Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / security / tomoyo / condition.c
diff --git a/kernel/security/tomoyo/condition.c b/kernel/security/tomoyo/condition.c
new file mode 100644 (file)
index 0000000..6c4528d
--- /dev/null
@@ -0,0 +1,1094 @@
+/*
+ * security/tomoyo/condition.c
+ *
+ * Copyright (C) 2005-2011  NTT DATA CORPORATION
+ */
+
+#include "common.h"
+#include <linux/slab.h>
+
+/* List of "struct tomoyo_condition". */
+LIST_HEAD(tomoyo_condition_list);
+
+/**
+ * tomoyo_argv - Check argv[] in "struct linux_binbrm".
+ *
+ * @index:   Index number of @arg_ptr.
+ * @arg_ptr: Contents of argv[@index].
+ * @argc:    Length of @argv.
+ * @argv:    Pointer to "struct tomoyo_argv".
+ * @checked: Set to true if @argv[@index] was found.
+ *
+ * Returns true on success, false otherwise.
+ */
+static bool tomoyo_argv(const unsigned int index, const char *arg_ptr,
+                       const int argc, const struct tomoyo_argv *argv,
+                       u8 *checked)
+{
+       int i;
+       struct tomoyo_path_info arg;
+       arg.name = arg_ptr;
+       for (i = 0; i < argc; argv++, checked++, i++) {
+               bool result;
+               if (index != argv->index)
+                       continue;
+               *checked = 1;
+               tomoyo_fill_path_info(&arg);
+               result = tomoyo_path_matches_pattern(&arg, argv->value);
+               if (argv->is_not)
+                       result = !result;
+               if (!result)
+                       return false;
+       }
+       return true;
+}
+
+/**
+ * tomoyo_envp - Check envp[] in "struct linux_binbrm".
+ *
+ * @env_name:  The name of environment variable.
+ * @env_value: The value of environment variable.
+ * @envc:      Length of @envp.
+ * @envp:      Pointer to "struct tomoyo_envp".
+ * @checked:   Set to true if @envp[@env_name] was found.
+ *
+ * Returns true on success, false otherwise.
+ */
+static bool tomoyo_envp(const char *env_name, const char *env_value,
+                       const int envc, const struct tomoyo_envp *envp,
+                       u8 *checked)
+{
+       int i;
+       struct tomoyo_path_info name;
+       struct tomoyo_path_info value;
+       name.name = env_name;
+       tomoyo_fill_path_info(&name);
+       value.name = env_value;
+       tomoyo_fill_path_info(&value);
+       for (i = 0; i < envc; envp++, checked++, i++) {
+               bool result;
+               if (!tomoyo_path_matches_pattern(&name, envp->name))
+                       continue;
+               *checked = 1;
+               if (envp->value) {
+                       result = tomoyo_path_matches_pattern(&value,
+                                                            envp->value);
+                       if (envp->is_not)
+                               result = !result;
+               } else {
+                       result = true;
+                       if (!envp->is_not)
+                               result = !result;
+               }
+               if (!result)
+                       return false;
+       }
+       return true;
+}
+
+/**
+ * tomoyo_scan_bprm - Scan "struct linux_binprm".
+ *
+ * @ee:   Pointer to "struct tomoyo_execve".
+ * @argc: Length of @argc.
+ * @argv: Pointer to "struct tomoyo_argv".
+ * @envc: Length of @envp.
+ * @envp: Poiner to "struct tomoyo_envp".
+ *
+ * Returns true on success, false otherwise.
+ */
+static bool tomoyo_scan_bprm(struct tomoyo_execve *ee,
+                            const u16 argc, const struct tomoyo_argv *argv,
+                            const u16 envc, const struct tomoyo_envp *envp)
+{
+       struct linux_binprm *bprm = ee->bprm;
+       struct tomoyo_page_dump *dump = &ee->dump;
+       char *arg_ptr = ee->tmp;
+       int arg_len = 0;
+       unsigned long pos = bprm->p;
+       int offset = pos % PAGE_SIZE;
+       int argv_count = bprm->argc;
+       int envp_count = bprm->envc;
+       bool result = true;
+       u8 local_checked[32];
+       u8 *checked;
+       if (argc + envc <= sizeof(local_checked)) {
+               checked = local_checked;
+               memset(local_checked, 0, sizeof(local_checked));
+       } else {
+               checked = kzalloc(argc + envc, GFP_NOFS);
+               if (!checked)
+                       return false;
+       }
+       while (argv_count || envp_count) {
+               if (!tomoyo_dump_page(bprm, pos, dump)) {
+                       result = false;
+                       goto out;
+               }
+               pos += PAGE_SIZE - offset;
+               while (offset < PAGE_SIZE) {
+                       /* Read. */
+                       const char *kaddr = dump->data;
+                       const unsigned char c = kaddr[offset++];
+                       if (c && arg_len < TOMOYO_EXEC_TMPSIZE - 10) {
+                               if (c == '\\') {
+                                       arg_ptr[arg_len++] = '\\';
+                                       arg_ptr[arg_len++] = '\\';
+                               } else if (c > ' ' && c < 127) {
+                                       arg_ptr[arg_len++] = c;
+                               } else {
+                                       arg_ptr[arg_len++] = '\\';
+                                       arg_ptr[arg_len++] = (c >> 6) + '0';
+                                       arg_ptr[arg_len++] =
+                                               ((c >> 3) & 7) + '0';
+                                       arg_ptr[arg_len++] = (c & 7) + '0';
+                               }
