Reduce header interdependencies, initially in engine.h (the rest of the

[thirdparty/openssl.git] / engines / e_ubsec.c

/* crypto/engine/hw_ubsec.c */
/* Written by Geoff Thorpe (geoff@geoffthorpe.net) for the OpenSSL
 * project 2000.
 *
 * Cloned shamelessly by Joe Tardo. 
 */
/* ====================================================================
 * Copyright (c) 1999-2001 The OpenSSL Project.  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. All advertising materials mentioning features or use of this
 *    software must display the following acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
 *
 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For written permission, please contact
 *    licensing@OpenSSL.org.
 *
 * 5. Products derived from this software may not be called "OpenSSL"
 *    nor may "OpenSSL" appear in their names without prior written
 *    permission of the OpenSSL Project.
 *
 * 6. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
 *
 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
 * EXPRESSED 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 OpenSSL PROJECT OR
 * ITS 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.
 * ====================================================================
 *
 * This product includes cryptographic software written by Eric Young
 * (eay@cryptsoft.com).  This product includes software written by Tim
 * Hudson (tjh@cryptsoft.com).
 *
 */

#include <stdio.h>
#include <string.h>
#include <openssl/crypto.h>
#include <openssl/buffer.h>
#include <openssl/dso.h>
#include <openssl/engine.h>
#include <openssl/rsa.h>
#include <openssl/dsa.h>
#include <openssl/dh.h>

#ifndef OPENSSL_NO_HW
#ifndef OPENSSL_NO_HW_UBSEC

#ifdef FLAT_INC
#include "hw_ubsec.h"
#else
#include "vendor_defns/hw_ubsec.h"
#endif

#define UBSEC_LIB_NAME "ubsec engine"
#include "e_ubsec_err.c"

#define FAIL_TO_SOFTWARE -15

static int ubsec_destroy(ENGINE *e);
static int ubsec_init(ENGINE *e);
static int ubsec_finish(ENGINE *e);
static int ubsec_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f)(void));
static int ubsec_mod_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
                const BIGNUM *m, BN_CTX *ctx);
static int ubsec_mod_exp_crt(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
                        const BIGNUM *q, const BIGNUM *dp,
                        const BIGNUM *dq, const BIGNUM *qinv, BN_CTX *ctx);
#ifndef OPENSSL_NO_RSA
static int ubsec_rsa_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx);
#endif
static int ubsec_mod_exp_mont(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
                const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *m_ctx);
#ifndef OPENSSL_NO_DSA
#ifdef NOT_USED
static int ubsec_dsa_mod_exp(DSA *dsa, BIGNUM *rr, BIGNUM *a1,
                BIGNUM *p1, BIGNUM *a2, BIGNUM *p2, BIGNUM *m,
                BN_CTX *ctx, BN_MONT_CTX *in_mont);
static int ubsec_mod_exp_dsa(DSA *dsa, BIGNUM *r, BIGNUM *a,
                const BIGNUM *p, const BIGNUM *m, BN_CTX *ctx,
                BN_MONT_CTX *m_ctx);
#endif
static DSA_SIG *ubsec_dsa_do_sign(const unsigned char *dgst, int dlen, DSA *dsa);
static int ubsec_dsa_verify(const unsigned char *dgst, int dgst_len,
                                DSA_SIG *sig, DSA *dsa);
#endif
#ifndef OPENSSL_NO_DH
static int ubsec_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 ubsec_dh_compute_key(unsigned char *key,const BIGNUM *pub_key,DH *dh);
static int ubsec_dh_generate_key(DH *dh);
#endif

#ifdef NOT_USED
static int ubsec_rand_bytes(unsigned char *buf, int num);
static int ubsec_rand_status(void);
#endif

#define UBSEC_CMD_SO_PATH               ENGINE_CMD_BASE
static const ENGINE_CMD_DEFN ubsec_cmd_defns[] = {
        {UBSEC_CMD_SO_PATH,
                "SO_PATH",
                "Specifies the path to the 'ubsec' shared library",
                ENGINE_CMD_FLAG_STRING},
        {0, NULL, NULL, 0}
        };

#ifndef OPENSSL_NO_RSA
/* Our internal RSA_METHOD that we provide pointers to */
static RSA_METHOD ubsec_rsa =
        {
        "UBSEC RSA method",
        NULL,
        NULL,
        NULL,
        NULL,
        ubsec_rsa_mod_exp,
        ubsec_mod_exp_mont,
        NULL,
        NULL,
        0,
        NULL,
        NULL,
        NULL,
        NULL
        };
#endif

#ifndef OPENSSL_NO_DSA
/* Our internal DSA_METHOD that we provide pointers to */
static DSA_METHOD ubsec_dsa =
        {
        "UBSEC DSA method",
        ubsec_dsa_do_sign, /* dsa_do_sign */
        NULL, /* dsa_sign_setup */
        ubsec_dsa_verify, /* dsa_do_verify */
        NULL, /* ubsec_dsa_mod_exp */ /* dsa_mod_exp */
        NULL, /* ubsec_mod_exp_dsa */ /* bn_mod_exp */
        NULL, /* init */
        NULL, /* finish */
        0, /* flags */
        NULL, /* app_data */
        NULL, /* dsa_paramgen */
        NULL /* dsa_keygen */
        };
#endif

