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 /* String table for operation mode. */
  15 const char * const tomoyo_mode[TOMOYO_CONFIG_MAX_MODE] = {
  16         [TOMOYO_CONFIG_DISABLED]   = "disabled",
  17         [TOMOYO_CONFIG_LEARNING]   = "learning",
  18         [TOMOYO_CONFIG_PERMISSIVE] = "permissive",
  19         [TOMOYO_CONFIG_ENFORCING]  = "enforcing"
  20 };
  21
  22 /* String table for /sys/kernel/security/tomoyo/profile */
  23 const char * const tomoyo_mac_keywords[TOMOYO_MAX_MAC_INDEX
  24                                        + TOMOYO_MAX_MAC_CATEGORY_INDEX] = {
  25         [TOMOYO_MAC_FILE_EXECUTE]    = "execute",
  26         [TOMOYO_MAC_FILE_OPEN]       = "open",
  27         [TOMOYO_MAC_FILE_CREATE]     = "create",
  28         [TOMOYO_MAC_FILE_UNLINK]     = "unlink",
  29         [TOMOYO_MAC_FILE_GETATTR]    = "getattr",
  30         [TOMOYO_MAC_FILE_MKDIR]      = "mkdir",
  31         [TOMOYO_MAC_FILE_RMDIR]      = "rmdir",
  32         [TOMOYO_MAC_FILE_MKFIFO]     = "mkfifo",
  33         [TOMOYO_MAC_FILE_MKSOCK]     = "mksock",
  34         [TOMOYO_MAC_FILE_TRUNCATE]   = "truncate",
  35         [TOMOYO_MAC_FILE_SYMLINK]    = "symlink",
  36         [TOMOYO_MAC_FILE_MKBLOCK]    = "mkblock",
  37         [TOMOYO_MAC_FILE_MKCHAR]     = "mkchar",
  38         [TOMOYO_MAC_FILE_LINK]       = "link",
  39         [TOMOYO_MAC_FILE_RENAME]     = "rename",
  40         [TOMOYO_MAC_FILE_CHMOD]      = "chmod",
  41         [TOMOYO_MAC_FILE_CHOWN]      = "chown",
  42         [TOMOYO_MAC_FILE_CHGRP]      = "chgrp",
  43         [TOMOYO_MAC_FILE_IOCTL]      = "ioctl",
  44         [TOMOYO_MAC_FILE_CHROOT]     = "chroot",
  45         [TOMOYO_MAC_FILE_MOUNT]      = "mount",
  46         [TOMOYO_MAC_FILE_UMOUNT]     = "unmount",
  47         [TOMOYO_MAC_FILE_PIVOT_ROOT] = "pivot_root",
  48         [TOMOYO_MAX_MAC_INDEX + TOMOYO_MAC_CATEGORY_FILE] = "file",
  49 };
  50
  51 /* String table for PREFERENCE keyword. */
  52 static const char * const tomoyo_pref_keywords[TOMOYO_MAX_PREF] = {
  53         [TOMOYO_PREF_MAX_AUDIT_LOG]      = "max_audit_log",
  54         [TOMOYO_PREF_MAX_LEARNING_ENTRY] = "max_learning_entry",
  55 };
  56
  57 /* String table for path operation. */
  58 const char * const tomoyo_path_keyword[TOMOYO_MAX_PATH_OPERATION] = {
  59         [TOMOYO_TYPE_EXECUTE]    = "execute",
  60         [TOMOYO_TYPE_READ]       = "read",
  61         [TOMOYO_TYPE_WRITE]      = "write",
  62         [TOMOYO_TYPE_APPEND]     = "append",
  63         [TOMOYO_TYPE_UNLINK]     = "unlink",
  64         [TOMOYO_TYPE_GETATTR]    = "getattr",
  65         [TOMOYO_TYPE_RMDIR]      = "rmdir",
  66         [TOMOYO_TYPE_TRUNCATE]   = "truncate",
  67         [TOMOYO_TYPE_SYMLINK]    = "symlink",
  68         [TOMOYO_TYPE_CHROOT]     = "chroot",
  69         [TOMOYO_TYPE_UMOUNT]     = "unmount",
  70 };
  71
  72 /* String table for categories. */
  73 static const char * const tomoyo_category_keywords
  74 [TOMOYO_MAX_MAC_CATEGORY_INDEX] = {
  75         [TOMOYO_MAC_CATEGORY_FILE]       = "file",
  76 };
  77
  78 /* Permit policy management by non-root user? */
  79 static bool tomoyo_manage_by_non_root;
  80
  81 /* Utility functions. */
  82
  83 /**
  84  * tomoyo_yesno - Return "yes" or "no".
  85  *
  86  * @value: Bool value.
  87  */
  88 const char *tomoyo_yesno(const unsigned int value)
  89 {
  90         return value ? "yes" : "no";
  91 }
  92
  93 /**
  94  * tomoyo_addprintf - strncat()-like-snprintf().
  95  *
  96  * @buffer: Buffer to write to. Must be '\0'-terminated.
  97  * @len:    Size of @buffer.
  98  * @fmt:    The printf()'s format string, followed by parameters.
  99  *
 100  * Returns nothing.
 101  */
 102 static void tomoyo_addprintf(char *buffer, int len, const char *fmt, ...)
 103 {
 104         va_list args;
 105         const int pos = strlen(buffer);
 106         va_start(args, fmt);
 107         vsnprintf(buffer + pos, len - pos - 1, fmt, args);
 108         va_end(args);
 109 }
 110
 111 /**
 112  * tomoyo_flush - Flush queued string to userspace's buffer.
 113  *
 114  * @head:   Pointer to "struct tomoyo_io_buffer".
 115  *
 116  * Returns true if all data was flushed, false otherwise.
 117  */
 118 static bool tomoyo_flush(struct tomoyo_io_buffer *head)
 119 {
 120         while (head->r.w_pos) {
 121                 const char *w = head->r.w[0];
 122                 size_t len = strlen(w);
 123                 if (len) {
 124                         if (len > head->read_user_buf_avail)
 125                                 len = head->read_user_buf_avail;
 126                         if (!len)
 127                                 return false;
 128                         if (copy_to_user(head->read_user_buf, w, len))
 129                                 return false;
 130                         head->read_user_buf_avail -= len;
 131                         head->read_user_buf += len;
 132                         w += len;
 133                 }
 134                 head->r.w[0] = w;
 135                 if (*w)
 136                         return false;
 137                 /* Add '\0' for audit logs and query. */
 138                 if (head->poll) {
 139                         if (!head->read_user_buf_avail ||
 140                             copy_to_user(head->read_user_buf, "", 1))
 141                                 return false;
 142                         head->read_user_buf_avail--;
 143                         head->read_user_buf++;
 144                 }
 145                 head->r.w_pos--;
 146                 for (len = 0; len < head->r.w_pos; len++)
 147                         head->r.w[len] = head->r.w[len + 1];
 148         }
 149         head->r.avail = 0;
 150         return true;
 151 }
 152
 153 /**
 154  * tomoyo_set_string - Queue string to "struct tomoyo_io_buffer" structure.
 155  *
 156  * @head:   Pointer to "struct tomoyo_io_buffer".
 157  * @string: String to print.
 158  *
 159  * Note that @string has to be kept valid until @head is kfree()d.
 160  * This means that char[] allocated on stack memory cannot be passed to
 161  * this function. Use tomoyo_io_printf() for char[] allocated on stack memory.
 162  */
 163 static void tomoyo_set_string(struct tomoyo_io_buffer *head, const char *string)
 164 {
 165         if (head->r.w_pos < TOMOYO_MAX_IO_READ_QUEUE) {
 166                 head->r.w[head->r.w_pos++] = string;
 167                 tomoyo_flush(head);
 168         } else
 169                 WARN_ON(1);
 170 }
 171
 172 /**
 173  * tomoyo_io_printf - printf() to "struct tomoyo_io_buffer" structure.
 174  *
 175  * @head: Pointer to "struct tomoyo_io_buffer".
 176  * @fmt:  The printf()'s format string, followed by parameters.
 177  */
 178 void tomoyo_io_printf(struct tomoyo_io_buffer *head, const char *fmt, ...)
 179 {
 180         va_list args;
 181         size_t len;
 182         size_t pos = head->r.avail;
 183         int size = head->readbuf_size - pos;
 184         if (size <= 0)
 185                 return;
 186         va_start(args, fmt);
 187         len = vsnprintf(head->read_buf + pos, size, fmt, args) + 1;
 188         va_end(args);
 189         if (pos + len >= head->readbuf_size) {
 190                 WARN_ON(1);
 191                 return;
 192         }
 193         head->r.avail += len;
 194         tomoyo_set_string(head, head->read_buf + pos);
 195 }
 196
 197 /**
 198  * tomoyo_set_space - Put a space to "struct tomoyo_io_buffer" structure.
 199  *
 200  * @head: Pointer to "struct tomoyo_io_buffer".
 201  *
 202  * Returns nothing.
 203  */
 204 static void tomoyo_set_space(struct tomoyo_io_buffer *head)
 205 {
 206         tomoyo_set_string(head, " ");
 207 }
 208
 209 /**
 210  * tomoyo_set_lf - Put a line feed to "struct tomoyo_io_buffer" structure.
 211  *
 212  * @head: Pointer to "struct tomoyo_io_buffer".
 213  *
 214  * Returns nothing.
 215  */
 216 static bool tomoyo_set_lf(struct tomoyo_io_buffer *head)
 217 {
 218         tomoyo_set_string(head, "\n");
 219         return !head->r.w_pos;
 220 }
 221
 222 /**
 223  * tomoyo_set_slash - Put a shash to "struct tomoyo_io_buffer" structure.
 224  *
 225  * @head: Pointer to "struct tomoyo_io_buffer".
 226  *
 227  * Returns nothing.
 228  */
 229 static void tomoyo_set_slash(struct tomoyo_io_buffer *head)
 230 {
 231         tomoyo_set_string(head, "/");
 232 }
 233
 234 /* List of namespaces. */
 235 LIST_HEAD(tomoyo_namespace_list);
 236 /* True if namespace other than tomoyo_kernel_namespace is defined. */
 237 static bool tomoyo_namespace_enabled;
 238
 239 /**
 240  * tomoyo_init_policy_namespace - Initialize namespace.
 241  *
 242  * @ns: Pointer to "struct tomoyo_policy_namespace".
 243  *
 244  * Returns nothing.
 245  */
 246 void tomoyo_init_policy_namespace(struct tomoyo_policy_namespace *ns)
 247 {
 248         unsigned int idx;
 249         for (idx = 0; idx < TOMOYO_MAX_ACL_GROUPS; idx++)
 250                 INIT_LIST_HEAD(&ns->acl_group[idx]);
 251         for (idx = 0; idx < TOMOYO_MAX_GROUP; idx++)
 252                 INIT_LIST_HEAD(&ns->group_list[idx]);
 253         for (idx = 0; idx < TOMOYO_MAX_POLICY; idx++)
 254                 INIT_LIST_HEAD(&ns->policy_list[idx]);
 255         ns->profile_version = 20100903;
 256         tomoyo_namespace_enabled = !list_empty(&tomoyo_namespace_list);
 257         list_add_tail_rcu(&ns->namespace_list, &tomoyo_namespace_list);
 258 }
 259
 260 /**
 261  * tomoyo_print_namespace - Print namespace header.
 262  *
 263  * @head: Pointer to "struct tomoyo_io_buffer".
 264  *
 265  * Returns nothing.
 266  */
 267 static void tomoyo_print_namespace(struct tomoyo_io_buffer *head)
 268 {
 269         if (!tomoyo_namespace_enabled)
 270                 return;
 271         tomoyo_set_string(head,
 272                           container_of(head->r.ns,
 273                                        struct tomoyo_policy_namespace,
 274                                        namespace_list)->name);
 275         tomoyo_set_space(head);
 276 }
 277
 278 /**
 279  * tomoyo_print_name_union - Print a tomoyo_name_union.
