linux/security/selinux/selinuxfs.c
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   1/* Updated: Karl MacMillan <kmacmillan@tresys.com>
   2 *
   3 *      Added conditional policy language extensions
   4 *
   5 *  Updated: Hewlett-Packard <paul@paul-moore.com>
   6 *
   7 *      Added support for the policy capability bitmap
   8 *
   9 * Copyright (C) 2007 Hewlett-Packard Development Company, L.P.
  10 * Copyright (C) 2003 - 2004 Tresys Technology, LLC
  11 * Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
  12 *      This program is free software; you can redistribute it and/or modify
  13 *      it under the terms of the GNU General Public License as published by
  14 *      the Free Software Foundation, version 2.
  15 */
  16
  17#include <linux/kernel.h>
  18#include <linux/pagemap.h>
  19#include <linux/slab.h>
  20#include <linux/vmalloc.h>
  21#include <linux/fs.h>
  22#include <linux/mutex.h>
  23#include <linux/init.h>
  24#include <linux/string.h>
  25#include <linux/security.h>
  26#include <linux/major.h>
  27#include <linux/seq_file.h>
  28#include <linux/percpu.h>
  29#include <linux/audit.h>
  30#include <linux/uaccess.h>
  31#include <linux/kobject.h>
  32#include <linux/ctype.h>
  33
  34/* selinuxfs pseudo filesystem for exporting the security policy API.
  35   Based on the proc code and the fs/nfsd/nfsctl.c code. */
  36
  37#include "flask.h"
  38#include "avc.h"
  39#include "avc_ss.h"
  40#include "security.h"
  41#include "objsec.h"
  42#include "conditional.h"
  43
  44/* Policy capability filenames */
  45static char *policycap_names[] = {
  46        "network_peer_controls",
  47        "open_perms",
  48        "redhat1",
  49        "always_check_network"
  50};
  51
  52unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
  53
  54static int __init checkreqprot_setup(char *str)
  55{
  56        unsigned long checkreqprot;
  57        if (!kstrtoul(str, 0, &checkreqprot))
  58                selinux_checkreqprot = checkreqprot ? 1 : 0;
  59        return 1;
  60}
  61__setup("checkreqprot=", checkreqprot_setup);
  62
  63static DEFINE_MUTEX(sel_mutex);
  64
  65/* global data for booleans */
  66static struct dentry *bool_dir;
  67static int bool_num;
  68static char **bool_pending_names;
  69static int *bool_pending_values;
  70
  71/* global data for classes */
  72static struct dentry *class_dir;
  73static unsigned long last_class_ino;
  74
  75static char policy_opened;
  76
  77/* global data for policy capabilities */
  78static struct dentry *policycap_dir;
  79
  80/* Check whether a task is allowed to use a security operation. */
  81static int task_has_security(struct task_struct *tsk,
  82                             u32 perms)
  83{
  84        const struct task_security_struct *tsec;
  85        u32 sid = 0;
  86
  87        rcu_read_lock();
  88        tsec = __task_cred(tsk)->security;
  89        if (tsec)
  90                sid = tsec->sid;
  91        rcu_read_unlock();
  92        if (!tsec)
  93                return -EACCES;
  94
  95        return avc_has_perm(sid, SECINITSID_SECURITY,
  96                            SECCLASS_SECURITY, perms, NULL);
  97}
  98
  99enum sel_inos {
 100        SEL_ROOT_INO = 2,
 101        SEL_LOAD,       /* load policy */
 102        SEL_ENFORCE,    /* get or set enforcing status */
 103        SEL_CONTEXT,    /* validate context */
 104        SEL_ACCESS,     /* compute access decision */
 105        SEL_CREATE,     /* compute create labeling decision */
 106        SEL_RELABEL,    /* compute relabeling decision */
 107        SEL_USER,       /* compute reachable user contexts */
 108        SEL_POLICYVERS, /* return policy version for this kernel */
 109        SEL_COMMIT_BOOLS, /* commit new boolean values */
 110        SEL_MLS,        /* return if MLS policy is enabled */
 111        SEL_DISABLE,    /* disable SELinux until next reboot */
 112        SEL_MEMBER,     /* compute polyinstantiation membership decision */
 113        SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
 114        SEL_COMPAT_NET, /* whether to use old compat network packet controls */
 115        SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */
 116        SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */
 117        SEL_STATUS,     /* export current status using mmap() */
 118        SEL_POLICY,     /* allow userspace to read the in kernel policy */
 119        SEL_VALIDATE_TRANS, /* compute validatetrans decision */
 120        SEL_INO_NEXT,   /* The next inode number to use */
 121};
 122
 123static unsigned long sel_last_ino = SEL_INO_NEXT - 1;
 124
 125#define SEL_INITCON_INO_OFFSET          0x01000000
 126#define SEL_BOOL_INO_OFFSET             0x02000000
 127#define SEL_CLASS_INO_OFFSET            0x04000000
 128#define SEL_POLICYCAP_INO_OFFSET        0x08000000
 129#define SEL_INO_MASK                    0x00ffffff
 130
 131#define TMPBUFLEN       12
 132static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
 133                                size_t count, loff_t *ppos)
 134{
 135        char tmpbuf[TMPBUFLEN];
 136        ssize_t length;
 137
 138        length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing);
 139        return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 140}
 141
 142#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 143static ssize_t sel_write_enforce(struct file *file, const char __user *buf,
 144                                 size_t count, loff_t *ppos)
 145
 146{
 147        char *page = NULL;
 148        ssize_t length;
 149        int new_value;
 150
 151        if (count >= PAGE_SIZE)
 152                return -ENOMEM;
 153
 154        /* No partial writes. */
 155        if (*ppos != 0)
 156                return -EINVAL;
 157
 158        page = memdup_user_nul(buf, count);
 159        if (IS_ERR(page))
 160                return PTR_ERR(page);
 161
 162        length = -EINVAL;
 163        if (sscanf(page, "%d", &new_value) != 1)
 164                goto out;
 165
 166        if (new_value != selinux_enforcing) {
 167                length = task_has_security(current, SECURITY__SETENFORCE);
 168                if (length)
 169                        goto out;
 170                audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
 171                        "enforcing=%d old_enforcing=%d auid=%u ses=%u",
 172                        new_value, selinux_enforcing,
 173                        from_kuid(&init_user_ns, audit_get_loginuid(current)),
 174                        audit_get_sessionid(current));
 175                selinux_enforcing = new_value;
 176                if (selinux_enforcing)
 177                        avc_ss_reset(0);
 178                selnl_notify_setenforce(selinux_enforcing);
 179                selinux_status_update_setenforce(selinux_enforcing);
 180        }
 181        length = count;
 182out:
 183        kfree(page);
 184        return length;
 185}
 186#else
 187#define sel_write_enforce NULL
 188#endif
 189
 190static const struct file_operations sel_enforce_ops = {
 191        .read           = sel_read_enforce,
 192        .write          = sel_write_enforce,
 193        .llseek         = generic_file_llseek,
 194};
 195
 196static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
 197                                        size_t count, loff_t *ppos)
 198{
 199        char tmpbuf[TMPBUFLEN];
 200        ssize_t length;
 201        ino_t ino = file_inode(filp)->i_ino;
 202        int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ?