#ifndef OPENSSL_NO_DH
/* Our internal DH_METHOD that we provide pointers to */
static DH_METHOD ubsec_dh =
        {
        "UBSEC DH method",
        ubsec_dh_generate_key,
        ubsec_dh_compute_key,
        ubsec_mod_exp_dh,
        NULL,
        NULL,
        0,
        NULL,
        NULL
        };
#endif

/* Constants used when creating the ENGINE */
static const char *engine_ubsec_id = "ubsec";
static const char *engine_ubsec_name = "UBSEC hardware engine support";

/* This internal function is used by ENGINE_ubsec() and possibly by the
 * "dynamic" ENGINE support too */
static int bind_helper(ENGINE *e)
        {
#ifndef OPENSSL_NO_RSA
        const RSA_METHOD *meth1;
#endif
#ifndef OPENSSL_NO_DH
#ifndef HAVE_UBSEC_DH
        const DH_METHOD *meth3;
#endif /* HAVE_UBSEC_DH */
#endif
        if(!ENGINE_set_id(e, engine_ubsec_id) ||
                        !ENGINE_set_name(e, engine_ubsec_name) ||
#ifndef OPENSSL_NO_RSA
                        !ENGINE_set_RSA(e, &ubsec_rsa) ||
#endif
#ifndef OPENSSL_NO_DSA
                        !ENGINE_set_DSA(e, &ubsec_dsa) ||
#endif
#ifndef OPENSSL_NO_DH
                        !ENGINE_set_DH(e, &ubsec_dh) ||
#endif
                        !ENGINE_set_destroy_function(e, ubsec_destroy) ||
                        !ENGINE_set_init_function(e, ubsec_init) ||
                        !ENGINE_set_finish_function(e, ubsec_finish) ||
                        !ENGINE_set_ctrl_function(e, ubsec_ctrl) ||
                        !ENGINE_set_cmd_defns(e, ubsec_cmd_defns))
                return 0;

#ifndef OPENSSL_NO_RSA
        /* We know that the "PKCS1_SSLeay()" functions hook properly
         * to the Broadcom-specific mod_exp and mod_exp_crt so we use
         * those functions. NB: We don't use ENGINE_openssl() or
         * anything "more generic" because something like the RSAref
         * code may not hook properly, and if you own one of these
         * cards then you have the right to do RSA operations on it
         * anyway! */ 
        meth1 = RSA_PKCS1_SSLeay();
        ubsec_rsa.rsa_pub_enc = meth1->rsa_pub_enc;
        ubsec_rsa.rsa_pub_dec = meth1->rsa_pub_dec;
        ubsec_rsa.rsa_priv_enc = meth1->rsa_priv_enc;
        ubsec_rsa.rsa_priv_dec = meth1->rsa_priv_dec;
#endif

#ifndef OPENSSL_NO_DH
#ifndef HAVE_UBSEC_DH
        /* Much the same for Diffie-Hellman */
        meth3 = DH_OpenSSL();
        ubsec_dh.generate_key = meth3->generate_key;
        ubsec_dh.compute_key = meth3->compute_key;
#endif /* HAVE_UBSEC_DH */
#endif

        /* Ensure the ubsec error handling is set up */
        ERR_load_UBSEC_strings();
        return 1;
        }

#ifdef OPENSSL_NO_DYNAMIC_ENGINE
static ENGINE *engine_ubsec(void)
        {
        ENGINE *ret = ENGINE_new();
        if(!ret)
                return NULL;
        if(!bind_helper(ret))
                {
                ENGINE_free(ret);
                return NULL;
                }
        return ret;
        }

void ENGINE_load_ubsec(void)
        {
        /* Copied from eng_[openssl|dyn].c */
        ENGINE *toadd = engine_ubsec();
        if(!toadd) return;
        ENGINE_add(toadd);
        ENGINE_free(toadd);
        ERR_clear_error();
        }
#endif

/* This is a process-global DSO handle used for loading and unloading
 * the UBSEC library. NB: This is only set (or unset) during an
 * init() or finish() call (reference counts permitting) and they're
 * operating with global locks, so this should be thread-safe
 * implicitly. */

static DSO *ubsec_dso = NULL;

/* These are the function pointers that are (un)set when the library has
 * successfully (un)loaded. */

static t_UBSEC_ubsec_bytes_to_bits *p_UBSEC_ubsec_bytes_to_bits = NULL;
static t_UBSEC_ubsec_bits_to_bytes *p_UBSEC_ubsec_bits_to_bytes = NULL;
static t_UBSEC_ubsec_open *p_UBSEC_ubsec_open = NULL;
static t_UBSEC_ubsec_close *p_UBSEC_ubsec_close = NULL;
#ifndef OPENSSL_NO_DH
static t_UBSEC_diffie_hellman_generate_ioctl 
        *p_UBSEC_diffie_hellman_generate_ioctl = NULL;
static t_UBSEC_diffie_hellman_agree_ioctl *p_UBSEC_diffie_hellman_agree_ioctl = NULL;
#endif
/* #ifndef OPENSSL_NO_RSA */
static t_UBSEC_rsa_mod_exp_ioctl *p_UBSEC_rsa_mod_exp_ioctl = NULL;
static t_UBSEC_rsa_mod_exp_crt_ioctl *p_UBSEC_rsa_mod_exp_crt_ioctl = NULL;
/* #endif */
#ifndef OPENSSL_NO_DSA
static t_UBSEC_dsa_sign_ioctl *p_UBSEC_dsa_sign_ioctl = NULL;
static t_UBSEC_dsa_verify_ioctl *p_UBSEC_dsa_verify_ioctl = NULL;
#endif
static t_UBSEC_math_accelerate_ioctl *p_UBSEC_math_accelerate_ioctl = NULL;
static t_UBSEC_rng_ioctl *p_UBSEC_rng_ioctl = NULL;
static t_UBSEC_max_key_len_ioctl *p_UBSEC_max_key_len_ioctl = NULL;

