TOMOYO: Add pathname aggregation support.
This patch allows users to aggregate programs which provide similar
functionality (e.g. /usr/bin/vi and /usr/bin/emacs ).
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/security/tomoyo/common.c b/security/tomoyo/common.c
index 3f94011c..bdf1ed7 100644
--- a/security/tomoyo/common.c
+++ b/security/tomoyo/common.c
@@ -1141,6 +1141,8 @@
if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_NO_INITIALIZE_DOMAIN))
return tomoyo_write_domain_initializer_policy(data, true,
is_delete);
+ if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_AGGREGATOR))
+ return tomoyo_write_aggregator_policy(data, is_delete);
if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_ALIAS))
return tomoyo_write_alias_policy(data, is_delete);
if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_ALLOW_READ))
@@ -1196,6 +1198,8 @@
head->read_var2 = NULL;
head->read_step = 6;
case 6:
+ if (!tomoyo_read_aggregator_policy(head))
+ break;
head->read_var2 = NULL;
head->read_step = 7;
case 7:
diff --git a/security/tomoyo/common.h b/security/tomoyo/common.h
index d1b8d79..54db39a 100644
--- a/security/tomoyo/common.h
+++ b/security/tomoyo/common.h
@@ -46,6 +46,7 @@
};
/* Keywords for ACLs. */
+#define TOMOYO_KEYWORD_AGGREGATOR "aggregator "
#define TOMOYO_KEYWORD_ALIAS "alias "
#define TOMOYO_KEYWORD_ALLOW_MOUNT "allow_mount "
#define TOMOYO_KEYWORD_ALLOW_READ "allow_read "
@@ -593,6 +594,24 @@
};
/*
+ * tomoyo_aggregator_entry is a structure which is used for holding
+ * "aggregator" entries.
+ * It has following fields.
+ *
+ * (1) "list" which is linked to tomoyo_aggregator_list .
+ * (2) "original_name" which is originally requested name.
+ * (3) "aggregated_name" which is name to rewrite.
+ * (4) "is_deleted" is a bool which is true if marked as deleted, false
+ * otherwise.
+ */
+struct tomoyo_aggregator_entry {
+ struct list_head list;
+ const struct tomoyo_path_info *original_name;
+ const struct tomoyo_path_info *aggregated_name;
+ bool is_deleted;
+};
+
+/*
* tomoyo_alias_entry is a structure which is used for holding "alias" entries.
* It has following fields.
*
@@ -693,6 +712,8 @@
const struct tomoyo_number_union *ptr);
bool tomoyo_parse_number_union(char *data, struct tomoyo_number_union *num);
+/* Read "aggregator" entry in exception policy. */
+bool tomoyo_read_aggregator_policy(struct tomoyo_io_buffer *head);
/* Read "alias" entry in exception policy. */
bool tomoyo_read_alias_policy(struct tomoyo_io_buffer *head);
/*
@@ -730,6 +751,8 @@
/* Check permission for mount operation. */
int tomoyo_mount_permission(char *dev_name, struct path *path, char *type,
unsigned long flags, void *data_page);
+/* Create "aggregator" entry in exception policy. */
+int tomoyo_write_aggregator_policy(char *data, const bool is_delete);
/* Create "alias" entry in exception policy. */
int tomoyo_write_alias_policy(char *data, const bool is_delete);
/*
@@ -857,6 +880,7 @@
extern struct list_head tomoyo_number_group_list;
extern struct list_head tomoyo_domain_initializer_list;
extern struct list_head tomoyo_domain_keeper_list;
+extern struct list_head tomoyo_aggregator_list;
extern struct list_head tomoyo_alias_list;
extern struct list_head tomoyo_globally_readable_list;
extern struct list_head tomoyo_pattern_list;
@@ -1036,6 +1060,14 @@
&& p1->program == p2->program;
}
+static inline bool tomoyo_is_same_aggregator_entry
+(const struct tomoyo_aggregator_entry *p1,
+ const struct tomoyo_aggregator_entry *p2)
+{
+ return p1->original_name == p2->original_name &&
+ p1->aggregated_name == p2->aggregated_name;
+}
+
static inline bool tomoyo_is_same_alias_entry
(const struct tomoyo_alias_entry *p1, const struct tomoyo_alias_entry *p2)
{
diff --git a/security/tomoyo/domain.c b/security/tomoyo/domain.c
index 50f6e79..a07ca6d 100644
--- a/security/tomoyo/domain.c
+++ b/security/tomoyo/domain.c
@@ -483,6 +483,136 @@
}
/*
+ * tomoyo_aggregator_list is used for holding list of rewrite table for
+ * execve() request. Some programs provides similar functionality. This keyword
+ * allows users to aggregate such programs.