 280  *
 281  * @head: Pointer to "struct tomoyo_io_buffer".
 282  * @ptr:  Pointer to "struct tomoyo_name_union".
 283  */
 284 static void tomoyo_print_name_union(struct tomoyo_io_buffer *head,
 285                                     const struct tomoyo_name_union *ptr)
 286 {
 287         tomoyo_set_space(head);
 288         if (ptr->group) {
 289                 tomoyo_set_string(head, "@");
 290                 tomoyo_set_string(head, ptr->group->group_name->name);
 291         } else {
 292                 tomoyo_set_string(head, ptr->filename->name);
 293         }
 294 }
 295
 296 /**
 297  * tomoyo_print_number_union - Print a tomoyo_number_union.
 298  *
 299  * @head:       Pointer to "struct tomoyo_io_buffer".
 300  * @ptr:        Pointer to "struct tomoyo_number_union".
 301  */
 302 static void tomoyo_print_number_union(struct tomoyo_io_buffer *head,
 303                                       const struct tomoyo_number_union *ptr)
 304 {
 305         tomoyo_set_space(head);
 306         if (ptr->group) {
 307                 tomoyo_set_string(head, "@");
 308                 tomoyo_set_string(head, ptr->group->group_name->name);
 309         } else {
 310                 int i;
 311                 unsigned long min = ptr->values[0];
 312                 const unsigned long max = ptr->values[1];
 313                 u8 min_type = ptr->value_type[0];
 314                 const u8 max_type = ptr->value_type[1];
 315                 char buffer[128];
 316                 buffer[0] = '\0';
 317                 for (i = 0; i < 2; i++) {
 318                         switch (min_type) {
 319                         case TOMOYO_VALUE_TYPE_HEXADECIMAL:
 320                                 tomoyo_addprintf(buffer, sizeof(buffer),
 321                                                  "0x%lX", min);
 322                                 break;
 323                         case TOMOYO_VALUE_TYPE_OCTAL:
 324                                 tomoyo_addprintf(buffer, sizeof(buffer),
 325                                                  "0%lo", min);
 326                                 break;
 327                         default:
 328                                 tomoyo_addprintf(buffer, sizeof(buffer),
 329                                                  "%lu", min);
 330                                 break;
 331                         }
 332                         if (min == max && min_type == max_type)
 333                                 break;
 334                         tomoyo_addprintf(buffer, sizeof(buffer), "-");
 335                         min_type = max_type;
 336                         min = max;
 337                 }
 338                 tomoyo_io_printf(head, "%s", buffer);
 339         }
 340 }
 341
 342 /**
 343  * tomoyo_assign_profile - Create a new profile.
 344  *
 345  * @ns:      Pointer to "struct tomoyo_policy_namespace".
 346  * @profile: Profile number to create.
 347  *
 348  * Returns pointer to "struct tomoyo_profile" on success, NULL otherwise.
 349  */
 350 static struct tomoyo_profile *tomoyo_assign_profile
 351 (struct tomoyo_policy_namespace *ns, const unsigned int profile)
 352 {
 353         struct tomoyo_profile *ptr;
 354         struct tomoyo_profile *entry;
 355         if (profile >= TOMOYO_MAX_PROFILES)
 356                 return NULL;
 357         ptr = ns->profile_ptr[profile];
 358         if (ptr)
 359                 return ptr;
 360         entry = kzalloc(sizeof(*entry), GFP_NOFS);
 361         if (mutex_lock_interruptible(&tomoyo_policy_lock))
 362                 goto out;
 363         ptr = ns->profile_ptr[profile];
 364         if (!ptr && tomoyo_memory_ok(entry)) {
 365                 ptr = entry;
 366                 ptr->default_config = TOMOYO_CONFIG_DISABLED |
 367                         TOMOYO_CONFIG_WANT_GRANT_LOG |
 368                         TOMOYO_CONFIG_WANT_REJECT_LOG;
 369                 memset(ptr->config, TOMOYO_CONFIG_USE_DEFAULT,
 370                        sizeof(ptr->config));
 371                 ptr->pref[TOMOYO_PREF_MAX_AUDIT_LOG] = 1024;
 372                 ptr->pref[TOMOYO_PREF_MAX_LEARNING_ENTRY] = 2048;
 373                 mb(); /* Avoid out-of-order execution. */
 374                 ns->profile_ptr[profile] = ptr;
 375                 entry = NULL;
 376         }
 377         mutex_unlock(&tomoyo_policy_lock);
 378  out:
 379         kfree(entry);
 380         return ptr;
 381 }
 382
 383 /**
 384  * tomoyo_profile - Find a profile.
 385  *
 386  * @ns:      Pointer to "struct tomoyo_policy_namespace".
 387  * @profile: Profile number to find.
 388  *
 389  * Returns pointer to "struct tomoyo_profile".
 390  */
 391 struct tomoyo_profile *tomoyo_profile(const struct tomoyo_policy_namespace *ns,
 392                                       const u8 profile)
 393 {
 394         static struct tomoyo_profile tomoyo_null_profile;
 395         struct tomoyo_profile *ptr = ns->profile_ptr[profile];
 396         if (!ptr)
 397                 ptr = &tomoyo_null_profile;
 398         return ptr;
 399 }
 400
 401 /**
 402  * tomoyo_find_yesno - Find values for specified keyword.
 403  *
 404  * @string: String to check.
 405  * @find:   Name of keyword.
 406  *
 407  * Returns 1 if "@find=yes" was found, 0 if "@find=no" was found, -1 otherwise.
 408  */
 409 static s8 tomoyo_find_yesno(const char *string, const char *find)
 410 {
 411         const char *cp = strstr(string, find);
 412         if (cp) {
 413                 cp += strlen(find);
 414                 if (!strncmp(cp, "=yes", 4))
 415                         return 1;
 416                 else if (!strncmp(cp, "=no", 3))
 417                         return 0;
 418         }
 419         return -1;
 420 }
 421
 422 /**
 423  * tomoyo_set_uint - Set value for specified preference.
 424  *
 425  * @i:      Pointer to "unsigned int".
 426  * @string: String to check.
 427  * @find:   Name of keyword.
 428  *
 429  * Returns nothing.
 430  */
 431 static void tomoyo_set_uint(unsigned int *i, const char *string,
 432                             const char *find)
 433 {
 434         const char *cp = strstr(string, find);
 435         if (cp)
 436                 sscanf(cp + strlen(find), "=%u", i);
 437 }
 438
 439 /**
 440  * tomoyo_set_mode - Set mode for specified profile.
 441  *
 442  * @name:    Name of functionality.
 443  * @value:   Mode for @name.
 444  * @profile: Pointer to "struct tomoyo_profile".
 445  *
 446  * Returns 0 on success, negative value otherwise.
 447  */
 448 static int tomoyo_set_mode(char *name, const char *value,
 449                            struct tomoyo_profile *profile)
 450 {
 451         u8 i;
 452         u8 config;
 453         if (!strcmp(name, "CONFIG")) {
 454                 i = TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX;
 455                 config = profile->default_config;
 456         } else if (tomoyo_str_starts(&name, "CONFIG::")) {
 457                 config = 0;
 458                 for (i = 0; i < TOMOYO_MAX_MAC_INDEX
 459                              + TOMOYO_MAX_MAC_CATEGORY_INDEX; i++) {
 460                         int len = 0;
 461                         if (i < TOMOYO_MAX_MAC_INDEX) {
 462                                 const u8 c = tomoyo_index2category[i];
 463                                 const char *category =
 464                                         tomoyo_category_keywords[c];
 465                                 len = strlen(category);
 466                                 if (strncmp(name, category, len) ||
 467                                     name[len++] != ':' || name[len++] != ':')
 468                                         continue;
 469                         }
 470                         if (strcmp(name + len, tomoyo_mac_keywords[i]))
 471                                 continue;
 472                         config = profile->config[i];
 473                         break;
 474                 }
 475                 if (i == TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX)
 476                         return -EINVAL;
 477         } else {
 478                 return -EINVAL;
 479         }
 480         if (strstr(value, "use_default")) {
 481                 config = TOMOYO_CONFIG_USE_DEFAULT;
 482         } else {
 483                 u8 mode;
 484                 for (mode = 0; mode < 4; mode++)
 485                         if (strstr(value, tomoyo_mode[mode]))
 486                                 /*
 487                                  * Update lower 3 bits in order to distinguish
 488                                  * 'config' from 'TOMOYO_CONFIG_USE_DEAFULT'.
 489                                  */
 490                                 config = (config & ~7) | mode;
 491                 if (config != TOMOYO_CONFIG_USE_DEFAULT) {
 492                         switch (tomoyo_find_yesno(value, "grant_log")) {
 493                         case 1:
 494                                 config |= TOMOYO_CONFIG_WANT_GRANT_LOG;
 495                                 break;
 496                         case 0:
 497                                 config &= ~TOMOYO_CONFIG_WANT_GRANT_LOG;
 498                                 break;
 499                         }
 500                         switch (tomoyo_find_yesno(value, "reject_log")) {
 501                         case 1:
 502                                 config |= TOMOYO_CONFIG_WANT_REJECT_LOG;
 503                                 break;
 504                         case 0:
 505                                 config &= ~TOMOYO_CONFIG_WANT_REJECT_LOG;
 506                                 break;
 507                         }
 508                 }
 509         }
 510         if (i < TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX)
 511                 profile->config[i] = config;
 512         else if (config != TOMOYO_CONFIG_USE_DEFAULT)
 513                 profile->default_config = config;
 514         return 0;
 515 }
 516
 517 /**
 518  * tomoyo_write_profile - Write profile table.
 519  *
 520  * @head: Pointer to "struct tomoyo_io_buffer".
 521  *
 522  * Returns 0 on success, negative value otherwise.
 523  */
 524 static int tomoyo_write_profile(struct tomoyo_io_buffer *head)
 525 {
 526         char *data = head->write_buf;
 527         unsigned int i;
 528         char *cp;
 529         struct tomoyo_profile *profile;
 530         if (sscanf(data, "PROFILE_VERSION=%u", &head->w.ns->profile_version)
 531             == 1)
 532                 return 0;
 533         i = simple_strtoul(data, &cp, 10);
 534         if (*cp != '-')
 535                 return -EINVAL;
 536         data = cp + 1;
 537         profile = tomoyo_assign_profile(head->w.ns, i);
 538         if (!profile)
 539                 return -EINVAL;
 540         cp = strchr(data, '=');
 541         if (!cp)
 542                 return -EINVAL;
 543         *cp++ = '\0';
 544         if (!strcmp(data, "COMMENT")) {
 545                 static DEFINE_SPINLOCK(lock);
 546                 const struct tomoyo_path_info *new_comment
 547                         = tomoyo_get_name(cp);
 548                 const struct tomoyo_path_info *old_comment;
 549                 if (!new_comment)
 550                         return -ENOMEM;
 551                 spin_lock(&lock);
 552                 old_comment = profile->comment;
 553                 profile->comment = new_comment;
 554                 spin_unlock(&lock);
 555                 tomoyo_put_name(old_comment);
 556                 return 0;
 557         }
 558         if (!strcmp(data, "PREFERENCE")) {
 559                 for (i = 0; i < TOMOYO_MAX_PREF; i++)
 560                         tomoyo_set_uint(&profile->pref[i], cp,
 561                                         tomoyo_pref_keywords[i]);
 562                 return 0;
 563         }
 564         return tomoyo_set_mode(data, cp, profile);
 565 }
 566
 567 /**
 568  * tomoyo_print_config - Print mode for specified functionality.
 569  *
 570  * @head:   Pointer to "struct tomoyo_io_buffer".
 571  * @config: Mode for that functionality.
 572  *
 573  * Returns nothing.
 574  *
 575  * Caller prints functionality's name.