static int max_key_len = 1024;  /* ??? */

/* 
 * These are the static string constants for the DSO file name and the function
 * symbol names to bind to. 
 */

static const char *UBSEC_LIBNAME = NULL;
static const char *get_UBSEC_LIBNAME(void)
        {
        if(UBSEC_LIBNAME)
                return UBSEC_LIBNAME;
        return "ubsec";
        }
static void free_UBSEC_LIBNAME(void)
        {
        if(UBSEC_LIBNAME)
                OPENSSL_free((void*)UBSEC_LIBNAME);
        UBSEC_LIBNAME = NULL;
        }
static long set_UBSEC_LIBNAME(const char *name)
        {
        free_UBSEC_LIBNAME();
        return (((UBSEC_LIBNAME = BUF_strdup(name)) != NULL) ? 1 : 0);
        }
static const char *UBSEC_F1 = "ubsec_bytes_to_bits";
static const char *UBSEC_F2 = "ubsec_bits_to_bytes";
static const char *UBSEC_F3 = "ubsec_open";
static const char *UBSEC_F4 = "ubsec_close";
#ifndef OPENSSL_NO_DH
static const char *UBSEC_F5 = "diffie_hellman_generate_ioctl";
static const char *UBSEC_F6 = "diffie_hellman_agree_ioctl";
#endif
/* #ifndef OPENSSL_NO_RSA */
static const char *UBSEC_F7 = "rsa_mod_exp_ioctl";
static const char *UBSEC_F8 = "rsa_mod_exp_crt_ioctl";
/* #endif */
#ifndef OPENSSL_NO_DSA
static const char *UBSEC_F9 = "dsa_sign_ioctl";
static const char *UBSEC_F10 = "dsa_verify_ioctl";
#endif
static const char *UBSEC_F11 = "math_accelerate_ioctl";
static const char *UBSEC_F12 = "rng_ioctl";
static const char *UBSEC_F13 = "ubsec_max_key_len_ioctl";

/* Destructor (complements the "ENGINE_ubsec()" constructor) */
static int ubsec_destroy(ENGINE *e)
        {
        free_UBSEC_LIBNAME();
        ERR_unload_UBSEC_strings();
        return 1;
        }

/* (de)initialisation functions. */
static int ubsec_init(ENGINE *e)
        {
        t_UBSEC_ubsec_bytes_to_bits *p1;
        t_UBSEC_ubsec_bits_to_bytes *p2;
        t_UBSEC_ubsec_open *p3;
        t_UBSEC_ubsec_close *p4;
#ifndef OPENSSL_NO_DH
        t_UBSEC_diffie_hellman_generate_ioctl *p5;
        t_UBSEC_diffie_hellman_agree_ioctl *p6;
#endif
/* #ifndef OPENSSL_NO_RSA */
        t_UBSEC_rsa_mod_exp_ioctl *p7;
        t_UBSEC_rsa_mod_exp_crt_ioctl *p8;
/* #endif */
#ifndef OPENSSL_NO_DSA
        t_UBSEC_dsa_sign_ioctl *p9;
        t_UBSEC_dsa_verify_ioctl *p10;
#endif
        t_UBSEC_math_accelerate_ioctl *p11;
        t_UBSEC_rng_ioctl *p12;
        t_UBSEC_max_key_len_ioctl *p13;
        int fd = 0;

        if(ubsec_dso != NULL)
                {
                UBSECerr(UBSEC_F_UBSEC_INIT, UBSEC_R_ALREADY_LOADED);
                goto err;
                }
        /* 
         * Attempt to load libubsec.so/ubsec.dll/whatever. 
         */
        ubsec_dso = DSO_load(NULL, get_UBSEC_LIBNAME(), NULL, 0);
        if(ubsec_dso == NULL)
                {
                UBSECerr(UBSEC_F_UBSEC_INIT, UBSEC_R_DSO_FAILURE);
                goto err;
                }

