diff --git a/security/tomoyo/group.c b/security/tomoyo/group.c
new file mode 100644
index 0000000..3f0a2ab
--- /dev/null
+++ b/security/tomoyo/group.c
@@ -0,0 +1,130 @@
+/*
+ * security/tomoyo/group.c
+ *
+ * Copyright (C) 2005-2010  NTT DATA CORPORATION
+ */
+
+#include <linux/slab.h>
+#include "common.h"
+
+static bool tomoyo_same_path_group(const struct tomoyo_acl_head *a,
+				const struct tomoyo_acl_head *b)
+{
+	return container_of(a, struct tomoyo_path_group, head)->member_name ==
+		container_of(b, struct tomoyo_path_group, head)->member_name;
+}
+
+static bool tomoyo_same_number_group(const struct tomoyo_acl_head *a,
+				  const struct tomoyo_acl_head *b)
+{
+	return !memcmp(&container_of(a, struct tomoyo_number_group, head)
+		       ->number,
+		       &container_of(b, struct tomoyo_number_group, head)
+		       ->number,
+		       sizeof(container_of(a, struct tomoyo_number_group, head)
+			      ->number));
+}
+
+/**
+ * tomoyo_write_group - Write "struct tomoyo_path_group"/"struct tomoyo_number_group" list.
+ *
+ * @data:      String to parse.
+ * @is_delete: True if it is a delete request.
+ * @type:      Type of this group.
+ *
+ * Returns 0 on success, negative value otherwise.
+ */
+int tomoyo_write_group(char *data, const bool is_delete, const u8 type)
+{
+	struct tomoyo_group *group;
+	struct list_head *member;
+	char *w[2];
+	int error = -EINVAL;
+	if (!tomoyo_tokenize(data, w, sizeof(w)) || !w[1][0])
+		return -EINVAL;
+	group = tomoyo_get_group(w[0], type);
+	if (!group)
+		return -ENOMEM;
+	member = &group->member_list;
+	if (type == TOMOYO_PATH_GROUP) {
+		struct tomoyo_path_group e = { };
+		e.member_name = tomoyo_get_name(w[1]);
+		if (!e.member_name) {
+			error = -ENOMEM;
+			goto out;
+		}
+		error = tomoyo_update_policy(&e.head, sizeof(e), is_delete,
+					     member, tomoyo_same_path_group);
+		tomoyo_put_name(e.member_name);
+	} else if (type == TOMOYO_NUMBER_GROUP) {
+		struct tomoyo_number_group e = { };
+		if (w[1][0] == '@'
+		    || !tomoyo_parse_number_union(w[1], &e.number)
+		    || e.number.values[0] > e.number.values[1])
+			goto out;
+		error = tomoyo_update_policy(&e.head, sizeof(e), is_delete,
+					     member, tomoyo_same_number_group);
+		/*
+		 * tomoyo_put_number_union() is not needed because
+		 * w[1][0] != '@'.
+		 */
+	}
+ out:
+	tomoyo_put_group(group);
+	return error;
+}
+
+/**
+ * tomoyo_path_matches_group - Check whether the given pathname matches members of the given pathname group.
+ *
+ * @pathname:        The name of pathname.
+ * @group:           Pointer to "struct tomoyo_path_group".
+ *
+ * Returns true if @pathname matches pathnames in @group, false otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
+ */
+bool tomoyo_path_matches_group(const struct tomoyo_path_info *pathname,
+			       const struct tomoyo_group *group)
+{
+	struct tomoyo_path_group *member;
+	bool matched = false;
+	list_for_each_entry_rcu(member, &group->member_list, head.list) {
+		if (member->head.is_deleted)
+			continue;
+		if (!tomoyo_path_matches_pattern(pathname, member->member_name))
+			continue;
+		matched = true;
+		break;
+	}
+	return matched;
+}
+
+/**
+ * tomoyo_number_matches_group - Check whether the given number matches members of the given number group.
+ *
+ * @min:   Min number.
+ * @max:   Max number.
+ * @group: Pointer to "struct tomoyo_number_group".
+ *
+ * Returns true if @min and @max partially overlaps @group, false otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
+ */
+bool tomoyo_number_matches_group(const unsigned long min,
+				 const unsigned long max,
+				 const struct tomoyo_group *group)
+{
+	struct tomoyo_number_group *member;
+	bool matched = false;
+	list_for_each_entry_rcu(member, &group->member_list, head.list) {
+		if (member->head.is_deleted)
+			continue;
+		if (min > member->number.values[1] ||
+		    max < member->number.values[0])
+			continue;
+		matched = true;
+		break;
+	}
+	return matched;
+}