From 7ee877821069fdedcbb225e533988187fe614526 Mon Sep 17 00:00:00 2001
From: ansuz <ansuz@transitiontech.ca>
Date: Fri, 21 Feb 2020 13:05:07 -0500
Subject: [PATCH] kick unauthorized users from restricted channels

and update dependencies
---
 lib/commands/metadata.js | 70 ++++++++++++++++++++++++++++++----------
 package-lock.json        |  4 +--
 package.json             |  2 +-
 3 files changed, 55 insertions(+), 21 deletions(-)

diff --git a/lib/commands/metadata.js b/lib/commands/metadata.js
index 21132dd23..a5bca0dca 100644
--- a/lib/commands/metadata.js
+++ b/lib/commands/metadata.js
@@ -71,7 +71,7 @@ Data.setMetadata = function (Env, safeKey, data, cb, Server) {
     if (Meta.commands.indexOf(command) === -1) { return void cb('UNSUPPORTED_COMMAND'); }
 
     queueMetadata(channel, function (next) {
-        Data.getMetadata(Env, channel, function (err, metadata) {
+        Data.getMetadataRaw(Env, channel, function (err, metadata) {
             if (err) {
                 cb(err);
                 return void next();
@@ -133,34 +133,70 @@ Data.setMetadata = function (Env, safeKey, data, cb, Server) {
                     return void next();
                 }
 
-
-            // chainpad-server@4.0.3 supports a removeFromChannel method
-            // Server.removeFromChannel(channelName, userId);
-            // this lets us kick users from restricted channels
-
-            // XXX RESTRICT
-            // if the metadata changes and includes an allowed list
-            // kick any current users from the channel
-            // if they aren't on it.
-
-            // review Server.channelBroadcast as used for EEXPIRED
-            // send them to the user in question, from historyKeeper
-
+                // send the message back to the person who changed it
+                // since we know they're allowed to see it
                 cb(void 0, metadata);
                 next();
 
                 const metadata_cache = Env.metadata_cache;
                 const channel_cache = Env.channel_cache;
 
+                // update the cached metadata
                 metadata_cache[channel] = metadata;
 
+                // as well as the metadata that's attached to the index...
+                // XXX determine if we actually need this...
                 var index = Util.find(channel_cache, [channel, 'index']);
                 if (index && typeof(index) === 'object') { index.metadata = metadata; }
 
-                Server.channelBroadcast(channel, JSON.stringify(metadata), Env.historyKeeper.id);
+                // it's easy to check if the channel is restricted
+                const isRestricted = metadata.restricted;
+                // and these values will be used in any case
+                const s_metadata = JSON.stringify(metadata);
+                const hk_id = Env.historyKeeper.id;
+
+                if (!isRestricted) {
+                    // pre-allow-list behaviour
+                    // if it's not restricted, broadcast the new metadata to everyone
+                    return void Server.channelBroadcast(channel, s_metadata, hk_id);
+                }
+
+                // otherwise derive the list of users (unsafeKeys) that are allowed to stay
+                const allowed = HK.listAllowedUsers(metadata);
+                // anyone who is not allowed will get the same error message
+                const s_error = JSON.stringify({
+                    error: 'ERESTRICTED',
+                    channel: channel,
+                });
+
+                // iterate over the channel's userlist
+                const toRemove = [];
+                Server.getChannelUserList(channel).forEach(function (userId) {
+                    const session = HK.getNetfluxSession(Env, userId);
+
+                    // if the user is allowed to remain, send them the metadata
+                    if (HK.isUserSessionAllowed(allowed, session)) {
+                        return void Server.send(userId, [
+                            0,
+                            hk_id,
+                            'MSG',
+                            userId,
+                            s_metadata
+                        ], function () {});
+                    }
+                    // otherwise they are not in the list.
+                    // send them an error and kick them out!
+                    Server.send(userId, [
+                        0,
+                        hk_id,
+                        'MSG',
+                        userId,
+                        s_error
+                    ], function () {});
+                });
+
+                Server.removeFromChannel(channel, toRemove);
             });
         });
     });
 };
-
-
diff --git a/package-lock.json b/package-lock.json
index d4a119d75..c3e9c6905 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -113,9 +113,7 @@
       }
     },
     "chainpad-server": {
-      "version": "4.0.2",
-      "resolved": "https://registry.npmjs.org/chainpad-server/-/chainpad-server-4.0.2.tgz",
-      "integrity": "sha512-9NrFsATd70uAdksxsCZBIJ/SiREmJ6QLYTNaeFLH/nJpeZ2b7wblVGABCj3JYWvngdEZ7Umc+afbWH8sUmtgeQ==",
+      "version": "4.0.3",
       "requires": {
         "nthen": "0.1.8",
         "pull-stream": "^3.6.9",
diff --git a/package.json b/package.json
index 81be1c7f8..43a28fdb2 100644
--- a/package.json
+++ b/package.json
@@ -13,7 +13,7 @@
   },
   "dependencies": {
     "chainpad-crypto": "^0.2.2",
-    "chainpad-server": "^4.0.0",
+    "chainpad-server": "^4.0.3",
     "express": "~4.16.0",
     "fs-extra": "^7.0.0",
     "get-folder-size": "^2.0.1",