Step 9 of move of engines: rename crypto/engine/hw_cryptodev.c to

[thirdparty/openssl.git] / crypto / engine / eng_cryptodev.c

/*
 * 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.
 * 3. Neither the name of the author nor the names of contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * 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>

#ifndef __OpenBSD__

void
ENGINE_load_cryptodev(void)
{
        /* This is a NOP unless __OpenBSD__ is defined */
        return;
}

#else /* __OpenBSD__ */

#include <sys/types.h>
#include <sys/param.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);
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) {
                *nids = 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) {
                *nids = 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,
        8, 16, 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_cast_cbc = {
        NID_cast5_cbc,
        8, 16, 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_aes_cbc = {
        NID_aes_128_cbc,
        16, 16, 16,
        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
};

/*
 * Registered by the ENGINE when used to find out how to deal with
 * a particular NID in the ENGINE. this says what we'll do at the
 * top level - note, that list is restricted by what we answer with
 */
static int
cryptodev_engine_ciphers(ENGINE *e, const EVP_CIPHER **cipher,
    const int **nids, int nid)
{
        if (!cipher)
                return (cryptodev_usable_ciphers(nids));

        switch (nid) {
        case NID_des_ede3_cbc:
                *cipher = &cryptodev_3des_cbc;
                break;
        case NID_des_cbc:
                *cipher = &cryptodev_des_cbc;
                break;
        case NID_bf_cbc:
                *cipher = &cryptodev_bf_cbc;
                break;
        case NID_cast5_cbc:
                *cipher = &cryptodev_cast_cbc;
                break;
        case NID_aes_128_cbc:
                *cipher = &cryptodev_aes_cbc;
                break;
        default:
                *cipher = NULL;
                break;
        }
        return (*cipher != NULL);
}

static int
cryptodev_engine_digests(ENGINE *e, const EVP_MD **digest,
    const int **nids, int nid)
{
        if (!digest)
                return (cryptodev_usable_digests(nids));

        switch (nid) {
        case NID_md5:
                *digest = NULL; /* need to make a clean md5 critter */
                break;
        default:
                *digest = NULL;
                break;
        }
        return (*digest != NULL);
}

/*
 * Convert a BIGNUM to the representation that /dev/crypto needs.
 * Upon completion of use, the caller is responsible for freeing
 * crp->crp_p.
 */
static int
bn2crparam(const BIGNUM *a, struct crparam *crp)
{
        int i, j, k;
        ssize_t words, bytes, bits;
        u_char *b;

        crp->crp_p = NULL;
        crp->crp_nbits = 0;

        bits = BN_num_bits(a);
        bytes = (bits + 7) / 8;

        b = malloc(bytes);
        if (b == NULL)
                return (1);

        crp->crp_p = b;
        crp->crp_nbits = bits;

        for (i = 0, j = 0; i < a->top; i++) {
                for (k = 0; k < BN_BITS2 / 8; k++) {
                        if ((j + k) >= bytes)
                                return (0);
                        b[j + k] = a->d[i] >> (k * 8);
                }
                j += BN_BITS2 / 8;
        }
        return (0);
}

/* Convert a /dev/crypto parameter to a BIGNUM */
static int
crparam2bn(struct crparam *crp, BIGNUM *a)
{
        u_int8_t *pd;
        int i, bytes;

        bytes = (crp->crp_nbits + 7) / 8;

        if (bytes == 0)
                return (-1);

        if ((pd = (u_int8_t *) malloc(bytes)) == NULL)
                return (-1);

        for (i = 0; i < bytes; i++)
                pd[i] = crp->crp_p[bytes - i - 1];

        BN_bin2bn(pd, bytes, a);
        free(pd);

        return (0);
}

static void
zapparams(struct crypt_kop *kop)
{
        int i;

        for (i = 0; i <= kop->crk_iparams + kop->crk_oparams; i++) {
                if (kop->crk_param[i].crp_p)
                        free(kop->crk_param[i].crp_p);
                kop->crk_param[i].crp_p = NULL;
                kop->crk_param[i].crp_nbits = 0;
        }
}

static int
cryptodev_asym(struct crypt_kop *kop, int rlen, BIGNUM *r, int slen, BIGNUM *s)
{
        int fd, ret = -1;

        if ((fd = get_asym_dev_crypto()) < 0)
                return (ret);

        if (r) {
                kop->crk_param[kop->crk_iparams].crp_p = calloc(rlen, sizeof(char));
                kop->crk_param[kop->crk_iparams].crp_nbits = rlen * 8;
                kop->crk_oparams++;
        }
        if (s) {
                kop->crk_param[kop->crk_iparams+1].crp_p = calloc(slen, sizeof(char));
                kop->crk_param[kop->crk_iparams+1].crp_nbits = slen * 8;
                kop->crk_oparams++;
        }

        if (ioctl(fd, CIOCKEY, kop) == 0) {
                if (r)
                        crparam2bn(&kop->crk_param[kop->crk_iparams], r);
                if (s)
                        crparam2bn(&kop->crk_param[kop->crk_iparams+1], s);
                ret = 0;
        }

        return (ret);
}

static int
cryptodev_bn_mod_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
    const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *in_mont)
{
        struct crypt_kop kop;
        int ret = 1;

