Safe cookie authentication failure replies do not end with a CRLF
On the control socket, AUTHCHALLENGE's failure replies do not end with a CRLF.
+12:29% nc localhost 9100 AUTHCHALLENGE SAFEOHJOIE 513 AUTHCHALLENGE only supports SAFECOOKIE authentication%
+1:43% nc localhost 9100 AUTHCHALLENGE SAFECOOKIE FOOFA 513 Invalid base16 client nonce%
That is all.
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