1/* Asymmetric public-key algorithm definitions
2 *
3 * See Documentation/crypto/asymmetric-keys.txt
4 *
5 * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
6 * Written by David Howells (dhowells@redhat.com)
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public Licence
10 * as published by the Free Software Foundation; either version
11 * 2 of the Licence, or (at your option) any later version.
12 */
13
14#ifndef _LINUX_PUBLIC_KEY_H
15#define _LINUX_PUBLIC_KEY_H
16
17#include <linux/mpi.h>
18#include <keys/asymmetric-type.h>
19#include <crypto/hash_info.h>
20
21enum pkey_algo {
22	PKEY_ALGO_DSA,
23	PKEY_ALGO_RSA,
24	PKEY_ALGO__LAST
25};
26
27extern const char *const pkey_algo_name[PKEY_ALGO__LAST];
28extern const struct public_key_algorithm *pkey_algo[PKEY_ALGO__LAST];
29
30/* asymmetric key implementation supports only up to SHA224 */
31#define PKEY_HASH__LAST		(HASH_ALGO_SHA224 + 1)
32
33enum pkey_id_type {
34	PKEY_ID_PGP,		/* OpenPGP generated key ID */
35	PKEY_ID_X509,		/* X.509 arbitrary subjectKeyIdentifier */
36	PKEY_ID_TYPE__LAST
37};
38
39extern const char *const pkey_id_type_name[PKEY_ID_TYPE__LAST];
40
41/*
42 * Cryptographic data for the public-key subtype of the asymmetric key type.
43 *
44 * Note that this may include private part of the key as well as the public
45 * part.
46 */
47struct public_key {
48	const struct public_key_algorithm *algo;
49	u8	capabilities;
50#define PKEY_CAN_ENCRYPT	0x01
51#define PKEY_CAN_DECRYPT	0x02
52#define PKEY_CAN_SIGN		0x04
53#define PKEY_CAN_VERIFY		0x08
54	enum pkey_algo pkey_algo : 8;
55	enum pkey_id_type id_type : 8;
56	union {
57		MPI	mpi[5];
58		struct {
59			MPI	p;	/* DSA prime */
60			MPI	q;	/* DSA group order */
61			MPI	g;	/* DSA group generator */
62			MPI	y;	/* DSA public-key value = g^x mod p */
63			MPI	x;	/* DSA secret exponent (if present) */
64		} dsa;
65		struct {
66			MPI	n;	/* RSA public modulus */
67			MPI	e;	/* RSA public encryption exponent */
68			MPI	d;	/* RSA secret encryption exponent (if present) */
69			MPI	p;	/* RSA secret prime (if present) */
70			MPI	q;	/* RSA secret prime (if present) */
71		} rsa;
72	};
73};
74
75extern void public_key_destroy(void *payload);
76
77/*
78 * Public key cryptography signature data
79 */
80struct public_key_signature {
81	u8 *digest;
82	u8 digest_size;			/* Number of bytes in digest */
83	u8 nr_mpi;			/* Occupancy of mpi[] */
84	enum pkey_algo pkey_algo : 8;
85	enum hash_algo pkey_hash_algo : 8;
86	union {
87		MPI mpi[2];
88		struct {
89			MPI s;		/* m^d mod n */
90		} rsa;
91		struct {
92			MPI r;
93			MPI s;
94		} dsa;
95	};
96};
97
98struct key;
99extern int verify_signature(const struct key *key,
100			    const struct public_key_signature *sig);
101
102struct asymmetric_key_id;
103extern struct key *x509_request_asymmetric_key(struct key *keyring,
104					       const struct asymmetric_key_id *kid,
105					       bool partial);
106
107#endif /* _LINUX_PUBLIC_KEY_H */
108