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/mutex.h> 19 #include <linux/init.h> 20 #include <linux/string.h> 21 #include <linux/security.h> 22 #include <linux/major.h> 23 #include <linux/seq_file.h> 24 #include <linux/percpu.h> 25 #include <linux/audit.h> 26 #include <asm/uaccess.h> 27 #include <asm/semaphore.h> 28 29 /* selinuxfs pseudo filesystem for exporting the security policy API. 30 Based on the proc code and the fs/nfsd/nfsctl.c code. */ 31 32 #include "flask.h" 33 #include "avc.h" 34 #include "avc_ss.h" 35 #include "security.h" 36 #include "objsec.h" 37 #include "conditional.h" 38 39 unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE; 40 41 #ifdef CONFIG_SECURITY_SELINUX_ENABLE_SECMARK_DEFAULT 42 #define SELINUX_COMPAT_NET_VALUE 0 43 #else 44 #define SELINUX_COMPAT_NET_VALUE 1 45 #endif 46 47 int selinux_compat_net = SELINUX_COMPAT_NET_VALUE; 48 49 static int __init checkreqprot_setup(char *str) 50 { 51 selinux_checkreqprot = simple_strtoul(str,NULL,0) ? 1 : 0; 52 return 1; 53 } 54 __setup("checkreqprot=", checkreqprot_setup); 55 56 static int __init selinux_compat_net_setup(char *str) 57 { 58 selinux_compat_net = simple_strtoul(str,NULL,0) ? 1 : 0; 59 return 1; 60 } 61 __setup("selinux_compat_net=", selinux_compat_net_setup); 62 63 64 static DEFINE_MUTEX(sel_mutex); 65 66 /* global data for booleans */ 67 static struct dentry *bool_dir = NULL; 68 static int bool_num = 0; 69 static int *bool_pending_values = NULL; 70 71 extern void selnl_notify_setenforce(int val); 72 73 /* Check whether a task is allowed to use a security operation. */ 74 static int task_has_security(struct task_struct *tsk, 75 u32 perms) 76 { 77 struct task_security_struct *tsec; 78 79 tsec = tsk->security; 80 if (!tsec) 81 return -EACCES; 82 83 return avc_has_perm(tsec->sid, SECINITSID_SECURITY, 84 SECCLASS_SECURITY, perms, NULL); 85 } 86 87 enum sel_inos { 88 SEL_ROOT_INO = 2, 89 SEL_LOAD, /* load policy */ 90 SEL_ENFORCE, /* get or set enforcing status */ 91 SEL_CONTEXT, /* validate context */ 92 SEL_ACCESS, /* compute access decision */ 93 SEL_CREATE, /* compute create labeling decision */ 94 SEL_RELABEL, /* compute relabeling decision */ 95 SEL_USER, /* compute reachable user contexts */ 96 SEL_POLICYVERS, /* return policy version for this kernel */ 97 SEL_COMMIT_BOOLS, /* commit new boolean values */ 98 SEL_MLS, /* return if MLS policy is enabled */ 99 SEL_DISABLE, /* disable SELinux until next reboot */ 100 SEL_AVC, /* AVC management directory */ 101 SEL_MEMBER, /* compute polyinstantiation membership decision */ 102 SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */ 103 SEL_COMPAT_NET, /* whether to use old compat network packet controls */ 104 }; 105 106 #define TMPBUFLEN 12 107 static ssize_t sel_read_enforce(struct file *filp, char __user *buf, 108 size_t count, loff_t *ppos) 109 { 110 char tmpbuf[TMPBUFLEN]; 111 ssize_t length; 112 113 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing); 114 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 115 } 116 117 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 118 static ssize_t sel_write_enforce(struct file * file, const char __user * buf, 119 size_t count, loff_t *ppos) 120 121 { 122 char *page; 123 ssize_t length; 124 int new_value; 125 126 if (count >= PAGE_SIZE) 127 return -ENOMEM; 128 if (*ppos != 0) { 129 /* No partial writes. */ 130 return -EINVAL; 131 } 132 page = (char*)get_zeroed_page(GFP_KERNEL); 133 if (!page) 134 return -ENOMEM; 135 length = -EFAULT; 136 if (copy_from_user(page, buf, count)) 137 goto out; 138 139 length = -EINVAL; 140 if (sscanf(page, "%d", &new_value) != 1) 141 goto out; 142 143 if (new_value != selinux_enforcing) { 144 length = task_has_security(current, SECURITY__SETENFORCE); 145 if (length) 146 goto out; 147 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS, 148 "enforcing=%d old_enforcing=%d auid=%u", new_value, 149 selinux_enforcing, 150 audit_get_loginuid(current->audit_context)); 151 selinux_enforcing = new_value; 152 if (selinux_enforcing) 153 avc_ss_reset(0); 154 selnl_notify_setenforce(selinux_enforcing); 155 } 156 length = count; 157 out: 158 free_page((unsigned long) page); 159 return length; 160 } 161 #else 162 #define sel_write_enforce NULL 163 #endif 164 165 