Lua

Create PKCS7 (CMS) EnvelopedData

Encrypt some data to a recipient by creating a PKCS7 (CMS) EnvelopedData structure. The data will be encrypted using a symmetric content-encryption algorithm (e.g., AES), and the randomly generated symmetric key will be encrypted using the recipient’s RSA public key extracted from their X.509 certificate. Lua

local chilkat = require("chilkat")

local crypt = chilkat.Crypt2.new()

-- Specify the encryption to be used.
-- "pki" indicates "Public Key Infrastructure" and will create a PKCS7 encrypted (enveloped-data) message.
crypt.crypt_algorithm = "pki"
crypt.pkcs7_crypt_alg = "aes"
crypt.key_length = 256
crypt.oaep_hash = "sha256"
crypt.oaep_padding = true

local cert = chilkat.Cert.new()

-- Use a certificate found in the Windows certificate store.
local success = cert:load_by_common_name("My Certificate")
if not success then
    print(cert.last_error_text)
    return
end

-- Tell the crypt object to use the certificate.
crypt:set_encrypt_cert(cert)

local toBeEncrypted = "This string is to be encrypted."

-- Get the result in multi-line BASE64 MIME format.
crypt.encoding_mode = "base64_mime"
crypt.charset = "utf-8"

local result = crypt:encrypt_string_enc(toBeEncrypted)
if not success then
    print(crypt.last_error_text)
    return
end

-- -------------------------------------------------------------------------
-- See the following example to decrypt what was created in this example
-- Decrypt PKCS7 (CMS) EnvelopedData
-- -------------------------------------------------------------------------

print(result)

-- Sample output:

-- MIICSgYJKoZIhvcNAQcDoIICOzCCAjcCAQAxggHiMIIB3gIBADCBljCBgTELMAkGA1UEBhMCSVQx
-- EDAOBgNVBAgMB0JlcmdhbW8xGTAXBgNVBAcMEFBvbnRlIFNhbiBQaWV0cm8xFzAVBgNVBAoMDkFj
-- dGFsaXMgUy5wLkEuMSwwKgYDVQQDDCNBY3RhbGlzIENsaWVudCBBdXRoZW50aWNhdGlvbiBDQSBH
-- MwIQPCWvkSv8oQ7xRmEHJ6TzEDA8BgkqhkiG9w0BAQcwL6APMA0GCWCGSAFlAwQCAQUAoRwwGgYJ
-- KoZIhvcNAQEIMA0GCWCGSAFlAwQCAQUABIIBAKqHAPQNSsQoX7B2NH7QyEOWQRsSVs8oCHXmy8f4
-- MVZD2er3bvYUCIomxpwbLEAl14qjUIMynahooYGgqip7+4FqL301G+BVjZVfEhHWj+VI1dAWnWuL
-- VHlvc/pbQNBWqV8rKVJsNIsuAZkdj4WSwLVKxYkYX43B8fh/g71XN2DTJu7Z/824v48KBmgpQBOT
-- 2q7IcDGxNPAFN2p6eavIVGn2LvhEbf/Fszyj+GR5tMcnQP1BOLJ3s3JzUBbvj8hcZrF1Vhl9HnTU
-- YQx8G/KdW1mR+Wlhl3BWoK0LYKRTbnTx2BXOs0CY1SXOAdhKr01ZYjA+xW4nGzY0lfXS9QZjh9gw
-- TAYJKoZIhvcNAQcBMB0GCWCGSAFlAwQBKgQQw0xTbfmnt0zjWHo5SaQIp4AgxTVY9E/Ncqy6t+RM
-- 8y4c3Av62/wB8IpPUEmtM2OeuZo=