If hostname verification fails, store_context.error is V_OK

[joshcooper]

#60 enabled hostname verification by default, as many applications using SSLSockets directly don't know or remember to call post_connection_check.

One unexpected outcome is if an application implements a verify_callback and verification fails, then it is called with preverify_ok=false, but the store_context.error=0 which is OpenSSL::X509::V_OK! This could cause problems if an application assumes store_context.error == 0 means verification succeeded.

If a hostname mismatch is detected, I would expect store_context.error to be set to OpenSSL::X509::V_ERR_CERT_REJECTED so that there is no chance of confusion.

[joshcooper]

Thanks @rhenium!