u) exceeds payload " 692 "max\n", __FUNCTION__, len); 693 length = -ERANGE; 694 goto out3; 695 } 696 697 memcpy(buf, newcon, len); 698 length = len; 699 out3: 700 kfree(newcon); 701 out2: 702 kfree(tcon); 703 out: 704 kfree(scon); 705 return length; 706 } 707 708 static struct inode *sel_make_inode(struct super_block *sb, int mode) 709 { 710 struct inode *ret = new_inode(sb); 711 712 if (ret) { 713 ret->i_mode = mode; 714 ret->i_uid = ret->i_gid = 0; 715 ret->i_blksize = PAGE_CACHE_SIZE; 716 ret->i_blocks = 0; 717 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME; 718 } 719 return ret; 720 } 721 722 #define BOOL_INO_OFFSET 30 723 724 static ssize_t sel_read_bool(struct file *filep, char __user *buf, 725 size_t count, loff_t *ppos) 726 { 727 char *page = NULL; 728 ssize_t length; 729 ssize_t end; 730 ssize_t ret; 731 int cur_enforcing; 732 struct inode *inode; 733 734 down(&sel_sem); 735 736 ret = -EFAULT; 737 738 /* check to see if this file has been deleted */ 739 if (!filep->f_op) 740 goto out; 741 742 if (count < 0 || count > PAGE_SIZE) { 743 ret = -EINVAL; 744 goto out; 745 } 746 if (!(page = (char*)get_zeroed_page(GFP_KERNEL))) { 747 ret = -ENOMEM; 748 goto out; 749 } 750 751 inode = filep->f_dentry->d_inode; 752 cur_enforcing = security_get_bool_value(inode->i_ino - BOOL_INO_OFFSET); 753 if (cur_enforcing < 0) { 754 ret = cur_enforcing; 755 goto out; 756 } 757 758 length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing, 759 bool_pending_values[inode->i_ino - BOOL_INO_OFFSET]); 760 if (length < 0) { 761 ret = length; 762 goto out; 763 } 764 765 if (*ppos >= length) { 766 ret = 0; 767 goto out; 768 } 769 if (count + *ppos > length) 770 count = length - *ppos; 771 end = count + *ppos; 772 if (copy_to_user(buf, (char *) page + *ppos, count)) { 773 ret = -EFAULT; 774 goto out; 775 } 776 *ppos = end; 777 ret = count; 778 out: 779 up(&sel_sem); 780 if (page) 781 free_page((unsigned long)page); 782 return ret; 783 } 784 785 static ssize_t sel_write_bool(struct file *filep, const char __user *buf, 786 size_t count, loff_t *ppos) 787 { 788 char *page = NULL; 789 ssize_t length = -EFAULT; 790 int new_value; 791 struct inode *inode; 792 793 down(&sel_sem); 794 795 length = task_has_security(current, SECURITY__SETBOOL); 796 if (length) 797 goto out; 798 799 /* check to see if this file has been deleted */ 800 if (!filep->f_op) 801 goto out; 802 803 if (count < 0 || count >= PAGE_SIZE) { 804 length = -ENOMEM; 805 goto out; 806 } 807 if (*ppos != 0) { 808 /* No partial writes. */ 809 goto out; 810 } 811 page = (char*)get_zeroed_page(GFP_KERNEL); 812 if (!page) { 813 length = -ENOMEM; 814 goto out; 815 } 816 817 if (copy_from_user(page, buf, count)) 818 goto out; 819 820 length = -EINVAL; 821 if (sscanf(page, "%d", &new_value) != 1) 822 goto out; 823 824 if (new_value) 825 new_value = 1; 826 827 inode = filep->f_dentry->d_inode; 828 bool_pending_values[inode->i_ino - BOOL_INO_OFFSET] = new_value; 829 length = count; 830 831 out: 832 up(&sel_sem); 833 if (page) 834 free_page((unsigned long) page); 835 return length; 836 } 837 838 static struct file_operations sel_bool_ops = { 839 .read = sel_read_bool, 840 .write = sel_write_bool, 841 }; 842 843 static ssize_t sel_commit_bools_write(struct file *filep, 844 const char __user *buf, 845 size_t count, loff_t *ppos) 846 { 847 char *page = NULL; 848 ssize_t length = -EFAULT; 849 int new_value; 850 851 down(&sel_sem); 852 853 length = task_has_security(current, SECURITY__SETBOOL); 854 if (length) 855 goto out; 856 857 /* check to see if this file has been deleted */ 858 if (!filep->f_op) 859 goto out; 860 861 if (count < 0 || count >= PAGE_SIZE) { 862 length = -ENOMEM; 863 goto out; 864 } 865 if (*ppos != 0) { 866 /* No partial writes. */ 867 goto out; 868 } 869 page = (char*)get_zeroed_page(GFP_KERNEL); 870 if (!page) { 871 length = -ENOMEM; 872 goto out; 873 } 874 875 if (copy_from_user(page, buf, count)) 