        if (
        !(p1 = (t_UBSEC_ubsec_bytes_to_bits *) DSO_bind_func(ubsec_dso, UBSEC_F1)) ||
        !(p2 = (t_UBSEC_ubsec_bits_to_bytes *) DSO_bind_func(ubsec_dso, UBSEC_F2)) ||
        !(p3 = (t_UBSEC_ubsec_open *) DSO_bind_func(ubsec_dso, UBSEC_F3)) ||
        !(p4 = (t_UBSEC_ubsec_close *) DSO_bind_func(ubsec_dso, UBSEC_F4)) ||
#ifndef OPENSSL_NO_DH
        !(p5 = (t_UBSEC_diffie_hellman_generate_ioctl *) 
                                DSO_bind_func(ubsec_dso, UBSEC_F5)) ||
        !(p6 = (t_UBSEC_diffie_hellman_agree_ioctl *) 
                                DSO_bind_func(ubsec_dso, UBSEC_F6)) ||
#endif
/* #ifndef OPENSSL_NO_RSA */
        !(p7 = (t_UBSEC_rsa_mod_exp_ioctl *) DSO_bind_func(ubsec_dso, UBSEC_F7)) ||
        !(p8 = (t_UBSEC_rsa_mod_exp_crt_ioctl *) DSO_bind_func(ubsec_dso, UBSEC_F8)) ||
/* #endif */
#ifndef OPENSSL_NO_DSA
        !(p9 = (t_UBSEC_dsa_sign_ioctl *) DSO_bind_func(ubsec_dso, UBSEC_F9)) ||
        !(p10 = (t_UBSEC_dsa_verify_ioctl *) DSO_bind_func(ubsec_dso, UBSEC_F10)) ||
#endif
        !(p11 = (t_UBSEC_math_accelerate_ioctl *) 
                                DSO_bind_func(ubsec_dso, UBSEC_F11)) ||
        !(p12 = (t_UBSEC_rng_ioctl *) DSO_bind_func(ubsec_dso, UBSEC_F12)) ||
        !(p13 = (t_UBSEC_max_key_len_ioctl *) DSO_bind_func(ubsec_dso, UBSEC_F13)))
                {
                UBSECerr(UBSEC_F_UBSEC_INIT, UBSEC_R_DSO_FAILURE);
                goto err;
                }

        /* Copy the pointers */
        p_UBSEC_ubsec_bytes_to_bits = p1;
        p_UBSEC_ubsec_bits_to_bytes = p2;
        p_UBSEC_ubsec_open = p3;
        p_UBSEC_ubsec_close = p4;
#ifndef OPENSSL_NO_DH
        p_UBSEC_diffie_hellman_generate_ioctl = p5;
        p_UBSEC_diffie_hellman_agree_ioctl = p6;
#endif
#ifndef OPENSSL_NO_RSA
        p_UBSEC_rsa_mod_exp_ioctl = p7;
        p_UBSEC_rsa_mod_exp_crt_ioctl = p8;
#endif
#ifndef OPENSSL_NO_DSA
        p_UBSEC_dsa_sign_ioctl = p9;
        p_UBSEC_dsa_verify_ioctl = p10;
#endif
        p_UBSEC_math_accelerate_ioctl = p11;
        p_UBSEC_rng_ioctl = p12;
        p_UBSEC_max_key_len_ioctl = p13;

        /* Perform an open to see if there's actually any unit running. */
        if (((fd = p_UBSEC_ubsec_open(UBSEC_KEY_DEVICE_NAME)) > 0) && (p_UBSEC_max_key_len_ioctl(fd, &max_key_len) == 0))
        {
           p_UBSEC_ubsec_close(fd);
           return 1;
        }
        else
        {
          UBSECerr(UBSEC_F_UBSEC_INIT, UBSEC_R_UNIT_FAILURE);
        }

err:
        if(ubsec_dso)
                DSO_free(ubsec_dso);
        p_UBSEC_ubsec_bytes_to_bits = NULL;
        p_UBSEC_ubsec_bits_to_bytes = NULL;
        p_UBSEC_ubsec_open = NULL;
        p_UBSEC_ubsec_close = NULL;
#ifndef OPENSSL_NO_DH
        p_UBSEC_diffie_hellman_generate_ioctl = NULL;
        p_UBSEC_diffie_hellman_agree_ioctl = NULL;
#endif
#ifndef OPENSSL_NO_RSA
        p_UBSEC_rsa_mod_exp_ioctl = NULL;
        p_UBSEC_rsa_mod_exp_crt_ioctl = NULL;
#endif
#ifndef OPENSSL_NO_DSA
        p_UBSEC_dsa_sign_ioctl = NULL;
        p_UBSEC_dsa_verify_ioctl = NULL;
#endif
        p_UBSEC_math_accelerate_ioctl = NULL;
        p_UBSEC_rng_ioctl = NULL;
        p_UBSEC_max_key_len_ioctl = NULL;

        return 0;
        }

static int ubsec_finish(ENGINE *e)
        {
        free_UBSEC_LIBNAME();
        if(ubsec_dso == NULL)
                {
                UBSECerr(UBSEC_F_UBSEC_FINISH, UBSEC_R_NOT_LOADED);
                return 0;
                }
        if(!DSO_free(ubsec_dso))
                {
                UBSECerr(UBSEC_F_UBSEC_FINISH, UBSEC_R_DSO_FAILURE);
                return 0;
                }
        ubsec_dso = NULL;
        p_UBSEC_ubsec_bytes_to_bits = NULL;
        p_UBSEC_ubsec_bits_to_bytes = NULL;
        p_UBSEC_ubsec_open = NULL;
        p_UBSEC_ubsec_close = NULL;
#ifndef OPENSSL_NO_DH
        p_UBSEC_diffie_hellman_generate_ioctl = NULL;
        p_UBSEC_diffie_hellman_agree_ioctl = NULL;
#endif
#ifndef OPENSSL_NO_RSA
        p_UBSEC_rsa_mod_exp_ioctl = NULL;
        p_UBSEC_rsa_mod_exp_crt_ioctl = NULL;
#endif
#ifndef OPENSSL_NO_DSA
        p_UBSEC_dsa_sign_ioctl = NULL;
        p_UBSEC_dsa_verify_ioctl = NULL;
#endif
        p_UBSEC_math_accelerate_ioctl = NULL;
        p_UBSEC_rng_ioctl = NULL;
        p_UBSEC_max_key_len_ioctl = NULL;
        return 1;
        }

