security/tomoyo/common.c

   1 /*
   2  * security/tomoyo/common.c
   3  *
   4  * Common functions for TOMOYO.
   5  *
   6  * Copyright (C) 2005-2010  NTT DATA CORPORATION
   7  */
   8
   9 #include <linux/uaccess.h>
  10 #include <linux/slab.h>
  11 #include <linux/security.h>
  12 #include "common.h"
  13
  14 static struct tomoyo_profile tomoyo_default_profile = {
  15         .learning = &tomoyo_default_profile.preference,
  16         .permissive = &tomoyo_default_profile.preference,
  17         .enforcing = &tomoyo_default_profile.preference,
  18         .preference.enforcing_verbose = true,
  19         .preference.learning_max_entry = 2048,
  20         .preference.learning_verbose = false,
  21         .preference.permissive_verbose = true
  22 };
  23
  24 /* Profile version. Currently only 20090903 is defined. */
  25 static unsigned int tomoyo_profile_version;
  26
  27 /* Profile table. Memory is allocated as needed. */
  28 static struct tomoyo_profile *tomoyo_profile_ptr[TOMOYO_MAX_PROFILES];
  29
  30 /* String table for functionality that takes 4 modes. */
  31 static const char *tomoyo_mode[4] = {
  32         "disabled", "learning", "permissive", "enforcing"
  33 };
  34
  35 /* String table for /sys/kernel/security/tomoyo/profile */
  36 static const char *tomoyo_mac_keywords[TOMOYO_MAX_MAC_INDEX
  37                                        + TOMOYO_MAX_MAC_CATEGORY_INDEX] = {
  38         [TOMOYO_MAC_FILE_EXECUTE]    = "file::execute",
  39         [TOMOYO_MAC_FILE_OPEN]       = "file::open",
  40         [TOMOYO_MAC_FILE_CREATE]     = "file::create",
  41         [TOMOYO_MAC_FILE_UNLINK]     = "file::unlink",
  42         [TOMOYO_MAC_FILE_MKDIR]      = "file::mkdir",
  43         [TOMOYO_MAC_FILE_RMDIR]      = "file::rmdir",
  44         [TOMOYO_MAC_FILE_MKFIFO]     = "file::mkfifo",
  45         [TOMOYO_MAC_FILE_MKSOCK]     = "file::mksock",
  46         [TOMOYO_MAC_FILE_TRUNCATE]   = "file::truncate",
  47         [TOMOYO_MAC_FILE_SYMLINK]    = "file::symlink",
  48         [TOMOYO_MAC_FILE_REWRITE]    = "file::rewrite",
  49         [TOMOYO_MAC_FILE_MKBLOCK]    = "file::mkblock",
  50         [TOMOYO_MAC_FILE_MKCHAR]     = "file::mkchar",
  51         [TOMOYO_MAC_FILE_LINK]       = "file::link",
  52         [TOMOYO_MAC_FILE_RENAME]     = "file::rename",
  53         [TOMOYO_MAC_FILE_CHMOD]      = "file::chmod",
  54         [TOMOYO_MAC_FILE_CHOWN]      = "file::chown",
  55         [TOMOYO_MAC_FILE_CHGRP]      = "file::chgrp",
  56         [TOMOYO_MAC_FILE_IOCTL]      = "file::ioctl",
  57         [TOMOYO_MAC_FILE_CHROOT]     = "file::chroot",
  58         [TOMOYO_MAC_FILE_MOUNT]      = "file::mount",
  59         [TOMOYO_MAC_FILE_UMOUNT]     = "file::umount",
  60         [TOMOYO_MAC_FILE_PIVOT_ROOT] = "file::pivot_root",
  61         [TOMOYO_MAX_MAC_INDEX + TOMOYO_MAC_CATEGORY_FILE] = "file",
  62 };
  63
  64 /* Permit policy management by non-root user? */
  65 static bool tomoyo_manage_by_non_root;
  66
  67 /* Utility functions. */
  68
  69 /**
  70  * tomoyo_yesno - Return "yes" or "no".
  71  *
  72  * @value: Bool value.
  73  */
  74 static const char *tomoyo_yesno(const unsigned int value)
  75 {
  76         return value ? "yes" : "no";
  77 }
  78
  79 static void tomoyo_addprintf(char *buffer, int len, const char *fmt, ...)
  80 {
  81         va_list args;
  82         const int pos = strlen(buffer);
  83         va_start(args, fmt);
  84         vsnprintf(buffer + pos, len - pos - 1, fmt, args);
  85         va_end(args);
  86 }
  87
  88 /**
  89  * tomoyo_flush - Flush queued string to userspace's buffer.
  90  *
  91  * @head:   Pointer to "struct tomoyo_io_buffer".
  92  *
  93  * Returns true if all data was flushed, false otherwise.
  94  */
  95 static bool tomoyo_flush(struct tomoyo_io_buffer *head)
  96 {
  97         while (head->r.w_pos) {
  98                 const char *w = head->r.w[0];
  99                 int len = strlen(w);
 100                 if (len) {
 101                         if (len > head->read_user_buf_avail)
 102                                 len = head->read_user_buf_avail;
 103                         if (!len)
 104                                 return false;
 105                         if (copy_to_user(head->read_user_buf, w, len))
 106                                 return false;
 107                         head->read_user_buf_avail -= len;
 108                         head->read_user_buf += len;
 109                         w += len;
 110                 }
 111                 if (*w) {
 112                         head->r.w[0] = w;
 113                         return false;
 114                 }
 115                 /* Add '\0' for query. */
 116                 if (head->poll) {
 117                         if (!head->read_user_buf_avail ||
 118                             copy_to_user(head->read_user_buf, "", 1))
 119                                 return false;
 120                         head->read_user_buf_avail--;
 121                         head->read_user_buf++;
 122                 }
 123                 head->r.w_pos--;
 124                 for (len = 0; len < head->r.w_pos; len++)
 125                         head->r.w[len] = head->r.w[len + 1];
 126         }
 127         head->r.avail = 0;
 128         return true;
 129 }
 130
 131 /**
 132  * tomoyo_set_string - Queue string to "struct tomoyo_io_buffer" structure.
 133  *
 134  * @head:   Pointer to "struct tomoyo_io_buffer".
 135  * @string: String to print.
 136  *
 137  * Note that @string has to be kept valid until @head is kfree()d.
 138  * This means that char[] allocated on stack memory cannot be passed to
 139  * this function. Use tomoyo_io_printf() for char[] allocated on stack memory.
 140  */
 141 static void tomoyo_set_string(struct tomoyo_io_buffer *head, const char *string)
 142 {
 143         if (head->r.w_pos < TOMOYO_MAX_IO_READ_QUEUE) {
 144                 head->r.w[head->r.w_pos++] = string;
 145                 tomoyo_flush(head);
 146         } else
 147                 WARN_ON(1);
 148 }
 149
 150 /**
 151  * tomoyo_io_printf - printf() to "struct tomoyo_io_buffer" structure.
 152  *
 153  * @head: Pointer to "struct tomoyo_io_buffer".
 154  * @fmt:  The printf()'s format string, followed by parameters.
 155  */
 156 void tomoyo_io_printf(struct tomoyo_io_buffer *head, const char *fmt, ...)
 157 {
 158         va_list args;
 159         int len;
 160         int pos = head->r.avail;
 161         int size = head->readbuf_size - pos;
 162         if (size <= 0)
 163                 return;
 164         va_start(args, fmt);
 165         len = vsnprintf(head->read_buf + pos, size, fmt, args) + 1;
 166         va_end(args);
 167         if (pos + len >= head->readbuf_size) {
 168                 WARN_ON(1);
 169                 return;
 170         }
 171         head->r.avail += len;
 172         tomoyo_set_string(head, head->read_buf + pos);
 173 }
 174
 175 static void tomoyo_set_space(struct tomoyo_io_buffer *head)
 176 {
 177         tomoyo_set_string(head, " ");
 178 }
 179
 180 static bool tomoyo_set_lf(struct tomoyo_io_buffer *head)
 181 {
 182         tomoyo_set_string(head, "\n");
 183         return !head->r.w_pos;
 184 }
 185
 186 /**
 187  * tomoyo_print_name_union - Print a tomoyo_name_union.
 188  *
 189  * @head: Pointer to "struct tomoyo_io_buffer".
 190  * @ptr:  Pointer to "struct tomoyo_name_union".
 191  */
 192 static void tomoyo_print_name_union(struct tomoyo_io_buffer *head,
 193                                     const struct tomoyo_name_union *ptr)
 194 {
 195         tomoyo_set_space(head);
 196         if (ptr->is_group) {
 197                 tomoyo_set_string(head, "@");
 198                 tomoyo_set_string(head, ptr->group->group_name->name);
 199         } else {
 200                 tomoyo_set_string(head, ptr->filename->name);
 201         }
 202 }
 203
 204 /**
 205  * tomoyo_print_number_union - Print a tomoyo_number_union.
 206  *
 207  * @head:       Pointer to "struct tomoyo_io_buffer".
 208  * @ptr:        Pointer to "struct tomoyo_number_union".
 209  */
 210 static void tomoyo_print_number_union(struct tomoyo_io_buffer *head,
 211                                       const struct tomoyo_number_union *ptr)
 212 {
 213         tomoyo_set_space(head);
 214         if (ptr->is_group) {
 215                 tomoyo_set_string(head, "@");
 216                 tomoyo_set_string(head, ptr->group->group_name->name);
 217         } else {
 218                 int i;
 219                 unsigned long min = ptr->values[0];
 220                 const unsigned long max = ptr->values[1];
 221                 u8 min_type = ptr->min_type;
 222                 const u8 max_type = ptr->max_type;
 223                 char buffer[128];
 224                 buffer[0] = '\0';
 225                 for (i = 0; i < 2; i++) {
 226                         switch (min_type) {
 227                         case TOMOYO_VALUE_TYPE_HEXADECIMAL:
 228                                 tomoyo_addprintf(buffer, sizeof(buffer),
 229                                                  "0x%lX", min);
 230                                 break;
 231                         case TOMOYO_VALUE_TYPE_OCTAL:
 232                                 tomoyo_addprintf(buffer, sizeof(buffer),
 233                                                  "0%lo", min);
 234                                 break;
 235                         default:
 236                                 tomoyo_addprintf(buffer, sizeof(buffer),
 237                                                  "%lu", min);
 238                                 break;
 239                         }
 240                         if (min == max && min_type == max_type)
 241                                 break;
 242                         tomoyo_addprintf(buffer, sizeof(buffer), "-");
 243                         min_type = max_type;
 244                         min = max;
 245                 }
 246                 tomoyo_io_printf(head, "%s", buffer);
 247         }
 248 }
 249
 250 /**
 251  * tomoyo_assign_profile - Create a new profile.