        /* Currently, we know we can do mod exp iff we can do any
         * asymmetric operations at all.
         */
        if (cryptodev_asymfeat == 0) {
                ret = BN_mod_exp(r, a, p, m, ctx);
                return (ret);
        }

        memset(&kop, 0, sizeof kop);
        kop.crk_op = CRK_MOD_EXP;

        /* inputs: a^p % m */
        if (bn2crparam(a, &kop.crk_param[0]))
                goto err;
        if (bn2crparam(p, &kop.crk_param[1]))
                goto err;
        if (bn2crparam(m, &kop.crk_param[2]))
                goto err;
        kop.crk_iparams = 3;

        if (cryptodev_asym(&kop, BN_num_bytes(m), r, 0, NULL) == -1) {
                const RSA_METHOD *meth = RSA_PKCS1_SSLeay();
                ret = meth->bn_mod_exp(r, a, p, m, ctx, in_mont);
        }
err:
        zapparams(&kop);
        return (ret);
}

static int
cryptodev_rsa_nocrt_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa)
{
        int r;
        BN_CTX *ctx;

        ctx = BN_CTX_new();
        r = cryptodev_bn_mod_exp(r0, I, rsa->d, rsa->n, ctx, NULL);
        BN_CTX_free(ctx);
        return (r);
}

static int
cryptodev_rsa_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa)
{
        struct crypt_kop kop;
        int ret = 1;

        if (!rsa->p || !rsa->q || !rsa->dmp1 || !rsa->dmq1 || !rsa->iqmp) {
                /* XXX 0 means failure?? */
                return (0);
        }

        memset(&kop, 0, sizeof kop);
        kop.crk_op = CRK_MOD_EXP_CRT;
        /* inputs: rsa->p rsa->q I rsa->dmp1 rsa->dmq1 rsa->iqmp */
        if (bn2crparam(rsa->p, &kop.crk_param[0]))
                goto err;
        if (bn2crparam(rsa->q, &kop.crk_param[1]))
                goto err;
        if (bn2crparam(I, &kop.crk_param[2]))
                goto err;
        if (bn2crparam(rsa->dmp1, &kop.crk_param[3]))
                goto err;
        if (bn2crparam(rsa->dmq1, &kop.crk_param[4]))
                goto err;
        if (bn2crparam(rsa->iqmp, &kop.crk_param[5]))
                goto err;
        kop.crk_iparams = 6;

        if (cryptodev_asym(&kop, BN_num_bytes(rsa->n), r0, 0, NULL) == -1) {
                const RSA_METHOD *meth = RSA_PKCS1_SSLeay();
                ret = (*meth->rsa_mod_exp)(r0, I, rsa);
        }
err:
        zapparams(&kop);
        return (ret);
}

static RSA_METHOD cryptodev_rsa = {
        "cryptodev RSA method",
        NULL,                           /* rsa_pub_enc */
        NULL,                           /* rsa_pub_dec */
        NULL,                           /* rsa_priv_enc */
        NULL,                           /* rsa_priv_dec */
        NULL,
        NULL,
        NULL,                           /* init */
        NULL,                           /* finish */
        0,                              /* flags */
        NULL,                           /* app_data */
        NULL,                           /* rsa_sign */
        NULL                            /* rsa_verify */
};

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)
{
        return (cryptodev_bn_mod_exp(r, a, p, m, 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)
{
        BIGNUM t2;
        int ret = 0;

        BN_init(&t2);

        /* v = ( g^u1 * y^u2 mod p ) mod q */
        /* let t1 = g ^ u1 mod p */
        ret = 0;

        if (!dsa->meth->bn_mod_exp(dsa,t1,dsa->g,u1,dsa->p,ctx,mont))
                goto err;

        /* let t2 = y ^ u2 mod p */
        if (!dsa->meth->bn_mod_exp(dsa,&t2,dsa->pub_key,u2,dsa->p,ctx,mont))
                goto err;
        /* let u1 = t1 * t2 mod p */
        if (!BN_mod_mul(u1,t1,&t2,dsa->p,ctx))
                goto err;