+                       } else {
+                               arg_ptr[arg_len] = '\0';
+                       }
+                       if (c)
+                               continue;
+                       /* Check. */
+                       if (argv_count) {
+                               if (!tomoyo_argv(bprm->argc - argv_count,
+                                                arg_ptr, argc, argv,
+                                                checked)) {
+                                       result = false;
+                                       break;
+                               }
+                               argv_count--;
+                       } else if (envp_count) {
+                               char *cp = strchr(arg_ptr, '=');
+                               if (cp) {
+                                       *cp = '\0';
+                                       if (!tomoyo_envp(arg_ptr, cp + 1,
+                                                        envc, envp,
+                                                        checked + argc)) {
+                                               result = false;
+                                               break;
+                                       }
+                               }
+                               envp_count--;
+                       } else {
+                               break;
+                       }
+                       arg_len = 0;
+               }
+               offset = 0;
+               if (!result)
+                       break;
+       }
+out:
+       if (result) {
+               int i;
+               /* Check not-yet-checked entries. */
+               for (i = 0; i < argc; i++) {
+                       if (checked[i])
+                               continue;
+                       /*
+                        * Return true only if all unchecked indexes in
+                        * bprm->argv[] are not matched.
+                        */
+                       if (argv[i].is_not)
+                               continue;
+                       result = false;
+                       break;
+               }
+               for (i = 0; i < envc; envp++, i++) {
+                       if (checked[argc + i])
+                               continue;
+                       /*
+                        * Return true only if all unchecked environ variables
+                        * in bprm->envp[] are either undefined or not matched.
+                        */
+                       if ((!envp->value && !envp->is_not) ||
+                           (envp->value && envp->is_not))
+                               continue;
+                       result = false;
+                       break;
+               }
+       }
+       if (checked != local_checked)
+               kfree(checked);
+       return result;
+}
+
+/**
+ * tomoyo_scan_exec_realpath - Check "exec.realpath" parameter of "struct tomoyo_condition".
+ *
+ * @file:  Pointer to "struct file".
+ * @ptr:   Pointer to "struct tomoyo_name_union".
+ * @match: True if "exec.realpath=", false if "exec.realpath!=".
+ *
+ * Returns true on success, false otherwise.
+ */
+static bool tomoyo_scan_exec_realpath(struct file *file,
+                                     const struct tomoyo_name_union *ptr,
+                                     const bool match)
+{
+       bool result;
+       struct tomoyo_path_info exe;
+       if (!file)
+               return false;
+       exe.name = tomoyo_realpath_from_path(&file->f_path);
+       if (!exe.name)
+               return false;
+       tomoyo_fill_path_info(&exe);
+       result = tomoyo_compare_name_union(&exe, ptr);
+       kfree(exe.name);
+       return result == match;
+}
+
+/**
+ * tomoyo_get_dqword - tomoyo_get_name() for a quoted string.
+ *
+ * @start: String to save.
+ *
+ * Returns pointer to "struct tomoyo_path_info" on success, NULL otherwise.
+ */
+static const struct tomoyo_path_info *tomoyo_get_dqword(char *start)
+{
+       char *cp = start + strlen(start) - 1;
+       if (cp == start || *start++ != '"' || *cp != '"')
+               return NULL;
+       *cp = '\0';
+       if (*start && !tomoyo_correct_word(start))
+               return NULL;
+       return tomoyo_get_name(start);
+}
+
+/**
+ * tomoyo_parse_name_union_quoted - Parse a quoted word.
+ *
+ * @param: Pointer to "struct tomoyo_acl_param".
+ * @ptr:   Pointer to "struct tomoyo_name_union".
+ *
+ * Returns true on success, false otherwise.
+ */
+static bool tomoyo_parse_name_union_quoted(struct tomoyo_acl_param *param,
+                                          struct tomoyo_name_union *ptr)
+{
+       char *filename = param->data;
+       if (*filename == '@')
+               return tomoyo_parse_name_union(param, ptr);
+       ptr->filename = tomoyo_get_dqword(filename);
+       return ptr->filename != NULL;
+}
+
+/**
+ * tomoyo_parse_argv - Parse an argv[] condition part.
+ *
+ * @left:  Lefthand value.
+ * @right: Righthand value.
+ * @argv:  Pointer to "struct tomoyo_argv".
+ *
+ * Returns true on success, false otherwise.
+ */
+static bool tomoyo_parse_argv(char *left, char *right,
+                             struct tomoyo_argv *argv)
+{
+       if (tomoyo_parse_ulong(&argv->index, &left) !=
+           TOMOYO_VALUE_TYPE_DECIMAL || *left++ != ']' || *left)
+               return false;
+       argv->value = tomoyo_get_dqword(right);
+       return argv->value != NULL;
+}
+
+/**
+ * tomoyo_parse_envp - Parse an envp[] condition part.
