/*

 * Copyright (c) 2002 Bob Beck <beck@openbsd.org>

 * Copyright (c) 2002 Theo de Raadt

 * Copyright (c) 2002 Markus Friedl

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY

 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE

 * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY

 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES

 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;

 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND

 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF

 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 *

 */

#include <openssl/objects.h>

#include <openssl/engine.h>

#include <openssl/evp.h>

#include <openssl/bn.h>

#if (defined(__unix__) || defined(unix)) && !defined(USG) && \

	(defined(OpenBSD) || defined(__FreeBSD_version))

#include <sys/param.h>

# if (OpenBSD >= 200112) || ((__FreeBSD_version >= 470101 && __FreeBSD_version < 500000) || __FreeBSD_version >= 500041)

#  define HAVE_CRYPTODEV

# endif

# if (OpenBSD >= 200110)

#  define HAVE_SYSLOG_R

# endif

#endif

#ifndef HAVE_CRYPTODEV

EXPORT_C void

ENGINE_load_cryptodev(void)

{

	/* This is a NOP on platforms without /dev/crypto */

	return;

}

#else 

#include <sys/types.h>

#include <crypto/cryptodev.h>

#include <sys/ioctl.h>

#include <errno.h>

#include <stdio.h>

#include <unistd.h>

#include <fcntl.h>

#include <stdarg.h>

#include <syslog.h>

#include <errno.h>

#include <string.h>

struct dev_crypto_state {

	struct session_op d_sess;

	int d_fd;

};

static u_int32_t cryptodev_asymfeat = 0;

static int get_asym_dev_crypto(void);

static int open_dev_crypto(void);

static int get_dev_crypto(void);

static int cryptodev_max_iv(int cipher);

static int cryptodev_key_length_valid(int cipher, int len);

static int cipher_nid_to_cryptodev(int nid);

static int get_cryptodev_ciphers(const int **cnids);

static int get_cryptodev_digests(const int **cnids);

static int cryptodev_usable_ciphers(const int **nids);

static int cryptodev_usable_digests(const int **nids);

static int cryptodev_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,

    const unsigned char *in, unsigned int inl);

static int cryptodev_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,

    const unsigned char *iv, int enc);

static int cryptodev_cleanup(EVP_CIPHER_CTX *ctx);

static int cryptodev_engine_ciphers(ENGINE *e, const EVP_CIPHER **cipher,

    const int **nids, int nid);

static int cryptodev_engine_digests(ENGINE *e, const EVP_MD **digest,

    const int **nids, int nid);

static int bn2crparam(const BIGNUM *a, struct crparam *crp);

static int crparam2bn(struct crparam *crp, BIGNUM *a);

static void zapparams(struct crypt_kop *kop);

static int cryptodev_asym(struct crypt_kop *kop, int rlen, BIGNUM *r,

    int slen, BIGNUM *s);

static int cryptodev_bn_mod_exp(BIGNUM *r, const BIGNUM *a,

    const BIGNUM *p, const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *m_ctx);

static int cryptodev_rsa_nocrt_mod_exp(BIGNUM *r0, const BIGNUM *I,

    RSA *rsa);

static int cryptodev_rsa_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx);

static int cryptodev_dsa_bn_mod_exp(DSA *dsa, BIGNUM *r, BIGNUM *a,

    const BIGNUM *p, const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *m_ctx);

static int cryptodev_dsa_dsa_mod_exp(DSA *dsa, BIGNUM *t1, BIGNUM *g,

    BIGNUM *u1, BIGNUM *pub_key, BIGNUM *u2, BIGNUM *p,

    BN_CTX *ctx, BN_MONT_CTX *mont);

static DSA_SIG *cryptodev_dsa_do_sign(const unsigned char *dgst,

    int dlen, DSA *dsa);

static int cryptodev_dsa_verify(const unsigned char *dgst, int dgst_len,

    DSA_SIG *sig, DSA *dsa);

static int cryptodev_mod_exp_dh(const DH *dh, BIGNUM *r, const BIGNUM *a,

    const BIGNUM *p, const BIGNUM *m, BN_CTX *ctx,

    BN_MONT_CTX *m_ctx);

static int cryptodev_dh_compute_key(unsigned char *key,

    const BIGNUM *pub_key, DH *dh);

static int cryptodev_ctrl(ENGINE *e, int cmd, long i, void *p,

    void (*f)());

void ENGINE_load_cryptodev(void);

static const ENGINE_CMD_DEFN cryptodev_defns[] = {

	{ 0, NULL, NULL, 0 }

};

static struct {

	int	id;

	int	nid;

	int	ivmax;

	int	keylen;

