From 0572ca3c61dc76a59c8f97b43876881d43f51520 Mon Sep 17 00:00:00 2001
From: meows <b5c6@protonmail.com>
Date: Wed, 18 Dec 2019 08:44:41 -0600
Subject: [PATCH] rpc: enforce rpc api module availability

Fixes #20467

Signed-off-by: meows <b5c6@protonmail.com>
---
 rpc/endpoints.go | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/rpc/endpoints.go b/rpc/endpoints.go
index 8ca6d4eb0c..845acf849b 100644
--- a/rpc/endpoints.go
+++ b/rpc/endpoints.go
@@ -18,6 +18,7 @@ package rpc
 
 import (
 	"net"
+	"strings"
 
 	"github.com/ethereum/go-ethereum/log"
 )
@@ -27,6 +28,29 @@ func StartHTTPEndpoint(endpoint string, apis []API, modules []string, cors []str
 	// Generate the whitelist based on the allowed modules
 	whitelist := make(map[string]bool)
 	for _, module := range modules {
+		apiExists := false
+		for _, api := range apis {
+			if module == api.Namespace {
+				apiExists = true
+				break
+			}
+		}
+		if !apiExists {
+			log.Crit("invalid api module", "module", module, "available", func() string {
+				available := []string{}
+				outer:
+				for _, api := range apis {
+					// Only include unique api names
+					for _, av := range available {
+						if av == api.Namespace {
+							continue outer
+						}
+					}
+					available = append(available, api.Namespace)
+				}
+				return strings.Join(available, ",")
+			}())
+		}
 		whitelist[module] = true
 	}
 	// Register all the APIs exposed by the services