From 65c9ca62de57fc86dc66de120dcf252269542ffb Mon Sep 17 00:00:00 2001
From: Sander Declerck <sander@sdsoftware.be>
Date: Fri, 31 Oct 2025 09:39:16 +0100
Subject: [PATCH] Subscribe to more error events to prevent the process from
 crashing

---
 .../src/registryProxy/mitmRequestHandler.js   | 23 +++++++++++++++++-
 .../src/registryProxy/plainHttpProxy.js       |  9 +++++--
 .../src/registryProxy/tunnelRequestHandler.js | 24 ++++++++++++-------
 3 files changed, 44 insertions(+), 12 deletions(-)

diff --git a/packages/safe-chain/src/registryProxy/mitmRequestHandler.js b/packages/safe-chain/src/registryProxy/mitmRequestHandler.js
index 63a8168..e95bb62 100644
--- a/packages/safe-chain/src/registryProxy/mitmRequestHandler.js
+++ b/packages/safe-chain/src/registryProxy/mitmRequestHandler.js
@@ -37,13 +37,19 @@ function createHttpsServer(hostname, isAllowed) {
     forwardRequest(req, hostname, res);
   }
 
-  return https.createServer(
+  const server = https.createServer(
     {
       key: cert.privateKey,
       cert: cert.certificate,
     },
     handleRequest
   );
+
+  server.on("error", (err) => {
+    ui.writeError(`Safe-chain: HTTPS server error: ${err.message}`);
+  });
+
+  return server;
 }
 
 function getRequestPathAndQuery(url) {
@@ -62,6 +68,11 @@ function forwardRequest(req, hostname, res) {
     res.end("Bad Gateway");
   });
 
+  req.on("error", (err) => {
+    ui.writeError(`Safe-chain: Error reading client request: ${err.message}`);
+    proxyReq.destroy();
+  });
+
   req.on("data", (chunk) => {
     proxyReq.write(chunk);
   });
@@ -88,6 +99,16 @@ function createProxyRequest(hostname, req, res) {
   }
 
   const proxyReq = https.request(options, (proxyRes) => {
+    proxyRes.on("error", (err) => {
+      ui.writeError(
+        `Safe-chain: Error reading upstream response: ${err.message}`
+      );
+      if (!res.headersSent) {
+        res.writeHead(502);
+        res.end("Bad Gateway");
+      }
+    });
+
     res.writeHead(proxyRes.statusCode, proxyRes.headers);
     proxyRes.pipe(res);
   });
diff --git a/packages/safe-chain/src/registryProxy/plainHttpProxy.js b/packages/safe-chain/src/registryProxy/plainHttpProxy.js
index e337b44..ac3dc69 100644
--- a/packages/safe-chain/src/registryProxy/plainHttpProxy.js
+++ b/packages/safe-chain/src/registryProxy/plainHttpProxy.js
@@ -43,8 +43,13 @@ export function handleHttpProxyRequest(req, res) {
       }
     )
     .on("error", (err) => {
-      res.writeHead(502);
-      res.end(`Bad Gateway: ${err.message}`);
+      if (!res.headersSent) {
+        res.writeHead(502);
+        res.end(`Bad Gateway: ${err.message}`);
+      } else {
+        // Headers already sent, just destroy the response
+        res.destroy();
+      }
     });
 
   req.on("error", () => {
diff --git a/packages/safe-chain/src/registryProxy/tunnelRequestHandler.js b/packages/safe-chain/src/registryProxy/tunnelRequestHandler.js
index c28a022..91b1c40 100644
--- a/packages/safe-chain/src/registryProxy/tunnelRequestHandler.js
+++ b/packages/safe-chain/src/registryProxy/tunnelRequestHandler.js
@@ -24,12 +24,6 @@ export function tunnelRequest(req, clientSocket, head) {
 function tunnelRequestToDestination(req, clientSocket, head) {
   const { port, hostname } = new URL(`http://${req.url}`);
 
-  clientSocket.on("error", () => {
-    // NO-OP
-    // This can happen if the client TCP socket sends RST instead of FIN.
-    // Not subscribing to 'close' event will cause node to throw and crash.
-  });
-
   const serverSocket = net.connect(port || 443, hostname, () => {
     clientSocket.write("HTTP/1.1 200 Connection Established\r\n\r\n");
     serverSocket.write(head);
@@ -37,6 +31,14 @@ function tunnelRequestToDestination(req, clientSocket, head) {
     clientSocket.pipe(serverSocket);
   });
 
+  clientSocket.on("error", () => {
+    // This can happen if the client TCP socket sends RST instead of FIN.
+    // Not subscribing to 'close' event will cause node to throw and crash.
+    if (serverSocket.writable) {
+      serverSocket.end();
+    }
+  });
+
   serverSocket.on("error", (err) => {
     ui.writeError(
       `Safe-chain: error connecting to ${hostname}:${port} - ${err.message}`
@@ -100,9 +102,13 @@ function tunnelRequestViaProxy(req, clientSocket, head, proxyUrl) {
           proxy.port || 8080
         } - ${err.message}`
       );
-      if (clientSocket.writable) {
-        clientSocket.end("HTTP/1.1 502 Bad Gateway\r\n\r\n");
-      }
+    } else {
+      ui.writeError(
+        `Safe-chain: proxy socket error after connection - ${err.message}`
+      );
+    }
+    if (clientSocket.writable) {
+      clientSocket.end("HTTP/1.1 502 Bad Gateway\r\n\r\n");
     }
   });