 576  */
 577 static void tomoyo_print_config(struct tomoyo_io_buffer *head, const u8 config)
 578 {
 579         tomoyo_io_printf(head, "={ mode=%s grant_log=%s reject_log=%s }\n",
 580                          tomoyo_mode[config & 3],
 581                          tomoyo_yesno(config & TOMOYO_CONFIG_WANT_GRANT_LOG),
 582                          tomoyo_yesno(config & TOMOYO_CONFIG_WANT_REJECT_LOG));
 583 }
 584
 585 /**
 586  * tomoyo_read_profile - Read profile table.
 587  *
 588  * @head: Pointer to "struct tomoyo_io_buffer".
 589  *
 590  * Returns nothing.
 591  */
 592 static void tomoyo_read_profile(struct tomoyo_io_buffer *head)
 593 {
 594         u8 index;
 595         struct tomoyo_policy_namespace *ns =
 596                 container_of(head->r.ns, typeof(*ns), namespace_list);
 597         const struct tomoyo_profile *profile;
 598         if (head->r.eof)
 599                 return;
 600  next:
 601         index = head->r.index;
 602         profile = ns->profile_ptr[index];
 603         switch (head->r.step) {
 604         case 0:
 605                 tomoyo_print_namespace(head);
 606                 tomoyo_io_printf(head, "PROFILE_VERSION=%u\n",
 607                                  ns->profile_version);
 608                 head->r.step++;
 609                 break;
 610         case 1:
 611                 for ( ; head->r.index < TOMOYO_MAX_PROFILES;
 612                       head->r.index++)
 613                         if (ns->profile_ptr[head->r.index])
 614                                 break;
 615                 if (head->r.index == TOMOYO_MAX_PROFILES)
 616                         return;
 617                 head->r.step++;
 618                 break;
 619         case 2:
 620                 {
 621                         u8 i;
 622                         const struct tomoyo_path_info *comment =
 623                                 profile->comment;
 624                         tomoyo_print_namespace(head);
 625                         tomoyo_io_printf(head, "%u-COMMENT=", index);
 626                         tomoyo_set_string(head, comment ? comment->name : "");
 627                         tomoyo_set_lf(head);
 628                         tomoyo_io_printf(head, "%u-PREFERENCE={ ", index);
 629                         for (i = 0; i < TOMOYO_MAX_PREF; i++)
 630                                 tomoyo_io_printf(head, "%s=%u ",
 631                                                  tomoyo_pref_keywords[i],
 632                                                  profile->pref[i]);
 633                         tomoyo_set_string(head, "}\n");
 634                         head->r.step++;
 635                 }
 636                 break;
 637         case 3:
 638                 {
 639                         tomoyo_print_namespace(head);
 640                         tomoyo_io_printf(head, "%u-%s", index, "CONFIG");
 641                         tomoyo_print_config(head, profile->default_config);
 642                         head->r.bit = 0;
 643                         head->r.step++;
 644                 }
 645                 break;
 646         case 4:
 647                 for ( ; head->r.bit < TOMOYO_MAX_MAC_INDEX
 648                               + TOMOYO_MAX_MAC_CATEGORY_INDEX; head->r.bit++) {
 649                         const u8 i = head->r.bit;
 650                         const u8 config = profile->config[i];
 651                         if (config == TOMOYO_CONFIG_USE_DEFAULT)
 652                                 continue;
 653                         tomoyo_print_namespace(head);
 654                         if (i < TOMOYO_MAX_MAC_INDEX)
 655                                 tomoyo_io_printf(head, "%u-CONFIG::%s::%s",
 656                                                  index,
 657                                                  tomoyo_category_keywords
 658                                                  [tomoyo_index2category[i]],
 659                                                  tomoyo_mac_keywords[i]);
 660                         else
 661                                 tomoyo_io_printf(head, "%u-CONFIG::%s", index,
 662                                                  tomoyo_mac_keywords[i]);
 663                         tomoyo_print_config(head, config);
 664                         head->r.bit++;
 665                         break;
 666                 }
 667                 if (head->r.bit == TOMOYO_MAX_MAC_INDEX
 668                     + TOMOYO_MAX_MAC_CATEGORY_INDEX) {
 669                         head->r.index++;
 670                         head->r.step = 1;
 671                 }
 672                 break;
 673         }
 674         if (tomoyo_flush(head))
 675                 goto next;
 676 }
 677
 678 static bool tomoyo_same_manager(const struct tomoyo_acl_head *a,
 679                                 const struct tomoyo_acl_head *b)
 680 {
 681         return container_of(a, struct tomoyo_manager, head)->manager ==
 682                 container_of(b, struct tomoyo_manager, head)->manager;
 683 }
 684
 685 /**
 686  * tomoyo_update_manager_entry - Add a manager entry.
 687  *
 688  * @manager:   The path to manager or the domainnamme.
 689  * @is_delete: True if it is a delete request.
 690  *
 691  * Returns 0 on success, negative value otherwise.
 692  *
 693  * Caller holds tomoyo_read_lock().
 694  */
 695 static int tomoyo_update_manager_entry(const char *manager,
 696                                        const bool is_delete)
 697 {
 698         struct tomoyo_manager e = { };
 699         struct tomoyo_acl_param param = {
 700                 /* .ns = &tomoyo_kernel_namespace, */
 701                 .is_delete = is_delete,
 702                 .list = &tomoyo_kernel_namespace.
 703                 policy_list[TOMOYO_ID_MANAGER],
 704         };
 705         int error = is_delete ? -ENOENT : -ENOMEM;
 706         if (tomoyo_domain_def(manager)) {
 707                 if (!tomoyo_correct_domain(manager))
 708                         return -EINVAL;
 709                 e.is_domain = true;
 710         } else {
 711                 if (!tomoyo_correct_path(manager))
 712                         return -EINVAL;
 713         }
 714         e.manager = tomoyo_get_name(manager);
 715         if (e.manager) {
 716                 error = tomoyo_update_policy(&e.head, sizeof(e), &param,
 717                                              tomoyo_same_manager);
 718                 tomoyo_put_name(e.manager);
 719         }
 720         return error;
 721 }
 722
 723 /**
 724  * tomoyo_write_manager - Write manager policy.
 725  *
 726  * @head: Pointer to "struct tomoyo_io_buffer".
 727  *
 728  * Returns 0 on success, negative value otherwise.
 729  *
 730  * Caller holds tomoyo_read_lock().
 731  */
 732 static int tomoyo_write_manager(struct tomoyo_io_buffer *head)
 733 {
 734         char *data = head->write_buf;
 735
 736         if (!strcmp(data, "manage_by_non_root")) {
 737                 tomoyo_manage_by_non_root = !head->w.is_delete;
 738                 return 0;
 739         }
 740         return tomoyo_update_manager_entry(data, head->w.is_delete);
 741 }
 742
 743 /**
 744  * tomoyo_read_manager - Read manager policy.
 745  *
 746  * @head: Pointer to "struct tomoyo_io_buffer".
 747  *
 748  * Caller holds tomoyo_read_lock().
 749  */
 750 static void tomoyo_read_manager(struct tomoyo_io_buffer *head)
 751 {
 752         if (head->r.eof)
 753                 return;
 754         list_for_each_cookie(head->r.acl, &tomoyo_kernel_namespace.
 755                              policy_list[TOMOYO_ID_MANAGER]) {
 756                 struct tomoyo_manager *ptr =
 757                         list_entry(head->r.acl, typeof(*ptr), head.list);
 758                 if (ptr->head.is_deleted)
 759                         continue;
 760                 if (!tomoyo_flush(head))
 761                         return;
 762                 tomoyo_set_string(head, ptr->manager->name);
 763                 tomoyo_set_lf(head);
 764         }
 765         head->r.eof = true;
 766 }
 767
 768 /**
 769  * tomoyo_manager - Check whether the current process is a policy manager.
 770  *
 771  * Returns true if the current process is permitted to modify policy
 772  * via /sys/kernel/security/tomoyo/ interface.
 773  *
 774  * Caller holds tomoyo_read_lock().
 775  */
 776 static bool tomoyo_manager(void)
 777 {
 778         struct tomoyo_manager *ptr;
 779         const char *exe;
 780         const struct task_struct *task = current;
 781         const struct tomoyo_path_info *domainname = tomoyo_domain()->domainname;
 782         bool found = false;
 783
 784         if (!tomoyo_policy_loaded)
 785                 return true;
 786         if (!tomoyo_manage_by_non_root && (task->cred->uid || task->cred->euid))
 787                 return false;
 788         list_for_each_entry_rcu(ptr, &tomoyo_kernel_namespace.
 789                                 policy_list[TOMOYO_ID_MANAGER], head.list) {
 790                 if (!ptr->head.is_deleted && ptr->is_domain
 791                     && !tomoyo_pathcmp(domainname, ptr->manager)) {
 792                         found = true;
 793                         break;
 794                 }
 795         }
 796         if (found)
 797                 return true;
 798         exe = tomoyo_get_exe();
 799         if (!exe)
 800                 return false;
 801         list_for_each_entry_rcu(ptr, &tomoyo_kernel_namespace.
 802                                 policy_list[TOMOYO_ID_MANAGER], head.list) {
 803                 if (!ptr->head.is_deleted && !ptr->is_domain
 804                     && !strcmp(exe, ptr->manager->name)) {
 805                         found = true;
 806                         break;
 807                 }
 808         }
 809         if (!found) { /* Reduce error messages. */
 810                 static pid_t last_pid;
 811                 const pid_t pid = current->pid;
 812                 if (last_pid != pid) {
 813                         printk(KERN_WARNING "%s ( %s ) is not permitted to "
 814                                "update policies.\n", domainname->name, exe);
 815                         last_pid = pid;
 816                 }
 817         }
 818         kfree(exe);
 819         return found;
 820 }
 821
 822 /**
 823  * tomoyo_select_domain - Parse select command.
 824  *
 825  * @head: Pointer to "struct tomoyo_io_buffer".
 826  * @data: String to parse.
 827  *
 828  * Returns true on success, false otherwise.
 829  *
 830  * Caller holds tomoyo_read_lock().
 831  */
 832 static bool tomoyo_select_domain(struct tomoyo_io_buffer *head,
 833                                  const char *data)
 834 {
 835         unsigned int pid;
 836         struct tomoyo_domain_info *domain = NULL;
 837         bool global_pid = false;
 838         if (strncmp(data, "select ", 7))
 839                 return false;
 840         data += 7;
 841         if (sscanf(data, "pid=%u", &pid) == 1 ||
 842             (global_pid = true, sscanf(data, "global-pid=%u", &pid) == 1)) {
 843                 struct task_struct *p;
 844                 rcu_read_lock();
 845                 read_lock(&tasklist_lock);
 846                 if (global_pid)
 847                         p = find_task_by_pid_ns(pid, &init_pid_ns);
 848                 else
 849                         p = find_task_by_vpid(pid);
 850                 if (p)
 851                         domain = tomoyo_real_domain(p);
 852                 read_unlock(&tasklist_lock);
 853                 rcu_read_unlock();
 854         } else if (!strncmp(data, "domain=", 7)) {
 855                 if (tomoyo_domain_def(data + 7))
 856                         domain = tomoyo_find_domain(data + 7);
 857         } else
 858                 return false;
 859         head->w.domain = domain;
 860         /* Accessing read_buf is safe because head->io_sem is held. */
 861         if (!head->read_buf)
 862                 return true; /* Do nothing if open(O_WRONLY). */
 863         memset(&head->r, 0, sizeof(head->r));
 864         head->r.print_this_domain_only = true;
 865         if (domain)
 866                 head->r.domain = &domain->list;
 867         else
 868                 head->r.eof = 1;
 869         tomoyo_io_printf(head, "# select %s\n", data);
 870         if (domain && domain->is_deleted)
 871                 tomoyo_io_printf(head, "# This is a deleted domain.\n");
 872         return true;
 873 }
 874
 875 /**
 876  * tomoyo_delete_domain - Delete a domain.
