Websocket client hanshake error 426 on upgrade - websocket

Question

Reader's digest version:
First time writing a websocket client. Java 1.8 using Eclipse. While on my workplace internal network getting a handshake error exception and the websocket log information tells me:
< Session 1c61123c-aa5f-4e59-a49d-b5d3c77c0bbd [598 ms]: Received handshake response:
< 426
< connection: Keep-Alive
< content-length: 29
< content-type: text/plain; charset=utf-8
< date: Mon, 12 Jun 2017 16:40:04 GMT
< server: nginx
Exception in thread "main" java.lang.RuntimeException: javax.websocket.DeploymentException: Handshake error.
at webSocketExample.WebsocketClientEndpoint.<init>(WebsocketClientEndpoint.java:60)
Details:
When I am connected to my internal work network and try to make a websocket connection I initially get connected but then I am sending a TCP reset. If I throw the code on my laptop and connect over a different network like my home Comcast connection the connection is made and I receive the initial data response from the server. I then take my laptop and hook it up to my internal work network and I go back to getting the handshake error.
I have been unable to resolve it yet with my internal security team as we don't do websocket development here so the knowledge base is a little lacking.
I set my proxy prior to calling this routine from my main. It has been verified that I am getting connected to the server but then I am sending a reset. Here is the code I am executing:
try {
System.setProperty("javax.net.debug", "all");
ClientManager client = ClientManager.createClient();
final SSLContextConfigurator defaultConfig = new SSLContextConfigurator();
defaultConfig.retrieve(System.getProperties());
SSLEngineConfigurator sslEngine = new SSLEngineConfigurator(defaultConfig, true, false, false);
client.getProperties().put(ClientProperties.SSL_ENGINE_CONFIGURATOR, sslEngine);
client.getProperties().put(ClientProperties.LOG_HTTP_UPGRADE, true);
client.connectToServer(new Endpoint() {
#Override
public void onOpen(Session session, EndpointConfig config) {
session.addMessageHandler(new MessageHandler.Whole<String>() {
#Override
public void onMessage(String message) {
System.out.println(message);
}
});
}
}, ClientEndpointConfig.Builder.create().build(),
new URI("wss://api.sandbox.gemini.com/v1/marketdata/BTCUSD"));
} catch (Exception e) {
throw new RuntimeException(e);
}
I have read all the posts/questions/answers that I have been able to find but haven't come up with anything yet. I am somewhat limited on what I can personally do on our network as we have pretty tight security but I can work with my security team to find answers if I get asked a question.
I would think it has to be internal to my work network and the proxy maybe but I haven't been able to resolve it. Also, this is the last part of the log information from the connection and error reporting:
Padded plaintext after DECRYPTION: len = 170
0000: 48 54 54 50 2F 31 2E 31 20 34 32 36 20 55 70 67 HTTP/1.1 426 Upg
0010: 72 61 64 65 20 52 65 71 75 69 72 65 64 0D 0A 44 rade Required..D
0020: 61 74 65 3A 20 4D 6F 6E 2C 20 31 32 20 4A 75 6E ate: Mon, 12 Jun
0030: 20 32 30 31 37 20 31 36 3A 35 30 3A 32 35 20 47 2017 16:50:25 G
0040: 4D 54 0D 0A 53 65 72 76 65 72 3A 20 6E 67 69 6E MT..Server: ngin
0050: 78 0D 0A 43 6F 6E 6E 65 63 74 69 6F 6E 3A 20 4B x..Connection: K
0060: 65 65 70 2D 41 6C 69 76 65 0D 0A 43 6F 6E 74 65 eep-Alive..Conte
0070: 6E 74 2D 54 79 70 65 3A 20 74 65 78 74 2F 70 6C nt-Type: text/pl
0080: 61 69 6E 3B 20 63 68 61 72 73 65 74 3D 75 74 66 ain; charset=utf
0090: 2D 38 0D 0A 43 6F 6E 74 65 6E 74 2D 4C 65 6E 67 -8..Content-Leng
00A0: 74 68 3A 20 32 39 0D 0A 0D 0A th: 29....
[Raw read (bb)]: length = 58
0000: 17 03 03 00 35 EC 0F C3 40 0D 18 B4 7B 53 C6 2D ....5...#....S.-
0010: F5 83 29 72 15 51 AC 31 8F 86 52 C9 3C 98 BB F8 ..)r.Q.1..R.<...
0020: 94 4A D7 3A 6E 17 8C 75 9E 58 25 0B AE B5 2F 13 .J.:n..u.X%.../.
0030: 8C 44 29 94 2F 4A 46 18 C9 1A .D)./JF...
Padded plaintext after DECRYPTION: len = 29
0000: 55 70 67 72 61 64 65 20 74 6F 20 57 65 62 53 6F Upgrade to WebSo
0010: 63 6B 65 74 20 72 65 71 75 69 72 65 64 cket required
> Session 6f920826-4b05-47bd-8cad-212038ff9fad [86 ms]: Sending handshake request:
> GET wss://api.sandbox.gemini.com/v1/marketdata/BTCUSD
> Connection: Upgrade
> Host: api.sandbox.gemini.com
> Origin: api.sandbox.gemini.com
> Sec-WebSocket-Key: nkgv7uk/bPSKBiOz5T/Bdg==
> Sec-WebSocket-Version: 13
> Upgrade: websocket
< Session 6f920826-4b05-47bd-8cad-212038ff9fad [600 ms]: Received handshake response:
< 426
< connection: Keep-Alive
< content-length: 29
< content-type: text/plain; charset=utf-8
< date: Mon, 12 Jun 2017 16:50:25 GMT
< server: nginx
If you got this far, thanks...
Adding sniffer information from my network team:
You establish a connection Pkt 263, which you are going through the proxy server, mcweb-a 170.137.249.117. Then you transmit data. The reset is sent in Pkt 280.
enter image description here

Answer 1

In case anyone comes across this. The issue was a problem with my proxy server. We had to add the specific endpoint as being allowable so it would skip some of the security checks.