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Ruby

Duplicate openssl dgst -sha256 -sign private.pem -out sha256.sig in.dat

See more OpenSSL Examples

Demonstrates how to duplicate this OpenSSL command:
openssl dgst -sha256 -sign private.pem -out sha256.sig in.dat
The in.dat file can contain text or binary data of any type. The OpenSSL command does the following:
  1. Creates a SHA256 digest of the contents of the input file
  2. Signs the SHA256 digest using the private 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.

pkey = Chilkat::CkPrivateKey.new()

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

rsa = Chilkat::CkRsa.new()

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

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

# Load the file to be signed.
bdFileData = Chilkat::CkBinData.new()
success = bdFileData.LoadFile("in.dat")

bdSig = Chilkat::CkBinData.new()
success = rsa.SignBd(bdFileData,"sha256",bdSig)
if (success == false)
    print rsa.lastErrorText() + "\n";
    exit
end

# Save the binary signature to a file.
success = bdSig.WriteFile("signature.sig")
if (success != true)
    print "Failed to write signature.sig." + "\n";
    exit
end

print "Success." + "\n";