Security

This document outlines the cryptographic methods used in the RelaySMS Vault. All cryptographic operations are defined in the crypto.py file.

Cryptographic Methods

AES Encryption

Advanced Encryption Standard (AES) is used for secure data storage.

• Key Size: 256 bits (32 bytes)
• Mode of Operation: AES-EAX
• Purpose: Encrypts and decrypts data at rest.
• Reference: NIST AES Specification

HMAC for Integrity Verification

Hash-based Message Authentication Code (HMAC) ensures data integrity.

• Algorithm: SHA-512
• Key Size: 256 bits (32 bytes)
• Purpose: Verifies data authenticity.
• Reference: RFC 2104 - HMAC

Fernet Encryption

Fernet encryption is used for token encryption.

• Key Size: 256 bits (32 bytes)
• Purpose: Encrypts and decrypts identity tokens.
• Reference: Fernet Cryptography Documentation

Message Encryption

Signal Double Ratchet Algorithm encrypts and decrypts messages.

• Key Exchange: X25519 public key exchange.
• Algorithm: Double Ratchet for message encryption.
• Purpose: Secures message transmission.
• Reference: Signal Protocol Documentation