/*

 * Copyright 2019-2025 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 <openssl/evp.h>

#include <openssl/err.h>

#include <openssl/core.h>

#include <openssl/core_dispatch.h>

#include <openssl/kdf.h>

#include "internal/provider.h"

#include "internal/core.h"

#include "crypto/evp.h"

#include "evp_local.h"

static int evp_kdf_up_ref(void *vkdf)

{

    EVP_KDF *kdf = (EVP_KDF *)vkdf;

    int ref = 0;

    CRYPTO_UP_REF(&kdf->refcnt, &ref);

    return 1;

}

static void evp_kdf_free(void *vkdf)

{

    EVP_KDF *kdf = (EVP_KDF *)vkdf;

    int ref = 0;

    if (kdf == NULL)

        return;

    CRYPTO_DOWN_REF(&kdf->refcnt, &ref);

    if (ref > 0)

        return;

    OPENSSL_free(kdf->type_name);

    ossl_provider_free(kdf->prov);

    CRYPTO_FREE_REF(&kdf->refcnt);

    OPENSSL_free(kdf);

}

static void *evp_kdf_new(void)

{

    EVP_KDF *kdf = NULL;

    if ((kdf = OPENSSL_zalloc(sizeof(*kdf))) == NULL

        || !CRYPTO_NEW_REF(&kdf->refcnt, 1)) {

        OPENSSL_free(kdf);

        return NULL;

    }

    return kdf;

}

static void *evp_kdf_from_algorithm(int name_id,

                                    const OSSL_ALGORITHM *algodef,

                                    OSSL_PROVIDER *prov)

{

    const OSSL_DISPATCH *fns = algodef->implementation;

    EVP_KDF *kdf = NULL;

    int fnkdfcnt = 0, fnctxcnt = 0;

    if ((kdf = evp_kdf_new()) == NULL) {

        ERR_raise(ERR_LIB_EVP, ERR_R_EVP_LIB);

        return NULL;

    }

    kdf->name_id = name_id;

    if ((kdf->type_name = ossl_algorithm_get1_first_name(algodef)) == NULL)

        goto err;

    kdf->description = algodef->algorithm_description;

    for (; fns->function_id != 0; fns++) {

        switch (fns->function_id) {

        case OSSL_FUNC_KDF_NEWCTX:

            if (kdf->newctx != NULL)

                break;

            kdf->newctx = OSSL_FUNC_kdf_newctx(fns);

            fnctxcnt++;

            break;

        case OSSL_FUNC_KDF_DUPCTX:

            if (kdf->dupctx != NULL)

                break;

            kdf->dupctx = OSSL_FUNC_kdf_dupctx(fns);

            break;

        case OSSL_FUNC_KDF_FREECTX:

            if (kdf->freectx != NULL)

                break;

            kdf->freectx = OSSL_FUNC_kdf_freectx(fns);

            fnctxcnt++;

            break;

        case OSSL_FUNC_KDF_RESET:

            if (kdf->reset != NULL)

                break;

            kdf->reset = OSSL_FUNC_kdf_reset(fns);

            break;

        case OSSL_FUNC_KDF_DERIVE:

            if (kdf->derive != NULL)

                break;

            kdf->derive = OSSL_FUNC_kdf_derive(fns);

            fnkdfcnt++;

            break;

        case OSSL_FUNC_KDF_GETTABLE_PARAMS:

            if (kdf->gettable_params != NULL)

                break;

            kdf->gettable_params =

                OSSL_FUNC_kdf_gettable_params(fns);

            break;

        case OSSL_FUNC_KDF_GETTABLE_CTX_PARAMS:

            if (kdf->gettable_ctx_params != NULL)

                break;

            kdf->gettable_ctx_params =

                OSSL_FUNC_kdf_gettable_ctx_params(fns);

            break;

        case OSSL_FUNC_KDF_SETTABLE_CTX_PARAMS:

            if (kdf->settable_ctx_params != NULL)

                break;

            kdf->settable_ctx_params =

                OSSL_FUNC_kdf_settable_ctx_params(fns);

            break;

        case OSSL_FUNC_KDF_GET_PARAMS:

            if (kdf->get_params != NULL)

                break;

            kdf->get_params = OSSL_FUNC_kdf_get_params(fns);