 252  *
 253  * @profile: Profile number to create.
 254  *
 255  * Returns pointer to "struct tomoyo_profile" on success, NULL otherwise.
 256  */
 257 static struct tomoyo_profile *tomoyo_assign_profile(const unsigned int profile)
 258 {
 259         struct tomoyo_profile *ptr;
 260         struct tomoyo_profile *entry;
 261         if (profile >= TOMOYO_MAX_PROFILES)
 262                 return NULL;
 263         ptr = tomoyo_profile_ptr[profile];
 264         if (ptr)
 265                 return ptr;
 266         entry = kzalloc(sizeof(*entry), GFP_NOFS);
 267         if (mutex_lock_interruptible(&tomoyo_policy_lock))
 268                 goto out;
 269         ptr = tomoyo_profile_ptr[profile];
 270         if (!ptr && tomoyo_memory_ok(entry)) {
 271                 ptr = entry;
 272                 ptr->learning = &tomoyo_default_profile.preference;
 273                 ptr->permissive = &tomoyo_default_profile.preference;
 274                 ptr->enforcing = &tomoyo_default_profile.preference;
 275                 ptr->default_config = TOMOYO_CONFIG_DISABLED;
 276                 memset(ptr->config, TOMOYO_CONFIG_USE_DEFAULT,
 277                        sizeof(ptr->config));
 278                 mb(); /* Avoid out-of-order execution. */
 279                 tomoyo_profile_ptr[profile] = ptr;
 280                 entry = NULL;
 281         }
 282         mutex_unlock(&tomoyo_policy_lock);
 283  out:
 284         kfree(entry);
 285         return ptr;
 286 }
 287
 288 /**
 289  * tomoyo_profile - Find a profile.
 290  *
 291  * @profile: Profile number to find.
 292  *
 293  * Returns pointer to "struct tomoyo_profile".
 294  */
 295 struct tomoyo_profile *tomoyo_profile(const u8 profile)
 296 {
 297         struct tomoyo_profile *ptr = tomoyo_profile_ptr[profile];
 298         if (!tomoyo_policy_loaded)
 299                 return &tomoyo_default_profile;
 300         BUG_ON(!ptr);
 301         return ptr;
 302 }
 303
 304 static s8 tomoyo_find_yesno(const char *string, const char *find)
 305 {
 306         const char *cp = strstr(string, find);
 307         if (cp) {
 308                 cp += strlen(find);
 309                 if (!strncmp(cp, "=yes", 4))
 310                         return 1;
 311                 else if (!strncmp(cp, "=no", 3))
 312                         return 0;
 313         }
 314         return -1;
 315 }
 316
 317 static void tomoyo_set_bool(bool *b, const char *string, const char *find)
 318 {
 319         switch (tomoyo_find_yesno(string, find)) {
 320         case 1:
 321                 *b = true;
 322                 break;
 323         case 0:
 324                 *b = false;
 325                 break;
 326         }
 327 }
 328
 329 static void tomoyo_set_uint(unsigned int *i, const char *string,
 330                             const char *find)
 331 {
 332         const char *cp = strstr(string, find);
 333         if (cp)
 334                 sscanf(cp + strlen(find), "=%u", i);
 335 }
 336
 337 static void tomoyo_set_pref(const char *name, const char *value,
 338                             const bool use_default,
 339                             struct tomoyo_profile *profile)
 340 {
 341         struct tomoyo_preference **pref;
 342         bool *verbose;
 343         if (!strcmp(name, "enforcing")) {
 344                 if (use_default) {
 345                         pref = &profile->enforcing;
 346                         goto set_default;
 347                 }
 348                 profile->enforcing = &profile->preference;
 349                 verbose = &profile->preference.enforcing_verbose;
 350                 goto set_verbose;
 351         }
 352         if (!strcmp(name, "permissive")) {
 353                 if (use_default) {
 354                         pref = &profile->permissive;
 355                         goto set_default;
 356                 }
 357                 profile->permissive = &profile->preference;
 358                 verbose = &profile->preference.permissive_verbose;
 359                 goto set_verbose;
 360         }
 361         if (!strcmp(name, "learning")) {
 362                 if (use_default) {
 363                         pref = &profile->learning;
 364                         goto set_default;
 365                 }
 366                 profile->learning = &profile->preference;
 367                 tomoyo_set_uint(&profile->preference.learning_max_entry, value,
 368                              "max_entry");
 369                 verbose = &profile->preference.learning_verbose;
 370                 goto set_verbose;
 371         }
 372         return;
 373  set_default:
 374         *pref = &tomoyo_default_profile.preference;
 375         return;
 376  set_verbose:
 377         tomoyo_set_bool(verbose, value, "verbose");
 378 }
 379
 380 static int tomoyo_set_mode(char *name, const char *value,
 381                            const bool use_default,
 382                            struct tomoyo_profile *profile)
 383 {
 384         u8 i;
 385         u8 config;
 386         if (!strcmp(name, "CONFIG")) {
 387                 i = TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX;
 388                 config = profile->default_config;
 389         } else if (tomoyo_str_starts(&name, "CONFIG::")) {
 390                 config = 0;
 391                 for (i = 0; i < TOMOYO_MAX_MAC_INDEX
 392                              + TOMOYO_MAX_MAC_CATEGORY_INDEX; i++) {
 393                         if (strcmp(name, tomoyo_mac_keywords[i]))
 394                                 continue;
 395                         config = profile->config[i];
 396                         break;
 397                 }
 398                 if (i == TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX)
 399                         return -EINVAL;
 400         } else {
 401                 return -EINVAL;
 402         }
 403         if (use_default) {
 404                 config = TOMOYO_CONFIG_USE_DEFAULT;
 405         } else {
 406                 u8 mode;
 407                 for (mode = 0; mode < 4; mode++)
 408                         if (strstr(value, tomoyo_mode[mode]))
 409                                 /*
 410                                  * Update lower 3 bits in order to distinguish
 411                                  * 'config' from 'TOMOYO_CONFIG_USE_DEAFULT'.
 412                                  */
 413                                 config = (config & ~7) | mode;
 414         }
 415         if (i < TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX)
 416                 profile->config[i] = config;
 417         else if (config != TOMOYO_CONFIG_USE_DEFAULT)
 418                 profile->default_config = config;
 419         return 0;
 420 }
 421
 422 /**
 423  * tomoyo_write_profile - Write profile table.
 424  *
 425  * @head: Pointer to "struct tomoyo_io_buffer".
 426  *
 427  * Returns 0 on success, negative value otherwise.
 428  */
 429 static int tomoyo_write_profile(struct tomoyo_io_buffer *head)
 430 {
 431         char *data = head->write_buf;
 432         unsigned int i;
 433         bool use_default = false;
 434         char *cp;
 435         struct tomoyo_profile *profile;
 436         if (sscanf(data, "PROFILE_VERSION=%u", &tomoyo_profile_version) == 1)
 437                 return 0;
 438         i = simple_strtoul(data, &cp, 10);
 439         if (data == cp) {
 440                 profile = &tomoyo_default_profile;
 441         } else {
 442                 if (*cp != '-')
 443                         return -EINVAL;
 444                 data = cp + 1;
 445                 profile = tomoyo_assign_profile(i);
 446                 if (!profile)
 447                         return -EINVAL;
 448         }
 449         cp = strchr(data, '=');
 450         if (!cp)
 451                 return -EINVAL;
 452         *cp++ = '\0';
 453         if (profile != &tomoyo_default_profile)
 454                 use_default = strstr(cp, "use_default") != NULL;
 455         if (tomoyo_str_starts(&data, "PREFERENCE::")) {
 456                 tomoyo_set_pref(data, cp, use_default, profile);
 457                 return 0;
 458         }
 459         if (profile == &tomoyo_default_profile)
 460                 return -EINVAL;
 461         if (!strcmp(data, "COMMENT")) {
 462                 const struct tomoyo_path_info *old_comment = profile->comment;
 463                 profile->comment = tomoyo_get_name(cp);
 464                 tomoyo_put_name(old_comment);
 465                 return 0;
 466         }
 467         return tomoyo_set_mode(data, cp, use_default, profile);
 468 }
 469
 470 static void tomoyo_print_preference(struct tomoyo_io_buffer *head,
 471                                     const int idx)
 472 {
 473         struct tomoyo_preference *pref = &tomoyo_default_profile.preference;
 474         const struct tomoyo_profile *profile = idx >= 0 ?
 475                 tomoyo_profile_ptr[idx] : NULL;
 476         char buffer[16] = "";
 477         if (profile) {
 478                 buffer[sizeof(buffer) - 1] = '\0';
 479                 snprintf(buffer, sizeof(buffer) - 1, "%u-", idx);
 480         }
 481         if (profile) {
 482                 pref = profile->learning;
 483                 if (pref == &tomoyo_default_profile.preference)
 484                         goto skip1;
 485         }
 486         tomoyo_io_printf(head, "%sPREFERENCE::%s={ "
 487                          "verbose=%s max_entry=%u }\n",
 488                          buffer, "learning",
 489                          tomoyo_yesno(pref->learning_verbose),
 490                          pref->learning_max_entry);
 491  skip1:
 492         if (profile) {
 493                 pref = profile->permissive;
 494                 if (pref == &tomoyo_default_profile.preference)
 495                         goto skip2;
 496         }
 497         tomoyo_io_printf(head, "%sPREFERENCE::%s={ verbose=%s }\n",
 498                          buffer, "permissive",
 499                          tomoyo_yesno(pref->permissive_verbose));
 500  skip2:
 501         if (profile) {
 502                 pref = profile->enforcing;
 503                 if (pref == &tomoyo_default_profile.preference)
 504                         return;
 505         }
 506         tomoyo_io_printf(head, "%sPREFERENCE::%s={ verbose=%s }\n",
 507                          buffer, "enforcing",
 508                          tomoyo_yesno(pref->enforcing_verbose));
 509 }
 510
 511 static void tomoyo_print_config(struct tomoyo_io_buffer *head, const u8 config)
 512 {
 513         tomoyo_io_printf(head, "={ mode=%s }\n", tomoyo_mode[config & 3]);
 514 }
 515
 516 /**
 517  * tomoyo_read_profile - Read profile table.
