fix(backend): check target IP before sending HTTP request

packages/backend/src/core/DownloadService.ts

@@ -6,7 +6,6 @@
 import * as fs from 'node:fs';
 import * as stream from 'node:stream/promises';
 import { Inject, Injectable } from '@nestjs/common';
-import ipaddr from 'ipaddr.js';
 import chalk from 'chalk';
 import got, * as Got from 'got';
 import { parse } from 'content-disposition';
@@ -70,13 +69,6 @@ export class DownloadService {
 			},
 			enableUnixSockets: false,
 		}).on('response', (res: Got.Response) => {
-			if ((process.env.NODE_ENV === 'production' || process.env.NODE_ENV === 'test') && !this.config.proxy && res.ip) {
-				if (this.isPrivateIp(res.ip)) {
-					this.logger.warn(`Blocked address: ${res.ip}`);
-					req.destroy();
-				}
-			}
-
 			const contentLength = res.headers['content-length'];
 			if (contentLength != null) {
 				const size = Number(contentLength);
@@ -139,18 +131,4 @@ export class DownloadService {
 			cleanup();
 		}
 	}
-
-	@bindThis
-	private isPrivateIp(ip: string): boolean {
-		const parsedIp = ipaddr.parse(ip);
-
-		for (const net of this.config.allowedPrivateNetworks ?? []) {
-			const cidr = ipaddr.parseCIDR(net);
-			if (cidr[0].kind() === parsedIp.kind() && parsedIp.match(ipaddr.parseCIDR(net))) {
-				return false;
-			}
-		}
-
-		return parsedIp.range() !== 'unicast';
-	}
 }

packages/backend/src/core/HttpRequestService.ts

@@ -6,6 +6,7 @@
 import * as http from 'node:http';
 import * as https from 'node:https';
 import * as net from 'node:net';
+import ipaddr from 'ipaddr.js';
 import CacheableLookup from 'cacheable-lookup';
 import fetch from 'node-fetch';
 import { HttpProxyAgent, HttpsProxyAgent } from 'hpagent';
@@ -25,6 +26,91 @@ export type HttpRequestSendOptions = {
 	validators?: ((res: Response) => void)[];
 };
 
+@Injectable()
+class HttpRequestServiceAgent extends http.Agent {
+	constructor(
+		@Inject(DI.config)
+		private config: Config,
+
+		options?: Object
+	) {
+		super(options);
+	}
+
+	@bindThis
+	public createConnection(options: Object, callback?: Function): net.Socket {
+		const socket = super.createConnection(options, callback)
+		.on('connect', ()=>{
+			const address = socket.remoteAddress;
+			if (process.env.NODE_ENV === 'production' || process.env.NODE_ENV === 'test') {
+				if (address && ipaddr.isValid(address)) {
+					if (this.isPrivateIp(address)) {
+						socket.destroy(new Error(`Blocked address: ${address}`));
+					}
+				}
+			}
+		});
+		return socket;
+	};
+
+	@bindThis
+	private isPrivateIp(ip: string): boolean {
+		const parsedIp = ipaddr.parse(ip);
+	
+		for (const net of this.config.allowedPrivateNetworks ?? []) {
+			const cidr = ipaddr.parseCIDR(net);
+			if (cidr[0].kind() === parsedIp.kind() && parsedIp.match(ipaddr.parseCIDR(net))) {
+				return false;
+			}
+		}
+	
+		return parsedIp.range() !== 'unicast';
+	}
+}
+
+@Injectable()
+class HttpsRequestServiceAgent extends https.Agent {
+	constructor(
+		@Inject(DI.config)
+		private config: Config,
+
+		options?: Object
+	) {
+		super(options);
+	}
+
+	@bindThis
+	public createConnection(options: Object, callback?: Function): net.Socket {
+		const socket = super.createConnection(options, callback)
+		.on('connect', ()=>{
+			const address = socket.remoteAddress;
+			if (process.env.NODE_ENV === 'production' || process.env.NODE_ENV === 'test') {
+				if (address && ipaddr.isValid(address)) {
+					if (this.isPrivateIp(address)) {
+						socket.destroy(new Error(`Blocked address: ${address}`));
+					}
+				}
+			}
+		});
+		return socket;
+	};
+
+	@bindThis
+	private isPrivateIp(ip: string): boolean {
+		const parsedIp = ipaddr.parse(ip);
+	
+		for (const net of this.config.allowedPrivateNetworks ?? []) {
+			const cidr = ipaddr.parseCIDR(net);
+			if (cidr[0].kind() === parsedIp.kind() && parsedIp.match(ipaddr.parseCIDR(net))) {
+				return false;
+			}
+		}
+	
+		return parsedIp.range() !== 'unicast';
+	}
+}
+
+
 @Injectable()
 export class HttpRequestService {
 	/**
@@ -57,14 +143,14 @@ export class HttpRequestService {
 			lookup: false,	// nativeのdns.lookupにfallbackしない
 		});
 
-		this.http = new http.Agent({
+		this.http = new HttpRequestServiceAgent(config, {
 			keepAlive: true,
 			keepAliveMsecs: 30 * 1000,
 			lookup: cache.lookup as unknown as net.LookupFunction,
 			localAddress: config.outgoingAddress,
 		});
 
-		this.https = new https.Agent({
+		this.https = new HttpsRequestServiceAgent(config, {
 			keepAlive: true,
 			keepAliveMsecs: 30 * 1000,
 			lookup: cache.lookup as unknown as net.LookupFunction,