            break;

        case OSSL_FUNC_KDF_GET_CTX_PARAMS:

            if (kdf->get_ctx_params != NULL)

                break;

            kdf->get_ctx_params = OSSL_FUNC_kdf_get_ctx_params(fns);

            break;

        case OSSL_FUNC_KDF_SET_CTX_PARAMS:

            if (kdf->set_ctx_params != NULL)

                break;

            kdf->set_ctx_params = OSSL_FUNC_kdf_set_ctx_params(fns);

            break;

        case OSSL_FUNC_KDF_SET_SKEY:

            if (kdf->set_skey != NULL)

                break;

            kdf->set_skey = OSSL_FUNC_kdf_set_skey(fns);

            break;

        case OSSL_FUNC_KDF_DERIVE_SKEY:

            if (kdf->derive_skey != NULL)

                break;

            kdf->derive_skey = OSSL_FUNC_kdf_derive_skey(fns);

            break;

        }

    }

    if (fnkdfcnt != 1 || fnctxcnt != 2) {

        /*

         * In order to be a consistent set of functions we must have at least

         * a derive function, and a complete set of context management

         * functions.

         */

        ERR_raise(ERR_LIB_EVP, EVP_R_INVALID_PROVIDER_FUNCTIONS);

        goto err;

    }

    if (prov != NULL && !ossl_provider_up_ref(prov))

        goto err;

    kdf->prov = prov;

    return kdf;

err:

    evp_kdf_free(kdf);

    return NULL;

}

EVP_KDF *EVP_KDF_fetch(OSSL_LIB_CTX *libctx, const char *algorithm,

                       const char *properties)

{

    return evp_generic_fetch(libctx, OSSL_OP_KDF, algorithm, properties,

                             evp_kdf_from_algorithm, evp_kdf_up_ref,

                             evp_kdf_free);

}

int EVP_KDF_up_ref(EVP_KDF *kdf)

{

    return evp_kdf_up_ref(kdf);

}

void EVP_KDF_free(EVP_KDF *kdf)

{

    evp_kdf_free(kdf);

}

const OSSL_PARAM *EVP_KDF_gettable_params(const EVP_KDF *kdf)

{

    if (kdf->gettable_params == NULL)

        return NULL;

    return kdf->gettable_params(ossl_provider_ctx(EVP_KDF_get0_provider(kdf)));

}

const OSSL_PARAM *EVP_KDF_gettable_ctx_params(const EVP_KDF *kdf)

{

    void *alg;

    if (kdf->gettable_ctx_params == NULL)

        return NULL;

    alg = ossl_provider_ctx(EVP_KDF_get0_provider(kdf));

    return kdf->gettable_ctx_params(NULL, alg);

}

const OSSL_PARAM *EVP_KDF_settable_ctx_params(const EVP_KDF *kdf)

{

    void *alg;

    if (kdf->settable_ctx_params == NULL)

        return NULL;

    alg = ossl_provider_ctx(EVP_KDF_get0_provider(kdf));

    return kdf->settable_ctx_params(NULL, alg);

}

const OSSL_PARAM *EVP_KDF_CTX_gettable_params(EVP_KDF_CTX *ctx)

{

    void *alg;

    if (ctx->meth->gettable_ctx_params == NULL)

        return NULL;

    alg = ossl_provider_ctx(EVP_KDF_get0_provider(ctx->meth));

    return ctx->meth->gettable_ctx_params(ctx->algctx, alg);

}

const OSSL_PARAM *EVP_KDF_CTX_settable_params(EVP_KDF_CTX *ctx)

{

    void *alg;

    if (ctx->meth->settable_ctx_params == NULL)

        return NULL;

    alg = ossl_provider_ctx(EVP_KDF_get0_provider(ctx->meth));

    return ctx->meth->settable_ctx_params(ctx->algctx, alg);

}

void EVP_KDF_do_all_provided(OSSL_LIB_CTX *libctx,

                             void (*fn)(EVP_KDF *kdf, void *arg),

                             void *arg)

{

    evp_generic_do_all(libctx, OSSL_OP_KDF,

                       (void (*)(void *, void *))fn, arg,

                       evp_kdf_from_algorithm, evp_kdf_up_ref, evp_kdf_free);

}