🔐 Radikant Crypto C

Encrypt 🔒 Decrypt

Radikant Crypto is a cryptolibrary providing cryptograhpic primivitves such as ECC, Hash and various ciphers and mac’s. Written in C with no external dependencies.

Introduction

Radikant Crypto is a eductional (toy) implementation supporting common primitives. The cryptograhic core is seperated and decoupled. Currently works on arm64 hardware (apple silicon) and in software mode on 64 bit architecture, but can be easliy modified to run on other platforms or architectures aswell. Testing against RFC vectors has proven that the library is capable to produce the correct bit output. It used as dependency inside Radikant TLS , Radikant Noise and many other Radikant Projects. It supported primitives like AES , Diffie-hellman, KDF

⚠️ This library is an infamous example of “don’t roll your own crypto” it is incredibly insecure, branchy, leaks memory, information and secrets and is not constant time. It isnt fuzzed against malicious input. Cryptography is incredibly complex and it's suprisingly easy to get wrong, i'm not a Cryptographic expert. There is only handfull of situations where it would be acceptable to use and its not distributed software. In general i highly recommend against it.

Ciphers

Symmetric, Asysmetic, Block and Stream ciphers

AES

Advances Encryption Standard for arm64 supporting cbc, ccm, ctr, ecb and gcm modes.

ChaCha20

ChaCha with support for Poly1305 mac. Some arm64 support, by design for software mode.

Salsa20

Software only support for Salsa20 stream ciphers.

RSA

Bit accurate implementation of RSA for 2048 bit encryption.

Kuznyechik

Software only implementation of from 3th party source.

SM4

Software only implementation of SM4 cipher.

TwoFish

Software only implementation of TwoFish cipher from 3th party source.

Serpent

Software only implementation of TwoFish.

Example AES gcm

uint8_t key[32] = {
    0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
    0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
    0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
    0x18, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F
};
uint8_t iv[12] = {
    0xCA, 0xFE, 0xBA, 0xBE, 0xFA, 0xCE, 0xDB, 0xAD,
    0xDE, 0xCA, 0xF8, 0x88
};
const char *aad_str = "Metadata: Header info";
const char *pt_str = "Secret Message: The eagle has landed.";
uint8_t *aad = (uint8_t*)aad_str;     uint8_t *pt = (uint8_t*)pt_str;
size_t aad_len = strlen(aad_str);     size_t pt_len = strlen(pt_str);
// 3. Prepare Output Buffers
uint8_t ct[pt_len];
uint8_t tag[16]; // 128-bit tag
uint8_t decrypted[pt_len + 1];
// 4. Initialize AES Context
aes_context_t ctx;
aes_key_setup(&ctx, key, sizeof(key));
aes_gcm_encrypt(&ctx, iv, sizeof(iv), aad, aad_len, pt, pt_len, ct, tag, sizeof(tag));
int res = aes_gcm_decrypt(&ctx, iv, sizeof(iv), aad, aad_len, ct, pt_len, tag, sizeof(tag), decrypted);

11:05:12 System --- AES-GCM Encryption ---

11:05:12 Plaintext Secret Message: The eagle has landed.

11:05:12 Cipher D9C6C354CF0E6F5623782EBC1C78B31F5948A571BA780D182BFF6C10CDA9099EC334A422EF

11:05:12 Tag 8AA1C657B41B034526775E0CBED5A5DF

11:05:13 System --- AES-GCM Decryption ---

11:05:13 Decrypted Secret Message: The eagle has landed.

Hash

Hashing algorithms

BLAKE3

Implementation of Blake3

Keccak

Keccak that powers SHA3

Md5

Basic MD5 implementation

SM3

Chinese Hash

SHA1

SHA1 software implementation.

SHA2

SHA2 software implementation.

SHA3

SHA3 software implementation.

SHAKE

SHAKE software implementation

Example shake

int main() {
    printf("\n--- SHAKE256 Example ---\n");
    const char *shake_input = "Seychelles and Bonaire have beautiful beaches.";
    uint8_t shake_output[64]; // 512 bits output
    
    shake256(shake_output, sizeof(shake_output), shake_input, strlen(shake_input));
    printf("Input: %s\n", shake_input);
    print_hex("SHAKE256 Output (64 bytes)", shake_output, sizeof(shake_output));
    return 0;
}

07:45:12 System --- SHAKE256 XOF Hashing ---

07:45:12 Input Seychelles has beautiful beaches.

07:45:12 Params Length: 64 bytes (512 bits)

07:45:13 Hash B3A073A5658357FFCE7F5C2DF42D778642A90FF194DB1E2EEEF19BD433C59199AF608704BAC673CDF9A4422A57DEEDCBF2B9AF2753762FE8B7589B0A938DF07E

ECC

Eliptic curve cryptography

P224

NIST secp224r1

P256

NIST secp256r1

P384

NIST secp384r1

P521

NIST secp521r1

Curve25519

Software Implementation of DJB curve

ED/X25519

ECDH & EdDSA for Curve 25519

Curve448

Software Implementation of MH Curve

ED/X448

ECDH & EdDSA for Curve 448

Example secp381r1

    uint8_t private_key[48];
    uint8_t public_key[96];
    uint8_t signature[96];
    uint8_t msg_hash[48];
    p384_generate_random(msg_hash, sizeof(msg_hash));
    p384_gen_keypair(private_key, public_key);
    p384_ecdsa_sign(signature, private_key, msg_hash, sizeof(msg_hash));
    p384_ecdsa_verify(signature, public_key, msg_hash, sizeof(msg_hash));

10:04:12 System --- P-384 Minimal Example ---

10:04:12 ECDSA Keypair generated.

