security/selinux/selinuxfs.c

   1 /* Updated: Karl MacMillan <kmacmillan@tresys.com>
   2  *
   3  *      Added conditional policy language extensions
   4  *
   5  *  Updated: Hewlett-Packard <paul.moore@hp.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
  32 /* selinuxfs pseudo filesystem for exporting the security policy API.
  33    Based on the proc code and the fs/nfsd/nfsctl.c code. */
  34
  35 #include "flask.h"
  36 #include "avc.h"
  37 #include "avc_ss.h"
  38 #include "security.h"
  39 #include "objsec.h"
  40 #include "conditional.h"
  41
  42 /* Policy capability filenames */
  43 static char *policycap_names[] = {
  44         "network_peer_controls",
  45         "open_perms"
  46 };
  47
  48 unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
  49
  50 #ifdef CONFIG_SECURITY_SELINUX_ENABLE_SECMARK_DEFAULT
  51 #define SELINUX_COMPAT_NET_VALUE 0
  52 #else
  53 #define SELINUX_COMPAT_NET_VALUE 1
  54 #endif
  55
  56 int selinux_compat_net = SELINUX_COMPAT_NET_VALUE;
  57
  58 static int __init checkreqprot_setup(char *str)
  59 {
  60         unsigned long checkreqprot;
  61         if (!strict_strtoul(str, 0, &checkreqprot))
  62                 selinux_checkreqprot = checkreqprot ? 1 : 0;
  63         return 1;
  64 }
  65 __setup("checkreqprot=", checkreqprot_setup);
  66
  67 static int __init selinux_compat_net_setup(char *str)
  68 {
  69         unsigned long compat_net;
  70         if (!strict_strtoul(str, 0, &compat_net))
  71                 selinux_compat_net = compat_net ? 1 : 0;
  72         return 1;
  73 }
  74 __setup("selinux_compat_net=", selinux_compat_net_setup);
  75
  76
  77 static DEFINE_MUTEX(sel_mutex);
  78
  79 /* global data for booleans */
  80 static struct dentry *bool_dir;
  81 static int bool_num;
  82 static char **bool_pending_names;
  83 static int *bool_pending_values;
  84
  85 /* global data for classes */
  86 static struct dentry *class_dir;
  87 static unsigned long last_class_ino;
  88
  89 /* global data for policy capabilities */
  90 static struct dentry *policycap_dir;
  91
  92 extern void selnl_notify_setenforce(int val);
  93
  94 /* Check whether a task is allowed to use a security operation. */
  95 static int task_has_security(struct task_struct *tsk,
  96                              u32 perms)
  97 {
  98         struct task_security_struct *tsec;
  99
 100         tsec = tsk->security;
 101         if (!tsec)
 102                 return -EACCES;
 103
 104         return avc_has_perm(tsec->sid, SECINITSID_SECURITY,
 105                             SECCLASS_SECURITY, perms, NULL);
 106 }
 107
 108 enum sel_inos {
 109         SEL_ROOT_INO = 2,
 110         SEL_LOAD,       /* load policy */
 111         SEL_ENFORCE,    /* get or set enforcing status */
 112         SEL_CONTEXT,    /* validate context */
 113         SEL_ACCESS,     /* compute access decision */
 114         SEL_CREATE,     /* compute create labeling decision */
 115         SEL_RELABEL,    /* compute relabeling decision */
 116         SEL_USER,       /* compute reachable user contexts */
 117         SEL_POLICYVERS, /* return policy version for this kernel */
 118         SEL_COMMIT_BOOLS, /* commit new boolean values */
 119         SEL_MLS,        /* return if MLS policy is enabled */
 120         SEL_DISABLE,    /* disable SELinux until next reboot */
 121         SEL_MEMBER,     /* compute polyinstantiation membership decision */
 122         SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
 123         SEL_COMPAT_NET, /* whether to use old compat network packet controls */
 124         SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */
 125         SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */
 126         SEL_INO_NEXT,   /* The next inode number to use */
 127 };
 128
 129 static unsigned long sel_last_ino = SEL_INO_NEXT - 1;
 130
 131 #define SEL_INITCON_INO_OFFSET          0x01000000
 132 #define SEL_BOOL_INO_OFFSET             0x02000000
 133 #define SEL_CLASS_INO_OFFSET            0x04000000
 134 #define SEL_POLICYCAP_INO_OFFSET        0x08000000
 135 #define SEL_INO_MASK                    0x00ffffff
 136
 137 #define TMPBUFLEN       12
 138 static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
 139                                 size_t count, loff_t *ppos)
 140 {
 141         char tmpbuf[TMPBUFLEN];
 142         ssize_t length;
 143
 144         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing);
 145         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 146 }
 147
 148 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 149 static ssize_t sel_write_enforce(struct file *file, const char __user *buf,
 150                                  size_t count, loff_t *ppos)
 151
 152 {
 153         char *page;
 154         ssize_t length;
 155         int new_value;
 156
 157         if (count >= PAGE_SIZE)
 158                 return -ENOMEM;
 159         if (*ppos != 0) {
 160                 /* No partial writes. */
 161                 return -EINVAL;
 162         }
 163         page = (char *)get_zeroed_page(GFP_KERNEL);
 164         if (!page)
 165                 return -ENOMEM;
 166         length = -EFAULT;
 167         if (copy_from_user(page, buf, count))
 168                 goto out;
 169
 170         length = -EINVAL;
 171         if (sscanf(page, "%d", &new_value) != 1)
 172                 goto out;
 173
 174         if (new_value != selinux_enforcing) {
 175                 length = task_has_security(current, SECURITY__SETENFORCE);
 176                 if (length)
 177                         goto out;
 178                 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
 179                         "enforcing=%d old_enforcing=%d auid=%u ses=%u",
 180                         new_value, selinux_enforcing,
 181                         audit_get_loginuid(current),
 182                         audit_get_sessionid(current));
 183                 selinux_enforcing = new_value;
 184                 if (selinux_enforcing)
 185                         avc_ss_reset(0);
 186                 selnl_notify_setenforce(selinux_enforcing);
 187         }
 188         length = count;
 189 out:
 190         free_page((unsigned long) page);
 191         return length;
 192 }
 193 #else
 194 #define sel_write_enforce NULL
 195 #endif
 196
 197 static const struct file_operations sel_enforce_ops = {
 198         .read           = sel_read_enforce,
 199         .write          = sel_write_enforce,
 200 };
 201
 202 static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
 203                                         size_t count, loff_t *ppos)
 204 {
 205         char tmpbuf[TMPBUFLEN];
 206         ssize_t length;
 207         ino_t ino = filp->f_path.dentry->d_inode->i_ino;
 208         int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ?
