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