+ *
+ * @left:  Lefthand value.
+ * @right: Righthand value.
+ * @envp:  Pointer to "struct tomoyo_envp".
+ *
+ * Returns true on success, false otherwise.
+ */
+static bool tomoyo_parse_envp(char *left, char *right,
+                             struct tomoyo_envp *envp)
+{
+       const struct tomoyo_path_info *name;
+       const struct tomoyo_path_info *value;
+       char *cp = left + strlen(left) - 1;
+       if (*cp-- != ']' || *cp != '"')
+               goto out;
+       *cp = '\0';
+       if (!tomoyo_correct_word(left))
+               goto out;
+       name = tomoyo_get_name(left);
+       if (!name)
+               goto out;
+       if (!strcmp(right, "NULL")) {
+               value = NULL;
+       } else {
+               value = tomoyo_get_dqword(right);
+               if (!value) {
+                       tomoyo_put_name(name);
+                       goto out;
+               }
+       }
+       envp->name = name;
+       envp->value = value;
+       return true;
+out:
+       return false;
+}
+
+/**
+ * tomoyo_same_condition - Check for duplicated "struct tomoyo_condition" entry.
+ *
+ * @a: Pointer to "struct tomoyo_condition".
+ * @b: Pointer to "struct tomoyo_condition".
+ *
+ * Returns true if @a == @b, false otherwise.
+ */
+static inline bool tomoyo_same_condition(const struct tomoyo_condition *a,
+                                        const struct tomoyo_condition *b)
+{
+       return a->size == b->size && a->condc == b->condc &&
+               a->numbers_count == b->numbers_count &&
+               a->names_count == b->names_count &&
+               a->argc == b->argc && a->envc == b->envc &&
+               a->grant_log == b->grant_log && a->transit == b->transit &&
+               !memcmp(a + 1, b + 1, a->size - sizeof(*a));
+}
+
+/**
+ * tomoyo_condition_type - Get condition type.
+ *
+ * @word: Keyword string.
+ *
+ * Returns one of values in "enum tomoyo_conditions_index" on success,
+ * TOMOYO_MAX_CONDITION_KEYWORD otherwise.
+ */
+static u8 tomoyo_condition_type(const char *word)
+{
+       u8 i;
+       for (i = 0; i < TOMOYO_MAX_CONDITION_KEYWORD; i++) {
+               if (!strcmp(word, tomoyo_condition_keyword[i]))
+                       break;
+       }
+       return i;
+}
+
+/* Define this to enable debug mode. */
+/* #define DEBUG_CONDITION */
+
+#ifdef DEBUG_CONDITION
+#define dprintk printk
+#else
+#define dprintk(...) do { } while (0)
+#endif
+
+/**
+ * tomoyo_commit_condition - Commit "struct tomoyo_condition".
+ *
+ * @entry: Pointer to "struct tomoyo_condition".
+ *
+ * Returns pointer to "struct tomoyo_condition" on success, NULL otherwise.
+ *
+ * This function merges duplicated entries. This function returns NULL if
+ * @entry is not duplicated but memory quota for policy has exceeded.
+ */
+static struct tomoyo_condition *tomoyo_commit_condition
+(struct tomoyo_condition *entry)
+{
+       struct tomoyo_condition *ptr;
+       bool found = false;
+       if (mutex_lock_interruptible(&tomoyo_policy_lock)) {
+               dprintk(KERN_WARNING "%u: %s failed\n", __LINE__, __func__);
+               ptr = NULL;
+               found = true;
+               goto out;
+       }
+       list_for_each_entry(ptr, &tomoyo_condition_list, head.list) {
+               if (!tomoyo_same_condition(ptr, entry) ||
+                   atomic_read(&ptr->head.users) == TOMOYO_GC_IN_PROGRESS)
+                       continue;
+               /* Same entry found. Share this entry. */
+               atomic_inc(&ptr->head.users);
+               found = true;
+               break;
+       }
+       if (!found) {
+               if (tomoyo_memory_ok(entry)) {
+                       atomic_set(&entry->head.users, 1);
+                       list_add(&entry->head.list, &tomoyo_condition_list);
+               } else {
+                       found = true;
+                       ptr = NULL;
+               }
+       }
+       mutex_unlock(&tomoyo_policy_lock);
+out:
+       if (found) {
+               tomoyo_del_condition(&entry->head.list);
+               kfree(entry);
+               entry = ptr;
+       }
+       return entry;
+}
+
+/**
+ * tomoyo_get_transit_preference - Parse domain transition preference for execve().
+ *
+ * @param: Pointer to "struct tomoyo_acl_param".
+ * @e:     Pointer to "struct tomoyo_condition".
+ *
+ * Returns the condition string part.