} ciphers[] = {

	{ CRYPTO_DES_CBC,		NID_des_cbc,		8,	 8, },

	{ CRYPTO_3DES_CBC,		NID_des_ede3_cbc,	8,	24, },

	{ CRYPTO_AES_CBC,		NID_aes_128_cbc,	16,	16, },

	{ CRYPTO_BLF_CBC,		NID_bf_cbc,		8,	16, },

	{ CRYPTO_CAST_CBC,		NID_cast5_cbc,		8,	16, },

	{ CRYPTO_SKIPJACK_CBC,		NID_undef,		0,	 0, },

	{ 0,				NID_undef,		0,	 0, },

};

static struct {

	int	id;

	int	nid;

} digests[] = {

	{ CRYPTO_SHA1_HMAC,		NID_hmacWithSHA1,	},

	{ CRYPTO_RIPEMD160_HMAC,	NID_ripemd160,		},

	{ CRYPTO_MD5_KPDK,		NID_undef,		},

	{ CRYPTO_SHA1_KPDK,		NID_undef,		},

	{ CRYPTO_MD5,			NID_md5,		},

	{ CRYPTO_SHA1,			NID_undef,		},

	{ 0,				NID_undef,		},

};

/*

 * Return a fd if /dev/crypto seems usable, 0 otherwise.

 */

static int

open_dev_crypto(void)

{

	static int fd = -1;

	if (fd == -1) {

		if ((fd = open("/dev/crypto", O_RDWR, 0)) == -1)

			return (-1);

		/* close on exec */

		if (fcntl(fd, F_SETFD, 1) == -1) {

			close(fd);

			fd = -1;

			return (-1);

		}

	}

	return (fd);

}

static int

get_dev_crypto(void)

{

	int fd, retfd;

	if ((fd = open_dev_crypto()) == -1)

		return (-1);

	if (ioctl(fd, CRIOGET, &retfd) == -1)

		return (-1);

	/* close on exec */

	if (fcntl(retfd, F_SETFD, 1) == -1) {

		close(retfd);

		return (-1);

	}

	return (retfd);

}

/* Caching version for asym operations */

static int

get_asym_dev_crypto(void)

{

	static int fd = -1;

	if (fd == -1)

		fd = get_dev_crypto();

	return fd;

}

/*

 * XXXX this needs to be set for each alg - and determined from

 * a running card.

 */

static int

cryptodev_max_iv(int cipher)

{

	int i;

	for (i = 0; ciphers[i].id; i++)

		if (ciphers[i].id == cipher)

			return (ciphers[i].ivmax);

	return (0);

}

/*

 * XXXX this needs to be set for each alg - and determined from

 * a running card. For now, fake it out - but most of these

 * for real devices should return 1 for the supported key

 * sizes the device can handle.

 */

static int

cryptodev_key_length_valid(int cipher, int len)

{

	int i;

	for (i = 0; ciphers[i].id; i++)

		if (ciphers[i].id == cipher)

			return (ciphers[i].keylen == len);

	return (0);

}

/* convert libcrypto nids to cryptodev */

static int

cipher_nid_to_cryptodev(int nid)

{

	int i;

	for (i = 0; ciphers[i].id; i++)

		if (ciphers[i].nid == nid)

			return (ciphers[i].id);

	return (0);

}

/*

 * Find out what ciphers /dev/crypto will let us have a session for.

 * XXX note, that some of these openssl doesn't deal with yet!

