From 59cd930b6cec038d36d55d014bd96d33de44814b Mon Sep 17 00:00:00 2001
From: Zaid Abdulla <zaid@genieacs.com>
Date: Sun, 4 Aug 2019 12:40:02 -0700
Subject: [PATCH] Support more charsets using iconv-lite

---
 build/build.ts      |  1 +
 lib/cwmp.ts         | 44 +++++++++++++++++++++++++++++++++++++++-----
 npm-shrinkwrap.json | 36 +++++++++++++++++++++++++++++++++---
 package.json        |  1 +
 4 files changed, 74 insertions(+), 8 deletions(-)

diff --git a/build/build.ts b/build/build.ts
index 025aff1..e507495 100644
--- a/build/build.ts
+++ b/build/build.ts
@@ -64,6 +64,7 @@ const externals = [
   "child_process",
   "dgram",
   "url",
+  "iconv-lite",
   "koa",
   "koa-router",
   "koa-compress",
diff --git a/lib/cwmp.ts b/lib/cwmp.ts
index 75b024d..3daf1ab 100644
--- a/lib/cwmp.ts
+++ b/lib/cwmp.ts
@@ -50,6 +50,7 @@ import { IncomingMessage, ServerResponse } from "http";
 import { Readable } from "stream";
 import { promisify } from "util";
 import { TLSSocket } from "tls";
+import { decode, encodingExists } from "iconv-lite";
 import { dependencies as DEPENDENCIES } from "../package.json";
 import { parseXmlDeclaration } from "./xml-parser";
 import * as debug from "./debug";
@@ -1106,6 +1107,15 @@ export function listener(
     });
 }
 
+function decodeString(buffer: Buffer, charset: string): string {
+  try {
+    return buffer.toString(charset);
+  } catch (err) {
+    if (encodingExists(charset)) return decode(buffer, charset);
+  }
+  return null;
+}
+
 async function listenerAsync(
   httpRequest: IncomingMessage,
   httpResponse: ServerResponse
@@ -1233,10 +1243,36 @@ async function listenerAsync(
   if (!charset) {
     const parse = parseXmlDeclaration(body);
     const e = parse ? parse.find(s => s.localName === "encoding") : null;
-    charset = e ? e.value : "utf8";
+    charset = e ? e.value.toLowerCase() : "utf8";
   }
 
-  const bodyStr = body.toString(charset);
+  const bodyStr = decodeString(body, charset);
+
+  if (bodyStr == null) {
+    const msg = `Unknown encoding '${charset}'`;
+    logger.accessError({
+      message: "XML parse error",
+      parseError: msg,
+      sessionContext: sessionContext || {
+        httpRequest: httpRequest,
+        httpResponse: httpResponse
+      }
+    });
+    httpResponse.setHeader("Content-Length", Buffer.byteLength(msg));
+    httpResponse.writeHead(400, { Connection: "close" });
+    if (sessionContext) {
+      if (sessionContext.debug)
+        debug.outgoingHttpResponse(httpResponse, sessionContext.deviceId, msg);
+    } else {
+      const cacheSnapshot = await localCache.getCurrentSnapshot();
+      const d = !!localCache.getConfig(cacheSnapshot, "cwmp.debug", {
+        remoteAddress: httpResponse.connection.remoteAddress
+      });
+      if (d) debug.outgoingHttpResponse(httpResponse, null, msg);
+    }
+    httpResponse.end(msg);
+    return;
+  }
 