 877  *
 878  * @domainname: The name of domain.
 879  *
 880  * Returns 0.
 881  *
 882  * Caller holds tomoyo_read_lock().
 883  */
 884 static int tomoyo_delete_domain(char *domainname)
 885 {
 886         struct tomoyo_domain_info *domain;
 887         struct tomoyo_path_info name;
 888
 889         name.name = domainname;
 890         tomoyo_fill_path_info(&name);
 891         if (mutex_lock_interruptible(&tomoyo_policy_lock))
 892                 return 0;
 893         /* Is there an active domain? */
 894         list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
 895                 /* Never delete tomoyo_kernel_domain */
 896                 if (domain == &tomoyo_kernel_domain)
 897                         continue;
 898                 if (domain->is_deleted ||
 899                     tomoyo_pathcmp(domain->domainname, &name))
 900                         continue;
 901                 domain->is_deleted = true;
 902                 break;
 903         }
 904         mutex_unlock(&tomoyo_policy_lock);
 905         return 0;
 906 }
 907
 908 /**
 909  * tomoyo_write_domain2 - Write domain policy.
 910  *
 911  * @ns:        Pointer to "struct tomoyo_policy_namespace".
 912  * @list:      Pointer to "struct list_head".
 913  * @data:      Policy to be interpreted.
 914  * @is_delete: True if it is a delete request.
 915  *
 916  * Returns 0 on success, negative value otherwise.
 917  *
 918  * Caller holds tomoyo_read_lock().
 919  */
 920 static int tomoyo_write_domain2(struct tomoyo_policy_namespace *ns,
 921                                 struct list_head *list, char *data,
 922                                 const bool is_delete)
 923 {
 924         struct tomoyo_acl_param param = {
 925                 .ns = ns,
 926                 .list = list,
 927                 .data = data,
 928                 .is_delete = is_delete,
 929         };
 930         static const struct {
 931                 const char *keyword;
 932                 int (*write) (struct tomoyo_acl_param *);
 933         } tomoyo_callback[1] = {
 934                 { "file ", tomoyo_write_file },
 935         };
 936         u8 i;
 937         for (i = 0; i < 1; i++) {
 938                 if (!tomoyo_str_starts(&param.data,
 939                                        tomoyo_callback[i].keyword))
 940                         continue;
 941                 return tomoyo_callback[i].write(&param);
 942         }
 943         return -EINVAL;
 944 }
 945
 946 /* String table for domain flags. */
 947 const char * const tomoyo_dif[TOMOYO_MAX_DOMAIN_INFO_FLAGS] = {
 948         [TOMOYO_DIF_QUOTA_WARNED]      = "quota_exceeded\n",
 949         [TOMOYO_DIF_TRANSITION_FAILED] = "transition_failed\n",
 950 };
 951
 952 /**
 953  * tomoyo_write_domain - Write domain policy.
 954  *
 955  * @head: Pointer to "struct tomoyo_io_buffer".
 956  *
 957  * Returns 0 on success, negative value otherwise.
 958  *
 959  * Caller holds tomoyo_read_lock().
 960  */
 961 static int tomoyo_write_domain(struct tomoyo_io_buffer *head)
 962 {
 963         char *data = head->write_buf;
 964         struct tomoyo_policy_namespace *ns;
 965         struct tomoyo_domain_info *domain = head->w.domain;
 966         const bool is_delete = head->w.is_delete;
 967         bool is_select = !is_delete && tomoyo_str_starts(&data, "select ");
 968         unsigned int profile;
 969         if (*data == '<') {
 970                 domain = NULL;
 971                 if (is_delete)
 972                         tomoyo_delete_domain(data);
 973                 else if (is_select)
 974                         domain = tomoyo_find_domain(data);
 975                 else
 976                         domain = tomoyo_assign_domain(data, false);
 977                 head->w.domain = domain;
 978                 return 0;
 979         }
 980         if (!domain)
 981                 return -EINVAL;
 982         ns = domain->ns;
 983         if (sscanf(data, "use_profile %u", &profile) == 1
 984             && profile < TOMOYO_MAX_PROFILES) {
 985                 if (!tomoyo_policy_loaded || ns->profile_ptr[profile])
 986                         domain->profile = (u8) profile;
 987                 return 0;
 988         }
 989         if (sscanf(data, "use_group %u\n", &profile) == 1
 990             && profile < TOMOYO_MAX_ACL_GROUPS) {
 991                 if (!is_delete)
 992                         domain->group = (u8) profile;
 993                 return 0;
 994         }
 995         for (profile = 0; profile < TOMOYO_MAX_DOMAIN_INFO_FLAGS; profile++) {
 996                 const char *cp = tomoyo_dif[profile];
 997                 if (strncmp(data, cp, strlen(cp) - 1))
 998                         continue;
 999                 domain->flags[profile] = !is_delete;
1000                 return 0;
1001         }
1002         return tomoyo_write_domain2(ns, &domain->acl_info_list, data,
1003                                     is_delete);
1004 }
1005
1006 /**
1007  * tomoyo_set_group - Print "acl_group " header keyword and category name.
1008  *
1009  * @head:     Pointer to "struct tomoyo_io_buffer".
1010  * @category: Category name.
1011  *
1012  * Returns nothing.
1013  */
1014 static void tomoyo_set_group(struct tomoyo_io_buffer *head,
1015                              const char *category)
1016 {
1017         if (head->type == TOMOYO_EXCEPTIONPOLICY) {
1018                 tomoyo_print_namespace(head);
1019                 tomoyo_io_printf(head, "acl_group %u ",
1020                                  head->r.acl_group_index);
1021         }
1022         tomoyo_set_string(head, category);
1023 }
1024
1025 /**
1026  * tomoyo_print_entry - Print an ACL entry.
1027  *
1028  * @head: Pointer to "struct tomoyo_io_buffer".
1029  * @acl:  Pointer to an ACL entry.
1030  *
1031  * Returns true on success, false otherwise.
1032  */
1033 static bool tomoyo_print_entry(struct tomoyo_io_buffer *head,
1034                                struct tomoyo_acl_info *acl)
1035 {
1036         const u8 acl_type = acl->type;
1037         bool first = true;
1038         u8 bit;
1039
1040         if (acl->is_deleted)
1041                 return true;
1042         if (!tomoyo_flush(head))
1043                 return false;
1044         else if (acl_type == TOMOYO_TYPE_PATH_ACL) {
1045                 struct tomoyo_path_acl *ptr =
1046                         container_of(acl, typeof(*ptr), head);
1047                 const u16 perm = ptr->perm;
1048                 for (bit = 0; bit < TOMOYO_MAX_PATH_OPERATION; bit++) {
1049                         if (!(perm & (1 << bit)))
1050                                 continue;
1051                         if (head->r.print_transition_related_only &&
1052                             bit != TOMOYO_TYPE_EXECUTE)
1053                                 continue;
1054                         if (first) {
1055                                 tomoyo_set_group(head, "file ");
1056                                 first = false;
1057                         } else {
1058                                 tomoyo_set_slash(head);
1059                         }
1060                         tomoyo_set_string(head, tomoyo_path_keyword[bit]);
1061                 }
1062                 if (first)
1063                         return true;
1064                 tomoyo_print_name_union(head, &ptr->name);
1065         } else if (head->r.print_transition_related_only) {
1066                 return true;
1067         } else if (acl_type == TOMOYO_TYPE_PATH2_ACL) {
1068                 struct tomoyo_path2_acl *ptr =
1069                         container_of(acl, typeof(*ptr), head);
1070                 const u8 perm = ptr->perm;
1071                 for (bit = 0; bit < TOMOYO_MAX_PATH2_OPERATION; bit++) {
1072                         if (!(perm & (1 << bit)))
1073                                 continue;
1074                         if (first) {
1075                                 tomoyo_set_group(head, "file ");
1076                                 first = false;
1077                         } else {
1078                                 tomoyo_set_slash(head);
1079                         }
1080                         tomoyo_set_string(head, tomoyo_mac_keywords
1081                                           [tomoyo_pp2mac[bit]]);
1082                 }
1083                 if (first)
1084                         return true;
1085                 tomoyo_print_name_union(head, &ptr->name1);
1086                 tomoyo_print_name_union(head, &ptr->name2);
1087         } else if (acl_type == TOMOYO_TYPE_PATH_NUMBER_ACL) {
1088                 struct tomoyo_path_number_acl *ptr =
1089                         container_of(acl, typeof(*ptr), head);
1090                 const u8 perm = ptr->perm;
1091                 for (bit = 0; bit < TOMOYO_MAX_PATH_NUMBER_OPERATION; bit++) {
1092                         if (!(perm & (1 << bit)))
1093                                 continue;
1094                         if (first) {
1095                                 tomoyo_set_group(head, "file ");
1096                                 first = false;
1097                         } else {
1098                                 tomoyo_set_slash(head);
1099                         }
1100                         tomoyo_set_string(head, tomoyo_mac_keywords
1101                                           [tomoyo_pn2mac[bit]]);
1102                 }
1103                 if (first)
1104                         return true;
1105                 tomoyo_print_name_union(head, &ptr->name);
1106                 tomoyo_print_number_union(head, &ptr->number);
1107         } else if (acl_type == TOMOYO_TYPE_MKDEV_ACL) {
1108                 struct tomoyo_mkdev_acl *ptr =
1109                         container_of(acl, typeof(*ptr), head);
1110                 const u8 perm = ptr->perm;
1111                 for (bit = 0; bit < TOMOYO_MAX_MKDEV_OPERATION; bit++) {
1112                         if (!(perm & (1 << bit)))
1113                                 continue;
1114                         if (first) {
1115                                 tomoyo_set_group(head, "file ");
1116                                 first = false;
1117                         } else {
1118                                 tomoyo_set_slash(head);
1119                         }
1120                         tomoyo_set_string(head, tomoyo_mac_keywords
1121                                           [tomoyo_pnnn2mac[bit]]);
1122                 }
1123                 if (first)
1124                         return true;
1125                 tomoyo_print_name_union(head, &ptr->name);
1126                 tomoyo_print_number_union(head, &ptr->mode);
1127                 tomoyo_print_number_union(head, &ptr->major);
1128                 tomoyo_print_number_union(head, &ptr->minor);
1129         } else if (acl_type == TOMOYO_TYPE_MOUNT_ACL) {
1130                 struct tomoyo_mount_acl *ptr =
1131                         container_of(acl, typeof(*ptr), head);
1132                 tomoyo_set_group(head, "file mount");
1133                 tomoyo_print_name_union(head, &ptr->dev_name);
1134                 tomoyo_print_name_union(head, &ptr->dir_name);
1135                 tomoyo_print_name_union(head, &ptr->fs_type);
1136                 tomoyo_print_number_union(head, &ptr->flags);
1137         }
1138         tomoyo_set_lf(head);
1139         return true;
1140 }
1141
1142 /**
1143  * tomoyo_read_domain2 - Read domain policy.
1144  *
1145  * @head: Pointer to "struct tomoyo_io_buffer".
1146  * @list: Pointer to "struct list_head".
1147  *
1148  * Caller holds tomoyo_read_lock().
1149  *
1150  * Returns true on success, false otherwise.
1151  */
1152 static bool tomoyo_read_domain2(struct tomoyo_io_buffer *head,
1153                                 struct list_head *list)
1154 {
1155         list_for_each_cookie(head->r.acl, list) {
1156                 struct tomoyo_acl_info *ptr =
1157                         list_entry(head->r.acl, typeof(*ptr), list);
1158                 if (!tomoyo_print_entry(head, ptr))
1159                         return false;
1160         }
1161         head->r.acl = NULL;
1162         return true;
1163 }
1164
1165 /**
1166  * tomoyo_read_domain - Read domain policy.
1167  *
1168  * @head: Pointer to "struct tomoyo_io_buffer".
1169  *
1170  * Caller holds tomoyo_read_lock().
