linux/include/keys/asymmetric-type.h
Mauro Carvalho Chehab 0efaaa8658 docs: crypto: convert asymmetric-keys.txt to ReST
This file is almost compatible with ReST. Just minor changes
were needed:

- Adjust document and titles markups;
- Adjust numbered list markups;
- Add a comments markup for the Contents section;
- Add markups for literal blocks.

Acked-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/c2275ea94e0507a01b020ab66dfa824d8b1c2545.1592203650.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-06-19 14:03:46 -06:00

85 lines
2.7 KiB
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
/* Asymmetric Public-key cryptography key type interface
*
* See Documentation/crypto/asymmetric-keys.rst
*
* Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*/
#ifndef _KEYS_ASYMMETRIC_TYPE_H
#define _KEYS_ASYMMETRIC_TYPE_H
#include <linux/key-type.h>
#include <linux/verification.h>
extern struct key_type key_type_asymmetric;
/*
* The key payload is four words. The asymmetric-type key uses them as
* follows:
*/
enum asymmetric_payload_bits {
asym_crypto, /* The data representing the key */
asym_subtype, /* Pointer to an asymmetric_key_subtype struct */
asym_key_ids, /* Pointer to an asymmetric_key_ids struct */
asym_auth /* The key's authorisation (signature, parent key ID) */
};
/*
* Identifiers for an asymmetric key ID. We have three ways of looking up a
* key derived from an X.509 certificate:
*
* (1) Serial Number & Issuer. Non-optional. This is the only valid way to
* map a PKCS#7 signature to an X.509 certificate.
*
* (2) Issuer & Subject Unique IDs. Optional. These were the original way to
* match X.509 certificates, but have fallen into disuse in favour of (3).
*
* (3) Auth & Subject Key Identifiers. Optional. SKIDs are only provided on
* CA keys that are intended to sign other keys, so don't appear in end
* user certificates unless forced.
*
* We could also support an PGP key identifier, which is just a SHA1 sum of the
* public key and certain parameters, but since we don't support PGP keys at
* the moment, we shall ignore those.
*
* What we actually do is provide a place where binary identifiers can be
* stashed and then compare against them when checking for an id match.
*/
struct asymmetric_key_id {
unsigned short len;
unsigned char data[];
};
struct asymmetric_key_ids {
void *id[2];
};
extern bool asymmetric_key_id_same(const struct asymmetric_key_id *kid1,
const struct asymmetric_key_id *kid2);
extern bool asymmetric_key_id_partial(const struct asymmetric_key_id *kid1,
const struct asymmetric_key_id *kid2);
extern struct asymmetric_key_id *asymmetric_key_generate_id(const void *val_1,
size_t len_1,
const void *val_2,
size_t len_2);
static inline
const struct asymmetric_key_ids *asymmetric_key_ids(const struct key *key)
{
return key->payload.data[asym_key_ids];
}
extern struct key *find_asymmetric_key(struct key *keyring,
const struct asymmetric_key_id *id_0,
const struct asymmetric_key_id *id_1,
bool partial);
/*
* The payload is at the discretion of the subtype.
*/
#endif /* _KEYS_ASYMMETRIC_TYPE_H */