/*

 * Copyright 2018-2021 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 <string.h>

#include <stdarg.h>

#include <openssl/evp.h>

#include <openssl/err.h>

#include <openssl/core.h>

#include <openssl/core_names.h>

#include <openssl/types.h>

#include "internal/nelem.h"

#include "crypto/evp.h"

#include "internal/provider.h"

#include "evp_local.h"

EVP_MAC_CTX *EVP_MAC_CTX_new(EVP_MAC *mac)

{

    EVP_MAC_CTX *ctx = OPENSSL_zalloc(sizeof(EVP_MAC_CTX));

    if (ctx != NULL) {

        ctx->meth = mac;

        if ((ctx->algctx = mac->newctx(ossl_provider_ctx(mac->prov))) == NULL

            || !EVP_MAC_up_ref(mac)) {

            mac->freectx(ctx->algctx);

            ERR_raise(ERR_LIB_EVP, ERR_R_EVP_LIB);

            OPENSSL_free(ctx);

            ctx = NULL;

        }

    }

    return ctx;

}

void EVP_MAC_CTX_free(EVP_MAC_CTX *ctx)

{

    if (ctx == NULL)

        return;

    ctx->meth->freectx(ctx->algctx);

    ctx->algctx = NULL;

    /* refcnt-- */

    EVP_MAC_free(ctx->meth);

    OPENSSL_free(ctx);

}

EVP_MAC_CTX *EVP_MAC_CTX_dup(const EVP_MAC_CTX *src)

{

    EVP_MAC_CTX *dst;

    if (src->algctx == NULL)

        return NULL;

    dst = OPENSSL_malloc(sizeof(*dst));

    if (dst == NULL)

        return NULL;

    *dst = *src;

    if (!EVP_MAC_up_ref(dst->meth)) {

        ERR_raise(ERR_LIB_EVP, ERR_R_EVP_LIB);

        OPENSSL_free(dst);

        return NULL;

    }

    dst->algctx = src->meth->dupctx(src->algctx);

    if (dst->algctx == NULL) {

        EVP_MAC_CTX_free(dst);

        return NULL;

    }

    return dst;

}

EVP_MAC *EVP_MAC_CTX_get0_mac(EVP_MAC_CTX *ctx)

{

    return ctx->meth;

}

static size_t get_size_t_ctx_param(EVP_MAC_CTX *ctx, const char *name)

{

    size_t sz = 0;

    if (ctx->algctx != NULL) {

        OSSL_PARAM params[2] = { OSSL_PARAM_END, OSSL_PARAM_END };

        params[0] = OSSL_PARAM_construct_size_t(name, &sz);

        if (ctx->meth->get_ctx_params != NULL) {

            if (ctx->meth->get_ctx_params(ctx->algctx, params))

                return sz;

        } else if (ctx->meth->get_params != NULL) {

            if (ctx->meth->get_params(params))

                return sz;

        }

    }

    /*

     * If the MAC hasn't been initialized yet, or there is no size to get,

     * we return zero

     */

    return 0;

}

size_t EVP_MAC_CTX_get_mac_size(EVP_MAC_CTX *ctx)

{

    return get_size_t_ctx_param(ctx, OSSL_MAC_PARAM_SIZE);

}

size_t EVP_MAC_CTX_get_block_size(EVP_MAC_CTX *ctx)

{

    return get_size_t_ctx_param(ctx, OSSL_MAC_PARAM_BLOCK_SIZE);

}

int EVP_MAC_init(EVP_MAC_CTX *ctx, const unsigned char *key, size_t keylen,

                 const OSSL_PARAM params[])

{

    return ctx->meth->init(ctx->algctx, key, keylen, params);

}

int EVP_MAC_update(EVP_MAC_CTX *ctx, const unsigned char *data, size_t datalen)

{

    return ctx->meth->update(ctx->algctx, data, datalen);

}

static int evp_mac_final(EVP_MAC_CTX *ctx, int xof,

                         unsigned char *out, size_t *outl, size_t outsize)

{

    size_t l;

    int res;

    OSSL_PARAM params[2];

    size_t macsize;

    if (ctx == NULL || ctx->meth == NULL) {

        ERR_raise(ERR_LIB_EVP, EVP_R_INVALID_NULL_ALGORITHM);

        return 0;

    }

    if (ctx->meth->final == NULL) {

        ERR_raise(ERR_LIB_EVP, EVP_R_FINAL_ERROR);

        return 0;

    }

    macsize = EVP_MAC_CTX_get_mac_size(ctx);

    if (out == NULL) {

        if (outl == NULL) {

            ERR_raise(ERR_LIB_EVP, ERR_R_PASSED_NULL_PARAMETER);

            return 0;

        }

        *outl = macsize;

        return 1;

    }

    if (outsize < macsize) {

        ERR_raise(ERR_LIB_EVP, EVP_R_BUFFER_TOO_SMALL);

        return 0;

