Update socket rate limiting (#3447)

## Description:

On replays, there can be a burst of traffic from hashes, so instead just
have a 2MB limit per client for the entire game. Also the winner message
can be 100s of kb on a large game with many players, so now we don't
need to put a special case for that.

## Please complete the following:

- [x] I have added screenshots for all UI updates
- [x] I process any text displayed to the user through translateText()
and I've added it to the en.json file
- [x] I have added relevant tests to the test directory
- [x] I confirm I have thoroughly tested these changes and take full
responsibility for any bugs introduced

## Please put your Discord username so you can be contacted if a bug or
regression is found:

evan

tests/server/ClientMsgRateLimiter.test.ts

@@ -5,7 +5,6 @@ const CLIENT_A = "clientA" as any;
 const CLIENT_B = "clientB" as any;
 
 const SMALL = 100;
-const LARGE = 501; // over MAX_INTENT_BYTES
 
 describe("ClientMsgRateLimiter", () => {
   describe("intent messages", () => {
@@ -14,11 +13,6 @@ describe("ClientMsgRateLimiter", () => {
       expect(limiter.check(CLIENT_A, "intent", SMALL)).toBe("ok");
     });
 
-    it("kicks on oversized intent", () => {
-      const limiter = new ClientMsgRateLimiter();
-      expect(limiter.check(CLIENT_A, "intent", LARGE)).toBe("kick");
-    });
-
     it("limits when per-second count exceeded", () => {
       const limiter = new ClientMsgRateLimiter();
       for (let i = 0; i < 10; i++) {
@@ -36,34 +30,46 @@ describe("ClientMsgRateLimiter", () => {
     });
   });
 
-  describe("winner messages", () => {
-    it("allows first winner message", () => {
+  describe("non-intent messages", () => {
+    it("does not rate-limit non-intent messages", () => {
       const limiter = new ClientMsgRateLimiter();
-      expect(limiter.check(CLIENT_A, "winner", 50000)).toBe("ok");
+      for (let i = 0; i < 20; i++) {
+        expect(limiter.check(CLIENT_A, "winner", 50)).toBe("ok");
+      }
     });
 
-    it("allows up to 3 winner messages", () => {
+    it("does not rate-limit ping messages", () => {
       const limiter = new ClientMsgRateLimiter();
-      expect(limiter.check(CLIENT_A, "winner", 50000)).toBe("ok");
-      expect(limiter.check(CLIENT_A, "winner", 50000)).toBe("ok");
-      expect(limiter.check(CLIENT_A, "winner", 50000)).toBe("ok");
-      expect(limiter.check(CLIENT_A, "winner", 50000)).toBe("kick");
-    });
-
-    it("winner does not consume intent rate limit", () => {
-      const limiter = new ClientMsgRateLimiter();
-      limiter.check(CLIENT_A, "winner", 50000);
-      expect(limiter.check(CLIENT_A, "intent", SMALL)).toBe("ok");
+      for (let i = 0; i < 20; i++) {
+        expect(limiter.check(CLIENT_A, "ping", 50)).toBe("ok");
+      }
     });
   });
 
-  describe("other messages", () => {
-    it("applies rate limiting to other message types", () => {
+  describe("total bytes limit", () => {
+    it("kicks when cumulative bytes reach 2MB", () => {
       const limiter = new ClientMsgRateLimiter();
-      for (let i = 0; i < 10; i++) {
-        expect(limiter.check(CLIENT_A, "ping", 50)).toBe("ok");
+      const chunkSize = 512 * 1024; // 512KB
+      // Send 3 chunks = 1.5MB, should be ok
+      for (let i = 0; i < 3; i++) {
+        expect(limiter.check(CLIENT_A, "other", chunkSize)).toBe("ok");
       }
-      expect(limiter.check(CLIENT_A, "ping", 50)).toBe("limit");
+      // 4th chunk pushes to 2MB, should kick
+      expect(limiter.check(CLIENT_A, "other", chunkSize)).toBe("kick");
+    });
+
+    it("byte tracking is per client", () => {
+      const limiter = new ClientMsgRateLimiter();
+      const almostFull = 2 * 1024 * 1024 - 1;
+      expect(limiter.check(CLIENT_A, "other", almostFull)).toBe("ok");
+      // CLIENT_B should still be fine
+      expect(limiter.check(CLIENT_B, "other", 100)).toBe("ok");
+    });
+
+    it("kicks on bytes regardless of message type", () => {
+      const limiter = new ClientMsgRateLimiter();
+      const twoMB = 2 * 1024 * 1024;
+      expect(limiter.check(CLIENT_A, "intent", twoMB)).toBe("kick");
     });
   });
 });