static struct file_operations sel_enforce_ops = { 166 .read = sel_read_enforce, 167 .write = sel_write_enforce, 168 }; 169 170 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 171 static ssize_t sel_write_disable(struct file * file, const char __user * buf, 172 size_t count, loff_t *ppos) 173 174 { 175 char *page; 176 ssize_t length; 177 int new_value; 178 extern int selinux_disable(void); 179 180 if (count >= PAGE_SIZE) 181 return -ENOMEM; 182 if (*ppos != 0) { 183 /* No partial writes. */ 184 return -EINVAL; 185 } 186 page = (char*)get_zeroed_page(GFP_KERNEL); 187 if (!page) 188 return -ENOMEM; 189 length = -EFAULT; 190 if (copy_from_user(page, buf, count)) 191 goto out; 192 193 length = -EINVAL; 194 if (sscanf(page, "%d", &new_value) != 1) 195 goto out; 196 197 if (new_value) { 198 length = selinux_disable(); 199 if (length < 0) 200 goto out; 201 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS, 202 "selinux=0 auid=%u", 203 audit_get_loginuid(current->audit_context)); 204 } 205 206 length = count; 207 out: 208 free_page((unsigned long) page); 209 return length; 210 } 211 #else 212 #define sel_write_disable NULL 213 #endif 214 215 static struct file_operations sel_disable_ops = { 216 .write = sel_write_disable, 217 }; 218 219 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf, 220 size_t count, loff_t *ppos) 221 { 222 char tmpbuf[TMPBUFLEN]; 223 ssize_t length; 224 225 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX); 226 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 227 } 228 229 static struct file_operations sel_policyvers_ops = { 230 .read = sel_read_policyvers, 231 }; 232 233 /* declaration for sel_write_load */ 234 static int sel_make_bools(void); 235 236 static ssize_t sel_read_mls(struct file *filp, char __user *buf, 237 size_t count, loff_t *ppos) 238 { 239 char tmpbuf[TMPBUFLEN]; 240 ssize_t length; 241 242 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_mls_enabled); 243 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 244 } 245 246 static struct file_operations sel_mls_ops = { 247 .read = sel_read_mls, 248 }; 249 250 static ssize_t sel_write_load(struct file * file, const char __user * buf, 251 size_t count, loff_t *ppos) 252 253 { 254 int ret; 255 ssize_t length; 256 void *data = NULL; 257 258 mutex_lock(&sel_mutex); 259 260 length = task_has_security(current, SECURITY__LOAD_POLICY); 261 if (length) 262 goto out; 263 264 if (*ppos != 0) { 265 /* No partial writes. */ 266 length = -EINVAL; 267 goto out; 268 } 269 270 if ((count > 64 * 1024 * 1024) 271 || (data = vmalloc(count)) == NULL) { 272 length = -ENOMEM; 273 goto out; 274 } 275 276 length = -EFAULT; 277 if (copy_from_user(data, buf, count) != 0) 278 goto out; 279 280 length = security_load_policy(data, count); 281 if (length) 282 goto out; 283 284 ret = sel_make_bools(); 285 if (ret) 286 length = ret; 287 else 288 length = count; 289 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD, 290 "policy loaded auid=%u", 291 audit_get_loginuid(current->audit_context)); 292 out: 293 mutex_unlock(&sel_mutex); 294 vfree(data); 295 return length; 296 } 297 298 static struct file_operations sel_load_ops = { 299 .write = sel_write_load, 300 }; 301 302 static ssize_t sel_write_context(struct file * file, char *buf, size_t size) 303 { 304 char *canon; 305 u32 sid, len; 306 ssize_t length; 307 308 length = task_has_security(current, SECURITY__CHECK_CONTEXT); 309 if (length) 310 return length; 311 312 length = security_context_to_sid(buf, size, &sid); 313 if (length < 0) 314 return length; 315 316 length = security_sid_to_context(sid, &canon, &len); 317 if (length < 0) 318 return length; 319 320 if (len > SIMPLE_TRANSACTION_LIMIT) { 321 printk(KERN_ERR "%s: context size (%u) exceeds payload " 322 "max\n", __FUNCTION__, len); 323 length = -ERANGE; 324 goto out; 325 } 326 327 memcpy(buf, canon, len); 328 length = len; 329 out: 330 kfree(canon); 331 return length; 332 } 333 334 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf, 335 size_t count, loff_t *ppos) 336 { 337 char tmpbuf[TMPBUFLEN]; 338 ssize_t length; 339 340 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot); 341 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 342 } 343 344 static ssize_t sel_write_checkreqprot(struct