+ */
+static char *tomoyo_get_transit_preference(struct tomoyo_acl_param *param,
+                                          struct tomoyo_condition *e)
+{
+       char * const pos = param->data;
+       bool flag;
+       if (*pos == '<') {
+               e->transit = tomoyo_get_domainname(param);
+               goto done;
+       }
+       {
+               char *cp = strchr(pos, ' ');
+               if (cp)
+                       *cp = '\0';
+               flag = tomoyo_correct_path(pos) || !strcmp(pos, "keep") ||
+                       !strcmp(pos, "initialize") || !strcmp(pos, "reset") ||
+                       !strcmp(pos, "child") || !strcmp(pos, "parent");
+               if (cp)
+                       *cp = ' ';
+       }
+       if (!flag)
+               return pos;
+       e->transit = tomoyo_get_name(tomoyo_read_token(param));
+done:
+       if (e->transit)
+               return param->data;
+       /*
+        * Return a bad read-only condition string that will let
+        * tomoyo_get_condition() return NULL.
+        */
+       return "/";
+}
+
+/**
+ * tomoyo_get_condition - Parse condition part.
+ *
+ * @param: Pointer to "struct tomoyo_acl_param".
+ *
+ * Returns pointer to "struct tomoyo_condition" on success, NULL otherwise.
+ */
+struct tomoyo_condition *tomoyo_get_condition(struct tomoyo_acl_param *param)
+{
+       struct tomoyo_condition *entry = NULL;
+       struct tomoyo_condition_element *condp = NULL;
+       struct tomoyo_number_union *numbers_p = NULL;
+       struct tomoyo_name_union *names_p = NULL;
+       struct tomoyo_argv *argv = NULL;
+       struct tomoyo_envp *envp = NULL;
+       struct tomoyo_condition e = { };
+       char * const start_of_string =
+               tomoyo_get_transit_preference(param, &e);
+       char * const end_of_string = start_of_string + strlen(start_of_string);
+       char *pos;
+rerun:
+       pos = start_of_string;
+       while (1) {
+               u8 left = -1;
+               u8 right = -1;
+               char *left_word = pos;
+               char *cp;
+               char *right_word;
+               bool is_not;
+               if (!*left_word)
+                       break;
+               /*
+                * Since left-hand condition does not allow use of "path_group"
+                * or "number_group" and environment variable's names do not
+                * accept '=', it is guaranteed that the original line consists
+                * of one or more repetition of $left$operator$right blocks
+                * where "$left is free from '=' and ' '" and "$operator is
+                * either '=' or '!='" and "$right is free from ' '".
+                * Therefore, we can reconstruct the original line at the end
+                * of dry run even if we overwrite $operator with '\0'.
+                */
+               cp = strchr(pos, ' ');
+               if (cp) {
+                       *cp = '\0'; /* Will restore later. */
+                       pos = cp + 1;
+               } else {
+                       pos = "";
+               }
+               right_word = strchr(left_word, '=');
+               if (!right_word || right_word == left_word)
+                       goto out;
+               is_not = *(right_word - 1) == '!';
+               if (is_not)
+                       *(right_word++ - 1) = '\0'; /* Will restore later. */
+               else if (*(right_word + 1) != '=')
+                       *right_word++ = '\0'; /* Will restore later. */
+               else
+                       goto out;
+               dprintk(KERN_WARNING "%u: <%s>%s=<%s>\n", __LINE__, left_word,
+                       is_not ? "!" : "", right_word);
+               if (!strcmp(left_word, "grant_log")) {
+                       if (entry) {
+                               if (is_not ||
+                                   entry->grant_log != TOMOYO_GRANTLOG_AUTO)
+                                       goto out;
+                               else if (!strcmp(right_word, "yes"))
+                                       entry->grant_log = TOMOYO_GRANTLOG_YES;
+                               else if (!strcmp(right_word, "no"))
+                                       entry->grant_log = TOMOYO_GRANTLOG_NO;
+                               else
+                                       goto out;
+                       }
+                       continue;
+               }
+               if (!strncmp(left_word, "exec.argv[", 10)) {
+                       if (!argv) {
+                               e.argc++;
+                               e.condc++;
+                       } else {
+                               e.argc--;
+                               e.condc--;
+                               left = TOMOYO_ARGV_ENTRY;
+                               argv->is_not = is_not;
+                               if (!tomoyo_parse_argv(left_word + 10,
+                                                      right_word, argv++))
+                                       goto out;
+                       }
+                       goto store_value;
+               }
+               if (!strncmp(left_word, "exec.envp[\"", 11)) {
+                       if (!envp) {
+                               e.envc++;
+                               e.condc++;
+                       } else {
+                               e.envc--;
+                               e.condc--;
+                               left = TOMOYO_ENVP_ENTRY;
+                               envp->is_not = is_not;
+                               if (!tomoyo_parse_envp(left_word + 11,
+                                                      right_word, envp++))
+                                       goto out;
+                       }
+                       goto store_value;
+               }
+               left = tomoyo_condition_type(left_word);
+               dprintk(KERN_WARNING "%u: <%s> left=%u\n", __LINE__, left_word,
+                       left);
+               if (left == TOMOYO_MAX_CONDITION_KEYWORD) {
+                       if (!numbers_p) {
+                               e.numbers_count++;
+                       } else {
+                               e.numbers_count--;
