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@@ -0,0 +1,349 @@
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+/*
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+ * security/tomoyo/condition.c
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+ *
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+ * Copyright (C) 2005-2011 NTT DATA CORPORATION
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+ */
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+
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+#include "common.h"
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+#include <linux/slab.h>
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+
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+/* List of "struct tomoyo_condition". */
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+LIST_HEAD(tomoyo_condition_list);
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+
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+/**
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+ * tomoyo_same_condition - Check for duplicated "struct tomoyo_condition" entry.
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+ *
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+ * @a: Pointer to "struct tomoyo_condition".
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+ * @b: Pointer to "struct tomoyo_condition".
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+ *
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+ * Returns true if @a == @b, false otherwise.
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+ */
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+static inline bool tomoyo_same_condition(const struct tomoyo_condition *a,
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+ const struct tomoyo_condition *b)
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+{
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+ return a->size == b->size && a->condc == b->condc &&
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+ a->numbers_count == b->numbers_count &&
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+ !memcmp(a + 1, b + 1, a->size - sizeof(*a));
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+}
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+
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+/**
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+ * tomoyo_condition_type - Get condition type.
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+ *
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+ * @word: Keyword string.
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+ *
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+ * Returns one of values in "enum tomoyo_conditions_index" on success,
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+ * TOMOYO_MAX_CONDITION_KEYWORD otherwise.
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+ */
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+static u8 tomoyo_condition_type(const char *word)
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+{
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+ u8 i;
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+ for (i = 0; i < TOMOYO_MAX_CONDITION_KEYWORD; i++) {
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+ if (!strcmp(word, tomoyo_condition_keyword[i]))
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+ break;
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+ }
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+ return i;
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+}
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+
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+/* Define this to enable debug mode. */
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+/* #define DEBUG_CONDITION */
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+
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+#ifdef DEBUG_CONDITION
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+#define dprintk printk
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+#else
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+#define dprintk(...) do { } while (0)
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+#endif
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+
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+/**
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+ * tomoyo_commit_condition - Commit "struct tomoyo_condition".
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+ *
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+ * @entry: Pointer to "struct tomoyo_condition".
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+ *
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+ * Returns pointer to "struct tomoyo_condition" on success, NULL otherwise.
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+ *
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+ * This function merges duplicated entries. This function returns NULL if
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+ * @entry is not duplicated but memory quota for policy has exceeded.
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+ */
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+static struct tomoyo_condition *tomoyo_commit_condition
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+(struct tomoyo_condition *entry)
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+{
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+ struct tomoyo_condition *ptr;
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+ bool found = false;
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+ if (mutex_lock_interruptible(&tomoyo_policy_lock)) {
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+ dprintk(KERN_WARNING "%u: %s failed\n", __LINE__, __func__);
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+ ptr = NULL;
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+ found = true;
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+ goto out;
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+ }
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+ list_for_each_entry_rcu(ptr, &tomoyo_condition_list, head.list) {
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+ if (!tomoyo_same_condition(ptr, entry))
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+ continue;
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+ /* Same entry found. Share this entry. */
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+ atomic_inc(&ptr->head.users);
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+ found = true;
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+ break;
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+ }
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+ if (!found) {
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+ if (tomoyo_memory_ok(entry)) {
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+ atomic_set(&entry->head.users, 1);
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+ list_add_rcu(&entry->head.list,
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+ &tomoyo_condition_list);
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+ } else {
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+ found = true;
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+ ptr = NULL;
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+ }
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+ }
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+ mutex_unlock(&tomoyo_policy_lock);
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+out:
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+ if (found) {
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+ tomoyo_del_condition(&entry->head.list);
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+ kfree(entry);
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+ entry = ptr;
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+ }
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+ return entry;
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+}
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+
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+/**
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+ * tomoyo_get_condition - Parse condition part.
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+ *
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+ * @param: Pointer to "struct tomoyo_acl_param".
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+ *
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+ * Returns pointer to "struct tomoyo_condition" on success, NULL otherwise.
