Add support for bad ssh servers

[amphp]

Add support for bad ssh servers

[kelunik]

Do you know which versions are affected?

[Ekstazi]

From https://www.openssh.com/releasenotes.html

Changes since OpenSSH 7.4

Fix various fallout and sharp edges caused by removing SSH protocol 1 support from the server, including the server banner string being incorrectly terminated with only \n (instead of \r\n), confusing
error messages from ssh-keyscan bz#2583 and a segfault in sshd
if protocol v.1 was enabled for the client and sshd_config contained references to legacy keys bz#2686.

[kelunik]

Thanks, so the first fixed version is OpenSSH 7.5/7.5p1 (2017-03-20), which is more recent than I expected. I guess it's fine to fix then. Do you want to send a PR?

[Ekstazi]

yes. I'll do it.

[kelunik]

Thanks! I've fixed the comment and pushed another commit avoiding an infinite loop if the connection breaks during the read.