 * returning them here is harmless, as long as we return NULL

 * when asked for a handler in the cryptodev_engine_ciphers routine

 */

static int

get_cryptodev_ciphers(const int **cnids)

{

	static int nids[CRYPTO_ALGORITHM_MAX];

	struct session_op sess;

	int fd, i, count = 0;

	if ((fd = get_dev_crypto()) < 0) {

		*cnids = NULL;

		return (0);

	}

	memset(&sess, 0, sizeof(sess));

	sess.key = (caddr_t)"123456781234567812345678";

	for (i = 0; ciphers[i].id && count < CRYPTO_ALGORITHM_MAX; i++) {

		if (ciphers[i].nid == NID_undef)

			continue;

		sess.cipher = ciphers[i].id;

		sess.keylen = ciphers[i].keylen;

		sess.mac = 0;

		if (ioctl(fd, CIOCGSESSION, &sess) != -1 &&

		    ioctl(fd, CIOCFSESSION, &sess.ses) != -1)

			nids[count++] = ciphers[i].nid;

	}

	close(fd);

	if (count > 0)

		*cnids = nids;

	else

		*cnids = NULL;

	return (count);

}

/*

 * Find out what digests /dev/crypto will let us have a session for.

 * XXX note, that some of these openssl doesn't deal with yet!

 * returning them here is harmless, as long as we return NULL

 * when asked for a handler in the cryptodev_engine_digests routine

 */

static int

get_cryptodev_digests(const int **cnids)

{

	static int nids[CRYPTO_ALGORITHM_MAX];

	struct session_op sess;

	int fd, i, count = 0;

	if ((fd = get_dev_crypto()) < 0) {

		*cnids = NULL;

		return (0);

	}

	memset(&sess, 0, sizeof(sess));

	for (i = 0; digests[i].id && count < CRYPTO_ALGORITHM_MAX; i++) {

		if (digests[i].nid == NID_undef)

			continue;

		sess.mac = digests[i].id;

		sess.cipher = 0;

		if (ioctl(fd, CIOCGSESSION, &sess) != -1 &&

		    ioctl(fd, CIOCFSESSION, &sess.ses) != -1)

			nids[count++] = digests[i].nid;

	}

	close(fd);

	if (count > 0)

		*cnids = nids;

	else

		*cnids = NULL;

	return (count);

}

/*

 * Find the useable ciphers|digests from dev/crypto - this is the first

 * thing called by the engine init crud which determines what it

 * can use for ciphers from this engine. We want to return

 * only what we can do, anythine else is handled by software.

 *

 * If we can't initialize the device to do anything useful for

 * any reason, we want to return a NULL array, and 0 length,

 * which forces everything to be done is software. By putting

 * the initalization of the device in here, we ensure we can

 * use this engine as the default, and if for whatever reason

 * /dev/crypto won't do what we want it will just be done in

 * software

 *

 * This can (should) be greatly expanded to perhaps take into

 * account speed of the device, and what we want to do.

 * (although the disabling of particular alg's could be controlled

 * by the device driver with sysctl's.) - this is where we

 * want most of the decisions made about what we actually want

 * to use from /dev/crypto.

 */

static int

cryptodev_usable_ciphers(const int **nids)

{

	return (get_cryptodev_ciphers(nids));

}

static int

cryptodev_usable_digests(const int **nids)

{

	/*

	 * XXXX just disable all digests for now, because it sucks.

	 * we need a better way to decide this - i.e. I may not

	 * want digests on slow cards like hifn on fast machines,

	 * but might want them on slow or loaded machines, etc.

	 * will also want them when using crypto cards that don't

	 * suck moose gonads - would be nice to be able to decide something

	 * as reasonable default without having hackery that's card dependent.

	 * of course, the default should probably be just do everything,

	 * with perhaps a sysctl to turn algoritms off (or have them off

	 * by default) on cards that generally suck like the hifn.

	 */

	*nids = NULL;

	return (0);

}

static int

cryptodev_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,

    const unsigned char *in, unsigned int inl)

{

	struct crypt_op cryp;

	struct dev_crypto_state *state = ctx->cipher_data;

	struct session_op *sess = &state->d_sess;

	void *iiv;

	unsigned char save_iv[EVP_MAX_IV_LENGTH];

	if (state->d_fd < 0)

		return (0);

	if (!inl)

		return (1);

	if ((inl % ctx->cipher->block_size) != 0)

		return (0);

	memset(&cryp, 0, sizeof(cryp));

	cryp.ses = sess->ses;

	cryp.flags = 0;

	cryp.len = inl;

	cryp.src = (caddr_t) in;

	cryp.dst = (caddr_t) out;

	cryp.mac = 0;

	cryp.op = ctx->encrypt ? COP_ENCRYPT : COP_DECRYPT;

	if (ctx->cipher->iv_len) {

		cryp.iv = (caddr_t) ctx->iv;

		if (!ctx->encrypt) {

			iiv = (void *) in + inl - ctx->cipher->iv_len;

			memcpy(save_iv, iiv, ctx->cipher->iv_len);