 209                 security_get_reject_unknown() : !security_get_allow_unknown();
 210
 211         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown);
 212         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 213 }
 214
 215 static const struct file_operations sel_handle_unknown_ops = {
 216         .read           = sel_read_handle_unknown,
 217 };
 218
 219 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
 220 static ssize_t sel_write_disable(struct file *file, const char __user *buf,
 221                                  size_t count, loff_t *ppos)
 222
 223 {
 224         char *page;
 225         ssize_t length;
 226         int new_value;
 227         extern int selinux_disable(void);
 228
 229         if (count >= PAGE_SIZE)
 230                 return -ENOMEM;
 231         if (*ppos != 0) {
 232                 /* No partial writes. */
 233                 return -EINVAL;
 234         }
 235         page = (char *)get_zeroed_page(GFP_KERNEL);
 236         if (!page)
 237                 return -ENOMEM;
 238         length = -EFAULT;
 239         if (copy_from_user(page, buf, count))
 240                 goto out;
 241
 242         length = -EINVAL;
 243         if (sscanf(page, "%d", &new_value) != 1)
 244                 goto out;
 245
 246         if (new_value) {
 247                 length = selinux_disable();
 248                 if (length < 0)
 249                         goto out;
 250                 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
 251                         "selinux=0 auid=%u ses=%u",
 252                         audit_get_loginuid(current),
 253                         audit_get_sessionid(current));
 254         }
 255
 256         length = count;
 257 out:
 258         free_page((unsigned long) page);
 259         return length;
 260 }
 261 #else
 262 #define sel_write_disable NULL
 263 #endif
 264
 265 static const struct file_operations sel_disable_ops = {
 266         .write          = sel_write_disable,
 267 };
 268
 269 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
 270                                    size_t count, loff_t *ppos)
 271 {
 272         char tmpbuf[TMPBUFLEN];
 273         ssize_t length;
 274
 275         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
 276         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 277 }
 278
 279 static const struct file_operations sel_policyvers_ops = {
 280         .read           = sel_read_policyvers,
 281 };
 282
 283 /* declaration for sel_write_load */
 284 static int sel_make_bools(void);
 285 static int sel_make_classes(void);
 286 static int sel_make_policycap(void);
 287
 288 /* declaration for sel_make_class_dirs */
 289 static int sel_make_dir(struct inode *dir, struct dentry *dentry,
 290                         unsigned long *ino);
 291
 292 static ssize_t sel_read_mls(struct file *filp, char __user *buf,
 293                                 size_t count, loff_t *ppos)
 294 {
 295         char tmpbuf[TMPBUFLEN];
 296         ssize_t length;
 297
 298         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_mls_enabled);
 299         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 300 }
 301
 302 static const struct file_operations sel_mls_ops = {
 303         .read           = sel_read_mls,
 304 };
 305
 306 static ssize_t sel_write_load(struct file *file, const char __user *buf,
 307                               size_t count, loff_t *ppos)
 308
 309 {
 310         int ret;
 311         ssize_t length;
 312         void *data = NULL;
 313
 314         mutex_lock(&sel_mutex);
 315
 316         length = task_has_security(current, SECURITY__LOAD_POLICY);
 317         if (length)
 318                 goto out;
 319
 320         if (*ppos != 0) {
 321                 /* No partial writes. */
 322                 length = -EINVAL;
 323                 goto out;
 324         }
 325
 326         if ((count > 64 * 1024 * 1024)
 327             || (data = vmalloc(count)) == NULL) {
 328                 length = -ENOMEM;
 329                 goto out;
 330         }
 331
 332         length = -EFAULT;
 333         if (copy_from_user(data, buf, count) != 0)
 334                 goto out;
 335
 336         length = security_load_policy(data, count);
 337         if (length)
 338                 goto out;
 339
 340         ret = sel_make_bools();
 341         if (ret) {
 342                 length = ret;
 343                 goto out1;
 344         }
 345
 346         ret = sel_make_classes();
 347         if (ret) {
 348                 length = ret;
 349                 goto out1;
 350         }
 351
 352         ret = sel_make_policycap();
 353         if (ret)
 354                 length = ret;
 355         else
 356                 length = count;
 357
 358 out1:
 359         audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
 360                 "policy loaded auid=%u ses=%u",
 361                 audit_get_loginuid(current),
 362                 audit_get_sessionid(current));
 363 out:
 364         mutex_unlock(&sel_mutex);
 365         vfree(data);
 366         return length;
 367 }
 368
 369 static const struct file_operations sel_load_ops = {
 370         .write          = sel_write_load,
 371 };
 372
 373 static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
 374 {
 375         char *canon;
 376         u32 sid, len;
 377         ssize_t length;
 378
 379         length = task_has_security(current, SECURITY__CHECK_CONTEXT);
 380         if (length)
 381                 return length;
 382
 383         length = security_context_to_sid(buf, size, &sid);
 384         if (length < 0)
 385                 return length;
 386
 387         length = security_sid_to_context(sid, &canon, &len);
 388         if (length < 0)
 389                 return length;
 390
 391         if (len > SIMPLE_TRANSACTION_LIMIT) {
 392                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
 393                         "payload max\n", __func__, len);
 394                 length = -ERANGE;
 395                 goto out;
 396         }
 397
 398         memcpy(buf, canon, len);
 399         length = len;
 400 out:
 401         kfree(canon);
 402         return length;
 403 }
 404
 405 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
 406                                      size_t count, loff_t *ppos)
 407 {
 408         char tmpbuf[TMPBUFLEN];
 409         ssize_t length;
 410
 411         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot);
 412         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 413 }
 414
 415 static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
 416                                       size_t count, loff_t *ppos)
 417 {
 418         char *page;
 419         ssize_t length;
 420         unsigned int new_value;
 421
 422         length = task_has_security(current, SECURITY__SETCHECKREQPROT);
 423         if (length)
 424                 return length;
 425
 426         if (count >= PAGE_SIZE)
 427                 return -ENOMEM;
 428         if (*ppos != 0) {
 429                 /* No partial writes. */
 430                 return -EINVAL;
 431         }
 432         page = (char *)get_zeroed_page(GFP_KERNEL);
 433         if (!page)
 434                 return -ENOMEM;
 435         length = -EFAULT;
 436         if (copy_from_user(page, buf, count))
 437                 goto out;
 438
 439         length = -EINVAL;
 440         if (sscanf(page, "%u", &new_value) != 1)
 441                 goto out;