file * file, const char __user * buf, 345 size_t count, loff_t *ppos) 346 { 347 char *page; 348 ssize_t length; 349 unsigned int new_value; 350 351 length = task_has_security(current, SECURITY__SETCHECKREQPROT); 352 if (length) 353 return length; 354 355 if (count >= PAGE_SIZE) 356 return -ENOMEM; 357 if (*ppos != 0) { 358 /* No partial writes. */ 359 return -EINVAL; 360 } 361 page = (char*)get_zeroed_page(GFP_KERNEL); 362 if (!page) 363 return -ENOMEM; 364 length = -EFAULT; 365 if (copy_from_user(page, buf, count)) 366 goto out; 367 368 length = -EINVAL; 369 if (sscanf(page, "%u", &new_value) != 1) 370 goto out; 371 372 selinux_checkreqprot = new_value ? 1 : 0; 373 length = count; 374 out: 375 free_page((unsigned long) page); 376 return length; 377 } 378 static struct file_operations sel_checkreqprot_ops = { 379 .read = sel_read_checkreqprot, 380 .write = sel_write_checkreqprot, 381 }; 382 383 static ssize_t sel_read_compat_net(struct file *filp, char __user *buf, 384 size_t count, loff_t *ppos) 385 { 386 char tmpbuf[TMPBUFLEN]; 387 ssize_t length; 388 389 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_compat_net); 390 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 391 } 392 393 static ssize_t sel_write_compat_net(struct file * file, const char __user * buf, 394 size_t count, loff_t *ppos) 395 { 396 char *page; 397 ssize_t length; 398 int new_value; 399 400 length = task_has_security(current, SECURITY__LOAD_POLICY); 401 if (length) 402 return length; 403 404 if (count >= PAGE_SIZE) 405 return -ENOMEM; 406 if (*ppos != 0) { 407 /* No partial writes. */ 408 return -EINVAL; 409 } 410 page = (char*)get_zeroed_page(GFP_KERNEL); 411 if (!page) 412 return -ENOMEM; 413 length = -EFAULT; 414 if (copy_from_user(page, buf, count)) 415 goto out; 416 417 length = -EINVAL; 418 if (sscanf(page, "%d", &new_value) != 1) 419 goto out; 420 421 selinux_compat_net = new_value ? 1 : 0; 422 length = count; 423 out: 424 free_page((unsigned long) page); 425 return length; 426 } 427 static struct file_operations sel_compat_net_ops = { 428 .read = sel_read_compat_net, 429 .write = sel_write_compat_net, 430 }; 431 432 /* 433 * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c 434 */ 435 static ssize_t sel_write_access(struct file * file, char *buf, size_t size); 436 static ssize_t sel_write_create(struct file * file, char *buf, size_t size); 437 static ssize_t sel_write_relabel(struct file * file, char *buf, size_t size); 438 static ssize_t sel_write_user(struct file * file, char *buf, size_t size); 439 static ssize_t sel_write_member(struct file * file, char *buf, size_t size); 440 441 static ssize_t (*write_op[])(struct file *, char *, size_t) = { 442 [SEL_ACCESS] = sel_write_access, 443 [SEL_CREATE] = sel_write_create, 444 [SEL_RELABEL] = sel_write_relabel, 445 [SEL_USER] = sel_write_user, 446 [SEL_MEMBER] = sel_write_member, 447 [SEL_CONTEXT] = sel_write_context, 448 }; 449 450 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos) 451 { 452 ino_t ino = file->f_dentry->d_inode->i_ino; 453 char *data; 454 ssize_t rv; 455 456 if (ino >= ARRAY_SIZE(write_op) || !write_op[ino]) 457 return -EINVAL; 458 459 data = simple_transaction_get(file, buf, size); 460 if (IS_ERR(data)) 461 return PTR_ERR(data); 462 463 rv = write_op[ino](file, data, size); 464 if (rv>0) { 465 simple_transaction_set(file, rv); 466 rv = size; 467 } 468 return rv; 469 } 470 471 static struct file_operations transaction_ops = { 472 .write = selinux_transaction_write, 473 .read = simple_transaction_read, 474 .release = simple_transaction_release, 475 }; 476 477 /* 478 * payload - write methods 479 * If the method has a response, the response should be put in buf, 480 * and the length returned. Otherwise return 0 or and -error. 