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+ */
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+struct tomoyo_condition *tomoyo_get_condition(struct tomoyo_acl_param *param)
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+{
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+ struct tomoyo_condition *entry = NULL;
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+ struct tomoyo_condition_element *condp = NULL;
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+ struct tomoyo_number_union *numbers_p = NULL;
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+ struct tomoyo_condition e = { };
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+ char * const start_of_string = param->data;
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+ char * const end_of_string = start_of_string + strlen(start_of_string);
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+ char *pos;
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+rerun:
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+ pos = start_of_string;
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+ while (1) {
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+ u8 left = -1;
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+ u8 right = -1;
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+ char *left_word = pos;
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+ char *cp;
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+ char *right_word;
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+ bool is_not;
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+ if (!*left_word)
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+ break;
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+ /*
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+ * Since left-hand condition does not allow use of "path_group"
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+ * or "number_group" and environment variable's names do not
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+ * accept '=', it is guaranteed that the original line consists
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+ * of one or more repetition of $left$operator$right blocks
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+ * where "$left is free from '=' and ' '" and "$operator is
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+ * either '=' or '!='" and "$right is free from ' '".
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+ * Therefore, we can reconstruct the original line at the end
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+ * of dry run even if we overwrite $operator with '\0'.
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+ */
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+ cp = strchr(pos, ' ');
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+ if (cp) {
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+ *cp = '\0'; /* Will restore later. */
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+ pos = cp + 1;
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+ } else {
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+ pos = "";
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+ }
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+ right_word = strchr(left_word, '=');
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+ if (!right_word || right_word == left_word)
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+ goto out;
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+ is_not = *(right_word - 1) == '!';
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+ if (is_not)
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+ *(right_word++ - 1) = '\0'; /* Will restore later. */
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+ else if (*(right_word + 1) != '=')
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+ *right_word++ = '\0'; /* Will restore later. */
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+ else
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+ goto out;
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+ dprintk(KERN_WARNING "%u: <%s>%s=<%s>\n", __LINE__, left_word,
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+ is_not ? "!" : "", right_word);
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+ left = tomoyo_condition_type(left_word);
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+ dprintk(KERN_WARNING "%u: <%s> left=%u\n", __LINE__, left_word,
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+ left);
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+ if (left == TOMOYO_MAX_CONDITION_KEYWORD) {
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+ if (!numbers_p) {
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+ e.numbers_count++;
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+ } else {
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+ e.numbers_count--;
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+ left = TOMOYO_NUMBER_UNION;
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+ param->data = left_word;
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+ if (*left_word == '@' ||
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+ !tomoyo_parse_number_union(param,
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+ numbers_p++))
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+ goto out;
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+ }
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+ }
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+ if (!condp)
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+ e.condc++;
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+ else
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+ e.condc--;
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+ right = tomoyo_condition_type(right_word);
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+ if (right == TOMOYO_MAX_CONDITION_KEYWORD) {
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+ if (!numbers_p) {
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+ e.numbers_count++;
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+ } else {
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+ e.numbers_count--;
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+ right = TOMOYO_NUMBER_UNION;
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+ param->data = right_word;
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+ if (!tomoyo_parse_number_union(param,
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+ numbers_p++))
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+ goto out;
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+ }
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+ }
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+ if (!condp) {
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+ dprintk(KERN_WARNING "%u: dry_run left=%u right=%u "
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+ "match=%u\n", __LINE__, left, right, !is_not);
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+ continue;
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+ }
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+ condp->left = left;
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+ condp->right = right;
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+ condp->equals = !is_not;
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+ dprintk(KERN_WARNING "%u: left=%u right=%u match=%u\n",
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+ __LINE__, condp->left, condp->right,
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+ condp->equals);
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+ condp++;
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+ }
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+ dprintk(KERN_INFO "%u: cond=%u numbers=%u\n",
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+ __LINE__, e.condc, e.numbers_count);
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+ if (entry) {
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+ BUG_ON(e.numbers_count | e.condc);
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+ return tomoyo_commit_condition(entry);
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+ }
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+ e.size = sizeof(*entry)
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+ + e.condc * sizeof(struct tomoyo_condition_element)
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+ + e.numbers_count * sizeof(struct tomoyo_number_union);
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+ entry = kzalloc(e.size, GFP_NOFS);
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+ if (!entry)
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+ return NULL;
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+ *entry = e;
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+ condp = (struct tomoyo_condition_element *) (entry + 1);
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+ numbers_p = (struct tomoyo_number_union *) (condp + e.condc);
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+ {
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+ bool flag = false;
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+ for (pos = start_of_string; pos < end_of_string; pos++) {
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+ if (*pos)
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+ continue;
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+ if (flag) /* Restore " ". */
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+ *pos = ' ';
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+ else if (*(pos + 1) == '=') /* Restore "!=". */
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+ *pos = '!';
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+ else /* Restore "=". */
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+ *pos = '=';
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+ flag = !flag;
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+ }
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+ }
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+ goto rerun;
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+out:
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+ dprintk(KERN_WARNING "%u: %s failed\n", __LINE__, __func__);
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+ if (entry) {
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+ tomoyo_del_condition(&entry->head.list);
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+ kfree(entry);
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+ }
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+ return NULL;
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+}
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+
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+/**
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+ * tomoyo_condition - Check condition part.
