pub const CHACHA20_IETF_MAX_LEN: u64 = _ /* 274_877_906_816u64 */;Expand description
Maximum number of bytes that may be encrypted under a single (key, nonce) pair with the
IETF (RFC 8439) layout.
RFC 8439 Section 2.8 caps the IETF variant at 2^32 - 1 blocks of 64 bytes because the block
counter is 32 bits wide. This constant keeps one block of margin (2^32 - 2 blocks) so the
counter can never wrap and reuse keystream.
Exceeding this limit makes the ChaCha20-Poly1305 / XChaCha20-Poly1305 / ChaCha8-Poly1305 AEADs
panic on encryption and return AeadError::InvalidCiphertext on decryption,
and makes StreamCipher::xor_keystream panic.