876 goto out; 877 878 length = -EINVAL; 879 if (sscanf(page, "%d", &new_value) != 1) 880 goto out; 881 882 if (new_value) { 883 security_set_bools(bool_num, bool_pending_values); 884 } 885 886 length = count; 887 888 out: 889 up(&sel_sem); 890 if (page) 891 free_page((unsigned long) page); 892 return length; 893 } 894 895 static struct file_operations sel_commit_bools_ops = { 896 .write = sel_commit_bools_write, 897 }; 898 899 /* delete booleans - partial revoke() from 900 * fs/proc/generic.c proc_kill_inodes */ 901 static void sel_remove_bools(struct dentry *de) 902 { 903 struct list_head *p, *node; 904 struct super_block *sb = de->d_sb; 905 906 spin_lock(&dcache_lock); 907 node = de->d_subdirs.next; 908 while (node != &de->d_subdirs) { 909 struct dentry *d = list_entry(node, struct dentry, d_child); 910 list_del_init(node); 911 912 if (d->d_inode) { 913 d = dget_locked(d); 914 spin_unlock(&dcache_lock); 915 d_delete(d); 916 simple_unlink(de->d_inode, d); 917 dput(d); 918 spin_lock(&dcache_lock); 919 } 920 node = de->d_subdirs.next; 921 } 922 923 spin_unlock(&dcache_lock); 924 925 file_list_lock(); 926 list_for_each(p, &sb->s_files) { 927 struct file * filp = list_entry(p, struct file, f_list); 928 struct dentry * dentry = filp->f_dentry; 929 930 if (dentry->d_parent != de) { 931 continue; 932 } 933 filp->f_op = NULL; 934 } 935 file_list_unlock(); 936 } 937 938 #define BOOL_DIR_NAME "booleans" 939 940 static int sel_make_bools(void) 941 { 942 int i, ret = 0; 943 ssize_t len; 944 struct dentry *dentry = NULL; 945 struct dentry *dir = bool_dir; 946 struct inode *inode = NULL; 947 struct inode_security_struct *isec; 948 char **names = NULL, *page; 949 int num; 950 int *values = NULL; 951 u32 sid; 952 953 /* remove any existing files */ 954 if (bool_pending_values) 955 kfree(bool_pending_values); 956 957 sel_remove_bools(dir); 958 959 if (!(page = (char*)get_zeroed_page(GFP_KERNEL))) 960 return -ENOMEM; 961 962 ret = security_get_bools(&num, &names, &values); 963 if (ret != 0) 964 goto out; 965 966 for (i = 0; i < num; i++) { 967 dentry = d_alloc_name(dir, names[i]); 968 if (!dentry) { 969 ret = -ENOMEM; 970 goto err; 971 } 972 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR); 973 if (!inode) { 974 ret = -ENOMEM; 975 goto err; 976 } 977 978 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]); 979 if (len < 0) { 980 ret = -EINVAL; 981 goto err; 982 } else if (len >= PAGE_SIZE) { 983 ret = -ENAMETOOLONG; 984 goto err; 985 } 986 isec = (struct inode_security_struct*)inode->i_security; 987 if ((ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid))) 988 goto err; 989 isec->sid = sid; 990 isec->initialized = 1; 991 inode->i_fop = &sel_bool_ops; 992 inode->i_ino = i + BOOL_INO_OFFSET; 993 d_add(dentry, inode); 994 } 995 bool_num = num; 996 bool_pending_values = values; 997 out: 998 free_page((unsigned long)page); 999 if (names) { 1000 for (i = 0; i < num; i++) { 1001 if (names[i]) 1002 kfree(names[i]); 1003 } 1004 kfree(names); 1005 } 1006 return ret; 1007 err: 1008 d_genocide(dir); 1009 ret = -ENOMEM; 1010 goto out; 1011 } 1012 1013 #define NULL_FILE_NAME "null" 1014 1015 struct dentry *selinux_null = NULL; 1016 1017 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf, 1018 size_t count, loff_t *ppos) 1019 { 1020 char tmpbuf[TMPBUFLEN]; 1021 ssize_t length; 1022 1023 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold); 1024 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1025 } 1026 1027 static ssize_t sel_write_avc_cache_threshold(struct file * file, 1028 const char __user * buf, 1029 size_t count, loff_t *ppos) 1030 1031 { 1032 char *page; 1033 ssize_t ret; 1034 int new_value; 1035 1036 if (count < 0 || count >= PAGE_SIZE) { 1037 ret = -ENOMEM; 1038 goto out; 1039 } 1040 1041 if (*ppos != 0) { 1042 /* No partial writes. */ 1043 ret = -EINVAL; 1044 goto out; 1045 } 1046 1047 page = (char*)get_zeroed_page(GFP_KERNEL); 1048 if (!page) { 