security/selinux/selinuxfs.c

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