PHP extension wrapping ed25519, an Elliptic Curve Digital Signature Algortithm, developed by Dan Bernstein, Niels Duif, Tanja Lange, Peter Schwabe, and Bo-Yin Yang.
This extensions is based on two projects: ed25519 implemention from https://github.com/floodyberry/ed25519-donna and original PHP curve25519 extension from https://github.com/lt/php-curve25519-ext
git clone git:https://github.com/encedo/php-ed25519-ext.git
cd php-ed25519-ext
phpize
./configure
make
sudo make install
Finally add extension=ed25519.so to your /etc/php.ini
You can build it as a Debian package using
git clone git:https://github.com/encedo/php-ed25519-ext.git
cd php-ed25519-ext
sudo apt-get install php5-dev dh-php5
fakeroot debian/rules binary
Generate 32 secret random bytes from a cryptographically safe source e.g.
// PHP 7
$mySecret = random_bytes(32);
// <= PHP 5.6
$mySecret = openssl_random_pseudo_bytes(32);
Then generate the corresponding 32-byte public key by calling
$myPublic = ed25519_publickey($mySecret);
To sign a $message simply call
$signature = ed25519_sign($message, $mySecret, $myPublic);
To verify the $signature for a given $message against $myPublic call
$status = ed25519_sign_open($message, $myPublic, $signature);
If $status === TRUE the $signature is just fine :)
<?php
$mySecret = openssl_random_pseudo_bytes(32);
$myPublic = ed25519_publickey($mySecret);
$message = 'Hello, World!';
$signature = ed25519_sign($message, $mySecret, $myPublic);
var_dump( ed25519_sign_open($message, $myPublic, $signature) );
?>