 203                security_get_reject_unknown() : !security_get_allow_unknown();
 204
 205        length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown);
 206        return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 207}
 208
 209static const struct file_operations sel_handle_unknown_ops = {
 210        .read           = sel_read_handle_unknown,
 211        .llseek         = generic_file_llseek,
 212};
 213
 214static int sel_open_handle_status(struct inode *inode, struct file *filp)
 215{
 216        struct page    *status = selinux_kernel_status_page();
 217
 218        if (!status)
 219                return -ENOMEM;
 220
 221        filp->private_data = status;
 222
 223        return 0;
 224}
 225
 226static ssize_t sel_read_handle_status(struct file *filp, char __user *buf,
 227                                      size_t count, loff_t *ppos)
 228{
 229        struct page    *status = filp->private_data;
 230
 231        BUG_ON(!status);
 232
 233        return simple_read_from_buffer(buf, count, ppos,
 234                                       page_address(status),
 235                                       sizeof(struct selinux_kernel_status));
 236}
 237
 238static int sel_mmap_handle_status(struct file *filp,
 239                                  struct vm_area_struct *vma)
 240{
 241        struct page    *status = filp->private_data;
 242        unsigned long   size = vma->vm_end - vma->vm_start;
 243
 244        BUG_ON(!status);
 245
 246        /* only allows one page from the head */
 247        if (vma->vm_pgoff > 0 || size != PAGE_SIZE)
 248                return -EIO;
 249        /* disallow writable mapping */
 250        if (vma->vm_flags & VM_WRITE)
 251                return -EPERM;
 252        /* disallow mprotect() turns it into writable */
 253        vma->vm_flags &= ~VM_MAYWRITE;
 254
 255        return remap_pfn_range(vma, vma->vm_start,
 256                               page_to_pfn(status),
 257                               size, vma->vm_page_prot);
 258}
 259
 260static const struct file_operations sel_handle_status_ops = {
 261        .open           = sel_open_handle_status,
 262        .read           = sel_read_handle_status,
 263        .mmap           = sel_mmap_handle_status,
 264        .llseek         = generic_file_llseek,
 265};
 266
 267#ifdef CONFIG_SECURITY_SELINUX_DISABLE
 268static ssize_t sel_write_disable(struct file *file, const char __user *buf,
 269                                 size_t count, loff_t *ppos)
 270
 271{
 272        char *page;
 273        ssize_t length;
 274        int new_value;
 275
 276        if (count >= PAGE_SIZE)
 277                return -ENOMEM;
 278
 279        /* No partial writes. */
 280        if (*ppos != 0)
 281                return -EINVAL;
 282
 283        page = memdup_user_nul(buf, count);
 284        if (IS_ERR(page))
 285                return PTR_ERR(page);
 286
 287        length = -EINVAL;
 288        if (sscanf(page, "%d", &new_value) != 1)
 289                goto out;
 290
 291        if (new_value) {
 292                length = selinux_disable();
 293                if (length)
 294                        goto out;
 295                audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
 296                        "selinux=0 auid=%u ses=%u",
 297                        from_kuid(&init_user_ns, audit_get_loginuid(current)),
 298                        audit_get_sessionid(current));
 299        }
 300
 301        length = count;
 302out:
 303        kfree(page);
 304        return length;
 305}
 306#else
 307#define sel_write_disable NULL
 308#endif
 309
 310static const struct file_operations sel_disable_ops = {
 311        .write          = sel_write_disable,
 312        .llseek         = generic_file_llseek,
 313};
 314
 315static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
 316                                   size_t count, loff_t *ppos)
 317{
 318        char tmpbuf[TMPBUFLEN];
 319        ssize_t length;
 320
 321        length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
 322        return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 323}
 324
 325static const struct file_operations sel_policyvers_ops = {
 326        .read           = sel_read_policyvers,
 327        .llseek         = generic_file_llseek,
 328};
 329
 330/* declaration for sel_write_load */
 331static int sel_make_bools(void);
 332static int sel_make_classes(void);
 333static int sel_make_policycap(void);
 334
 335/* declaration for sel_make_class_dirs */
 336static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
 337                        unsigned long *ino);
 338
 339static ssize_t sel_read_mls(struct file *filp, char __user *buf,
 340                                size_t count, loff_t *ppos)
 341{
 342        char tmpbuf[TMPBUFLEN];
 343        ssize_t length;
 344
 345        length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
 346                           security_mls_enabled());
 347        return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 348}
 349
 350static const struct file_operations sel_mls_ops = {
 351        .read           = sel_read_mls,
 352        .llseek         = generic_file_llseek,
 353};
 354
 355struct policy_load_memory {
 356        size_t len;
 357        void *data;
 358};
 359
 360static int sel_open_policy(struct inode *inode, struct file *filp)
 361{
 362        struct policy_load_memory *plm = NULL;
 363        int rc;
 364
 365        BUG_ON(filp->private_data);
 366
 367        mutex_lock(&sel_mutex);
 368
 369        rc = task_has_security(current, SECURITY__READ_POLICY);
 370        if (rc)
 371                goto err;
 372
 373        rc = -EBUSY;
 374        if (policy_opened)
 375                goto err;
 376
 377        rc = -ENOMEM;
 378        plm = kzalloc(sizeof(*plm), GFP_KERNEL);
 379        if (!plm)
 380                goto err;
 381
 382        if (i_size_read(inode) != security_policydb_len()) {
 383                inode_lock(inode);
 384                i_size_write(inode, security_policydb_len());
 385                inode_unlock(inode);
 386        }
 387
 388        rc = security_read_policy(&plm->data, &plm->len);
 389        if (rc)
 390                goto err;
 391
 392        policy_opened = 1;
 393
 394        filp->private_data = plm;
 395
 396        mutex_unlock(&sel_mutex);
 397
 398        return 0;
 399err:
 400        mutex_unlock(&sel_mutex);
 401
 402        if (plm)
 403                vfree(plm->data);
 404        kfree(plm);
 405        return rc;
 406}
 407
 408static int sel_release_policy(struct inode *inode, struct file *filp)
 409{
 410        struct policy_load_memory *plm = filp->private_data;
 411
 412        BUG_ON(!plm);
 413
 414        policy_opened = 0;
 415
 416        vfree(plm->data);
 417        kfree(plm);
 418
 419        return 0;
 420}
 421
 422static ssize_t sel_read_policy(struct file *filp, char __user *buf,
 423                               size_t count, loff_t *ppos)
 424{
 425        struct policy_load_memory *plm = filp->private_data;
 426        int ret;
 427
 428        mutex_lock(&sel_mutex);
 429
 430        ret = task_has_security(current, SECURITY__READ_POLICY);
 431        if (ret)
 432                goto out;
 433
 434        ret = simple_read_from_buffer(buf, count, ppos, plm->data, plm->len);
 435out:
 436        mutex_unlock(&sel_mutex);
 437        return ret;
 438}
 439
 440static int sel_mmap_policy_fault(struct vm_area_struct *vma,
 441                                 struct vm_fault *vmf)
 442{
 443        struct policy_load_memory *plm = vma->vm_file->private_data;
 444        unsigned long offset;
 445        struct page *page;
 446
 447        if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE))
 448                return VM_FAULT_SIGBUS;
 449
 450        offset = vmf->pgoff << PAGE_SHIFT;
 451        if (offset >= roundup(plm->len, PAGE_SIZE))
 452                return VM_FAULT_SIGBUS;
 453
 454        page = vmalloc_to_page(plm->data + offset);
 455        get_page(page);
 456
 457        vmf->page = page;
 458
 459        return 0;
 460}
 461
 462static const struct vm_operations_struct sel_mmap_policy_ops = {
 463        .fault = sel_mmap_policy_fault,
 464        .page_mkwrite = sel_mmap_policy_fault,
 465};
 466
 467static int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma)
 468{
 469        if (vma->vm_flags & VM_SHARED) {
 470                /* do not allow mprotect to make mapping writable */
 471                vma->vm_flags &= ~VM_MAYWRITE;
 472
 473                if (vma->vm_flags & VM_WRITE)
 474                        return -EACCES;
 475        }
 476
 477        vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
 478        vma->vm_ops = &sel_mmap_policy_ops;
 479
 480        return 0;
