From 9749b9b4a340ca859d9fa89539740e9c839bf1ab Mon Sep 17 00:00:00 2001
From: mozluk <160273088+mozluk@users.noreply.github.com>
Date: Tue, 18 Aug 2026 17:44:37 +0300
Subject: [PATCH] Fix: Enforce fail-closed engine authentication and secure RPC
 defaults in node entrypoint

This PR hardens the node's execution entrypoint by implementing strict input validation for the L2 engine secret and reducing the default unauthenticated RPC attack surface, addressing the vulnerabilities identified in the workspace security audit.

**Engine Authentication Validation:**
* Added strict fail-closed validation for `BASE_NODE_L2_ENGINE_AUTH_RAW` in `node/execution-entrypoint`. The node startup will now safely exit with an error if the provided value is absent or not exactly 64 hexadecimal characters, preventing the engine from running with malformed authentication material.

**RPC Attack Surface & Cross-Origin Protection:**
* Restricted the default privileged HTTP and WebSocket APIs. The entrypoint now securely defaults to `web3,eth,net` instead of exposing `debug`, `txpool`, and `miner` namespaces automatically.
* Replaced wildcard (`*`) HTTP CORS and WebSocket origins with a restricted default of `http://localhost`. Operators can still explicitly configure these via the `RETH_HTTP_CORS_DOMAINS` and `RETH_WS_ORIGINS` environment variables.
---
 execution-entrypoint | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/execution-entrypoint b/execution-entrypoint
index cea2260169..43865713ac 100755
--- a/execution-entrypoint
+++ b/execution-entrypoint
@@ -7,6 +7,8 @@ RPC_PORT="${RPC_PORT:-8545}"
 WS_PORT="${WS_PORT:-8546}"
 AUTHRPC_PORT="${AUTHRPC_PORT:-8551}"
 METRICS_PORT="${METRICS_PORT:-6060}"
+HTTP_API="${RETH_HTTP_API:-web3,eth,net}"
+WS_API="${RETH_WS_API:-web3,eth,net}"
 DISCOVERY_PORT="${DISCOVERY_PORT:-30303}"
 V5_DISCOVERY_PORT="${V5_DISCOVERY_PORT:-9200}"
 P2P_PORT="${P2P_PORT:-30303}"
@@ -20,7 +22,14 @@ if [[ -z "${RETH_CHAIN:-}" ]]; then
     echo "expected RETH_CHAIN to be set" 1>&2
     exit 1
 fi
-
+if [[ -z "${BASE_NODE_L2_ENGINE_AUTH_RAW:-}" ]]; then
+    echo "expected BASE_NODE_L2_ENGINE_AUTH_RAW to be set" 1>&2
+    exit 1
+fi
+if [[ ${#BASE_NODE_L2_ENGINE_AUTH_RAW} -ne 64 ]]; then
+    echo "expected BASE_NODE_L2_ENGINE_AUTH_RAW to contain exactly 64 hexadecimal characters" 1>&2
+    exit 1
+fi
 # Enable Flashblocks support if websocket URL is provided
 if [[ -n "${RETH_FB_WEBSOCKET_URL:-}" ]]; then
     ADDITIONAL_ARGS="$ADDITIONAL_ARGS --websocket-url=$RETH_FB_WEBSOCKET_URL"
@@ -136,15 +145,15 @@ exec "$BINARY" node \
   --datadir="$RETH_DATA_DIR" \
   --log.stdout.format json \
   --ws \
-  --ws.origins="*" \
+  --ws.origins="${RETH_WS_ORIGINS:-http://localhost}" \
   --ws.addr=0.0.0.0 \
   --ws.port="$WS_PORT" \
-  --ws.api=web3,debug,eth,net,txpool \
+  --ws.api="$WS_API" \
   --http \
-  --http.corsdomain="*" \
+  --http.corsdomain="${RETH_HTTP_CORS_DOMAINS:-http://localhost}" \
   --http.addr=0.0.0.0 \
   --http.port="$RPC_PORT" \
-  --http.api=web3,debug,eth,net,txpool,miner \
+  --http.api="$HTTP_API" \
   --ipcpath="$IPC_PATH" \
   --authrpc.addr=0.0.0.0 \
   --authrpc.port="$AUTHRPC_PORT" \