(PHP 4 >= 4.0.6, PHP 5, PHP 7)
openssl_x509_parse — Parse an X509 certificate and return the information as an array
openssl_x509_parse() returns information about the
supplied x509cert, including fields such as subject
name, issuer name, purposes, valid from and valid to dates etc.
x509cert
shortnames
shortnames controls how the data is indexed in the
array - if shortnames is TRUE (the default) then
fields will be indexed with the short name form, otherwise, the long name
form will be used - e.g.: CN is the shortname form of commonName.
The structure of the returned data is (deliberately) not yet documented, as it is still subject to change.