From 7f9b63a24c422a401ac9e2610c1e73344509d6f9 Mon Sep 17 00:00:00 2001
From: Evan <evanpelle@gmail.com>
Date: Tue, 5 May 2026 14:59:09 -0600
Subject: [PATCH] Increase max intent size to 2kb (#3852)
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## Description:

Raised MAX_INTENT_SIZE from 500 to 2000 bytes — the move_warship intent
could exceed the old limit and get rejected.
Removed the separate MAX_CONFIG_INTENT_SIZE (also 2000) and the
intentType branching, since both paths now share the same cap.
## Please complete the following:

- [ ] 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
---
 src/server/ClientMsgRateLimiter.ts        | 18 +++---------------
 src/server/GameServer.ts                  |  3 ---
 tests/server/ClientMsgRateLimiter.test.ts | 10 ++++++++++
 3 files changed, 13 insertions(+), 18 deletions(-)

diff --git a/src/server/ClientMsgRateLimiter.ts b/src/server/ClientMsgRateLimiter.ts
index d243b6460..99e88beb4 100644
--- a/src/server/ClientMsgRateLimiter.ts
+++ b/src/server/ClientMsgRateLimiter.ts
@@ -3,8 +3,7 @@ import { ClientID } from "../core/Schemas";
 
 const INTENTS_PER_SECOND = 10;
 const INTENTS_PER_MINUTE = 150;
-const MAX_INTENT_SIZE = 500;
-const MAX_CONFIG_INTENT_SIZE = 2000;
+const MAX_INTENT_SIZE = 2000;
 const TOTAL_BYTES = 2 * 1024 * 1024; // 2MB per client
 export type RateLimitResult = "ok" | "limit" | "kick";
 
@@ -17,30 +16,19 @@ interface ClientBucket {
 export class ClientMsgRateLimiter {
   private buckets = new Map<ClientID, ClientBucket>();
 
-  check(
-    clientID: ClientID,
-    type: string,
-    bytes: number,
-    intentType?: string,
-  ): RateLimitResult {
+  check(clientID: ClientID, type: string, bytes: number): RateLimitResult {
     const bucket = this.getOrCreate(clientID);
     bucket.totalBytes += bytes;
 
     if (bucket.totalBytes >= TOTAL_BYTES) return "kick";
 
     if (type === "intent") {
-      // Config updates are lobby-only and not stored in turn history,
-      // so they can be larger than regular intents.
-      const maxSize =
-        intentType === "update_game_config"
-          ? MAX_CONFIG_INTENT_SIZE
-          : MAX_INTENT_SIZE;
       // Intents are stored in turn history for the duration of the game, so
       // oversized intents would accumulate and fill up server RAM.
       // Intents are also sent to all players, so it increase outgoing
       // data.
       // Intents should never be larger than MAX_INTENT_SIZE, so we assume the client is malicious.
-      if (bytes > maxSize) {
+      if (bytes > MAX_INTENT_SIZE) {
         return "kick";
       }
       if (
diff --git a/src/server/GameServer.ts b/src/server/GameServer.ts
index 2f6175776..21f3a4418 100644
--- a/src/server/GameServer.ts
+++ b/src/server/GameServer.ts
@@ -349,13 +349,10 @@ export class GameServer {
         }
         const clientMsg = parsed.data;
         const bytes = Buffer.byteLength(message, "utf8");
-        const intentType =
-          clientMsg.type === "intent" ? clientMsg.intent.type : undefined;
         const rateResult = this.intentRateLimiter.check(
           client.clientID,
           clientMsg.type,
           bytes,
-          intentType,
         );
         if (rateResult === "kick") {
           this.log.warn(`Client rate limit exceeded, kicking`, {
diff --git a/tests/server/ClientMsgRateLimiter.test.ts b/tests/server/ClientMsgRateLimiter.test.ts
index 9732d3c40..31c5a6db8 100644
--- a/tests/server/ClientMsgRateLimiter.test.ts
+++ b/tests/server/ClientMsgRateLimiter.test.ts
@@ -28,6 +28,16 @@ describe("ClientMsgRateLimiter", () => {
       }
       expect(limiter.check(CLIENT_B, "intent", SMALL)).toBe("ok");
     });
+
+    it("allows intents up to MAX_INTENT_SIZE", () => {
+      const limiter = new ClientMsgRateLimiter();
+      expect(limiter.check(CLIENT_A, "intent", 2000)).toBe("ok");
+    });
+
+    it("kicks intents exceeding MAX_INTENT_SIZE", () => {
+      const limiter = new ClientMsgRateLimiter();
+      expect(limiter.check(CLIENT_A, "intent", 2001)).toBe("kick");
+    });
   });
 
   describe("non-intent messages", () => {