static int ubsec_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f)(void))
        {
        int initialised = ((ubsec_dso == NULL) ? 0 : 1);
        switch(cmd)
                {
        case UBSEC_CMD_SO_PATH:
                if(p == NULL)
                        {
                        UBSECerr(UBSEC_F_UBSEC_CTRL,ERR_R_PASSED_NULL_PARAMETER);
                        return 0;
                        }
                if(initialised)
                        {
                        UBSECerr(UBSEC_F_UBSEC_CTRL,UBSEC_R_ALREADY_LOADED);
                        return 0;
                        }
                return set_UBSEC_LIBNAME((const char *)p);
        default:
                break;
                }
        UBSECerr(UBSEC_F_UBSEC_CTRL,UBSEC_R_CTRL_COMMAND_NOT_IMPLEMENTED);
        return 0;
        }

static int ubsec_mod_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
                const BIGNUM *m, BN_CTX *ctx)
        {
        int     y_len = 0;
        int     fd;

        if(ubsec_dso == NULL)
        {
                UBSECerr(UBSEC_F_UBSEC_MOD_EXP, UBSEC_R_NOT_LOADED);
                return 0;
        }

        /* Check if hardware can't handle this argument. */
        y_len = BN_num_bits(m);
        if (y_len > max_key_len) {
                UBSECerr(UBSEC_F_UBSEC_MOD_EXP, UBSEC_R_SIZE_TOO_LARGE_OR_TOO_SMALL);
                return BN_mod_exp(r, a, p, m, ctx);
        } 

        if(!bn_wexpand(r, m->top))
        {
                UBSECerr(UBSEC_F_UBSEC_MOD_EXP, UBSEC_R_BN_EXPAND_FAIL);
                return 0;
        }

        if ((fd = p_UBSEC_ubsec_open(UBSEC_KEY_DEVICE_NAME)) <= 0) {
                fd = 0;
                UBSECerr(UBSEC_F_UBSEC_INIT, UBSEC_R_UNIT_FAILURE);
                return BN_mod_exp(r, a, p, m, ctx);
        }

        if (p_UBSEC_rsa_mod_exp_ioctl(fd, (unsigned char *)a->d, BN_num_bits(a),
                (unsigned char *)m->d, BN_num_bits(m), (unsigned char *)p->d, 
                BN_num_bits(p), (unsigned char *)r->d, &y_len) != 0)
        {
                UBSECerr(UBSEC_F_UBSEC_MOD_EXP, UBSEC_R_REQUEST_FAILED);
                p_UBSEC_ubsec_close(fd);

                return BN_mod_exp(r, a, p, m, ctx);
        }

        p_UBSEC_ubsec_close(fd);

        r->top = (BN_num_bits(m)+BN_BITS2-1)/BN_BITS2;
        return 1;
        }

#ifndef OPENSSL_NO_RSA
static int ubsec_rsa_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
        {
        int to_return = 0;

        if(!rsa->p || !rsa->q || !rsa->dmp1 || !rsa->dmq1 || !rsa->iqmp)
                {
                UBSECerr(UBSEC_F_UBSEC_RSA_MOD_EXP, UBSEC_R_MISSING_KEY_COMPONENTS);
                goto err;
                }

        to_return = ubsec_mod_exp_crt(r0, I, rsa->p, rsa->q, rsa->dmp1,
                    rsa->dmq1, rsa->iqmp, ctx);
        if (to_return == FAIL_TO_SOFTWARE)
        {
          /*
           * Do in software as hardware failed.
           */
           const RSA_METHOD *meth = RSA_PKCS1_SSLeay();
           to_return = (*meth->rsa_mod_exp)(r0, I, rsa, ctx);
        }
err:
        return to_return;
        }
#endif

static int ubsec_mod_exp_crt(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
                        const BIGNUM *q, const BIGNUM *dp,
                        const BIGNUM *dq, const BIGNUM *qinv, BN_CTX *ctx)
        {
        int     y_len,
                m_len,
                fd;

        m_len = BN_num_bytes(p) + BN_num_bytes(q) + 1;
        y_len = BN_num_bits(p) + BN_num_bits(q);

