security/selinux/selinuxfs.c

   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         "extended_socket_class",
  49         "always_check_network",
  50         "cgroup_seclabel"
  51 };
  52
  53 unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
  54
  55 static int __init checkreqprot_setup(char *str)
  56 {
  57         unsigned long checkreqprot;
  58         if (!kstrtoul(str, 0, &checkreqprot))
  59                 selinux_checkreqprot = checkreqprot ? 1 : 0;
  60         return 1;
  61 }
  62 __setup("checkreqprot=", checkreqprot_setup);
  63
  64 static DEFINE_MUTEX(sel_mutex);
  65
  66 /* global data for booleans */
  67 static struct dentry *bool_dir;
  68 static int bool_num;
  69 static char **bool_pending_names;
  70 static int *bool_pending_values;
  71
  72 /* global data for classes */
  73 static struct dentry *class_dir;
  74 static unsigned long last_class_ino;
  75
  76 static char policy_opened;
  77
  78 /* global data for policy capabilities */
  79 static struct dentry *policycap_dir;
  80
  81 enum sel_inos {
  82         SEL_ROOT_INO = 2,
  83         SEL_LOAD,       /* load policy */
  84         SEL_ENFORCE,    /* get or set enforcing status */
  85         SEL_CONTEXT,    /* validate context */
  86         SEL_ACCESS,     /* compute access decision */
  87         SEL_CREATE,     /* compute create labeling decision */
  88         SEL_RELABEL,    /* compute relabeling decision */
  89         SEL_USER,       /* compute reachable user contexts */
  90         SEL_POLICYVERS, /* return policy version for this kernel */
  91         SEL_COMMIT_BOOLS, /* commit new boolean values */
  92         SEL_MLS,        /* return if MLS policy is enabled */
  93         SEL_DISABLE,    /* disable SELinux until next reboot */
  94         SEL_MEMBER,     /* compute polyinstantiation membership decision */
  95         SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
  96         SEL_COMPAT_NET, /* whether to use old compat network packet controls */
  97         SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */
  98         SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */
  99         SEL_STATUS,     /* export current status using mmap() */
 100         SEL_POLICY,     /* allow userspace to read the in kernel policy */
 101         SEL_VALIDATE_TRANS, /* compute validatetrans decision */
 102         SEL_INO_NEXT,   /* The next inode number to use */
 103 };
 104
 105 static unsigned long sel_last_ino = SEL_INO_NEXT - 1;
 106
 107 #define SEL_INITCON_INO_OFFSET          0x01000000
 108 #define SEL_BOOL_INO_OFFSET             0x02000000
 109 #define SEL_CLASS_INO_OFFSET            0x04000000
 110 #define SEL_POLICYCAP_INO_OFFSET        0x08000000
 111 #define SEL_INO_MASK                    0x00ffffff
 112
 113 #define TMPBUFLEN       12
 114 static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
 115                                 size_t count, loff_t *ppos)
 116 {
 117         char tmpbuf[TMPBUFLEN];
 118         ssize_t length;
 119
 120         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing);
 121         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 122 }
 123
 124 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 125 static ssize_t sel_write_enforce(struct file *file, const char __user *buf,
 126                                  size_t count, loff_t *ppos)
 127
 128 {
 129         char *page = NULL;
 130         ssize_t length;
 131         int new_value;
 132
 133         if (count >= PAGE_SIZE)
 134                 return -ENOMEM;
 135
 136         /* No partial writes. */
 137         if (*ppos != 0)
 138                 return -EINVAL;
 139
 140         page = memdup_user_nul(buf, count);
 141         if (IS_ERR(page))
 142                 return PTR_ERR(page);
 143
 144         length = -EINVAL;
 145         if (sscanf(page, "%d", &new_value) != 1)
 146                 goto out;
 147
 148         new_value = !!new_value;
 149
 150         if (new_value != selinux_enforcing) {
 151                 length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 152                                       SECCLASS_SECURITY, SECURITY__SETENFORCE,
 153                                       NULL);
 154                 if (length)
 155                         goto out;
 156                 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
 157                         "enforcing=%d old_enforcing=%d auid=%u ses=%u",
 158                         new_value, selinux_enforcing,
 159                         from_kuid(&init_user_ns, audit_get_loginuid(current)),
 160                         audit_get_sessionid(current));
 161                 selinux_enforcing = new_value;
 162                 if (selinux_enforcing)
 163                         avc_ss_reset(0);
 164                 selnl_notify_setenforce(selinux_enforcing);
 165                 selinux_status_update_setenforce(selinux_enforcing);
 166         }
 167         length = count;
 168 out:
 169         kfree(page);
 170         return length;
 171 }
 172 #else
 173 #define sel_write_enforce NULL
 174 #endif
 175
 176 static const struct file_operations sel_enforce_ops = {
 177         .read           = sel_read_enforce,
 178         .write          = sel_write_enforce,
 179         .llseek         = generic_file_llseek,
 180 };
 181
 182 static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
 183                                         size_t count, loff_t *ppos)
 184 {
 185         char tmpbuf[TMPBUFLEN];
 186         ssize_t length;
 187         ino_t ino = file_inode(filp)->i_ino;
 188         int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ?