 481}
 482
 483static const struct file_operations sel_policy_ops = {
 484        .open           = sel_open_policy,
 485        .read           = sel_read_policy,
 486        .mmap           = sel_mmap_policy,
 487        .release        = sel_release_policy,
 488        .llseek         = generic_file_llseek,
 489};
 490
 491static ssize_t sel_write_load(struct file *file, const char __user *buf,
 492                              size_t count, loff_t *ppos)
 493
 494{
 495        ssize_t length;
 496        void *data = NULL;
 497
 498        mutex_lock(&sel_mutex);
 499
 500        length = task_has_security(current, SECURITY__LOAD_POLICY);
 501        if (length)
 502                goto out;
 503
 504        /* No partial writes. */
 505        length = -EINVAL;
 506        if (*ppos != 0)
 507                goto out;
 508
 509        length = -EFBIG;
 510        if (count > 64 * 1024 * 1024)
 511                goto out;
 512
 513        length = -ENOMEM;
 514        data = vmalloc(count);
 515        if (!data)
 516                goto out;
 517
 518        length = -EFAULT;
 519        if (copy_from_user(data, buf, count) != 0)
 520                goto out;
 521
 522        length = security_load_policy(data, count);
 523        if (length)
 524                goto out;
 525
 526        length = sel_make_bools();
 527        if (length)
 528                goto out1;
 529
 530        length = sel_make_classes();
 531        if (length)
 532                goto out1;
 533
 534        length = sel_make_policycap();
 535        if (length)
 536                goto out1;
 537
 538        length = count;
 539
 540out1:
 541        audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
 542                "policy loaded auid=%u ses=%u",
 543                from_kuid(&init_user_ns, audit_get_loginuid(current)),
 544                audit_get_sessionid(current));
 545out:
 546        mutex_unlock(&sel_mutex);
 547        vfree(data);
 548        return length;
 549}
 550
 551static const struct file_operations sel_load_ops = {
 552        .write          = sel_write_load,
 553        .llseek         = generic_file_llseek,
 554};
 555
 556static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
 557{
 558        char *canon = NULL;
 559        u32 sid, len;
 560        ssize_t length;
 561
 562        length = task_has_security(current, SECURITY__CHECK_CONTEXT);
 563        if (length)
 564                goto out;
 565
 566        length = security_context_to_sid(buf, size, &sid, GFP_KERNEL);
 567        if (length)
 568                goto out;
 569
 570        length = security_sid_to_context(sid, &canon, &len);
 571        if (length)
 572                goto out;
 573
 574        length = -ERANGE;
 575        if (len > SIMPLE_TRANSACTION_LIMIT) {
 576                printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
 577                        "payload max\n", __func__, len);
 578                goto out;
 579        }
 580
 581        memcpy(buf, canon, len);
 582        length = len;
 583out:
 584        kfree(canon);
 585        return length;
 586}
 587
 588static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
 589                                     size_t count, loff_t *ppos)
 590{
 591        char tmpbuf[TMPBUFLEN];
 592        ssize_t length;
 593
 594        length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot);
 595        return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 596}
 597
 598static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
 599                                      size_t count, loff_t *ppos)
 600{
 601        char *page;
 602        ssize_t length;
 603        unsigned int new_value;
 604
 605        length = task_has_security(current, SECURITY__SETCHECKREQPROT);
 606        if (length)
 607                return length;
 608
 609        if (count >= PAGE_SIZE)
 610                return -ENOMEM;
 611
 612        /* No partial writes. */
 613        if (*ppos != 0)
 614                return -EINVAL;
 615
 616        page = memdup_user_nul(buf, count);
 617        if (IS_ERR(page))
 618                return PTR_ERR(page);
 619
 620        length = -EINVAL;
 621        if (sscanf(page, "%u", &new_value) != 1)
 622                goto out;
 623
 624        selinux_checkreqprot = new_value ? 1 : 0;
 625        length = count;
 626out:
 627        kfree(page);
 628        return length;
 629}
 630static const struct file_operations sel_checkreqprot_ops = {
 631        .read           = sel_read_checkreqprot,
 632        .write          = sel_write_checkreqprot,
 633        .llseek         = generic_file_llseek,
 634};
 635
 636static ssize_t sel_write_validatetrans(struct file *file,
 637                                        const char __user *buf,
 638                                        size_t count, loff_t *ppos)
 639{
 640        char *oldcon = NULL, *newcon = NULL, *taskcon = NULL;
 641        char *req = NULL;
 642        u32 osid, nsid, tsid;
 643        u16 tclass;
 644        int rc;
 645
 646        rc = task_has_security(current, SECURITY__VALIDATE_TRANS);
 647        if (rc)
 648                goto out;
 649
 650        rc = -ENOMEM;
 651        if (count >= PAGE_SIZE)
 652                goto out;
 653
 654        /* No partial writes. */
 655        rc = -EINVAL;
 656        if (*ppos != 0)
 657                goto out;
 658
 659        rc = -ENOMEM;
 660        req = kzalloc(count + 1, GFP_KERNEL);
 661        if (!req)
 662                goto out;
 663
 664        rc = -EFAULT;
 665        if (copy_from_user(req, buf, count))
 666                goto out;
 667
 668        rc = -ENOMEM;
 669        oldcon = kzalloc(count + 1, GFP_KERNEL);
 670        if (!oldcon)
 671                goto out;
 672
 673        newcon = kzalloc(count + 1, GFP_KERNEL);
 674        if (!newcon)
 675                goto out;
 676
 677        taskcon = kzalloc(count + 1, GFP_KERNEL);
 678        if (!taskcon)
 679                goto out;
 680
 681        rc = -EINVAL;
 682        if (sscanf(req, "%s %s %hu %s", oldcon, newcon, &tclass, taskcon) != 4)
 683                goto out;
 684
 685        rc = security_context_str_to_sid(oldcon, &osid, GFP_KERNEL);
 686        if (rc)
 687                goto out;
 688
 689        rc = security_context_str_to_sid(newcon, &nsid, GFP_KERNEL);
 690        if (rc)
 691                goto out;
 692
 693        rc = security_context_str_to_sid(taskcon, &tsid, GFP_KERNEL);
 694        if (rc)
 695                goto out;
 696
 697        rc = security_validate_transition_user(osid, nsid, tsid, tclass);
 698        if (!rc)
 699                rc = count;
 700out:
 701        kfree(req);
 702        kfree(oldcon);
 703        kfree(newcon);
 704        kfree(taskcon);
 705        return rc;
 706}
 707
 708static const struct file_operations sel_transition_ops = {
 709        .write          = sel_write_validatetrans,
 710        .llseek         = generic_file_llseek,
 711};
 712
 713/*
 714 * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
 715 */
 716static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
 717static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
 718static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
 719static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
 720static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
 721
 722static ssize_t (*write_op[])(struct file *, char *, size_t) = {
 723        [SEL_ACCESS] = sel_write_access,
 724        [SEL_CREATE] = sel_write_create,
 725        [SEL_RELABEL] = sel_write_relabel,
 726        [SEL_USER] = sel_write_user,
 727        [SEL_MEMBER] = sel_write_member,
 728        [SEL_CONTEXT] = sel_write_context,
 729};
 730
 731static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
 732{
 733        ino_t ino = file_inode(file)->i_ino;
 734        char *data;
 735        ssize_t rv;
 736
 737        if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
 738                return -EINVAL;
 739
 740        data = simple_transaction_get(file, buf, size);
 741        if (IS_ERR(data))
 742                return PTR_ERR(data);
 743
 744        rv = write_op[ino](file, data, size);
 745        if (rv > 0) {
 746                simple_transaction_set(file, rv);
 747                rv = size;
 748        }
 749        return rv;
 750}
 751
 752static const struct file_operations transaction_ops = {
 753        .write          = selinux_transaction_write,
 754        .read           = simple_transaction_read,
 755        .release        = simple_transaction_release,
 756        .llseek         = generic_file_llseek,
 757};
 758
 759/*
 760 * payload - write methods
 761 * If the method has a response, the response should be put in buf,
 762 * and the length returned.  Otherwise return 0 or and -error.
