firmware/test/test_crypto/test_main.cpp

#include "CryptoEngine.h"

#include <unity.h>

void HexToBytes(uint8_t *result, const std::string hex, size_t len = 0)
{
    if (len) {
        memset(result, 0, len);
    }
    for (unsigned int i = 0; i < hex.length(); i += 2) {
        std::string byteString = hex.substr(i, 2);
        result[i / 2] = (uint8_t)strtol(byteString.c_str(), NULL, 16);
    }
    return;
}

void setUp(void)
{
    // set stuff up here
}

void tearDown(void)
{
    // clean stuff up here
}

void test_SHA256(void)
{
    uint8_t expected[32];
    uint8_t hash[32] = {0};

    HexToBytes(expected, "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855");
    crypto->hash(hash, 0);
    TEST_ASSERT_EQUAL_MEMORY(hash, expected, 32);

    HexToBytes(hash, "d3", 32);
    HexToBytes(expected, "28969cdfa74a12c82f3bad960b0b000aca2ac329deea5c2328ebc6f2ba9802c1");
    crypto->hash(hash, 1);
    TEST_ASSERT_EQUAL_MEMORY(hash, expected, 32);

    HexToBytes(hash, "11af", 32);
    HexToBytes(expected, "5ca7133fa735326081558ac312c620eeca9970d1e70a4b95533d956f072d1f98");
    crypto->hash(hash, 2);
    TEST_ASSERT_EQUAL_MEMORY(hash, expected, 32);
}
void test_ECB_AES256(void)
{
    // https://csrc.nist.gov/CSRC/media/Projects/Cryptographic-Standards-and-Guidelines/documents/examples/AES_ECB.pdf

    uint8_t key[32] = {0};
    uint8_t plain[16] = {0};
    uint8_t result[16] = {0};
    uint8_t expected[16] = {0};

    HexToBytes(key, "603DEB1015CA71BE2B73AEF0857D77811F352C073B6108D72D9810A30914DFF4");

    HexToBytes(plain, "6BC1BEE22E409F96E93D7E117393172A");
    HexToBytes(expected, "F3EED1BDB5D2A03C064B5A7E3DB181F8");
    crypto->aesSetKey(key, 32);
    crypto->aesEncrypt(plain, result); // Does 16 bytes at a time
    TEST_ASSERT_EQUAL_MEMORY(expected, result, 16);

    HexToBytes(plain, "AE2D8A571E03AC9C9EB76FAC45AF8E51");
    HexToBytes(expected, "591CCB10D410ED26DC5BA74A31362870");
    crypto->aesSetKey(key, 32);
    crypto->aesEncrypt(plain, result); // Does 16 bytes at a time
    TEST_ASSERT_EQUAL_MEMORY(expected, result, 16);

    HexToBytes(plain, "30C81C46A35CE411E5FBC1191A0A52EF");
    HexToBytes(expected, "B6ED21B99CA6F4F9F153E7B1BEAFED1D");
    crypto->aesSetKey(key, 32);
    crypto->aesEncrypt(plain, result); // Does 16 bytes at a time
    TEST_ASSERT_EQUAL_MEMORY(expected, result, 16);
}
void test_DH25519(void)
{
    // test vectors from wycheproof x25519
    // https://github.com/C2SP/wycheproof/blob/master/testvectors/x25519_test.json
    uint8_t private_key[32];
    uint8_t public_key[32];
    uint8_t expected_shared[32];

    HexToBytes(public_key, "504a36999f489cd2fdbc08baff3d88fa00569ba986cba22548ffde80f9806829");
    HexToBytes(private_key, "c8a9d5a91091ad851c668b0736c1c9a02936c0d3ad62670858088047ba057475");
    HexToBytes(expected_shared, "436a2c040cf45fea9b29a0cb81b1f41458f863d0d61b453d0a982720d6d61320");
    crypto->setDHPrivateKey(private_key);
    TEST_ASSERT(crypto->setDHPublicKey(public_key));
    TEST_ASSERT_EQUAL_MEMORY(expected_shared, crypto->shared_key, 32);

    HexToBytes(public_key, "63aa40c6e38346c5caf23a6df0a5e6c80889a08647e551b3563449befcfc9733");
    HexToBytes(private_key, "d85d8c061a50804ac488ad774ac716c3f5ba714b2712e048491379a500211958");
    HexToBytes(expected_shared, "279df67a7c4611db4708a0e8282b195e5ac0ed6f4b2f292c6fbd0acac30d1332");
    crypto->setDHPrivateKey(private_key);
    TEST_ASSERT(crypto->setDHPublicKey(public_key));
    TEST_ASSERT_EQUAL_MEMORY(expected_shared, crypto->shared_key, 32);

    HexToBytes(public_key, "ecffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff7f");
    HexToBytes(private_key, "18630f93598637c35da623a74559cf944374a559114c7937811041fc8605564a");
    crypto->setDHPrivateKey(private_key);
    TEST_ASSERT(!crypto->setDHPublicKey(public_key)); // Weak public key results in 0 shared key
}
void test_AES_CTR(void)
{
    uint8_t expected[32];
    uint8_t plain[32];
    uint8_t nonce[32];
    CryptoKey k;

    // vectors from https://www.rfc-editor.org/rfc/rfc3686#section-6
    k.length = 32;
    HexToBytes(k.bytes, "776BEFF2851DB06F4C8A0542C8696F6C6A81AF1EEC96B4D37FC1D689E6C1C104");
    HexToBytes(nonce, "00000060DB5672C97AA8F0B200000001");
    HexToBytes(expected, "145AD01DBF824EC7560863DC71E3E0C0");
    memcpy(plain, "Single block msg", 16);

    crypto->encryptAESCtr(k, nonce, 16, plain);
    TEST_ASSERT_EQUAL_MEMORY(expected, plain, 16);

    k.length = 16;
    memcpy(plain, "Single block msg", 16);
    HexToBytes(k.bytes, "AE6852F8121067CC4BF7A5765577F39E");
    HexToBytes(nonce, "00000030000000000000000000000001");
    HexToBytes(expected, "E4095D4FB7A7B3792D6175A3261311B8");
    crypto->encryptAESCtr(k, nonce, 16, plain);
    TEST_ASSERT_EQUAL_MEMORY(expected, plain, 16);
}

void setup()
{
    // NOTE!!! Wait for >2 secs
    // if board doesn't support software reset via Serial.DTR/RTS
    delay(2000);

    UNITY_BEGIN(); // IMPORTANT LINE!
    RUN_TEST(test_SHA256);
    RUN_TEST(test_ECB_AES256);
    RUN_TEST(test_DH25519);
    RUN_TEST(test_AES_CTR);
}

void loop()
{
    UNITY_END(); // stop unit testing
}