openssl/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.
 *
 * 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>
#include <openssl/dsa.h>
#include <openssl/rsa.h>
#include <openssl/dh.h>
#include <openssl/err.h>

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

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,
                                       BN_CTX *ctx);
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,
    },
};

# if 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,
    },
};
# endif

/*
 * 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);
}

# if 0                          /* unused */
/*
 * 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);
}

# endif

/*
 * 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;
    const 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 = 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 = 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 = (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 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 = (char *)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)) {
        const RSA_METHOD *meth = RSA_PKCS1_SSLeay();
        printf("OCF asym process failed, Running in software\n");
        ret = meth->bn_mod_exp(r, a, p, m, ctx, in_mont);

    } else if (ECANCELED == kop.crk_status) {
        const RSA_METHOD *meth = RSA_PKCS1_SSLeay();
        printf("OCF hardware operation cancelled. Running in Software\n");
        ret = meth->bn_mod_exp(r, a, p, m, ctx, in_mont);
    }
    /* else cryptodev operation worked ok ==> ret = 1 */

 err:
    zapparams(&kop);
    return (ret);
}

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

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

static int
cryptodev_rsa_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
{
    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)) {
        const RSA_METHOD *meth = RSA_PKCS1_SSLeay();
        printf("OCF asym process failed, running in Software\n");
        ret = (*meth->rsa_mod_exp) (r0, I, rsa, ctx);

    } else if (ECANCELED == kop.crk_status) {
        const RSA_METHOD *meth = RSA_PKCS1_SSLeay();
        printf("OCF hardware operation cancelled. Running in Software\n");
        ret = (*meth->rsa_mod_exp) (r0, I, rsa, ctx);
    }
    /* else cryptodev operation worked ok ==> ret = 1 */

 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;
    }

    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) {
        /*
         * OCF success value is 0, if not zero, change dsaret to fail
         */
        if (0 != kop.crk_status)
            dsaret = 0;
    } 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 = (char *)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) ())
{
# ifdef HAVE_SYSLOG_R
    struct syslog_data sd = SYSLOG_DATA_INIT;
# endif

    switch (cmd) {
    default:
# ifdef HAVE_SYSLOG_R
        syslog_r(LOG_ERR, &sd, "cryptodev_ctrl: unknown command %d", cmd);
# else
        syslog(LOG_ERR, "cryptodev_ctrl: unknown command %d", cmd);
# endif
        break;
    }
    return (1);
}

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

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

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

    if (!ENGINE_set_id(engine, "cryptodev") ||
        !ENGINE_set_name(engine, "BSD 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                          /* HAVE_CRYPTODEV */