+ *
+ * Entries are added by
+ *
+ * # echo 'aggregator /usr/bin/vi /./editor' > \
+ * /sys/kernel/security/tomoyo/exception_policy
+ * # echo 'aggregator /usr/bin/emacs /./editor' > \
+ * /sys/kernel/security/tomoyo/exception_policy
+ *
+ * and are deleted by
+ *
+ * # echo 'delete aggregator /usr/bin/vi /./editor' > \
+ * /sys/kernel/security/tomoyo/exception_policy
+ * # echo 'delete aggregator /usr/bin/emacs /./editor' > \
+ * /sys/kernel/security/tomoyo/exception_policy
+ *
+ * and all entries are retrieved by
+ *
+ * # grep ^aggregator /sys/kernel/security/tomoyo/exception_policy
+ *
+ * In the example above, if /usr/bin/vi or /usr/bin/emacs are executed,
+ * permission is checked for /./editor and domainname which the current process
+ * will belong to after execve() succeeds is calculated using /./editor .
+ */
+LIST_HEAD(tomoyo_aggregator_list);
+
+/**
+ * tomoyo_update_aggregator_entry - Update "struct tomoyo_aggregator_entry" list.
+ *
+ * @original_name: The original program's name.
+ * @aggregated_name: The program name to use.
+ * @is_delete: True if it is a delete request.
+ *
+ * Returns 0 on success, negative value otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
+ */
+static int tomoyo_update_aggregator_entry(const char *original_name,
+ const char *aggregated_name,
+ const bool is_delete)
+{
+ struct tomoyo_aggregator_entry *ptr;
+ struct tomoyo_aggregator_entry e = { };
+ int error = is_delete ? -ENOENT : -ENOMEM;
+
+ if (!tomoyo_is_correct_path(original_name) ||
+ !tomoyo_is_correct_path(aggregated_name))
+ return -EINVAL;
+ e.original_name = tomoyo_get_name(original_name);
+ e.aggregated_name = tomoyo_get_name(aggregated_name);
+ if (!e.original_name || !e.aggregated_name ||
+ e.aggregated_name->is_patterned) /* No patterns allowed. */
+ goto out;
+ if (mutex_lock_interruptible(&tomoyo_policy_lock))
+ goto out;
+ list_for_each_entry_rcu(ptr, &tomoyo_aggregator_list, list) {
+ if (!tomoyo_is_same_aggregator_entry(ptr, &e))
+ continue;
+ ptr->is_deleted = is_delete;
+ error = 0;
+ break;
+ }
+ if (!is_delete && error) {
+ struct tomoyo_aggregator_entry *entry =
+ tomoyo_commit_ok(&e, sizeof(e));
+ if (entry) {
+ list_add_tail_rcu(&entry->list,
+ &tomoyo_aggregator_list);
+ error = 0;
+ }
+ }
+ mutex_unlock(&tomoyo_policy_lock);
+ out:
+ tomoyo_put_name(e.original_name);
+ tomoyo_put_name(e.aggregated_name);
+ return error;
+}
+
+/**
+ * tomoyo_read_aggregator_policy - Read "struct tomoyo_aggregator_entry" list.
+ *
+ * @head: Pointer to "struct tomoyo_io_buffer".
