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cryptographyopenssldigital-signatureecdsa

OpenSSL ECDSA sign and verify file

I would like to sign and verify a pdf with elliptic curve. I got some code but it doesn't work.

Create private key:

openssl ecparam -genkey -name secp384r1 -noout -out private.pem

Create public key:

openssl ec -in private.pem -pubout -out public.pem

Sign file:

openssl dgst -ecdsa-with-SHA1 test.pdf > hash openssl dgst
openssl dgst -ecdsa-with-SHA1 -inkey private.pem -keyform PEM -in hash > signature

Verify file:

openssl dgst -ecdsa-with-SHA1 -verify public.pem -signature signature.bin data

The part to sign and verify doesn't work.

Solution

  • I'm not sure where you're getting these command line options from - the help for dgst doesn't indicate that -ecdsa-with-SHA1, -inkey or -in are valid options. Try:

    Sign:

    openssl dgst -sha1 -sign private.pem < test.pdf > signature.bin

    Verify:

    openssl dgst -sha1 -verify public.pem -signature signature.bin < test.pdf