   async function parsedRpc(_sessionContext, rpc, parseWarnings): Promise<void> {
     for (const w of parseWarnings) {
@@ -1283,9 +1319,7 @@ async function listenerAsync(
       const d = !!localCache.getConfig(cacheSnapshot, "cwmp.debug", {
         remoteAddress: httpResponse.connection.remoteAddress
       });
-      if (d) {
-        debug.outgoingHttpResponse(httpResponse, null, error.message);
-      }
+      if (d) debug.outgoingHttpResponse(httpResponse, null, error.message);
     }
     httpResponse.end(error.message);
     return;
diff --git a/npm-shrinkwrap.json b/npm-shrinkwrap.json
index ff447b3..fc25732 100644
--- a/npm-shrinkwrap.json
+++ b/npm-shrinkwrap.json
@@ -3670,6 +3670,17 @@
         "chardet": "^0.7.0",
         "iconv-lite": "^0.4.24",
         "tmp": "^0.0.33"
+      },
+      "dependencies": {
+        "iconv-lite": {
+          "version": "0.4.24",
+          "resolved": "https://registry.npmjs.org/iconv-lite/-/iconv-lite-0.4.24.tgz",
+          "integrity": "sha512-v3MXnZAcvnywkTUEZomIActle7RXXeedOR31wwl7VlyoXO4Qi9arvSenNQWne1TcRwhCL1HwLI21bEqdpj8/rA==",
+          "dev": true,
+          "requires": {
+            "safer-buffer": ">= 2.1.2 < 3"
+          }
+        }
       }
     },
     "extglob": {
@@ -4355,9 +4366,9 @@
       "dev": true
     },
     "iconv-lite": {
-      "version": "0.4.24",
-      "resolved": "https://registry.npmjs.org/iconv-lite/-/iconv-lite-0.4.24.tgz",
-      "integrity": "sha512-v3MXnZAcvnywkTUEZomIActle7RXXeedOR31wwl7VlyoXO4Qi9arvSenNQWne1TcRwhCL1HwLI21bEqdpj8/rA==",
+      "version": "0.5.0",
+      "resolved": "https://registry.npmjs.org/iconv-lite/-/iconv-lite-0.5.0.tgz",
+      "integrity": "sha512-NnEhI9hIEKHOzJ4f697DMz9IQEXr/MMJ5w64vN2/4Ai+wRnvV7SBrL0KLoRlwaKVghOc7LQ5YkPLuX146b6Ydw==",
       "requires": {
         "safer-buffer": ">= 2.1.2 < 3"
       }
@@ -5937,6 +5948,15 @@
           "requires": {
             "ms": "^2.1.1"
           }
+        },
+        "iconv-lite": {
+          "version": "0.4.24",
+          "resolved": "https://registry.npmjs.org/iconv-lite/-/iconv-lite-0.4.24.tgz",
+          "integrity": "sha512-v3MXnZAcvnywkTUEZomIActle7RXXeedOR31wwl7VlyoXO4Qi9arvSenNQWne1TcRwhCL1HwLI21bEqdpj8/rA==",
+          "optional": true,
+          "requires": {
+            "safer-buffer": ">= 2.1.2 < 3"
+          }
         }
       }
     },
@@ -7664,6 +7684,16 @@
         "http-errors": "1.7.3",
         "iconv-lite": "0.4.24",
         "unpipe": "1.0.0"
+      },
+      "dependencies": {
+        "iconv-lite": {
+          "version": "0.4.24",
+          "resolved": "https://registry.npmjs.org/iconv-lite/-/iconv-lite-0.4.24.tgz",
+          "integrity": "sha512-v3MXnZAcvnywkTUEZomIActle7RXXeedOR31wwl7VlyoXO4Qi9arvSenNQWne1TcRwhCL1HwLI21bEqdpj8/rA==",
+          "requires": {
+            "safer-buffer": ">= 2.1.2 < 3"
+          }
+        }
       }
     },
     "rc": {
diff --git a/package.json b/package.json
index c1d787b..e0f9816 100644
--- a/package.json
+++ b/package.json
@@ -20,6 +20,7 @@
     "tools": "tools"
   },
   "dependencies": {
+    "iconv-lite": "^0.5.0",
     "jsonwebtoken": "^8.5.1",
     "koa": "^2.7.0",
     "koa-bodyparser": "^4.2.1",