1 files changed, 125 insertions, 0 deletions
diff --git a/include/linux/key-type.h b/include/linux/key-type.h
new file mode 100644
index 00000000..39e3c082
--- /dev/null
+++ b/include/linux/key-type.h
@@ -0,0 +1,125 @@
+/* Definitions for key type implementations
+ *
+ * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#ifndef _LINUX_KEY_TYPE_H
+#define _LINUX_KEY_TYPE_H
+
+#include <linux/key.h>
+
+#ifdef CONFIG_KEYS
+
+/*
+ * key under-construction record
+ * - passed to the request_key actor if supplied
+ */
+struct key_construction {
+	struct key	*key;	/* key being constructed */
+	struct key	*authkey;/* authorisation for key being constructed */
+};
+
+typedef int (*request_key_actor_t)(struct key_construction *key,
+				   const char *op, void *aux);
+
+/*
+ * kernel managed key type definition
+ */
+struct key_type {
+	/* name of the type */
+	const char *name;
+
+	/* default payload length for quota precalculation (optional)
+	 * - this can be used instead of calling key_payload_reserve(), that
+	 *   function only needs to be called if the real datalen is different
+	 */
+	size_t def_datalen;
+
+	/* vet a description */
+	int (*vet_description)(const char *description);
+
+	/* instantiate a key of this type
+	 * - this method should call key_payload_reserve() to determine if the
+	 *   user's quota will hold the payload
+	 */
+	int (*instantiate)(struct key *key, const void *data, size_t datalen);
+
+	/* update a key of this type (optional)
+	 * - this method should call key_payload_reserve() to recalculate the
+	 *   quota consumption
+	 * - the key must be locked against read when modifying
+	 */
+	int (*update)(struct key *key, const void *data, size_t datalen);
+
+	/* match a key against a description */
+	int (*match)(const struct key *key, const void *desc);
+
+	/* clear some of the data from a key on revokation (optional)
+	 * - the key's semaphore will be write-locked by the caller
+	 */
+	void (*revoke)(struct key *key);
+
+	/* clear the data from a key (optional) */
+	void (*destroy)(struct key *key);
+
+	/* describe a key */
+	void (*describe)(const struct key *key, struct seq_file *p);
+
+	/* read a key's data (optional)
+	 * - permission checks will be done by the caller
+	 * - the key's semaphore will be readlocked by the caller
+	 * - should return the amount of data that could be read, no matter how
+	 *   much is copied into the buffer
+	 * - shouldn't do the copy if the buffer is NULL
+	 */
+	long (*read)(const struct key *key, char __user *buffer, size_t buflen);
+
+	/* handle request_key() for this type instead of invoking
+	 * /sbin/request-key (optional)
+	 * - key is the key to instantiate
+	 * - authkey is the authority to assume when instantiating this key
+	 * - op is the operation to be done, usually "create"
+	 * - the call must not return until the instantiation process has run
+	 *   its course
+	 */
+	request_key_actor_t request_key;
+
+	/* internal fields */
+	struct list_head	link;		/* link in types list */
+	struct lock_class_key	lock_class;	/* key->sem lock class */
+};
+
+extern struct key_type key_type_keyring;
+
+extern int register_key_type(struct key_type *ktype);
+extern void unregister_key_type(struct key_type *ktype);
+
+extern int key_payload_reserve(struct key *key, size_t datalen);
+extern int key_instantiate_and_link(struct key *key,
+				    const void *data,
+				    size_t datalen,
+				    struct key *keyring,
+				    struct key *instkey);
+extern int key_reject_and_link(struct key *key,
+			       unsigned timeout,
+			       unsigned error,
+			       struct key *keyring,
+			       struct key *instkey);
+extern void complete_request_key(struct key_construction *cons, int error);
+
+static inline int key_negate_and_link(struct key *key,
+				      unsigned timeout,
+				      struct key *keyring,
+				      struct key *instkey)
+{
+	return key_reject_and_link(key, timeout, ENOKEY, keyring, instkey);
+}
+
+#endif /* CONFIG_KEYS */
+#endif /* _LINUX_KEY_TYPE_H */