 189                 security_get_reject_unknown() : !security_get_allow_unknown();
 190
 191         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown);
 192         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 193 }
 194
 195 static const struct file_operations sel_handle_unknown_ops = {
 196         .read           = sel_read_handle_unknown,
 197         .llseek         = generic_file_llseek,
 198 };
 199
 200 static int sel_open_handle_status(struct inode *inode, struct file *filp)
 201 {
 202         struct page    *status = selinux_kernel_status_page();
 203
 204         if (!status)
 205                 return -ENOMEM;
 206
 207         filp->private_data = status;
 208
 209         return 0;
 210 }
 211
 212 static ssize_t sel_read_handle_status(struct file *filp, char __user *buf,
 213                                       size_t count, loff_t *ppos)
 214 {
 215         struct page    *status = filp->private_data;
 216
 217         BUG_ON(!status);
 218
 219         return simple_read_from_buffer(buf, count, ppos,
 220                                        page_address(status),
 221                                        sizeof(struct selinux_kernel_status));
 222 }
 223
 224 static int sel_mmap_handle_status(struct file *filp,
 225                                   struct vm_area_struct *vma)
 226 {
 227         struct page    *status = filp->private_data;
 228         unsigned long   size = vma->vm_end - vma->vm_start;
 229
 230         BUG_ON(!status);
 231
 232         /* only allows one page from the head */
 233         if (vma->vm_pgoff > 0 || size != PAGE_SIZE)
 234                 return -EIO;
 235         /* disallow writable mapping */
 236         if (vma->vm_flags & VM_WRITE)
 237                 return -EPERM;
 238         /* disallow mprotect() turns it into writable */
 239         vma->vm_flags &= ~VM_MAYWRITE;
 240
 241         return remap_pfn_range(vma, vma->vm_start,
 242                                page_to_pfn(status),
 243                                size, vma->vm_page_prot);
 244 }
 245
 246 static const struct file_operations sel_handle_status_ops = {
 247         .open           = sel_open_handle_status,
 248         .read           = sel_read_handle_status,
 249         .mmap           = sel_mmap_handle_status,
 250         .llseek         = generic_file_llseek,
 251 };
 252
 253 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
 254 static ssize_t sel_write_disable(struct file *file, const char __user *buf,
 255                                  size_t count, loff_t *ppos)
 256
 257 {
 258         char *page;
 259         ssize_t length;
 260         int new_value;
 261
 262         if (count >= PAGE_SIZE)
 263                 return -ENOMEM;
 264
 265         /* No partial writes. */
 266         if (*ppos != 0)
 267                 return -EINVAL;
 268
 269         page = memdup_user_nul(buf, count);
 270         if (IS_ERR(page))
 271                 return PTR_ERR(page);
 272
 273         length = -EINVAL;
 274         if (sscanf(page, "%d", &new_value) != 1)
 275                 goto out;
 276
 277         if (new_value) {
 278                 length = selinux_disable();
 279                 if (length)
 280                         goto out;
 281                 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
 282                         "selinux=0 auid=%u ses=%u",
 283                         from_kuid(&init_user_ns, audit_get_loginuid(current)),
 284                         audit_get_sessionid(current));
 285         }
 286
 287         length = count;
 288 out:
 289         kfree(page);
 290         return length;
 291 }
 292 #else
 293 #define sel_write_disable NULL
 294 #endif
 295
 296 static const struct file_operations sel_disable_ops = {
 297         .write          = sel_write_disable,
 298         .llseek         = generic_file_llseek,
 299 };
 300
 301 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
 302                                    size_t count, loff_t *ppos)
 303 {
 304         char tmpbuf[TMPBUFLEN];
 305         ssize_t length;
 306
 307         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
 308         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 309 }
 310
 311 static const struct file_operations sel_policyvers_ops = {
 312         .read           = sel_read_policyvers,
 313         .llseek         = generic_file_llseek,
 314 };
 315
 316 /* declaration for sel_write_load */
 317 static int sel_make_bools(void);
 318 static int sel_make_classes(void);
 319 static int sel_make_policycap(void);
 320
 321 /* declaration for sel_make_class_dirs */
 322 static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
 323                         unsigned long *ino);
 324
 325 static ssize_t sel_read_mls(struct file *filp, char __user *buf,
 326                                 size_t count, loff_t *ppos)
 327 {
 328         char tmpbuf[TMPBUFLEN];
 329         ssize_t length;
 330
 331         length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
 332                            security_mls_enabled());
 333         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 334 }
 335
 336 static const struct file_operations sel_mls_ops = {
 337         .read           = sel_read_mls,
 338         .llseek         = generic_file_llseek,
 339 };
 340
 341 struct policy_load_memory {
 342         size_t len;
 343         void *data;
 344 };
 345
 346 static int sel_open_policy(struct inode *inode, struct file *filp)
 347 {
 348         struct policy_load_memory *plm = NULL;
 349         int rc;
 350
 351         BUG_ON(filp->private_data);
 352
 353         mutex_lock(&sel_mutex);
 354
 355         rc = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 356                           SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
 357         if (rc)
 358                 goto err;
 359
 360         rc = -EBUSY;
 361         if (policy_opened)
 362                 goto err;
 363
 364         rc = -ENOMEM;
 365         plm = kzalloc(sizeof(*plm), GFP_KERNEL);
 366         if (!plm)
 367                 goto err;
 368
 369         if (i_size_read(inode) != security_policydb_len()) {
 370                 inode_lock(inode);
 371                 i_size_write(inode, security_policydb_len());
 372                 inode_unlock(inode);
 373         }
 374
 375         rc = security_read_policy(&plm->data, &plm->len);
 376         if (rc)
 377                 goto err;
 378
 379         policy_opened = 1;
 380
 381         filp->private_data = plm;
 382
 383         mutex_unlock(&sel_mutex);
 384
 385         return 0;
 386 err:
 387         mutex_unlock(&sel_mutex);
 388
 389         if (plm)
 390                 vfree(plm->data);
 391         kfree(plm);
 392         return rc;
 393 }
 394
 395 static int sel_release_policy(struct inode *inode, struct file *filp)
 396 {
 397         struct policy_load_memory *plm = filp->private_data;
 398
 399         BUG_ON(!plm);
 400
 401         policy_opened = 0;
 402
 403         vfree(plm->data);
 404         kfree(plm);
 405
 406         return 0;
 407 }
 408
 409 static ssize_t sel_read_policy(struct file *filp, char __user *buf,
 410                                size_t count, loff_t *ppos)
 411 {
 412         struct policy_load_memory *plm = filp->private_data;
 413         int ret;
 414
 415         mutex_lock(&sel_mutex);
 416
 417         ret = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 418                           SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
 419         if (ret)
 420                 goto out;
 421
 422         ret = simple_read_from_buffer(buf, count, ppos, plm->data, plm->len);
 423 out:
 424         mutex_unlock(&sel_mutex);
 425         return ret;
 426 }
 427
 428 static int sel_mmap_policy_fault(struct vm_fault *vmf)
 429 {
 430         struct policy_load_memory *plm = vmf->vma->vm_file->private_data;
 431         unsigned long offset;
 432         struct page *page;
 433
 434         if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE))
 435                 return VM_FAULT_SIGBUS;
 436
 437         offset = vmf->pgoff << PAGE_SHIFT;
 438         if (offset >= roundup(plm->len, PAGE_SIZE))
 439                 return VM_FAULT_SIGBUS;
 440
 441         page = vmalloc_to_page(plm->data + offset);
 442         get_page(page);
 443
 444         vmf->page = page;
 445
 446         return 0;
 447 }
 448
 449 static const struct vm_operations_struct sel_mmap_policy_ops = {
 450         .fault = sel_mmap_policy_fault,
 451         .page_mkwrite = sel_mmap_policy_fault,
 452 };
 453
 454 static int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma)
 455 {
 456         if (vma->vm_flags & VM_SHARED) {
 457                 /* do not allow mprotect to make mapping writable */
 458                 vma->vm_flags &= ~VM_MAYWRITE;
 459
 460                 if (vma->vm_flags & VM_WRITE)
 461                         return -EACCES;
 462         }
 463
 464         vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
 465         vma->vm_ops = &sel_mmap_policy_ops;
 466
 467         return 0;
 468 }
 469
 470 static const struct file_operations sel_policy_ops = {
 471         .open           = sel_open_policy,
 472         .read           = sel_read_policy,
 473         .mmap           = sel_mmap_policy,
 474         .release        = sel_release_policy,
 475         .llseek         = generic_file_llseek,