+ *
+ * Returns true on success, false otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
+ */
+bool tomoyo_read_aggregator_policy(struct tomoyo_io_buffer *head)
+{
+ struct list_head *pos;
+ bool done = true;
+
+ list_for_each_cookie(pos, head->read_var2, &tomoyo_aggregator_list) {
+ struct tomoyo_aggregator_entry *ptr;
+
+ ptr = list_entry(pos, struct tomoyo_aggregator_entry, list);
+ if (ptr->is_deleted)
+ continue;
+ done = tomoyo_io_printf(head, TOMOYO_KEYWORD_AGGREGATOR
+ "%s %s\n", ptr->original_name->name,
+ ptr->aggregated_name->name);
+ if (!done)
+ break;
+ }
+ return done;
+}
+
+/**
+ * tomoyo_write_aggregator_policy - Write "struct tomoyo_aggregator_entry" list.
+ *
+ * @data: String to parse.
+ * @is_delete: True if it is a delete request.
+ *
+ * Returns 0 on success, negative value otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
+ */
+int tomoyo_write_aggregator_policy(char *data, const bool is_delete)
+{
+ char *cp = strchr(data, ' ');
+
+ if (!cp)
+ return -EINVAL;
+ *cp++ = '\0';
+ return tomoyo_update_aggregator_entry(data, cp, is_delete);
+}
+
+/*
* tomoyo_alias_list is used for holding list of symlink's pathnames which are
* allowed to be passed to an execve() request. Normally, the domainname which
* the current process will belong to after execve() succeeds is calculated
@@ -732,6 +862,23 @@
}
}
+ /* Check 'aggregator' directive. */
+ {
+ struct tomoyo_aggregator_entry *ptr;
+ list_for_each_entry_rcu(ptr, &tomoyo_aggregator_list, list) {
+ if (ptr->is_deleted ||
+ !tomoyo_path_matches_pattern(&rn,
+ ptr->original_name))
+ continue;
+ if (need_kfree)
+ kfree(rn.name);
+ need_kfree = false;
+ /* This is OK because it is read only. */
+ rn = *ptr->aggregated_name;
+ break;
+ }
+ }
+
/* Check execute permission. */
retval = tomoyo_check_exec_perm(old_domain, &rn);
if (retval == TOMOYO_RETRY_REQUEST)
diff --git a/security/tomoyo/gc.c b/security/tomoyo/gc.c
index be2d3b9..8a31f0c 100644
--- a/security/tomoyo/gc.c
+++ b/security/tomoyo/gc.c
@@ -18,6 +18,7 @@
TOMOYO_ID_NUMBER_GROUP_MEMBER,
TOMOYO_ID_DOMAIN_INITIALIZER,
TOMOYO_ID_DOMAIN_KEEPER,
+ TOMOYO_ID_AGGREGATOR,
TOMOYO_ID_ALIAS,
TOMOYO_ID_GLOBALLY_READABLE,
TOMOYO_ID_PATTERN,
@@ -77,6 +78,12 @@
tomoyo_put_name(ptr->program);
}
+static void tomoyo_del_aggregator(struct tomoyo_aggregator_entry *ptr)
+{
+ tomoyo_put_name(ptr->original_name);
+ tomoyo_put_name(ptr->aggregated_name);
+}
+
static void tomoyo_del_alias(struct tomoyo_alias_entry *ptr)
{
tomoyo_put_name(ptr->original_name);
@@ -264,6 +271,17 @@
}
}
{
+ struct tomoyo_aggregator_entry *ptr;
+ list_for_each_entry_rcu(ptr, &tomoyo_aggregator_list, list) {
+ if (!ptr->is_deleted)
+ continue;
+ if (tomoyo_add_to_gc(TOMOYO_ID_AGGREGATOR, ptr))
+ list_del_rcu(&ptr->list);
+ else
+ break;
+ }
+ }
+ {
struct tomoyo_alias_entry *ptr;
list_for_each_entry_rcu(ptr, &tomoyo_alias_list, list) {
if (!ptr->is_deleted)
@@ -417,6 +435,9 @@
case TOMOYO_ID_DOMAIN_KEEPER:
tomoyo_del_domain_keeper(p->element);
break;
+ case TOMOYO_ID_AGGREGATOR:
+ tomoyo_del_aggregator(p->element);
+ break;
case TOMOYO_ID_ALIAS:
tomoyo_del_alias(p->element);
break;