/*!
 * \file gnss_crypto_test.cc
 * \brief Tests for the Gnss_Crypto class.
 * \author Carles Fernandez, 2023-2024. cfernandez(at)cttc.es
 *   Cesare Ghionoiu Martinez, 2023-2024. c.ghionoiu-martinez@tu-braunschweig.de
 *
 *
 * -----------------------------------------------------------------------------
 *
 * GNSS-SDR is a Global Navigation Satellite System software-defined receiver.
 * This file is part of GNSS-SDR.
 *
 * Copyright (C) 2010-2024  (see AUTHORS file for a list of contributors)
 * SPDX-License-Identifier: GPL-3.0-or-later
 *
 * -----------------------------------------------------------------------------
 */

#include "gnss_crypto.h"
#include "gnss_sdr_filesystem.h"
#include "gnss_sdr_make_unique.h"
#include <gtest/gtest.h>
#include <fstream>
#include <iterator>
#include <utility>

class GnssCryptoTest : public ::testing::Test
{
};


TEST(GnssCryptoTest, VerifyPubKeyImport)
{
    auto d_crypto = std::make_unique<Gnss_Crypto>();
    // Input taken from RG 1.3 A7.1
    // compressed ECDSA P-256 format
    std::vector<uint8_t> publicKey = {
        0x03, 0x03, 0xB2, 0xCE, 0x64, 0xBC, 0x20, 0x7B, 0xDD, 0x8B,
        0xC4, 0xDF, 0x85, 0x91, 0x87, 0xFC, 0xB6, 0x86, 0x32, 0x0D,
        0x63, 0xFF, 0xA0, 0x91, 0x41, 0x0F, 0xC1, 0x58, 0xFB, 0xB7,
        0x79, 0x80, 0xEA};

    ASSERT_FALSE(d_crypto->have_public_key());

    d_crypto->set_public_key(publicKey);

    ASSERT_TRUE(d_crypto->have_public_key());
}


TEST(GnssCryptoTest, VerifyPublicKeyStorage)
{
    const std::string f1("./osnma_test_file1.pem");
    const std::string f2("./osnma_test_file2.pem");
    const std::string f3("./osnma_test_file3.pem");

    // Input taken from RG 1.3 A7.1
    // compressed ECDSA P-256 format
    std::vector<uint8_t> publicKey = {
        0x03, 0x03, 0xB2, 0xCE, 0x64, 0xBC, 0x20, 0x7B, 0xDD, 0x8B,
        0xC4, 0xDF, 0x85, 0x91, 0x87, 0xFC, 0xB6, 0x86, 0x32, 0x0D,
        0x63, 0xFF, 0xA0, 0x91, 0x41, 0x0F, 0xC1, 0x58, 0xFB, 0xB7,
        0x79, 0x80, 0xEA};

    auto d_crypto = std::make_unique<Gnss_Crypto>();
    ASSERT_FALSE(d_crypto->have_public_key());
    ASSERT_TRUE(d_crypto->get_public_key_type() == "Unknown");
    d_crypto->set_public_key(publicKey);
    ASSERT_TRUE(d_crypto->have_public_key());
    ASSERT_TRUE(d_crypto->store_public_key(f1));

    auto d_crypto2 = std::make_unique<Gnss_Crypto>(f1, "");
    ASSERT_TRUE(d_crypto2->have_public_key());
    ASSERT_TRUE(d_crypto2->get_public_key_type() == "ECDSA P-256");
    ASSERT_TRUE(d_crypto2->store_public_key(f2));

    std::ifstream t(f1);
    std::string content_file((std::istreambuf_iterator<char>(t)), std::istreambuf_iterator<char>());

    std::ifstream t2(f2);
    std::string content_file2((std::istreambuf_iterator<char>(t2)), std::istreambuf_iterator<char>());

    ASSERT_EQ(content_file, content_file2);