 476 };
 477
 478 static ssize_t sel_write_load(struct file *file, const char __user *buf,
 479                               size_t count, loff_t *ppos)
 480
 481 {
 482         ssize_t length;
 483         void *data = NULL;
 484
 485         mutex_lock(&sel_mutex);
 486
 487         length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 488                               SECCLASS_SECURITY, SECURITY__LOAD_POLICY, NULL);
 489         if (length)
 490                 goto out;
 491
 492         /* No partial writes. */
 493         length = -EINVAL;
 494         if (*ppos != 0)
 495                 goto out;
 496
 497         length = -EFBIG;
 498         if (count > 64 * 1024 * 1024)
 499                 goto out;
 500
 501         length = -ENOMEM;
 502         data = vmalloc(count);
 503         if (!data)
 504                 goto out;
 505
 506         length = -EFAULT;
 507         if (copy_from_user(data, buf, count) != 0)
 508                 goto out;
 509
 510         length = security_load_policy(data, count);
 511         if (length) {
 512                 pr_warn_ratelimited("SELinux: failed to load policy\n");
 513                 goto out;
 514         }
 515
 516         length = sel_make_bools();
 517         if (length) {
 518                 pr_err("SELinux: failed to load policy booleans\n");
 519                 goto out1;
 520         }
 521
 522         length = sel_make_classes();
 523         if (length) {
 524                 pr_err("SELinux: failed to load policy classes\n");
 525                 goto out1;
 526         }
 527
 528         length = sel_make_policycap();
 529         if (length) {
 530                 pr_err("SELinux: failed to load policy capabilities\n");
 531                 goto out1;
 532         }
 533
 534         length = count;
 535
 536 out1:
 537         audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
 538                 "policy loaded auid=%u ses=%u",
 539                 from_kuid(&init_user_ns, audit_get_loginuid(current)),
 540                 audit_get_sessionid(current));
 541 out:
 542         mutex_unlock(&sel_mutex);
 543         vfree(data);
 544         return length;
 545 }
 546
 547 static const struct file_operations sel_load_ops = {
 548         .write          = sel_write_load,
 549         .llseek         = generic_file_llseek,
 550 };
 551
 552 static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
 553 {
 554         char *canon = NULL;
 555         u32 sid, len;
 556         ssize_t length;
 557
 558         length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 559                               SECCLASS_SECURITY, SECURITY__CHECK_CONTEXT, NULL);
 560         if (length)
 561                 goto out;
 562
 563         length = security_context_to_sid(buf, size, &sid, GFP_KERNEL);
 564         if (length)
 565                 goto out;
 566
 567         length = security_sid_to_context(sid, &canon, &len);
 568         if (length)
 569                 goto out;
 570
 571         length = -ERANGE;
 572         if (len > SIMPLE_TRANSACTION_LIMIT) {
 573                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
 574                         "payload max\n", __func__, len);
 575                 goto out;
 576         }
 577
 578         memcpy(buf, canon, len);
 579         length = len;
 580 out:
 581         kfree(canon);
 582         return length;
 583 }
 584
 585 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
 586                                      size_t count, loff_t *ppos)
 587 {
 588         char tmpbuf[TMPBUFLEN];
 589         ssize_t length;
 590
 591         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot);
 592         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 593 }
 594
 595 static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
 596                                       size_t count, loff_t *ppos)
 597 {
 598         char *page;
 599         ssize_t length;
 600         unsigned int new_value;
 601
 602         length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 603                               SECCLASS_SECURITY, SECURITY__SETCHECKREQPROT,
 604                               NULL);
 605         if (length)
 606                 return length;
 607
 608         if (count >= PAGE_SIZE)
 609                 return -ENOMEM;
 610
 611         /* No partial writes. */
 612         if (*ppos != 0)
 613                 return -EINVAL;
 614
 615         page = memdup_user_nul(buf, count);
 616         if (IS_ERR(page))
 617                 return PTR_ERR(page);
 618
 619         length = -EINVAL;
 620         if (sscanf(page, "%u", &new_value) != 1)
 621                 goto out;
 622
 623         selinux_checkreqprot = new_value ? 1 : 0;
 624         length = count;
 625 out:
 626         kfree(page);
 627         return length;
 628 }
 629 static const struct file_operations sel_checkreqprot_ops = {
 630         .read           = sel_read_checkreqprot,
 631         .write          = sel_write_checkreqprot,
 632         .llseek         = generic_file_llseek,
 633 };
 634
 635 static ssize_t sel_write_validatetrans(struct file *file,
 636                                         const char __user *buf,
 637                                         size_t count, loff_t *ppos)
 638 {
 639         char *oldcon = NULL, *newcon = NULL, *taskcon = NULL;
 640         char *req = NULL;
 641         u32 osid, nsid, tsid;
 642         u16 tclass;
 643         int rc;
 644
 645         rc = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 646                           SECCLASS_SECURITY, SECURITY__VALIDATE_TRANS, NULL);
 647         if (rc)
 648                 goto out;
 649
 650         rc = -ENOMEM;
 651         if (count >= PAGE_SIZE)
 652                 goto out;
 653
 654         /* No partial writes. */
 655         rc = -EINVAL;
 656         if (*ppos != 0)
 657                 goto out;
 658
 659         rc = -ENOMEM;
 660         req = kzalloc(count + 1, GFP_KERNEL);
 661         if (!req)
 662                 goto out;
 663
 664         rc = -EFAULT;
 665         if (copy_from_user(req, buf, count))
 666                 goto out;
 667
 668         rc = -ENOMEM;
 669         oldcon = kzalloc(count + 1, GFP_KERNEL);
 670         if (!oldcon)
 671                 goto out;
 672
 673         newcon = kzalloc(count + 1, GFP_KERNEL);
 674         if (!newcon)
 675                 goto out;
 676
 677         taskcon = kzalloc(count + 1, GFP_KERNEL);
 678         if (!taskcon)
 679                 goto out;
 680
 681         rc = -EINVAL;
 682         if (sscanf(req, "%s %s %hu %s", oldcon, newcon, &tclass, taskcon) != 4)
 683                 goto out;
 684
 685         rc = security_context_str_to_sid(oldcon, &osid, GFP_KERNEL);
 686         if (rc)
 687                 goto out;
 688
 689         rc = security_context_str_to_sid(newcon, &nsid, GFP_KERNEL);
 690         if (rc)
 691                 goto out;
 692
 693         rc = security_context_str_to_sid(taskcon, &tsid, GFP_KERNEL);
 694         if (rc)
 695                 goto out;
 696
 697         rc = security_validate_transition_user(osid, nsid, tsid, tclass);
 698         if (!rc)
 699                 rc = count;
 700 out:
 701         kfree(req);
 702         kfree(oldcon);
 703         kfree(newcon);
 704         kfree(taskcon);
 705         return rc;
 706 }
 707
 708 static const struct file_operations sel_transition_ops = {
 709         .write          = sel_write_validatetrans,
 710         .llseek         = generic_file_llseek,
 711 };
 712
 713 /*
 714  * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
 715  */
 716 static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
 717 static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
 718 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
 719 static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
 720 static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
 721
 722 static ssize_t (*write_op[])(struct file *, char *, size_t) = {
 723         [SEL_ACCESS] = sel_write_access,
 724         [SEL_CREATE] = sel_write_create,
 725         [SEL_RELABEL] = sel_write_relabel,
 726         [SEL_USER] = sel_write_user,
 727         [SEL_MEMBER] = sel_write_member,
 728         [SEL_CONTEXT] = sel_write_context,
 729 };
 730
 731 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
 732 {
 733         ino_t ino = file_inode(file)->i_ino;
 734         char *data;
 735         ssize_t rv;
 736
 737         if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
 738                 return -EINVAL;
 739
 740         data = simple_transaction_get(file, buf, size);
 741         if (IS_ERR(data))
 742                 return PTR_ERR(data);
 743
 744         rv = write_op[ino](file, data, size);
 745         if (rv > 0) {
 746                 simple_transaction_set(file, rv);
 747                 rv = size;
 748         }
 749         return rv;
 750 }
 751
 752 static const struct file_operations transaction_ops = {
 753         .write          = selinux_transaction_write,
 754         .read           = simple_transaction_read,
 755         .release        = simple_transaction_release,
 756         .llseek         = generic_file_llseek,
 757 };
 758
 759 /*
 760  * payload - write methods
 761  * If the method has a response, the response should be put in buf,
 762  * and the length returned.  Otherwise return 0 or and -error.
