/*
 * Copyright (C) 2017 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License 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.
 */

/**
 * This app tests the API in app/keymaster/secure_storage_manager.h. To run this
 * test, include trusty/user/app/keymaster/device_unittest in
 * TRUSTY_ALL_USER_TASKS, and it will be start once an RPMB proxy becomes
 * available.
 *
 * Different application has different namespace, so this would not affect the
 * keymaster app's RPMB storage.
 */

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

#define typeof(x) __typeof__(x)
#include <lib/storage/storage.h>
#include <lib/unittest/unittest.h>
#include <trusty_unittest.h>

#include <keymaster/UniquePtr.h>
#include <keymaster/android_keymaster_utils.h>
#include "second_imei_attestation.h"
#include "secure_storage_manager.h"

#include "trusty_logger.h"

#define DATA_SIZE 1000
#define CHAIN_LENGTH 3

#define TLOG_TAG "km_storage_test"

using keymaster::AttestationKeySlot;
using keymaster::calculate_luhn_checksum_digit;
using keymaster::CertificateChain;
using keymaster::kAttestationUuidSize;
using keymaster::KeymasterKeyBlob;
using keymaster::kProductIdSize;
using keymaster::SecureStorageManager;
using keymaster::validate_second_imei;

uint8_t* NewRandBuf(uint32_t size) {
    uint8_t* buf = new uint8_t[size];
    if (buf == nullptr) {
        return nullptr;
    }
    for (uint8_t* i = buf;
         reinterpret_cast<size_t>(i) < reinterpret_cast<size_t>(buf) + size;
         i++) {
        *i = static_cast<uint8_t>(rand() % UINT8_MAX);
    }
    return buf;
}

void TestKeyStorage(SecureStorageManager* ss_manager,
                    AttestationKeySlot key_slot) {
    keymaster_error_t error = KM_ERROR_OK;
    keymaster::UniquePtr<uint8_t[]> write_key;
    KeymasterKeyBlob key_blob;
    bool key_exists = false;

    write_key.reset(NewRandBuf(DATA_SIZE));
    ASSERT_NE(nullptr, write_key.get());

    error = ss_manager->WriteKeyToStorage(key_slot, write_key.get(), DATA_SIZE);
    ASSERT_EQ(KM_ERROR_OK, error);

    key_blob = ss_manager->ReadKeyFromStorage(key_slot, &error);
    ASSERT_EQ(KM_ERROR_OK, error);
    ASSERT_EQ(DATA_SIZE, key_blob.key_material_size);
    ASSERT_NE(nullptr, write_key.get());
    ASSERT_NE(nullptr, key_blob.key_material);
    ASSERT_EQ(0, memcmp(write_key.get(), key_blob.key_material, DATA_SIZE));

    error = ss_manager->AttestationKeyExists(key_slot, &key_exists);
    ASSERT_EQ(KM_ERROR_OK, error);
    ASSERT_EQ(true, key_exists);

test_abort:;
}

void TestCertChainStorage(SecureStorageManager* ss_manager,
                          AttestationKeySlot key_slot,
                          bool chain_exists) {
    keymaster_error_t error = KM_ERROR_OK;
    keymaster::UniquePtr<uint8_t[]> write_cert[CHAIN_LENGTH];
    unsigned int i = 0;
    uint32_t cert_chain_length;
    CertificateChain chain;

    for (i = 0; i < CHAIN_LENGTH; ++i) {
        write_cert[i].reset(NewRandBuf(DATA_SIZE));
        ASSERT_NE(nullptr, write_cert[i].get());

        error = ss_manager->WriteCertToStorage(key_slot, write_cert[i].get(),
                                               DATA_SIZE, i);
        ASSERT_EQ(KM_ERROR_OK, error);

        error = ss_manager->ReadCertChainLength(key_slot, &cert_chain_length);
        ASSERT_EQ(KM_ERROR_OK, error);
        if (chain_exists) {
            ASSERT_EQ(3, cert_chain_length);
        } else {
            ASSERT_EQ(i + 1, cert_chain_length);
        }
    }

    error = ss_manager->ReadCertChainFromStorage(key_slot, &chain);
    ASSERT_EQ(KM_ERROR_OK, error);
    ASSERT_EQ(CHAIN_LENGTH, chain.entry_count);
    for (i = 0; i < CHAIN_LENGTH; ++i) {
        ASSERT_EQ(DATA_SIZE, chain.entries[i].data_length);
        ASSERT_EQ(0, memcmp(write_cert[i].get(), chain.entries[i].data,
                            DATA_SIZE));
    }

test_abort:;
}

void TestCertStorageInvalid(SecureStorageManager* ss_manager,
                            AttestationKeySlot key_slot) {
    keymaster_error_t error = KM_ERROR_OK;
    keymaster::UniquePtr<uint8_t[]> write_cert;
    uint32_t cert_chain_length;

    // Clear existing certificate chain
    error = ss_manager->DeleteKey(key_slot, true);
    error = ss_manager->ReadCertChainLength(key_slot, &cert_chain_length);
    ASSERT_EQ(KM_ERROR_OK, error);
    ASSERT_EQ(0, cert_chain_length);