1049 ret = -ENOMEM; 1050 goto out; 1051 } 1052 1053 if (copy_from_user(page, buf, count)) { 1054 ret = -EFAULT; 1055 goto out_free; 1056 } 1057 1058 if (sscanf(page, "%u", &new_value) != 1) { 1059 ret = -EINVAL; 1060 goto out; 1061 } 1062 1063 if (new_value != avc_cache_threshold) { 1064 ret = task_has_security(current, SECURITY__SETSECPARAM); 1065 if (ret) 1066 goto out_free; 1067 avc_cache_threshold = new_value; 1068 } 1069 ret = count; 1070 out_free: 1071 free_page((unsigned long)page); 1072 out: 1073 return ret; 1074 } 1075 1076 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf, 1077 size_t count, loff_t *ppos) 1078 { 1079 char *page; 1080 ssize_t ret = 0; 1081 1082 page = (char *)__get_free_page(GFP_KERNEL); 1083 if (!page) { 1084 ret = -ENOMEM; 1085 goto out; 1086 } 1087 ret = avc_get_hash_stats(page); 1088 if (ret >= 0) 1089 ret = simple_read_from_buffer(buf, count, ppos, page, ret); 1090 free_page((unsigned long)page); 1091 out: 1092 return ret; 1093 } 1094 1095 static struct file_operations sel_avc_cache_threshold_ops = { 1096 .read = sel_read_avc_cache_threshold, 1097 .write = sel_write_avc_cache_threshold, 1098 }; 1099 1100 static struct file_operations sel_avc_hash_stats_ops = { 1101 .read = sel_read_avc_hash_stats, 1102 }; 1103 1104 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS 1105 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx) 1106 { 1107 int cpu; 1108 1109 for (cpu = *idx; cpu < NR_CPUS; ++cpu) { 1110 if (!cpu_possible(cpu)) 1111 continue; 1112 *idx = cpu + 1; 1113 return &per_cpu(avc_cache_stats, cpu); 1114 } 1115 return NULL; 1116 } 1117 1118 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos) 1119 { 1120 loff_t n = *pos - 1; 1121 1122 if (*pos == 0) 1123 return SEQ_START_TOKEN; 1124 1125 return sel_avc_get_stat_idx(&n); 1126 } 1127 1128 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos) 1129 { 1130 return sel_avc_get_stat_idx(pos); 1131 } 1132 1133 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v) 1134 { 1135 struct avc_cache_stats *st = v; 1136 1137 if (v == SEQ_START_TOKEN) 1138 seq_printf(seq, "lookups hits misses allocations reclaims " 1139 "frees\n"); 1140 else 1141 seq_printf(seq, "%u %u %u %u %u %u\n", st->lookups, 1142 st->hits, st->misses, st->allocations, 1143 st->reclaims, st->frees); 1144 return 0; 1145 } 1146 1147 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v) 1148 { } 1149 1150 static struct seq_operations sel_avc_cache_stats_seq_ops = { 1151 .start = sel_avc_stats_seq_start, 1152 .next = sel_avc_stats_seq_next, 1153 .show = sel_avc_stats_seq_show, 1154 .stop = sel_avc_stats_seq_stop, 1155 }; 1156 1157 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file) 1158 { 1159 return seq_open(file, &sel_avc_cache_stats_seq_ops); 1160 } 1161 1162 static struct file_operations sel_avc_cache_stats_ops = { 1163 .open = sel_open_avc_cache_stats, 1164 .read = seq_read, 1165 .llseek = seq_lseek, 1166 .release = seq_release, 1167 }; 1168 #endif 1169 1170 static int sel_make_avc_files(struct dentry *dir) 1171 { 1172 int i, ret = 0; 1173 static struct tree_descr files[] = { 1174 { "cache_threshold", 1175 &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR }, 1176 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO }, 1177 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS 1178 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO }, 1179 #endif 1180 }; 1181 1182 for (i = 0; i < sizeof (files) / sizeof (files[0]); i++) { 1183 struct inode *inode; 1184 struct dentry *dentry; 1185 1186 dentry = d_alloc_name(dir, files[i].name); 1187 if (!dentry) { 1188 ret = -ENOMEM; 1189 goto err; 1190 } 1191 1192 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode); 1193 if (!inode) { 1194 ret = -ENOMEM; 1195 goto err; 1196 } 1197 inode->i_fop = files[i].ops; 1198 d_add(dentry, inode); 1199 } 1200 out: 1201 return ret; 1202 err: 1203 d_genocide(dir); 1204 goto out; 1205 } 1206 1207 static