 763  */
 764
 765 static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
 766 {
 767         char *scon = NULL, *tcon = NULL;
 768         u32 ssid, tsid;
 769         u16 tclass;
 770         struct av_decision avd;
 771         ssize_t length;
 772
 773         length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 774                               SECCLASS_SECURITY, SECURITY__COMPUTE_AV, NULL);
 775         if (length)
 776                 goto out;
 777
 778         length = -ENOMEM;
 779         scon = kzalloc(size + 1, GFP_KERNEL);
 780         if (!scon)
 781                 goto out;
 782
 783         length = -ENOMEM;
 784         tcon = kzalloc(size + 1, GFP_KERNEL);
 785         if (!tcon)
 786                 goto out;
 787
 788         length = -EINVAL;
 789         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 790                 goto out;
 791
 792         length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
 793         if (length)
 794                 goto out;
 795
 796         length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
 797         if (length)
 798                 goto out;
 799
 800         security_compute_av_user(ssid, tsid, tclass, &avd);
 801
 802         length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
 803                           "%x %x %x %x %u %x",
 804                           avd.allowed, 0xffffffff,
 805                           avd.auditallow, avd.auditdeny,
 806                           avd.seqno, avd.flags);
 807 out:
 808         kfree(tcon);
 809         kfree(scon);
 810         return length;
 811 }
 812
 813 static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
 814 {
 815         char *scon = NULL, *tcon = NULL;
 816         char *namebuf = NULL, *objname = NULL;
 817         u32 ssid, tsid, newsid;
 818         u16 tclass;
 819         ssize_t length;
 820         char *newcon = NULL;
 821         u32 len;
 822         int nargs;
 823
 824         length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 825                               SECCLASS_SECURITY, SECURITY__COMPUTE_CREATE,
 826                               NULL);
 827         if (length)
 828                 goto out;
 829
 830         length = -ENOMEM;
 831         scon = kzalloc(size + 1, GFP_KERNEL);
 832         if (!scon)
 833                 goto out;
 834
 835         length = -ENOMEM;
 836         tcon = kzalloc(size + 1, GFP_KERNEL);
 837         if (!tcon)
 838                 goto out;
 839
 840         length = -ENOMEM;
 841         namebuf = kzalloc(size + 1, GFP_KERNEL);
 842         if (!namebuf)
 843                 goto out;
 844
 845         length = -EINVAL;
 846         nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf);
 847         if (nargs < 3 || nargs > 4)
 848                 goto out;
 849         if (nargs == 4) {
 850                 /*
 851                  * If and when the name of new object to be queried contains
 852                  * either whitespace or multibyte characters, they shall be
 853                  * encoded based on the percentage-encoding rule.
 854                  * If not encoded, the sscanf logic picks up only left-half
 855                  * of the supplied name; splitted by a whitespace unexpectedly.
 856                  */
 857                 char   *r, *w;
 858                 int     c1, c2;
 859
 860                 r = w = namebuf;
 861                 do {
 862                         c1 = *r++;
 863                         if (c1 == '+')
 864                                 c1 = ' ';
 865                         else if (c1 == '%') {
 866                                 c1 = hex_to_bin(*r++);
 867                                 if (c1 < 0)
 868                                         goto out;
 869                                 c2 = hex_to_bin(*r++);
 870                                 if (c2 < 0)
 871                                         goto out;
 872                                 c1 = (c1 << 4) | c2;
 873                         }
 874                         *w++ = c1;
 875                 } while (c1 != '\0');
 876
 877                 objname = namebuf;
 878         }
 879
 880         length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
 881         if (length)
 882                 goto out;
 883
 884         length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
 885         if (length)
 886                 goto out;
 887
 888         length = security_transition_sid_user(ssid, tsid, tclass,
 889                                               objname, &newsid);
 890         if (length)
 891                 goto out;
 892
 893         length = security_sid_to_context(newsid, &newcon, &len);
 894         if (length)
 895                 goto out;
 896
 897         length = -ERANGE;
 898         if (len > SIMPLE_TRANSACTION_LIMIT) {
 899                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
 900                         "payload max\n", __func__, len);
 901                 goto out;
 902         }
 903
 904         memcpy(buf, newcon, len);
 905         length = len;
 906 out:
 907         kfree(newcon);
 908         kfree(namebuf);
 909         kfree(tcon);
 910         kfree(scon);
 911         return length;
 912 }
 913
 914 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
 915 {
 916         char *scon = NULL, *tcon = NULL;
 917         u32 ssid, tsid, newsid;
 918         u16 tclass;
 919         ssize_t length;
 920         char *newcon = NULL;
 921         u32 len;
 922
 923         length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 924                               SECCLASS_SECURITY, SECURITY__COMPUTE_RELABEL,
 925                               NULL);
 926         if (length)
 927                 goto out;
 928
 929         length = -ENOMEM;
 930         scon = kzalloc(size + 1, GFP_KERNEL);
 931         if (!scon)
 932                 goto out;
 933
 934         length = -ENOMEM;
 935         tcon = kzalloc(size + 1, GFP_KERNEL);
 936         if (!tcon)
 937                 goto out;
 938
 939         length = -EINVAL;
 940         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 941                 goto out;
 942
 943         length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
 944         if (length)
 945                 goto out;
 946
 947         length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
 948         if (length)
 949                 goto out;
 950
 951         length = security_change_sid(ssid, tsid, tclass, &newsid);
 952         if (length)
 953                 goto out;
 954
 955         length = security_sid_to_context(newsid, &newcon, &len);
 956         if (length)
 957                 goto out;
 958
 959         length = -ERANGE;
 960         if (len > SIMPLE_TRANSACTION_LIMIT)
 961                 goto out;
 962
 963         memcpy(buf, newcon, len);
 964         length = len;
 965 out:
 966         kfree(newcon);
 967         kfree(tcon);
 968         kfree(scon);
 969         return length;
 970 }
 971
 972 static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
 973 {
 974         char *con = NULL, *user = NULL, *ptr;
 975         u32 sid, *sids = NULL;
 976         ssize_t length;
 977         char *newcon;
 978         int i, rc;
 979         u32 len, nsids;
 980
 981         length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 982                               SECCLASS_SECURITY, SECURITY__COMPUTE_USER,
 983                               NULL);
 984         if (length)
 985                 goto out;
 986
 987         length = -ENOMEM;
 988         con = kzalloc(size + 1, GFP_KERNEL);
 989         if (!con)
 990                 goto out;
 991
 992         length = -ENOMEM;
 993         user = kzalloc(size + 1, GFP_KERNEL);
 994         if (!user)
 995                 goto out;
 996
 997         length = -EINVAL;
 998         if (sscanf(buf, "%s %s", con, user) != 2)
 999                 goto out;
1000
1001         length = security_context_str_to_sid(con, &sid, GFP_KERNEL);
1002         if (length)
