when sent to the server.
To implement a secure authentication channel:
- Create a key pair using the com.threerings.presents.tool.KeyPairGen tool. You will need to
distribute the public key with your client, and the private key with the server.
- On your server during initialization, use PresentsConnectionManager.setPrivateKey to set the
private key. It can take the key string gerenated by KeyPairGen. This will return true if the
key was sucessfully set and the server supports the encryption necessary.
- On your client before authenticating, use Client.setPublicKey to set the public key. As with
setPrivateKey, it will return true if the client supports the encryption necessary.
That's it! You should now be authenticating over a secure encrypted channel. The server can
still accept unsecured authentication attempts (for the purpose of telling the client it needs a
new version to get the server's public key). A failure to decrypt the client credientials on the
server will return a new "m.failed_to_secure" authentication code.
Handshake process:
- The client generates a random 128-bit key, and encodes it with the public key using a 32-bit
salt (PublicKeyCredentials). This is sent to the server as a SecureRequest.
- The server decrypts the i128-bit key using its private key and verifies it against the salt. If
verification fails, a failed secure response is returned and the client will authenticate over a
clear channel. If verification succeeds, the server generates a random 128-bit AES key and
encodes it with the 128-bit key sent from the client. This is sent back to the client as a
SecureResponse.
- The client will decode the AES key sent from the server (using the random key it generated at
the start of the handshake). Using the AES key, the client will encrypt their credentials using
an AESAuthRequest and send it to the server.
- The server can now decrypt the credentials from the client and pass the AESAuthRequest to the
configured authenticators to complete authentication. If the server fails to decrypt the
credentials a "m.failed_to_secure" authentication code is returned to the client.
git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@6477 542714f4-19e9-0310-aa3c-eee0fc999fb1
Mark Johnson
ae6c134546