/**********************************************************************

 *                          gost_eng.c                                *

 *             Copyright (c) 2005-2006 Cryptocom LTD                  *

 *         This file is distributed under the same license as OpenSSL *

 *                                                                    *

 *              Main file of GOST engine                              *

 *       for OpenSSL                                                  *

 *          Requires OpenSSL 0.9.9 for compilation                    *

 **********************************************************************/

#include <string.h>

#include <openssl/crypto.h>

#include <openssl/err.h>

#include <openssl/evp.h>

#include <openssl/engine.h>

#include <openssl/obj_mac.h>

#include "e_gost_err.h"

#include "gost_lcl.h"

static const char *engine_gost_id = "gost";

static const char *engine_gost_name =

    "Reference implementation of GOST engine";

/* Symmetric cipher and digest function registrar */

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

                        const int **nids, int nid);

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

                        const int **nids, int ind);

static int gost_pkey_meths(ENGINE *e, EVP_PKEY_METHOD **pmeth,

                           const int **nids, int nid);

static int gost_pkey_asn1_meths(ENGINE *e, EVP_PKEY_ASN1_METHOD **ameth,

                                const int **nids, int nid);

static int gost_cipher_nids[] = { NID_id_Gost28147_89, NID_gost89_cnt, 0 };

static int gost_digest_nids[] =

    { NID_id_GostR3411_94, NID_id_Gost28147_89_MAC, 0 };

static int gost_pkey_meth_nids[] = { NID_id_GostR3410_94,

    NID_id_GostR3410_2001, NID_id_Gost28147_89_MAC, 0

};

static EVP_PKEY_METHOD *pmeth_GostR3410_94 = NULL,

    *pmeth_GostR3410_2001 = NULL, *pmeth_Gost28147_MAC = NULL;

static EVP_PKEY_ASN1_METHOD *ameth_GostR3410_94 = NULL,

    *ameth_GostR3410_2001 = NULL, *ameth_Gost28147_MAC = NULL;

static int gost_engine_init(ENGINE *e)

{

    return 1;

}

static int gost_engine_finish(ENGINE *e)

{

    return 1;

}

static int gost_engine_destroy(ENGINE *e)

{

    gost_param_free();

    pmeth_GostR3410_94 = NULL;

    pmeth_GostR3410_2001 = NULL;

    pmeth_Gost28147_MAC = NULL;

    ameth_GostR3410_94 = NULL;

    ameth_GostR3410_2001 = NULL;

    ameth_Gost28147_MAC = NULL;

    return 1;

}

static int bind_gost(ENGINE *e, const char *id)

{

    int ret = 0;

    if (id && strcmp(id, engine_gost_id))

        return 0;

    if (ameth_GostR3410_94) {

        printf("GOST engine already loaded\n");

        goto end;

    }

    if (!ENGINE_set_id(e, engine_gost_id)) {

        printf("ENGINE_set_id failed\n");

        goto end;

    }

    if (!ENGINE_set_name(e, engine_gost_name)) {

        printf("ENGINE_set_name failed\n");

        goto end;

    }

    if (!ENGINE_set_digests(e, gost_digests)) {

        printf("ENGINE_set_digests failed\n");

        goto end;

    }

    if (!ENGINE_set_ciphers(e, gost_ciphers)) {

        printf("ENGINE_set_ciphers failed\n");

        goto end;

    }

    if (!ENGINE_set_pkey_meths(e, gost_pkey_meths)) {

        printf("ENGINE_set_pkey_meths failed\n");

        goto end;

    }

    if (!ENGINE_set_pkey_asn1_meths(e, gost_pkey_asn1_meths)) {

        printf("ENGINE_set_pkey_asn1_meths failed\n");

        goto end;

    }

    /* Control function and commands */

    if (!ENGINE_set_cmd_defns(e, gost_cmds)) {

        fprintf(stderr, "ENGINE_set_cmd_defns failed\n");

        goto end;

    }

    if (!ENGINE_set_ctrl_function(e, gost_control_func)) {

        fprintf(stderr, "ENGINE_set_ctrl_func failed\n");

        goto end;

    }

    if (!ENGINE_set_destroy_function(e, gost_engine_destroy)

        || !ENGINE_set_init_function(e, gost_engine_init)

        || !ENGINE_set_finish_function(e, gost_engine_finish)) {

        goto end;

