How to verify a ECC signature with OpenSSL command?

Question

I have a public key, a 192 bit hash, and a 384 bit signature, all as .txt hex files, and the curve is prime192v1.

What command lines can I use to verify the message with OpenSSL?

Answer 1

For reference, the EC key can be created with the following command:

• Create the EC key:

  $ openssl ecparam -genkey -name prime192v1 > key.pem
  

• Extract the public key:

  $ openssl ec -in key.pem -pubout > pub.pem
  

Signing the hash of a message and verifying the signature with an EC key can be done the same way as with other key types:

• Calculate the hash (use a hash funtion of your choice):

  $ openssl dgst -sha256 -binary message.txt > hash.txt
  

• Sign the hash with the private key:

   $ openssl pkeyutl -sign -inkey key.pem -in hash.txt > sig.txt
  

• Verify the signature with the public key:

   $ openssl pkeyutl -verify -in hash.txt -sigfile sig.txt -inkey pub.pem -pubin
   Signature Verified Successfully