Make sure options->ciphername and options->authname are always defined

Make sure options->ciphername and options->authname are always defined

The NCP code does a strcmp(options->ciphername, ...) without first checking
whether options->ciphername is NULL.  This could cause a crash when using
"--cipher none".  This patch fixes that problem by ensuring that
options->ciphername (and options->authname) are never NULL.  Ensuring that
options->ciphername is never null prevents us from having to write null
checks everywhere.

Signed-off-by: Steffan Karger <steffan@karger.me>
Acked-by: Arne Schwabe <arne@rfc2549.org>
Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <1475055231-1778-1-git-send-email-steffan@karger.me>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg12576.html

Signed-off-by: Gert Doering <gert@greenie.muc.de>