    // P-521 Public key in compressed X format
    std::vector<uint8_t> publicKey_P521 = {
        0x03, 0x00, 0x28, 0x35, 0xBB, 0xE9, 0x24, 0x59, 0x4E, 0xF0,
        0xE3, 0xA2, 0xDB, 0xC0, 0x49, 0x30, 0x60, 0x7C, 0x61, 0x90,
        0xE4, 0x03, 0xE0, 0xC7, 0xB8, 0xC2, 0x62, 0x37, 0xF7, 0x58,
        0x56, 0xBE, 0x63, 0x5C, 0x97, 0xF7, 0x53, 0x64, 0x7E, 0xE1,
        0x0C, 0x07, 0xD3, 0x97, 0x8D, 0x58, 0x46, 0xFD, 0x6E, 0x06,
        0x44, 0x01, 0xA7, 0xAA, 0xC4, 0x95, 0x13, 0x5D, 0xC9, 0x77,
        0x26, 0xE9, 0xF8, 0x72, 0x0C, 0xD3, 0x88};

    d_crypto->set_public_key(publicKey_P521);
    ASSERT_TRUE(d_crypto->have_public_key());
    ASSERT_TRUE(d_crypto->get_public_key_type() == "ECDSA P-521");
    ASSERT_TRUE(d_crypto->store_public_key(f3));

    auto d_crypto3 = std::make_unique<Gnss_Crypto>(f3, "");
    ASSERT_TRUE(d_crypto3->have_public_key());
    ASSERT_TRUE(d_crypto3->get_public_key_type() == "ECDSA P-521");

    std::vector<uint8_t> wrong_publicKey = {
        0x03, 0x03, 0xB2, 0xCE, 0x64, 0xBC, 0x20, 0x7B, 0xDD, 0x8B,
        0xC4, 0xDF, 0x85, 0x91, 0x87, 0xFC, 0xB6, 0x86, 0x32, 0x0D,
        0x63, 0xFF, 0xA0};

    auto d_crypto4 = std::make_unique<Gnss_Crypto>();
    d_crypto4->set_public_key(wrong_publicKey);
    ASSERT_FALSE(d_crypto4->have_public_key());
    ASSERT_TRUE(d_crypto4->get_public_key_type() == "Unknown");

    errorlib::error_code ec;
    ASSERT_TRUE(fs::remove(fs::path(f1), ec));
    ASSERT_TRUE(fs::remove(fs::path(f2), ec));
    ASSERT_TRUE(fs::remove(fs::path(f3), ec));
}


TEST(GnssCryptoTest, TestComputeSHA_256)
{
    auto d_crypto = std::make_unique<Gnss_Crypto>();
    std::vector<uint8_t> message{
        0x48, 0x65, 0x6C, 0x6C, 0x6F, 0x20, 0x77, 0x6F, 0x72, 0x6C, 0x64, 0x0A};  // Hello world

    std::vector<uint8_t> expected_output = {
        0x18, 0x94, 0xA1, 0x9C, 0x85, 0xBA, 0x15, 0x3A, 0xCB, 0xF7,
        0x43, 0xAC, 0x4E, 0x43, 0xFC, 0x00, 0x4C, 0x89, 0x16, 0x04,
        0xB2, 0x6F, 0x8C, 0x69, 0xE1, 0xE8, 0x3E, 0xA2, 0xAF, 0xC7,
        0xC4, 0x8F};

    std::vector<uint8_t> output = d_crypto->compute_SHA_256(message);

    ASSERT_EQ(expected_output, output);
}


TEST(GnssCryptoTest, TestComputeSHA3_256)
{
    auto d_crypto = std::make_unique<Gnss_Crypto>();
    std::vector<uint8_t> message{
        0x48, 0x65, 0x6C, 0x6C, 0x6F, 0x20, 0x77, 0x6F, 0x72, 0x6C, 0x64, 0x0A};  // Hello world

    std::vector<uint8_t> expected_output = {
        0xCC, 0xB8, 0xF9, 0x23, 0x5F, 0x4A, 0x93, 0x2C, 0xA0, 0xAB,
        0xBB, 0x2C, 0x24, 0x36, 0x72, 0x5E, 0x2E, 0x8D, 0xC7, 0x5B,
        0x99, 0xE7, 0xF6, 0xC4, 0x50, 0x5B, 0x2A, 0x93, 0x6E, 0xB6,
        0x3B, 0x3F};

    std::vector<uint8_t> output = d_crypto->compute_SHA3_256(message);