1003                 goto out;
1004
1005         length = security_get_user_sids(sid, user, &sids, &nsids);
1006         if (length)
1007                 goto out;
1008
1009         length = sprintf(buf, "%u", nsids) + 1;
1010         ptr = buf + length;
1011         for (i = 0; i < nsids; i++) {
1012                 rc = security_sid_to_context(sids[i], &newcon, &len);
1013                 if (rc) {
1014                         length = rc;
1015                         goto out;
1016                 }
1017                 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
1018                         kfree(newcon);
1019                         length = -ERANGE;
1020                         goto out;
1021                 }
1022                 memcpy(ptr, newcon, len);
1023                 kfree(newcon);
1024                 ptr += len;
1025                 length += len;
1026         }
1027 out:
1028         kfree(sids);
1029         kfree(user);
1030         kfree(con);
1031         return length;
1032 }
1033
1034 static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
1035 {
1036         char *scon = NULL, *tcon = NULL;
1037         u32 ssid, tsid, newsid;
1038         u16 tclass;
1039         ssize_t length;
1040         char *newcon = NULL;
1041         u32 len;
1042
1043         length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1044                               SECCLASS_SECURITY, SECURITY__COMPUTE_MEMBER,
1045                               NULL);
1046         if (length)
1047                 goto out;
1048
1049         length = -ENOMEM;
1050         scon = kzalloc(size + 1, GFP_KERNEL);
1051         if (!scon)
1052                 goto out;
1053
1054         length = -ENOMEM;
1055         tcon = kzalloc(size + 1, GFP_KERNEL);
1056         if (!tcon)
1057                 goto out;
1058
1059         length = -EINVAL;
1060         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
1061                 goto out;
1062
1063         length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
1064         if (length)
1065                 goto out;
1066
1067         length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
1068         if (length)
1069                 goto out;
1070
1071         length = security_member_sid(ssid, tsid, tclass, &newsid);
1072         if (length)
1073                 goto out;
1074
1075         length = security_sid_to_context(newsid, &newcon, &len);
1076         if (length)
1077                 goto out;
1078
1079         length = -ERANGE;
1080         if (len > SIMPLE_TRANSACTION_LIMIT) {
1081                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
1082                         "payload max\n", __func__, len);
1083                 goto out;
1084         }
1085
1086         memcpy(buf, newcon, len);
1087         length = len;
1088 out:
1089         kfree(newcon);
1090         kfree(tcon);
1091         kfree(scon);
1092         return length;
1093 }
1094
1095 static struct inode *sel_make_inode(struct super_block *sb, int mode)
1096 {
1097         struct inode *ret = new_inode(sb);
1098
1099         if (ret) {
1100                 ret->i_mode = mode;
1101                 ret->i_atime = ret->i_mtime = ret->i_ctime = current_time(ret);
1102         }
1103         return ret;
1104 }
1105
1106 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
1107                              size_t count, loff_t *ppos)
1108 {
1109         char *page = NULL;
1110         ssize_t length;
1111         ssize_t ret;
1112         int cur_enforcing;
1113         unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
1114         const char *name = filep->f_path.dentry->d_name.name;
1115
1116         mutex_lock(&sel_mutex);
1117
1118         ret = -EINVAL;
1119         if (index >= bool_num || strcmp(name, bool_pending_names[index]))
1120                 goto out;
1121
1122         ret = -ENOMEM;
1123         page = (char *)get_zeroed_page(GFP_KERNEL);
1124         if (!page)
1125                 goto out;
1126
1127         cur_enforcing = security_get_bool_value(index);
1128         if (cur_enforcing < 0) {
1129                 ret = cur_enforcing;
1130                 goto out;
1131         }
1132         length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
1133                           bool_pending_values[index]);
1134         ret = simple_read_from_buffer(buf, count, ppos, page, length);
1135 out:
1136         mutex_unlock(&sel_mutex);
1137         free_page((unsigned long)page);
1138         return ret;
1139 }
1140
1141 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
1142                               size_t count, loff_t *ppos)
1143 {
1144         char *page = NULL;
1145         ssize_t length;
1146         int new_value;
1147         unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
1148         const char *name = filep->f_path.dentry->d_name.name;
1149
1150         mutex_lock(&sel_mutex);
1151
1152         length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1153                               SECCLASS_SECURITY, SECURITY__SETBOOL,
1154                               NULL);
1155         if (length)
1156                 goto out;
1157
1158         length = -EINVAL;
1159         if (index >= bool_num || strcmp(name, bool_pending_names[index]))
1160                 goto out;
1161
1162         length = -ENOMEM;
1163         if (count >= PAGE_SIZE)
1164                 goto out;
1165
1166         /* No partial writes. */
1167         length = -EINVAL;
1168         if (*ppos != 0)
1169                 goto out;
1170
1171         page = memdup_user_nul(buf, count);
1172         if (IS_ERR(page)) {
1173                 length = PTR_ERR(page);
1174                 page = NULL;
1175                 goto out;
1176         }
1177
1178         length = -EINVAL;
1179         if (sscanf(page, "%d", &new_value) != 1)
1180                 goto out;
1181
1182         if (new_value)
1183                 new_value = 1;
1184
1185         bool_pending_values[index] = new_value;
1186         length = count;
1187
1188 out:
1189         mutex_unlock(&sel_mutex);
1190         kfree(page);
1191         return length;
1192 }
1193
1194 static const struct file_operations sel_bool_ops = {
1195         .read           = sel_read_bool,
1196         .write          = sel_write_bool,
1197         .llseek         = generic_file_llseek,
1198 };
1199
1200 static ssize_t sel_commit_bools_write(struct file *filep,
1201                                       const char __user *buf,
1202                                       size_t count, loff_t *ppos)
1203 {
1204         char *page = NULL;
1205         ssize_t length;
1206         int new_value;
1207
1208         mutex_lock(&sel_mutex);
1209
1210         length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1211                               SECCLASS_SECURITY, SECURITY__SETBOOL,
1212                               NULL);
1213         if (length)
1214                 goto out;
1215
1216         length = -ENOMEM;
1217         if (count >= PAGE_SIZE)
1218                 goto out;
1219
1220         /* No partial writes. */
1221         length = -EINVAL;
1222         if (*ppos != 0)
1223                 goto out;
1224
1225         page = memdup_user_nul(buf, count);
1226         if (IS_ERR(page)) {
1227                 length = PTR_ERR(page);
1228                 page = NULL;
1229                 goto out;
1230         }
1231
1232         length = -EINVAL;
1233         if (sscanf(page, "%d", &new_value) != 1)
1234                 goto out;
1235
1236         length = 0;
1237         if (new_value && bool_pending_values)
1238                 length = security_set_bools(bool_num, bool_pending_values);
1239
1240         if (!length)
1241                 length = count;
1242
1243 out:
1244         mutex_unlock(&sel_mutex);
1245         kfree(page);
1246         return length;
1247 }
1248
1249 static const struct file_operations sel_commit_bools_ops = {
1250         .write          = sel_commit_bools_write,
1251         .llseek         = generic_file_llseek,
1252 };
1253
