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Ruby

Duplicate openssl dgst -sha256 -verify pubKey.pem -signature signature.sig in.dat

See more OpenSSL Examples

Demonstrates how to duplicate this OpenSSL command:
openssl dgst -sha256 -verify pubKey.pem -signature signature.sig in.dat
The in.dat file contains the original data that was signed, and can contain text or binary data of any type. The above OpenSSL command does the following:
  1. Creates a SHA256 digest of the contents of the input file.
  2. Verifies the SHA256 digest using the public key.

Chilkat Ruby Downloads

Ruby
require 'chilkat'

success = false

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

pubKey = Chilkat::CkPublicKey.new()

# Load the public key from an PEM file:
success = pubKey.LoadFromFile("pubKey.pem")
if (success == false)
    print pubKey.lastErrorText() + "\n";
    exit
end

# Load the data of the original file that was signed.
bdFileData = Chilkat::CkBinData.new()
success = bdFileData.LoadFile("in.dat")

# Load the signature.
bdSig = Chilkat::CkBinData.new()
success = bdSig.LoadFile("signature.sig")

rsa = Chilkat::CkRsa.new()

# Import the public key into the RSA component:
success = rsa.UsePublicKey(pubKey)
if (success == false)
    print rsa.lastErrorText() + "\n";
    exit
end

# OpenSSL uses big-endian.
rsa.put_LittleEndian(false)

success = rsa.VerifyBd(bdFileData,"sha256",bdSig)
if (success != true)
    print rsa.lastErrorText() + "\n";
    print "The signature was invalid." + "\n";
    exit
end

print "The signature was verified." + "\n";