 518  *
 519  * @head: Pointer to "struct tomoyo_io_buffer".
 520  */
 521 static void tomoyo_read_profile(struct tomoyo_io_buffer *head)
 522 {
 523         u8 index;
 524         const struct tomoyo_profile *profile;
 525  next:
 526         index = head->r.index;
 527         profile = tomoyo_profile_ptr[index];
 528         switch (head->r.step) {
 529         case 0:
 530                 tomoyo_io_printf(head, "PROFILE_VERSION=%s\n", "20090903");
 531                 tomoyo_print_preference(head, -1);
 532                 head->r.step++;
 533                 break;
 534         case 1:
 535                 for ( ; head->r.index < TOMOYO_MAX_PROFILES;
 536                       head->r.index++)
 537                         if (tomoyo_profile_ptr[head->r.index])
 538                                 break;
 539                 if (head->r.index == TOMOYO_MAX_PROFILES)
 540                         return;
 541                 head->r.step++;
 542                 break;
 543         case 2:
 544                 {
 545                         const struct tomoyo_path_info *comment =
 546                                 profile->comment;
 547                         tomoyo_io_printf(head, "%u-COMMENT=", index);
 548                         tomoyo_set_string(head, comment ? comment->name : "");
 549                         tomoyo_set_lf(head);
 550                         head->r.step++;
 551                 }
 552                 break;
 553         case 3:
 554                 {
 555                         tomoyo_io_printf(head, "%u-%s", index, "CONFIG");
 556                         tomoyo_print_config(head, profile->default_config);
 557                         head->r.bit = 0;
 558                         head->r.step++;
 559                 }
 560                 break;
 561         case 4:
 562                 for ( ; head->r.bit < TOMOYO_MAX_MAC_INDEX
 563                               + TOMOYO_MAX_MAC_CATEGORY_INDEX; head->r.bit++) {
 564                         const u8 i = head->r.bit;
 565                         const u8 config = profile->config[i];
 566                         if (config == TOMOYO_CONFIG_USE_DEFAULT)
 567                                 continue;
 568                         tomoyo_io_printf(head, "%u-%s%s", index, "CONFIG::",
 569                                          tomoyo_mac_keywords[i]);
 570                         tomoyo_print_config(head, config);
 571                         head->r.bit++;
 572                         break;
 573                 }
 574                 if (head->r.bit == TOMOYO_MAX_MAC_INDEX
 575                     + TOMOYO_MAX_MAC_CATEGORY_INDEX) {
 576                         tomoyo_print_preference(head, index);
 577                         head->r.index++;
 578                         head->r.step = 1;
 579                 }
 580                 break;
 581         }
 582         if (tomoyo_flush(head))
 583                 goto next;
 584 }
 585
 586 static bool tomoyo_same_manager(const struct tomoyo_acl_head *a,
 587                                 const struct tomoyo_acl_head *b)
 588 {
 589         return container_of(a, struct tomoyo_manager, head)->manager ==
 590                 container_of(b, struct tomoyo_manager, head)->manager;
 591 }
 592
 593 /**
 594  * tomoyo_update_manager_entry - Add a manager entry.
 595  *
 596  * @manager:   The path to manager or the domainnamme.
 597  * @is_delete: True if it is a delete request.
 598  *
 599  * Returns 0 on success, negative value otherwise.
 600  *
 601  * Caller holds tomoyo_read_lock().
 602  */
 603 static int tomoyo_update_manager_entry(const char *manager,
 604                                        const bool is_delete)
 605 {
 606         struct tomoyo_manager e = { };
 607         int error;
 608
 609         if (tomoyo_domain_def(manager)) {
 610                 if (!tomoyo_correct_domain(manager))
 611                         return -EINVAL;
 612                 e.is_domain = true;
 613         } else {
 614                 if (!tomoyo_correct_path(manager))
 615                         return -EINVAL;
 616         }
 617         e.manager = tomoyo_get_name(manager);
 618         if (!e.manager)
 619                 return -ENOMEM;
 620         error = tomoyo_update_policy(&e.head, sizeof(e), is_delete,
 621                                      &tomoyo_policy_list[TOMOYO_ID_MANAGER],
 622                                      tomoyo_same_manager);
 623         tomoyo_put_name(e.manager);
 624         return error;
 625 }
 626
 627 /**
 628  * tomoyo_write_manager - Write manager policy.
 629  *
 630  * @head: Pointer to "struct tomoyo_io_buffer".
 631  *
 632  * Returns 0 on success, negative value otherwise.
 633  *
 634  * Caller holds tomoyo_read_lock().
 635  */
 636 static int tomoyo_write_manager(struct tomoyo_io_buffer *head)
 637 {
 638         char *data = head->write_buf;
 639         bool is_delete = tomoyo_str_starts(&data, TOMOYO_KEYWORD_DELETE);
 640
 641         if (!strcmp(data, "manage_by_non_root")) {
 642                 tomoyo_manage_by_non_root = !is_delete;
 643                 return 0;
 644         }
 645         return tomoyo_update_manager_entry(data, is_delete);
 646 }
 647
 648 /**
 649  * tomoyo_read_manager - Read manager policy.
 650  *
 651  * @head: Pointer to "struct tomoyo_io_buffer".
 652  *
 653  * Caller holds tomoyo_read_lock().
 654  */
 655 static void tomoyo_read_manager(struct tomoyo_io_buffer *head)
 656 {
 657         if (head->r.eof)
 658                 return;
 659         list_for_each_cookie(head->r.acl,
 660                              &tomoyo_policy_list[TOMOYO_ID_MANAGER]) {
 661                 struct tomoyo_manager *ptr =
 662                         list_entry(head->r.acl, typeof(*ptr), head.list);
 663                 if (ptr->head.is_deleted)
 664                         continue;
 665                 if (!tomoyo_flush(head))
 666                         return;
 667                 tomoyo_set_string(head, ptr->manager->name);
 668                 tomoyo_set_lf(head);
 669         }
 670         head->r.eof = true;
 671 }
 672
 673 /**
 674  * tomoyo_manager - Check whether the current process is a policy manager.
 675  *
 676  * Returns true if the current process is permitted to modify policy
 677  * via /sys/kernel/security/tomoyo/ interface.
 678  *
 679  * Caller holds tomoyo_read_lock().
 680  */
 681 static bool tomoyo_manager(void)
 682 {
 683         struct tomoyo_manager *ptr;
 684         const char *exe;
 685         const struct task_struct *task = current;
 686         const struct tomoyo_path_info *domainname = tomoyo_domain()->domainname;
 687         bool found = false;
 688
 689         if (!tomoyo_policy_loaded)
 690                 return true;
 691         if (!tomoyo_manage_by_non_root && (task->cred->uid || task->cred->euid))
 692                 return false;
 693         list_for_each_entry_rcu(ptr, &tomoyo_policy_list[TOMOYO_ID_MANAGER],
 694                                 head.list) {
 695                 if (!ptr->head.is_deleted && ptr->is_domain
 696                     && !tomoyo_pathcmp(domainname, ptr->manager)) {
 697                         found = true;
 698                         break;
 699                 }
 700         }
 701         if (found)
 702                 return true;
 703         exe = tomoyo_get_exe();
 704         if (!exe)
 705                 return false;
 706         list_for_each_entry_rcu(ptr, &tomoyo_policy_list[TOMOYO_ID_MANAGER],
 707                                 head.list) {
 708                 if (!ptr->head.is_deleted && !ptr->is_domain
 709                     && !strcmp(exe, ptr->manager->name)) {
 710                         found = true;
 711                         break;
 712                 }
 713         }
 714         if (!found) { /* Reduce error messages. */
 715                 static pid_t last_pid;
 716                 const pid_t pid = current->pid;
 717                 if (last_pid != pid) {
 718                         printk(KERN_WARNING "%s ( %s ) is not permitted to "
 719                                "update policies.\n", domainname->name, exe);
 720                         last_pid = pid;
 721                 }
 722         }
 723         kfree(exe);
 724         return found;
 725 }
 726
 727 /**
 728  * tomoyo_select_one - Parse select command.
 729  *
 730  * @head: Pointer to "struct tomoyo_io_buffer".
 731  * @data: String to parse.
 732  *
 733  * Returns true on success, false otherwise.
 734  *
 735  * Caller holds tomoyo_read_lock().
 736  */
 737 static bool tomoyo_select_one(struct tomoyo_io_buffer *head, const char *data)
 738 {
 739         unsigned int pid;
 740         struct tomoyo_domain_info *domain = NULL;
 741         bool global_pid = false;
 742
 743         if (!strcmp(data, "allow_execute")) {
 744                 head->r.print_execute_only = true;
 745                 return true;
 746         }
 747         if (sscanf(data, "pid=%u", &pid) == 1 ||
 748             (global_pid = true, sscanf(data, "global-pid=%u", &pid) == 1)) {
 749                 struct task_struct *p;
 750                 rcu_read_lock();
 751                 read_lock(&tasklist_lock);
 752                 if (global_pid)
 753                         p = find_task_by_pid_ns(pid, &init_pid_ns);
 754                 else
 755                         p = find_task_by_vpid(pid);
 756                 if (p)
 757                         domain = tomoyo_real_domain(p);
 758                 read_unlock(&tasklist_lock);
 759                 rcu_read_unlock();
 760         } else if (!strncmp(data, "domain=", 7)) {
 761                 if (tomoyo_domain_def(data + 7))
 762                         domain = tomoyo_find_domain(data + 7);
 763         } else
 764                 return false;
 765         head->write_var1 = domain;
 766         /* Accessing read_buf is safe because head->io_sem is held. */
 767         if (!head->read_buf)
 768                 return true; /* Do nothing if open(O_WRONLY). */
 769         memset(&head->r, 0, sizeof(head->r));
 770         head->r.print_this_domain_only = true;
 771         head->r.eof = !domain;
 772         head->r.domain = &domain->list;
 773         tomoyo_io_printf(head, "# select %s\n", data);
 774         if (domain && domain->is_deleted)
 775                 tomoyo_io_printf(head, "# This is a deleted domain.\n");
 776         return true;
 777 }
 778
 779 /**
 780  * tomoyo_delete_domain - Delete a domain.