481 */ 482 483 static ssize_t sel_write_access(struct file * file, char *buf, size_t size) 484 { 485 char *scon, *tcon; 486 u32 ssid, tsid; 487 u16 tclass; 488 u32 req; 489 struct av_decision avd; 490 ssize_t length; 491 492 length = task_has_security(current, SECURITY__COMPUTE_AV); 493 if (length) 494 return length; 495 496 length = -ENOMEM; 497 scon = kzalloc(size+1, GFP_KERNEL); 498 if (!scon) 499 return length; 500 501 tcon = kzalloc(size+1, GFP_KERNEL); 502 if (!tcon) 503 goto out; 504 505 length = -EINVAL; 506 if (sscanf(buf, "%s %s %hu %x", scon, tcon, &tclass, &req) != 4) 507 goto out2; 508 509 length = security_context_to_sid(scon, strlen(scon)+1, &ssid); 510 if (length < 0) 511 goto out2; 512 length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid); 513 if (length < 0) 514 goto out2; 515 516 length = security_compute_av(ssid, tsid, tclass, req, &avd); 517 if (length < 0) 518 goto out2; 519 520 length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, 521 "%x %x %x %x %u", 522 avd.allowed, avd.decided, 523 avd.auditallow, avd.auditdeny, 524 avd.seqno); 525 out2: 526 kfree(tcon); 527 out: 528 kfree(scon); 529 return length; 530 } 531 532 static ssize_t sel_write_create(struct file * file, char *buf, size_t size) 533 { 534 char *scon, *tcon; 535 u32 ssid, tsid, newsid; 536 u16 tclass; 537 ssize_t length; 538 char *newcon; 539 u32 len; 540 541 length = task_has_security(current, SECURITY__COMPUTE_CREATE); 542 if (length) 543 return length; 544 545 length = -ENOMEM; 546 scon = kzalloc(size+1, GFP_KERNEL); 547 if (!scon) 548 return length; 549 550 tcon = kzalloc(size+1, GFP_KERNEL); 551 if (!tcon) 552 goto out; 553 554 length = -EINVAL; 555 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3) 556 goto out2; 557 558 length = security_context_to_sid(scon, strlen(scon)+1, &ssid); 559 if (length < 0) 560 goto out2; 561 length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid); 562 if (length < 0) 563 goto out2; 564 565 length = security_transition_sid(ssid, tsid, tclass, &newsid); 566 if (length < 0) 567 goto out2; 568 569 length = security_sid_to_context(newsid, &newcon, &len); 570 if (length < 0) 571 goto out2; 572 573 if (len > SIMPLE_TRANSACTION_LIMIT) { 574 printk(KERN_ERR "%s: context size (%u) exceeds payload " 575 "max\n", __FUNCTION__, len); 576 length = -ERANGE; 577 goto out3; 578 } 579 580 memcpy(buf, newcon, len); 581 length = len; 582 out3: 583 kfree(newcon); 584 out2: 585 kfree(tcon); 586 out: 587 kfree(scon); 588 return length; 589 } 590 591 static ssize_t sel_write_relabel(struct file * file, char *buf, size_t size) 592 { 593 char *scon, *tcon; 594 u32 ssid, tsid, newsid; 595 u16 tclass; 596 ssize_t length; 597 char *newcon; 598 u32 len; 599 600 length = task_has_security(current, SECURITY__COMPUTE_RELABEL); 601 if (length) 602 return length; 603 604 length = -ENOMEM; 605 scon = kzalloc(size+1, GFP_KERNEL); 606 if (!scon) 607 return length; 608 609 tcon = kzalloc(size+1, GFP_KERNEL); 610 if (!tcon) 611 goto out; 612 613 length = -EINVAL; 614 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3) 615 goto out2; 616 617 length = security_context_to_sid(scon, strlen(scon)+1, &ssid); 618 if (length < 0) 619 goto out2; 620 length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid); 621 if (length < 0) 622 goto out2; 623 624 length = security_change_sid(ssid, tsid, tclass, &newsid); 625 if (length < 0) 626 goto out2; 627 628 length = security_sid_to_context(newsid, &newcon, &len); 629 if (length < 0) 630 goto out2; 631 632 if (len > SIMPLE_TRANSACTION_LIMIT) { 633 length = -ERANGE; 634 goto out3; 635 } 636 637 memcpy(buf, newcon, len); 638 length = len; 639 out3: 640 kfree(newcon); 641 out2: 642 kfree(tcon); 643 out: 644 kfree(scon); 645 return length; 646 } 647 648 static ssize_t sel_write_user(struct file * file, char *buf, size_t size) 649 { 650 char *con, *user, *ptr; 651 u32 sid, *sids; 652 ssize_t length; 653 char *newcon; 654 int i, rc; 655 u32 len, nsids; 656 657 length = task_has_security(current, SECURITY__COMPUTE_USER); 658 if (length) 659 return length; 660 661 length = -ENOMEM; 662 con = kzalloc(size+1, GFP_KERNEL); 663 if (!con) 664 return length; 665 666 user = kzalloc(size+1, GFP_KERNEL); 667 if (!user) 668 goto out; 669 670 length = -EINVAL; 671 if (sscanf(buf, "%s %s", con, user) != 2) 672 goto out2; 673 674 length = security_context_to_sid(con, strlen(con)+1, &sid); 675 if (length < 0) 676 goto out2; 677 678 length = security_get_user_sids(sid, user, &sids, &nsids); 679 if (length < 0) 680 goto out2; 681 682 length = sprintf(buf, "%u", nsids) + 1; 683 ptr = buf + length; 684 for (i = 0; i < nsids; i++) { 685 rc = security_sid_to_context(sids[i], &newcon, &len); 686 if (rc) { 687 length = rc; 688 goto out3; 