decoder_results.json

#!/usr/bin/env python3
"""
basic_kem.py — Basic RCLP-KEM round-trip example.

Demonstrates key generation, encapsulation, and decapsulation
for the RCLP-128 parameter set.
"""

import sys
from pathlib import Path
sys.path.insert(0, str(Path(__file__).parent.parent / "src"))

from rclp import RCLP_KEM


def main():
    print("RCLP-KEM Basic Example")
    print("=" * 40)

    # Initialize with 128-bit security
    kem = RCLP_KEM(security_bits=128)
    print(f"Parameter set: RCLP-{kem.security_bits}")
    print(f"  Layers: {kem.n_layers}")
    print(f"  Public key: {kem.public_key_size()} bytes")
    print(f"  Secret key: {kem.secret_key_size()} bytes")
    print(f"  Ciphertext: {kem.ciphertext_size()} bytes")

    # Key generation
    print("\n[1] Generating keypair...")
    pk, sk = kem.keygen()
    print("    Done.")

    # Encapsulation (sender side)
    print("[2] Encapsulating shared secret...")
    ct, ss_sender = kem.encapsulate(pk)
    print(f"    Shared secret (sender): {ss_sender[:16].hex()}...")

    # Decapsulation (receiver side)
    print("[3] Decapsulating shared secret...")
    ss_receiver = kem.decapsulate(sk, ct)
    print(f"    Shared secret (receiver): {ss_receiver[:16].hex()}...")

    # Verify
    match = ss_sender == ss_receiver
    print(f"\n{'✓' if match else '✗'} Shared secrets {'match' if match else 'DO NOT match'}!")

    if match:
        print("\nThe 32-byte shared secret can now be used as a symmetric key")
        print("for AES-256-GCM or ChaCha20-Poly1305.")


if __name__ == "__main__":
    main()