(PHP Extension) Get ECC Public Key from ECC Private Key

Demonstrates how to get an ECC public key from an ECC private key.

Chilkat PHP Downloads PHP Extension for Windows, Linux, MacOS, Alpine Linux, Solaris

<?php

// The version number (9_5_0) should match version of the Chilkat extension used, omitting the micro-version number.
// For example, if using Chilkat v9.5.0.48, then include as shown here:
include("chilkat_9_5_0.php");

// 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-----

$privKey = new CkPrivateKey();
$success = $privKey->LoadPemFile('qa_data/ecc/secp256r1-key-pkcs8.pem');
if ($success != true) {
    print $privKey->lastErrorText() . "\n";
    exit;
}

// Get the public key.
// pubKey is a CkPublicKey
$pubKey = $privKey->GetPublicKey();
if ($privKey->get_LastMethodSuccess() != true) {
    print $privKey->lastErrorText() . "\n";
    exit;
}

// Save the public key to a PEM file.
$success = $pubKey->SavePemFile(false,'qa_data/ecc/secp256r1-pubkey.pem');
if ($success != true) {
    print $pubKey->lastErrorText() . "\n";

    exit;
}

// 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.' . "\n";

?>