 763 */
 764
 765static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
 766{
 767        char *scon = NULL, *tcon = NULL;
 768        u32 ssid, tsid;
 769        u16 tclass;
 770        struct av_decision avd;
 771        ssize_t length;
 772
 773        length = task_has_security(current, SECURITY__COMPUTE_AV);
 774        if (length)
 775                goto out;
 776
 777        length = -ENOMEM;
 778        scon = kzalloc(size + 1, GFP_KERNEL);
 779        if (!scon)
 780                goto out;
 781
 782        length = -ENOMEM;
 783        tcon = kzalloc(size + 1, GFP_KERNEL);
 784        if (!tcon)
 785                goto out;
 786
 787        length = -EINVAL;
 788        if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 789                goto out;
 790
 791        length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
 792        if (length)
 793                goto out;
 794
 795        length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
 796        if (length)
 797                goto out;
 798
 799        security_compute_av_user(ssid, tsid, tclass, &avd);
 800
 801        length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
 802                          "%x %x %x %x %u %x",
 803                          avd.allowed, 0xffffffff,
 804                          avd.auditallow, avd.auditdeny,
 805                          avd.seqno, avd.flags);
 806out:
 807        kfree(tcon);
 808        kfree(scon);
 809        return length;
 810}
 811
 812static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
 813{
 814        char *scon = NULL, *tcon = NULL;
 815        char *namebuf = NULL, *objname = NULL;
 816        u32 ssid, tsid, newsid;
 817        u16 tclass;
 818        ssize_t length;
 819        char *newcon = NULL;
 820        u32 len;
 821        int nargs;
 822
 823        length = task_has_security(current, SECURITY__COMPUTE_CREATE);
 824        if (length)
 825                goto out;
 826
 827        length = -ENOMEM;
 828        scon = kzalloc(size + 1, GFP_KERNEL);
 829        if (!scon)
 830                goto out;
 831
 832        length = -ENOMEM;
 833        tcon = kzalloc(size + 1, GFP_KERNEL);
 834        if (!tcon)
 835                goto out;
 836
 837        length = -ENOMEM;
 838        namebuf = kzalloc(size + 1, GFP_KERNEL);
 839        if (!namebuf)
 840                goto out;
 841
 842        length = -EINVAL;
 843        nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf);
 844        if (nargs < 3 || nargs > 4)
 845                goto out;
 846        if (nargs == 4) {
 847                /*
 848                 * If and when the name of new object to be queried contains
 849                 * either whitespace or multibyte characters, they shall be
 850                 * encoded based on the percentage-encoding rule.
 851                 * If not encoded, the sscanf logic picks up only left-half
 852                 * of the supplied name; splitted by a whitespace unexpectedly.
 853                 */
 854                char   *r, *w;
 855                int     c1, c2;
 856
 857                r = w = namebuf;
 858                do {
 859                        c1 = *r++;
 860                        if (c1 == '+')
 861                                c1 = ' ';
 862                        else if (c1 == '%') {
 863                                c1 = hex_to_bin(*r++);
 864                                if (c1 < 0)
 865                                        goto out;
 866                                c2 = hex_to_bin(*r++);
 867                                if (c2 < 0)
 868                                        goto out;
 869                                c1 = (c1 << 4) | c2;
 870                        }
 871                        *w++ = c1;
 872                } while (c1 != '\0');
 873
 874                objname = namebuf;
 875        }
 876
 877        length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
 878        if (length)
 879                goto out;
 880
 881        length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
 882        if (length)
 883                goto out;
 884
 885        length = security_transition_sid_user(ssid, tsid, tclass,
 886                                              objname, &newsid);
 887        if (length)
 888                goto out;
 889
 890        length = security_sid_to_context(newsid, &newcon, &len);
 891        if (length)
 892                goto out;
 893
 894        length = -ERANGE;
 895        if (len > SIMPLE_TRANSACTION_LIMIT) {
 896                printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
 897                        "payload max\n", __func__, len);
 898                goto out;
 899        }
 900
 901        memcpy(buf, newcon, len);
 902        length = len;
 903out:
 904        kfree(newcon);
 905        kfree(namebuf);
 906        kfree(tcon);
 907        kfree(scon);
 908        return length;
 909}
 910
 911static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
 912{
 913        char *scon = NULL, *tcon = NULL;
 914        u32 ssid, tsid, newsid;
 915        u16 tclass;
 916        ssize_t length;
 917        char *newcon = NULL;
 918        u32 len;
 919
 920        length = task_has_security(current, SECURITY__COMPUTE_RELABEL);
 921        if (length)
 922                goto out;
 923
 924        length = -ENOMEM;
 925        scon = kzalloc(size + 1, GFP_KERNEL);
 926        if (!scon)
 927                goto out;
 928
 929        length = -ENOMEM;
 930        tcon = kzalloc(size + 1, GFP_KERNEL);
 931        if (!tcon)
 932                goto out;
 933
 934        length = -EINVAL;
 935        if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 936                goto out;
 937
 938        length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
 939        if (length)
 940                goto out;
 941
 942        length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
 943        if (length)
 944                goto out;
 945
 946        length = security_change_sid(ssid, tsid, tclass, &newsid);
 947        if (length)
 948                goto out;
 949
 950        length = security_sid_to_context(newsid, &newcon, &len);
 951        if (length)
 952                goto out;
 953
 954        length = -ERANGE;
 955        if (len > SIMPLE_TRANSACTION_LIMIT)
 956                goto out;
 957
 958        memcpy(buf, newcon, len);
 959        length = len;
 960out:
 961        kfree(newcon);
 962        kfree(tcon);
 963        kfree(scon);
 964        return length;
 965}
 966
 967static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
 968{
 969        char *con = NULL, *user = NULL, *ptr;
 970        u32 sid, *sids = NULL;
 971        ssize_t length;
 972        char *newcon;
 973        int i, rc;
 974        u32 len, nsids;
 975
 976        length = task_has_security(current, SECURITY__COMPUTE_USER);
 977        if (length)
 978                goto out;
 979
 980        length = -ENOMEM;
 981        con = kzalloc(size + 1, GFP_KERNEL);
 982        if (!con)
 983                goto out;
 984
 985        length = -ENOMEM;
 986        user = kzalloc(size + 1, GFP_KERNEL);
 987        if (!user)
 988                goto out;
 989
 990        length = -EINVAL;
 991        if (sscanf(buf, "%s %s", con, user) != 2)
 992                goto out;
 993
 994        length = security_context_str_to_sid(con, &sid, GFP_KERNEL);
 995        if (length)
 996                goto out;
 997
 998        length = security_get_user_sids(sid, user, &sids, &nsids);
 999        if (length)
1000                goto out;
1001
1002        length = sprintf(buf, "%u", nsids) + 1;
