Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/12907)
The B<s_client> utility is a test tool and is designed to continue the
handshake after any certificate verification errors. As a result it will
-accept any certificate chain (trusted or not) sent by the peer. None test
+accept any certificate chain (trusted or not) sent by the peer. Non-test
applications should B<not> do this as it makes them vulnerable to a MITM
attack. This behaviour can be changed by with the B<-verify_return_error>
option: any verify errors are then returned aborting the handshake.