SSLVerifyCNName sets the name which is used when verifying the hostname against the certificate presented by Duo's server. SSLVerifyCNScheme controls how the verification is done, for example, if wildcards are allowed. For more information, see IO::Socket::SSL .

The following allow wildcard certificate name *.duosecurity.com to match.

SSLVerifyCNName duosecurity.com
SSLVerifyCNScheme http