1003        ptr = buf + length;
1004        for (i = 0; i < nsids; i++) {
1005                rc = security_sid_to_context(sids[i], &newcon, &len);
1006                if (rc) {
1007                        length = rc;
1008                        goto out;
1009                }
1010                if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
1011                        kfree(newcon);
1012                        length = -ERANGE;
1013                        goto out;
1014                }
1015                memcpy(ptr, newcon, len);
1016                kfree(newcon);
1017                ptr += len;
1018                length += len;
1019        }
1020out:
1021        kfree(sids);
1022        kfree(user);
1023        kfree(con);
1024        return length;
1025}
1026
1027static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
1028{
1029        char *scon = NULL, *tcon = NULL;
1030        u32 ssid, tsid, newsid;
1031        u16 tclass;
1032        ssize_t length;
1033        char *newcon = NULL;
1034        u32 len;
1035
1036        length = task_has_security(current, SECURITY__COMPUTE_MEMBER);
1037        if (length)
1038                goto out;
1039
1040        length = -ENOMEM;
1041        scon = kzalloc(size + 1, GFP_KERNEL);
1042        if (!scon)
1043                goto out;
1044
1045        length = -ENOMEM;
1046        tcon = kzalloc(size + 1, GFP_KERNEL);
1047        if (!tcon)
1048                goto out;
1049
1050        length = -EINVAL;
1051        if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
1052                goto out;
1053
1054        length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
1055        if (length)
1056                goto out;
1057
1058        length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
1059        if (length)
1060                goto out;
1061
1062        length = security_member_sid(ssid, tsid, tclass, &newsid);
1063        if (length)
1064                goto out;
1065
1066        length = security_sid_to_context(newsid, &newcon, &len);
1067        if (length)
1068                goto out;
1069
1070        length = -ERANGE;
1071        if (len > SIMPLE_TRANSACTION_LIMIT) {
1072                printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
1073                        "payload max\n", __func__, len);
1074                goto out;
1075        }
1076
1077        memcpy(buf, newcon, len);
1078        length = len;
1079out:
1080        kfree(newcon);
1081        kfree(tcon);
1082        kfree(scon);
1083        return length;
1084}
1085
1086static struct inode *sel_make_inode(struct super_block *sb, int mode)
1087{
1088        struct inode *ret = new_inode(sb);
1089
1090        if (ret) {
1091                ret->i_mode = mode;
1092                ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
1093        }
1094        return ret;
1095}
1096
1097static ssize_t sel_read_bool(struct file *filep, char __user *buf,
1098                             size_t count, loff_t *ppos)
1099{
1100        char *page = NULL;
1101        ssize_t length;
1102        ssize_t ret;
1103        int cur_enforcing;
1104        unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
1105        const char *name = filep->f_path.dentry->d_name.name;
1106
1107        mutex_lock(&sel_mutex);
1108
1109        ret = -EINVAL;
1110        if (index >= bool_num || strcmp(name, bool_pending_names[index]))
1111                goto out;
1112
1113        ret = -ENOMEM;
1114        page = (char *)get_zeroed_page(GFP_KERNEL);
1115        if (!page)
1116                goto out;
1117
1118        cur_enforcing = security_get_bool_value(index);
1119        if (cur_enforcing < 0) {
1120                ret = cur_enforcing;
1121                goto out;
1122        }
1123        length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
1124                          bool_pending_values[index]);
1125        ret = simple_read_from_buffer(buf, count, ppos, page, length);
1126out:
1127        mutex_unlock(&sel_mutex);
1128        free_page((unsigned long)page);
1129        return ret;
1130}
1131
1132static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
1133                              size_t count, loff_t *ppos)
1134{
1135        char *page = NULL;
1136        ssize_t length;
1137        int new_value;
1138        unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
1139        const char *name = filep->f_path.dentry->d_name.name;
1140
1141        mutex_lock(&sel_mutex);
1142
1143        length = task_has_security(current, SECURITY__SETBOOL);
1144        if (length)
1145                goto out;
1146
1147        length = -EINVAL;
1148        if (index >= bool_num || strcmp(name, bool_pending_names[index]))
1149                goto out;
1150
1151        length = -ENOMEM;
1152        if (count >= PAGE_SIZE)
1153                goto out;
1154
1155        /* No partial writes. */
1156        length = -EINVAL;
1157        if (*ppos != 0)
1158                goto out;
1159
1160        page = memdup_user_nul(buf, count);
1161        if (IS_ERR(page)) {
1162                length = PTR_ERR(page);
1163                page = NULL;
1164                goto out;
1165        }
1166
1167        length = -EINVAL;
1168        if (sscanf(page, "%d", &new_value) != 1)
1169                goto out;
1170
1171        if (new_value)
1172                new_value = 1;
1173
1174        bool_pending_values[index] = new_value;
1175        length = count;
1176
1177out:
1178        mutex_unlock(&sel_mutex);
1179        kfree(page);
1180        return length;
1181}
1182
1183static const struct file_operations sel_bool_ops = {
1184        .read           = sel_read_bool,
1185        .write          = sel_write_bool,
1186        .llseek         = generic_file_llseek,
1187};
1188
1189static ssize_t sel_commit_bools_write(struct file *filep,
1190                                      const char __user *buf,
1191                                      size_t count, loff_t *ppos)
1192{
1193        char *page = NULL;
1194        ssize_t length;
1195        int new_value;
1196
1197        mutex_lock(&sel_mutex);
1198
1199        length = task_has_security(current, SECURITY__SETBOOL);
1200        if (length)
1201                goto out;
1202
1203        length = -ENOMEM;
1204        if (count >= PAGE_SIZE)
1205                goto out;
1206
1207        /* No partial writes. */
1208        length = -EINVAL;
1209        if (*ppos != 0)
1210                goto out;
1211
1212        page = memdup_user_nul(buf, count);
1213        if (IS_ERR(page)) {
1214                length = PTR_ERR(page);
1215                page = NULL;
1216                goto out;
1217        }
1218
1219        length = -EINVAL;
1220        if (sscanf(page, "%d", &new_value) != 1)
1221                goto out;
1222
1223        length = 0;
1224        if (new_value && bool_pending_values)
1225                length = security_set_bools(bool_num, bool_pending_values);
1226
1227        if (!length)
1228                length = count;
1229
1230out:
1231        mutex_unlock(&sel_mutex);
1232        kfree(page);
1233        return length;
1234}
1235
1236static const struct file_operations sel_commit_bools_ops = {
1237        .write          = sel_commit_bools_write,
1238        .llseek         = generic_file_llseek,
1239};
1240
1241static void sel_remove_entries(struct dentry *de)
1242{
1243        d_genocide(de);
1244        shrink_dcache_parent(de);
1245}
1246
1247#define BOOL_DIR_NAME "booleans"
1248
1249static int sel_make_bools(void)
1250{
1251        int i, ret;
1252        ssize_t len;
1253        struct dentry *dentry = NULL;
1254        struct dentry *dir = bool_dir;
1255        struct inode *inode = NULL;