 781  *
 782  * @domainname: The name of domain.
 783  *
 784  * Returns 0.
 785  *
 786  * Caller holds tomoyo_read_lock().
 787  */
 788 static int tomoyo_delete_domain(char *domainname)
 789 {
 790         struct tomoyo_domain_info *domain;
 791         struct tomoyo_path_info name;
 792
 793         name.name = domainname;
 794         tomoyo_fill_path_info(&name);
 795         if (mutex_lock_interruptible(&tomoyo_policy_lock))
 796                 return 0;
 797         /* Is there an active domain? */
 798         list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
 799                 /* Never delete tomoyo_kernel_domain */
 800                 if (domain == &tomoyo_kernel_domain)
 801                         continue;
 802                 if (domain->is_deleted ||
 803                     tomoyo_pathcmp(domain->domainname, &name))
 804                         continue;
 805                 domain->is_deleted = true;
 806                 break;
 807         }
 808         mutex_unlock(&tomoyo_policy_lock);
 809         return 0;
 810 }
 811
 812 /**
 813  * tomoyo_write_domain2 - Write domain policy.
 814  *
 815  * @head: Pointer to "struct tomoyo_io_buffer".
 816  *
 817  * Returns 0 on success, negative value otherwise.
 818  *
 819  * Caller holds tomoyo_read_lock().
 820  */
 821 static int tomoyo_write_domain2(char *data, struct tomoyo_domain_info *domain,
 822                                 const bool is_delete)
 823 {
 824         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_ALLOW_MOUNT))
 825                 return tomoyo_write_mount(data, domain, is_delete);
 826         return tomoyo_write_file(data, domain, is_delete);
 827 }
 828
 829 /**
 830  * tomoyo_write_domain - Write domain policy.
 831  *
 832  * @head: Pointer to "struct tomoyo_io_buffer".
 833  *
 834  * Returns 0 on success, negative value otherwise.
 835  *
 836  * Caller holds tomoyo_read_lock().
 837  */
 838 static int tomoyo_write_domain(struct tomoyo_io_buffer *head)
 839 {
 840         char *data = head->write_buf;
 841         struct tomoyo_domain_info *domain = head->write_var1;
 842         bool is_delete = false;
 843         bool is_select = false;
 844         unsigned int profile;
 845
 846         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_DELETE))
 847                 is_delete = true;
 848         else if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_SELECT))
 849                 is_select = true;
 850         if (is_select && tomoyo_select_one(head, data))
 851                 return 0;
 852         /* Don't allow updating policies by non manager programs. */
 853         if (!tomoyo_manager())
 854                 return -EPERM;
 855         if (tomoyo_domain_def(data)) {
 856                 domain = NULL;
 857                 if (is_delete)
 858                         tomoyo_delete_domain(data);
 859                 else if (is_select)
 860                         domain = tomoyo_find_domain(data);
 861                 else
 862                         domain = tomoyo_assign_domain(data, 0);
 863                 head->write_var1 = domain;
 864                 return 0;
 865         }
 866         if (!domain)
 867                 return -EINVAL;
 868
 869         if (sscanf(data, TOMOYO_KEYWORD_USE_PROFILE "%u", &profile) == 1
 870             && profile < TOMOYO_MAX_PROFILES) {
 871                 if (tomoyo_profile_ptr[profile] || !tomoyo_policy_loaded)
 872                         domain->profile = (u8) profile;
 873                 return 0;
 874         }
 875         if (!strcmp(data, TOMOYO_KEYWORD_IGNORE_GLOBAL_ALLOW_READ)) {
 876                 domain->ignore_global_allow_read = !is_delete;
 877                 return 0;
 878         }
 879         if (!strcmp(data, TOMOYO_KEYWORD_QUOTA_EXCEEDED)) {
 880                 domain->quota_warned = !is_delete;
 881                 return 0;
 882         }
 883         if (!strcmp(data, TOMOYO_KEYWORD_TRANSITION_FAILED)) {
 884                 domain->transition_failed = !is_delete;
 885                 return 0;
 886         }
 887         return tomoyo_write_domain2(data, domain, is_delete);
 888 }
 889
 890 /**
 891  * tomoyo_fns - Find next set bit.
 892  *
 893  * @perm: 8 bits value.
 894  * @bit:  First bit to find.
 895  *
 896  * Returns next on-bit on success, 8 otherwise.
 897  */
 898 static u8 tomoyo_fns(const u8 perm, u8 bit)
 899 {
 900         for ( ; bit < 8; bit++)
 901                 if (perm & (1 << bit))
 902                         break;
 903         return bit;
 904 }
 905
 906 /**
 907  * tomoyo_print_entry - Print an ACL entry.
 908  *
 909  * @head: Pointer to "struct tomoyo_io_buffer".
 910  * @acl:  Pointer to an ACL entry.
 911  *
 912  * Returns true on success, false otherwise.
 913  */
 914 static bool tomoyo_print_entry(struct tomoyo_io_buffer *head,
 915                                struct tomoyo_acl_info *acl)
 916 {
 917         const u8 acl_type = acl->type;
 918         u8 bit;
 919
 920         if (acl->is_deleted)
 921                 return true;
 922  next:
 923         bit = head->r.bit;
 924         if (!tomoyo_flush(head))
 925                 return false;
 926         else if (acl_type == TOMOYO_TYPE_PATH_ACL) {
 927                 struct tomoyo_path_acl *ptr =
 928                         container_of(acl, typeof(*ptr), head);
 929                 const u16 perm = ptr->perm;
 930                 for ( ; bit < TOMOYO_MAX_PATH_OPERATION; bit++) {
 931                         if (!(perm & (1 << bit)))
 932                                 continue;
 933                         if (head->r.print_execute_only &&
 934                             bit != TOMOYO_TYPE_EXECUTE)
 935                                 continue;
 936                         /* Print "read/write" instead of "read" and "write". */
 937                         if ((bit == TOMOYO_TYPE_READ ||
 938                              bit == TOMOYO_TYPE_WRITE)
 939                             && (perm & (1 << TOMOYO_TYPE_READ_WRITE)))
 940                                 continue;
 941                         break;
 942                 }
 943                 if (bit >= TOMOYO_MAX_PATH_OPERATION)
 944                         goto done;
 945                 tomoyo_io_printf(head, "allow_%s", tomoyo_path_keyword[bit]);
 946                 tomoyo_print_name_union(head, &ptr->name);
 947         } else if (head->r.print_execute_only) {
 948                 return true;
 949         } else if (acl_type == TOMOYO_TYPE_PATH2_ACL) {
 950                 struct tomoyo_path2_acl *ptr =
 951                         container_of(acl, typeof(*ptr), head);
 952                 bit = tomoyo_fns(ptr->perm, bit);
 953                 if (bit >= TOMOYO_MAX_PATH2_OPERATION)
 954                         goto done;
 955                 tomoyo_io_printf(head, "allow_%s", tomoyo_path2_keyword[bit]);
 956                 tomoyo_print_name_union(head, &ptr->name1);
 957                 tomoyo_print_name_union(head, &ptr->name2);
 958         } else if (acl_type == TOMOYO_TYPE_PATH_NUMBER_ACL) {
 959                 struct tomoyo_path_number_acl *ptr =
 960                         container_of(acl, typeof(*ptr), head);
 961                 bit = tomoyo_fns(ptr->perm, bit);
 962                 if (bit >= TOMOYO_MAX_PATH_NUMBER_OPERATION)
 963                         goto done;
 964                 tomoyo_io_printf(head, "allow_%s",
 965                                  tomoyo_path_number_keyword[bit]);
 966                 tomoyo_print_name_union(head, &ptr->name);
 967                 tomoyo_print_number_union(head, &ptr->number);
 968         } else if (acl_type == TOMOYO_TYPE_MKDEV_ACL) {
 969                 struct tomoyo_mkdev_acl *ptr =
 970                         container_of(acl, typeof(*ptr), head);
 971                 bit = tomoyo_fns(ptr->perm, bit);
 972                 if (bit >= TOMOYO_MAX_MKDEV_OPERATION)
 973                         goto done;
 974                 tomoyo_io_printf(head, "allow_%s", tomoyo_mkdev_keyword[bit]);
 975                 tomoyo_print_name_union(head, &ptr->name);
 976                 tomoyo_print_number_union(head, &ptr->mode);
 977                 tomoyo_print_number_union(head, &ptr->major);
 978                 tomoyo_print_number_union(head, &ptr->minor);
 979         } else if (acl_type == TOMOYO_TYPE_MOUNT_ACL) {
 980                 struct tomoyo_mount_acl *ptr =
 981                         container_of(acl, typeof(*ptr), head);
 982                 tomoyo_io_printf(head, "allow_mount");
 983                 tomoyo_print_name_union(head, &ptr->dev_name);
 984                 tomoyo_print_name_union(head, &ptr->dir_name);
 985                 tomoyo_print_name_union(head, &ptr->fs_type);
 986                 tomoyo_print_number_union(head, &ptr->flags);
 987         }
 988         head->r.bit = bit + 1;
 989         tomoyo_io_printf(head, "\n");
 990         if (acl_type != TOMOYO_TYPE_MOUNT_ACL)
 991                 goto next;
 992  done:
 993         head->r.bit = 0;
 994         return true;
 995 }
 996
 997 /**
 998  * tomoyo_read_domain2 - Read domain policy.
 999  *
1000  * @head:   Pointer to "struct tomoyo_io_buffer".
1001  * @domain: Pointer to "struct tomoyo_domain_info".
1002  *
1003  * Caller holds tomoyo_read_lock().
1004  *
1005  * Returns true on success, false otherwise.
1006  */
1007 static bool tomoyo_read_domain2(struct tomoyo_io_buffer *head,
1008                                 struct tomoyo_domain_info *domain)
1009 {
1010         list_for_each_cookie(head->r.acl, &domain->acl_info_list) {
1011                 struct tomoyo_acl_info *ptr =
1012                         list_entry(head->r.acl, typeof(*ptr), list);
1013                 if (!tomoyo_print_entry(head, ptr))
1014                         return false;
1015         }
1016         head->r.acl = NULL;
1017         return true;
1018 }
1019
1020 /**
1021  * tomoyo_read_domain - Read domain policy.
1022  *
1023  * @head: Pointer to "struct tomoyo_io_buffer".
