//! User authentication — RFC 4252 (with RFC 4256 keyboard-interactive).
//!
//! The transport layer first carries a `SSH_MSG_SERVICE_REQUEST` for
//! `"ssh-userauth"`; once accepted, the peer sends `SSH_MSG_USERAUTH_REQUEST`
//! messages whose `method` field selects one of:
//!
//! - `"none"` — probe to learn allowed methods
//! - `"password"` — RFC 4252 §8
//! - `"publickey"` — RFC 4252 §7
//! - `"keyboard-interactive"` — RFC 4256
//! - `"hostbased"` — RFC 4252 §9 (not implemented here)
//!
//! Everything in this module is sans-I/O: state machines consume and produce
//! SSH *payload* bytes (the message-type byte plus method-specific fields)
//! and never touch sockets directly.
pub use ;
pub use ;