Extract public key from certificate in DER format

openssl certificate extract public-key der
marcolopes picture marcolopes · Nov 24, 2012 · Viewed 39k times · Source

I have a .cer certificate file, and need to extract the Public Key. I can only extract to PEM format. The "outform" parameter does nothing.

openssl x509 -inform PEM -in certificate.cer -outform DER -pubkey -noout > publickey.der

Is it possible to extract in DER format?

Answer

marcolopes picture marcolopes · Nov 24, 2012

Solved decoding the base64 PEM file:

openssl x509 -in certificate.cer -pubkey -noout | openssl enc -base64 -d > publickey.der

Any other idea is welcome.

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