Lua Requires Chilkat v11.0.0+

Working with PEM Encrypted Private Keys

See more PEM Examples

Demonstrates how to load and save PEM encrypted private keys. Lua

local chilkat = require("chilkat")

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

local success = false

local pem = chilkat.Pem.new()

local pemPassword = "secret"

-- To load a PEM file containing encrypted private keys, simply
-- provide the password.
success = pem:load_pem_file("/Users/chilkat/testData/pem/pemContainingEncryptedPrivateKeys.pem", pemPassword)
if not success then
    print(pem.last_error_text)
    return
end

local fac = chilkat.FileAccess.new()
local pemText = fac:read_entire_text_file("/Users/chilkat/testData/pem/pemContainingEncryptedPrivateKeys.pem", "utf-8")

-- To load a PEM from a string, call LoadPem instead of LoadPemFile:
success = pem:load_pem(pemText, pemPassword)
if not success then
    print(pem.last_error_text)
    return
end

-- A few notes:
-- The PEM may contain both private keys and certificates (or anything else).
-- The password is utilized for whatever content in the PEM is encrypted.
-- It is OK to have both encrypted and non-encrypted content within a given PEM.

-- PEM private keys can be encrypted in different formats.  The LoadPem and LoadPemFile
-- methods automatically handle the different formats.
-- One format is PKCS8 and is indicated by this delimiter within the PEM:

-- -----BEGIN ENCRYPTED PRIVATE KEY-----
-- MIICoTAbBgkqhkiG9w0BBQMwDgQIfdD0zv24lgkCAggABIICgE0PdHJmRbNs6cBX
-- ...

-- Another format, we'll call "passphrase" looks like this in the PEM:
-- -----BEGIN RSA PRIVATE KEY-----
-- Proc-Type: 4,ENCRYPTED
-- DEK-Info: DES-EDE3-CBC,A4215544D11C5D0C
--
-- paqy9XRexcSjurHfG0xhCaUD0HrvIdhuC0CbRxxxeMlkLaV6+uT80rBxt2AaibWG
-- ...

-- Show the bit length of each private key:
local numPrivateKeys = pem.num_private_keys
if numPrivateKeys == 0 then
    print("Error: Expected the PEM to contain private keys.")
    return
end

local privKey = chilkat.PrivateKey.new()
for i = 1, numPrivateKeys do
    pem:private_key_at(i - 1, privKey)
    print(i .. ": " .. privKey.bit_length .. " bits")
end