OpenSSL: explicitly set start/end date using `openssl req`?

Question

Using the openssl req tool, is it possible to explicitly specify the start and end dates on the certificate (eg, like the -startdate and -enddate options to openssl ca)?

I would like to create a certificate which is valid between a date in the past and a date in the future.

Answer 1

openssl req creates a certificate request (CSR), not a certificate. It's up to the CA to decide the notBefore and notAfter dates (like any other attributes it's willing to issue) when it creates the certificate. The CSR format (PKCS#10) doesn't have any fields to put these dates.

Of course, if it's for a self-signed certificate, you can issue the certificate from your own CSR with the dates you want, using openssl ca (or by changing the configuration in the OpenSSL configuration file).