1024  *
1025  * Caller holds tomoyo_read_lock().
1026  */
1027 static void tomoyo_read_domain(struct tomoyo_io_buffer *head)
1028 {
1029         if (head->r.eof)
1030                 return;
1031         list_for_each_cookie(head->r.domain, &tomoyo_domain_list) {
1032                 struct tomoyo_domain_info *domain =
1033                         list_entry(head->r.domain, typeof(*domain), list);
1034                 switch (head->r.step) {
1035                 case 0:
1036                         if (domain->is_deleted &&
1037                             !head->r.print_this_domain_only)
1038                                 continue;
1039                         /* Print domainname and flags. */
1040                         tomoyo_set_string(head, domain->domainname->name);
1041                         tomoyo_set_lf(head);
1042                         tomoyo_io_printf(head,
1043                                          TOMOYO_KEYWORD_USE_PROFILE "%u\n",
1044                                          domain->profile);
1045                         if (domain->quota_warned)
1046                                 tomoyo_set_string(head, "quota_exceeded\n");
1047                         if (domain->transition_failed)
1048                                 tomoyo_set_string(head, "transition_failed\n");
1049                         if (domain->ignore_global_allow_read)
1050                                 tomoyo_set_string(head,
1051                                        TOMOYO_KEYWORD_IGNORE_GLOBAL_ALLOW_READ
1052                                                   "\n");
1053                         head->r.step++;
1054                         tomoyo_set_lf(head);
1055                         /* fall through */
1056                 case 1:
1057                         if (!tomoyo_read_domain2(head, domain))
1058                                 return;
1059                         head->r.step++;
1060                         if (!tomoyo_set_lf(head))
1061                                 return;
1062                         /* fall through */
1063                 case 2:
1064                         head->r.step = 0;
1065                         if (head->r.print_this_domain_only)
1066                                 goto done;
1067                 }
1068         }
1069  done:
1070         head->r.eof = true;
1071 }
1072
1073 /**
1074  * tomoyo_write_domain_profile - Assign profile for specified domain.
1075  *
1076  * @head: Pointer to "struct tomoyo_io_buffer".
1077  *
1078  * Returns 0 on success, -EINVAL otherwise.
1079  *
1080  * This is equivalent to doing
1081  *
1082  *     ( echo "select " $domainname; echo "use_profile " $profile ) |
1083  *     /usr/sbin/tomoyo-loadpolicy -d
1084  *
1085  * Caller holds tomoyo_read_lock().
1086  */
1087 static int tomoyo_write_domain_profile(struct tomoyo_io_buffer *head)
1088 {
1089         char *data = head->write_buf;
1090         char *cp = strchr(data, ' ');
1091         struct tomoyo_domain_info *domain;
1092         unsigned long profile;
1093
1094         if (!cp)
1095                 return -EINVAL;
1096         *cp = '\0';
1097         domain = tomoyo_find_domain(cp + 1);
1098         if (strict_strtoul(data, 10, &profile))
1099                 return -EINVAL;
1100         if (domain && profile < TOMOYO_MAX_PROFILES
1101             && (tomoyo_profile_ptr[profile] || !tomoyo_policy_loaded))
1102                 domain->profile = (u8) profile;
1103         return 0;
1104 }
1105
1106 /**
1107  * tomoyo_read_domain_profile - Read only domainname and profile.
1108  *
1109  * @head: Pointer to "struct tomoyo_io_buffer".
1110  *
1111  * Returns list of profile number and domainname pairs.
1112  *
1113  * This is equivalent to doing
1114  *
1115  *     grep -A 1 '^<kernel>' /sys/kernel/security/tomoyo/domain_policy |
1116  *     awk ' { if ( domainname == "" ) { if ( $1 == "<kernel>" )
1117  *     domainname = $0; } else if ( $1 == "use_profile" ) {
1118  *     print $2 " " domainname; domainname = ""; } } ; '
1119  *
1120  * Caller holds tomoyo_read_lock().
1121  */
1122 static void tomoyo_read_domain_profile(struct tomoyo_io_buffer *head)
1123 {
1124         if (head->r.eof)
1125                 return;
1126         list_for_each_cookie(head->r.domain, &tomoyo_domain_list) {
1127                 struct tomoyo_domain_info *domain =
1128                         list_entry(head->r.domain, typeof(*domain), list);
1129                 if (domain->is_deleted)
1130                         continue;
1131                 if (!tomoyo_flush(head))
1132                         return;
1133                 tomoyo_io_printf(head, "%u ", domain->profile);
1134                 tomoyo_set_string(head, domain->domainname->name);
1135                 tomoyo_set_lf(head);
1136         }
1137         head->r.eof = true;
1138 }
1139
1140 /**
1141  * tomoyo_write_pid: Specify PID to obtain domainname.
1142  *
1143  * @head: Pointer to "struct tomoyo_io_buffer".
1144  *
1145  * Returns 0.
1146  */
1147 static int tomoyo_write_pid(struct tomoyo_io_buffer *head)
1148 {
1149         head->r.eof = false;
1150         return 0;
1151 }
1152
1153 /**
1154  * tomoyo_read_pid - Get domainname of the specified PID.
1155  *
1156  * @head: Pointer to "struct tomoyo_io_buffer".
1157  *
1158  * Returns the domainname which the specified PID is in on success,
1159  * empty string otherwise.
1160  * The PID is specified by tomoyo_write_pid() so that the user can obtain
1161  * using read()/write() interface rather than sysctl() interface.
1162  */
1163 static void tomoyo_read_pid(struct tomoyo_io_buffer *head)
1164 {
1165         char *buf = head->write_buf;
1166         bool global_pid = false;
1167         unsigned int pid;
1168         struct task_struct *p;
1169         struct tomoyo_domain_info *domain = NULL;
1170
1171         /* Accessing write_buf is safe because head->io_sem is held. */
1172         if (!buf) {
1173                 head->r.eof = true;
1174                 return; /* Do nothing if open(O_RDONLY). */
1175         }
1176         if (head->r.w_pos || head->r.eof)
1177                 return;
1178         head->r.eof = true;
1179         if (tomoyo_str_starts(&buf, "global-pid "))
1180                 global_pid = true;
1181         pid = (unsigned int) simple_strtoul(buf, NULL, 10);
1182         rcu_read_lock();
1183         read_lock(&tasklist_lock);
1184         if (global_pid)
1185                 p = find_task_by_pid_ns(pid, &init_pid_ns);
1186         else
1187                 p = find_task_by_vpid(pid);
1188         if (p)
1189                 domain = tomoyo_real_domain(p);
1190         read_unlock(&tasklist_lock);
1191         rcu_read_unlock();
1192         if (!domain)
1193                 return;
1194         tomoyo_io_printf(head, "%u %u ", pid, domain->profile);
1195         tomoyo_set_string(head, domain->domainname->name);
1196 }
1197
1198 static const char *tomoyo_transition_type[TOMOYO_MAX_TRANSITION_TYPE] = {
1199         [TOMOYO_TRANSITION_CONTROL_NO_INITIALIZE]
1200         = TOMOYO_KEYWORD_NO_INITIALIZE_DOMAIN,
1201         [TOMOYO_TRANSITION_CONTROL_INITIALIZE]
1202         = TOMOYO_KEYWORD_INITIALIZE_DOMAIN,
1203         [TOMOYO_TRANSITION_CONTROL_NO_KEEP] = TOMOYO_KEYWORD_NO_KEEP_DOMAIN,
1204         [TOMOYO_TRANSITION_CONTROL_KEEP] = TOMOYO_KEYWORD_KEEP_DOMAIN
1205 };
1206
1207 static const char *tomoyo_group_name[TOMOYO_MAX_GROUP] = {
1208         [TOMOYO_PATH_GROUP] = TOMOYO_KEYWORD_PATH_GROUP,
1209         [TOMOYO_NUMBER_GROUP] = TOMOYO_KEYWORD_NUMBER_GROUP
1210 };
1211
1212 /**
1213  * tomoyo_write_exception - Write exception policy.
1214  *
1215  * @head: Pointer to "struct tomoyo_io_buffer".
1216  *
1217  * Returns 0 on success, negative value otherwise.
1218  *
1219  * Caller holds tomoyo_read_lock().
1220  */
1221 static int tomoyo_write_exception(struct tomoyo_io_buffer *head)
1222 {
1223         char *data = head->write_buf;
1224         bool is_delete = tomoyo_str_starts(&data, TOMOYO_KEYWORD_DELETE);
1225         u8 i;
1226         static const struct {
1227                 const char *keyword;
1228                 int (*write) (char *, const bool);
1229         } tomoyo_callback[4] = {
1230                 { TOMOYO_KEYWORD_AGGREGATOR, tomoyo_write_aggregator },
1231                 { TOMOYO_KEYWORD_FILE_PATTERN, tomoyo_write_pattern },
1232                 { TOMOYO_KEYWORD_DENY_REWRITE, tomoyo_write_no_rewrite },
1233                 { TOMOYO_KEYWORD_ALLOW_READ, tomoyo_write_globally_readable },
1234         };
1235
1236         for (i = 0; i < TOMOYO_MAX_TRANSITION_TYPE; i++)
1237                 if (tomoyo_str_starts(&data, tomoyo_transition_type[i]))
1238                         return tomoyo_write_transition_control(data, is_delete,
1239                                                                i);
1240         for (i = 0; i < 4; i++)
1241                 if (tomoyo_str_starts(&data, tomoyo_callback[i].keyword))
1242                         return tomoyo_callback[i].write(data, is_delete);
1243         for (i = 0; i < TOMOYO_MAX_GROUP; i++)
1244                 if (tomoyo_str_starts(&data, tomoyo_group_name[i]))
1245                         return tomoyo_write_group(data, is_delete, i);
1246         return -EINVAL;
1247 }
1248
1249 /**
1250  * tomoyo_read_group - Read "struct tomoyo_path_group"/"struct tomoyo_number_group" list.
1251  *
1252  * @head: Pointer to "struct tomoyo_io_buffer".
1253  * @idx:  Index number.
1254  *
1255  * Returns true on success, false otherwise.
1256  *
1257  * Caller holds tomoyo_read_lock().
