verifying a file signature with openssl dgst

Question

I am trying to verify a signature for a file:

openssl dgst -verify cert.pem -signature file.sha1 file.data

• all it says is "unable to load key file"

The certificate says:

openssl verify cert.pem 

cert.pem: /C=....
error 20 at 0 depth lookup:unable to get local issuer certificate

However, I specifically don't care about verifying the certificate, I want only to verify the signature for a given file!

Answer 1

The answer is here: http://stackoverflow.com/questions/2385320/verifying-a-file-signature-with-openssl-dgst