A command-line implementation of the Elgamal public-key cryptosystem using elliptic curves. Uses 2048-bit primes that are congruent to 3 modulo 4. Divides the plaintext into blocks of 128 characters. Converts each block to an integer by interpreting the ASCII encodings of the characters in the block as the base-256 digits of the integer.
To generate your public and private keys, run python3 GenerateKeys.py. This will save the keys in my_elgamal_public_key.txt
and my_elgamal_private_key.txt.
To encrypt your plaintext, have your plaintext file saved as plaintext.txt in the same directory. Run python3 Encryption.py,
and the ciphertext will be saved to elgamal_encrypted_message.txt.
To decrypt some ciphertext, run python3 Decryption.py. The decrypted plaintext will be saved to elgamal_decrypted_message.txt.