 442
 443         selinux_checkreqprot = new_value ? 1 : 0;
 444         length = count;
 445 out:
 446         free_page((unsigned long) page);
 447         return length;
 448 }
 449 static const struct file_operations sel_checkreqprot_ops = {
 450         .read           = sel_read_checkreqprot,
 451         .write          = sel_write_checkreqprot,
 452 };
 453
 454 static ssize_t sel_read_compat_net(struct file *filp, char __user *buf,
 455                                    size_t count, loff_t *ppos)
 456 {
 457         char tmpbuf[TMPBUFLEN];
 458         ssize_t length;
 459
 460         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_compat_net);
 461         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 462 }
 463
 464 static ssize_t sel_write_compat_net(struct file *file, const char __user *buf,
 465                                     size_t count, loff_t *ppos)
 466 {
 467         char *page;
 468         ssize_t length;
 469         int new_value;
 470
 471         length = task_has_security(current, SECURITY__LOAD_POLICY);
 472         if (length)
 473                 return length;
 474
 475         if (count >= PAGE_SIZE)
 476                 return -ENOMEM;
 477         if (*ppos != 0) {
 478                 /* No partial writes. */
 479                 return -EINVAL;
 480         }
 481         page = (char *)get_zeroed_page(GFP_KERNEL);
 482         if (!page)
 483                 return -ENOMEM;
 484         length = -EFAULT;
 485         if (copy_from_user(page, buf, count))
 486                 goto out;
 487
 488         length = -EINVAL;
 489         if (sscanf(page, "%d", &new_value) != 1)
 490                 goto out;
 491
 492         selinux_compat_net = new_value ? 1 : 0;
 493         length = count;
 494 out:
 495         free_page((unsigned long) page);
 496         return length;
 497 }
 498 static const struct file_operations sel_compat_net_ops = {
 499         .read           = sel_read_compat_net,
 500         .write          = sel_write_compat_net,
 501 };
 502
 503 /*
 504  * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
 505  */
 506 static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
 507 static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
 508 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
 509 static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
 510 static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
 511
 512 static ssize_t (*write_op[])(struct file *, char *, size_t) = {
 513         [SEL_ACCESS] = sel_write_access,
 514         [SEL_CREATE] = sel_write_create,
 515         [SEL_RELABEL] = sel_write_relabel,
 516         [SEL_USER] = sel_write_user,
 517         [SEL_MEMBER] = sel_write_member,
 518         [SEL_CONTEXT] = sel_write_context,
 519 };
 520
 521 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
 522 {
 523         ino_t ino = file->f_path.dentry->d_inode->i_ino;
 524         char *data;
 525         ssize_t rv;
 526
 527         if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
 528                 return -EINVAL;
 529
 530         data = simple_transaction_get(file, buf, size);
 531         if (IS_ERR(data))
 532                 return PTR_ERR(data);
 533
 534         rv = write_op[ino](file, data, size);
 535         if (rv > 0) {
 536                 simple_transaction_set(file, rv);
 537                 rv = size;
 538         }
 539         return rv;
 540 }
 541
 542 static const struct file_operations transaction_ops = {
 543         .write          = selinux_transaction_write,
 544         .read           = simple_transaction_read,
 545         .release        = simple_transaction_release,
 546 };
 547
 548 /*
 549  * payload - write methods
 550  * If the method has a response, the response should be put in buf,
 551  * and the length returned.  Otherwise return 0 or and -error.
 552  */
 553
 554 static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
 555 {
 556         char *scon, *tcon;
 557         u32 ssid, tsid;
 558         u16 tclass;
 559         u32 req;
 560         struct av_decision avd;
 561         ssize_t length;
 562
 563         length = task_has_security(current, SECURITY__COMPUTE_AV);
 564         if (length)
 565                 return length;
 566
 567         length = -ENOMEM;
 568         scon = kzalloc(size+1, GFP_KERNEL);
 569         if (!scon)
 570                 return length;
 571
 572         tcon = kzalloc(size+1, GFP_KERNEL);
 573         if (!tcon)
 574                 goto out;
 575
 576         length = -EINVAL;
 577         if (sscanf(buf, "%s %s %hu %x", scon, tcon, &tclass, &req) != 4)
 578                 goto out2;
 579
 580         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
 581         if (length < 0)
 582                 goto out2;
 583         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
 584         if (length < 0)
 585                 goto out2;
 586
 587         length = security_compute_av(ssid, tsid, tclass, req, &avd);
 588         if (length < 0)
 589                 goto out2;
 590
 591         length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
 592                           "%x %x %x %x %u",
 593                           avd.allowed, avd.decided,
 594                           avd.auditallow, avd.auditdeny,
 595                           avd.seqno);
 596 out2:
 597         kfree(tcon);
 598 out:
 599         kfree(scon);
 600         return length;
 601 }
 602
 603 static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
 604 {
 605         char *scon, *tcon;
 606         u32 ssid, tsid, newsid;
 607         u16 tclass;
 608         ssize_t length;
 609         char *newcon;
 610         u32 len;
 611
 612         length = task_has_security(current, SECURITY__COMPUTE_CREATE);
 613         if (length)
 614                 return length;
 615
 616         length = -ENOMEM;
 617         scon = kzalloc(size+1, GFP_KERNEL);
 618         if (!scon)
 619                 return length;
 620
 621         tcon = kzalloc(size+1, GFP_KERNEL);
 622         if (!tcon)
 623                 goto out;
 624
 625         length = -EINVAL;
 626         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 627                 goto out2;
 628
 629         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
 630         if (length < 0)
 631                 goto out2;
 632         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
 633         if (length < 0)
 634                 goto out2;
 635
 636         length = security_transition_sid(ssid, tsid, tclass, &newsid);
 637         if (length < 0)
 638                 goto out2;
 639
 640         length = security_sid_to_context(newsid, &newcon, &len);
 641         if (length < 0)
 642                 goto out2;
 643
 644         if (len > SIMPLE_TRANSACTION_LIMIT) {
 645                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
 646                         "payload max\n", __func__, len);
 647                 length = -ERANGE;
 648                 goto out3;
 649         }
 650
 651         memcpy(buf, newcon, len);
 652         length = len;
 653 out3:
 654         kfree(newcon);
 655 out2:
 656         kfree(tcon);
 657 out:
 658         kfree(scon);
 659         return length;
 660 }
 661
 662 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
 663 {
 664         char *scon, *tcon;
 665         u32 ssid, tsid, newsid;
 666         u16 tclass;
 667         ssize_t length;
 668         char *newcon;
 669         u32 len;
 670
