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Lua Requires Chilkat v11.0.0+

RSA Sign with PKCS8 Encrypted Key

See more RSA Examples

Demonstrates how to load a private key from an encrypted PKCS8 file and create an RSA digital signature.

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Lua
local chilkat = require("chilkat")

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

local pkey = chilkat.PrivateKey.new()

-- Load the private key from an RSA PEM file:
local success = pkey:load_pkcs8_encrypted_file("privateKey.key", "myPassword")

local rsa = chilkat.Rsa.new()

-- Import the private key into the RSA object:
success = rsa:use_private_key(pkey)
if not success then
    print(rsa.last_error_text)
    return
end

-- Return the signature in hex
rsa.encoding_mode = "hex"

local strData = "This is the string to be signed."

-- Sign the string using the sha-1 hash algorithm.
-- Other valid choices are "md2", "sha256", "sha384", "sha512",  and "md5".
local hexSig = rsa:sign_string_enc(strData, "sha-1")

print(hexSig)