    ASSERT_EQ(expected_output, output);
}


// Unit test for computeHMAC_SHA_256 function.
TEST(GnssCryptoTest, TestComputeHMACSHA256)
{
    auto d_crypto = std::make_unique<Gnss_Crypto>();

    std::vector<uint8_t> key = {
        0x24, 0x24, 0x3B, 0x76, 0xF9, 0x14, 0xB1, 0xA7,
        0x7D, 0x48, 0xE7, 0xF1, 0x48, 0x0C, 0xC2, 0x98,
        0xEB, 0x62, 0x3E, 0x95, 0x6B, 0x2B, 0xCE, 0xA3,
        0xB4, 0xD4, 0xDB, 0x31, 0xEE, 0x96, 0xAB, 0xFA};

    std::vector<uint8_t> message{
        0x48, 0x65, 0x6C, 0x6C, 0x6F, 0x20, 0x77, 0x6F, 0x72, 0x6C, 0x64, 0x0A};  // Hello world

    std::vector<uint8_t> expected_output = {
        0xC3, 0x51, 0xF6, 0xFD, 0xDD, 0xC9, 0x8B, 0x41,
        0xD6, 0xF4, 0x77, 0x6D, 0xAC, 0xE8, 0xE0, 0x14,
        0xB2, 0x7A, 0xCC, 0x22, 0x00, 0xAA, 0xD2, 0x37,
        0xD0, 0x79, 0x06, 0x12, 0x83, 0x40, 0xB7, 0xA6};

    std::vector<uint8_t> output = d_crypto->compute_HMAC_SHA_256(key, message);

    ASSERT_EQ(expected_output, output);
}


TEST(GnssCryptoTest, TestComputeHMACSHA256_m0)
{
    // key and message generated from RG A.6.5.1
    auto d_crypto = std::make_unique<Gnss_Crypto>();

    // RG K4 @ 345690
    std::vector<uint8_t> key = {
        0x69, 0xC0, 0x0A, 0xA7, 0x36, 0x42, 0x37, 0xA6,
        0x5E, 0xBF, 0x00, 0x6A, 0xD8, 0xDD, 0xBC, 0x73};

    // m0
    std::vector<uint8_t> message = {
        0x02, 0x4E, 0x05, 0x46, 0x3C, 0x01, 0x83, 0xA5,
        0x91, 0x05, 0x1D, 0x69, 0x25, 0x80, 0x07, 0x6B,
        0x3E, 0xEA, 0x81, 0x41, 0xBF, 0x03, 0xAD, 0xCB,
        0x5A, 0xAD, 0xB2, 0x77, 0xAF, 0x6F, 0xCF, 0x21,
        0xFB, 0x98, 0xFF, 0x7E, 0x83, 0xAF, 0xFC, 0x37,
        0x02, 0x03, 0xB0, 0xD8, 0xE1, 0x0E, 0xB1, 0x4D,
        0x11, 0x18, 0xE6, 0xB0, 0xE8, 0x20, 0x01, 0xA0,
        0x00, 0xE5, 0x91, 0x00, 0x06, 0xD3, 0x1F, 0x00,
        0x02, 0x68, 0x05, 0x4A, 0x02, 0xC2, 0x26, 0x07,
        0xF7, 0xFC, 0x00};

    std::vector<uint8_t> expected_output = {
        0xE3, 0x7B, 0xC4, 0xF8, 0x58, 0xAE, 0x1E, 0x5C,
        0xFD, 0xC4, 0x6F, 0x05, 0x4B, 0x1F, 0x47, 0xB9,
        0xD2, 0xEA, 0x61, 0xE1, 0xEF, 0x09, 0x11, 0x5C,
        0xFE, 0x70, 0x68, 0x52, 0xBF, 0xF2, 0x3A, 0x83};

    std::vector<uint8_t> output = d_crypto->compute_HMAC_SHA_256(key, message);

    ASSERT_EQ(expected_output, output);
}


TEST(GnssCryptoTest, TestComputeHMACSHA256_adkd4)
{
    // key and message generated from RG A.6.5.2
    auto d_crypto = std::make_unique<Gnss_Crypto>();

