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 <crypto/hash_info.h>
 19
 20enum pkey_algo {
 21	PKEY_ALGO_DSA,
 22	PKEY_ALGO_RSA,
 23	PKEY_ALGO__LAST
 24};
 25
 26extern const char *const pkey_algo_name[PKEY_ALGO__LAST];
 27extern const struct public_key_algorithm *pkey_algo[PKEY_ALGO__LAST];
 28
 29/* asymmetric key implementation supports only up to SHA224 */
 30#define PKEY_HASH__LAST		(HASH_ALGO_SHA224 + 1)
 31
 32enum pkey_id_type {
 33	PKEY_ID_PGP,		/* OpenPGP generated key ID */
 34	PKEY_ID_X509,		/* X.509 arbitrary subjectKeyIdentifier */
 35	PKEY_ID_TYPE__LAST
 36};
 37
 38extern const char *const pkey_id_type_name[PKEY_ID_TYPE__LAST];
 39
 40/*
 41 * Cryptographic data for the public-key subtype of the asymmetric key type.
 42 *
 43 * Note that this may include private part of the key as well as the public
 44 * part.
 45 */
 46struct public_key {
 47	const struct public_key_algorithm *algo;
 48	u8	capabilities;
 49#define PKEY_CAN_ENCRYPT	0x01
 50#define PKEY_CAN_DECRYPT	0x02
 51#define PKEY_CAN_SIGN		0x04
 52#define PKEY_CAN_VERIFY		0x08
 53	enum pkey_algo pkey_algo : 8;
 54	enum pkey_id_type id_type : 8;
 55	union {
 56		MPI	mpi[5];
 57		struct {
 58			MPI	p;	/* DSA prime */
 59			MPI	q;	/* DSA group order */
 60			MPI	g;	/* DSA group generator */
 61			MPI	y;	/* DSA public-key value = g^x mod p */
 62			MPI	x;	/* DSA secret exponent (if present) */
 63		} dsa;
 64		struct {
 65			MPI	n;	/* RSA public modulus */
 66			MPI	e;	/* RSA public encryption exponent */
 67			MPI	d;	/* RSA secret encryption exponent (if present) */
 68			MPI	p;	/* RSA secret prime (if present) */
 69			MPI	q;	/* RSA secret prime (if present) */
 70		} rsa;
 71	};
 72};
 73
 74extern void public_key_destroy(void *payload);
 75
 76/*
 77 * Public key cryptography signature data
 78 */
 79struct public_key_signature {
 80	u8 *digest;
 81	u8 digest_size;			/* Number of bytes in digest */
 82	u8 nr_mpi;			/* Occupancy of mpi[] */
 83	enum pkey_algo pkey_algo : 8;
 84	enum hash_algo pkey_hash_algo : 8;
 85	union {
 86		MPI mpi[2];
 87		struct {
 88			MPI s;		/* m^d mod n */
 89		} rsa;
 90		struct {
 91			MPI r;
 92			MPI s;
 93		} dsa;
 94	};
 95};
 96
 97struct key;
 98extern int verify_signature(const struct key *key,
 99			    const struct public_key_signature *sig);
100
101#endif /* _LINUX_PUBLIC_KEY_H */