1256        struct inode_security_struct *isec;
1257        char **names = NULL, *page;
1258        int num;
1259        int *values = NULL;
1260        u32 sid;
1261
1262        /* remove any existing files */
1263        for (i = 0; i < bool_num; i++)
1264                kfree(bool_pending_names[i]);
1265        kfree(bool_pending_names);
1266        kfree(bool_pending_values);
1267        bool_num = 0;
1268        bool_pending_names = NULL;
1269        bool_pending_values = NULL;
1270
1271        sel_remove_entries(dir);
1272
1273        ret = -ENOMEM;
1274        page = (char *)get_zeroed_page(GFP_KERNEL);
1275        if (!page)
1276                goto out;
1277
1278        ret = security_get_bools(&num, &names, &values);
1279        if (ret)
1280                goto out;
1281
1282        for (i = 0; i < num; i++) {
1283                ret = -ENOMEM;
1284                dentry = d_alloc_name(dir, names[i]);
1285                if (!dentry)
1286                        goto out;
1287
1288                ret = -ENOMEM;
1289                inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1290                if (!inode)
1291                        goto out;
1292
1293                ret = -ENAMETOOLONG;
1294                len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1295                if (len >= PAGE_SIZE)
1296                        goto out;
1297
1298                isec = (struct inode_security_struct *)inode->i_security;
1299                ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid);
1300                if (ret)
1301                        goto out;
1302
1303                isec->sid = sid;
1304                isec->initialized = 1;
1305                inode->i_fop = &sel_bool_ops;
1306                inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1307                d_add(dentry, inode);
1308        }
1309        bool_num = num;
1310        bool_pending_names = names;
1311        bool_pending_values = values;
1312
1313        free_page((unsigned long)page);
1314        return 0;
1315out:
1316        free_page((unsigned long)page);
1317
1318        if (names) {
1319                for (i = 0; i < num; i++)
1320                        kfree(names[i]);
1321                kfree(names);
1322        }
1323        kfree(values);
1324        sel_remove_entries(dir);
1325
1326        return ret;
1327}
1328
1329#define NULL_FILE_NAME "null"
1330
1331struct path selinux_null;
1332
1333static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1334                                            size_t count, loff_t *ppos)
1335{
1336        char tmpbuf[TMPBUFLEN];
1337        ssize_t length;
1338
1339        length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
1340        return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1341}
1342
1343static ssize_t sel_write_avc_cache_threshold(struct file *file,
1344                                             const char __user *buf,
1345                                             size_t count, loff_t *ppos)
1346
1347{
1348        char *page;
1349        ssize_t ret;
1350        int new_value;
1351
1352        ret = task_has_security(current, SECURITY__SETSECPARAM);
1353        if (ret)
1354                return ret;
1355
1356        if (count >= PAGE_SIZE)
1357                return -ENOMEM;
1358
1359        /* No partial writes. */
1360        if (*ppos != 0)
1361                return -EINVAL;
1362
1363        page = memdup_user_nul(buf, count);
1364        if (IS_ERR(page))
1365                return PTR_ERR(page);
1366
1367        ret = -EINVAL;
1368        if (sscanf(page, "%u", &new_value) != 1)
1369                goto out;
1370
1371        avc_cache_threshold = new_value;
1372
1373        ret = count;
1374out:
1375        kfree(page);
1376        return ret;
1377}
1378
1379static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1380                                       size_t count, loff_t *ppos)
1381{
1382        char *page;
1383        ssize_t length;
1384
1385        page = (char *)__get_free_page(GFP_KERNEL);
1386        if (!page)
1387                return -ENOMEM;
1388
1389        length = avc_get_hash_stats(page);
1390        if (length >= 0)
1391                length = simple_read_from_buffer(buf, count, ppos, page, length);
1392        free_page((unsigned long)page);
1393
1394        return length;
1395}
1396
1397static const struct file_operations sel_avc_cache_threshold_ops = {
1398        .read           = sel_read_avc_cache_threshold,
1399        .write          = sel_write_avc_cache_threshold,
1400        .llseek         = generic_file_llseek,
1401};
1402
1403static const struct file_operations sel_avc_hash_stats_ops = {
1404        .read           = sel_read_avc_hash_stats,
1405        .llseek         = generic_file_llseek,
1406};
1407
1408#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1409static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1410{
1411        int cpu;
1412
1413        for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
1414                if (!cpu_possible(cpu))
1415                        continue;
1416                *idx = cpu + 1;
1417                return &per_cpu(avc_cache_stats, cpu);
1418        }
1419        return NULL;
1420}
1421
1422static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1423{
1424        loff_t n = *pos - 1;
1425
1426        if (*pos == 0)
1427                return SEQ_START_TOKEN;
1428
1429        return sel_avc_get_stat_idx(&n);
1430}
1431
1432static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1433{
1434        return sel_avc_get_stat_idx(pos);
1435}
1436
1437static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1438{
1439        struct avc_cache_stats *st = v;
1440
1441        if (v == SEQ_START_TOKEN)
1442                seq_printf(seq, "lookups hits misses allocations reclaims "
1443                           "frees\n");
1444        else {
1445                unsigned int lookups = st->lookups;
1446                unsigned int misses = st->misses;
1447                unsigned int hits = lookups - misses;
1448                seq_printf(seq, "%u %u %u %u %u %u\n", lookups,
1449                           hits, misses, st->allocations,
1450                           st->reclaims, st->frees);
1451        }
1452        return 0;
1453}
1454
1455static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1456{ }
1457
1458static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1459        .start          = sel_avc_stats_seq_start,
1460        .next           = sel_avc_stats_seq_next,
1461        .show           = sel_avc_stats_seq_show,
1462        .stop           = sel_avc_stats_seq_stop,
1463};
1464
1465static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1466{
1467        return seq_open(file, &sel_avc_cache_stats_seq_ops);
1468}
1469
1470static const struct file_operations sel_avc_cache_stats_ops = {
1471        .open           = sel_open_avc_cache_stats,
1472        .read           = seq_read,
1473        .llseek         = seq_lseek,
1474        .release        = seq_release,
1475};
1476#endif
1477
1478static int sel_make_avc_files(struct dentry *dir)
1479{
1480        int i;
1481        static struct tree_descr files[] = {
1482                { "cache_threshold",
1483                  &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1484                { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1485#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1486                { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1487#endif
1488        };
1489
1490        for (i = 0; i < ARRAY_SIZE(files); i++) {
1491                struct inode *inode;
