Curve25519

Curve25519 implements the missing functionality of sign/verify on elliptic curve 25519.

• Cryptographically compatible sign/verify
• Built in cache for last key calculations
• Sodium variant of the sign function (~2000x faster)

Usage

$curve25519 = new Curve25519();
$msg = 'Hello, world!';

$privateKey = random_bytes( 32 );
$sig = $curve25519->sign( $msg, $privateKey );

$publicKey = $curve25519->getPublicKeyFromPrivateKey( $privateKey );
$verify = $curve25519->verify( $sig, $msg, $publicKey );

if( !$verify )
    exit( 1 );

Requirements

• PHP >= 5.6

Recommended

• PHP >= 7.2
• Sodium

Installation

Require through Composer:

{
    "require": {
        "deemru/curve25519": "1.0.*"
    }
}

Notice

• sign_sodium hashes private key internally by SHA-512
• Beware of rseed functionality (for experts only)
• Consider to use ED25519_NO_SHA512SK sodium build