Lua Requires Chilkat v11.0.0+

Get EC Public Key from EC Private Key

See more ECC Examples

Demonstrates how to get an EC public key from an EC private key. Lua

local chilkat = require("chilkat")

-- We have an ECC private key...
-- The contents of the private key PEM file look like this:

--     -----BEGIN PRIVATE KEY-----
--     MIGHAgEAMBMGByqGSM49AgEGCCqGSM49AwEHBG0wawIBAQQg3J8q/24D1sEKGdP9
--     72MGYElLGpw/a56Y3t6pfON3uhShRANCAATlSmoizyhAwoYZAOuFBATl07/1RR54
--     a1Dzfm16grxJe666AGKR+bSs24hk7TEpaeCTvT8YOOM3l+xKFg7zq6Q9
--     -----END PRIVATE KEY-----

local privKey = chilkat.PrivateKey.new()
local success = privKey:load_pem_file("qa_data/ecc/secp256r1-key-pkcs8.pem")
if not success then
    print(privKey.last_error_text)
    return
end

-- Get the public key.
local pubKey = chilkat.PublicKey.new()
privKey:to_public_key(pubKey)

-- Save the public key to a PEM file.
success = pubKey:save_pem_file(false, "qa_data/ecc/secp256r1-pubkey.pem")
if not success then
    print(pubKey.last_error_text)
    return
end

-- The contents of the ECC public key PEM file look like this:

--     -----BEGIN PUBLIC KEY-----
--     MIIBSzCCAQMGByqGSM49AgEwgfcCAQEwLAYHKoZIzj0BAQIhAP////8AAAABAAAA
--     AAAAAAAAAAAA////////////////MFsEIP////8AAAABAAAAAAAAAAAAAAAA////
--     ///////////8BCBaxjXYqjqT57PrvVV2mIa8ZR0GsMxTsPY7zjw+J9JgSwMVAMSd
--     NgiG5wSTamZ44ROdJreBn36QBEEEaxfR8uEsQkf4vOblY6RA8ncDfYEt6zOg9KE5
--     RdiYwpZP40Li/hp/m47n60p8D54WK84zV2sxXs7LtkBoN79R9QIhAP////8AAAAA
--     //////////+85vqtpxeehPO5ysL8YyVRAgEBA0IABOVKaiLPKEDChhkA64UEBOXT
--     v/VFHnhrUPN+bXqCvEl7rroAYpH5tKzbiGTtMSlp4JO9Pxg44zeX7EoWDvOrpD0=
--     -----END PUBLIC KEY-----

print("Success.")