        BN_copy(t1,u1);

        ret = 1;
err:
        BN_free(&t2);
        return(ret);
}

static DSA_SIG *
cryptodev_dsa_do_sign(const unsigned char *dgst, int dlen, DSA *dsa)
{
        struct crypt_kop kop;
        BIGNUM *r = NULL, *s = NULL;
        DSA_SIG *dsaret = NULL;

        if ((r = BN_new()) == NULL)
                goto err;
        if ((s = BN_new()) == NULL) {
                BN_free(r);
                goto err;
        }

        printf("bar\n");
        memset(&kop, 0, sizeof kop);
        kop.crk_op = CRK_DSA_SIGN;

        /* inputs: dgst dsa->p dsa->q dsa->g dsa->priv_key */
        kop.crk_param[0].crp_p = (caddr_t)dgst;
        kop.crk_param[0].crp_nbits = dlen * 8;
        if (bn2crparam(dsa->p, &kop.crk_param[1]))
                goto err;
        if (bn2crparam(dsa->q, &kop.crk_param[2]))
                goto err;
        if (bn2crparam(dsa->g, &kop.crk_param[3]))
                goto err;
        if (bn2crparam(dsa->priv_key, &kop.crk_param[4]))
                goto err;
        kop.crk_iparams = 5;

        if (cryptodev_asym(&kop, BN_num_bytes(dsa->q), r,
            BN_num_bytes(dsa->q), s) == 0) {
                dsaret = DSA_SIG_new();
                dsaret->r = r;
                dsaret->s = s;
        } else {
                const DSA_METHOD *meth = DSA_OpenSSL();
                BN_free(r);
                BN_free(s);
                dsaret = (meth->dsa_do_sign)(dgst, dlen, dsa);
        }
err:
        kop.crk_param[0].crp_p = NULL;
        zapparams(&kop);
        return (dsaret);
}

static int
cryptodev_dsa_verify(const unsigned char *dgst, int dlen,
    DSA_SIG *sig, DSA *dsa)
{
        struct crypt_kop kop;
        int dsaret = 1;

        memset(&kop, 0, sizeof kop);
        kop.crk_op = CRK_DSA_VERIFY;

        /* inputs: dgst dsa->p dsa->q dsa->g dsa->pub_key sig->r sig->s */
        kop.crk_param[0].crp_p = (caddr_t)dgst;
        kop.crk_param[0].crp_nbits = dlen * 8;
        if (bn2crparam(dsa->p, &kop.crk_param[1]))
                goto err;
        if (bn2crparam(dsa->q, &kop.crk_param[2]))
                goto err;
        if (bn2crparam(dsa->g, &kop.crk_param[3]))
                goto err;
        if (bn2crparam(dsa->pub_key, &kop.crk_param[4]))
                goto err;
        if (bn2crparam(sig->r, &kop.crk_param[5]))
                goto err;
        if (bn2crparam(sig->s, &kop.crk_param[6]))
                goto err;
        kop.crk_iparams = 7;

        if (cryptodev_asym(&kop, 0, NULL, 0, NULL) == 0) {
                dsaret = kop.crk_status;
        } else {
                const DSA_METHOD *meth = DSA_OpenSSL();

                dsaret = (meth->dsa_do_verify)(dgst, dlen, sig, dsa);
        }
err:
        kop.crk_param[0].crp_p = NULL;
        zapparams(&kop);
        return (dsaret);
}

static DSA_METHOD cryptodev_dsa = {
        "cryptodev DSA method",
        NULL,
        NULL,                           /* dsa_sign_setup */
        NULL,
        NULL,                           /* dsa_mod_exp */
        NULL,
        NULL,                           /* init */
        NULL,                           /* finish */
        0,      /* flags */
        NULL    /* app_data */
};

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)
{
        return (cryptodev_bn_mod_exp(r, a, p, m, ctx, m_ctx));
}

static int
cryptodev_dh_compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
{
        struct crypt_kop kop;
        int dhret = 1;
        int fd, keylen;

        if ((fd = get_asym_dev_crypto()) < 0) {
                const DH_METHOD *meth = DH_OpenSSL();

                return ((meth->compute_key)(key, pub_key, dh));
        }

        keylen = BN_num_bits(dh->p);

        memset(&kop, 0, sizeof kop);
        kop.crk_op = CRK_DH_COMPUTE_KEY;

        /* inputs: dh->priv_key pub_key dh->p key */
        if (bn2crparam(dh->priv_key, &kop.crk_param[0]))
                goto err;
        if (bn2crparam(pub_key, &kop.crk_param[1]))
                goto err;
        if (bn2crparam(dh->p, &kop.crk_param[2]))
                goto err;
        kop.crk_iparams = 3;

        kop.crk_param[3].crp_p = key;
        kop.crk_param[3].crp_nbits = keylen * 8;
        kop.crk_oparams = 1;

        if (ioctl(fd, CIOCKEY, &kop) == -1) {
                const DH_METHOD *meth = DH_OpenSSL();

                dhret = (meth->compute_key)(key, pub_key, dh);
        }
err:
        kop.crk_param[3].crp_p = NULL;
        zapparams(&kop);
        return (dhret);
}

static DH_METHOD cryptodev_dh = {
        "cryptodev DH method",
        NULL,                           /* cryptodev_dh_generate_key */
        NULL,
        NULL,
        NULL,
        NULL,
        0,      /* flags */
        NULL    /* app_data */
};