1258  */
1259 static bool tomoyo_read_group(struct tomoyo_io_buffer *head, const int idx)
1260 {
1261         list_for_each_cookie(head->r.group, &tomoyo_group_list[idx]) {
1262                 struct tomoyo_group *group =
1263                         list_entry(head->r.group, typeof(*group), list);
1264                 list_for_each_cookie(head->r.acl, &group->member_list) {
1265                         struct tomoyo_acl_head *ptr =
1266                                 list_entry(head->r.acl, typeof(*ptr), list);
1267                         if (ptr->is_deleted)
1268                                 continue;
1269                         if (!tomoyo_flush(head))
1270                                 return false;
1271                         tomoyo_set_string(head, tomoyo_group_name[idx]);
1272                         tomoyo_set_string(head, group->group_name->name);
1273                         if (idx == TOMOYO_PATH_GROUP) {
1274                                 tomoyo_set_space(head);
1275                                 tomoyo_set_string(head, container_of
1276                                                (ptr, struct tomoyo_path_group,
1277                                                 head)->member_name->name);
1278                         } else if (idx == TOMOYO_NUMBER_GROUP) {
1279                                 tomoyo_print_number_union(head, &container_of
1280                                                           (ptr,
1281                                                    struct tomoyo_number_group,
1282                                                            head)->number);
1283                         }
1284                         tomoyo_set_lf(head);
1285                 }
1286                 head->r.acl = NULL;
1287         }
1288         head->r.group = NULL;
1289         return true;
1290 }
1291
1292 /**
1293  * tomoyo_read_policy - Read "struct tomoyo_..._entry" list.
1294  *
1295  * @head: Pointer to "struct tomoyo_io_buffer".
1296  * @idx:  Index number.
1297  *
1298  * Returns true on success, false otherwise.
1299  *
1300  * Caller holds tomoyo_read_lock().
1301  */
1302 static bool tomoyo_read_policy(struct tomoyo_io_buffer *head, const int idx)
1303 {
1304         list_for_each_cookie(head->r.acl, &tomoyo_policy_list[idx]) {
1305                 struct tomoyo_acl_head *acl =
1306                         container_of(head->r.acl, typeof(*acl), list);
1307                 if (acl->is_deleted)
1308                         continue;
1309                 if (!tomoyo_flush(head))
1310                         return false;
1311                 switch (idx) {
1312                 case TOMOYO_ID_TRANSITION_CONTROL:
1313                         {
1314                                 struct tomoyo_transition_control *ptr =
1315                                         container_of(acl, typeof(*ptr), head);
1316                                 tomoyo_set_string(head,
1317                                                   tomoyo_transition_type
1318                                                   [ptr->type]);
1319                                 if (ptr->program)
1320                                         tomoyo_set_string(head,
1321                                                           ptr->program->name);
1322                                 if (ptr->program && ptr->domainname)
1323                                         tomoyo_set_string(head, " from ");
1324                                 if (ptr->domainname)
1325                                         tomoyo_set_string(head,
1326                                                           ptr->domainname->
1327                                                           name);
1328                         }
1329                         break;
1330                 case TOMOYO_ID_GLOBALLY_READABLE:
1331                         {
1332                                 struct tomoyo_readable_file *ptr =
1333                                         container_of(acl, typeof(*ptr), head);
1334                                 tomoyo_set_string(head,
1335                                                   TOMOYO_KEYWORD_ALLOW_READ);
1336                                 tomoyo_set_string(head, ptr->filename->name);
1337                         }
1338                         break;
1339                 case TOMOYO_ID_AGGREGATOR:
1340                         {
1341                                 struct tomoyo_aggregator *ptr =
1342                                         container_of(acl, typeof(*ptr), head);
1343                                 tomoyo_set_string(head,
1344                                                   TOMOYO_KEYWORD_AGGREGATOR);
1345                                 tomoyo_set_string(head,
1346                                                   ptr->original_name->name);
1347                                 tomoyo_set_space(head);
1348                                 tomoyo_set_string(head,
1349                                                ptr->aggregated_name->name);
1350                         }
1351                         break;
1352                 case TOMOYO_ID_PATTERN:
1353                         {
1354                                 struct tomoyo_no_pattern *ptr =
1355                                         container_of(acl, typeof(*ptr), head);
1356                                 tomoyo_set_string(head,
1357                                                   TOMOYO_KEYWORD_FILE_PATTERN);
1358                                 tomoyo_set_string(head, ptr->pattern->name);
1359                         }
1360                         break;
1361                 case TOMOYO_ID_NO_REWRITE:
1362                         {
1363                                 struct tomoyo_no_rewrite *ptr =
1364                                         container_of(acl, typeof(*ptr), head);
1365                                 tomoyo_set_string(head,
1366                                                   TOMOYO_KEYWORD_DENY_REWRITE);
1367                                 tomoyo_set_string(head, ptr->pattern->name);
1368                         }
1369                         break;
1370                 default:
1371                         continue;
1372                 }
1373                 tomoyo_set_lf(head);
1374         }
1375         head->r.acl = NULL;
1376         return true;
1377 }
1378
1379 /**
1380  * tomoyo_read_exception - Read exception policy.
1381  *
1382  * @head: Pointer to "struct tomoyo_io_buffer".
1383  *
1384  * Caller holds tomoyo_read_lock().
1385  */
1386 static void tomoyo_read_exception(struct tomoyo_io_buffer *head)
1387 {
1388         if (head->r.eof)
1389                 return;
1390         while (head->r.step < TOMOYO_MAX_POLICY &&
1391                tomoyo_read_policy(head, head->r.step))
1392                 head->r.step++;
1393         if (head->r.step < TOMOYO_MAX_POLICY)
1394                 return;
1395         while (head->r.step < TOMOYO_MAX_POLICY + TOMOYO_MAX_GROUP &&
1396                tomoyo_read_group(head, head->r.step - TOMOYO_MAX_POLICY))
1397                 head->r.step++;
1398         if (head->r.step < TOMOYO_MAX_POLICY + TOMOYO_MAX_GROUP)
1399                 return;
1400         head->r.eof = true;
1401 }
1402
1403 /**
1404  * tomoyo_print_header - Get header line of audit log.
1405  *
1406  * @r: Pointer to "struct tomoyo_request_info".
1407  *
1408  * Returns string representation.
1409  *
1410  * This function uses kmalloc(), so caller must kfree() if this function
1411  * didn't return NULL.
1412  */
1413 static char *tomoyo_print_header(struct tomoyo_request_info *r)
1414 {
1415         struct timeval tv;
1416         const pid_t gpid = task_pid_nr(current);
1417         static const int tomoyo_buffer_len = 4096;
1418         char *buffer = kmalloc(tomoyo_buffer_len, GFP_NOFS);
1419         if (!buffer)
1420                 return NULL;
1421         do_gettimeofday(&tv);
1422         snprintf(buffer, tomoyo_buffer_len - 1,
1423                  "#timestamp=%lu profile=%u mode=%s (global-pid=%u)"
1424                  " task={ pid=%u ppid=%u uid=%u gid=%u euid=%u"
1425                  " egid=%u suid=%u sgid=%u fsuid=%u fsgid=%u }",
1426                  tv.tv_sec, r->profile, tomoyo_mode[r->mode], gpid,
1427                  (pid_t) sys_getpid(), (pid_t) sys_getppid(),
1428                  current_uid(), current_gid(), current_euid(),
1429                  current_egid(), current_suid(), current_sgid(),
1430                  current_fsuid(), current_fsgid());
1431         return buffer;
1432 }
1433
1434 /**
1435  * tomoyo_init_audit_log - Allocate buffer for audit logs.
1436  *
1437  * @len: Required size.
1438  * @r:   Pointer to "struct tomoyo_request_info".
1439  *
1440  * Returns pointer to allocated memory.
1441  *
1442  * The @len is updated to add the header lines' size on success.
1443  *
1444  * This function uses kzalloc(), so caller must kfree() if this function
1445  * didn't return NULL.
1446  */
1447 static char *tomoyo_init_audit_log(int *len, struct tomoyo_request_info *r)
1448 {
1449         char *buf = NULL;
1450         const char *header;
1451         const char *domainname;
1452         if (!r->domain)
1453                 r->domain = tomoyo_domain();
1454         domainname = r->domain->domainname->name;
1455         header = tomoyo_print_header(r);
1456         if (!header)
1457                 return NULL;
1458         *len += strlen(domainname) + strlen(header) + 10;
1459         buf = kzalloc(*len, GFP_NOFS);
1460         if (buf)
1461                 snprintf(buf, (*len) - 1, "%s\n%s\n", header, domainname);
1462         kfree(header);
1463         return buf;
1464 }
1465
1466 /* Wait queue for tomoyo_query_list. */
1467 static DECLARE_WAIT_QUEUE_HEAD(tomoyo_query_wait);
1468
1469 /* Lock for manipulating tomoyo_query_list. */
1470 static DEFINE_SPINLOCK(tomoyo_query_list_lock);
1471
1472 /* Structure for query. */
1473 struct tomoyo_query {
1474         struct list_head list;
1475         char *query;
1476         int query_len;
1477         unsigned int serial;
1478         int timer;
1479         int answer;
1480 };
1481
1482 /* The list for "struct tomoyo_query". */
1483 static LIST_HEAD(tomoyo_query_list);
1484
1485 /*
1486  * Number of "struct file" referring /sys/kernel/security/tomoyo/query
1487  * interface.
1488  */
1489 static atomic_t tomoyo_query_observers = ATOMIC_INIT(0);
1490
1491 /**
1492  * tomoyo_supervisor - Ask for the supervisor's decision.
1493  *
1494  * @r:       Pointer to "struct tomoyo_request_info".
1495  * @fmt:     The printf()'s format string, followed by parameters.
1496  *
1497  * Returns 0 if the supervisor decided to permit the access request which
1498  * violated the policy in enforcing mode, TOMOYO_RETRY_REQUEST if the
1499  * supervisor decided to retry the access request which violated the policy in
1500  * enforcing mode, 0 if it is not in enforcing mode, -EPERM otherwise.
1501  */
1502 int tomoyo_supervisor(struct tomoyo_request_info *r, const char *fmt, ...)