+                               left = TOMOYO_NUMBER_UNION;
+                               param->data = left_word;
+                               if (*left_word == '@' ||
+                                   !tomoyo_parse_number_union(param,
+                                                              numbers_p++))
+                                       goto out;
+                       }
+               }
+               if (!condp)
+                       e.condc++;
+               else
+                       e.condc--;
+               if (left == TOMOYO_EXEC_REALPATH ||
+                   left == TOMOYO_SYMLINK_TARGET) {
+                       if (!names_p) {
+                               e.names_count++;
+                       } else {
+                               e.names_count--;
+                               right = TOMOYO_NAME_UNION;
+                               param->data = right_word;
+                               if (!tomoyo_parse_name_union_quoted(param,
+                                                                   names_p++))
+                                       goto out;
+                       }
+                       goto store_value;
+               }
+               right = tomoyo_condition_type(right_word);
+               if (right == TOMOYO_MAX_CONDITION_KEYWORD) {
+                       if (!numbers_p) {
+                               e.numbers_count++;
+                       } else {
+                               e.numbers_count--;
+                               right = TOMOYO_NUMBER_UNION;
+                               param->data = right_word;
+                               if (!tomoyo_parse_number_union(param,
+                                                              numbers_p++))
+                                       goto out;
+                       }
+               }
+store_value:
+               if (!condp) {
+                       dprintk(KERN_WARNING "%u: dry_run left=%u right=%u "
+                               "match=%u\n", __LINE__, left, right, !is_not);
+                       continue;
+               }
+               condp->left = left;
+               condp->right = right;
+               condp->equals = !is_not;
+               dprintk(KERN_WARNING "%u: left=%u right=%u match=%u\n",
+                       __LINE__, condp->left, condp->right,
+                       condp->equals);
+               condp++;
+       }
+       dprintk(KERN_INFO "%u: cond=%u numbers=%u names=%u ac=%u ec=%u\n",
+               __LINE__, e.condc, e.numbers_count, e.names_count, e.argc,
+               e.envc);
+       if (entry) {
+               BUG_ON(e.names_count | e.numbers_count | e.argc | e.envc |
+                      e.condc);
+               return tomoyo_commit_condition(entry);
+       }
+       e.size = sizeof(*entry)
+               + e.condc * sizeof(struct tomoyo_condition_element)
+               + e.numbers_count * sizeof(struct tomoyo_number_union)
+               + e.names_count * sizeof(struct tomoyo_name_union)
+               + e.argc * sizeof(struct tomoyo_argv)
+               + e.envc * sizeof(struct tomoyo_envp);
+       entry = kzalloc(e.size, GFP_NOFS);
+       if (!entry)
+               goto out2;
+       *entry = e;
+       e.transit = NULL;
+       condp = (struct tomoyo_condition_element *) (entry + 1);
+       numbers_p = (struct tomoyo_number_union *) (condp + e.condc);
+       names_p = (struct tomoyo_name_union *) (numbers_p + e.numbers_count);
+       argv = (struct tomoyo_argv *) (names_p + e.names_count);
+       envp = (struct tomoyo_envp *) (argv + e.argc);
+       {
+               bool flag = false;
+               for (pos = start_of_string; pos < end_of_string; pos++) {
+                       if (*pos)
+                               continue;
+                       if (flag) /* Restore " ". */
+                               *pos = ' ';
+                       else if (*(pos + 1) == '=') /* Restore "!=". */
+                               *pos = '!';
+                       else /* Restore "=". */
+                               *pos = '=';
+                       flag = !flag;
+               }
+       }
+       goto rerun;
+out:
+       dprintk(KERN_WARNING "%u: %s failed\n", __LINE__, __func__);
+       if (entry) {
+               tomoyo_del_condition(&entry->head.list);
+               kfree(entry);
+       }
+out2:
+       tomoyo_put_name(e.transit);
+       return NULL;
+}
+
+/**
+ * tomoyo_get_attributes - Revalidate "struct inode".
+ *
+ * @obj: Pointer to "struct tomoyo_obj_info".
+ *
+ * Returns nothing.
+ */
+void tomoyo_get_attributes(struct tomoyo_obj_info *obj)
+{
+       u8 i;
+       struct dentry *dentry = NULL;
+
+       for (i = 0; i < TOMOYO_MAX_PATH_STAT; i++) {
+               struct inode *inode;
+               switch (i) {
+               case TOMOYO_PATH1:
+                       dentry = obj->path1.dentry;
+                       if (!dentry)
+                               continue;
+                       break;
+               case TOMOYO_PATH2:
+                       dentry = obj->path2.dentry;
+                       if (!dentry)
+                               continue;
+                       break;
+               default:
+                       if (!dentry)
+                               continue;
+                       dentry = dget_parent(dentry);
+                       break;
+               }
+               inode = d_backing_inode(dentry);
+               if (inode) {
+                       struct tomoyo_mini_stat *stat = &obj->stat[i];
+                       stat->uid  = inode->i_uid;
+                       stat->gid  = inode->i_gid;
+                       stat->ino  = inode->i_ino;
+                       stat->mode = inode->i_mode;
+                       stat->dev  = inode->i_sb->s_dev;
+                       stat->rdev = inode->i_rdev;
+                       obj->stat_valid[i] = true;
+               }
+               if (i & 1) /* i == TOMOYO_PATH1_PARENT ||
+                             i == TOMOYO_PATH2_PARENT */
+                       dput(dentry);
+       }
+}
+
+/**
+ * tomoyo_condition - Check condition part.
