ChaCha20 Encryption

ChaCha20 is a modern stream cipher designed by Daniel J. Bernstein, known for its high performance and security.

Key Generation

Generate a secure key and nonce for ChaCha20 encryption

Encrypt File

Upload a file and encrypt it with ChaCha20

Decrypt File

Upload an encrypted file and decrypt it with ChaCha20

About ChaCha20 Encryption

ChaCha20 is a modern stream cipher designed by Daniel J. Bernstein in 2008. It's an evolution of the Salsa20 cipher, with improved diffusion and resistance against certain attacks.

  • ChaCha20 uses a 256-bit key and a 96-bit nonce (number used once).
  • It's a stream cipher that generates a keystream which is XORed with the plaintext to produce ciphertext.
  • ChaCha20 is designed to be highly resistant to timing attacks and other side-channel attacks.
  • It's particularly efficient in software implementations, especially on CPUs without dedicated AES instructions.
Key Features:
  • Performance: ChaCha20 is extremely fast in software, often outperforming AES on platforms without hardware acceleration.
  • Security: No practical attacks have been found against ChaCha20 with its full 20 rounds.
  • Simplicity: The algorithm is relatively simple, making it easier to implement correctly and audit.
  • Constant-time operation: ChaCha20 operations take the same amount of time regardless of the data being processed, which helps prevent timing attacks.
Modern Usage:

ChaCha20 is often used in combination with the Poly1305 message authentication code, forming the ChaCha20-Poly1305 authenticated encryption scheme. This combination is used in several important protocols:

  • TLS 1.3 includes ChaCha20-Poly1305 as a mandatory-to-implement cipher suite.
  • It's used in WireGuard VPN protocol.
  • Signal Protocol uses ChaCha20 for its encrypted messaging.
  • SSH implementations often support ChaCha20-Poly1305.
Note: ChaCha20, like all stream ciphers, should never reuse the same key and nonce combination. Doing so would completely compromise security. Always use a fresh nonce for each encryption operation with the same key.