1254 static void sel_remove_entries(struct dentry *de)
1255 {
1256         d_genocide(de);
1257         shrink_dcache_parent(de);
1258 }
1259
1260 #define BOOL_DIR_NAME "booleans"
1261
1262 static int sel_make_bools(void)
1263 {
1264         int i, ret;
1265         ssize_t len;
1266         struct dentry *dentry = NULL;
1267         struct dentry *dir = bool_dir;
1268         struct inode *inode = NULL;
1269         struct inode_security_struct *isec;
1270         char **names = NULL, *page;
1271         int num;
1272         int *values = NULL;
1273         u32 sid;
1274
1275         /* remove any existing files */
1276         for (i = 0; i < bool_num; i++)
1277                 kfree(bool_pending_names[i]);
1278         kfree(bool_pending_names);
1279         kfree(bool_pending_values);
1280         bool_num = 0;
1281         bool_pending_names = NULL;
1282         bool_pending_values = NULL;
1283
1284         sel_remove_entries(dir);
1285
1286         ret = -ENOMEM;
1287         page = (char *)get_zeroed_page(GFP_KERNEL);
1288         if (!page)
1289                 goto out;
1290
1291         ret = security_get_bools(&num, &names, &values);
1292         if (ret)
1293                 goto out;
1294
1295         for (i = 0; i < num; i++) {
1296                 ret = -ENOMEM;
1297                 dentry = d_alloc_name(dir, names[i]);
1298                 if (!dentry)
1299                         goto out;
1300
1301                 ret = -ENOMEM;
1302                 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1303                 if (!inode)
1304                         goto out;
1305
1306                 ret = -ENAMETOOLONG;
1307                 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1308                 if (len >= PAGE_SIZE)
1309                         goto out;
1310
1311                 isec = (struct inode_security_struct *)inode->i_security;
1312                 ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid);
1313                 if (ret) {
1314                         pr_warn_ratelimited("SELinux: no sid found, defaulting to security isid for %s\n",
1315                                            page);
1316                         sid = SECINITSID_SECURITY;
1317                 }
1318
1319                 isec->sid = sid;
1320                 isec->initialized = LABEL_INITIALIZED;
1321                 inode->i_fop = &sel_bool_ops;
1322                 inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1323                 d_add(dentry, inode);
1324         }
1325         bool_num = num;
1326         bool_pending_names = names;
1327         bool_pending_values = values;
1328
1329         free_page((unsigned long)page);
1330         return 0;
1331 out:
1332         free_page((unsigned long)page);
1333
1334         if (names) {
1335                 for (i = 0; i < num; i++)
1336                         kfree(names[i]);
1337                 kfree(names);
1338         }
1339         kfree(values);
1340         sel_remove_entries(dir);
1341
1342         return ret;
1343 }
1344
1345 #define NULL_FILE_NAME "null"
1346
1347 struct path selinux_null;
1348
1349 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1350                                             size_t count, loff_t *ppos)
1351 {
1352         char tmpbuf[TMPBUFLEN];
1353         ssize_t length;
1354
1355         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
1356         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1357 }
1358
1359 static ssize_t sel_write_avc_cache_threshold(struct file *file,
1360                                              const char __user *buf,
1361                                              size_t count, loff_t *ppos)
1362
1363 {
1364         char *page;
1365         ssize_t ret;
1366         unsigned int new_value;
1367
1368         ret = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1369                            SECCLASS_SECURITY, SECURITY__SETSECPARAM,
1370                            NULL);
1371         if (ret)
1372                 return ret;
1373
1374         if (count >= PAGE_SIZE)
1375                 return -ENOMEM;
1376
1377         /* No partial writes. */
1378         if (*ppos != 0)
1379                 return -EINVAL;
1380
1381         page = memdup_user_nul(buf, count);
1382         if (IS_ERR(page))
1383                 return PTR_ERR(page);
1384
1385         ret = -EINVAL;
1386         if (sscanf(page, "%u", &new_value) != 1)
1387                 goto out;
1388
1389         avc_cache_threshold = new_value;
1390
1391         ret = count;
1392 out:
1393         kfree(page);
1394         return ret;
1395 }
1396
1397 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1398                                        size_t count, loff_t *ppos)
1399 {
1400         char *page;
1401         ssize_t length;
1402
1403         page = (char *)__get_free_page(GFP_KERNEL);
1404         if (!page)
1405                 return -ENOMEM;
1406
1407         length = avc_get_hash_stats(page);
1408         if (length >= 0)
1409                 length = simple_read_from_buffer(buf, count, ppos, page, length);
1410         free_page((unsigned long)page);
1411
1412         return length;
1413 }
1414
1415 static const struct file_operations sel_avc_cache_threshold_ops = {
1416         .read           = sel_read_avc_cache_threshold,
1417         .write          = sel_write_avc_cache_threshold,
1418         .llseek         = generic_file_llseek,
1419 };
1420
1421 static const struct file_operations sel_avc_hash_stats_ops = {
1422         .read           = sel_read_avc_hash_stats,
1423         .llseek         = generic_file_llseek,
1424 };
1425
1426 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1427 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1428 {
1429         int cpu;
1430
1431         for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
1432                 if (!cpu_possible(cpu))
1433                         continue;
1434                 *idx = cpu + 1;
1435                 return &per_cpu(avc_cache_stats, cpu);
1436         }
1437         return NULL;
1438 }
1439
1440 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1441 {
1442         loff_t n = *pos - 1;
1443
1444         if (*pos == 0)
1445                 return SEQ_START_TOKEN;
1446
1447         return sel_avc_get_stat_idx(&n);
1448 }
1449
1450 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1451 {
1452         return sel_avc_get_stat_idx(pos);
1453 }
1454
1455 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1456 {
1457         struct avc_cache_stats *st = v;
1458
1459         if (v == SEQ_START_TOKEN)
1460                 seq_printf(seq, "lookups hits misses allocations reclaims "
1461                            "frees\n");
1462         else {
1463                 unsigned int lookups = st->lookups;
1464                 unsigned int misses = st->misses;
1465                 unsigned int hits = lookups - misses;
1466                 seq_printf(seq, "%u %u %u %u %u %u\n", lookups,
1467                            hits, misses, st->allocations,
1468                            st->reclaims, st->frees);
1469         }
1470         return 0;
1471 }
1472
1473 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1474 { }
1475
1476 static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1477         .start          = sel_avc_stats_seq_start,
1478         .next           = sel_avc_stats_seq_next,
1479         .show           = sel_avc_stats_seq_show,
1480         .stop           = sel_avc_stats_seq_stop,
1481 };
1482
1483 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1484 {
1485         return seq_open(file, &sel_avc_cache_stats_seq_ops);
1486 }
1487
1488 static const struct file_operations sel_avc_cache_stats_ops = {
1489         .open           = sel_open_avc_cache_stats,
1490         .read           = seq_read,
1491         .llseek         = seq_lseek,
1492         .release        = seq_release,
1493 };
1494 #endif
1495
1496 static int sel_make_avc_files(struct dentry *dir)
1497 {
1498         int i;
1499         static struct tree_descr files[] = {