 671         length = task_has_security(current, SECURITY__COMPUTE_RELABEL);
 672         if (length)
 673                 return length;
 674
 675         length = -ENOMEM;
 676         scon = kzalloc(size+1, GFP_KERNEL);
 677         if (!scon)
 678                 return length;
 679
 680         tcon = kzalloc(size+1, GFP_KERNEL);
 681         if (!tcon)
 682                 goto out;
 683
 684         length = -EINVAL;
 685         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 686                 goto out2;
 687
 688         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
 689         if (length < 0)
 690                 goto out2;
 691         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
 692         if (length < 0)
 693                 goto out2;
 694
 695         length = security_change_sid(ssid, tsid, tclass, &newsid);
 696         if (length < 0)
 697                 goto out2;
 698
 699         length = security_sid_to_context(newsid, &newcon, &len);
 700         if (length < 0)
 701                 goto out2;
 702
 703         if (len > SIMPLE_TRANSACTION_LIMIT) {
 704                 length = -ERANGE;
 705                 goto out3;
 706         }
 707
 708         memcpy(buf, newcon, len);
 709         length = len;
 710 out3:
 711         kfree(newcon);
 712 out2:
 713         kfree(tcon);
 714 out:
 715         kfree(scon);
 716         return length;
 717 }
 718
 719 static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
 720 {
 721         char *con, *user, *ptr;
 722         u32 sid, *sids;
 723         ssize_t length;
 724         char *newcon;
 725         int i, rc;
 726         u32 len, nsids;
 727
 728         length = task_has_security(current, SECURITY__COMPUTE_USER);
 729         if (length)
 730                 return length;
 731
 732         length = -ENOMEM;
 733         con = kzalloc(size+1, GFP_KERNEL);
 734         if (!con)
 735                 return length;
 736
 737         user = kzalloc(size+1, GFP_KERNEL);
 738         if (!user)
 739                 goto out;
 740
 741         length = -EINVAL;
 742         if (sscanf(buf, "%s %s", con, user) != 2)
 743                 goto out2;
 744
 745         length = security_context_to_sid(con, strlen(con)+1, &sid);
 746         if (length < 0)
 747                 goto out2;
 748
 749         length = security_get_user_sids(sid, user, &sids, &nsids);
 750         if (length < 0)
 751                 goto out2;
 752
 753         length = sprintf(buf, "%u", nsids) + 1;
 754         ptr = buf + length;
 755         for (i = 0; i < nsids; i++) {
 756                 rc = security_sid_to_context(sids[i], &newcon, &len);
 757                 if (rc) {
 758                         length = rc;
 759                         goto out3;
 760                 }
 761                 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
 762                         kfree(newcon);
 763                         length = -ERANGE;
 764                         goto out3;
 765                 }
 766                 memcpy(ptr, newcon, len);
 767                 kfree(newcon);
 768                 ptr += len;
 769                 length += len;
 770         }
 771 out3:
 772         kfree(sids);
 773 out2:
 774         kfree(user);
 775 out:
 776         kfree(con);
 777         return length;
 778 }
 779
 780 static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
 781 {
 782         char *scon, *tcon;
 783         u32 ssid, tsid, newsid;
 784         u16 tclass;
 785         ssize_t length;
 786         char *newcon;
 787         u32 len;
 788
 789         length = task_has_security(current, SECURITY__COMPUTE_MEMBER);
 790         if (length)
 791                 return length;
 792
 793         length = -ENOMEM;
 794         scon = kzalloc(size+1, GFP_KERNEL);
 795         if (!scon)
 796                 return length;
 797
 798         tcon = kzalloc(size+1, GFP_KERNEL);
 799         if (!tcon)
 800                 goto out;
 801
 802         length = -EINVAL;
 803         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 804                 goto out2;
 805
 806         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
 807         if (length < 0)
 808                 goto out2;
 809         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
 810         if (length < 0)
 811                 goto out2;
 812
 813         length = security_member_sid(ssid, tsid, tclass, &newsid);
 814         if (length < 0)
 815                 goto out2;
 816
 817         length = security_sid_to_context(newsid, &newcon, &len);
 818         if (length < 0)
 819                 goto out2;
 820
 821         if (len > SIMPLE_TRANSACTION_LIMIT) {
 822                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
 823                         "payload max\n", __func__, len);
 824                 length = -ERANGE;
 825                 goto out3;
 826         }
 827
 828         memcpy(buf, newcon, len);
 829         length = len;
 830 out3:
 831         kfree(newcon);
 832 out2:
 833         kfree(tcon);
 834 out:
 835         kfree(scon);
 836         return length;
 837 }
 838
 839 static struct inode *sel_make_inode(struct super_block *sb, int mode)
 840 {
 841         struct inode *ret = new_inode(sb);
 842
 843         if (ret) {
 844                 ret->i_mode = mode;
 845                 ret->i_uid = ret->i_gid = 0;
 846                 ret->i_blocks = 0;
 847                 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
 848         }
 849         return ret;
 850 }
 851
 852 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
 853                              size_t count, loff_t *ppos)
 854 {
 855         char *page = NULL;
 856         ssize_t length;
 857         ssize_t ret;
 858         int cur_enforcing;
 859         struct inode *inode = filep->f_path.dentry->d_inode;
 860         unsigned index = inode->i_ino & SEL_INO_MASK;
 861         const char *name = filep->f_path.dentry->d_name.name;
 862
 863         mutex_lock(&sel_mutex);
 864
 865         if (index >= bool_num || strcmp(name, bool_pending_names[index])) {
 866                 ret = -EINVAL;
 867                 goto out;
 868         }
 869
 870         if (count > PAGE_SIZE) {
 871                 ret = -EINVAL;
 872                 goto out;
 873         }
 874         page = (char *)get_zeroed_page(GFP_KERNEL);
 875         if (!page) {
 876                 ret = -ENOMEM;
 877                 goto out;
 878         }
 879
 880         cur_enforcing = security_get_bool_value(index);
 881         if (cur_enforcing < 0) {
 882                 ret = cur_enforcing;
 883                 goto out;
 884         }
 885         length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
 886                           bool_pending_values[index]);
 887         ret = simple_read_from_buffer(buf, count, ppos, page, length);
 888 out:
 889         mutex_unlock(&sel_mutex);
 890         if (page)
 891                 free_page((unsigned long)page);
 892         return ret;
 893 }
 894
 895 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
 896                               size_t count, loff_t *ppos)
 897 {
 898         char *page = NULL;
 899         ssize_t length;
 900         int new_value;
 901         struct inode *inode = filep->f_path.dentry->d_inode;
 902         unsigned index = inode->i_ino & SEL_INO_MASK;
 903         const char *name = filep->f_path.dentry->d_name.name;
 904
 905         mutex_lock(&sel_mutex);
 906
