AesGcmCrypto Driver

July 11, 2026 · View on GitHub

Symmetric encryption via OpenSSL AES-256-GCM. Use this driver when libsodium is not available on the host.

Requirements

  • PHP 8.1+ (covered by CakePHP 5)
  • OpenSSL with aes-256-gcm support (OpenSSL 1.1.1+)

Verify support:

php -r "var_dump(in_array('aes-256-gcm', openssl_get_cipher_methods(true)));"
# bool(true)

Key generation

php -r "echo base64_encode(random_bytes(32)), PHP_EOL;"

Store the result in your environment — never hardcode it:

VERIFICATION_AESGCM_KEY="...base64-key..."

Configuration

// config/verification.php
'crypto' => [
    'driver' => 'aes-gcm',
    'key'    => base64_decode(env('VERIFICATION_AESGCM_KEY', '')),
],

See configuration.md for the full crypto reference.

vs SodiumCrypto

Both drivers are secure. Prefer SodiumCrypto when libsodium is available. See sodium_crypto.md.

Documentation

Full documentation index: ../index.md