689 } 690 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) { 691 kfree(newcon); 692 length = -ERANGE; 693 goto out3; 694 } 695 memcpy(ptr, newcon, len); 696 kfree(newcon); 697 ptr += len; 698 length += len; 699 } 700 out3: 701 kfree(sids); 702 out2: 703 kfree(user); 704 out: 705 kfree(con); 706 return length; 707 } 708 709 static ssize_t sel_write_member(struct file * file, char *buf, size_t size) 710 { 711 char *scon, *tcon; 712 u32 ssid, tsid, newsid; 713 u16 tclass; 714 ssize_t length; 715 char *newcon; 716 u32 len; 717 718 length = task_has_security(current, SECURITY__COMPUTE_MEMBER); 719 if (length) 720 return length; 721 722 length = -ENOMEM; 723 scon = kzalloc(size+1, GFP_KERNEL); 724 if (!scon) 725 return length; 726 727 tcon = kzalloc(size+1, GFP_KERNEL); 728 if (!tcon) 729 goto out; 730 731 length = -EINVAL; 732 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3) 733 goto out2; 734 735 length = security_context_to_sid(scon, strlen(scon)+1, &ssid); 736 if (length < 0) 737 goto out2; 738 length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid); 739 if (length < 0) 740 goto out2; 741 742 length = security_member_sid(ssid, tsid, tclass, &newsid); 743 if (length < 0) 744 goto out2; 745 746 length = security_sid_to_context(newsid, &newcon, &len); 747 if (length < 0) 748 goto out2; 749 750 if (len > SIMPLE_TRANSACTION_LIMIT) { 751 printk(KERN_ERR "%s: context size (%u) exceeds payload " 752 "max\n", __FUNCTION__, len); 753 length = -ERANGE; 754 goto out3; 755 } 756 757 memcpy(buf, newcon, len); 758 length = len; 759 out3: 760 kfree(newcon); 761 out2: 762 kfree(tcon); 763 out: 764 kfree(scon); 765 return length; 766 } 767 768 static struct inode *sel_make_inode(struct super_block *sb, int mode) 769 { 770 struct inode *ret = new_inode(sb); 771 772 if (ret) { 773 ret->i_mode = mode; 774 ret->i_uid = ret->i_gid = 0; 775 ret->i_blksize = PAGE_CACHE_SIZE; 776 ret->i_blocks = 0; 777 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME; 778 } 779 return ret; 780 } 781 782 #define BOOL_INO_OFFSET 30 783 784 static ssize_t sel_read_bool(struct file *filep, char __user *buf, 785 size_t count, loff_t *ppos) 786 { 787 char *page = NULL; 788 ssize_t length; 789 ssize_t ret; 790 int cur_enforcing; 791 struct inode *inode; 792 793 mutex_lock(&sel_mutex); 794 795 ret = -EFAULT; 796 797 /* check to see if this file has been deleted */ 798 if (!filep->f_op) 799 goto out; 800 801 if (count > PAGE_SIZE) { 802 ret = -EINVAL; 803 goto out; 804 } 805 if (!(page = (char*)get_zeroed_page(GFP_KERNEL))) { 806 ret = -ENOMEM; 807 goto out; 808 } 809 810 inode = filep->f_dentry->d_inode; 811 cur_enforcing = security_get_bool_value(inode->i_ino - BOOL_INO_OFFSET); 812 if (cur_enforcing < 0) { 813 ret = cur_enforcing; 814 goto out; 815 } 816 817 length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing, 818 bool_pending_values[inode->i_ino - BOOL_INO_OFFSET]); 819 ret = simple_read_from_buffer(buf, count, ppos, page, length); 820 out: 821 mutex_unlock(&sel_mutex); 822 if (page) 823 free_page((unsigned long)page); 824 return ret; 825 } 826 827 static ssize_t sel_write_bool(struct file *filep, const char __user *buf, 828 size_t count, loff_t *ppos) 829 { 830 char *page = NULL; 831 ssize_t length = -EFAULT; 832 int new_value; 833 struct inode *inode; 834 835 mutex_lock(&sel_mutex); 836 837 length = task_has_security(current, SECURITY__SETBOOL); 838 if (length) 839 goto out; 840 841 /* check to see if this file has been deleted */ 842 if (!filep->f_op) 843 goto out; 844 845 if (count >= PAGE_SIZE) { 846 length = -ENOMEM; 847 goto out; 848 } 849 if (*ppos != 0) { 850 /* No partial writes. */ 851 goto out; 852 } 853 page = (char*)get_zeroed_page(GFP_KERNEL); 854 if (!page) { 855 length = -ENOMEM; 856 goto out; 857 } 858 859 if (copy_from_user(page, buf, count)) 860 goto out; 861 862 length = -EINVAL; 863 if (sscanf(page, "%d", &new_value) != 1) 864 goto out; 865 866 if (new_value) 867 new_value = 1; 868 869 inode = filep->f_dentry->d_inode; 870 bool_pending_values[inode->i_ino - BOOL_INO_OFFSET] = new_value; 871 length = count; 872 873 out: 874 mutex_unlock(&sel_mutex); 875 if (page) 876 free_page((unsigned long) page); 877 return length; 878 } 879 880 static struct file_operations sel_bool_ops = { 881 .read = sel_read_bool, 882 .write = sel_write_bool, 883 }; 884 885 static ssize_t sel_commit_bools_write(struct file *filep, 886 const char __user *buf, 887 size_t count, loff_t *ppos) 888 { 889 char *page = NULL; 890 ssize_t length = -EFAULT; 891 int new_value; 892 893 mutex_lock(&sel_mutex); 894 895 length = task_has_security(current, SECURITY__SETBOOL); 896 if (length) 897 goto out; 898 899 /* check to see if this file has been deleted */ 900 if (!filep->f_op) 901 goto out; 902 903 if (count >= PAGE_SIZE) { 904 length = -ENOMEM; 905 goto out; 906 } 907 if (*ppos != 0) { 908 /* No partial writes. */ 909 goto out; 910 } 911 page = (char*)get_zeroed_page(GFP_KERNEL); 912 if (!page) { 913 length = -ENOMEM; 914 goto out; 915 } 916 917 if (copy_from_user(page, buf, count)) 918 goto out; 919 920 length = -EINVAL; 921 if (sscanf(page, "%d", &new_value) != 1) 922 goto out; 923 924 if (new_value && bool_pending_values) { 925 security_set_bools(bool_num, bool_pending_values); 926 } 927 928 length = count; 929 930 out: 931 mutex_unlock(&sel_mutex); 932 if (page) 933 free_page((unsigned long) page); 934 return length; 935 } 936 937 static struct file_operations sel_commit_bools_ops = { 938 .write = sel_commit_bools_write, 939 }; 940 941 /* delete booleans - partial revoke() from 942 * fs/proc/generic.c proc_kill_inodes */ 943 static void sel_remove_bools(struct dentry *de) 944 { 945 struct list_head *p, *node; 946 struct super_block *sb = de->d_sb; 947 948 spin_lock(&dcache_lock); 949 node = de->d_subdirs.next; 950 while (node != &de->d_subdirs) { 951 struct dentry *d = list_entry(node, struct dentry, d_u.d_child); 952 list_del_init(node); 953 954 if (d->d_inode) { 955 d = dget_locked(d); 956 spin_unlock(&dcache_lock); 957 d_delete(d); 958 simple_unlink(de->d_inode, d); 959 dput(d); 960 spin_lock(&dcache_lock); 961 } 962 node = de->d_subdirs.next; 963 } 964 965 spin_unlock(&dcache_lock); 966 967 file_list_lock(); 968 list_for_each(p, &sb->s_files) { 969 struct file * filp = list_entry(p, struct file, f_u.fu_list); 970 struct dentry * dentry = filp->f_dentry; 971 972 if (dentry->d_parent != de) { 973 continue; 974 } 975 filp->f_op = NULL; 976 } 977 file_list_unlock(); 978 } 979 980 #define BOOL_DIR_NAME "booleans" 981 982 static int sel_make_bools(void) 983 { 984 int i, ret = 0; 985 ssize_t len; 986 struct dentry *dentry = NULL; 987 struct dentry *dir = bool_dir; 988 struct inode *inode = NULL; 989 struct inode_security_struct *isec; 990 char **names = NULL, *page; 991 int num; 992 int *values = NULL; 993 u32 sid; 994 995 /* remove any existing files */ 996 kfree(bool_pending_values); 997 bool_pending_values = NULL; 998 999 sel_remove_bools(dir); 1000 1001 if (!(page = (char*)get_zeroed_page(GFP_KERNEL))) 1002 return -ENOMEM; 1003 1004 ret = security_get_bools(&num, &names, &values); 1005 if (ret != 0) 1006 goto out; 1007 1008 for (i = 0; i < num; i++) { 1009 dentry = d_alloc_name(dir, names[i]); 1010 if (!dentry) { 1011 ret = -ENOMEM; 1012 goto err; 1013 } 1014 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR); 1015 if (!inode) { 1016 ret = -ENOMEM; 1017 goto err; 1018 } 1019 1020 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]); 1021 if (len < 0) { 1022 ret = -EINVAL; 1023 goto err; 1024 } else if (len >= PAGE_SIZE) { 1025 ret = -ENAMETOOLONG; 1026 goto err; 1027 } 1028 isec = (struct inode_security_struct*)inode->i_security; 1029 if ((ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid))) 1030 goto err; 1031 isec->sid = sid; 1032 isec->initialized = 1; 1033 inode->i_fop = &sel_bool_ops; 1034 inode->i_ino = i + BOOL_INO_OFFSET; 1035 d_add(dentry, inode); 1036 } 1037 bool_num = num; 1038 bool_pending_values = values; 1039 out: 1040 free_page((unsigned long)page); 1041 if (names) { 1042 for (i = 0; i < num; i++) 1043 kfree(names[i]); 1044 kfree(names); 1045 } 1046 return ret; 1047 err: 1048 kfree(values); 1049 sel_remove_bools(dir); 1050 ret = -ENOMEM; 1051 goto out; 1052 } 1053 1054 #define NULL_FILE_NAME "null" 1055 1056 struct dentry *selinux_null = NULL; 1057 1058 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf, 1059 size_t count, loff_t *ppos) 1060 { 1061 char tmpbuf[TMPBUFLEN]; 1062 ssize_t length; 1063 1064 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold); 