    // RG K4 @ 345690
    std::vector<uint8_t> key = {
        0x69, 0xC0, 0x0A, 0xA7, 0x36, 0x42, 0x37, 0xA6,
        0x5E, 0xBF, 0x00, 0x6A, 0xD8, 0xDD, 0xBC, 0x73};

    std::vector<uint8_t> message = {
        0x02, 0x02, 0x4E, 0x05, 0x46, 0x3C, 0x03, 0xBF,
        0xFF, 0xFF, 0xFF, 0xC0, 0x00, 0x00, 0x44, 0x92,
        0x38, 0x22, 0x78, 0x97, 0xFD, 0xEF, 0xF9, 0x30,
        0x40};

    std::vector<uint8_t> expected_output = {
        0x7B, 0xB2, 0x38, 0xC8, 0x83, 0xC0, 0x6A, 0x2B,
        0x50, 0x8F, 0xE6, 0x3F, 0xB7, 0xF4, 0xF5, 0x4D,
        0x44, 0xAB, 0xEE, 0x4D, 0xCE, 0xB9, 0x3D, 0xCF,
        0x65, 0xCB, 0x3A, 0x5B, 0x81, 0x4A, 0x34, 0xE9};

    std::vector<uint8_t> output = d_crypto->compute_HMAC_SHA_256(key, message);

    ASSERT_EQ(expected_output, output);
}


TEST(GnssCryptoTest, TestComputeCMAC_AES)
{
    // Tests vectors from https://datatracker.ietf.org/doc/html/rfc4493#appendix-A
    auto d_crypto = std::make_unique<Gnss_Crypto>();

    std::vector<uint8_t> key = {
        0x2B, 0x7E, 0x15, 0x16, 0x28, 0xAE, 0xD2, 0xA6,
        0xAB, 0xF7, 0x15, 0x88, 0x09, 0xCF, 0x4F, 0x3C};

    std::vector<uint8_t> message{
        0x6B, 0xC1, 0xBE, 0xE2, 0x2E, 0x40, 0x9F, 0x96,
        0xE9, 0x3D, 0x7E, 0x11, 0x73, 0x93, 0x17, 0x2A};

    std::vector<uint8_t> expected_output = {
        0x07, 0x0A, 0x16, 0xB4, 0x6B, 0x4D, 0x41, 0x44,
        0xF7, 0x9B, 0xDD, 0x9D, 0xD0, 0x4A, 0x28, 0x7C};

    std::vector<uint8_t> output = d_crypto->compute_CMAC_AES(key, message);

    ASSERT_EQ(expected_output, output);
}


TEST(GnssCryptoTest, VerifySignatureP256)
{
    auto d_crypto = std::make_unique<Gnss_Crypto>();

    // RG example  - import crt certificate
    std::vector<uint8_t> message = {
        0x82, 0x10, 0x49, 0x22, 0x04, 0xE0, 0x60, 0x61, 0x0B, 0xDF,
        0x26, 0xD7, 0x7B, 0x5B, 0xF8, 0xC9, 0xCB, 0xFC, 0xF7, 0x04,
        0x22, 0x08, 0x14, 0x75, 0xFD, 0x44, 0x5D, 0xF0, 0xFF};

    // ECDSA P-256 signature, raw format
    std::vector<uint8_t> signature = {
        0xF8, 0xCD, 0x88, 0x29, 0x9F, 0xA4, 0x60, 0x58, 0x00, 0x20,
        0x7B, 0xFE, 0xBE, 0xAC, 0x55, 0x02, 0x40, 0x53, 0xF3, 0x0F,
        0x7C, 0x69, 0xB3, 0x5C, 0x15, 0xE6, 0x08, 0x00, 0xAC, 0x3B,
        0x6F, 0xE3, 0xED, 0x06, 0x39, 0x95, 0x2F, 0x7B, 0x02, 0x8D,
        0x86, 0x86, 0x74, 0x45, 0x96, 0x1F, 0xFE, 0x94, 0xFB, 0x22,
        0x6B, 0xFF, 0x70, 0x06, 0xE0, 0xC4, 0x51, 0xEE, 0x3F, 0x87,
        0x28, 0xC1, 0x77, 0xFB};

    // Input taken from RG 1.3 A7.1
    // compressed ECDSA P-256 format
    std::vector<uint8_t> publicKey = {
        0x03, 0x03, 0xB2, 0xCE, 0x64, 0xBC, 0x20, 0x7B, 0xDD, 0x8B,
        0xC4, 0xDF, 0x85, 0x91, 0x87, 0xFC, 0xB6, 0x86, 0x32, 0x0D,
        0x63, 0xFF, 0xA0, 0x91, 0x41, 0x0F, 0xC1, 0x58, 0xFB, 0xB7,
        0x79, 0x80, 0xEA};

    d_crypto->set_public_key(publicKey);
    ASSERT_TRUE(d_crypto->verify_signature_ecdsa_p256(message, signature));

    std::vector<uint8_t> wrong_signature = std::move(signature);
    wrong_signature[1] = 1;
    ASSERT_FALSE(d_crypto->verify_signature_ecdsa_p256(message, wrong_signature));
}


