/*

 * Copyright 2006-2023 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the Apache License 2.0 (the "License").  You may not use

 * this file except in compliance with the License.  You can obtain a copy

 * in the file LICENSE in the source distribution or at

 * https://www.openssl.org/source/license.html

 */

#include <stdio.h>

#include <stdlib.h>

#include <openssl/core.h>

#include <openssl/core_names.h>

#include "internal/cryptlib.h"

#include "internal/core.h"

#include <openssl/objects.h>

#include <openssl/evp.h>

#include "crypto/bn.h"

#ifndef FIPS_MODULE

# include "crypto/asn1.h"

#endif

#include "crypto/evp.h"

#include "evp_local.h"

static int gen_init(EVP_PKEY_CTX *ctx, int operation)

{

    int ret = 0;

    if (ctx == NULL)

        goto not_supported;

    evp_pkey_ctx_free_old_ops(ctx);

    ctx->operation = operation;

    if (ctx->keymgmt == NULL || ctx->keymgmt->gen_init == NULL)

        goto legacy;

    switch (operation) {

    case EVP_PKEY_OP_PARAMGEN:

        ctx->op.keymgmt.genctx =

            evp_keymgmt_gen_init(ctx->keymgmt,

                                 OSSL_KEYMGMT_SELECT_ALL_PARAMETERS, NULL);

        break;

    case EVP_PKEY_OP_KEYGEN:

        ctx->op.keymgmt.genctx =

            evp_keymgmt_gen_init(ctx->keymgmt, OSSL_KEYMGMT_SELECT_KEYPAIR,

                                 NULL);

        break;

    }

    if (ctx->op.keymgmt.genctx == NULL)

        ERR_raise(ERR_LIB_EVP, EVP_R_INITIALIZATION_ERROR);

    else

        ret = 1;

    goto end;

 legacy:

#ifdef FIPS_MODULE

    goto not_supported;

#else

    if (ctx->pmeth == NULL

        || (operation == EVP_PKEY_OP_PARAMGEN

            && ctx->pmeth->paramgen == NULL)

        || (operation == EVP_PKEY_OP_KEYGEN

            && ctx->pmeth->keygen == NULL))

        goto not_supported;

    ret = 1;

    switch (operation) {

    case EVP_PKEY_OP_PARAMGEN:

        if (ctx->pmeth->paramgen_init != NULL)

            ret = ctx->pmeth->paramgen_init(ctx);

        break;

    case EVP_PKEY_OP_KEYGEN:

        if (ctx->pmeth->keygen_init != NULL)

            ret = ctx->pmeth->keygen_init(ctx);

        break;

    }

#endif

 end:

    if (ret <= 0 && ctx != NULL) {

        evp_pkey_ctx_free_old_ops(ctx);

        ctx->operation = EVP_PKEY_OP_UNDEFINED;

    }

    return ret;

 not_supported:

    ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);

    ret = -2;

    goto end;

}

int EVP_PKEY_paramgen_init(EVP_PKEY_CTX *ctx)

{

    return gen_init(ctx, EVP_PKEY_OP_PARAMGEN);

}

int EVP_PKEY_keygen_init(EVP_PKEY_CTX *ctx)

{

    return gen_init(ctx, EVP_PKEY_OP_KEYGEN);

}

static int ossl_callback_to_pkey_gencb(const OSSL_PARAM params[], void *arg)

{

    EVP_PKEY_CTX *ctx = arg;

    const OSSL_PARAM *param = NULL;

    int p = -1, n = -1;

    if (ctx->pkey_gencb == NULL)

        return 1;                /* No callback?  That's fine */

    if ((param = OSSL_PARAM_locate_const(params, OSSL_GEN_PARAM_POTENTIAL))

        == NULL

        || !OSSL_PARAM_get_int(param, &p))

        return 0;

    if ((param = OSSL_PARAM_locate_const(params, OSSL_GEN_PARAM_ITERATION))

        == NULL

        || !OSSL_PARAM_get_int(param, &n))

        return 0;

    ctx->keygen_info[0] = p;

    ctx->keygen_info[1] = n;

    return ctx->pkey_gencb(ctx);

}

int EVP_PKEY_generate(EVP_PKEY_CTX *ctx, EVP_PKEY **ppkey)

{

    int ret = 0;

    EVP_PKEY *allocated_pkey = NULL;

    /* Legacy compatible keygen callback info, only used with provider impls */

    int gentmp[2];

    if (ppkey == NULL)

        return -1;

    if (ctx == NULL)

        goto not_supported;

    if ((ctx->operation & EVP_PKEY_OP_TYPE_GEN) == 0)

        goto not_initialized;

    if (*ppkey == NULL)

        *ppkey = allocated_pkey = EVP_PKEY_new();

    if (*ppkey == NULL) {

        ERR_raise(ERR_LIB_EVP, ERR_R_EVP_LIB);

        return -1;

    }

    if (ctx->op.keymgmt.genctx == NULL)

        goto legacy;

    /*

     * Assigning gentmp to ctx->keygen_info is something our legacy

     * implementations do.  Because the provider implementations aren't

     * allowed to reach into our EVP_PKEY_CTX, we need to provide similar

     * space for backward compatibility.  It's ok that we attach a local

     * variable, as it should only be useful in the calls down from here.

