I have a signed message created by openssl (openssl smime -sign ....). I
would like to verify the signature in the signed file step by step. (i
know that i can do verification process by the command openssl smime
-verify ..)
-first, i have do openssl asn1pase ... to take more information.
- second, i have compared the the octet string of the message digest,
which is seen when doing the first step, with the hash of the file, is
the same hash.
- third, i have taken the octet string of the signature and have
verified it by "openssl rsautl -verify " using the public key of the
signer. The latter command output is the identifier of the hash
algorithm and the message digest. This message digest is not the hash of
the file which is signed.
So, how can i deal with this problem.
signature verification step by step usin openssl.
-----BEGIN PKCS7-----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-----END PKCS7-----
