Password Lock
MIT Licensed - feel free to use to enhance the security of any of your PHP projects
Wraps Bcrypt-SHA384 in Authenticated Encryption. Published by Paragon Initiative Enteprises. Check out our other open source projects too.
Depends on defuse/php-encryption for authenticated symmetric-key encryption.
How is this different than "peppering"?
Peppering strategies are usually accomplished through a keyed hash function (e.g. HMAC-SHA256) and applies to the password before it's passed to the salted hash API (i.e. bcrypt). If your pepper/HMAC key is ever compromised, you have to reset every user's password and it becomes a headache.
A hash then encrypt strategy offers agility; if your secret key is compromised (but, miraculously, the hashes are not), you can decrypt all of your users' hashes then re-encrypt them with a new key and they'll never suffer the inconvenience of an unscheduled password reset.
How much more secure is this than just using bcrypt?
-
You don't have to worry about the 72 character limit for bcrypt
-
You don't have to worry about accidentally creating a null-byte truncation vulnerability
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If your database gets hacked, and your database is on a separate machine from your webserver, the attacker has to first decrypt the hashes before attempting to crack any of them.
Here's a proof-of-concept for the first two points.
But realistically, this library is only about as a secure as bcrypt.
Usage Examples
Hash Password, Encrypt Hash, Authenticate Ciphertext
use \ParagonIE\PasswordLock\PasswordLock;
use \Defuse\Crypto\Key;
$key = Key::createNewRandomKey();
if (isset($_POST['password'])) {
if (!is_string($_POST['password'])) {
die("Password must be a string");
}
$storeMe = PasswordLock::hashAndEncrypt($_POST['password'], $key);
}
Verify MAC, Decrypt Ciphertext, Verify Password
if (isset($_POST['password'])) {
if (!is_string($_POST['password'])) {
die("Password must be a string");
}
if (PasswordLock::decryptAndVerify($_POST['password'], $storeMe, $key)) {
// Success!
}
}
Re-encrypt a hash with a different encryption key
$newKey = \Defuse\Crypto\Key::createNewRandomKey();
$newHash = PasswordLock::rotateKey($storeMe, $key, $newKey);
Migrate from Version 1 of the library
$newHash = PasswordLock::upgradeFromVersion1(
$_POST['password'],
$oldHash,
$oldKey,
$newKey
);
Support Contracts
If your company uses this library in their products or services, you may be
interested in purchasing a support contract from Paragon Initiative Enterprises.