int sel_make_dir(struct super_block *sb, struct dentry *dentry) 1208 { 1209 int ret = 0; 1210 struct inode *inode; 1211 1212 inode = sel_make_inode(sb, S_IFDIR | S_IRUGO | S_IXUGO); 1213 if (!inode) { 1214 ret = -ENOMEM; 1215 goto out; 1216 } 1217 inode->i_op = &simple_dir_inode_operations; 1218 inode->i_fop = &simple_dir_operations; 1219 d_add(dentry, inode); 1220 out: 1221 return ret; 1222 } 1223 1224 static int sel_fill_super(struct super_block * sb, void * data, int silent) 1225 { 1226 int ret; 1227 struct dentry *dentry; 1228 struct inode *inode; 1229 struct inode_security_struct *isec; 1230 1231 static struct tree_descr selinux_files[] = { 1232 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR}, 1233 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR}, 1234 [SEL_CONTEXT] = {"context", &sel_context_ops, S_IRUGO|S_IWUGO}, 1235 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO}, 1236 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO}, 1237 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO}, 1238 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO}, 1239 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO}, 1240 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR}, 1241 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO}, 1242 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR}, 1243 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO}, 1244 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR}, 1245 /* last one */ {""} 1246 }; 1247 ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files); 1248 if (ret) 1249 return ret; 1250 1251 dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME); 1252 if (!dentry) 1253 return -ENOMEM; 1254 1255 inode = sel_make_inode(sb, S_IFDIR | S_IRUGO | S_IXUGO); 1256 if (!inode) 1257 goto out; 1258 inode->i_op = &simple_dir_inode_operations; 1259 inode->i_fop = &simple_dir_operations; 1260 d_add(dentry, inode); 1261 bool_dir = dentry; 1262 ret = sel_make_bools(); 1263 if (ret) 1264 goto out; 1265 1266 dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME); 1267 if (!dentry) 1268 return -ENOMEM; 1269 1270 inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO); 1271 if (!inode) 1272 goto out; 1273 isec = (struct inode_security_struct*)inode->i_security; 1274 isec->sid = SECINITSID_DEVNULL; 1275 isec->sclass = SECCLASS_CHR_FILE; 1276 isec->initialized = 1; 1277 1278 init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3)); 1279 d_add(dentry, inode); 1280 selinux_null = dentry; 1281 1282 dentry = d_alloc_name(sb->s_root, "avc"); 1283 if (!dentry) 1284 return -ENOMEM; 1285 1286 ret = sel_make_dir(sb, dentry); 1287 if (ret) 1288 goto out; 1289 1290 ret = sel_make_avc_files(dentry); 1291 if (ret) 1292 goto out; 1293 1294 return 0; 1295 out: 1296 dput(dentry); 1297 printk(KERN_ERR "%s: failed while creating inodes\n", __FUNCTION__); 1298 return -ENOMEM; 1299 } 1300 1301 static struct super_block *sel_get_sb(struct file_system_type *fs_type, 1302 int flags, const char *dev_name, void *data) 1303 { 1304 return get_sb_single(fs_type, flags, data, sel_fill_super); 1305 } 1306 1307 static struct file_system_type sel_fs_type = { 1308 .name = "selinuxfs", 1309 .get_sb = sel_get_sb, 1310 .kill_sb = kill_litter_super, 1311 }; 1312 1313 struct vfsmount *selinuxfs_mount; 1314 1315 static int __init init_sel_fs(void) 1316 { 1317 int err; 1318 1319 if (!selinux_enabled) 1320 return 0; 1321 err = register_filesystem(&sel_fs_type); 1322 if (!err) { 1323 selinuxfs_mount = kern_mount(&sel_fs_type); 1324 if (IS_ERR(selinuxfs_mount)) { 1325 printk(KERN_ERR "selinuxfs: could not mount!\n"); 1326 err = PTR_ERR(selinuxfs_mount); 1327 selinuxfs_mount = NULL; 1328 } 1329 } 1330 return err; 1331 } 1332 1333 __initcall(init_sel_fs); 1334 1335 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 1336 void exit_sel_fs(void) 1337 { 1338 unregister_filesystem(&sel_fs_type); 1339 } 1340 #endif 1341