checkcert version 1.00 usage: 

   checkcert [-kemihvV] [-f /path/to/cert] www.domain.com

    See if a digital certificate has expired and optionally see
    if the certificate properly matches its private key by comparing 
    the modulus block and exponent fields. This program outputs
    nothing if all is well and verbose mode is turned off.

 where:

    -k         Check cert against private key 
    -e         Display Exponent field
    -m         Display Modulus block

    -i         Display Certficate issuer
    -f         Use specific cert file to check, not default file
    -h         Display this help
    -v         Verbose mode, show expiration date
    -V         Show really verbose mode (contents of cert and key)

Files Used:

    On Cobalt Raqs the SSL files are kept in separate directories for
    each virtual domain. The certificates, keys and csr's are stored 
    in the /home/sites/www.domain.com/certs directory.

Examples:

    checkcert -v www.yahoo.com

    Certificate Starts:  Apr 24 08:57:08 2001 GMT
    Certificate Expires: May  1 22:53:49 2002 GMT

    checkcert -ek www.domain.com

    Cert Exponent: 65537 (0x10001)
    Key  Exponent: 65537 (0x10001)
    Error: Certificate does not match private key for www.domain.com