1171  */
1172 static void tomoyo_read_domain(struct tomoyo_io_buffer *head)
1173 {
1174         if (head->r.eof)
1175                 return;
1176         list_for_each_cookie(head->r.domain, &tomoyo_domain_list) {
1177                 struct tomoyo_domain_info *domain =
1178                         list_entry(head->r.domain, typeof(*domain), list);
1179                 switch (head->r.step) {
1180                         u8 i;
1181                 case 0:
1182                         if (domain->is_deleted &&
1183                             !head->r.print_this_domain_only)
1184                                 continue;
1185                         /* Print domainname and flags. */
1186                         tomoyo_set_string(head, domain->domainname->name);
1187                         tomoyo_set_lf(head);
1188                         tomoyo_io_printf(head, "use_profile %u\n",
1189                                          domain->profile);
1190                         tomoyo_io_printf(head, "use_group %u\n",
1191                                          domain->group);
1192                         for (i = 0; i < TOMOYO_MAX_DOMAIN_INFO_FLAGS; i++)
1193                                 if (domain->flags[i])
1194                                         tomoyo_set_string(head, tomoyo_dif[i]);
1195                         head->r.step++;
1196                         tomoyo_set_lf(head);
1197                         /* fall through */
1198                 case 1:
1199                         if (!tomoyo_read_domain2(head, &domain->acl_info_list))
1200                                 return;
1201                         head->r.step++;
1202                         if (!tomoyo_set_lf(head))
1203                                 return;
1204                         /* fall through */
1205                 case 2:
1206                         head->r.step = 0;
1207                         if (head->r.print_this_domain_only)
1208                                 goto done;
1209                 }
1210         }
1211  done:
1212         head->r.eof = true;
1213 }
1214
1215 /**
1216  * tomoyo_write_pid: Specify PID to obtain domainname.
1217  *
1218  * @head: Pointer to "struct tomoyo_io_buffer".
1219  *
1220  * Returns 0.
1221  */
1222 static int tomoyo_write_pid(struct tomoyo_io_buffer *head)
1223 {
1224         head->r.eof = false;
1225         return 0;
1226 }
1227
1228 /**
1229  * tomoyo_read_pid - Get domainname of the specified PID.
1230  *
1231  * @head: Pointer to "struct tomoyo_io_buffer".
1232  *
1233  * Returns the domainname which the specified PID is in on success,
1234  * empty string otherwise.
1235  * The PID is specified by tomoyo_write_pid() so that the user can obtain
1236  * using read()/write() interface rather than sysctl() interface.
1237  */
1238 static void tomoyo_read_pid(struct tomoyo_io_buffer *head)
1239 {
1240         char *buf = head->write_buf;
1241         bool global_pid = false;
1242         unsigned int pid;
1243         struct task_struct *p;
1244         struct tomoyo_domain_info *domain = NULL;
1245
1246         /* Accessing write_buf is safe because head->io_sem is held. */
1247         if (!buf) {
1248                 head->r.eof = true;
1249                 return; /* Do nothing if open(O_RDONLY). */
1250         }
1251         if (head->r.w_pos || head->r.eof)
1252                 return;
1253         head->r.eof = true;
1254         if (tomoyo_str_starts(&buf, "global-pid "))
1255                 global_pid = true;
1256         pid = (unsigned int) simple_strtoul(buf, NULL, 10);
1257         rcu_read_lock();
1258         read_lock(&tasklist_lock);
1259         if (global_pid)
1260                 p = find_task_by_pid_ns(pid, &init_pid_ns);
1261         else
1262                 p = find_task_by_vpid(pid);
1263         if (p)
1264                 domain = tomoyo_real_domain(p);
1265         read_unlock(&tasklist_lock);
1266         rcu_read_unlock();
1267         if (!domain)
1268                 return;
1269         tomoyo_io_printf(head, "%u %u ", pid, domain->profile);
1270         tomoyo_set_string(head, domain->domainname->name);
1271 }
1272
1273 static const char *tomoyo_transition_type[TOMOYO_MAX_TRANSITION_TYPE] = {
1274         [TOMOYO_TRANSITION_CONTROL_NO_RESET]      = "no_reset_domain ",
1275         [TOMOYO_TRANSITION_CONTROL_RESET]         = "reset_domain ",
1276         [TOMOYO_TRANSITION_CONTROL_NO_INITIALIZE] = "no_initialize_domain ",
1277         [TOMOYO_TRANSITION_CONTROL_INITIALIZE]    = "initialize_domain ",
1278         [TOMOYO_TRANSITION_CONTROL_NO_KEEP]       = "no_keep_domain ",
1279         [TOMOYO_TRANSITION_CONTROL_KEEP]          = "keep_domain ",
1280 };
1281
1282 static const char *tomoyo_group_name[TOMOYO_MAX_GROUP] = {
1283         [TOMOYO_PATH_GROUP]   = "path_group ",
1284         [TOMOYO_NUMBER_GROUP] = "number_group ",
1285 };
1286
1287 /**
1288  * tomoyo_write_exception - Write exception policy.
1289  *
1290  * @head: Pointer to "struct tomoyo_io_buffer".
1291  *
1292  * Returns 0 on success, negative value otherwise.
1293  *
1294  * Caller holds tomoyo_read_lock().
1295  */
1296 static int tomoyo_write_exception(struct tomoyo_io_buffer *head)
1297 {
1298         const bool is_delete = head->w.is_delete;
1299         struct tomoyo_acl_param param = {
1300                 .ns = head->w.ns,
1301                 .is_delete = is_delete,
1302                 .data = head->write_buf,
1303         };
1304         u8 i;
1305         if (tomoyo_str_starts(&param.data, "aggregator "))
1306                 return tomoyo_write_aggregator(&param);
1307         for (i = 0; i < TOMOYO_MAX_TRANSITION_TYPE; i++)
1308                 if (tomoyo_str_starts(&param.data, tomoyo_transition_type[i]))
1309                         return tomoyo_write_transition_control(&param, i);
1310         for (i = 0; i < TOMOYO_MAX_GROUP; i++)
1311                 if (tomoyo_str_starts(&param.data, tomoyo_group_name[i]))
1312                         return tomoyo_write_group(&param, i);
1313         if (tomoyo_str_starts(&param.data, "acl_group ")) {
1314                 unsigned int group;
1315                 char *data;
1316                 group = simple_strtoul(param.data, &data, 10);
1317                 if (group < TOMOYO_MAX_ACL_GROUPS && *data++ == ' ')
1318                         return tomoyo_write_domain2
1319                                 (head->w.ns, &head->w.ns->acl_group[group],
1320                                  data, is_delete);
1321         }
1322         return -EINVAL;
1323 }
1324
1325 /**
1326  * tomoyo_read_group - Read "struct tomoyo_path_group"/"struct tomoyo_number_group" list.
1327  *
1328  * @head: Pointer to "struct tomoyo_io_buffer".
1329  * @idx:  Index number.
1330  *
1331  * Returns true on success, false otherwise.
1332  *
1333  * Caller holds tomoyo_read_lock().
1334  */
1335 static bool tomoyo_read_group(struct tomoyo_io_buffer *head, const int idx)
1336 {
1337         struct tomoyo_policy_namespace *ns =
1338                 container_of(head->r.ns, typeof(*ns), namespace_list);
1339         struct list_head *list = &ns->group_list[idx];
1340         list_for_each_cookie(head->r.group, list) {
1341                 struct tomoyo_group *group =
1342                         list_entry(head->r.group, typeof(*group), head.list);
1343                 list_for_each_cookie(head->r.acl, &group->member_list) {
1344                         struct tomoyo_acl_head *ptr =
1345                                 list_entry(head->r.acl, typeof(*ptr), list);
1346                         if (ptr->is_deleted)
1347                                 continue;
1348                         if (!tomoyo_flush(head))
1349                                 return false;
1350                         tomoyo_print_namespace(head);
1351                         tomoyo_set_string(head, tomoyo_group_name[idx]);
1352                         tomoyo_set_string(head, group->group_name->name);
1353                         if (idx == TOMOYO_PATH_GROUP) {
1354                                 tomoyo_set_space(head);
1355                                 tomoyo_set_string(head, container_of
1356                                                (ptr, struct tomoyo_path_group,
1357                                                 head)->member_name->name);
1358                         } else if (idx == TOMOYO_NUMBER_GROUP) {
1359                                 tomoyo_print_number_union(head, &container_of
1360                                                           (ptr,
1361                                                    struct tomoyo_number_group,
1362                                                            head)->number);
1363                         }
1364                         tomoyo_set_lf(head);
1365                 }
1366                 head->r.acl = NULL;
1367         }
1368         head->r.group = NULL;
1369         return true;
1370 }
1371
1372 /**
1373  * tomoyo_read_policy - Read "struct tomoyo_..._entry" list.
1374  *
1375  * @head: Pointer to "struct tomoyo_io_buffer".
1376  * @idx:  Index number.
1377  *
1378  * Returns true on success, false otherwise.
1379  *
1380  * Caller holds tomoyo_read_lock().
1381  */
1382 static bool tomoyo_read_policy(struct tomoyo_io_buffer *head, const int idx)
1383 {
1384         struct tomoyo_policy_namespace *ns =
1385                 container_of(head->r.ns, typeof(*ns), namespace_list);
1386         struct list_head *list = &ns->policy_list[idx];
1387         list_for_each_cookie(head->r.acl, list) {
1388                 struct tomoyo_acl_head *acl =
1389                         container_of(head->r.acl, typeof(*acl), list);
1390                 if (acl->is_deleted)
1391                         continue;
1392                 if (!tomoyo_flush(head))
1393                         return false;
1394                 switch (idx) {
1395                 case TOMOYO_ID_TRANSITION_CONTROL:
1396                         {
1397                                 struct tomoyo_transition_control *ptr =
1398                                         container_of(acl, typeof(*ptr), head);
1399                                 tomoyo_print_namespace(head);
1400                                 tomoyo_set_string(head, tomoyo_transition_type
1401                                                   [ptr->type]);
1402                                 tomoyo_set_string(head, ptr->program ?
1403                                                   ptr->program->name : "any");
1404                                 tomoyo_set_string(head, " from ");
1405                                 tomoyo_set_string(head, ptr->domainname ?
1406                                                   ptr->domainname->name :
1407                                                   "any");
1408                         }
1409                         break;
1410                 case TOMOYO_ID_AGGREGATOR:
1411                         {
1412                                 struct tomoyo_aggregator *ptr =
1413                                         container_of(acl, typeof(*ptr), head);
1414                                 tomoyo_print_namespace(head);
1415                                 tomoyo_set_string(head, "aggregator ");
1416                                 tomoyo_set_string(head,
1417                                                   ptr->original_name->name);
1418                                 tomoyo_set_space(head);
1419                                 tomoyo_set_string(head,
1420                                                ptr->aggregated_name->name);
1421                         }
1422                         break;
1423                 default:
1424                         continue;
1425                 }
1426                 tomoyo_set_lf(head);
1427         }
1428         head->r.acl = NULL;
1429         return true;
1430 }
1431
1432 /**
1433  * tomoyo_read_exception - Read exception policy.
1434  *
1435  * @head: Pointer to "struct tomoyo_io_buffer".
1436  *
1437  * Caller holds tomoyo_read_lock().
