linux/security
David Howells d4f65b5d24 KEYS: Add payload preparsing opportunity prior to key instantiate or update
Give the key type the opportunity to preparse the payload prior to the
instantiation and update routines being called.  This is done with the
provision of two new key type operations:

	int (*preparse)(struct key_preparsed_payload *prep);
	void (*free_preparse)(struct key_preparsed_payload *prep);

If the first operation is present, then it is called before key creation (in
the add/update case) or before the key semaphore is taken (in the update and
instantiate cases).  The second operation is called to clean up if the first
was called.

preparse() is given the opportunity to fill in the following structure:

	struct key_preparsed_payload {
		char		*description;
		void		*type_data[2];
		void		*payload;
		const void	*data;
		size_t		datalen;
		size_t		quotalen;
	};

Before the preparser is called, the first three fields will have been cleared,
the payload pointer and size will be stored in data and datalen and the default
quota size from the key_type struct will be stored into quotalen.

The preparser may parse the payload in any way it likes and may store data in
the type_data[] and payload fields for use by the instantiate() and update()
ops.

The preparser may also propose a description for the key by attaching it as a
string to the description field.  This can be used by passing a NULL or ""
description to the add_key() system call or the key_create_or_update()
function.  This cannot work with request_key() as that required the description
to tell the upcall about the key to be created.

This, for example permits keys that store PGP public keys to generate their own
name from the user ID and public key fingerprint in the key.

The instantiate() and update() operations are then modified to look like this:

	int (*instantiate)(struct key *key, struct key_preparsed_payload *prep);
	int (*update)(struct key *key, struct key_preparsed_payload *prep);

and the new payload data is passed in *prep, whether or not it was preparsed.

Signed-off-by: David Howells <dhowells@redhat.com>
2012-09-13 13:06:29 +01:00
..
apparmor split ->file_mmap() into ->mmap_addr()/->mmap_file() 2012-05-31 13:11:54 -04:00
integrity ima: audit is compiled only when enabled 2012-07-05 16:43:59 -04:00
keys KEYS: Add payload preparsing opportunity prior to key instantiate or update 2012-09-13 13:06:29 +01:00
selinux selinux: tag avc cache alloc as non-critical 2012-07-31 18:42:47 -07:00
smack smack: off by one error 2012-07-30 15:04:17 +10:00
tomoyo Merge branch 'master' of git://git.infradead.org/users/eparis/selinux into next 2012-05-22 11:21:06 +10:00
yama Yama: access task_struct->comm directly 2012-08-17 20:40:38 +10:00
capability.c split ->file_mmap() into ->mmap_addr()/->mmap_file() 2012-05-31 13:11:54 -04:00
commoncap.c split ->file_mmap() into ->mmap_addr()/->mmap_file() 2012-05-31 13:11:54 -04:00
device_cgroup.c cgroup: convert all non-memcg controllers to the new cftype interface 2012-04-01 12:09:55 -07:00
inode.c securityfs: fix object creation races 2012-01-10 10:20:35 -05:00
Kconfig KEYS: Move the key config into security/keys/Kconfig 2012-05-11 10:56:56 +01:00
lsm_audit.c LSM: BUILD_BUG_ON if the common_audit_data union ever grows 2012-04-09 12:23:03 -04:00
Makefile security: Yama LSM 2012-02-10 09:18:52 +11:00
min_addr.c mmap_min_addr check CAP_SYS_RAWIO only for write 2010-04-23 08:56:31 +10:00
security.c security: Fix nommu build. 2012-07-03 21:41:03 +10:00