/*

 * Copyright 2001-2021 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 "prov/ciphercommon.h"

#include "prov/ciphercommon_gcm.h"

int ossl_gcm_setiv(PROV_GCM_CTX *ctx, const unsigned char *iv, size_t ivlen)

{

    CRYPTO_gcm128_setiv(&ctx->gcm, iv, ivlen);

    return 1;

}

int ossl_gcm_aad_update(PROV_GCM_CTX *ctx, const unsigned char *aad,

    size_t aad_len)

{

    int rv = CRYPTO_gcm128_aad(&ctx->gcm, aad, aad_len);

    /*

     * CRYPTO_gcm128_aad() returns:

     * -  0: success -> return 1

     * - -1: AAD length overflow -> propagate

     * - -2: AAD follows the payload -> propagate

     */

    if (rv == 0)

        return 1;

    return rv;

}

int ossl_gcm_cipher_update(PROV_GCM_CTX *ctx, const unsigned char *in,

    size_t len, unsigned char *out)

{

    if (ctx->enc) {

        if (CRYPTO_gcm128_encrypt(&ctx->gcm, in, out, len))

            return 0;

    } else {

        if (CRYPTO_gcm128_decrypt(&ctx->gcm, in, out, len))

            return 0;

    }

    return 1;

}

int ossl_gcm_cipher_final(PROV_GCM_CTX *ctx, unsigned char *tag)

{

    if (ctx->enc) {

        CRYPTO_gcm128_tag(&ctx->gcm, tag, GCM_TAG_MAX_SIZE);

        ctx->taglen = GCM_TAG_MAX_SIZE;

    } else {

        if (CRYPTO_gcm128_finish(&ctx->gcm, tag, ctx->taglen) != 0)

            return 0;

    }

    return 1;

}

int ossl_gcm_one_shot(PROV_GCM_CTX *ctx, unsigned char *aad, size_t aad_len,

    const unsigned char *in, size_t in_len,

    unsigned char *out, unsigned char *tag, size_t tag_len)

{

    int ret = 0;

    /* Use saved AAD */

    if (ctx->hw->aadupdate(ctx, aad, aad_len) <= 0)

        goto err;

    if (!ctx->hw->cipherupdate(ctx, in, in_len, out))

        goto err;

    ctx->taglen = GCM_TAG_MAX_SIZE;

    if (!ctx->hw->cipherfinal(ctx, tag))

        goto err;

    ret = 1;

err:

    return ret;

}