1503 {
1504         va_list args;
1505         int error = -EPERM;
1506         int pos;
1507         int len;
1508         static unsigned int tomoyo_serial;
1509         struct tomoyo_query *entry = NULL;
1510         bool quota_exceeded = false;
1511         char *header;
1512         switch (r->mode) {
1513                 char *buffer;
1514         case TOMOYO_CONFIG_LEARNING:
1515                 if (!tomoyo_domain_quota_is_ok(r))
1516                         return 0;
1517                 va_start(args, fmt);
1518                 len = vsnprintf((char *) &pos, sizeof(pos) - 1, fmt, args) + 4;
1519                 va_end(args);
1520                 buffer = kmalloc(len, GFP_NOFS);
1521                 if (!buffer)
1522                         return 0;
1523                 va_start(args, fmt);
1524                 vsnprintf(buffer, len - 1, fmt, args);
1525                 va_end(args);
1526                 tomoyo_normalize_line(buffer);
1527                 tomoyo_write_domain2(buffer, r->domain, false);
1528                 kfree(buffer);
1529                 /* fall through */
1530         case TOMOYO_CONFIG_PERMISSIVE:
1531                 return 0;
1532         }
1533         if (!r->domain)
1534                 r->domain = tomoyo_domain();
1535         if (!atomic_read(&tomoyo_query_observers))
1536                 return -EPERM;
1537         va_start(args, fmt);
1538         len = vsnprintf((char *) &pos, sizeof(pos) - 1, fmt, args) + 32;
1539         va_end(args);
1540         header = tomoyo_init_audit_log(&len, r);
1541         if (!header)
1542                 goto out;
1543         entry = kzalloc(sizeof(*entry), GFP_NOFS);
1544         if (!entry)
1545                 goto out;
1546         entry->query = kzalloc(len, GFP_NOFS);
1547         if (!entry->query)
1548                 goto out;
1549         len = ksize(entry->query);
1550         spin_lock(&tomoyo_query_list_lock);
1551         if (tomoyo_quota_for_query && tomoyo_query_memory_size + len +
1552             sizeof(*entry) >= tomoyo_quota_for_query) {
1553                 quota_exceeded = true;
1554         } else {
1555                 tomoyo_query_memory_size += len + sizeof(*entry);
1556                 entry->serial = tomoyo_serial++;
1557         }
1558         spin_unlock(&tomoyo_query_list_lock);
1559         if (quota_exceeded)
1560                 goto out;
1561         pos = snprintf(entry->query, len - 1, "Q%u-%hu\n%s",
1562                        entry->serial, r->retry, header);
1563         kfree(header);
1564         header = NULL;
1565         va_start(args, fmt);
1566         vsnprintf(entry->query + pos, len - 1 - pos, fmt, args);
1567         entry->query_len = strlen(entry->query) + 1;
1568         va_end(args);
1569         spin_lock(&tomoyo_query_list_lock);
1570         list_add_tail(&entry->list, &tomoyo_query_list);
1571         spin_unlock(&tomoyo_query_list_lock);
1572         /* Give 10 seconds for supervisor's opinion. */
1573         for (entry->timer = 0;
1574              atomic_read(&tomoyo_query_observers) && entry->timer < 100;
1575              entry->timer++) {
1576                 wake_up(&tomoyo_query_wait);
1577                 set_current_state(TASK_INTERRUPTIBLE);
1578                 schedule_timeout(HZ / 10);
1579                 if (entry->answer)
1580                         break;
1581         }
1582         spin_lock(&tomoyo_query_list_lock);
1583         list_del(&entry->list);
1584         tomoyo_query_memory_size -= len + sizeof(*entry);
1585         spin_unlock(&tomoyo_query_list_lock);
1586         switch (entry->answer) {
1587         case 3: /* Asked to retry by administrator. */
1588                 error = TOMOYO_RETRY_REQUEST;
1589                 r->retry++;
1590                 break;
1591         case 1:
1592                 /* Granted by administrator. */
1593                 error = 0;
1594                 break;
1595         case 0:
1596                 /* Timed out. */
1597                 break;
1598         default:
1599                 /* Rejected by administrator. */
1600                 break;
1601         }
1602  out:
1603         if (entry)
1604                 kfree(entry->query);
1605         kfree(entry);
1606         kfree(header);
1607         return error;
1608 }
1609
1610 /**
1611  * tomoyo_poll_query - poll() for /sys/kernel/security/tomoyo/query.
1612  *
1613  * @file: Pointer to "struct file".
1614  * @wait: Pointer to "poll_table".
1615  *
1616  * Returns POLLIN | POLLRDNORM when ready to read, 0 otherwise.
1617  *
1618  * Waits for access requests which violated policy in enforcing mode.
1619  */
1620 static int tomoyo_poll_query(struct file *file, poll_table *wait)
1621 {
1622         struct list_head *tmp;
1623         bool found = false;
1624         u8 i;
1625         for (i = 0; i < 2; i++) {
1626                 spin_lock(&tomoyo_query_list_lock);
1627                 list_for_each(tmp, &tomoyo_query_list) {
1628                         struct tomoyo_query *ptr =
1629                                 list_entry(tmp, typeof(*ptr), list);
1630                         if (ptr->answer)
1631                                 continue;
1632                         found = true;
1633                         break;
1634                 }
1635                 spin_unlock(&tomoyo_query_list_lock);
1636                 if (found)
1637                         return POLLIN | POLLRDNORM;
1638                 if (i)
1639                         break;
1640                 poll_wait(file, &tomoyo_query_wait, wait);
1641         }
1642         return 0;
1643 }
1644
1645 /**
1646  * tomoyo_read_query - Read access requests which violated policy in enforcing mode.
1647  *
1648  * @head: Pointer to "struct tomoyo_io_buffer".
1649  */
1650 static void tomoyo_read_query(struct tomoyo_io_buffer *head)
1651 {
1652         struct list_head *tmp;
1653         int pos = 0;
1654         int len = 0;
1655         char *buf;
1656         if (head->r.w_pos)
1657                 return;
1658         if (head->read_buf) {
1659                 kfree(head->read_buf);
1660                 head->read_buf = NULL;
1661         }
1662         spin_lock(&tomoyo_query_list_lock);
1663         list_for_each(tmp, &tomoyo_query_list) {
1664                 struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
1665                 if (ptr->answer)
1666                         continue;
1667                 if (pos++ != head->r.query_index)
1668                         continue;
1669                 len = ptr->query_len;
1670                 break;
1671         }
1672         spin_unlock(&tomoyo_query_list_lock);
1673         if (!len) {
1674                 head->r.query_index = 0;
1675                 return;
1676         }
1677         buf = kzalloc(len, GFP_NOFS);
1678         if (!buf)
1679                 return;
1680         pos = 0;
1681         spin_lock(&tomoyo_query_list_lock);
1682         list_for_each(tmp, &tomoyo_query_list) {
1683                 struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
1684                 if (ptr->answer)
1685                         continue;
1686                 if (pos++ != head->r.query_index)
1687                         continue;
1688                 /*
1689                  * Some query can be skipped because tomoyo_query_list
1690                  * can change, but I don't care.
1691                  */
1692                 if (len == ptr->query_len)
1693                         memmove(buf, ptr->query, len);
1694                 break;
1695         }
1696         spin_unlock(&tomoyo_query_list_lock);
1697         if (buf[0]) {
1698                 head->read_buf = buf;
1699                 head->r.w[head->r.w_pos++] = buf;
1700                 head->r.query_index++;
1701         } else {
1702                 kfree(buf);
1703         }
1704 }
1705
1706 /**
1707  * tomoyo_write_answer - Write the supervisor's decision.
1708  *
1709  * @head: Pointer to "struct tomoyo_io_buffer".
1710  *
1711  * Returns 0 on success, -EINVAL otherwise.
1712  */
1713 static int tomoyo_write_answer(struct tomoyo_io_buffer *head)
1714 {
1715         char *data = head->write_buf;
1716         struct list_head *tmp;
1717         unsigned int serial;
1718         unsigned int answer;
1719         spin_lock(&tomoyo_query_list_lock);
1720         list_for_each(tmp, &tomoyo_query_list) {
1721                 struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
1722                 ptr->timer = 0;
1723         }
1724         spin_unlock(&tomoyo_query_list_lock);
1725         if (sscanf(data, "A%u=%u", &serial, &answer) != 2)
1726                 return -EINVAL;
1727         spin_lock(&tomoyo_query_list_lock);
1728         list_for_each(tmp, &tomoyo_query_list) {
1729                 struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
1730                 if (ptr->serial != serial)
1731                         continue;
1732                 if (!ptr->answer)
1733                         ptr->answer = answer;
1734                 break;
1735         }
1736         spin_unlock(&tomoyo_query_list_lock);
1737         return 0;
1738 }
1739
1740 /**
1741  * tomoyo_read_version: Get version.
1742  *
1743  * @head: Pointer to "struct tomoyo_io_buffer".
1744  *
1745  * Returns version information.
1746  */
1747 static void tomoyo_read_version(struct tomoyo_io_buffer *head)
1748 {
1749         if (!head->r.eof) {
1750                 tomoyo_io_printf(head, "2.3.0");
1751                 head->r.eof = true;
1752         }
1753 }
1754
1755 /**
1756  * tomoyo_read_self_domain - Get the current process's domainname.
1757  *
1758  * @head: Pointer to "struct tomoyo_io_buffer".
1759  *
1760  * Returns the current process's domainname.
1761  */
1762 static void tomoyo_read_self_domain(struct tomoyo_io_buffer *head)
1763 {
1764         if (!head->r.eof) {
1765                 /*
1766                  * tomoyo_domain()->domainname != NULL
1767                  * because every process belongs to a domain and
1768                  * the domain's name cannot be NULL.
1769                  */
1770                 tomoyo_io_printf(head, "%s", tomoyo_domain()->domainname->name);
1771                 head->r.eof = true;
1772         }
1773 }
1774
1775 /**
1776  * tomoyo_open_control - open() for /sys/kernel/security/tomoyo/ interface.
1777  *
1778  * @type: Type of interface.
1779  * @file: Pointer to "struct file".
1780  *
1781  * Associates policy handler and returns 0 on success, -ENOMEM otherwise.
1782  *
1783  * Caller acquires tomoyo_read_lock().