1065 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1066 } 1067 1068 static ssize_t sel_write_avc_cache_threshold(struct file * file, 1069 const char __user * buf, 1070 size_t count, loff_t *ppos) 1071 1072 { 1073 char *page; 1074 ssize_t ret; 1075 int new_value; 1076 1077 if (count >= PAGE_SIZE) { 1078 ret = -ENOMEM; 1079 goto out; 1080 } 1081 1082 if (*ppos != 0) { 1083 /* No partial writes. */ 1084 ret = -EINVAL; 1085 goto out; 1086 } 1087 1088 page = (char*)get_zeroed_page(GFP_KERNEL); 1089 if (!page) { 1090 ret = -ENOMEM; 1091 goto out; 1092 } 1093 1094 if (copy_from_user(page, buf, count)) { 1095 ret = -EFAULT; 1096 goto out_free; 1097 } 1098 1099 if (sscanf(page, "%u", &new_value) != 1) { 1100 ret = -EINVAL; 1101 goto out; 1102 } 1103 1104 if (new_value != avc_cache_threshold) { 1105 ret = task_has_security(current, SECURITY__SETSECPARAM); 1106 if (ret) 1107 goto out_free; 1108 avc_cache_threshold = new_value; 1109 } 1110 ret = count; 1111 out_free: 1112 free_page((unsigned long)page); 1113 out: 1114 return ret; 1115 } 1116 1117 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf, 1118 size_t count, loff_t *ppos) 1119 { 1120 char *page; 1121 ssize_t ret = 0; 1122 1123 page = (char *)__get_free_page(GFP_KERNEL); 1124 if (!page) { 1125 ret = -ENOMEM; 1126 goto out; 1127 } 1128 ret = avc_get_hash_stats(page); 1129 if (ret >= 0) 1130 ret = simple_read_from_buffer(buf, count, ppos, page, ret); 1131 free_page((unsigned long)page); 1132 out: 1133 return ret; 1134 } 1135 1136 static struct file_operations sel_avc_cache_threshold_ops = { 1137 .read = sel_read_avc_cache_threshold, 1138 .write = sel_write_avc_cache_threshold, 1139 }; 1140 1141 static struct file_operations sel_avc_hash_stats_ops = { 1142 .read = sel_read_avc_hash_stats, 1143 }; 1144 1145 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS 1146 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx) 1147 { 1148 int cpu; 1149 1150 for (cpu = *idx; cpu < NR_CPUS; ++cpu) { 1151 if (!cpu_possible(cpu)) 1152 continue; 1153 *idx = cpu + 1; 1154 return &per_cpu(avc_cache_stats, cpu); 1155 } 1156 return NULL; 1157 } 1158 1159 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos) 1160 { 1161 loff_t n = *pos - 1; 1162 1163 if (*pos == 0) 1164 return SEQ_START_TOKEN; 1165 1166 return sel_avc_get_stat_idx(&n); 1167 } 1168 1169 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos) 1170 { 1171 return sel_avc_get_stat_idx(pos); 1172 } 1173 1174 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v) 1175 { 1176 struct avc_cache_stats *st = v; 1177 1178 if (v == SEQ_START_TOKEN) 1179 seq_printf(seq, "lookups hits misses allocations reclaims " 1180 "frees\n"); 1181 else 1182 seq_printf(seq, "%u %u %u %u %u %u\n", st->lookups, 1183 st->hits, st->misses, st->allocations, 1184 st->reclaims, st->frees); 1185 return 0; 1186 } 1187 1188 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v) 1189 { } 1190 1191 static struct seq_operations sel_avc_cache_stats_seq_ops = { 1192 .start = sel_avc_stats_seq_start, 1193 .next = sel_avc_stats_seq_next, 1194 .show = sel_avc_stats_seq_show, 1195 .stop = sel_avc_stats_seq_stop, 1196 }; 1197 1198 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file) 1199 { 1200 return seq_open(file, &sel_avc_cache_stats_seq_ops); 1201 } 1202 1203 static struct file_operations sel_avc_cache_stats_ops = { 1204 .open = sel_open_avc_cache_stats, 1205 .read = seq_read, 1206 .llseek = seq_lseek, 1207 .release = seq_release, 1208 }; 1209 #endif 1210 1211 static int sel_make_avc_files(struct dentry *dir) 1212 { 1213 int i, ret = 0; 1214 static struct tree_descr files[] = { 1215 { "cache_threshold", 1216 &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR }, 1217 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO }, 1218 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS 1219 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO }, 1220 #endif 1221 }; 1222 1223 for (i = 0; i < ARRAY_SIZE(files); i++) { 1224 struct inode *inode; 1225 struct dentry *dentry; 1226 1227 dentry = d_alloc_name(dir, files[i].name); 1228 if (!dentry) { 1229 ret = -ENOMEM; 1230 goto out; 1231 } 1232 1233 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode); 1234 if (!inode) { 1235 ret = -ENOMEM; 