    }

    if (!register_ameth_gost

        (NID_id_GostR3410_94, &ameth_GostR3410_94, "GOST94",

         "GOST R 34.10-94"))

        goto end;

    if (!register_ameth_gost

        (NID_id_GostR3410_2001, &ameth_GostR3410_2001, "GOST2001",

         "GOST R 34.10-2001"))

        goto end;

    if (!register_ameth_gost(NID_id_Gost28147_89_MAC, &ameth_Gost28147_MAC,

                             "GOST-MAC", "GOST 28147-89 MAC"))

        goto end;

    if (!register_pmeth_gost(NID_id_GostR3410_94, &pmeth_GostR3410_94, 0))

        goto end;

    if (!register_pmeth_gost(NID_id_GostR3410_2001, &pmeth_GostR3410_2001, 0))

        goto end;

    if (!register_pmeth_gost

        (NID_id_Gost28147_89_MAC, &pmeth_Gost28147_MAC, 0))

        goto end;

    if (!ENGINE_register_ciphers(e)

        || !ENGINE_register_digests(e)

        || !ENGINE_register_pkey_meths(e)

        /* These two actually should go in LIST_ADD command */

        || !EVP_add_cipher(&cipher_gost)

        || !EVP_add_cipher(&cipher_gost_cpacnt)

        || !EVP_add_digest(&digest_gost)

        || !EVP_add_digest(&imit_gost_cpa)

        ) {

        goto end;

    }

    ERR_load_GOST_strings();

    ret = 1;

 end:

    return ret;

}

#ifndef OPENSSL_NO_DYNAMIC_ENGINE

IMPLEMENT_DYNAMIC_BIND_FN(bind_gost)

    IMPLEMENT_DYNAMIC_CHECK_FN()

#endif                          /* ndef OPENSSL_NO_DYNAMIC_ENGINE */

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

                        const int **nids, int nid)

{

    int ok = 1;

    if (!digest) {

        *nids = gost_digest_nids;

        return 2;

    }

    /*

     * printf("Digest no %d requested\n",nid);

     */

    if (nid == NID_id_GostR3411_94) {

        *digest = &digest_gost;

    } else if (nid == NID_id_Gost28147_89_MAC) {

        *digest = &imit_gost_cpa;

    } else {

        ok = 0;

        *digest = NULL;

    }

    return ok;

}

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

                        const int **nids, int nid)

{

    int ok = 1;

    if (!cipher) {

        *nids = gost_cipher_nids;

        return 2;               /* two ciphers are supported */

    }

    if (nid == NID_id_Gost28147_89) {

        *cipher = &cipher_gost;

    } else if (nid == NID_gost89_cnt) {

        *cipher = &cipher_gost_cpacnt;

    } else {

        ok = 0;

        *cipher = NULL;

    }

    return ok;

}

static int gost_pkey_meths(ENGINE *e, EVP_PKEY_METHOD **pmeth,

                           const int **nids, int nid)

{

    if (!pmeth) {

        *nids = gost_pkey_meth_nids;

        return 3;

    }

    switch (nid) {

    case NID_id_GostR3410_94:

        *pmeth = pmeth_GostR3410_94;

        return 1;

    case NID_id_GostR3410_2001:

        *pmeth = pmeth_GostR3410_2001;

        return 1;

    case NID_id_Gost28147_89_MAC:

        *pmeth = pmeth_Gost28147_MAC;

        return 1;

    default:;

    }

    *pmeth = NULL;

    return 0;

}

static int gost_pkey_asn1_meths(ENGINE *e, EVP_PKEY_ASN1_METHOD **ameth,

                                const int **nids, int nid)

{

    if (!ameth) {

        *nids = gost_pkey_meth_nids;

        return 3;

    }

    switch (nid) {

    case NID_id_GostR3410_94:

        *ameth = ameth_GostR3410_94;

        return 1;

    case NID_id_GostR3410_2001:

        *ameth = ameth_GostR3410_2001;

        return 1;

    case NID_id_Gost28147_89_MAC:

        *ameth = ameth_Gost28147_MAC;

        return 1;

    default:;

    }

    *ameth = NULL;

    return 0;

}

#ifdef OPENSSL_NO_DYNAMIC_ENGINE

static ENGINE *engine_gost(void)

{

    ENGINE *ret = ENGINE_new();

    if (!ret)

        return NULL;

    if (!bind_gost(ret, engine_gost_id)) {

        ENGINE_free(ret);

        return NULL;

    }

    return ret;

}

void ENGINE_load_gost(void)

{

    ENGINE *toadd;

    if (pmeth_GostR3410_94)

        return;

    toadd = engine_gost();

    if (!toadd)

        return;

    ENGINE_add(toadd);

    ENGINE_free(toadd);

    ERR_clear_error();

}

#endif