 907         length = task_has_security(current, SECURITY__SETBOOL);
 908         if (length)
 909                 goto out;
 910
 911         if (index >= bool_num || strcmp(name, bool_pending_names[index])) {
 912                 length = -EINVAL;
 913                 goto out;
 914         }
 915
 916         if (count >= PAGE_SIZE) {
 917                 length = -ENOMEM;
 918                 goto out;
 919         }
 920
 921         if (*ppos != 0) {
 922                 /* No partial writes. */
 923                 length = -EINVAL;
 924                 goto out;
 925         }
 926         page = (char *)get_zeroed_page(GFP_KERNEL);
 927         if (!page) {
 928                 length = -ENOMEM;
 929                 goto out;
 930         }
 931
 932         length = -EFAULT;
 933         if (copy_from_user(page, buf, count))
 934                 goto out;
 935
 936         length = -EINVAL;
 937         if (sscanf(page, "%d", &new_value) != 1)
 938                 goto out;
 939
 940         if (new_value)
 941                 new_value = 1;
 942
 943         bool_pending_values[index] = new_value;
 944         length = count;
 945
 946 out:
 947         mutex_unlock(&sel_mutex);
 948         if (page)
 949                 free_page((unsigned long) page);
 950         return length;
 951 }
 952
 953 static const struct file_operations sel_bool_ops = {
 954         .read           = sel_read_bool,
 955         .write          = sel_write_bool,
 956 };
 957
 958 static ssize_t sel_commit_bools_write(struct file *filep,
 959                                       const char __user *buf,
 960                                       size_t count, loff_t *ppos)
 961 {
 962         char *page = NULL;
 963         ssize_t length;
 964         int new_value;
 965
 966         mutex_lock(&sel_mutex);
 967
 968         length = task_has_security(current, SECURITY__SETBOOL);
 969         if (length)
 970                 goto out;
 971
 972         if (count >= PAGE_SIZE) {
 973                 length = -ENOMEM;
 974                 goto out;
 975         }
 976         if (*ppos != 0) {
 977                 /* No partial writes. */
 978                 goto out;
 979         }
 980         page = (char *)get_zeroed_page(GFP_KERNEL);
 981         if (!page) {
 982                 length = -ENOMEM;
 983                 goto out;
 984         }
 985
 986         length = -EFAULT;
 987         if (copy_from_user(page, buf, count))
 988                 goto out;
 989
 990         length = -EINVAL;
 991         if (sscanf(page, "%d", &new_value) != 1)
 992                 goto out;
 993
 994         if (new_value && bool_pending_values)
 995                 security_set_bools(bool_num, bool_pending_values);
 996
 997         length = count;
 998
 999 out:
1000         mutex_unlock(&sel_mutex);
1001         if (page)
1002                 free_page((unsigned long) page);
1003         return length;
1004 }
1005
1006 static const struct file_operations sel_commit_bools_ops = {
1007         .write          = sel_commit_bools_write,
1008 };
1009
1010 static void sel_remove_entries(struct dentry *de)
1011 {
1012         struct list_head *node;
1013
1014         spin_lock(&dcache_lock);
1015         node = de->d_subdirs.next;
1016         while (node != &de->d_subdirs) {
1017                 struct dentry *d = list_entry(node, struct dentry, d_u.d_child);
1018                 list_del_init(node);
1019
1020                 if (d->d_inode) {
1021                         d = dget_locked(d);
1022                         spin_unlock(&dcache_lock);
1023                         d_delete(d);
1024                         simple_unlink(de->d_inode, d);
1025                         dput(d);
1026                         spin_lock(&dcache_lock);
1027                 }
1028                 node = de->d_subdirs.next;
1029         }
1030
1031         spin_unlock(&dcache_lock);
1032 }
1033
1034 #define BOOL_DIR_NAME "booleans"
1035
1036 static int sel_make_bools(void)
1037 {
1038         int i, ret = 0;
1039         ssize_t len;
1040         struct dentry *dentry = NULL;
1041         struct dentry *dir = bool_dir;
1042         struct inode *inode = NULL;
1043         struct inode_security_struct *isec;
1044         char **names = NULL, *page;
1045         int num;
1046         int *values = NULL;
1047         u32 sid;
1048
1049         /* remove any existing files */
1050         kfree(bool_pending_names);
1051         kfree(bool_pending_values);
1052         bool_pending_names = NULL;
1053         bool_pending_values = NULL;
1054
1055         sel_remove_entries(dir);
1056
1057         page = (char *)get_zeroed_page(GFP_KERNEL);
1058         if (!page)
1059                 return -ENOMEM;
1060
1061         ret = security_get_bools(&num, &names, &values);
1062         if (ret != 0)
1063                 goto out;
1064
1065         for (i = 0; i < num; i++) {
1066                 dentry = d_alloc_name(dir, names[i]);
1067                 if (!dentry) {
1068                         ret = -ENOMEM;
1069                         goto err;
1070                 }
1071                 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1072                 if (!inode) {
1073                         ret = -ENOMEM;
1074                         goto err;
1075                 }
1076
1077                 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1078                 if (len < 0) {
1079                         ret = -EINVAL;
1080                         goto err;
1081                 } else if (len >= PAGE_SIZE) {
1082                         ret = -ENAMETOOLONG;
1083                         goto err;
1084                 }
1085                 isec = (struct inode_security_struct *)inode->i_security;
1086                 ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid);
1087                 if (ret)
1088                         goto err;
1089                 isec->sid = sid;
1090                 isec->initialized = 1;
1091                 inode->i_fop = &sel_bool_ops;
1092                 inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1093                 d_add(dentry, inode);
1094         }
1095         bool_num = num;
1096         bool_pending_names = names;
1097         bool_pending_values = values;
1098 out:
1099         free_page((unsigned long)page);
1100         return ret;
1101 err:
1102         if (names) {
1103                 for (i = 0; i < num; i++)
1104                         kfree(names[i]);
1105                 kfree(names);
1106         }
1107         kfree(values);
1108         sel_remove_entries(dir);
1109         ret = -ENOMEM;
1110         goto out;
1111 }
1112
1113 #define NULL_FILE_NAME "null"
1114
1115 struct dentry *selinux_null;
1116
1117 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1118                                             size_t count, loff_t *ppos)
1119 {
1120         char tmpbuf[TMPBUFLEN];
1121         ssize_t length;
1122
1123         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
1124         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1125 }
1126
1127 static ssize_t sel_write_avc_cache_threshold(struct file *file,
1128                                              const char __user *buf,
1129                                              size_t count, loff_t *ppos)
1130
1131 {
1132         char *page;
1133         ssize_t ret;
1134         int new_value;
1135
1136         if (count >= PAGE_SIZE) {
1137                 ret = -ENOMEM;
1138                 goto out;
1139         }
