easy:SetOpt_CRLFile(file)
file with the
concatenation of CRL (in PEM format) to use in the certificate validation that
occurs during the SSL exchange.
When curl is built to use NSS or GnuTLS, there is no way to influence the use
of CRL passed to help in the verification process. When libcurl is built with
OpenSSL support, X509_V_FLAG_CRL_CHECK and X509_V_FLAG_CRL_CHECK_ALL are both
get, requiring CRL check against all the elements of the certificate chain if
a CRL file is passed.
This option makes sense only when used in combination with the
#CURLOPT_SSL_VERIFYPEER option.
A specific error code (#CURLE_SSL_CRL_BADFILE) is defined with the
option. It is returned when the SSL exchange fails because the CRL file cannot
be loaded. A failure in certificate verification due to a revocation
information found in the CRL does not trigger this specific error.