linux/include/crypto/public_key.h

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/* Asymmetric public-key algorithm definitions
*
* See Documentation/crypto/asymmetric-keys.txt
*
* Copyright (C) 2012 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_PUBLIC_KEY_H
#define _LINUX_PUBLIC_KEY_H
#include <linux/mpi.h>
KEYS: Overhaul key identification when searching for asymmetric keys Make use of the new match string preparsing to overhaul key identification when searching for asymmetric keys. The following changes are made: (1) Use the previously created asymmetric_key_id struct to hold the following key IDs derived from the X.509 certificate or PKCS#7 message: id: serial number + issuer skid: subjKeyId + subject authority: authKeyId + issuer (2) Replace the hex fingerprint attached to key->type_data[1] with an asymmetric_key_ids struct containing the id and the skid (if present). (3) Make the asymmetric_type match data preparse select one of two searches: (a) An iterative search for the key ID given if prefixed with "id:". The prefix is expected to be followed by a hex string giving the ID to search for. The criterion key ID is checked against all key IDs recorded on the key. (b) A direct search if the key ID is not prefixed with "id:". This will look for an exact match on the key description. (4) Make x509_request_asymmetric_key() take a key ID. This is then converted into "id:<hex>" and passed into keyring_search() where match preparsing will turn it back into a binary ID. (5) X.509 certificate verification then takes the authority key ID and looks up a key that matches it to find the public key for the certificate signature. (6) PKCS#7 certificate verification then takes the id key ID and looks up a key that matches it to find the public key for the signed information block signature. Additional changes: (1) Multiple subjKeyId and authKeyId values on an X.509 certificate cause the cert to be rejected with -EBADMSG. (2) The 'fingerprint' ID is gone. This was primarily intended to convey PGP public key fingerprints. If PGP is supported in future, this should generate a key ID that carries the fingerprint. (3) Th ca_keyid= kernel command line option is now converted to a key ID and used to match the authority key ID. Possibly this should only match the actual authKeyId part and not the issuer as well. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Vivek Goyal <vgoyal@redhat.com>
2014-09-17 00:36:13 +08:00
#include <keys/asymmetric-type.h>
#include <crypto/hash_info.h>
enum pkey_algo {
PKEY_ALGO_DSA,
PKEY_ALGO_RSA,
PKEY_ALGO__LAST
};
extern const char *const pkey_algo_name[PKEY_ALGO__LAST];
extern const struct public_key_algorithm *pkey_algo[PKEY_ALGO__LAST];
/* asymmetric key implementation supports only up to SHA224 */
#define PKEY_HASH__LAST (HASH_ALGO_SHA224 + 1)
enum pkey_id_type {
PKEY_ID_PGP, /* OpenPGP generated key ID */
PKEY_ID_X509, /* X.509 arbitrary subjectKeyIdentifier */
PKEY_ID_TYPE__LAST
};
extern const char *const pkey_id_type_name[PKEY_ID_TYPE__LAST];
/*
* Cryptographic data for the public-key subtype of the asymmetric key type.
*
* Note that this may include private part of the key as well as the public
* part.
*/
struct public_key {
const struct public_key_algorithm *algo;
u8 capabilities;
#define PKEY_CAN_ENCRYPT 0x01
#define PKEY_CAN_DECRYPT 0x02
#define PKEY_CAN_SIGN 0x04
#define PKEY_CAN_VERIFY 0x08
enum pkey_algo pkey_algo : 8;
enum pkey_id_type id_type : 8;
union {
MPI mpi[5];
struct {
MPI p; /* DSA prime */
MPI q; /* DSA group order */
MPI g; /* DSA group generator */
MPI y; /* DSA public-key value = g^x mod p */
MPI x; /* DSA secret exponent (if present) */
} dsa;
struct {
MPI n; /* RSA public modulus */
MPI e; /* RSA public encryption exponent */
MPI d; /* RSA secret encryption exponent (if present) */
MPI p; /* RSA secret prime (if present) */
MPI q; /* RSA secret prime (if present) */
} rsa;
};
};
extern void public_key_destroy(void *payload);
/*
* Public key cryptography signature data
*/
struct public_key_signature {
u8 *digest;
u8 digest_size; /* Number of bytes in digest */
u8 nr_mpi; /* Occupancy of mpi[] */
enum pkey_algo pkey_algo : 8;
enum hash_algo pkey_hash_algo : 8;
union {
MPI mpi[2];
struct {
MPI s; /* m^d mod n */
} rsa;
struct {
MPI r;
MPI s;
} dsa;
};
};
struct key;
extern int verify_signature(const struct key *key,
const struct public_key_signature *sig);
KEYS: Overhaul key identification when searching for asymmetric keys Make use of the new match string preparsing to overhaul key identification when searching for asymmetric keys. The following changes are made: (1) Use the previously created asymmetric_key_id struct to hold the following key IDs derived from the X.509 certificate or PKCS#7 message: id: serial number + issuer skid: subjKeyId + subject authority: authKeyId + issuer (2) Replace the hex fingerprint attached to key->type_data[1] with an asymmetric_key_ids struct containing the id and the skid (if present). (3) Make the asymmetric_type match data preparse select one of two searches: (a) An iterative search for the key ID given if prefixed with "id:". The prefix is expected to be followed by a hex string giving the ID to search for. The criterion key ID is checked against all key IDs recorded on the key. (b) A direct search if the key ID is not prefixed with "id:". This will look for an exact match on the key description. (4) Make x509_request_asymmetric_key() take a key ID. This is then converted into "id:<hex>" and passed into keyring_search() where match preparsing will turn it back into a binary ID. (5) X.509 certificate verification then takes the authority key ID and looks up a key that matches it to find the public key for the certificate signature. (6) PKCS#7 certificate verification then takes the id key ID and looks up a key that matches it to find the public key for the signed information block signature. Additional changes: (1) Multiple subjKeyId and authKeyId values on an X.509 certificate cause the cert to be rejected with -EBADMSG. (2) The 'fingerprint' ID is gone. This was primarily intended to convey PGP public key fingerprints. If PGP is supported in future, this should generate a key ID that carries the fingerprint. (3) Th ca_keyid= kernel command line option is now converted to a key ID and used to match the authority key ID. Possibly this should only match the actual authKeyId part and not the issuer as well. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Vivek Goyal <vgoyal@redhat.com>
2014-09-17 00:36:13 +08:00
struct asymmetric_key_id;
extern struct key *x509_request_asymmetric_key(struct key *keyring,
const struct asymmetric_key_id *id,
const struct asymmetric_key_id *skid,
bool partial);
#endif /* _LINUX_PUBLIC_KEY_H */