1140
1141         if (*ppos != 0) {
1142                 /* No partial writes. */
1143                 ret = -EINVAL;
1144                 goto out;
1145         }
1146
1147         page = (char *)get_zeroed_page(GFP_KERNEL);
1148         if (!page) {
1149                 ret = -ENOMEM;
1150                 goto out;
1151         }
1152
1153         if (copy_from_user(page, buf, count)) {
1154                 ret = -EFAULT;
1155                 goto out_free;
1156         }
1157
1158         if (sscanf(page, "%u", &new_value) != 1) {
1159                 ret = -EINVAL;
1160                 goto out;
1161         }
1162
1163         if (new_value != avc_cache_threshold) {
1164                 ret = task_has_security(current, SECURITY__SETSECPARAM);
1165                 if (ret)
1166                         goto out_free;
1167                 avc_cache_threshold = new_value;
1168         }
1169         ret = count;
1170 out_free:
1171         free_page((unsigned long)page);
1172 out:
1173         return ret;
1174 }
1175
1176 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1177                                        size_t count, loff_t *ppos)
1178 {
1179         char *page;
1180         ssize_t ret = 0;
1181
1182         page = (char *)__get_free_page(GFP_KERNEL);
1183         if (!page) {
1184                 ret = -ENOMEM;
1185                 goto out;
1186         }
1187         ret = avc_get_hash_stats(page);
1188         if (ret >= 0)
1189                 ret = simple_read_from_buffer(buf, count, ppos, page, ret);
1190         free_page((unsigned long)page);
1191 out:
1192         return ret;
1193 }
1194
1195 static const struct file_operations sel_avc_cache_threshold_ops = {
1196         .read           = sel_read_avc_cache_threshold,
1197         .write          = sel_write_avc_cache_threshold,
1198 };
1199
1200 static const struct file_operations sel_avc_hash_stats_ops = {
1201         .read           = sel_read_avc_hash_stats,
1202 };
1203
1204 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1205 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1206 {
1207         int cpu;
1208
1209         for (cpu = *idx; cpu < NR_CPUS; ++cpu) {
1210                 if (!cpu_possible(cpu))
1211                         continue;
1212                 *idx = cpu + 1;
1213                 return &per_cpu(avc_cache_stats, cpu);
1214         }
1215         return NULL;
1216 }
1217
1218 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1219 {
1220         loff_t n = *pos - 1;
1221
1222         if (*pos == 0)
1223                 return SEQ_START_TOKEN;
1224
1225         return sel_avc_get_stat_idx(&n);
1226 }
1227
1228 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1229 {
1230         return sel_avc_get_stat_idx(pos);
1231 }
1232
1233 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1234 {
1235         struct avc_cache_stats *st = v;
1236
1237         if (v == SEQ_START_TOKEN)
1238                 seq_printf(seq, "lookups hits misses allocations reclaims "
1239                            "frees\n");
1240         else
1241                 seq_printf(seq, "%u %u %u %u %u %u\n", st->lookups,
1242                            st->hits, st->misses, st->allocations,
1243                            st->reclaims, st->frees);
1244         return 0;
1245 }
1246
1247 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1248 { }
1249
1250 static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1251         .start          = sel_avc_stats_seq_start,
1252         .next           = sel_avc_stats_seq_next,
1253         .show           = sel_avc_stats_seq_show,
1254         .stop           = sel_avc_stats_seq_stop,
1255 };
1256
1257 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1258 {
1259         return seq_open(file, &sel_avc_cache_stats_seq_ops);
1260 }
1261
1262 static const struct file_operations sel_avc_cache_stats_ops = {
1263         .open           = sel_open_avc_cache_stats,
1264         .read           = seq_read,
1265         .llseek         = seq_lseek,
1266         .release        = seq_release,
1267 };
1268 #endif
1269
1270 static int sel_make_avc_files(struct dentry *dir)
1271 {
1272         int i, ret = 0;
1273         static struct tree_descr files[] = {
1274                 { "cache_threshold",
1275                   &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1276                 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1277 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1278                 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1279 #endif
1280         };
1281
1282         for (i = 0; i < ARRAY_SIZE(files); i++) {
1283                 struct inode *inode;
1284                 struct dentry *dentry;
1285
1286                 dentry = d_alloc_name(dir, files[i].name);
1287                 if (!dentry) {
1288                         ret = -ENOMEM;
1289                         goto out;
1290                 }
1291
1292                 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1293                 if (!inode) {
1294                         ret = -ENOMEM;
1295                         goto out;
1296                 }
1297                 inode->i_fop = files[i].ops;
1298                 inode->i_ino = ++sel_last_ino;
1299                 d_add(dentry, inode);
1300         }
1301 out:
1302         return ret;
1303 }
1304
1305 static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1306                                 size_t count, loff_t *ppos)
1307 {
1308         struct inode *inode;
1309         char *con;
1310         u32 sid, len;
1311         ssize_t ret;
1312
1313         inode = file->f_path.dentry->d_inode;
1314         sid = inode->i_ino&SEL_INO_MASK;
1315         ret = security_sid_to_context(sid, &con, &len);
1316         if (ret < 0)
1317                 return ret;
1318
1319         ret = simple_read_from_buffer(buf, count, ppos, con, len);
1320         kfree(con);
1321         return ret;
1322 }
1323
1324 static const struct file_operations sel_initcon_ops = {
1325         .read           = sel_read_initcon,
1326 };
1327
1328 static int sel_make_initcon_files(struct dentry *dir)
1329 {
1330         int i, ret = 0;
1331
1332         for (i = 1; i <= SECINITSID_NUM; i++) {
1333                 struct inode *inode;
1334                 struct dentry *dentry;
1335                 dentry = d_alloc_name(dir, security_get_initial_sid_context(i));
1336                 if (!dentry) {
1337                         ret = -ENOMEM;
1338                         goto out;
1339                 }
1340
1341                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1342                 if (!inode) {
1343                         ret = -ENOMEM;
1344                         goto out;
1345                 }
1346                 inode->i_fop = &sel_initcon_ops;
1347                 inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1348                 d_add(dentry, inode);
1349         }
1350 out:
1351         return ret;
1352 }
1353
1354 static inline unsigned int sel_div(unsigned long a, unsigned long b)
1355 {
1356         return a / b - (a % b < 0);
1357 }
1358
1359 static inline unsigned long sel_class_to_ino(u16 class)
1360 {
1361         return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1362 }
1363
1364 static inline u16 sel_ino_to_class(unsigned long ino)
1365 {
1366         return sel_div(ino & SEL_INO_MASK, SEL_VEC_MAX + 1);
1367 }
1368
1369 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1370 {