1500                 { "cache_threshold",
1501                   &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1502                 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1503 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1504                 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1505 #endif
1506         };
1507
1508         for (i = 0; i < ARRAY_SIZE(files); i++) {
1509                 struct inode *inode;
1510                 struct dentry *dentry;
1511
1512                 dentry = d_alloc_name(dir, files[i].name);
1513                 if (!dentry)
1514                         return -ENOMEM;
1515
1516                 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1517                 if (!inode)
1518                         return -ENOMEM;
1519
1520                 inode->i_fop = files[i].ops;
1521                 inode->i_ino = ++sel_last_ino;
1522                 d_add(dentry, inode);
1523         }
1524
1525         return 0;
1526 }
1527
1528 static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1529                                 size_t count, loff_t *ppos)
1530 {
1531         char *con;
1532         u32 sid, len;
1533         ssize_t ret;
1534
1535         sid = file_inode(file)->i_ino&SEL_INO_MASK;
1536         ret = security_sid_to_context(sid, &con, &len);
1537         if (ret)
1538                 return ret;
1539
1540         ret = simple_read_from_buffer(buf, count, ppos, con, len);
1541         kfree(con);
1542         return ret;
1543 }
1544
1545 static const struct file_operations sel_initcon_ops = {
1546         .read           = sel_read_initcon,
1547         .llseek         = generic_file_llseek,
1548 };
1549
1550 static int sel_make_initcon_files(struct dentry *dir)
1551 {
1552         int i;
1553
1554         for (i = 1; i <= SECINITSID_NUM; i++) {
1555                 struct inode *inode;
1556                 struct dentry *dentry;
1557                 dentry = d_alloc_name(dir, security_get_initial_sid_context(i));
1558                 if (!dentry)
1559                         return -ENOMEM;
1560
1561                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1562                 if (!inode)
1563                         return -ENOMEM;
1564
1565                 inode->i_fop = &sel_initcon_ops;
1566                 inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1567                 d_add(dentry, inode);
1568         }
1569
1570         return 0;
1571 }
1572
1573 static inline unsigned long sel_class_to_ino(u16 class)
1574 {
1575         return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1576 }
1577
1578 static inline u16 sel_ino_to_class(unsigned long ino)
1579 {
1580         return (ino & SEL_INO_MASK) / (SEL_VEC_MAX + 1);
1581 }
1582
1583 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1584 {
1585         return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1586 }
1587
1588 static inline u32 sel_ino_to_perm(unsigned long ino)
1589 {
1590         return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1591 }
1592
1593 static ssize_t sel_read_class(struct file *file, char __user *buf,
1594                                 size_t count, loff_t *ppos)
1595 {
1596         unsigned long ino = file_inode(file)->i_ino;
1597         char res[TMPBUFLEN];
1598         ssize_t len = snprintf(res, sizeof(res), "%d", sel_ino_to_class(ino));
1599         return simple_read_from_buffer(buf, count, ppos, res, len);
1600 }
1601
1602 static const struct file_operations sel_class_ops = {
1603         .read           = sel_read_class,
1604         .llseek         = generic_file_llseek,
1605 };
1606
1607 static ssize_t sel_read_perm(struct file *file, char __user *buf,
1608                                 size_t count, loff_t *ppos)
1609 {
1610         unsigned long ino = file_inode(file)->i_ino;
1611         char res[TMPBUFLEN];
1612         ssize_t len = snprintf(res, sizeof(res), "%d", sel_ino_to_perm(ino));
1613         return simple_read_from_buffer(buf, count, ppos, res, len);
1614 }
1615
1616 static const struct file_operations sel_perm_ops = {
1617         .read           = sel_read_perm,
1618         .llseek         = generic_file_llseek,
1619 };
1620
1621 static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1622                                   size_t count, loff_t *ppos)
1623 {
1624         int value;
1625         char tmpbuf[TMPBUFLEN];
1626         ssize_t length;
1627         unsigned long i_ino = file_inode(file)->i_ino;
1628
1629         value = security_policycap_supported(i_ino & SEL_INO_MASK);
1630         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
1631
1632         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1633 }
1634
1635 static const struct file_operations sel_policycap_ops = {
1636         .read           = sel_read_policycap,
1637         .llseek         = generic_file_llseek,
1638 };
1639
1640 static int sel_make_perm_files(char *objclass, int classvalue,
1641                                 struct dentry *dir)
1642 {
1643         int i, rc, nperms;
1644         char **perms;
1645
1646         rc = security_get_permissions(objclass, &perms, &nperms);
1647         if (rc)
1648                 return rc;
1649
1650         for (i = 0; i < nperms; i++) {
1651                 struct inode *inode;
1652                 struct dentry *dentry;
1653
1654                 rc = -ENOMEM;
1655                 dentry = d_alloc_name(dir, perms[i]);
1656                 if (!dentry)
1657                         goto out;
1658
1659                 rc = -ENOMEM;
1660                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1661                 if (!inode)
1662                         goto out;
1663
1664                 inode->i_fop = &sel_perm_ops;
1665                 /* i+1 since perm values are 1-indexed */
1666                 inode->i_ino = sel_perm_to_ino(classvalue, i + 1);
1667                 d_add(dentry, inode);
1668         }
1669         rc = 0;
1670 out:
1671         for (i = 0; i < nperms; i++)
1672                 kfree(perms[i]);
1673         kfree(perms);
1674         return rc;
1675 }
1676
1677 static int sel_make_class_dir_entries(char *classname, int index,
1678                                         struct dentry *dir)
1679 {
1680         struct dentry *dentry = NULL;
1681         struct inode *inode = NULL;
1682         int rc;
1683
1684         dentry = d_alloc_name(dir, "index");
1685         if (!dentry)
1686                 return -ENOMEM;
1687
1688         inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1689         if (!inode)
1690                 return -ENOMEM;
1691
1692         inode->i_fop = &sel_class_ops;
1693         inode->i_ino = sel_class_to_ino(index);
1694         d_add(dentry, inode);
1695
1696         dentry = sel_make_dir(dir, "perms", &last_class_ino);
1697         if (IS_ERR(dentry))
1698                 return PTR_ERR(dentry);
1699
1700         rc = sel_make_perm_files(classname, index, dentry);
1701
1702         return rc;
1703 }
1704
1705 static int sel_make_classes(void)
1706 {
1707         int rc, nclasses, i;
1708         char **classes;
1709
1710         /* delete any existing entries */
1711         sel_remove_entries(class_dir);
1712
1713         rc = security_get_classes(&classes, &nclasses);
1714         if (rc)
1715                 return rc;
1716
1717         /* +2 since classes are 1-indexed */
1718         last_class_ino = sel_class_to_ino(nclasses + 2);
1719
1720         for (i = 0; i < nclasses; i++) {
1721                 struct dentry *class_name_dir;
1722
1723                 class_name_dir = sel_make_dir(class_dir, classes[i],
1724                                 &last_class_ino);
1725                 if (IS_ERR(class_name_dir)) {
1726                         rc = PTR_ERR(class_name_dir);
1727                         goto out;
1728                 }
1729
1730                 /* i+1 since class values are 1-indexed */
1731                 rc = sel_make_class_dir_entries(classes[i], i + 1,
1732                                 class_name_dir);
