Are there any best practices for validating Public Keys before importing them in PHP?

When importing public keys in PHP, it is important to validate them to ensure they are in the correct format and are not tampered with. One common method to validate public keys is by using the openssl_pkey_get_public() function, which will return a resource if the key is valid. Additionally, you can use regular expressions to check if the key is in the correct format before importing it.

```php
// Validate public key before importing
function validatePublicKey($publicKey) {
    $keyResource = openssl_pkey_get_public($publicKey);
    
    if ($keyResource === false) {
        return false;
    }
    
    return true;
}

// Example usage
$publicKey = "-----BEGIN PUBLIC KEY-----\nMIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAzN7QH3lP7zv2X1LXe5V9\n2o1HcE5lGm2B1rJLmR9oYl3D9a3gH6Fw7gV+9JrZ3b2P6a5i8YjK1Ew5+TyP3oJq\n7z3uGzj4lR9Bf4H5k4uq+2U2h9z4WvWMzRzFmXhZ7oV5Z3Fm7zqDyU2iL4R2X7O+\n0cV5FyLw7oZz5Wf2m3d3pZz1h9Bd8Y2x7XPR3CfMh3j7BtB5v3n1R2j4n5E2P8j\n6n4C1n5z2q7E3R1K5z7C8n3z2w7D4V7K2z6N3Z4B2f1Z3A2f4R2C6K7B2f5V3D4\nR5Z5C2n7D6Z4A3n4V2z4F5C3Z6K3Z5C7N2b4V7F6K3B6N3Z5