1438  */
1439 static void tomoyo_read_exception(struct tomoyo_io_buffer *head)
1440 {
1441         struct tomoyo_policy_namespace *ns =
1442                 container_of(head->r.ns, typeof(*ns), namespace_list);
1443         if (head->r.eof)
1444                 return;
1445         while (head->r.step < TOMOYO_MAX_POLICY &&
1446                tomoyo_read_policy(head, head->r.step))
1447                 head->r.step++;
1448         if (head->r.step < TOMOYO_MAX_POLICY)
1449                 return;
1450         while (head->r.step < TOMOYO_MAX_POLICY + TOMOYO_MAX_GROUP &&
1451                tomoyo_read_group(head, head->r.step - TOMOYO_MAX_POLICY))
1452                 head->r.step++;
1453         if (head->r.step < TOMOYO_MAX_POLICY + TOMOYO_MAX_GROUP)
1454                 return;
1455         while (head->r.step < TOMOYO_MAX_POLICY + TOMOYO_MAX_GROUP
1456                + TOMOYO_MAX_ACL_GROUPS) {
1457                 head->r.acl_group_index = head->r.step - TOMOYO_MAX_POLICY
1458                         - TOMOYO_MAX_GROUP;
1459                 if (!tomoyo_read_domain2(head, &ns->acl_group
1460                                          [head->r.acl_group_index]))
1461                         return;
1462                 head->r.step++;
1463         }
1464         head->r.eof = true;
1465 }
1466
1467 /* Wait queue for kernel -> userspace notification. */
1468 static DECLARE_WAIT_QUEUE_HEAD(tomoyo_query_wait);
1469 /* Wait queue for userspace -> kernel notification. */
1470 static DECLARE_WAIT_QUEUE_HEAD(tomoyo_answer_wait);
1471
1472 /* Structure for query. */
1473 struct tomoyo_query {
1474         struct list_head list;
1475         char *query;
1476         size_t query_len;
1477         unsigned int serial;
1478         u8 timer;
1479         u8 answer;
1480         u8 retry;
1481 };
1482
1483 /* The list for "struct tomoyo_query". */
1484 static LIST_HEAD(tomoyo_query_list);
1485
1486 /* Lock for manipulating tomoyo_query_list. */
1487 static DEFINE_SPINLOCK(tomoyo_query_list_lock);
1488
1489 /*
1490  * Number of "struct file" referring /sys/kernel/security/tomoyo/query
1491  * interface.
1492  */
1493 static atomic_t tomoyo_query_observers = ATOMIC_INIT(0);
1494
1495 /**
1496  * tomoyo_add_entry - Add an ACL to current thread's domain. Used by learning mode.
1497  *
1498  * @domain: Pointer to "struct tomoyo_domain_info".
1499  * @header: Lines containing ACL.
1500  *
1501  * Returns nothing.
1502  */
1503 static void tomoyo_add_entry(struct tomoyo_domain_info *domain, char *header)
1504 {
1505         char *buffer;
1506         char *cp = strchr(header, '\n');
1507         int len;
1508         if (!cp)
1509                 return;
1510         cp = strchr(cp + 1, '\n');
1511         if (!cp)
1512                 return;
1513         *cp++ = '\0';
1514         len = strlen(cp) + 1;
1515         buffer = kmalloc(len, GFP_NOFS);
1516         if (!buffer)
1517                 return;
1518         snprintf(buffer, len - 1, "%s", cp);
1519         tomoyo_normalize_line(buffer);
1520         if (!tomoyo_write_domain2(domain->ns, &domain->acl_info_list, buffer,
1521                                   false))
1522                 tomoyo_update_stat(TOMOYO_STAT_POLICY_UPDATES);
1523         kfree(buffer);
1524 }
1525
1526 /**
1527  * tomoyo_supervisor - Ask for the supervisor's decision.
1528  *
1529  * @r:   Pointer to "struct tomoyo_request_info".
1530  * @fmt: The printf()'s format string, followed by parameters.
1531  *
1532  * Returns 0 if the supervisor decided to permit the access request which
1533  * violated the policy in enforcing mode, TOMOYO_RETRY_REQUEST if the
1534  * supervisor decided to retry the access request which violated the policy in
1535  * enforcing mode, 0 if it is not in enforcing mode, -EPERM otherwise.
1536  */
1537 int tomoyo_supervisor(struct tomoyo_request_info *r, const char *fmt, ...)
1538 {
1539         va_list args;
1540         int error;
1541         int len;
1542         static unsigned int tomoyo_serial;
1543         struct tomoyo_query entry = { };
1544         bool quota_exceeded = false;
1545         va_start(args, fmt);
1546         len = vsnprintf((char *) &len, 1, fmt, args) + 1;
1547         va_end(args);
1548         /* Write /sys/kernel/security/tomoyo/audit. */
1549         va_start(args, fmt);
1550         tomoyo_write_log2(r, len, fmt, args);
1551         va_end(args);
1552         /* Nothing more to do if granted. */
1553         if (r->granted)
1554                 return 0;
1555         if (r->mode)
1556                 tomoyo_update_stat(r->mode);
1557         switch (r->mode) {
1558         case TOMOYO_CONFIG_ENFORCING:
1559                 error = -EPERM;
1560                 if (atomic_read(&tomoyo_query_observers))
1561                         break;
1562                 goto out;
1563         case TOMOYO_CONFIG_LEARNING:
1564                 error = 0;
1565                 /* Check max_learning_entry parameter. */
1566                 if (tomoyo_domain_quota_is_ok(r))
1567                         break;
1568                 /* fall through */
1569         default:
1570                 return 0;
1571         }
1572         /* Get message. */
1573         va_start(args, fmt);
1574         entry.query = tomoyo_init_log(r, len, fmt, args);
1575         va_end(args);
1576         if (!entry.query)
1577                 goto out;
1578         entry.query_len = strlen(entry.query) + 1;
1579         if (!error) {
1580                 tomoyo_add_entry(r->domain, entry.query);
1581                 goto out;
1582         }
1583         len = tomoyo_round2(entry.query_len);
1584         spin_lock(&tomoyo_query_list_lock);
1585         if (tomoyo_memory_quota[TOMOYO_MEMORY_QUERY] &&
1586             tomoyo_memory_used[TOMOYO_MEMORY_QUERY] + len
1587             >= tomoyo_memory_quota[TOMOYO_MEMORY_QUERY]) {
1588                 quota_exceeded = true;
1589         } else {
1590                 entry.serial = tomoyo_serial++;
1591                 entry.retry = r->retry;
1592                 tomoyo_memory_used[TOMOYO_MEMORY_QUERY] += len;
1593                 list_add_tail(&entry.list, &tomoyo_query_list);
1594         }
1595         spin_unlock(&tomoyo_query_list_lock);
1596         if (quota_exceeded)
1597                 goto out;
1598         /* Give 10 seconds for supervisor's opinion. */
1599         while (entry.timer < 10) {
1600                 wake_up_all(&tomoyo_query_wait);
1601                 if (wait_event_interruptible_timeout
1602                     (tomoyo_answer_wait, entry.answer ||
1603                      !atomic_read(&tomoyo_query_observers), HZ))
1604                         break;
1605                 else
1606                         entry.timer++;
1607         }
1608         spin_lock(&tomoyo_query_list_lock);
1609         list_del(&entry.list);
1610         tomoyo_memory_used[TOMOYO_MEMORY_QUERY] -= len;
1611         spin_unlock(&tomoyo_query_list_lock);
1612         switch (entry.answer) {
1613         case 3: /* Asked to retry by administrator. */
1614                 error = TOMOYO_RETRY_REQUEST;
1615                 r->retry++;
1616                 break;
1617         case 1:
1618                 /* Granted by administrator. */
1619                 error = 0;
1620                 break;
1621         default:
1622                 /* Timed out or rejected by administrator. */
1623                 break;
1624         }
1625 out:
1626         kfree(entry.query);
1627         return error;
1628 }
1629
1630 /**
1631  * tomoyo_poll_query - poll() for /sys/kernel/security/tomoyo/query.
1632  *
1633  * @file: Pointer to "struct file".
1634  * @wait: Pointer to "poll_table".
1635  *
1636  * Returns POLLIN | POLLRDNORM when ready to read, 0 otherwise.
1637  *
1638  * Waits for access requests which violated policy in enforcing mode.
1639  */
1640 static int tomoyo_poll_query(struct file *file, poll_table *wait)
1641 {
1642         struct list_head *tmp;
1643         bool found = false;
1644         u8 i;
1645         for (i = 0; i < 2; i++) {
1646                 spin_lock(&tomoyo_query_list_lock);
1647                 list_for_each(tmp, &tomoyo_query_list) {
1648                         struct tomoyo_query *ptr =
1649                                 list_entry(tmp, typeof(*ptr), list);
1650                         if (ptr->answer)
1651                                 continue;
1652                         found = true;
1653                         break;
1654                 }
1655                 spin_unlock(&tomoyo_query_list_lock);
1656                 if (found)
1657                         return POLLIN | POLLRDNORM;
1658                 if (i)
1659                         break;
1660                 poll_wait(file, &tomoyo_query_wait, wait);
1661         }
1662         return 0;
1663 }
1664
1665 /**
1666  * tomoyo_read_query - Read access requests which violated policy in enforcing mode.
1667  *
1668  * @head: Pointer to "struct tomoyo_io_buffer".
1669  */
1670 static void tomoyo_read_query(struct tomoyo_io_buffer *head)
1671 {
1672         struct list_head *tmp;
1673         unsigned int pos = 0;
1674         size_t len = 0;
1675         char *buf;
1676         if (head->r.w_pos)
1677                 return;
1678         if (head->read_buf) {
1679                 kfree(head->read_buf);
1680                 head->read_buf = NULL;
1681         }
1682         spin_lock(&tomoyo_query_list_lock);
1683         list_for_each(tmp, &tomoyo_query_list) {
1684                 struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
1685                 if (ptr->answer)
1686                         continue;
1687                 if (pos++ != head->r.query_index)
1688                         continue;
1689                 len = ptr->query_len;
1690                 break;
1691         }
1692         spin_unlock(&tomoyo_query_list_lock);
1693         if (!len) {
1694                 head->r.query_index = 0;
1695                 return;
1696         }
1697         buf = kzalloc(len + 32, GFP_NOFS);
1698         if (!buf)
1699                 return;
1700         pos = 0;
1701         spin_lock(&tomoyo_query_list_lock);
1702         list_for_each(tmp, &tomoyo_query_list) {
1703                 struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
1704                 if (ptr->answer)
1705                         continue;
1706                 if (pos++ != head->r.query_index)
1707                         continue;
1708                 /*
1709                  * Some query can be skipped because tomoyo_query_list
1710                  * can change, but I don't care.
1711                  */
1712                 if (len == ptr->query_len)
1713                         snprintf(buf, len + 31, "Q%u-%hu\n%s", ptr->serial,
1714                                  ptr->retry, ptr->query);
1715                 break;
1716         }
1717         spin_unlock(&tomoyo_query_list_lock);
1718         if (buf[0]) {
1719                 head->read_buf = buf;
1720                 head->r.w[head->r.w_pos++] = buf;
1721                 head->r.query_index++;
1722         } else {
1723                 kfree(buf);
1724         }
1725 }
1726
1727 /**
1728  * tomoyo_write_answer - Write the supervisor's decision.
1729  *
1730  * @head: Pointer to "struct tomoyo_io_buffer".
1731  *
1732  * Returns 0 on success, -EINVAL otherwise.
1733  */
1734 static int tomoyo_write_answer(struct tomoyo_io_buffer *head)
1735 {
1736         char *data = head->write_buf;
1737         struct list_head *tmp;
1738         unsigned int serial;
1739         unsigned int answer;
1740         spin_lock(&tomoyo_query_list_lock);
1741         list_for_each(tmp, &tomoyo_query_list) {
1742                 struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
1743                 ptr->timer = 0;
1744         }
1745         spin_unlock(&tomoyo_query_list_lock);
1746         if (sscanf(data, "A%u=%u", &serial, &answer) != 2)
1747                 return -EINVAL;
1748         spin_lock(&tomoyo_query_list_lock);
1749         list_for_each(tmp, &tomoyo_query_list) {
1750                 struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
1751                 if (ptr->serial != serial)
1752                         continue;
1753                 if (!ptr->answer)
1754                         ptr->answer = answer;
1755                 break;
1756         }
1757         spin_unlock(&tomoyo_query_list_lock);
1758         return 0;
1759 }
1760
1761 /**
1762  * tomoyo_read_version: Get version.