TEST(GnssCryptoTest, VerifySignatureP521)
{
    std::unique_ptr<Gnss_Crypto> d_crypto = std::make_unique<Gnss_Crypto>();

    // Message to be verified
    std::vector<uint8_t> message = {
        0x48, 0x65, 0x6C, 0x6C, 0x6F, 0x20, 0x77, 0x6F, 0x72, 0x6C, 0x64, 0x0A};  // "Hello world\n"

    // Public key in compressed X format
    std::vector<uint8_t> publicKey = {
        0x03, 0x00, 0x28, 0x35, 0xBB, 0xE9, 0x24, 0x59, 0x4E, 0xF0,
        0xE3, 0xA2, 0xDB, 0xC0, 0x49, 0x30, 0x60, 0x7C, 0x61, 0x90,
        0xE4, 0x03, 0xE0, 0xC7, 0xB8, 0xC2, 0x62, 0x37, 0xF7, 0x58,
        0x56, 0xBE, 0x63, 0x5C, 0x97, 0xF7, 0x53, 0x64, 0x7E, 0xE1,
        0x0C, 0x07, 0xD3, 0x97, 0x8D, 0x58, 0x46, 0xFD, 0x6E, 0x06,
        0x44, 0x01, 0xA7, 0xAA, 0xC4, 0x95, 0x13, 0x5D, 0xC9, 0x77,
        0x26, 0xE9, 0xF8, 0x72, 0x0C, 0xD3, 0x88};

    // ECDSA P-521 signature, raw format
    std::vector<uint8_t> signature = {
        0x01, 0x5C, 0x23, 0xC0, 0xBE, 0xAD, 0x1E, 0x44, 0x60, 0xD4,
        0xE0, 0x81, 0x38, 0xF2, 0xBA, 0xF5, 0xB5, 0x37, 0x5A, 0x34,
        0xB5, 0xCA, 0x6B, 0xC8, 0x0F, 0xCD, 0x75, 0x1D, 0x5E, 0xC0,
        0x8A, 0xD3, 0xD7, 0x79, 0xA7, 0xC1, 0xB8, 0xA2, 0xC6, 0xEA,
        0x5A, 0x7D, 0x60, 0x66, 0x50, 0x97, 0x37, 0x6C, 0xF9, 0x0A,
        0xF6, 0x3D, 0x77, 0x9A, 0xE2, 0x19, 0xF7, 0xF9, 0xDD, 0x52,
        0xC4, 0x0F, 0x98, 0xAA, 0xA2, 0xA4, 0x01, 0xC9, 0x41, 0x0B,
        0xD0, 0x25, 0xDD, 0xC9, 0x7C, 0x3F, 0x70, 0x32, 0x23, 0xCF,
        0xFE, 0x37, 0x67, 0x3A, 0xBC, 0x0B, 0x76, 0x16, 0x82, 0x83,
        0x27, 0x3D, 0x1D, 0x19, 0x15, 0x78, 0x08, 0x2B, 0xD4, 0xA7,
        0xC2, 0x0F, 0x11, 0xF4, 0xDD, 0xE5, 0x5A, 0x5D, 0x04, 0x8D,
        0x6D, 0x5E, 0xC4, 0x1F, 0x54, 0x44, 0xA9, 0x13, 0x34, 0x71,
        0x0F, 0xF7, 0x57, 0x9A, 0x9F, 0x2E, 0xF4, 0x97, 0x7D, 0xAE,
        0x28, 0xEF};

    d_crypto->set_public_key(publicKey);
    ASSERT_TRUE(d_crypto->verify_signature_ecdsa_p521(message, signature));

    std::vector<uint8_t> wrong_signature = std::move(signature);
    wrong_signature[1] = 1;
    ASSERT_FALSE(d_crypto->verify_signature_ecdsa_p521(message, wrong_signature));
}