    // Try to write to index (chain_length + 1)
    write_cert.reset(NewRandBuf(DATA_SIZE));
    ASSERT_NE(nullptr, write_cert.get());
    error = ss_manager->WriteCertToStorage(key_slot, write_cert.get(),
                                           DATA_SIZE, 1);
    ASSERT_EQ(KM_ERROR_INVALID_ARGUMENT, error);

    // Verify that cert chain length didn't change
    error = ss_manager->ReadCertChainLength(key_slot, &cert_chain_length);
    ASSERT_EQ(KM_ERROR_OK, error);
    ASSERT_EQ(0, cert_chain_length);

test_abort:;
}

void DeleteAttestationData(SecureStorageManager* ss_manager) {
    keymaster_error_t error = KM_ERROR_OK;
    uint32_t cert_chain_length;
    bool key_exists;

    error = ss_manager->DeleteAllAttestationData();
    ASSERT_EQ(KM_ERROR_OK, error);

    error = ss_manager->ReadCertChainLength(AttestationKeySlot::kRsa,
                                            &cert_chain_length);
    ASSERT_EQ(KM_ERROR_OK, error);
    ASSERT_EQ(0, cert_chain_length);
    error = ss_manager->ReadCertChainLength(AttestationKeySlot::kEcdsa,
                                            &cert_chain_length);
    ASSERT_EQ(KM_ERROR_OK, error);
    ASSERT_EQ(0, cert_chain_length);

    error = ss_manager->AttestationKeyExists(AttestationKeySlot::kRsa,
                                             &key_exists);
    ASSERT_EQ(KM_ERROR_OK, error);
    ASSERT_EQ(false, key_exists);
    error = ss_manager->AttestationKeyExists(AttestationKeySlot::kEcdsa,
                                             &key_exists);
    ASSERT_EQ(KM_ERROR_OK, error);
    ASSERT_EQ(false, key_exists);

test_abort:;
}

void TestUuidStorage(SecureStorageManager* ss_manager) {
    keymaster_error_t error = KM_ERROR_OK;
    keymaster::UniquePtr<uint8_t[]> write_uuid;
    keymaster::UniquePtr<uint8_t[]> read_uuid(
            new uint8_t[kAttestationUuidSize]);

    error = ss_manager->DeleteAttestationUuid();
    ASSERT_EQ(KM_ERROR_OK, error);

    write_uuid.reset(NewRandBuf(kAttestationUuidSize));
    ASSERT_NE(nullptr, write_uuid.get());

    error = ss_manager->WriteAttestationUuid((const uint8_t*)write_uuid.get());
    ASSERT_EQ(KM_ERROR_OK, error);

    error = ss_manager->ReadAttestationUuid(read_uuid.get());
    ASSERT_EQ(KM_ERROR_OK, error);
    ASSERT_NE(nullptr, read_uuid.get());
    ASSERT_EQ(0, memcmp(write_uuid.get(), read_uuid.get(), kProductIdSize));

    error = ss_manager->DeleteAttestationUuid();
    ASSERT_EQ(KM_ERROR_OK, error);

test_abort:;
}

void TestProductIdStorage(SecureStorageManager* ss_manager) {
    keymaster_error_t error = KM_ERROR_OK;
    keymaster::UniquePtr<uint8_t[]> write_productid;
    keymaster::UniquePtr<uint8_t[]> read_productid(new uint8_t[kProductIdSize]);

    error = ss_manager->DeleteProductId();
    ASSERT_EQ(KM_ERROR_OK, error);

    write_productid.reset(NewRandBuf(kProductIdSize));
    ASSERT_NE(nullptr, write_productid.get());

    error = ss_manager->SetProductId((const uint8_t*)write_productid.get());
    ASSERT_EQ(KM_ERROR_OK, error);

    error = ss_manager->ReadProductId(read_productid.get());
    ASSERT_EQ(KM_ERROR_OK, error);
    ASSERT_NE(nullptr, read_productid.get());
    ASSERT_EQ(0, memcmp(write_productid.get(), read_productid.get(),
                        kProductIdSize));

    error = ss_manager->DeleteProductId();
    ASSERT_EQ(KM_ERROR_OK, error);

test_abort:;
}

void TestProductIdStoragePreventOverwrite(SecureStorageManager* ss_manager) {
    keymaster_error_t error = KM_ERROR_OK;
    keymaster::UniquePtr<uint8_t[]> write_productid;
    keymaster::UniquePtr<uint8_t[]> overwrite_productid;
    keymaster::UniquePtr<uint8_t[]> read_productid(new uint8_t[kProductIdSize]);

    error = ss_manager->DeleteProductId();
    ASSERT_EQ(KM_ERROR_OK, error);

    write_productid.reset(NewRandBuf(kProductIdSize));
    ASSERT_NE(nullptr, write_productid.get());

    error = ss_manager->SetProductId((const uint8_t*)write_productid.get());
    ASSERT_EQ(KM_ERROR_OK, error);

    overwrite_productid.reset(NewRandBuf(kProductIdSize));
    error = ss_manager->SetProductId((const uint8_t*)write_productid.get());
    ASSERT_EQ(KM_ERROR_INVALID_ARGUMENT, error);

