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