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Lua Requires Chilkat v11.0.0+

Generate an ECC Key (Public and Private)

See more ECC Examples

Demonstrates how to generate an ECC key and save both public and private parts.

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Lua
local chilkat = require("chilkat")

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

-- Create a Fortuna PRNG and seed it with system entropy.
-- This will be our source of random data for generating the ECC private key.
local fortuna = chilkat.Prng.new()
local entropy = fortuna:get_entropy(32, "base64")
local success = fortuna:add_entropy(entropy, "base64")

local ecc = chilkat.Ecc.new()

-- Generate a random ECC private key on the secp256r1 curve.
-- Chilkat also supports other curves, such as secp384r1, secp521r1, and secp256k1.

local privKey = chilkat.PrivateKey.new()
success = ecc:gen_key("secp256r1", fortuna, privKey)
if not success then
    print(ecc.last_error_text)
    return
end

-- Save the private key to PKCS8 encrypted PEM
-- (The private key can be saved in a variety of different formats. See the online reference documentation.)
success = privKey:save_pkcs8_encrypted_pem_file("pemPassword", "qa_output/eccPrivKey.pem")
if not success then
    print(privKey.last_error_text)
end

-- The private key PEM looks like this:

--     -----BEGIN ENCRYPTED PRIVATE KEY-----
--     MIHFMEAGCSqGSIb3DQEFDTAzMBsGCSqGSIb3DQEFDDAOBAhUmn+1/lwCIwICCAAw
--     FAYIKoZIhvcNAwcECPlyNXAXZO+oBIGAIvxvTENXJWbrCwSjh0QNxLecBotUpfI5
--     auOonLmwVMyt1ahMmNyVo/D+pnKQSE41Fg8fApM0DCDKZUOVCCcK1qirIsMPQkGp
--     klPJbvrQRVYgzBtU31uNB5y2wqhrIeepal1HXBvbkUK0nfJMbcdz/XAEIQu2HhTD
--     t6LMScPQld4=
--     -----END ENCRYPTED PRIVATE KEY-----

-- Now get the public key part from the private key.
-- (A public key is actually a subset of the private key.)
local pubKey = chilkat.PublicKey.new()
privKey:to_public_key(pubKey)

-- Save the public key to a PEM file.
-- (The public key can be saved in a variety of different formats. See the online reference documentation.)
-- For ECC keys, the 1st argument (bPreferPkcs1) is ignored and unused.
local bPreferPkcs1 = false
success = pubKey:save_pem_file(bPreferPkcs1, "qa_output/eccPubKey.pem")

-- The public key PEM looks like this:

--     -----BEGIN PUBLIC KEY-----
--     MIIBSzCCAQMGByqGSM49AgEwgfcCAQEwLAYHKoZIzj0BAQIhAP////8AAAABAAAA
--     AAAAAAAAAAAA////////////////MFsEIP////8AAAABAAAAAAAAAAAAAAAA////
--     ///////////8BCBaxjXYqjqT57PrvVV2mIa8ZR0GsMxTsPY7zjw+J9JgSwMVAMSd
--     NgiG5wSTamZ44ROdJreBn36QBEEEaxfR8uEsQkf4vOblY6RA8ncDfYEt6zOg9KE5
--     RdiYwpZP40Li/hp/m47n60p8D54WK84zV2sxXs7LtkBoN79R9QIhAP////8AAAAA
--     //////////+85vqtpxeehPO5ysL8YyVRAgEBA0IABGdOH8uM6SfX3mdV+TR0mWp2
--     gfVRPlxWxwhOiowuNByBxmQz7ZR4CJY1XcN2zkUo5pzW73ZhGwgd2XTOvqPqG40=
--     -----END PUBLIC KEY-----
--

print("finished.")