1733                 if (rc)
1734                         goto out;
1735         }
1736         rc = 0;
1737 out:
1738         for (i = 0; i < nclasses; i++)
1739                 kfree(classes[i]);
1740         kfree(classes);
1741         return rc;
1742 }
1743
1744 static int sel_make_policycap(void)
1745 {
1746         unsigned int iter;
1747         struct dentry *dentry = NULL;
1748         struct inode *inode = NULL;
1749
1750         sel_remove_entries(policycap_dir);
1751
1752         for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) {
1753                 if (iter < ARRAY_SIZE(policycap_names))
1754                         dentry = d_alloc_name(policycap_dir,
1755                                               policycap_names[iter]);
1756                 else
1757                         dentry = d_alloc_name(policycap_dir, "unknown");
1758
1759                 if (dentry == NULL)
1760                         return -ENOMEM;
1761
1762                 inode = sel_make_inode(policycap_dir->d_sb, S_IFREG | S_IRUGO);
1763                 if (inode == NULL)
1764                         return -ENOMEM;
1765
1766                 inode->i_fop = &sel_policycap_ops;
1767                 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
1768                 d_add(dentry, inode);
1769         }
1770
1771         return 0;
1772 }
1773
1774 static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
1775                         unsigned long *ino)
1776 {
1777         struct dentry *dentry = d_alloc_name(dir, name);
1778         struct inode *inode;
1779
1780         if (!dentry)
1781                 return ERR_PTR(-ENOMEM);
1782
1783         inode = sel_make_inode(dir->d_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1784         if (!inode) {
1785                 dput(dentry);
1786                 return ERR_PTR(-ENOMEM);
1787         }
1788
1789         inode->i_op = &simple_dir_inode_operations;
1790         inode->i_fop = &simple_dir_operations;
1791         inode->i_ino = ++(*ino);
1792         /* directory inodes start off with i_nlink == 2 (for "." entry) */
1793         inc_nlink(inode);
1794         d_add(dentry, inode);
1795         /* bump link count on parent directory, too */
1796         inc_nlink(d_inode(dir));
1797
1798         return dentry;
1799 }
1800
1801 static int sel_fill_super(struct super_block *sb, void *data, int silent)
1802 {
1803         int ret;
1804         struct dentry *dentry;
1805         struct inode *inode;
1806         struct inode_security_struct *isec;
1807
1808         static struct tree_descr selinux_files[] = {
1809                 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1810                 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1811                 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1812                 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1813                 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1814                 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1815                 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1816                 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1817                 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1818                 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1819                 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1820                 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1821                 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1822                 [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
1823                 [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
1824                 [SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO},
1825                 [SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUGO},
1826                 [SEL_VALIDATE_TRANS] = {"validatetrans", &sel_transition_ops,
1827                                         S_IWUGO},
1828                 /* last one */ {""}
1829         };
1830         ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1831         if (ret)
1832                 goto err;
1833
1834         bool_dir = sel_make_dir(sb->s_root, BOOL_DIR_NAME, &sel_last_ino);
1835         if (IS_ERR(bool_dir)) {
1836                 ret = PTR_ERR(bool_dir);
1837                 bool_dir = NULL;
1838                 goto err;
1839         }
1840
1841         ret = -ENOMEM;
1842         dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1843         if (!dentry)
1844                 goto err;
1845
1846         ret = -ENOMEM;
1847         inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1848         if (!inode)
1849                 goto err;
1850
1851         inode->i_ino = ++sel_last_ino;
1852         isec = (struct inode_security_struct *)inode->i_security;
1853         isec->sid = SECINITSID_DEVNULL;
1854         isec->sclass = SECCLASS_CHR_FILE;
1855         isec->initialized = LABEL_INITIALIZED;
1856
1857         init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1858         d_add(dentry, inode);
1859         selinux_null.dentry = dentry;
1860
1861         dentry = sel_make_dir(sb->s_root, "avc", &sel_last_ino);
1862         if (IS_ERR(dentry)) {
1863                 ret = PTR_ERR(dentry);
1864                 goto err;
1865         }
1866
1867         ret = sel_make_avc_files(dentry);
1868         if (ret)
1869                 goto err;
1870
1871         dentry = sel_make_dir(sb->s_root, "initial_contexts", &sel_last_ino);
1872         if (IS_ERR(dentry)) {
1873                 ret = PTR_ERR(dentry);
1874                 goto err;
1875         }
1876
1877         ret = sel_make_initcon_files(dentry);
1878         if (ret)
1879                 goto err;
1880
1881         class_dir = sel_make_dir(sb->s_root, "class", &sel_last_ino);
1882         if (IS_ERR(class_dir)) {
1883                 ret = PTR_ERR(class_dir);
1884                 class_dir = NULL;
1885                 goto err;
1886         }
1887
1888         policycap_dir = sel_make_dir(sb->s_root, "policy_capabilities", &sel_last_ino);
1889         if (IS_ERR(policycap_dir)) {
1890                 ret = PTR_ERR(policycap_dir);
1891                 policycap_dir = NULL;
1892                 goto err;
1893         }
1894         return 0;
1895 err:
1896         printk(KERN_ERR "SELinux: %s:  failed while creating inodes\n",
1897                 __func__);
1898         return ret;
1899 }
1900
1901 static struct dentry *sel_mount(struct file_system_type *fs_type,
1902                       int flags, const char *dev_name, void *data)
1903 {
1904         return mount_single(fs_type, flags, data, sel_fill_super);
1905 }
1906
1907 static struct file_system_type sel_fs_type = {
1908         .name           = "selinuxfs",
1909         .mount          = sel_mount,
1910         .kill_sb        = kill_litter_super,
1911 };
1912
1913 struct vfsmount *selinuxfs_mount;
1914
1915 static int __init init_sel_fs(void)
1916 {
1917         int err;
1918
1919         if (!selinux_enabled)
1920                 return 0;
1921
1922         err = sysfs_create_mount_point(fs_kobj, "selinux");
1923         if (err)
1924                 return err;
1925
1926         err = register_filesystem(&sel_fs_type);
1927         if (err) {
1928                 sysfs_remove_mount_point(fs_kobj, "selinux");
1929                 return err;
1930         }
1931
1932         selinux_null.mnt = selinuxfs_mount = kern_mount(&sel_fs_type);
1933         if (IS_ERR(selinuxfs_mount)) {
1934                 printk(KERN_ERR "selinuxfs:  could not mount!\n");
1935                 err = PTR_ERR(selinuxfs_mount);
1936                 selinuxfs_mount = NULL;
1937         }
1938
1939         return err;
1940 }
1941
1942 __initcall(init_sel_fs);
1943
1944 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
1945 void exit_sel_fs(void)
1946 {
1947         sysfs_remove_mount_point(fs_kobj, "selinux");
1948         kern_unmount(selinuxfs_mount);
1949         unregister_filesystem(&sel_fs_type);
1950 }
1951 #endif