    error = ss_manager->ReadProductId(read_productid.get());
    ASSERT_EQ(KM_ERROR_OK, error);
    ASSERT_NE(nullptr, read_productid.get());
    ASSERT_EQ(0, memcmp(write_productid.get(), read_productid.get(),
                        kProductIdSize));

    error = ss_manager->DeleteProductId();
    ASSERT_EQ(KM_ERROR_OK, error);

test_abort:;
}

void TestLuhnChecksumCalculation() {
    ASSERT_EQ(0u, calculate_luhn_checksum_digit(0));
    ASSERT_EQ(3, calculate_luhn_checksum_digit(7992739871ul));
    ASSERT_EQ(3, calculate_luhn_checksum_digit(7992739871ul));
    ASSERT_EQ(6, calculate_luhn_checksum_digit(735423462345ul));
    ASSERT_EQ(4, calculate_luhn_checksum_digit(721367498765427ul));
test_abort:;
}

keymaster_blob_t toBlob(const char* str) {
    return {reinterpret_cast<const uint8_t*>(str), strlen(str)};
}

void TestSecondImeiValidation() {
    // First IMEI used throughout the test
    const uint64_t first_imei = 721367498765404;
    // Sequential IMEI
    const char* second_imei = "721367498765412";
    // Valid IMEI, but not a sequential one
    const char* second_imei_not_seq = "721367498765420";
    // Invalid IMEI, not a sequential one.
    const char* invalid_imei = "721367498765437";
    // Invalid IMEI: Sequential to first_imei but the checksum digit is wrong.
    const char* invalid_seq_imei = "721367498765415";
    ASSERT_EQ(true, validate_second_imei(toBlob(second_imei), first_imei));

    ASSERT_EQ(false,
              validate_second_imei(toBlob(second_imei_not_seq), first_imei));
    ASSERT_EQ(false, validate_second_imei(toBlob(invalid_imei), first_imei));
    ASSERT_EQ(false,
              validate_second_imei(toBlob(invalid_seq_imei), first_imei));
test_abort:;
}

typedef struct {
    SecureStorageManager* ss_manager;
} KeymasterTest_t;

static void KeymasterTest_SetUp(KeymasterTest_t* state) {
    state->ss_manager = SecureStorageManager::get_instance();

    DeleteAttestationData(state->ss_manager);
}

static void KeymasterTest_TearDown(KeymasterTest_t* state) {
    DeleteAttestationData(state->ss_manager);
}

TEST_F(KeymasterTest, TestKeyStorageRsa) {
    TestKeyStorage(_state->ss_manager, AttestationKeySlot::kRsa);
}

TEST_F(KeymasterTest, TestKeyStorageEcdsa) {
    TestKeyStorage(_state->ss_manager, AttestationKeySlot::kEcdsa);
}

TEST_F(KeymasterTest, TestCertChainStorageRsa) {
    TestCertChainStorage(_state->ss_manager, AttestationKeySlot::kRsa, false);
}

TEST_F(KeymasterTest, TestCertChainStorageEcdsa) {
    TestCertChainStorage(_state->ss_manager, AttestationKeySlot::kEcdsa, false);
}

TEST_F(KeymasterTest, TestRewriteKey) {
    TestKeyStorage(_state->ss_manager, AttestationKeySlot::kRsa);
    // Rewriting keys should work
    TestKeyStorage(_state->ss_manager, AttestationKeySlot::kRsa);
}

TEST_F(KeymasterTest, TestRewriteChain) {
    TestCertChainStorage(_state->ss_manager, AttestationKeySlot::kRsa, false);
    TestCertChainStorage(_state->ss_manager, AttestationKeySlot::kRsa, true);
}

TEST_F(KeymasterTest, TestCertStorageInvalid) {
    TestCertStorageInvalid(_state->ss_manager, AttestationKeySlot::kRsa);
}

TEST_F(KeymasterTest, TestUuidStorage) {
    TestUuidStorage(_state->ss_manager);
}

TEST_F(KeymasterTest, TestProductIdStorage) {
    TestProductIdStorage(_state->ss_manager);
}

TEST_F(KeymasterTest, TestLuhnChecksumCalculation) {
    TestLuhnChecksumCalculation();
}

TEST_F(KeymasterTest, TestSecondImeiValidation) {
    TestSecondImeiValidation();
}

#ifndef KEYMASTER_DEBUG
TEST_F(KeymasterTest, TestProductIdStoragePreventOverwrite) {
    TestProductIdStoragePreventOverwrite(_state->ss_manager);
}
#endif

static bool keymaster_test(struct unittest* test) {
    return RUN_ALL_TESTS();
}

#define PORT_BASE "com.android.keymaster-unittest"

int main(void) {
    keymaster::TrustyLogger::initialize();

    struct unittest keymaster_unittest = {
            .port_name = PORT_BASE,
            .run_test = keymaster_test,
    };
    struct unittest* keymaster_unittest_p = &keymaster_unittest;
    return unittest_main(&keymaster_unittest_p, 1);
}