From 612a00b484435cb80225348c8ddae1278e24d661 Mon Sep 17 00:00:00 2001
From: ansuz <ansuz@transitiontech.ca>
Date: Fri, 10 Mar 2017 18:03:15 +0100
Subject: [PATCH] implement serverside RPC infrastructure

---
 NetfluxWebsocketSrv.js | 20 ++++++++++++++++++--
 config.js.dist         |  7 +++++++
 rpc.js                 | 37 +++++++++++++++++++++++++++++++++++++
 server.js              | 37 ++++++++++++++++++++++++++++---------
 4 files changed, 90 insertions(+), 11 deletions(-)
 create mode 100644 rpc.js

diff --git a/NetfluxWebsocketSrv.js b/NetfluxWebsocketSrv.js
index b15cdd33b..bd6b6da87 100644
--- a/NetfluxWebsocketSrv.js
+++ b/NetfluxWebsocketSrv.js
@@ -209,6 +209,21 @@ const handleMessage = function (ctx, user, msg) {
                     let parsedMsg = {state: 1, channel: parsed[1]};
                     sendMsg(ctx, user, [0, HISTORY_KEEPER_ID, 'MSG', user.id, JSON.stringify(parsedMsg)]);
                 });
+            } else if (ctx.rpc) {
+                /* RPC Calls...  */
+                var rpc_call = parsed.slice(1);
+
+                // slice off the sequence number and pass in the rest of the message
+                ctx.rpc(rpc_call, function (err, output) {
+                    if (err) {
+                        console.error('[' + err + ']', output);
+                        sendMsg(ctx, user, [seq, 'ACK']);
+                        sendMsg(ctx, user, [0, HISTORY_KEEPER_ID, 'MSG', user.id, JSON.stringify([parsed[0], 'ERROR', err])]);
+                        return
+                    }
+                    sendMsg(ctx, user, [seq, 'ACK']);
+                    sendMsg(ctx, user, [0, HISTORY_KEEPER_ID, 'MSG', user.id, JSON.stringify([parsed[0]].concat(output))]);
+                });
             }
             return;
         }
@@ -251,7 +266,7 @@ const handleMessage = function (ctx, user, msg) {
     }
 };
 
-let run = module.exports.run = function (storage, socketServer, config) {
+let run = module.exports.run = function (storage, socketServer, config, rpc) {
     /*  Channel removal timeout defaults to 60000ms (one minute) */
     config.channelRemovalTimeout =
         typeof(config.channelRemovalTimeout) === 'number'?
@@ -263,7 +278,8 @@ let run = module.exports.run = function (storage, socketServer, config) {
         channels: {},
         timeouts: {},
         store: storage,
-        config: config
+        config: config,
+        rpc: rpc,
     };
     setInterval(function () {
         Object.keys(ctx.users).forEach(function (userId) {
diff --git a/config.js.dist b/config.js.dist
index da80bb374..3818ae002 100644
--- a/config.js.dist
+++ b/config.js.dist
@@ -130,6 +130,13 @@ module.exports = {
      */
     openFileLimit: 2048,
 
+    /*  Cryptpad's socket server can be extended to respond to RPC calls
+     *  you can configure it to respond to custom RPC calls if you like.
+     *  provide the path to your RPC module here, or `false` if you would
+     *  like to disable the RPC interface completely
+     */
+    rpc: './rpc.js',
+
     /* it is recommended that you serve cryptpad over https
      * the filepaths below are used to configure your certificates
      */
diff --git a/rpc.js b/rpc.js
new file mode 100644
index 000000000..66973039b
--- /dev/null
+++ b/rpc.js
@@ -0,0 +1,37 @@
+/*  Use Nacl for checking signatures of messages
+
+*/
+var Nacl = require("tweetnacl");
+
+var RPC = module.exports;
+
+var pin = function (ctx, cb) { };
+var unpin = function (ctx, cb) { };
+var getHash = function (ctx, cb) { };
+var getTotalSize = function (ctx, cb) { };
+var getFileSize = function (ctx, cb) { };
+
+RPC.create = function (config, cb) {
+    // load pin-store...
+
+    console.log('loading rpc module...');
+    rpc = function (msg, respond) {
+        switch (msg[0]) {
+            case 'ECHO':
+                respond(void 0, msg);
+                break;
+            case 'PIN':
+            case 'UNPIN':
+            case 'GET_HASH':
+            case 'GET_TOTAL_SIZE':
+            case 'GET_FILE_SIZE':
+
+            default:
+                respond('UNSUPPORTED_RPC_CALL', msg);
+                break;
+        }
+    };
+
+    cb(void 0, rpc);
+};
+
diff --git a/server.js b/server.js
index 34f8cfedf..ea26778f9 100644
--- a/server.js
+++ b/server.js
@@ -117,13 +117,32 @@ httpServer.listen(config.httpPort,config.httpAddress,function(){
 
 var wsConfig = { server: httpServer };
 
-if(!config.useExternalWebsocket) {
-    if (websocketPort !== config.httpPort) {
-        console.log("setting up a new websocket server");
-        wsConfig = { port: websocketPort};
+var createSocketServer = function (err, rpc) {
+    if(!config.useExternalWebsocket) {
+        if (websocketPort !== config.httpPort) {
+            console.log("setting up a new websocket server");
+            wsConfig = { port: websocketPort};
+        }
+        var wsSrv = new WebSocketServer(wsConfig);
+        Storage.create(config, function (store) {
+            NetfluxSrv.run(store, wsSrv, config, rpc);
+        });
     }
-    var wsSrv = new WebSocketServer(wsConfig);
-    Storage.create(config, function (store) {
-        NetfluxSrv.run(store, wsSrv, config);
-    });
-}
+};
+
+var loadRPC = function (cb) {
+    config.rpc = typeof(config.rpc) === 'undefined'? './rpc.js' : config.rpc;
+
+    if (typeof(config.rpc) === 'string') {
+        // load pin store...
+        var Rpc = require(config.rpc);
+        Rpc.create(config, function (e, rpc) {
+            if (e) { throw e; }
+            cb(void 0, rpc);
+        });
+    } else {
+        cb();
+    }
+};
+
+loadRPC(createSocketServer);