1763  *
1764  * @head: Pointer to "struct tomoyo_io_buffer".
1765  *
1766  * Returns version information.
1767  */
1768 static void tomoyo_read_version(struct tomoyo_io_buffer *head)
1769 {
1770         if (!head->r.eof) {
1771                 tomoyo_io_printf(head, "2.4.0");
1772                 head->r.eof = true;
1773         }
1774 }
1775
1776 /**
1777  * tomoyo_read_self_domain - Get the current process's domainname.
1778  *
1779  * @head: Pointer to "struct tomoyo_io_buffer".
1780  *
1781  * Returns the current process's domainname.
1782  */
1783 static void tomoyo_read_self_domain(struct tomoyo_io_buffer *head)
1784 {
1785         if (!head->r.eof) {
1786                 /*
1787                  * tomoyo_domain()->domainname != NULL
1788                  * because every process belongs to a domain and
1789                  * the domain's name cannot be NULL.
1790                  */
1791                 tomoyo_io_printf(head, "%s", tomoyo_domain()->domainname->name);
1792                 head->r.eof = true;
1793         }
1794 }
1795
1796 /* String table for /sys/kernel/security/tomoyo/stat interface. */
1797 static const char * const tomoyo_policy_headers[TOMOYO_MAX_POLICY_STAT] = {
1798         [TOMOYO_STAT_POLICY_UPDATES]    = "update:",
1799         [TOMOYO_STAT_POLICY_LEARNING]   = "violation in learning mode:",
1800         [TOMOYO_STAT_POLICY_PERMISSIVE] = "violation in permissive mode:",
1801         [TOMOYO_STAT_POLICY_ENFORCING]  = "violation in enforcing mode:",
1802 };
1803
1804 /* String table for /sys/kernel/security/tomoyo/stat interface. */
1805 static const char * const tomoyo_memory_headers[TOMOYO_MAX_MEMORY_STAT] = {
1806         [TOMOYO_MEMORY_POLICY] = "policy:",
1807         [TOMOYO_MEMORY_AUDIT]  = "audit log:",
1808         [TOMOYO_MEMORY_QUERY]  = "query message:",
1809 };
1810
1811 /* Timestamp counter for last updated. */
1812 static unsigned int tomoyo_stat_updated[TOMOYO_MAX_POLICY_STAT];
1813 /* Counter for number of updates. */
1814 static unsigned int tomoyo_stat_modified[TOMOYO_MAX_POLICY_STAT];
1815
1816 /**
1817  * tomoyo_update_stat - Update statistic counters.
1818  *
1819  * @index: Index for policy type.
1820  *
1821  * Returns nothing.
1822  */
1823 void tomoyo_update_stat(const u8 index)
1824 {
1825         struct timeval tv;
1826         do_gettimeofday(&tv);
1827         /*
1828          * I don't use atomic operations because race condition is not fatal.
1829          */
1830         tomoyo_stat_updated[index]++;
1831         tomoyo_stat_modified[index] = tv.tv_sec;
1832 }
1833
1834 /**
1835  * tomoyo_read_stat - Read statistic data.
1836  *
1837  * @head: Pointer to "struct tomoyo_io_buffer".
1838  *
1839  * Returns nothing.
1840  */
1841 static void tomoyo_read_stat(struct tomoyo_io_buffer *head)
1842 {
1843         u8 i;
1844         unsigned int total = 0;
1845         if (head->r.eof)
1846                 return;
1847         for (i = 0; i < TOMOYO_MAX_POLICY_STAT; i++) {
1848                 tomoyo_io_printf(head, "Policy %-30s %10u",
1849                                  tomoyo_policy_headers[i],
1850                                  tomoyo_stat_updated[i]);
1851                 if (tomoyo_stat_modified[i]) {
1852                         struct tomoyo_time stamp;
1853                         tomoyo_convert_time(tomoyo_stat_modified[i], &stamp);
1854                         tomoyo_io_printf(head, " (Last: %04u/%02u/%02u "
1855                                          "%02u:%02u:%02u)",
1856                                          stamp.year, stamp.month, stamp.day,
1857                                          stamp.hour, stamp.min, stamp.sec);
1858                 }
1859                 tomoyo_set_lf(head);
1860         }
1861         for (i = 0; i < TOMOYO_MAX_MEMORY_STAT; i++) {
1862                 unsigned int used = tomoyo_memory_used[i];
1863                 total += used;
1864                 tomoyo_io_printf(head, "Memory used by %-22s %10u",
1865                                  tomoyo_memory_headers[i], used);
1866                 used = tomoyo_memory_quota[i];
1867                 if (used)
1868                         tomoyo_io_printf(head, " (Quota: %10u)", used);
1869                 tomoyo_set_lf(head);
1870         }
1871         tomoyo_io_printf(head, "Total memory used:                    %10u\n",
1872                          total);
1873         head->r.eof = true;
1874 }
1875
1876 /**
1877  * tomoyo_write_stat - Set memory quota.
1878  *
1879  * @head: Pointer to "struct tomoyo_io_buffer".
1880  *
1881  * Returns 0.
1882  */
1883 static int tomoyo_write_stat(struct tomoyo_io_buffer *head)
1884 {
1885         char *data = head->write_buf;
1886         u8 i;
1887         if (tomoyo_str_starts(&data, "Memory used by "))
1888                 for (i = 0; i < TOMOYO_MAX_MEMORY_STAT; i++)
1889                         if (tomoyo_str_starts(&data, tomoyo_memory_headers[i]))
1890                                 sscanf(data, "%u", &tomoyo_memory_quota[i]);
1891         return 0;
1892 }
1893
1894 /**
1895  * tomoyo_open_control - open() for /sys/kernel/security/tomoyo/ interface.
1896  *
1897  * @type: Type of interface.
1898  * @file: Pointer to "struct file".
1899  *
1900  * Returns 0 on success, negative value otherwise.
1901  */
1902 int tomoyo_open_control(const u8 type, struct file *file)
1903 {
1904         struct tomoyo_io_buffer *head = kzalloc(sizeof(*head), GFP_NOFS);
1905
1906         if (!head)
1907                 return -ENOMEM;
1908         mutex_init(&head->io_sem);
1909         head->type = type;
1910         switch (type) {
1911         case TOMOYO_DOMAINPOLICY:
1912                 /* /sys/kernel/security/tomoyo/domain_policy */
1913                 head->write = tomoyo_write_domain;
1914                 head->read = tomoyo_read_domain;
1915                 break;
1916         case TOMOYO_EXCEPTIONPOLICY:
1917                 /* /sys/kernel/security/tomoyo/exception_policy */
1918                 head->write = tomoyo_write_exception;
1919                 head->read = tomoyo_read_exception;
1920                 break;
1921         case TOMOYO_AUDIT:
1922                 /* /sys/kernel/security/tomoyo/audit */
1923                 head->poll = tomoyo_poll_log;
1924                 head->read = tomoyo_read_log;
1925                 break;
1926         case TOMOYO_SELFDOMAIN:
1927                 /* /sys/kernel/security/tomoyo/self_domain */
1928                 head->read = tomoyo_read_self_domain;
1929                 break;
1930         case TOMOYO_PROCESS_STATUS:
1931                 /* /sys/kernel/security/tomoyo/.process_status */
1932                 head->write = tomoyo_write_pid;
1933                 head->read = tomoyo_read_pid;
1934                 break;
1935         case TOMOYO_VERSION:
1936                 /* /sys/kernel/security/tomoyo/version */
1937                 head->read = tomoyo_read_version;
1938                 head->readbuf_size = 128;
1939                 break;
1940         case TOMOYO_STAT:
1941                 /* /sys/kernel/security/tomoyo/stat */
1942                 head->write = tomoyo_write_stat;
1943                 head->read = tomoyo_read_stat;
1944                 head->readbuf_size = 1024;
1945                 break;
1946         case TOMOYO_PROFILE:
1947                 /* /sys/kernel/security/tomoyo/profile */
1948                 head->write = tomoyo_write_profile;
1949                 head->read = tomoyo_read_profile;
1950                 break;
1951         case TOMOYO_QUERY: /* /sys/kernel/security/tomoyo/query */
1952                 head->poll = tomoyo_poll_query;
1953                 head->write = tomoyo_write_answer;
1954                 head->read = tomoyo_read_query;
1955                 break;
1956         case TOMOYO_MANAGER:
1957                 /* /sys/kernel/security/tomoyo/manager */
1958                 head->write = tomoyo_write_manager;
1959                 head->read = tomoyo_read_manager;
1960                 break;
1961         }
1962         if (!(file->f_mode & FMODE_READ)) {
1963                 /*
1964                  * No need to allocate read_buf since it is not opened
1965                  * for reading.
1966                  */
1967                 head->read = NULL;
1968                 head->poll = NULL;
1969         } else if (!head->poll) {
1970                 /* Don't allocate read_buf for poll() access. */
1971                 if (!head->readbuf_size)
1972                         head->readbuf_size = 4096 * 2;
1973                 head->read_buf = kzalloc(head->readbuf_size, GFP_NOFS);
1974                 if (!head->read_buf) {
1975                         kfree(head);
1976                         return -ENOMEM;
1977                 }
1978         }
1979         if (!(file->f_mode & FMODE_WRITE)) {
1980                 /*
1981                  * No need to allocate write_buf since it is not opened
1982                  * for writing.
1983                  */
1984                 head->write = NULL;
1985         } else if (head->write) {
1986                 head->writebuf_size = 4096 * 2;
1987                 head->write_buf = kzalloc(head->writebuf_size, GFP_NOFS);
1988                 if (!head->write_buf) {
1989                         kfree(head->read_buf);
1990                         kfree(head);
1991                         return -ENOMEM;
1992                 }
1993         }
1994         /*
1995          * If the file is /sys/kernel/security/tomoyo/query , increment the
1996          * observer counter.
1997          * The obserber counter is used by tomoyo_supervisor() to see if
1998          * there is some process monitoring /sys/kernel/security/tomoyo/query.
1999          */
2000         if (type == TOMOYO_QUERY)
2001                 atomic_inc(&tomoyo_query_observers);
2002         file->private_data = head;
2003         tomoyo_notify_gc(head, true);
2004         return 0;
2005 }
2006
2007 /**
2008  * tomoyo_poll_control - poll() for /sys/kernel/security/tomoyo/ interface.
2009  *
2010  * @file: Pointer to "struct file".
2011  * @wait: Pointer to "poll_table".
2012  *
2013  * Waits for read readiness.
2014  * /sys/kernel/security/tomoyo/query is handled by /usr/sbin/tomoyo-queryd and
2015  * /sys/kernel/security/tomoyo/audit is handled by /usr/sbin/tomoyo-auditd.
2016  */
2017 int tomoyo_poll_control(struct file *file, poll_table *wait)
2018 {
2019         struct tomoyo_io_buffer *head = file->private_data;
2020         if (!head->poll)
2021                 return -ENOSYS;
2022         return head->poll(file, wait);
2023 }
2024
2025 /**
2026  * tomoyo_set_namespace_cursor - Set namespace to read.
2027  *
2028  * @head: Pointer to "struct tomoyo_io_buffer".
2029  *
2030  * Returns nothing.
2031  */
2032 static inline void tomoyo_set_namespace_cursor(struct tomoyo_io_buffer *head)
2033 {
2034         struct list_head *ns;
2035         if (head->type != TOMOYO_EXCEPTIONPOLICY &&
2036             head->type != TOMOYO_PROFILE)
2037                 return;
2038         /*
2039          * If this is the first read, or reading previous namespace finished
2040          * and has more namespaces to read, update the namespace cursor.
2041          */
2042         ns = head->r.ns;
2043         if (!ns || (head->r.eof && ns->next != &tomoyo_namespace_list)) {
2044                 /* Clearing is OK because tomoyo_flush() returned true. */
2045                 memset(&head->r, 0, sizeof(head->r));
2046                 head->r.ns = ns ? ns->next : tomoyo_namespace_list.next;
2047         }
2048 }
2049
2050 /**
2051  * tomoyo_has_more_namespace - Check for unread namespaces.
