/*
 * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License").
 * You may not use this file except in compliance with the License.
 * A copy of the License is located at
 *
 *  http://aws.amazon.com/apache2.0
 *
 * or in the "license" file accompanying this file. This file is distributed
 * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
 * express or implied. See the License for the specific language governing
 * permissions and limitations under the License.
 */

#include <stdio.h>
#include <string.h>

#include "api/s2n.h"
#include "crypto/s2n_cipher.h"
#include "crypto/s2n_fips.h"
#include "crypto/s2n_hmac.h"
#include "crypto/s2n_openssl.h"
#include "s2n_test.h"
#include "stuffer/s2n_stuffer.h"
#include "testlib/s2n_testlib.h"
#include "tls/s2n_cipher_suites.h"
#include "tls/s2n_prf.h"
#include "tls/s2n_record.h"
#include "utils/s2n_random.h"

int main(int argc, char **argv)
{
    BEGIN_TEST();

    /* Test Openssl-3.0 does not support RC4 */
    if (S2N_OPENSSL_VERSION_AT_LEAST(3, 0, 0)) {
        EXPECT_FALSE(s2n_rc4.is_available());
    }

    /* Test FIPS does not support RC4 */
    if (s2n_is_in_fips_mode()) {
        EXPECT_FALSE(s2n_rc4.is_available());
    }

    struct s2n_connection *conn = NULL;
    uint8_t mac_key[] = "sample mac key";
    uint8_t rc4_key[] = "123456789012345";
    struct s2n_blob key_iv = { 0 };
    EXPECT_SUCCESS(s2n_blob_init(&key_iv, rc4_key, sizeof(rc4_key)));
    uint8_t random_data[S2N_DEFAULT_FRAGMENT_LENGTH + 1];
    struct s2n_blob r = { 0 };
    EXPECT_SUCCESS(s2n_blob_init(&r, random_data, sizeof(random_data)));

    EXPECT_SUCCESS(s2n_disable_tls13_in_test());

    if (s2n_is_in_fips_mode()) {
        /* Skip when FIPS mode is set as FIPS mode does not support RC4 */
        END_TEST();
    }

    EXPECT_NOT_NULL(conn = s2n_connection_new(S2N_SERVER));
    EXPECT_OK(s2n_get_public_random_data(&r));

    /* Peer and we are in sync */
    conn->server = conn->secure;
    conn->client = conn->secure;

    /* test the RC4 cipher with a SHA1 hash */
    conn->secure->cipher_suite->record_alg = &s2n_record_alg_rc4_sha;
    EXPECT_OK(conn->secure->cipher_suite->record_alg->cipher->init(&conn->secure->server_key));
    EXPECT_OK(conn->secure->cipher_suite->record_alg->cipher->init(&conn->secure->client_key));
    if (conn->secure->cipher_suite->record_alg->cipher->is_available()) {
        EXPECT_OK(conn->secure->cipher_suite->record_alg->cipher->set_decryption_key(&conn->secure->client_key, &key_iv));
        EXPECT_OK(conn->secure->cipher_suite->record_alg->cipher->set_encryption_key(&conn->secure->server_key, &key_iv));
        EXPECT_SUCCESS(s2n_hmac_init(&conn->secure->client_record_mac, S2N_HMAC_SHA1, mac_key, sizeof(mac_key)));
        EXPECT_SUCCESS(s2n_hmac_init(&conn->secure->server_record_mac, S2N_HMAC_SHA1, mac_key, sizeof(mac_key)));
        conn->actual_protocol_version = S2N_TLS11;

        for (size_t i = 0; i <= S2N_DEFAULT_FRAGMENT_LENGTH + 1; i++) {
            struct s2n_blob in = { 0 };
            EXPECT_SUCCESS(s2n_blob_init(&in, random_data, i));
            int bytes_written = 0;

            EXPECT_SUCCESS(s2n_stuffer_wipe(&conn->out));

            s2n_result result = s2n_record_write(conn, TLS_APPLICATION_DATA, &in);
            if (i <= S2N_DEFAULT_FRAGMENT_LENGTH) {
                EXPECT_OK(result);
                bytes_written = i;
            } else {
                EXPECT_ERROR_WITH_ERRNO(result, S2N_ERR_FRAGMENT_LENGTH_TOO_LARGE);
                bytes_written = S2N_DEFAULT_FRAGMENT_LENGTH;
            }

            uint16_t predicted_length = bytes_written + 20;
            EXPECT_EQUAL(conn->out.blob.data[0], TLS_APPLICATION_DATA);
            EXPECT_EQUAL(conn->out.blob.data[1], 3);
            EXPECT_EQUAL(conn->out.blob.data[2], 2);
            EXPECT_EQUAL(conn->out.blob.data[3], (predicted_length >> 8) & 0xff);
            EXPECT_EQUAL(conn->out.blob.data[4], predicted_length & 0xff);

            /* The data should be encrypted */
            if (bytes_written > 10) {
                EXPECT_NOT_EQUAL(memcmp(conn->out.blob.data + 5, random_data, bytes_written), 0);
            }

            /* Copy the encrypted out data to the in data */
            EXPECT_SUCCESS(s2n_stuffer_wipe(&conn->in));
            EXPECT_SUCCESS(s2n_stuffer_wipe(&conn->header_in));
            EXPECT_SUCCESS(s2n_stuffer_copy(&conn->out, &conn->header_in, 5));
            EXPECT_SUCCESS(s2n_stuffer_copy(&conn->out, &conn->in, s2n_stuffer_data_available(&conn->out)));

            /* Check that the data looks right */
            EXPECT_EQUAL(bytes_written + 20, s2n_stuffer_data_available(&conn->in));

            /* Let's decrypt it */
            uint8_t content_type = 0;
            uint16_t fragment_length = 0;
            EXPECT_SUCCESS(s2n_record_header_parse(conn, &content_type, &fragment_length));
            EXPECT_SUCCESS(s2n_record_parse(conn));
            EXPECT_EQUAL(content_type, TLS_APPLICATION_DATA);
            EXPECT_EQUAL(fragment_length, predicted_length);

            EXPECT_SUCCESS(s2n_stuffer_wipe(&conn->header_in));
            EXPECT_SUCCESS(s2n_stuffer_wipe(&conn->in));
        }

        EXPECT_OK(conn->secure->cipher_suite->record_alg->cipher->destroy_key(&conn->secure->server_key));
        EXPECT_OK(conn->secure->cipher_suite->record_alg->cipher->destroy_key(&conn->secure->client_key));
    } else {
        EXPECT_ERROR_WITH_ERRNO(conn->secure->cipher_suite->record_alg->cipher->set_decryption_key(&conn->secure->client_key, &key_iv), S2N_ERR_KEY_INIT);
        EXPECT_ERROR_WITH_ERRNO(conn->secure->cipher_suite->record_alg->cipher->set_encryption_key(&conn->secure->server_key, &key_iv), S2N_ERR_KEY_INIT);
    }
    EXPECT_SUCCESS(s2n_connection_free(conn));
    END_TEST();
}