     * This is cleared as soon as it isn't useful any more, i.e. directly

     * after the evp_keymgmt_util_gen() call.

     */

    ctx->keygen_info = gentmp;

    ctx->keygen_info_count = 2;

    ret = 1;

    if (ctx->pkey != NULL) {

        EVP_KEYMGMT *tmp_keymgmt = ctx->keymgmt;

        void *keydata =

            evp_pkey_export_to_provider(ctx->pkey, ctx->libctx,

                                        &tmp_keymgmt, ctx->propquery);

        if (tmp_keymgmt == NULL)

            goto not_supported;

        /*

         * It's ok if keydata is NULL here.  The backend is expected to deal

         * with that as it sees fit.

         */

        ret = evp_keymgmt_gen_set_template(ctx->keymgmt,

                                           ctx->op.keymgmt.genctx, keydata);

    }

    /*

     * the returned value from evp_keymgmt_util_gen() is cached in *ppkey,

     * so we do not need to save it, just check it.

     */

    ret = ret

        && (evp_keymgmt_util_gen(*ppkey, ctx->keymgmt, ctx->op.keymgmt.genctx,

                                 ossl_callback_to_pkey_gencb, ctx)

            != NULL);

    ctx->keygen_info = NULL;

#ifndef FIPS_MODULE

    /* In case |*ppkey| was originally a legacy key */

    if (ret)

        evp_pkey_free_legacy(*ppkey);

#endif

    /*

     * Because we still have legacy keys

     */

    (*ppkey)->type = ctx->legacy_keytype;

    goto end;

 legacy:

#ifdef FIPS_MODULE

    goto not_supported;

#else

    /*

     * If we get here then we're using legacy paramgen/keygen. In that case

     * the pkey in ctx (if there is one) had better not be provided (because the

     * legacy methods may not know how to handle it). However we can only get

     * here if ctx->op.keymgmt.genctx == NULL, but that should never be the case

     * if ctx->pkey is provided because we don't allow this when we initialise

     * the ctx.

     */

    if (ctx->pkey != NULL && !ossl_assert(!evp_pkey_is_provided(ctx->pkey)))

        goto not_accessible;

    switch (ctx->operation) {

    case EVP_PKEY_OP_PARAMGEN:

        ret = ctx->pmeth->paramgen(ctx, *ppkey);

        break;

    case EVP_PKEY_OP_KEYGEN:

        ret = ctx->pmeth->keygen(ctx, *ppkey);

        break;

    default:

        goto not_supported;

    }

#endif

 end:

    if (ret <= 0) {

        if (allocated_pkey != NULL)

            *ppkey = NULL;

        EVP_PKEY_free(allocated_pkey);

    }

    return ret;

 not_supported:

    ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);

    ret = -2;

    goto end;

 not_initialized:

    ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_INITIALIZED);

    ret = -1;

    goto end;

#ifndef FIPS_MODULE

 not_accessible:

    ERR_raise(ERR_LIB_EVP, EVP_R_INACCESSIBLE_DOMAIN_PARAMETERS);

    ret = -1;

    goto end;

#endif

}

int EVP_PKEY_paramgen(EVP_PKEY_CTX *ctx, EVP_PKEY **ppkey)

{

    if (ctx->operation != EVP_PKEY_OP_PARAMGEN) {

        ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_INITIALIZED);

        return -1;

    }

    return EVP_PKEY_generate(ctx, ppkey);

}

int EVP_PKEY_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY **ppkey)

{

    if (ctx->operation != EVP_PKEY_OP_KEYGEN) {

        ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_INITIALIZED);

        return -1;

    }

    return EVP_PKEY_generate(ctx, ppkey);

}

void EVP_PKEY_CTX_set_cb(EVP_PKEY_CTX *ctx, EVP_PKEY_gen_cb *cb)

{

    ctx->pkey_gencb = cb;

}

EVP_PKEY_gen_cb *EVP_PKEY_CTX_get_cb(EVP_PKEY_CTX *ctx)

{

    return ctx->pkey_gencb;

}

/*

 * "translation callback" to call EVP_PKEY_CTX callbacks using BN_GENCB style

 * callbacks.