10:04:12 Private 7ec46c166d556bd65f4f20955a53293e2cdc4788813f6045f61c18fb4d562fc7ab5d0d53a0a9c6e2b8d9bdf124077015

10:04:12 Public 234ccf2e85387e087d5e87b20f0001292ceca6c3aa983a9d05783386baa0c442deb61a6d018713b14d403146a34fdf478d0226917626b316de9997b6de19de5d2a9c8163e41187804e47c556c5bfdfe6ab300deac35fa7f72f88d32b18a51a5b

10:04:13 Sign Signature created.

10:04:13 Hash 081ae5c1da33e90284964b11b42b5965224ab781f1226c63a343fce98ec06d7000300f0445294b5616a2d7090cde6a4d

10:04:13 Verify Signature verified.

MAC

Message Authentication Code

GHASH

achieved 2x improvcement over openSSL using Kurdi & Möller 2025 paper on arm64.

HMAC

Support for SHA1, SHA2-256, SHA2-384, SHA2-512,

POLY

Software implementation of Poly1305 only.

VMAC

Fast software implementation of VMAC.

Example HMAC-SHA512

int main()
{
    const char *key = "secret-key";
    const char *msg = "Hello, world!";
    uint8_t mac[SHA512_DIGEST_SIZE];
    hmac_sha512(key, strlen(key), msg, strlen(msg), mac);
    return 0;
}

12:45:01 Module --- HMAC-SHA512 Example ---

12:45:01 Secret Key: secret-key

12:45:01 Input Msg: Hello, world!

12:45:02 Output HMAC: 748647ebeeeaebede1f627e0137c314c58f387e52f4336581c749dcd34888f60c790c8e1669493dd171aaf898c7e68ffebb774d06e60ef30c3ab482eafe984f2

Ghash performance : Kurdi & Möller November 2025

BENCH Config GHASH | Buffer: 256 MB | Iterations: 200 | Total: 50.00 GB

14:20:01 Radikant Time: 3.6511s | Throughput: 13.69 GB/s

14:20:05 OpenSSL Time: 6.7905s | Throughput: 7.36 GB/s

KDF

Key Derivation Functions

Argon2

Argon2 with Blake2

HKDF

HMAC-based Extract-and-Expand Key Derivation Function

PBKDF2

Password-Based Key Derivation Function 2

SCRYPT

Scrypt

Example PBKDF2

int main()
{
    const char *password = "password";
    const uint8_t salt[] = { 0x12, 0x34, 0x56, 0x78 };
    uint32_t iterations = 4096;
    uint8_t dk[64];
    printf("--- PBKDF2-HMAC-SHA512 Example ---\n");
    pbkdf2_hmac_sha512((const uint8_t*)password, strlen(password),
                       salt, sizeof(salt),
                       iterations, dk, sizeof(dk));
    printf("Password: %s\n", password);
    print_hex("Salt", salt, sizeof(salt));
    printf("Iterations: %d\n", iterations);
    print_hex("Derived Key", dk, sizeof(dk));
    return 0;
}

14:20:10 Config --- PBKDF2-HMAC-SHA512 Example ---

14:20:10 Secret Password: password

14:20:10 Params Salt: 12345678 | Iterations: 4096

14:20:11 Derived 33320e9d66500d5b6021d717da567732f323a8775b39fcef4f83f75fe34441592b72c82cb97068ad5a6b72a71b0487d8bcaab379962c165c8e795bce83c6d435

Testing

In order to test the bit output of this library the build can produce seperate testing binaries specific for testing against rfc vectors. Since alot of cryptographic primitives are build ontop of eachother a very simple and rudimentary test setup is used for regression testing. Radikant probe is utilized for quick testing and Radikant Log for logging. The most commonly used primitives are now tested, but quite a few ciphers like SM2, Grashopper and many more havent been fully tested on correct output, but appear functional at first glance. One of the first next great improvements would be to focus on memory and constant time for major primitives.

Radikant Probe Output

 FINAL SUMMARY REPORT | Radikant ECC X25519 Suite | RFC 7748                    
|------------------------------------------------------------------------------|
| S | M | Ψ | ID   | Status | Name                           | Standard        |
|---+---+---+------+--------+--------------------------------+-----------------|
| ✓ | ✗ | ✓ | 0    | PASS   | test_arithmetic_fuzz           | Arithmetic Fuzz |
| ✓ | ✗ | ✓ | 1    | PASS   | test_rfc7748_vectors           | RFC 7748 Vector |
| ✓ | ✗ | ✓ | 2    | PASS   | test_properties                | Properties      |
| ✓ | ✗ | ✓ | 3    | PASS   | test_edge_cases                | Edge Cases      |
| ✓ | ✗ | ✓ | 4    | PASS   | test_clamping_safety           | Clamping Safety |
| ✓ | ✓ | ✓ | 5    | PASS   | test_monte_carlo_1k            | Monte Carlo 1k  |
| ✓ | ✓ | ✓ | 6    | PASS   | test_monte_carlo_1m            | Monte Carlo 1M  |
================================================================================
 SUMMARY: 7 Tests Run | 7 Passed | 0 Failed
================================================================================