1784  */
1785 int tomoyo_open_control(const u8 type, struct file *file)
1786 {
1787         struct tomoyo_io_buffer *head = kzalloc(sizeof(*head), GFP_NOFS);
1788
1789         if (!head)
1790                 return -ENOMEM;
1791         mutex_init(&head->io_sem);
1792         head->type = type;
1793         switch (type) {
1794         case TOMOYO_DOMAINPOLICY:
1795                 /* /sys/kernel/security/tomoyo/domain_policy */
1796                 head->write = tomoyo_write_domain;
1797                 head->read = tomoyo_read_domain;
1798                 break;
1799         case TOMOYO_EXCEPTIONPOLICY:
1800                 /* /sys/kernel/security/tomoyo/exception_policy */
1801                 head->write = tomoyo_write_exception;
1802                 head->read = tomoyo_read_exception;
1803                 break;
1804         case TOMOYO_SELFDOMAIN:
1805                 /* /sys/kernel/security/tomoyo/self_domain */
1806                 head->read = tomoyo_read_self_domain;
1807                 break;
1808         case TOMOYO_DOMAIN_STATUS:
1809                 /* /sys/kernel/security/tomoyo/.domain_status */
1810                 head->write = tomoyo_write_domain_profile;
1811                 head->read = tomoyo_read_domain_profile;
1812                 break;
1813         case TOMOYO_PROCESS_STATUS:
1814                 /* /sys/kernel/security/tomoyo/.process_status */
1815                 head->write = tomoyo_write_pid;
1816                 head->read = tomoyo_read_pid;
1817                 break;
1818         case TOMOYO_VERSION:
1819                 /* /sys/kernel/security/tomoyo/version */
1820                 head->read = tomoyo_read_version;
1821                 head->readbuf_size = 128;
1822                 break;
1823         case TOMOYO_MEMINFO:
1824                 /* /sys/kernel/security/tomoyo/meminfo */
1825                 head->write = tomoyo_write_memory_quota;
1826                 head->read = tomoyo_read_memory_counter;
1827                 head->readbuf_size = 512;
1828                 break;
1829         case TOMOYO_PROFILE:
1830                 /* /sys/kernel/security/tomoyo/profile */
1831                 head->write = tomoyo_write_profile;
1832                 head->read = tomoyo_read_profile;
1833                 break;
1834         case TOMOYO_QUERY: /* /sys/kernel/security/tomoyo/query */
1835                 head->poll = tomoyo_poll_query;
1836                 head->write = tomoyo_write_answer;
1837                 head->read = tomoyo_read_query;
1838                 break;
1839         case TOMOYO_MANAGER:
1840                 /* /sys/kernel/security/tomoyo/manager */
1841                 head->write = tomoyo_write_manager;
1842                 head->read = tomoyo_read_manager;
1843                 break;
1844         }
1845         if (!(file->f_mode & FMODE_READ)) {
1846                 /*
1847                  * No need to allocate read_buf since it is not opened
1848                  * for reading.
1849                  */
1850                 head->read = NULL;
1851                 head->poll = NULL;
1852         } else if (!head->poll) {
1853                 /* Don't allocate read_buf for poll() access. */
1854                 if (!head->readbuf_size)
1855                         head->readbuf_size = 4096 * 2;
1856                 head->read_buf = kzalloc(head->readbuf_size, GFP_NOFS);
1857                 if (!head->read_buf) {
1858                         kfree(head);
1859                         return -ENOMEM;
1860                 }
1861         }
1862         if (!(file->f_mode & FMODE_WRITE)) {
1863                 /*
1864                  * No need to allocate write_buf since it is not opened
1865                  * for writing.
1866                  */
1867                 head->write = NULL;
1868         } else if (head->write) {
1869                 head->writebuf_size = 4096 * 2;
1870                 head->write_buf = kzalloc(head->writebuf_size, GFP_NOFS);
1871                 if (!head->write_buf) {
1872                         kfree(head->read_buf);
1873                         kfree(head);
1874                         return -ENOMEM;
1875                 }
1876         }
1877         if (type != TOMOYO_QUERY)
1878                 head->reader_idx = tomoyo_read_lock();
1879         file->private_data = head;
1880         /*
1881          * Call the handler now if the file is
1882          * /sys/kernel/security/tomoyo/self_domain
1883          * so that the user can use
1884          * cat < /sys/kernel/security/tomoyo/self_domain"
1885          * to know the current process's domainname.
1886          */
1887         if (type == TOMOYO_SELFDOMAIN)
1888                 tomoyo_read_control(file, NULL, 0);
1889         /*
1890          * If the file is /sys/kernel/security/tomoyo/query , increment the
1891          * observer counter.
1892          * The obserber counter is used by tomoyo_supervisor() to see if
1893          * there is some process monitoring /sys/kernel/security/tomoyo/query.
1894          */
1895         else if (type == TOMOYO_QUERY)
1896                 atomic_inc(&tomoyo_query_observers);
1897         return 0;
1898 }
1899
1900 /**
1901  * tomoyo_poll_control - poll() for /sys/kernel/security/tomoyo/ interface.
1902  *
1903  * @file: Pointer to "struct file".
1904  * @wait: Pointer to "poll_table".
1905  *
1906  * Waits for read readiness.
1907  * /sys/kernel/security/tomoyo/query is handled by /usr/sbin/tomoyo-queryd .
1908  */
1909 int tomoyo_poll_control(struct file *file, poll_table *wait)
1910 {
1911         struct tomoyo_io_buffer *head = file->private_data;
1912         if (!head->poll)
1913                 return -ENOSYS;
1914         return head->poll(file, wait);
1915 }
1916
1917 /**
1918  * tomoyo_read_control - read() for /sys/kernel/security/tomoyo/ interface.
1919  *
1920  * @file:       Pointer to "struct file".
1921  * @buffer:     Poiner to buffer to write to.
1922  * @buffer_len: Size of @buffer.
1923  *
1924  * Returns bytes read on success, negative value otherwise.
1925  *
1926  * Caller holds tomoyo_read_lock().
1927  */
1928 int tomoyo_read_control(struct file *file, char __user *buffer,
1929                         const int buffer_len)
1930 {
1931         int len;
1932         struct tomoyo_io_buffer *head = file->private_data;
1933
1934         if (!head->read)
1935                 return -ENOSYS;
1936         if (mutex_lock_interruptible(&head->io_sem))
1937                 return -EINTR;
1938         head->read_user_buf = buffer;
1939         head->read_user_buf_avail = buffer_len;
1940         if (tomoyo_flush(head))
1941                 /* Call the policy handler. */
1942                 head->read(head);
1943         tomoyo_flush(head);
1944         len = head->read_user_buf - buffer;
1945         mutex_unlock(&head->io_sem);
1946         return len;
1947 }
1948
1949 /**
1950  * tomoyo_write_control - write() for /sys/kernel/security/tomoyo/ interface.
1951  *
1952  * @file:       Pointer to "struct file".
1953  * @buffer:     Pointer to buffer to read from.
1954  * @buffer_len: Size of @buffer.
1955  *
1956  * Returns @buffer_len on success, negative value otherwise.
1957  *
1958  * Caller holds tomoyo_read_lock().
1959  */
1960 int tomoyo_write_control(struct file *file, const char __user *buffer,
1961                          const int buffer_len)
1962 {
1963         struct tomoyo_io_buffer *head = file->private_data;
1964         int error = buffer_len;
1965         int avail_len = buffer_len;
1966         char *cp0 = head->write_buf;
1967
1968         if (!head->write)
1969                 return -ENOSYS;
1970         if (!access_ok(VERIFY_READ, buffer, buffer_len))
1971                 return -EFAULT;
1972         /* Don't allow updating policies by non manager programs. */
1973         if (head->write != tomoyo_write_pid &&
1974             head->write != tomoyo_write_domain && !tomoyo_manager())
1975                 return -EPERM;
1976         if (mutex_lock_interruptible(&head->io_sem))
1977                 return -EINTR;
1978         /* Read a line and dispatch it to the policy handler. */
1979         while (avail_len > 0) {
1980                 char c;
1981                 if (head->write_avail >= head->writebuf_size - 1) {
1982                         error = -ENOMEM;
1983                         break;
1984                 } else if (get_user(c, buffer)) {
1985                         error = -EFAULT;
1986                         break;
1987                 }
1988                 buffer++;
1989                 avail_len--;
1990                 cp0[head->write_avail++] = c;
1991                 if (c != '\n')
1992                         continue;
1993                 cp0[head->write_avail - 1] = '\0';
1994                 head->write_avail = 0;
1995                 tomoyo_normalize_line(cp0);
1996                 head->write(head);
1997         }
1998         mutex_unlock(&head->io_sem);
1999         return error;
2000 }
2001
2002 /**
2003  * tomoyo_close_control - close() for /sys/kernel/security/tomoyo/ interface.
2004  *
2005  * @file: Pointer to "struct file".
2006  *
2007  * Releases memory and returns 0.
2008  *
2009  * Caller looses tomoyo_read_lock().
2010  */
2011 int tomoyo_close_control(struct file *file)
2012 {
2013         struct tomoyo_io_buffer *head = file->private_data;
2014         const bool is_write = !!head->write_buf;
2015
2016         /*
2017          * If the file is /sys/kernel/security/tomoyo/query , decrement the
2018          * observer counter.
2019          */
2020         if (head->type == TOMOYO_QUERY)
2021                 atomic_dec(&tomoyo_query_observers);
2022         else
2023                 tomoyo_read_unlock(head->reader_idx);
2024         /* Release memory used for policy I/O. */
2025         kfree(head->read_buf);
2026         head->read_buf = NULL;
2027         kfree(head->write_buf);
2028         head->write_buf = NULL;
2029         kfree(head);
2030         head = NULL;
2031         file->private_data = NULL;
2032         if (is_write)
2033                 tomoyo_run_gc();
2034         return 0;
2035 }
2036
2037 /**
2038  * tomoyo_check_profile - Check all profiles currently assigned to domains are defined.
2039  */
2040 void tomoyo_check_profile(void)
2041 {
2042         struct tomoyo_domain_info *domain;
2043         const int idx = tomoyo_read_lock();
2044         tomoyo_policy_loaded = true;
2045         /* Check all profiles currently assigned to domains are defined. */
2046         list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
2047                 const u8 profile = domain->profile;
2048                 if (tomoyo_profile_ptr[profile])
2049                         continue;
2050                 panic("Profile %u (used by '%s') not defined.\n",
2051                       profile, domain->domainname->name);
2052         }
2053         tomoyo_read_unlock(idx);
2054         if (tomoyo_profile_version != 20090903)
2055                 panic("Profile version %u is not supported.\n",
2056                       tomoyo_profile_version);
2057         printk(KERN_INFO "TOMOYO: 2.3.0\n");
2058         printk(KERN_INFO "Mandatory Access Control activated.\n");
2059 }