1236 goto out; 1237 } 1238 inode->i_fop = files[i].ops; 1239 d_add(dentry, inode); 1240 } 1241 out: 1242 return ret; 1243 } 1244 1245 static int sel_make_dir(struct inode *dir, struct dentry *dentry) 1246 { 1247 int ret = 0; 1248 struct inode *inode; 1249 1250 inode = sel_make_inode(dir->i_sb, S_IFDIR | S_IRUGO | S_IXUGO); 1251 if (!inode) { 1252 ret = -ENOMEM; 1253 goto out; 1254 } 1255 inode->i_op = &simple_dir_inode_operations; 1256 inode->i_fop = &simple_dir_operations; 1257 /* directory inodes start off with i_nlink == 2 (for "." entry) */ 1258 inode->i_nlink++; 1259 d_add(dentry, inode); 1260 /* bump link count on parent directory, too */ 1261 dir->i_nlink++; 1262 out: 1263 return ret; 1264 } 1265 1266 static int sel_fill_super(struct super_block * sb, void * data, int silent) 1267 { 1268 int ret; 1269 struct dentry *dentry; 1270 struct inode *inode, *root_inode; 1271 struct inode_security_struct *isec; 1272 1273 static struct tree_descr selinux_files[] = { 1274 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR}, 1275 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR}, 1276 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO}, 1277 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO}, 1278 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO}, 1279 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO}, 1280 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO}, 1281 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO}, 1282 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR}, 1283 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO}, 1284 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR}, 1285 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO}, 1286 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR}, 1287 [SEL_COMPAT_NET] = {"compat_net", &sel_compat_net_ops, S_IRUGO|S_IWUSR}, 1288 /* last one */ {""} 1289 }; 1290 ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files); 1291 if (ret) 1292 goto err; 1293 1294 root_inode = sb->s_root->d_inode; 1295 1296 dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME); 1297 if (!dentry) { 1298 ret = -ENOMEM; 1299 goto err; 1300 } 1301 1302 ret = sel_make_dir(root_inode, dentry); 1303 if (ret) 1304 goto err; 1305 1306 bool_dir = dentry; 1307 1308 dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME); 1309 if (!dentry) { 1310 ret = -ENOMEM; 1311 goto err; 1312 } 1313 1314 inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO); 1315 if (!inode) { 1316 ret = -ENOMEM; 1317 goto err; 1318 } 1319 isec = (struct inode_security_struct*)inode->i_security; 1320 isec->sid = SECINITSID_DEVNULL; 1321 isec->sclass = SECCLASS_CHR_FILE; 1322 isec->initialized = 1; 1323 1324 init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3)); 1325 d_add(dentry, inode); 1326 selinux_null = dentry; 1327 1328 dentry = d_alloc_name(sb->s_root, "avc"); 1329 if (!dentry) { 1330 ret = -ENOMEM; 1331 goto err; 1332 } 1333 1334 ret = sel_make_dir(root_inode, dentry); 1335 if (ret) 1336 goto err; 1337 1338 ret = sel_make_avc_files(dentry); 1339 if (ret) 1340 goto err; 1341 out: 1342 return ret; 1343 err: 1344 printk(KERN_ERR "%s: failed while creating inodes\n", __FUNCTION__); 1345 goto out; 1346 } 1347 1348 static struct super_block *sel_get_sb(struct file_system_type *fs_type, 1349 int flags, const char *dev_name, void *data) 1350 { 1351 return get_sb_single(fs_type, flags, data, sel_fill_super); 1352 } 1353 1354 static struct file_system_type sel_fs_type = { 1355 .name = "selinuxfs", 1356 .get_sb = sel_get_sb, 1357 .kill_sb = kill_litter_super, 1358 }; 1359 1360 struct vfsmount *selinuxfs_mount; 1361 1362 static int __init init_sel_fs(void) 1363 { 1364 int err; 1365 1366 if (!selinux_enabled) 1367 return 0; 1368 err = register_filesystem(&sel_fs_type); 1369 if (!err) { 1370 selinuxfs_mount = kern_mount(&sel_fs_type); 1371 if (IS_ERR(selinuxfs_mount)) { 1372 printk(KERN_ERR "selinuxfs: could not mount!\n"); 1373 err = PTR_ERR(selinuxfs_mount); 1374 selinuxfs_mount = NULL; 1375 } 1376 } 1377 return err; 1378 } 1379 1380 __initcall(init_sel_fs); 1381 1382 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 1383 void exit_sel_fs(void) 1384 { 1385 unregister_filesystem(&sel_fs_type); 1386 } 1387 #endif 1388