 */

static int trans_cb(int a, int b, BN_GENCB *gcb)

{

    EVP_PKEY_CTX *ctx = BN_GENCB_get_arg(gcb);

    ctx->keygen_info[0] = a;

    ctx->keygen_info[1] = b;

    return ctx->pkey_gencb(ctx);

}

void evp_pkey_set_cb_translate(BN_GENCB *cb, EVP_PKEY_CTX *ctx)

{

    BN_GENCB_set(cb, trans_cb, ctx);

}

int EVP_PKEY_CTX_get_keygen_info(EVP_PKEY_CTX *ctx, int idx)

{

    if (idx == -1)

        return ctx->keygen_info_count;

    if (idx < 0 || idx > ctx->keygen_info_count)

        return 0;

    return ctx->keygen_info[idx];

}

#ifndef FIPS_MODULE

EVP_PKEY *EVP_PKEY_new_mac_key(int type, ENGINE *e,

                               const unsigned char *key, int keylen)

{

    EVP_PKEY_CTX *mac_ctx = NULL;

    EVP_PKEY *mac_key = NULL;

    mac_ctx = EVP_PKEY_CTX_new_id(type, e);

    if (!mac_ctx)

        return NULL;

    if (EVP_PKEY_keygen_init(mac_ctx) <= 0)

        goto merr;

    if (EVP_PKEY_CTX_set_mac_key(mac_ctx, key, keylen) <= 0)

        goto merr;

    if (EVP_PKEY_keygen(mac_ctx, &mac_key) <= 0)

        goto merr;

 merr:

    EVP_PKEY_CTX_free(mac_ctx);

    return mac_key;

}

#endif /* FIPS_MODULE */

/*- All methods below can also be used in FIPS_MODULE */

static int fromdata_init(EVP_PKEY_CTX *ctx, int operation)

{

    if (ctx == NULL || ctx->keytype == NULL)

        goto not_supported;

    evp_pkey_ctx_free_old_ops(ctx);

    if (ctx->keymgmt == NULL)

        goto not_supported;

    ctx->operation = operation;

    return 1;

 not_supported:

    if (ctx != NULL)

        ctx->operation = EVP_PKEY_OP_UNDEFINED;

    ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);

    return -2;

}

int EVP_PKEY_fromdata_init(EVP_PKEY_CTX *ctx)

{

    return fromdata_init(ctx, EVP_PKEY_OP_FROMDATA);

}

int EVP_PKEY_fromdata(EVP_PKEY_CTX *ctx, EVP_PKEY **ppkey, int selection,

                      OSSL_PARAM params[])

{

    void *keydata = NULL;

    EVP_PKEY *allocated_pkey = NULL;

    if (ctx == NULL || (ctx->operation & EVP_PKEY_OP_FROMDATA) == 0) {

        ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);

        return -2;

    }

    if (ppkey == NULL)

        return -1;

    if (*ppkey == NULL)

        allocated_pkey = *ppkey = EVP_PKEY_new();

    if (*ppkey == NULL) {

        ERR_raise(ERR_LIB_EVP, ERR_R_EVP_LIB);

        return -1;

    }

    keydata = evp_keymgmt_util_fromdata(*ppkey, ctx->keymgmt, selection, params);

    if (keydata == NULL) {

        if (allocated_pkey != NULL) {

            *ppkey = NULL;

            EVP_PKEY_free(allocated_pkey);

        }

        return 0;

    }

    /* keydata is cached in *ppkey, so we need not bother with it further */

    return 1;

}

const OSSL_PARAM *EVP_PKEY_fromdata_settable(EVP_PKEY_CTX *ctx, int selection)

{

    /* We call fromdata_init to get ctx->keymgmt populated */

    if (fromdata_init(ctx, EVP_PKEY_OP_UNDEFINED) == 1)

        return evp_keymgmt_import_types(ctx->keymgmt, selection);

    return NULL;

}

static OSSL_CALLBACK ossl_pkey_todata_cb;

static int ossl_pkey_todata_cb(const OSSL_PARAM params[], void *arg)

{

    OSSL_PARAM **ret = arg;

    *ret = OSSL_PARAM_dup(params);

    return 1;

}

int EVP_PKEY_todata(const EVP_PKEY *pkey, int selection, OSSL_PARAM **params)

{

    if (params == NULL)

        return 0;

    return EVP_PKEY_export(pkey, selection, ossl_pkey_todata_cb, params);

}

#ifndef FIPS_MODULE

struct fake_import_data_st {

    OSSL_CALLBACK *export_cb;

    void *export_cbarg;

};

static OSSL_FUNC_keymgmt_import_fn pkey_fake_import;

static int pkey_fake_import(void *fake_keydata, int ignored_selection,

                            const OSSL_PARAM params[])

{

    struct fake_import_data_st *data = fake_keydata;

    return data->export_cb(params, data->export_cbarg);

}

#endif

int EVP_PKEY_export(const EVP_PKEY *pkey, int selection,

                    OSSL_CALLBACK *export_cb, void *export_cbarg)

{

    if (pkey == NULL) {

        ERR_raise(ERR_LIB_EVP, ERR_R_PASSED_NULL_PARAMETER);

        return 0;

    }

#ifndef FIPS_MODULE

    if (evp_pkey_is_legacy(pkey)) {

        struct fake_import_data_st data;

        data.export_cb = export_cb;

        data.export_cbarg = export_cbarg;

        /*

         * We don't need to care about libctx or propq here, as we're only

         * interested in the resulting OSSL_PARAM array.

         */

        return pkey->ameth->export_to(pkey, &data, pkey_fake_import,

                                      NULL, NULL);

    }

#endif

    return evp_keymgmt_util_export(pkey, selection, export_cb, export_cbarg);

}