        /* Check if hardware can't handle this argument. */
        if (y_len > max_key_len) {
                UBSECerr(UBSEC_F_UBSEC_MOD_EXP, UBSEC_R_SIZE_TOO_LARGE_OR_TOO_SMALL);
                return FAIL_TO_SOFTWARE;
        } 

        if (!bn_wexpand(r, p->top + q->top + 1)) {
                UBSECerr(UBSEC_F_UBSEC_RSA_MOD_EXP_CRT, UBSEC_R_BN_EXPAND_FAIL);
                return 0;
        }

        if ((fd = p_UBSEC_ubsec_open(UBSEC_KEY_DEVICE_NAME)) <= 0) {
                fd = 0;
                UBSECerr(UBSEC_F_UBSEC_INIT, UBSEC_R_UNIT_FAILURE);
                return FAIL_TO_SOFTWARE;
        }

        if (p_UBSEC_rsa_mod_exp_crt_ioctl(fd,
                (unsigned char *)a->d, BN_num_bits(a), 
                (unsigned char *)qinv->d, BN_num_bits(qinv),
                (unsigned char *)dp->d, BN_num_bits(dp),
                (unsigned char *)p->d, BN_num_bits(p),
                (unsigned char *)dq->d, BN_num_bits(dq),
                (unsigned char *)q->d, BN_num_bits(q),
                (unsigned char *)r->d,  &y_len) != 0) {
                UBSECerr(UBSEC_F_UBSEC_MOD_EXP, UBSEC_R_REQUEST_FAILED);
                p_UBSEC_ubsec_close(fd);
                return FAIL_TO_SOFTWARE;
        }

        p_UBSEC_ubsec_close(fd);

        r->top = (BN_num_bits(p) + BN_num_bits(q) + BN_BITS2 - 1)/BN_BITS2;
        return 1;
}

#ifndef OPENSSL_NO_DSA
#ifdef NOT_USED
static int ubsec_dsa_mod_exp(DSA *dsa, BIGNUM *rr, BIGNUM *a1,
                BIGNUM *p1, BIGNUM *a2, BIGNUM *p2, BIGNUM *m,
                BN_CTX *ctx, BN_MONT_CTX *in_mont)
        {
        BIGNUM t;
        int to_return = 0;
 
        BN_init(&t);
        /* let rr = a1 ^ p1 mod m */
        if (!ubsec_mod_exp(rr,a1,p1,m,ctx)) goto end;
        /* let t = a2 ^ p2 mod m */
        if (!ubsec_mod_exp(&t,a2,p2,m,ctx)) goto end;
        /* let rr = rr * t mod m */
        if (!BN_mod_mul(rr,rr,&t,m,ctx)) goto end;
        to_return = 1;
end:
        BN_free(&t);
        return to_return;
        }

static int ubsec_mod_exp_dsa(DSA *dsa, BIGNUM *r, BIGNUM *a,
                const BIGNUM *p, const BIGNUM *m, BN_CTX *ctx,
                BN_MONT_CTX *m_ctx)
        {
        return ubsec_mod_exp(r, a, p, m, ctx);
        }
#endif
#endif

/*
 * This function is aliased to mod_exp (with the mont stuff dropped).
 */
static int ubsec_mod_exp_mont(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
                const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *m_ctx)
        {
        int ret = 0;

#ifndef OPENSSL_NO_RSA
        /* Do in software if the key is too large for the hardware. */
        if (BN_num_bits(m) > max_key_len)
                {
                const RSA_METHOD *meth = RSA_PKCS1_SSLeay();
                ret = (*meth->bn_mod_exp)(r, a, p, m, ctx, m_ctx);
                }
        else
#endif
                {
                ret = ubsec_mod_exp(r, a, p, m, ctx);
                }
        
        return ret;
        }

#ifndef OPENSSL_NO_DH
/* This function is aliased to mod_exp (with the dh and mont dropped). */
static int ubsec_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 ubsec_mod_exp(r, a, p, m, ctx);
        }
#endif

#ifndef OPENSSL_NO_DSA
static DSA_SIG *ubsec_dsa_do_sign(const unsigned char *dgst, int dlen, DSA *dsa)
        {
        DSA_SIG *to_return = NULL;
        int s_len = 160, r_len = 160, d_len, fd;
        BIGNUM m, *r=NULL, *s=NULL;

        BN_init(&m);

        s = BN_new();
        r = BN_new();
        if ((s == NULL) || (r==NULL))
                goto err;

        d_len = p_UBSEC_ubsec_bytes_to_bits((unsigned char *)dgst, dlen);

        if(!bn_wexpand(r, (160+BN_BITS2-1)/BN_BITS2) ||
           (!bn_wexpand(s, (160+BN_BITS2-1)/BN_BITS2))) {
                UBSECerr(UBSEC_F_UBSEC_DSA_SIGN, UBSEC_R_BN_EXPAND_FAIL);
                goto err;
        }

        if (BN_bin2bn(dgst,dlen,&m) == NULL) {
                UBSECerr(UBSEC_F_UBSEC_DSA_SIGN, UBSEC_R_BN_EXPAND_FAIL);
                goto err;
        } 

        if ((fd = p_UBSEC_ubsec_open(UBSEC_KEY_DEVICE_NAME)) <= 0) {
                const DSA_METHOD *meth;
                fd = 0;
                UBSECerr(UBSEC_F_UBSEC_INIT, UBSEC_R_UNIT_FAILURE);
                meth = DSA_OpenSSL();
                to_return =  meth->dsa_do_sign(dgst, dlen, dsa);
                goto err;
        }

        if (p_UBSEC_dsa_sign_ioctl(fd, 0, /* compute hash before signing */
                (unsigned char *)dgst, d_len,
                NULL, 0,  /* compute random value */
                (unsigned char *)dsa->p->d, BN_num_bits(dsa->p), 
                (unsigned char *)dsa->q->d, BN_num_bits(dsa->q),
                (unsigned char *)dsa->g->d, BN_num_bits(dsa->g),
                (unsigned char *)dsa->priv_key->d, BN_num_bits(dsa->priv_key),
                (unsigned char *)r->d, &r_len,
                (unsigned char *)s->d, &s_len ) != 0) {
                const DSA_METHOD *meth;