+ *
+ * @r:    Pointer to "struct tomoyo_request_info".
+ * @cond: Pointer to "struct tomoyo_condition". Maybe NULL.
+ *
+ * Returns true on success, false otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
+ */
+bool tomoyo_condition(struct tomoyo_request_info *r,
+                     const struct tomoyo_condition *cond)
+{
+       u32 i;
+       unsigned long min_v[2] = { 0, 0 };
+       unsigned long max_v[2] = { 0, 0 };
+       const struct tomoyo_condition_element *condp;
+       const struct tomoyo_number_union *numbers_p;
+       const struct tomoyo_name_union *names_p;
+       const struct tomoyo_argv *argv;
+       const struct tomoyo_envp *envp;
+       struct tomoyo_obj_info *obj;
+       u16 condc;
+       u16 argc;
+       u16 envc;
+       struct linux_binprm *bprm = NULL;
+       if (!cond)
+               return true;
+       condc = cond->condc;
+       argc = cond->argc;
+       envc = cond->envc;
+       obj = r->obj;
+       if (r->ee)
+               bprm = r->ee->bprm;
+       if (!bprm && (argc || envc))
+               return false;
+       condp = (struct tomoyo_condition_element *) (cond + 1);
+       numbers_p = (const struct tomoyo_number_union *) (condp + condc);
+       names_p = (const struct tomoyo_name_union *)
+               (numbers_p + cond->numbers_count);
+       argv = (const struct tomoyo_argv *) (names_p + cond->names_count);
+       envp = (const struct tomoyo_envp *) (argv + argc);
+       for (i = 0; i < condc; i++) {
+               const bool match = condp->equals;
+               const u8 left = condp->left;
+               const u8 right = condp->right;
+               bool is_bitop[2] = { false, false };
+               u8 j;
+               condp++;
+               /* Check argv[] and envp[] later. */
+               if (left == TOMOYO_ARGV_ENTRY || left == TOMOYO_ENVP_ENTRY)
+                       continue;
+               /* Check string expressions. */
+               if (right == TOMOYO_NAME_UNION) {
+                       const struct tomoyo_name_union *ptr = names_p++;
+                       switch (left) {
+                               struct tomoyo_path_info *symlink;
+                               struct tomoyo_execve *ee;
+                               struct file *file;
+                       case TOMOYO_SYMLINK_TARGET:
+                               symlink = obj ? obj->symlink_target : NULL;
+                               if (!symlink ||
+                                   !tomoyo_compare_name_union(symlink, ptr)
+                                   == match)
+                                       goto out;
+                               break;
+                       case TOMOYO_EXEC_REALPATH:
+                               ee = r->ee;
+                               file = ee ? ee->bprm->file : NULL;
+                               if (!tomoyo_scan_exec_realpath(file, ptr,
+                                                              match))
+                                       goto out;
+                               break;
+                       }
+                       continue;
+               }
+               /* Check numeric or bit-op expressions. */
+               for (j = 0; j < 2; j++) {
+                       const u8 index = j ? right : left;
+                       unsigned long value = 0;
+                       switch (index) {
+                       case TOMOYO_TASK_UID:
+                               value = from_kuid(&init_user_ns, current_uid());
+                               break;
+                       case TOMOYO_TASK_EUID:
+                               value = from_kuid(&init_user_ns, current_euid());
+                               break;
+                       case TOMOYO_TASK_SUID:
+                               value = from_kuid(&init_user_ns, current_suid());
+                               break;
+                       case TOMOYO_TASK_FSUID:
+                               value = from_kuid(&init_user_ns, current_fsuid());
+                               break;
+                       case TOMOYO_TASK_GID:
+                               value = from_kgid(&init_user_ns, current_gid());
+                               break;
+                       case TOMOYO_TASK_EGID:
+                               value = from_kgid(&init_user_ns, current_egid());
+                               break;
+                       case TOMOYO_TASK_SGID:
+                               value = from_kgid(&init_user_ns, current_sgid());
+                               break;
+                       case TOMOYO_TASK_FSGID:
+                               value = from_kgid(&init_user_ns, current_fsgid());
+                               break;
+                       case TOMOYO_TASK_PID:
+                               value = tomoyo_sys_getpid();
+                               break;
+                       case TOMOYO_TASK_PPID:
+                               value = tomoyo_sys_getppid();
+                               break;
+                       case TOMOYO_TYPE_IS_SOCKET:
+                               value = S_IFSOCK;
+                               break;
+                       case TOMOYO_TYPE_IS_SYMLINK:
+                               value = S_IFLNK;
+                               break;
+                       case TOMOYO_TYPE_IS_FILE:
+                               value = S_IFREG;
+                               break;
+                       case TOMOYO_TYPE_IS_BLOCK_DEV:
+                               value = S_IFBLK;
+                               break;
+                       case TOMOYO_TYPE_IS_DIRECTORY:
+                               value = S_IFDIR;
+                               break;
+                       case TOMOYO_TYPE_IS_CHAR_DEV:
+                               value = S_IFCHR;
+                               break;
+                       case TOMOYO_TYPE_IS_FIFO:
+                               value = S_IFIFO;
+                               break;
+                       case TOMOYO_MODE_SETUID:
+                               value = S_ISUID;