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+ *
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+ * @r: Pointer to "struct tomoyo_request_info".
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+ * @cond: Pointer to "struct tomoyo_condition". Maybe NULL.
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+ *
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+ * Returns true on success, false otherwise.
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+ *
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+ * Caller holds tomoyo_read_lock().
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+ */
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+bool tomoyo_condition(struct tomoyo_request_info *r,
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+ const struct tomoyo_condition *cond)
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+{
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+ u32 i;
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+ unsigned long min_v[2] = { 0, 0 };
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+ unsigned long max_v[2] = { 0, 0 };
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+ const struct tomoyo_condition_element *condp;
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+ const struct tomoyo_number_union *numbers_p;
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+ u16 condc;
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+ if (!cond)
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+ return true;
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+ condc = cond->condc;
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+ condp = (struct tomoyo_condition_element *) (cond + 1);
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+ numbers_p = (const struct tomoyo_number_union *) (condp + condc);
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+ for (i = 0; i < condc; i++) {
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+ const bool match = condp->equals;
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+ const u8 left = condp->left;
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+ const u8 right = condp->right;
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+ u8 j;
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+ condp++;
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+ /* Check numeric or bit-op expressions. */
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+ for (j = 0; j < 2; j++) {
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+ const u8 index = j ? right : left;
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+ unsigned long value = 0;
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+ switch (index) {
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+ case TOMOYO_TASK_UID:
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+ value = current_uid();
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+ break;
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+ case TOMOYO_TASK_EUID:
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+ value = current_euid();
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+ break;
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+ case TOMOYO_TASK_SUID:
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+ value = current_suid();
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+ break;
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+ case TOMOYO_TASK_FSUID:
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+ value = current_fsuid();
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+ break;
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+ case TOMOYO_TASK_GID:
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+ value = current_gid();
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+ break;
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+ case TOMOYO_TASK_EGID:
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+ value = current_egid();
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+ break;
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+ case TOMOYO_TASK_SGID:
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+ value = current_sgid();
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+ break;
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+ case TOMOYO_TASK_FSGID:
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+ value = current_fsgid();
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+ break;
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+ case TOMOYO_TASK_PID:
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+ value = tomoyo_sys_getpid();
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+ break;
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+ case TOMOYO_TASK_PPID:
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+ value = tomoyo_sys_getppid();
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+ break;
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+ case TOMOYO_NUMBER_UNION:
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+ /* Fetch values later. */
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+ break;
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+ default:
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+ break;
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+ }
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+ max_v[j] = value;
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+ min_v[j] = value;
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+ }
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+ if (left == TOMOYO_NUMBER_UNION) {
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+ /* Fetch values now. */
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+ const struct tomoyo_number_union *ptr = numbers_p++;
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+ min_v[0] = ptr->values[0];
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+ max_v[0] = ptr->values[1];
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+ }
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+ if (right == TOMOYO_NUMBER_UNION) {
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+ /* Fetch values now. */
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+ const struct tomoyo_number_union *ptr = numbers_p++;
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+ if (ptr->group) {
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+ if (tomoyo_number_matches_group(min_v[0],
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+ max_v[0],
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+ ptr->group)
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+ == match)
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+ continue;
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+ } else {
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+ if ((min_v[0] <= ptr->values[1] &&
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+ max_v[0] >= ptr->values[0]) == match)
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+ continue;
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+ }
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+ goto out;
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+ }
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+ /* Normal value range comparison. */
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+ if ((min_v[0] <= max_v[1] && max_v[0] >= min_v[1]) == match)
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+ continue;
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+out:
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+ return false;
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+ }
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+ return true;
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+}
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