                UBSECerr(UBSEC_F_UBSEC_DSA_SIGN, UBSEC_R_REQUEST_FAILED);
                p_UBSEC_ubsec_close(fd);
                meth = DSA_OpenSSL();
                to_return = meth->dsa_do_sign(dgst, dlen, dsa);

                goto err;
        }

        p_UBSEC_ubsec_close(fd);

        r->top = (160+BN_BITS2-1)/BN_BITS2;
        s->top = (160+BN_BITS2-1)/BN_BITS2;

        to_return = DSA_SIG_new();
        if(to_return == NULL) {
                UBSECerr(UBSEC_F_UBSEC_DSA_SIGN, UBSEC_R_BN_EXPAND_FAIL);
                goto err;
        }

        to_return->r = r;
        to_return->s = s;

err:
        if (!to_return) {
                if (r) BN_free(r);
                if (s) BN_free(s);
        }                                 
        BN_clear_free(&m);
        return to_return;
}

static int ubsec_dsa_verify(const unsigned char *dgst, int dgst_len,
                                DSA_SIG *sig, DSA *dsa)
        {
        int v_len, d_len;
        int to_return = 0;
        int fd;
        BIGNUM v;

        BN_init(&v);

        if(!bn_wexpand(&v, dsa->p->top)) {
                UBSECerr(UBSEC_F_UBSEC_DSA_VERIFY ,UBSEC_R_BN_EXPAND_FAIL);
                goto err;
        }

        v_len = BN_num_bits(dsa->p);

        d_len = p_UBSEC_ubsec_bytes_to_bits((unsigned char *)dgst, dgst_len);

        if ((fd = p_UBSEC_ubsec_open(UBSEC_KEY_DEVICE_NAME)) <= 0) {
                const DSA_METHOD *meth;
                fd = 0;
                UBSECerr(UBSEC_F_UBSEC_INIT, UBSEC_R_UNIT_FAILURE);
                meth = DSA_OpenSSL();
                to_return = meth->dsa_do_verify(dgst, dgst_len, sig, dsa);
                goto err;
        }

        if (p_UBSEC_dsa_verify_ioctl(fd, 0, /* compute hash before signing */
                (unsigned char *)dgst, d_len,
                (unsigned char *)dsa->p->d, BN_num_bits(dsa->p), 
                (unsigned char *)dsa->q->d, BN_num_bits(dsa->q),
                (unsigned char *)dsa->g->d, BN_num_bits(dsa->g),
                (unsigned char *)dsa->pub_key->d, BN_num_bits(dsa->pub_key),
                (unsigned char *)sig->r->d, BN_num_bits(sig->r),
                (unsigned char *)sig->s->d, BN_num_bits(sig->s),
                (unsigned char *)v.d, &v_len) != 0) {
                const DSA_METHOD *meth;
                UBSECerr(UBSEC_F_UBSEC_DSA_VERIFY , UBSEC_R_REQUEST_FAILED);
                p_UBSEC_ubsec_close(fd);

                meth = DSA_OpenSSL();
                to_return = meth->dsa_do_verify(dgst, dgst_len, sig, dsa);

                goto err;
        }

        p_UBSEC_ubsec_close(fd);

        to_return = 1;
err:
        BN_clear_free(&v);
        return to_return;
        }
#endif

#ifndef OPENSSL_NO_DH
static int ubsec_dh_compute_key (unsigned char *key,const BIGNUM *pub_key,DH *dh)
        {
        int      ret      = -1,
                 k_len,
                 fd;

        k_len = BN_num_bits(dh->p);

        if ((fd = p_UBSEC_ubsec_open(UBSEC_KEY_DEVICE_NAME)) <= 0)
                {
                const DH_METHOD *meth;
                ENGINEerr(UBSEC_F_UBSEC_INIT, UBSEC_R_UNIT_FAILURE);
                meth = DH_OpenSSL();
                ret = meth->compute_key(key, pub_key, dh);
                goto err;
                }

        if (p_UBSEC_diffie_hellman_agree_ioctl(fd,
                                               (unsigned char *)dh->priv_key->d, BN_num_bits(dh->priv_key),
                                               (unsigned char *)pub_key->d, BN_num_bits(pub_key),
                                               (unsigned char *)dh->p->d, BN_num_bits(dh->p),
                                               key, &k_len) != 0)
                {
                /* Hardware's a no go, failover to software */
                const DH_METHOD *meth;
                ENGINEerr(UBSEC_F_UBSEC_DH_COMPUTE_KEY, UBSEC_R_REQUEST_FAILED);
                p_UBSEC_ubsec_close(fd);

                meth = DH_OpenSSL();
                ret = meth->compute_key(key, pub_key, dh);

                goto err;
                }

        p_UBSEC_ubsec_close(fd);

        ret = p_UBSEC_ubsec_bits_to_bytes(k_len);
err:
        return ret;
        }

static int ubsec_dh_generate_key (DH *dh)
        {
        int      ret               = 0,
                 random_bits       = 0,
                 pub_key_len       = 0,
                 priv_key_len      = 0,
                 fd;
        BIGNUM   *pub_key          = NULL;
        BIGNUM   *priv_key         = NULL;