		}

	} else

		cryp.iv = NULL;

	if (ioctl(state->d_fd, CIOCCRYPT, &cryp) == -1) {

		/* XXX need better errror handling

		 * this can fail for a number of different reasons.

		 */

		return (0);

	}

	if (ctx->cipher->iv_len) {

		if (ctx->encrypt)

			iiv = (void *) out + inl - ctx->cipher->iv_len;

		else

			iiv = save_iv;

		memcpy(ctx->iv, iiv, ctx->cipher->iv_len);

	}

	return (1);

}

static int

cryptodev_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,

    const unsigned char *iv, int enc)

{

	struct dev_crypto_state *state = ctx->cipher_data;

	struct session_op *sess = &state->d_sess;

	int cipher;

	if ((cipher = cipher_nid_to_cryptodev(ctx->cipher->nid)) == NID_undef)

		return (0);

	if (ctx->cipher->iv_len > cryptodev_max_iv(cipher))

		return (0);

	if (!cryptodev_key_length_valid(cipher, ctx->key_len))

		return (0);

	memset(sess, 0, sizeof(struct session_op));

	if ((state->d_fd = get_dev_crypto()) < 0)

		return (0);

	sess->key = (unsigned char *)key;

	sess->keylen = ctx->key_len;

	sess->cipher = cipher;

	if (ioctl(state->d_fd, CIOCGSESSION, sess) == -1) {

		close(state->d_fd);

		state->d_fd = -1;

		return (0);

	}

	return (1);

}

/*

 * free anything we allocated earlier when initting a

 * session, and close the session.

 */

static int

cryptodev_cleanup(EVP_CIPHER_CTX *ctx)

{

	int ret = 0;

	struct dev_crypto_state *state = ctx->cipher_data;

	struct session_op *sess = &state->d_sess;

	if (state->d_fd < 0)

		return (0);

	/* XXX if this ioctl fails, someting's wrong. the invoker

	 * may have called us with a bogus ctx, or we could

	 * have a device that for whatever reason just doesn't

	 * want to play ball - it's not clear what's right

	 * here - should this be an error? should it just

	 * increase a counter, hmm. For right now, we return

	 * 0 - I don't believe that to be "right". we could

	 * call the gorpy openssl lib error handlers that

	 * print messages to users of the library. hmm..

	 */

	if (ioctl(state->d_fd, CIOCFSESSION, &sess->ses) == -1) {

		ret = 0;

	} else {

		ret = 1;

	}

	close(state->d_fd);

	state->d_fd = -1;

	return (ret);

}

/*

 * libcrypto EVP stuff - this is how we get wired to EVP so the engine

 * gets called when libcrypto requests a cipher NID.

 */

/* DES CBC EVP */

const EVP_CIPHER cryptodev_des_cbc = {

	NID_des_cbc,

	8, 8, 8,

	EVP_CIPH_CBC_MODE,

	cryptodev_init_key,

	cryptodev_cipher,

	cryptodev_cleanup,

	sizeof(struct dev_crypto_state),

	EVP_CIPHER_set_asn1_iv,

	EVP_CIPHER_get_asn1_iv,

	NULL

};

/* 3DES CBC EVP */

const EVP_CIPHER cryptodev_3des_cbc = {

	NID_des_ede3_cbc,

	8, 24, 8,

	EVP_CIPH_CBC_MODE,

	cryptodev_init_key,

	cryptodev_cipher,

	cryptodev_cleanup,

	sizeof(struct dev_crypto_state),

	EVP_CIPHER_set_asn1_iv,

	EVP_CIPHER_get_asn1_iv,

	NULL

};

const EVP_CIPHER cryptodev_bf_cbc = {

	NID_bf_cbc,