1492                struct dentry *dentry;
1493
1494                dentry = d_alloc_name(dir, files[i].name);
1495                if (!dentry)
1496                        return -ENOMEM;
1497
1498                inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1499                if (!inode)
1500                        return -ENOMEM;
1501
1502                inode->i_fop = files[i].ops;
1503                inode->i_ino = ++sel_last_ino;
1504                d_add(dentry, inode);
1505        }
1506
1507        return 0;
1508}
1509
1510static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1511                                size_t count, loff_t *ppos)
1512{
1513        char *con;
1514        u32 sid, len;
1515        ssize_t ret;
1516
1517        sid = file_inode(file)->i_ino&SEL_INO_MASK;
1518        ret = security_sid_to_context(sid, &con, &len);
1519        if (ret)
1520                return ret;
1521
1522        ret = simple_read_from_buffer(buf, count, ppos, con, len);
1523        kfree(con);
1524        return ret;
1525}
1526
1527static const struct file_operations sel_initcon_ops = {
1528        .read           = sel_read_initcon,
1529        .llseek         = generic_file_llseek,
1530};
1531
1532static int sel_make_initcon_files(struct dentry *dir)
1533{
1534        int i;
1535
1536        for (i = 1; i <= SECINITSID_NUM; i++) {
1537                struct inode *inode;
1538                struct dentry *dentry;
1539                dentry = d_alloc_name(dir, security_get_initial_sid_context(i));
1540                if (!dentry)
1541                        return -ENOMEM;
1542
1543                inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1544                if (!inode)
1545                        return -ENOMEM;
1546
1547                inode->i_fop = &sel_initcon_ops;
1548                inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1549                d_add(dentry, inode);
1550        }
1551
1552        return 0;
1553}
1554
1555static inline unsigned long sel_class_to_ino(u16 class)
1556{
1557        return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1558}
1559
1560static inline u16 sel_ino_to_class(unsigned long ino)
1561{
1562        return (ino & SEL_INO_MASK) / (SEL_VEC_MAX + 1);
1563}
1564
1565static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1566{
1567        return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1568}
1569
1570static inline u32 sel_ino_to_perm(unsigned long ino)
1571{
1572        return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1573}
1574
1575static ssize_t sel_read_class(struct file *file, char __user *buf,
1576                                size_t count, loff_t *ppos)
1577{
1578        unsigned long ino = file_inode(file)->i_ino;
1579        char res[TMPBUFLEN];
1580        ssize_t len = snprintf(res, sizeof(res), "%d", sel_ino_to_class(ino));
1581        return simple_read_from_buffer(buf, count, ppos, res, len);
1582}
1583
1584static const struct file_operations sel_class_ops = {
1585        .read           = sel_read_class,
1586        .llseek         = generic_file_llseek,
1587};
1588
1589static ssize_t sel_read_perm(struct file *file, char __user *buf,
1590                                size_t count, loff_t *ppos)
1591{
1592        unsigned long ino = file_inode(file)->i_ino;
1593        char res[TMPBUFLEN];
1594        ssize_t len = snprintf(res, sizeof(res), "%d", sel_ino_to_perm(ino));
1595        return simple_read_from_buffer(buf, count, ppos, res, len);
1596}
1597
1598static const struct file_operations sel_perm_ops = {
1599        .read           = sel_read_perm,
1600        .llseek         = generic_file_llseek,
1601};
1602
1603static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1604                                  size_t count, loff_t *ppos)
1605{
1606        int value;
1607        char tmpbuf[TMPBUFLEN];
1608        ssize_t length;
1609        unsigned long i_ino = file_inode(file)->i_ino;
1610
1611        value = security_policycap_supported(i_ino & SEL_INO_MASK);
1612        length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
1613
1614        return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1615}
1616
1617static const struct file_operations sel_policycap_ops = {
1618        .read           = sel_read_policycap,
1619        .llseek         = generic_file_llseek,
1620};
1621
1622static int sel_make_perm_files(char *objclass, int classvalue,
1623                                struct dentry *dir)
1624{
1625        int i, rc, nperms;
1626        char **perms;
1627
1628        rc = security_get_permissions(objclass, &perms, &nperms);
1629        if (rc)
1630                return rc;
1631
1632        for (i = 0; i < nperms; i++) {
1633                struct inode *inode;
1634                struct dentry *dentry;
1635
1636                rc = -ENOMEM;
1637                dentry = d_alloc_name(dir, perms[i]);
1638                if (!dentry)
1639                        goto out;
1640
1641                rc = -ENOMEM;
1642                inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1643                if (!inode)
1644                        goto out;
1645
1646                inode->i_fop = &sel_perm_ops;
1647                /* i+1 since perm values are 1-indexed */
1648                inode->i_ino = sel_perm_to_ino(classvalue, i + 1);
1649                d_add(dentry, inode);
1650        }
1651        rc = 0;
1652out:
1653        for (i = 0; i < nperms; i++)
1654                kfree(perms[i]);
1655        kfree(perms);
1656        return rc;
1657}
1658
1659static int sel_make_class_dir_entries(char *classname, int index,
1660                                        struct dentry *dir)
1661{
1662        struct dentry *dentry = NULL;
1663        struct inode *inode = NULL;
1664        int rc;
1665
1666        dentry = d_alloc_name(dir, "index");
1667        if (!dentry)
1668                return -ENOMEM;
1669
1670        inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1671        if (!inode)
1672                return -ENOMEM;
1673
1674        inode->i_fop = &sel_class_ops;
1675        inode->i_ino = sel_class_to_ino(index);
1676        d_add(dentry, inode);
1677
1678        dentry = sel_make_dir(dir, "perms", &last_class_ino);
1679        if (IS_ERR(dentry))
1680                return PTR_ERR(dentry);
1681
1682        rc = sel_make_perm_files(classname, index, dentry);
1683
1684        return rc;
1685}
1686
1687static int sel_make_classes(void)
1688{
1689        int rc, nclasses, i;
1690        char **classes;
1691
1692        /* delete any existing entries */
1693        sel_remove_entries(class_dir);
1694
1695        rc = security_get_classes(&classes, &nclasses);
1696        if (rc)
1697                return rc;
1698
1699        /* +2 since classes are 1-indexed */
1700        last_class_ino = sel_class_to_ino(nclasses + 2);
1701
1702        for (i = 0; i < nclasses; i++) {
1703                struct dentry *class_name_dir;
1704
1705                class_name_dir = sel_make_dir(class_dir, classes[i],
1706                                &last_class_ino);
1707                if (IS_ERR(class_name_dir)) {
1708                        rc = PTR_ERR(class_name_dir);
1709                        goto out;
1710                }
1711
1712                /* i+1 since class values are 1-indexed */
1713                rc = sel_make_class_dir_entries(classes[i], i + 1,
1714                                class_name_dir);
1715                if (rc)
1716                        goto out;
1717        }
1718        rc = 0;
1719out:
1720        for (i = 0; i < nclasses; i++)
1721                kfree(classes[i]);