/*
 * ctrl right now is just a wrapper that doesn't do much
 * but I expect we'll want some options soon.
 */
static int
cryptodev_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f)())
{
        struct syslog_data sd = SYSLOG_DATA_INIT;

        switch (cmd) {
        default:
                syslog_r(LOG_ERR, &sd,
                    "cryptodev_ctrl: unknown command %d", cmd);
                break;
        }
        return (1);
}

void
ENGINE_load_cryptodev(void)
{
        ENGINE *engine = ENGINE_new();
        int fd;

        if (engine == NULL)
                return;
        if ((fd = get_dev_crypto()) < 0)
                return;

        /*
         * find out what asymmetric crypto algorithms we support
         */
        if (ioctl(fd, CIOCASYMFEAT, &cryptodev_asymfeat) == -1) {
                close(fd);
                return;
        }
        close(fd);

        if (!ENGINE_set_id(engine, "cryptodev") ||
            !ENGINE_set_name(engine, "OpenBSD cryptodev engine") ||
            !ENGINE_set_ciphers(engine, cryptodev_engine_ciphers) ||
            !ENGINE_set_digests(engine, cryptodev_engine_digests) ||
            !ENGINE_set_ctrl_function(engine, cryptodev_ctrl) ||
            !ENGINE_set_cmd_defns(engine, cryptodev_defns)) {
                ENGINE_free(engine);
                return;
        }

        if (ENGINE_set_RSA(engine, &cryptodev_rsa)) {
                const RSA_METHOD *rsa_meth = RSA_PKCS1_SSLeay();

                cryptodev_rsa.bn_mod_exp = rsa_meth->bn_mod_exp;
                cryptodev_rsa.rsa_mod_exp = rsa_meth->rsa_mod_exp;
                cryptodev_rsa.rsa_pub_enc = rsa_meth->rsa_pub_enc;
                cryptodev_rsa.rsa_pub_dec = rsa_meth->rsa_pub_dec;
                cryptodev_rsa.rsa_priv_enc = rsa_meth->rsa_priv_enc;
                cryptodev_rsa.rsa_priv_dec = rsa_meth->rsa_priv_dec;
                if (cryptodev_asymfeat & CRF_MOD_EXP) {
                        cryptodev_rsa.bn_mod_exp = cryptodev_bn_mod_exp;
                        if (cryptodev_asymfeat & CRF_MOD_EXP_CRT)
                                cryptodev_rsa.rsa_mod_exp =
                                    cryptodev_rsa_mod_exp;
                        else
                                cryptodev_rsa.rsa_mod_exp =
                                    cryptodev_rsa_nocrt_mod_exp;
                }
        }

        if (ENGINE_set_DSA(engine, &cryptodev_dsa)) {
                const DSA_METHOD *meth = DSA_OpenSSL();

                memcpy(&cryptodev_dsa, meth, sizeof(DSA_METHOD));
                if (cryptodev_asymfeat & CRF_DSA_SIGN)
                        cryptodev_dsa.dsa_do_sign = cryptodev_dsa_do_sign;
                if (cryptodev_asymfeat & CRF_MOD_EXP) {
                        cryptodev_dsa.bn_mod_exp = cryptodev_dsa_bn_mod_exp;
                        cryptodev_dsa.dsa_mod_exp = cryptodev_dsa_dsa_mod_exp;
                }
                if (cryptodev_asymfeat & CRF_DSA_VERIFY)
                        cryptodev_dsa.dsa_do_verify = cryptodev_dsa_verify;
        }

        if (ENGINE_set_DH(engine, &cryptodev_dh)){
                const DH_METHOD *dh_meth = DH_OpenSSL();

                cryptodev_dh.generate_key = dh_meth->generate_key;
                cryptodev_dh.compute_key = dh_meth->compute_key;
                cryptodev_dh.bn_mod_exp = dh_meth->bn_mod_exp;
                if (cryptodev_asymfeat & CRF_MOD_EXP) {
                        cryptodev_dh.bn_mod_exp = cryptodev_mod_exp_dh;
                        if (cryptodev_asymfeat & CRF_DH_COMPUTE_KEY)
                                cryptodev_dh.compute_key =
                                    cryptodev_dh_compute_key;
                }
        }

        ENGINE_add(engine);
        ENGINE_free(engine);
        ERR_clear_error();
}

#endif /* __OpenBSD__ */