1371         return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1372 }
1373
1374 static inline u32 sel_ino_to_perm(unsigned long ino)
1375 {
1376         return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1377 }
1378
1379 static ssize_t sel_read_class(struct file *file, char __user *buf,
1380                                 size_t count, loff_t *ppos)
1381 {
1382         ssize_t rc, len;
1383         char *page;
1384         unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1385
1386         page = (char *)__get_free_page(GFP_KERNEL);
1387         if (!page) {
1388                 rc = -ENOMEM;
1389                 goto out;
1390         }
1391
1392         len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_class(ino));
1393         rc = simple_read_from_buffer(buf, count, ppos, page, len);
1394         free_page((unsigned long)page);
1395 out:
1396         return rc;
1397 }
1398
1399 static const struct file_operations sel_class_ops = {
1400         .read           = sel_read_class,
1401 };
1402
1403 static ssize_t sel_read_perm(struct file *file, char __user *buf,
1404                                 size_t count, loff_t *ppos)
1405 {
1406         ssize_t rc, len;
1407         char *page;
1408         unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1409
1410         page = (char *)__get_free_page(GFP_KERNEL);
1411         if (!page) {
1412                 rc = -ENOMEM;
1413                 goto out;
1414         }
1415
1416         len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_perm(ino));
1417         rc = simple_read_from_buffer(buf, count, ppos, page, len);
1418         free_page((unsigned long)page);
1419 out:
1420         return rc;
1421 }
1422
1423 static const struct file_operations sel_perm_ops = {
1424         .read           = sel_read_perm,
1425 };
1426
1427 static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1428                                   size_t count, loff_t *ppos)
1429 {
1430         int value;
1431         char tmpbuf[TMPBUFLEN];
1432         ssize_t length;
1433         unsigned long i_ino = file->f_path.dentry->d_inode->i_ino;
1434
1435         value = security_policycap_supported(i_ino & SEL_INO_MASK);
1436         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
1437
1438         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1439 }
1440
1441 static const struct file_operations sel_policycap_ops = {
1442         .read           = sel_read_policycap,
1443 };
1444
1445 static int sel_make_perm_files(char *objclass, int classvalue,
1446                                 struct dentry *dir)
1447 {
1448         int i, rc = 0, nperms;
1449         char **perms;
1450
1451         rc = security_get_permissions(objclass, &perms, &nperms);
1452         if (rc)
1453                 goto out;
1454
1455         for (i = 0; i < nperms; i++) {
1456                 struct inode *inode;
1457                 struct dentry *dentry;
1458
1459                 dentry = d_alloc_name(dir, perms[i]);
1460                 if (!dentry) {
1461                         rc = -ENOMEM;
1462                         goto out1;
1463                 }
1464
1465                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1466                 if (!inode) {
1467                         rc = -ENOMEM;
1468                         goto out1;
1469                 }
1470                 inode->i_fop = &sel_perm_ops;
1471                 /* i+1 since perm values are 1-indexed */
1472                 inode->i_ino = sel_perm_to_ino(classvalue, i+1);
1473                 d_add(dentry, inode);
1474         }
1475
1476 out1:
1477         for (i = 0; i < nperms; i++)
1478                 kfree(perms[i]);
1479         kfree(perms);
1480 out:
1481         return rc;
1482 }
1483
1484 static int sel_make_class_dir_entries(char *classname, int index,
1485                                         struct dentry *dir)
1486 {
1487         struct dentry *dentry = NULL;
1488         struct inode *inode = NULL;
1489         int rc;
1490
1491         dentry = d_alloc_name(dir, "index");
1492         if (!dentry) {
1493                 rc = -ENOMEM;
1494                 goto out;
1495         }
1496
1497         inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1498         if (!inode) {
1499                 rc = -ENOMEM;
1500                 goto out;
1501         }
1502
1503         inode->i_fop = &sel_class_ops;
1504         inode->i_ino = sel_class_to_ino(index);
1505         d_add(dentry, inode);
1506
1507         dentry = d_alloc_name(dir, "perms");
1508         if (!dentry) {
1509                 rc = -ENOMEM;
1510                 goto out;
1511         }
1512
1513         rc = sel_make_dir(dir->d_inode, dentry, &last_class_ino);
1514         if (rc)
1515                 goto out;
1516
1517         rc = sel_make_perm_files(classname, index, dentry);
1518
1519 out:
1520         return rc;
1521 }
1522
1523 static void sel_remove_classes(void)
1524 {
1525         struct list_head *class_node;
1526
1527         list_for_each(class_node, &class_dir->d_subdirs) {
1528                 struct dentry *class_subdir = list_entry(class_node,
1529                                         struct dentry, d_u.d_child);
1530                 struct list_head *class_subdir_node;
1531
1532                 list_for_each(class_subdir_node, &class_subdir->d_subdirs) {
1533                         struct dentry *d = list_entry(class_subdir_node,
1534                                                 struct dentry, d_u.d_child);
1535
1536                         if (d->d_inode)
1537                                 if (d->d_inode->i_mode & S_IFDIR)
1538                                         sel_remove_entries(d);
1539                 }
1540
1541                 sel_remove_entries(class_subdir);
1542         }
1543
1544         sel_remove_entries(class_dir);
1545 }
1546
1547 static int sel_make_classes(void)
1548 {
1549         int rc = 0, nclasses, i;
1550         char **classes;
1551
1552         /* delete any existing entries */
1553         sel_remove_classes();
1554
1555         rc = security_get_classes(&classes, &nclasses);
1556         if (rc < 0)
1557                 goto out;
1558
1559         /* +2 since classes are 1-indexed */
1560         last_class_ino = sel_class_to_ino(nclasses+2);
1561
1562         for (i = 0; i < nclasses; i++) {
1563                 struct dentry *class_name_dir;
1564
1565                 class_name_dir = d_alloc_name(class_dir, classes[i]);
1566                 if (!class_name_dir) {
1567                         rc = -ENOMEM;
1568                         goto out1;
1569                 }
1570
1571                 rc = sel_make_dir(class_dir->d_inode, class_name_dir,
1572                                 &last_class_ino);
1573                 if (rc)
1574                         goto out1;
1575
1576                 /* i+1 since class values are 1-indexed */
1577                 rc = sel_make_class_dir_entries(classes[i], i+1,
1578                                 class_name_dir);
1579                 if (rc)
1580                         goto out1;
1581         }
1582
1583 out1:
1584         for (i = 0; i < nclasses; i++)
1585                 kfree(classes[i]);
1586         kfree(classes);
1587 out:
1588         return rc;
1589 }
1590
1591 static int sel_make_policycap(void)
1592 {
1593         unsigned int iter;
1594         struct dentry *dentry = NULL;
1595         struct inode *inode = NULL;
1596
1597         sel_remove_entries(policycap_dir);
1598
