- known_hosts: the @cert-authority pattern matcher was recursive and
backtracking; a pattern of a few hundred thousand stars overflowed the
connect thread's stack on every handshake and '*a*a*a…b' went
exponential. It is now the iterative two-pointer match, and patterns
over 1 KiB are refused on import and in Trust a CA.
- Agent-forward and remote-forward channels are only honoured on the
final hop: a jump host could previously open auth-agent channels and
reach remote-forward destinations on the client machine.
- Remote forwards with no bind address listen on the server's loopback
(as ssh -R does) instead of every interface.
- Keyboard-interactive gives up after 10 rounds; dials through jump hosts
and run_command have timeouts; the handshake timeout leaves room for
the host-key prompt so a slow reader isn't timed out mid-decision.
- Known hosts are looked up per key type, so an imported known_hosts with
ed25519 and RSA rows no longer produces a false 'key changed' warning.
- SFTP download suggests a sanitised base name in the save dialog.
Andy Dixon
0bcfe6470b