2052  *
2053  * @head: Pointer to "struct tomoyo_io_buffer".
2054  *
2055  * Returns true if we have more entries to print, false otherwise.
2056  */
2057 static inline bool tomoyo_has_more_namespace(struct tomoyo_io_buffer *head)
2058 {
2059         return (head->type == TOMOYO_EXCEPTIONPOLICY ||
2060                 head->type == TOMOYO_PROFILE) && head->r.eof &&
2061                 head->r.ns->next != &tomoyo_namespace_list;
2062 }
2063
2064 /**
2065  * tomoyo_read_control - read() for /sys/kernel/security/tomoyo/ interface.
2066  *
2067  * @head:       Pointer to "struct tomoyo_io_buffer".
2068  * @buffer:     Poiner to buffer to write to.
2069  * @buffer_len: Size of @buffer.
2070  *
2071  * Returns bytes read on success, negative value otherwise.
2072  */
2073 ssize_t tomoyo_read_control(struct tomoyo_io_buffer *head, char __user *buffer,
2074                             const int buffer_len)
2075 {
2076         int len;
2077         int idx;
2078
2079         if (!head->read)
2080                 return -ENOSYS;
2081         if (mutex_lock_interruptible(&head->io_sem))
2082                 return -EINTR;
2083         head->read_user_buf = buffer;
2084         head->read_user_buf_avail = buffer_len;
2085         idx = tomoyo_read_lock();
2086         if (tomoyo_flush(head))
2087                 /* Call the policy handler. */
2088                 do {
2089                         tomoyo_set_namespace_cursor(head);
2090                         head->read(head);
2091                 } while (tomoyo_flush(head) &&
2092                          tomoyo_has_more_namespace(head));
2093         tomoyo_read_unlock(idx);
2094         len = head->read_user_buf - buffer;
2095         mutex_unlock(&head->io_sem);
2096         return len;
2097 }
2098
2099 /**
2100  * tomoyo_parse_policy - Parse a policy line.
2101  *
2102  * @head: Poiter to "struct tomoyo_io_buffer".
2103  * @line: Line to parse.
2104  *
2105  * Returns 0 on success, negative value otherwise.
2106  *
2107  * Caller holds tomoyo_read_lock().
2108  */
2109 static int tomoyo_parse_policy(struct tomoyo_io_buffer *head, char *line)
2110 {
2111         /* Delete request? */
2112         head->w.is_delete = !strncmp(line, "delete ", 7);
2113         if (head->w.is_delete)
2114                 memmove(line, line + 7, strlen(line + 7) + 1);
2115         /* Selecting namespace to update. */
2116         if (head->type == TOMOYO_EXCEPTIONPOLICY ||
2117             head->type == TOMOYO_PROFILE) {
2118                 if (*line == '<') {
2119                         char *cp = strchr(line, ' ');
2120                         if (cp) {
2121                                 *cp++ = '\0';
2122                                 head->w.ns = tomoyo_assign_namespace(line);
2123                                 memmove(line, cp, strlen(cp) + 1);
2124                         } else
2125                                 head->w.ns = NULL;
2126                 } else
2127                         head->w.ns = &tomoyo_kernel_namespace;
2128                 /* Don't allow updating if namespace is invalid. */
2129                 if (!head->w.ns)
2130                         return -ENOENT;
2131         }
2132         /* Do the update. */
2133         return head->write(head);
2134 }
2135
2136 /**
2137  * tomoyo_write_control - write() for /sys/kernel/security/tomoyo/ interface.
2138  *
2139  * @head:       Pointer to "struct tomoyo_io_buffer".
2140  * @buffer:     Pointer to buffer to read from.
2141  * @buffer_len: Size of @buffer.
2142  *
2143  * Returns @buffer_len on success, negative value otherwise.
2144  */
2145 ssize_t tomoyo_write_control(struct tomoyo_io_buffer *head,
2146                              const char __user *buffer, const int buffer_len)
2147 {
2148         int error = buffer_len;
2149         size_t avail_len = buffer_len;
2150         char *cp0 = head->write_buf;
2151         int idx;
2152         if (!head->write)
2153                 return -ENOSYS;
2154         if (!access_ok(VERIFY_READ, buffer, buffer_len))
2155                 return -EFAULT;
2156         if (mutex_lock_interruptible(&head->io_sem))
2157                 return -EINTR;
2158         idx = tomoyo_read_lock();
2159         /* Read a line and dispatch it to the policy handler. */
2160         while (avail_len > 0) {
2161                 char c;
2162                 if (head->w.avail >= head->writebuf_size - 1) {
2163                         const int len = head->writebuf_size * 2;
2164                         char *cp = kzalloc(len, GFP_NOFS);
2165                         if (!cp) {
2166                                 error = -ENOMEM;
2167                                 break;
2168                         }
2169                         memmove(cp, cp0, head->w.avail);
2170                         kfree(cp0);
2171                         head->write_buf = cp;
2172                         cp0 = cp;
2173                         head->writebuf_size = len;
2174                 }
2175                 if (get_user(c, buffer)) {
2176                         error = -EFAULT;
2177                         break;
2178                 }
2179                 buffer++;
2180                 avail_len--;
2181                 cp0[head->w.avail++] = c;
2182                 if (c != '\n')
2183                         continue;
2184                 cp0[head->w.avail - 1] = '\0';
2185                 head->w.avail = 0;
2186                 tomoyo_normalize_line(cp0);
2187                 if (!strcmp(cp0, "reset")) {
2188                         head->w.ns = &tomoyo_kernel_namespace;
2189                         head->w.domain = NULL;
2190                         memset(&head->r, 0, sizeof(head->r));
2191                         continue;
2192                 }
2193                 /* Don't allow updating policies by non manager programs. */
2194                 switch (head->type) {
2195                 case TOMOYO_PROCESS_STATUS:
2196                         /* This does not write anything. */
2197                         break;
2198                 case TOMOYO_DOMAINPOLICY:
2199                         if (tomoyo_select_domain(head, cp0))
2200                                 continue;
2201                         /* fall through */
2202                 case TOMOYO_EXCEPTIONPOLICY:
2203                         if (!strcmp(cp0, "select transition_only")) {
2204                                 head->r.print_transition_related_only = true;
2205                                 continue;
2206                         }
2207                         /* fall through */
2208                 default:
2209                         if (!tomoyo_manager()) {
2210                                 error = -EPERM;
2211                                 goto out;
2212                         }
2213                 }
2214                 switch (tomoyo_parse_policy(head, cp0)) {
2215                 case -EPERM:
2216                         error = -EPERM;
2217                         goto out;
2218                 case 0:
2219                         switch (head->type) {
2220                         case TOMOYO_DOMAINPOLICY:
2221                         case TOMOYO_EXCEPTIONPOLICY:
2222                         case TOMOYO_STAT:
2223                         case TOMOYO_PROFILE:
2224                         case TOMOYO_MANAGER:
2225                                 tomoyo_update_stat(TOMOYO_STAT_POLICY_UPDATES);
2226                                 break;
2227                         default:
2228                                 break;
2229                         }
2230                         break;
2231                 }
2232         }
2233 out:
2234         tomoyo_read_unlock(idx);
2235         mutex_unlock(&head->io_sem);
2236         return error;
2237 }
2238
2239 /**
2240  * tomoyo_close_control - close() for /sys/kernel/security/tomoyo/ interface.
2241  *
2242  * @head: Pointer to "struct tomoyo_io_buffer".
2243  *
2244  * Returns 0.
2245  */
2246 int tomoyo_close_control(struct tomoyo_io_buffer *head)
2247 {
2248         /*
2249          * If the file is /sys/kernel/security/tomoyo/query , decrement the
2250          * observer counter.
2251          */
2252         if (head->type == TOMOYO_QUERY &&
2253             atomic_dec_and_test(&tomoyo_query_observers))
2254                 wake_up_all(&tomoyo_answer_wait);
2255         tomoyo_notify_gc(head, false);
2256         return 0;
2257 }
2258
2259 /**
2260  * tomoyo_check_profile - Check all profiles currently assigned to domains are defined.
2261  */
2262 void tomoyo_check_profile(void)
2263 {
2264         struct tomoyo_domain_info *domain;
2265         const int idx = tomoyo_read_lock();
2266         tomoyo_policy_loaded = true;
2267         printk(KERN_INFO "TOMOYO: 2.4.0\n");
2268         list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
2269                 const u8 profile = domain->profile;
2270                 const struct tomoyo_policy_namespace *ns = domain->ns;
2271                 if (ns->profile_version != 20100903)
2272                         printk(KERN_ERR
2273                                "Profile version %u is not supported.\n",
2274                                ns->profile_version);
2275                 else if (!ns->profile_ptr[profile])
2276                         printk(KERN_ERR
2277                                "Profile %u (used by '%s') is not defined.\n",
2278                                profile, domain->domainname->name);
2279                 else
2280                         continue;
2281                 printk(KERN_ERR
2282                        "Userland tools for TOMOYO 2.4 must be installed and "
2283                        "policy must be initialized.\n");
2284                 printk(KERN_ERR "Please see http://tomoyo.sourceforge.jp/2.4/ "
2285                        "for more information.\n");
2286                 panic("STOP!");
2287         }
2288         tomoyo_read_unlock(idx);
2289         printk(KERN_INFO "Mandatory Access Control activated.\n");
2290 }
2291
2292 /**
2293  * tomoyo_load_builtin_policy - Load built-in policy.
2294  *
2295  * Returns nothing.
2296  */
2297 void __init tomoyo_load_builtin_policy(void)
2298 {
2299         /*
2300          * This include file is manually created and contains built-in policy
2301          * named "tomoyo_builtin_profile", "tomoyo_builtin_exception_policy",
2302          * "tomoyo_builtin_domain_policy", "tomoyo_builtin_manager",
2303          * "tomoyo_builtin_stat" in the form of "static char [] __initdata".
2304          */
2305 #include "builtin-policy.h"
2306         u8 i;
2307         const int idx = tomoyo_read_lock();
2308         for (i = 0; i < 5; i++) {
2309                 struct tomoyo_io_buffer head = { };
2310                 char *start = "";
2311                 switch (i) {
2312                 case 0:
2313                         start = tomoyo_builtin_profile;
2314                         head.type = TOMOYO_PROFILE;
2315                         head.write = tomoyo_write_profile;
2316                         break;
2317                 case 1:
2318                         start = tomoyo_builtin_exception_policy;
2319                         head.type = TOMOYO_EXCEPTIONPOLICY;
2320                         head.write = tomoyo_write_exception;
2321                         break;
2322                 case 2:
2323                         start = tomoyo_builtin_domain_policy;
2324                         head.type = TOMOYO_DOMAINPOLICY;
2325                         head.write = tomoyo_write_domain;
2326                         break;
2327                 case 3:
2328                         start = tomoyo_builtin_manager;
2329                         head.type = TOMOYO_MANAGER;
2330                         head.write = tomoyo_write_manager;
2331                         break;
2332                 case 4:
2333                         start = tomoyo_builtin_stat;
2334                         head.type = TOMOYO_STAT;
2335                         head.write = tomoyo_write_stat;
2336                         break;
2337                 }
2338                 while (1) {
2339                         char *end = strchr(start, '\n');
2340                         if (!end)
2341                                 break;
2342                         *end = '\0';
2343                         tomoyo_normalize_line(start);
2344                         head.write_buf = start;
2345                         tomoyo_parse_policy(&head, start);
2346                         start = end + 1;
2347                 }
2348         }
2349         tomoyo_read_unlock(idx);
2350 #ifdef CONFIG_SECURITY_TOMOYO_OMIT_USERSPACE_LOADER
2351         tomoyo_check_profile();
2352 #endif
2353 }