        /* 
         *  How many bits should Random x be? dh_key.c
         *  sets the range from 0 to num_bits(modulus) ???
         */

        if (dh->priv_key == NULL)
                {
                priv_key = BN_new();
                if (priv_key == NULL) goto err;
                priv_key_len = BN_num_bits(dh->p);
                bn_wexpand(priv_key, dh->p->top);
                do
                        if (!BN_rand_range(priv_key, dh->p)) goto err;
                while (BN_is_zero(priv_key));
                random_bits = BN_num_bits(priv_key);
                }
        else
                {
                priv_key = dh->priv_key;
                }

        if (dh->pub_key == NULL)
                {
                pub_key = BN_new();
                pub_key_len = BN_num_bits(dh->p);
                bn_wexpand(pub_key, dh->p->top);
                if(pub_key == NULL) goto err;
                }
        else
                {
                pub_key = dh->pub_key;
                }

        if ((fd = p_UBSEC_ubsec_open(UBSEC_KEY_DEVICE_NAME)) <= 0)
                {
                const DH_METHOD *meth;
                ENGINEerr(UBSEC_F_UBSEC_INIT, UBSEC_R_UNIT_FAILURE);
                meth = DH_OpenSSL();
                ret = meth->generate_key(dh);
                goto err;
                }

        if (p_UBSEC_diffie_hellman_generate_ioctl(fd,
                                                  (unsigned char *)priv_key->d, &priv_key_len,
                                                  (unsigned char *)pub_key->d,  &pub_key_len,
                                                  (unsigned char *)dh->g->d, BN_num_bits(dh->g),
                                                  (unsigned char *)dh->p->d, BN_num_bits(dh->p),
                                                  0, 0, random_bits) != 0)
                {
                /* Hardware's a no go, failover to software */
                const DH_METHOD *meth;

                ENGINEerr(UBSEC_F_UBSEC_DH_COMPUTE_KEY, UBSEC_R_REQUEST_FAILED);
                p_UBSEC_ubsec_close(fd);

                meth = DH_OpenSSL();
                ret = meth->generate_key(dh);

                goto err;
                }

        p_UBSEC_ubsec_close(fd);

        dh->pub_key = pub_key;
        dh->pub_key->top = (pub_key_len + BN_BITS2-1) / BN_BITS2;
        dh->priv_key = priv_key;
        dh->priv_key->top = (priv_key_len + BN_BITS2-1) / BN_BITS2;

        ret = 1;
err:
        return ret;
        }
#endif

#ifdef NOT_USED
static int ubsec_rand_bytes(unsigned char * buf,
                            int num)
        {
        int      ret      = 0,
                 fd;

        if ((fd = p_UBSEC_ubsec_open(UBSEC_KEY_DEVICE_NAME)) <= 0)
                {
                const RAND_METHOD *meth;
                ENGINEerr(UBSEC_F_UBSEC_INIT, UBSEC_R_UNIT_FAILURE);
                num = p_UBSEC_ubsec_bits_to_bytes(num);
                meth = RAND_SSLeay();
                meth->seed(buf, num);
                ret = meth->bytes(buf, num);
                goto err;
                }

        num *= 8; /* bytes to bits */

        if (p_UBSEC_rng_ioctl(fd,
                              UBSEC_RNG_DIRECT,
                              buf,
                              &num) != 0)
                {
                /* Hardware's a no go, failover to software */
                const RAND_METHOD *meth;

                ENGINEerr(UBSEC_F_UBSEC_RNG_BYTES, UBSEC_R_REQUEST_FAILED);
                p_UBSEC_ubsec_close(fd);

                num = p_UBSEC_ubsec_bits_to_bytes(num);
                meth = RAND_SSLeay();
                meth->seed(buf, num);
                ret = meth->bytes(buf, num);

                goto err;
                }

        p_UBSEC_ubsec_close(fd);

        ret = 1;
err:
        return(ret);
        }


static int ubsec_rand_status(void)
        {
        return 0;
        }
#endif

/* This stuff is needed if this ENGINE is being compiled into a self-contained
 * shared-library. */
#ifndef OPENSSL_NO_DYNAMIC_ENGINE
static int bind_fn(ENGINE *e, const char *id)
        {
        if(id && (strcmp(id, engine_ubsec_id) != 0))
                return 0;
        if(!bind_helper(e))
                return 0;
        return 1;
        }
IMPLEMENT_DYNAMIC_CHECK_FN()
IMPLEMENT_DYNAMIC_BIND_FN(bind_fn)
#endif /* OPENSSL_NO_DYNAMIC_ENGINE */

#endif /* !OPENSSL_NO_HW_UBSEC */
#endif /* !OPENSSL_NO_HW */