1722        kfree(classes);
1723        return rc;
1724}
1725
1726static int sel_make_policycap(void)
1727{
1728        unsigned int iter;
1729        struct dentry *dentry = NULL;
1730        struct inode *inode = NULL;
1731
1732        sel_remove_entries(policycap_dir);
1733
1734        for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) {
1735                if (iter < ARRAY_SIZE(policycap_names))
1736                        dentry = d_alloc_name(policycap_dir,
1737                                              policycap_names[iter]);
1738                else
1739                        dentry = d_alloc_name(policycap_dir, "unknown");
1740
1741                if (dentry == NULL)
1742                        return -ENOMEM;
1743
1744                inode = sel_make_inode(policycap_dir->d_sb, S_IFREG | S_IRUGO);
1745                if (inode == NULL)
1746                        return -ENOMEM;
1747
1748                inode->i_fop = &sel_policycap_ops;
1749                inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
1750                d_add(dentry, inode);
1751        }
1752
1753        return 0;
1754}
1755
1756static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
1757                        unsigned long *ino)
1758{
1759        struct dentry *dentry = d_alloc_name(dir, name);
1760        struct inode *inode;
1761
1762        if (!dentry)
1763                return ERR_PTR(-ENOMEM);
1764
1765        inode = sel_make_inode(dir->d_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1766        if (!inode) {
1767                dput(dentry);
1768                return ERR_PTR(-ENOMEM);
1769        }
1770
1771        inode->i_op = &simple_dir_inode_operations;
1772        inode->i_fop = &simple_dir_operations;
1773        inode->i_ino = ++(*ino);
1774        /* directory inodes start off with i_nlink == 2 (for "." entry) */
1775        inc_nlink(inode);
1776        d_add(dentry, inode);
1777        /* bump link count on parent directory, too */
1778        inc_nlink(d_inode(dir));
1779
1780        return dentry;
1781}
1782
1783static int sel_fill_super(struct super_block *sb, void *data, int silent)
1784{
1785        int ret;
1786        struct dentry *dentry;
1787        struct inode *inode;
1788        struct inode_security_struct *isec;
1789
1790        static struct tree_descr selinux_files[] = {
1791                [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1792                [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1793                [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1794                [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1795                [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1796                [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1797                [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1798                [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1799                [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1800                [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1801                [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1802                [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1803                [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1804                [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
1805                [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
1806                [SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO},
1807                [SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUGO},
1808                [SEL_VALIDATE_TRANS] = {"validatetrans", &sel_transition_ops,
1809                                        S_IWUGO},
1810                /* last one */ {""}
1811        };
1812        ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1813        if (ret)
1814                goto err;
1815
1816        bool_dir = sel_make_dir(sb->s_root, BOOL_DIR_NAME, &sel_last_ino);
1817        if (IS_ERR(bool_dir)) {
1818                ret = PTR_ERR(bool_dir);
1819                bool_dir = NULL;
1820                goto err;
1821        }
1822
1823        ret = -ENOMEM;
1824        dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1825        if (!dentry)
1826                goto err;
1827
1828        ret = -ENOMEM;
1829        inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1830        if (!inode)
1831                goto err;
1832
1833        inode->i_ino = ++sel_last_ino;
1834        isec = (struct inode_security_struct *)inode->i_security;
1835        isec->sid = SECINITSID_DEVNULL;
1836        isec->sclass = SECCLASS_CHR_FILE;
1837        isec->initialized = 1;
1838
1839        init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1840        d_add(dentry, inode);
1841        selinux_null.dentry = dentry;
1842
1843        dentry = sel_make_dir(sb->s_root, "avc", &sel_last_ino);
1844        if (IS_ERR(dentry)) {
1845                ret = PTR_ERR(dentry);
1846                goto err;
1847        }
1848
1849        ret = sel_make_avc_files(dentry);
1850        if (ret)
1851                goto err;
1852
1853        dentry = sel_make_dir(sb->s_root, "initial_contexts", &sel_last_ino);
1854        if (IS_ERR(dentry)) {
1855                ret = PTR_ERR(dentry);
1856                goto err;
1857        }
1858
1859        ret = sel_make_initcon_files(dentry);
1860        if (ret)
1861                goto err;
1862
1863        class_dir = sel_make_dir(sb->s_root, "class", &sel_last_ino);
1864        if (IS_ERR(class_dir)) {
1865                ret = PTR_ERR(class_dir);
1866                class_dir = NULL;
1867                goto err;
1868        }
1869
1870        policycap_dir = sel_make_dir(sb->s_root, "policy_capabilities", &sel_last_ino);
1871        if (IS_ERR(policycap_dir)) {
1872                ret = PTR_ERR(policycap_dir);
1873                policycap_dir = NULL;
1874                goto err;
1875        }
1876        return 0;
1877err:
1878        printk(KERN_ERR "SELinux: %s:  failed while creating inodes\n",
1879                __func__);
1880        return ret;
1881}
1882
1883static struct dentry *sel_mount(struct file_system_type *fs_type,
1884                      int flags, const char *dev_name, void *data)
1885{
1886        return mount_single(fs_type, flags, data, sel_fill_super);
1887}
1888
1889static struct file_system_type sel_fs_type = {
1890        .name           = "selinuxfs",
1891        .mount          = sel_mount,
1892        .kill_sb        = kill_litter_super,
1893};
1894
1895struct vfsmount *selinuxfs_mount;
1896
1897static int __init init_sel_fs(void)
1898{
1899        int err;
1900
1901        if (!selinux_enabled)
1902                return 0;
1903
1904        err = sysfs_create_mount_point(fs_kobj, "selinux");
1905        if (err)
1906                return err;
1907
1908        err = register_filesystem(&sel_fs_type);
1909        if (err) {
1910                sysfs_remove_mount_point(fs_kobj, "selinux");
1911                return err;
1912        }
1913
1914        selinux_null.mnt = selinuxfs_mount = kern_mount(&sel_fs_type);
1915        if (IS_ERR(selinuxfs_mount)) {
1916                printk(KERN_ERR "selinuxfs:  could not mount!\n");
1917                err = PTR_ERR(selinuxfs_mount);
1918                selinuxfs_mount = NULL;
1919        }
1920
1921        return err;
1922}
1923
1924__initcall(init_sel_fs);
1925
1926#ifdef CONFIG_SECURITY_SELINUX_DISABLE
1927void exit_sel_fs(void)
1928{
1929        sysfs_remove_mount_point(fs_kobj, "selinux");
1930        kern_unmount(selinuxfs_mount);
1931        unregister_filesystem(&sel_fs_type);
1932}
1933#endif
1934