These tests try to ensure better compatibility of our server implementation with the ssh CLI. With these tests in place: 1) before merging CL 447757 we would have noticed that our server implementation was broken with OpenSSH 8.8+ 2) after merging CL 447757 we would have noticed that our server implementation was broken with OpenSSH 7.2-7.7 The ssh CLI from $PATH is used by default, but can be overridden using the SSH_CLI_PATH environment variable. Change-Id: I93d64be41c7613132b0364afac8397f57c2dcbca Reviewed-on: https://go-review.googlesource.com/c/crypto/+/506837 TryBot-Result: Gopher Robot <gobot@golang.org> Reviewed-by: Benny Siegert <bsiegert@gmail.com> Reviewed-by: Han-Wen Nienhuys <hanwen@google.com> Run-TryBot: Nicola Murino <nicola.murino@gmail.com>