    }

    if (xof) {

        params[0] = OSSL_PARAM_construct_int(OSSL_MAC_PARAM_XOF, &xof);

        params[1] = OSSL_PARAM_construct_end();

        if (EVP_MAC_CTX_set_params(ctx, params) <= 0) {

            ERR_raise(ERR_LIB_EVP, EVP_R_SETTING_XOF_FAILED);

            return 0;

        }

    }

    res = ctx->meth->final(ctx->algctx, out, &l, outsize);

    if (outl != NULL)

        *outl = l;

    return res;

}

int EVP_MAC_final(EVP_MAC_CTX *ctx,

                  unsigned char *out, size_t *outl, size_t outsize)

{

    return evp_mac_final(ctx, 0, out, outl, outsize);

}

int EVP_MAC_finalXOF(EVP_MAC_CTX *ctx, unsigned char *out, size_t outsize)

{

    return evp_mac_final(ctx, 1, out, NULL, outsize);

}

/*

 * The {get,set}_params functions return 1 if there is no corresponding

 * function in the implementation.  This is the same as if there was one,

 * but it didn't recognise any of the given params, i.e. nothing in the

 * bag of parameters was useful.

 */

int EVP_MAC_get_params(EVP_MAC *mac, OSSL_PARAM params[])

{

    if (mac->get_params != NULL)

        return mac->get_params(params);

    return 1;

}

int EVP_MAC_CTX_get_params(EVP_MAC_CTX *ctx, OSSL_PARAM params[])

{

    if (ctx->meth->get_ctx_params != NULL)

        return ctx->meth->get_ctx_params(ctx->algctx, params);

    return 1;

}

int EVP_MAC_CTX_set_params(EVP_MAC_CTX *ctx, const OSSL_PARAM params[])

{

    if (ctx->meth->set_ctx_params != NULL)

        return ctx->meth->set_ctx_params(ctx->algctx, params);

    return 1;

}

int evp_mac_get_number(const EVP_MAC *mac)

{

    return mac->name_id;

}

const char *EVP_MAC_get0_name(const EVP_MAC *mac)

{

    return mac->type_name;

}

const char *EVP_MAC_get0_description(const EVP_MAC *mac)

{

    return mac->description;

}

int EVP_MAC_is_a(const EVP_MAC *mac, const char *name)

{

    return mac != NULL && evp_is_a(mac->prov, mac->name_id, NULL, name);

}

int EVP_MAC_names_do_all(const EVP_MAC *mac,

                         void (*fn)(const char *name, void *data),

                         void *data)

{

    if (mac->prov != NULL)

        return evp_names_do_all(mac->prov, mac->name_id, fn, data);

    return 1;

}

unsigned char *EVP_Q_mac(OSSL_LIB_CTX *libctx,

                         const char *name, const char *propq,

                         const char *subalg, const OSSL_PARAM *params,

                         const void *key, size_t keylen,

                         const unsigned char *data, size_t datalen,

                         unsigned char *out, size_t outsize, size_t *outlen)

{

    EVP_MAC *mac = EVP_MAC_fetch(libctx, name, propq);

    OSSL_PARAM subalg_param[] = { OSSL_PARAM_END, OSSL_PARAM_END };

    EVP_MAC_CTX *ctx  = NULL;

    size_t len = 0;

    unsigned char *res = NULL;

    if (outlen != NULL)

        *outlen = 0;

    if (mac == NULL)

        return NULL;

    if (subalg != NULL) {

        const OSSL_PARAM *defined_params = EVP_MAC_settable_ctx_params(mac);

        const char *param_name = OSSL_MAC_PARAM_DIGEST;

        /*

         * The underlying algorithm may be a cipher or a digest.

         * We don't know which it is, but we can ask the MAC what it

         * should be and bet on that.

         */

        if (OSSL_PARAM_locate_const(defined_params, param_name) == NULL) {

            param_name = OSSL_MAC_PARAM_CIPHER;

            if (OSSL_PARAM_locate_const(defined_params, param_name) == NULL) {

                ERR_raise(ERR_LIB_EVP, ERR_R_PASSED_INVALID_ARGUMENT);

                goto err;

            }

        }

        subalg_param[0] =

            OSSL_PARAM_construct_utf8_string(param_name, (char *)subalg, 0);

    }

    /* Single-shot - on NULL key input, set dummy key value for EVP_MAC_Init. */

    if (key == NULL && keylen == 0)

        key = data;

    if ((ctx = EVP_MAC_CTX_new(mac)) != NULL

            && EVP_MAC_CTX_set_params(ctx, subalg_param)

            && EVP_MAC_CTX_set_params(ctx, params)

            && EVP_MAC_init(ctx, key, keylen, params)

            && EVP_MAC_update(ctx, data, datalen)

            && EVP_MAC_final(ctx, out, &len, outsize)) {

        if (out == NULL) {

            out = OPENSSL_malloc(len);

            if (out != NULL && !EVP_MAC_final(ctx, out, NULL, len)) {

                OPENSSL_free(out);

                out = NULL;

            }

        }

        res = out;

        if (res != NULL && outlen != NULL)

            *outlen = len;

    }

 err:

    EVP_MAC_CTX_free(ctx);

    EVP_MAC_free(mac);

    return res;

}