+                               break;
+                       case TOMOYO_MODE_SETGID:
+                               value = S_ISGID;
+                               break;
+                       case TOMOYO_MODE_STICKY:
+                               value = S_ISVTX;
+                               break;
+                       case TOMOYO_MODE_OWNER_READ:
+                               value = S_IRUSR;
+                               break;
+                       case TOMOYO_MODE_OWNER_WRITE:
+                               value = S_IWUSR;
+                               break;
+                       case TOMOYO_MODE_OWNER_EXECUTE:
+                               value = S_IXUSR;
+                               break;
+                       case TOMOYO_MODE_GROUP_READ:
+                               value = S_IRGRP;
+                               break;
+                       case TOMOYO_MODE_GROUP_WRITE:
+                               value = S_IWGRP;
+                               break;
+                       case TOMOYO_MODE_GROUP_EXECUTE:
+                               value = S_IXGRP;
+                               break;
+                       case TOMOYO_MODE_OTHERS_READ:
+                               value = S_IROTH;
+                               break;
+                       case TOMOYO_MODE_OTHERS_WRITE:
+                               value = S_IWOTH;
+                               break;
+                       case TOMOYO_MODE_OTHERS_EXECUTE:
+                               value = S_IXOTH;
+                               break;
+                       case TOMOYO_EXEC_ARGC:
+                               if (!bprm)
+                                       goto out;
+                               value = bprm->argc;
+                               break;
+                       case TOMOYO_EXEC_ENVC:
+                               if (!bprm)
+                                       goto out;
+                               value = bprm->envc;
+                               break;
+                       case TOMOYO_NUMBER_UNION:
+                               /* Fetch values later. */
+                               break;
+                       default:
+                               if (!obj)
+                                       goto out;
+                               if (!obj->validate_done) {
+                                       tomoyo_get_attributes(obj);
+                                       obj->validate_done = true;
+                               }
+                               {
+                                       u8 stat_index;
+                                       struct tomoyo_mini_stat *stat;
+                                       switch (index) {
+                                       case TOMOYO_PATH1_UID:
+                                       case TOMOYO_PATH1_GID:
+                                       case TOMOYO_PATH1_INO:
+                                       case TOMOYO_PATH1_MAJOR:
+                                       case TOMOYO_PATH1_MINOR:
+                                       case TOMOYO_PATH1_TYPE:
+                                       case TOMOYO_PATH1_DEV_MAJOR:
+                                       case TOMOYO_PATH1_DEV_MINOR:
+                                       case TOMOYO_PATH1_PERM:
+                                               stat_index = TOMOYO_PATH1;
+                                               break;
+                                       case TOMOYO_PATH2_UID:
+                                       case TOMOYO_PATH2_GID:
+                                       case TOMOYO_PATH2_INO:
+                                       case TOMOYO_PATH2_MAJOR:
+                                       case TOMOYO_PATH2_MINOR:
+                                       case TOMOYO_PATH2_TYPE:
+                                       case TOMOYO_PATH2_DEV_MAJOR:
+                                       case TOMOYO_PATH2_DEV_MINOR:
+                                       case TOMOYO_PATH2_PERM:
+                                               stat_index = TOMOYO_PATH2;
+                                               break;
+                                       case TOMOYO_PATH1_PARENT_UID:
+                                       case TOMOYO_PATH1_PARENT_GID:
+                                       case TOMOYO_PATH1_PARENT_INO:
+                                       case TOMOYO_PATH1_PARENT_PERM:
+                                               stat_index =
+                                                       TOMOYO_PATH1_PARENT;
+                                               break;
+                                       case TOMOYO_PATH2_PARENT_UID:
+                                       case TOMOYO_PATH2_PARENT_GID:
+                                       case TOMOYO_PATH2_PARENT_INO:
+                                       case TOMOYO_PATH2_PARENT_PERM:
+                                               stat_index =
+                                                       TOMOYO_PATH2_PARENT;
+                                               break;
+                                       default:
+                                               goto out;
+                                       }
+                                       if (!obj->stat_valid[stat_index])
+                                               goto out;
+                                       stat = &obj->stat[stat_index];
+                                       switch (index) {
+                                       case TOMOYO_PATH1_UID:
+                                       case TOMOYO_PATH2_UID:
+                                       case TOMOYO_PATH1_PARENT_UID:
+                                       case TOMOYO_PATH2_PARENT_UID:
+                                               value = from_kuid(&init_user_ns, stat->uid);
+                                               break;
+                                       case TOMOYO_PATH1_GID:
+                                       case TOMOYO_PATH2_GID:
+                                       case TOMOYO_PATH1_PARENT_GID:
+                                       case TOMOYO_PATH2_PARENT_GID:
+                                               value = from_kgid(&init_user_ns, stat->gid);
+                                               break;
+                                       case TOMOYO_PATH1_INO:
+                                       case TOMOYO_PATH2_INO:
+                                       case TOMOYO_PATH1_PARENT_INO:
+                                       case TOMOYO_PATH2_PARENT_INO:
+                                               value = stat->ino;
+                                               break;
+                                       case TOMOYO_PATH1_MAJOR:
+                                       case TOMOYO_PATH2_MAJOR:
+                                               value = MAJOR(stat->dev);
+                                               break;
+                                       case TOMOYO_PATH1_MINOR:
+                                       case TOMOYO_PATH2_MINOR:
+                                               value = MINOR(stat->dev);
+                                               break;
+                                       case TOMOYO_PATH1_TYPE:
+                                       case TOMOYO_PATH2_TYPE:
+                                               value = stat->mode & S_IFMT;
+                                               break;
+                                       case TOMOYO_PATH1_DEV_MAJOR:
+                                       case TOMOYO_PATH2_DEV_MAJOR:
+                                               value = MAJOR(stat->rdev);
+                                               break;
+                                       case TOMOYO_PATH1_DEV_MINOR:
+                                       case TOMOYO_PATH2_DEV_MINOR:
+                                               value = MINOR(stat->rdev);
+                                               break;
+                                       case TOMOYO_PATH1_PERM:
+                                       case TOMOYO_PATH2_PERM:
+                                       case TOMOYO_PATH1_PARENT_PERM:
+                                       case TOMOYO_PATH2_PARENT_PERM:
+                                               value = stat->mode & S_IALLUGO;
+                                               break;
+                                       }
+                               }
+                               break;
+                       }
+                       max_v[j] = value;
+                       min_v[j] = value;
+                       switch (index) {
+                       case TOMOYO_MODE_SETUID:
+                       case TOMOYO_MODE_SETGID:
+                       case TOMOYO_MODE_STICKY:
+                       case TOMOYO_MODE_OWNER_READ:
+                       case TOMOYO_MODE_OWNER_WRITE:
+                       case TOMOYO_MODE_OWNER_EXECUTE:
+                       case TOMOYO_MODE_GROUP_READ:
+                       case TOMOYO_MODE_GROUP_WRITE:
+                       case TOMOYO_MODE_GROUP_EXECUTE:
+                       case TOMOYO_MODE_OTHERS_READ:
+                       case TOMOYO_MODE_OTHERS_WRITE:
+                       case TOMOYO_MODE_OTHERS_EXECUTE:
+                               is_bitop[j] = true;
+                       }
+               }
+               if (left == TOMOYO_NUMBER_UNION) {
+                       /* Fetch values now. */
+                       const struct tomoyo_number_union *ptr = numbers_p++;
+                       min_v[0] = ptr->values[0];
+                       max_v[0] = ptr->values[1];
+               }
+               if (right == TOMOYO_NUMBER_UNION) {
+                       /* Fetch values now. */
+                       const struct tomoyo_number_union *ptr = numbers_p++;
+                       if (ptr->group) {
+                               if (tomoyo_number_matches_group(min_v[0],
+                                                               max_v[0],
+                                                               ptr->group)
+                                   == match)
+                                       continue;
+                       } else {
+                               if ((min_v[0] <= ptr->values[1] &&
+                                    max_v[0] >= ptr->values[0]) == match)
+                                       continue;
+                       }
+                       goto out;
+               }
+               /*
+                * Bit operation is valid only when counterpart value
+                * represents permission.
+                */
+               if (is_bitop[0] && is_bitop[1]) {
+                       goto out;
+               } else if (is_bitop[0]) {
+                       switch (right) {
+                       case TOMOYO_PATH1_PERM:
+                       case TOMOYO_PATH1_PARENT_PERM:
+                       case TOMOYO_PATH2_PERM:
+                       case TOMOYO_PATH2_PARENT_PERM:
+                               if (!(max_v[0] & max_v[1]) == !match)
+                                       continue;
+                       }
+                       goto out;
+               } else if (is_bitop[1]) {
+                       switch (left) {
+                       case TOMOYO_PATH1_PERM:
+                       case TOMOYO_PATH1_PARENT_PERM:
+                       case TOMOYO_PATH2_PERM:
+                       case TOMOYO_PATH2_PARENT_PERM:
+                               if (!(max_v[0] & max_v[1]) == !match)
+                                       continue;
+                       }
+                       goto out;
+               }
+               /* Normal value range comparison. */
+               if ((min_v[0] <= max_v[1] && max_v[0] >= min_v[1]) == match)
+                       continue;
+out:
+               return false;
+       }
+       /* Check argv[] and envp[] now. */
+       if (r->ee && (argc || envc))
+               return tomoyo_scan_bprm(r->ee, argc, argv, envc, envp);
+       return true;
+}