1599         for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) {
1600                 if (iter < ARRAY_SIZE(policycap_names))
1601                         dentry = d_alloc_name(policycap_dir,
1602                                               policycap_names[iter]);
1603                 else
1604                         dentry = d_alloc_name(policycap_dir, "unknown");
1605
1606                 if (dentry == NULL)
1607                         return -ENOMEM;
1608
1609                 inode = sel_make_inode(policycap_dir->d_sb, S_IFREG | S_IRUGO);
1610                 if (inode == NULL)
1611                         return -ENOMEM;
1612
1613                 inode->i_fop = &sel_policycap_ops;
1614                 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
1615                 d_add(dentry, inode);
1616         }
1617
1618         return 0;
1619 }
1620
1621 static int sel_make_dir(struct inode *dir, struct dentry *dentry,
1622                         unsigned long *ino)
1623 {
1624         int ret = 0;
1625         struct inode *inode;
1626
1627         inode = sel_make_inode(dir->i_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1628         if (!inode) {
1629                 ret = -ENOMEM;
1630                 goto out;
1631         }
1632         inode->i_op = &simple_dir_inode_operations;
1633         inode->i_fop = &simple_dir_operations;
1634         inode->i_ino = ++(*ino);
1635         /* directory inodes start off with i_nlink == 2 (for "." entry) */
1636         inc_nlink(inode);
1637         d_add(dentry, inode);
1638         /* bump link count on parent directory, too */
1639         inc_nlink(dir);
1640 out:
1641         return ret;
1642 }
1643
1644 static int sel_fill_super(struct super_block *sb, void *data, int silent)
1645 {
1646         int ret;
1647         struct dentry *dentry;
1648         struct inode *inode, *root_inode;
1649         struct inode_security_struct *isec;
1650
1651         static struct tree_descr selinux_files[] = {
1652                 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1653                 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1654                 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1655                 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1656                 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1657                 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1658                 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1659                 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1660                 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1661                 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1662                 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1663                 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1664                 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1665                 [SEL_COMPAT_NET] = {"compat_net", &sel_compat_net_ops, S_IRUGO|S_IWUSR},
1666                 [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
1667                 [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
1668                 /* last one */ {""}
1669         };
1670         ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1671         if (ret)
1672                 goto err;
1673
1674         root_inode = sb->s_root->d_inode;
1675
1676         dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME);
1677         if (!dentry) {
1678                 ret = -ENOMEM;
1679                 goto err;
1680         }
1681
1682         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1683         if (ret)
1684                 goto err;
1685
1686         bool_dir = dentry;
1687
1688         dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1689         if (!dentry) {
1690                 ret = -ENOMEM;
1691                 goto err;
1692         }
1693
1694         inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1695         if (!inode) {
1696                 ret = -ENOMEM;
1697                 goto err;
1698         }
1699         inode->i_ino = ++sel_last_ino;
1700         isec = (struct inode_security_struct *)inode->i_security;
1701         isec->sid = SECINITSID_DEVNULL;
1702         isec->sclass = SECCLASS_CHR_FILE;
1703         isec->initialized = 1;
1704
1705         init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1706         d_add(dentry, inode);
1707         selinux_null = dentry;
1708
1709         dentry = d_alloc_name(sb->s_root, "avc");
1710         if (!dentry) {
1711                 ret = -ENOMEM;
1712                 goto err;
1713         }
1714
1715         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1716         if (ret)
1717                 goto err;
1718
1719         ret = sel_make_avc_files(dentry);
1720         if (ret)
1721                 goto err;
1722
1723         dentry = d_alloc_name(sb->s_root, "initial_contexts");
1724         if (!dentry) {
1725                 ret = -ENOMEM;
1726                 goto err;
1727         }
1728
1729         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1730         if (ret)
1731                 goto err;
1732
1733         ret = sel_make_initcon_files(dentry);
1734         if (ret)
1735                 goto err;
1736
1737         dentry = d_alloc_name(sb->s_root, "class");
1738         if (!dentry) {
1739                 ret = -ENOMEM;
1740                 goto err;
1741         }
1742
1743         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1744         if (ret)
1745                 goto err;
1746
1747         class_dir = dentry;
1748
1749         dentry = d_alloc_name(sb->s_root, "policy_capabilities");
1750         if (!dentry) {
1751                 ret = -ENOMEM;
1752                 goto err;
1753         }
1754
1755         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1756         if (ret)
1757                 goto err;
1758
1759         policycap_dir = dentry;
1760
1761 out:
1762         return ret;
1763 err:
1764         printk(KERN_ERR "SELinux: %s:  failed while creating inodes\n",
1765                 __func__);
1766         goto out;
1767 }
1768
1769 static int sel_get_sb(struct file_system_type *fs_type,
1770                       int flags, const char *dev_name, void *data,
1771                       struct vfsmount *mnt)
1772 {
1773         return get_sb_single(fs_type, flags, data, sel_fill_super, mnt);
1774 }
1775
1776 static struct file_system_type sel_fs_type = {
1777         .name           = "selinuxfs",
1778         .get_sb         = sel_get_sb,
1779         .kill_sb        = kill_litter_super,
1780 };
1781
1782 struct vfsmount *selinuxfs_mount;
1783
1784 static int __init init_sel_fs(void)
1785 {
1786         int err;
1787
1788         if (!selinux_enabled)
1789                 return 0;
1790         err = register_filesystem(&sel_fs_type);
1791         if (!err) {
1792                 selinuxfs_mount = kern_mount(&sel_fs_type);
1793                 if (IS_ERR(selinuxfs_mount)) {
1794                         printk(KERN_ERR "selinuxfs:  could not mount!\n");
1795                         err = PTR_ERR(selinuxfs_mount);
1796                         selinuxfs_mount = NULL;
1797                 }
1798         }
1799         return err;
1800 }
1801
1802 __initcall(init_sel_fs);
1803
1804 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
1805 void exit_sel_fs(void)
1806 {
1807         unregister_filesystem(&sel_fs_type);
1808 }
1809 #endif