deps,http: http_parser set max header size to 8KB

CVE-2018-12121

PR-URL: nodejs-private/node-private#143
Ref: nodejs-private/security#139
Ref: nodejs-private/http-parser-private#2
Reviewed-By: Anatoli Papirovski <apapirovski@mac.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rod Vagg <rod@vagg.org>
Reviewed-By: Anna Henningsen <anna@addaleax.net>

Author: mcollina

deps/http_parser/http_parser.gyp

@@ -56,7 +56,7 @@
         'defines': [ 'HTTP_PARSER_STRICT=0' ],
         'include_dirs': [ '.' ],
       },
-      'defines': [ 'HTTP_PARSER_STRICT=0' ],
+      'defines': [ 'HTTP_MAX_HEADER_SIZE=8192', 'HTTP_PARSER_STRICT=0' ],
       'sources': [ './http_parser.c', ],
       'conditions': [
         ['OS=="win"', {
@@ -79,7 +79,7 @@
         'defines': [ 'HTTP_PARSER_STRICT=1' ],
         'include_dirs': [ '.' ],
       },
-      'defines': [ 'HTTP_PARSER_STRICT=1' ],
+      'defines': [ 'HTTP_MAX_HEADER_SIZE=8192', 'HTTP_PARSER_STRICT=1' ],
       'sources': [ './http_parser.c', ],
       'conditions': [
         ['OS=="win"', {

src/node_http_parser.cc

@@ -610,6 +610,8 @@ class Parser : public AsyncWrap {
     size_t nparsed =
       http_parser_execute(&parser_, &settings, data, len);
 
+    enum http_errno err = HTTP_PARSER_ERRNO(&parser_);
+
     Save();
 
     // Unassign the 'buffer_' variable
@@ -624,9 +626,7 @@ class Parser : public AsyncWrap {
     Local<Integer> nparsed_obj = Integer::New(env()->isolate(), nparsed);
     // If there was a parse error in one of the callbacks
     // TODO(bnoordhuis) What if there is an error on EOF?
-    if (!parser_.upgrade && nparsed != len) {
-      enum http_errno err = HTTP_PARSER_ERRNO(&parser_);
-
+    if ((!parser_.upgrade && nparsed != len) || err != HPE_OK) {
       Local<Value> e = Exception::Error(env()->parse_error_string());
       Local<Object> obj = e->ToObject(env()->isolate());
       obj->Set(env()->bytes_parsed_string(), nparsed_obj);

test/parallel/test-http-max-headers-count.js

@@ -7,14 +7,14 @@ let requests = 0;
 let responses = 0;
 
 const headers = {};
-const N = 2000;
+const N = 100;
 for (let i = 0; i < N; ++i) {
   headers[`key${i}`] = i;
 }
 
 const maxAndExpected = [ // for server
   [50, 50],
-  [1500, 1500],
+  [1500, 102],
   [0, N + 2] // Host and Connection
 ];
 let max = maxAndExpected[requests][0];
@@ -35,7 +35,7 @@ server.maxHeadersCount = max;
 server.listen(0, function() {
   const maxAndExpected = [ // for client
     [20, 20],
-    [1200, 1200],
+    [1200, 103],
     [0, N + 3] // Connection, Date and Transfer-Encoding
   ];
   doRequest();

test/sequential/test-http-max-http-headers.js

@@ -0,0 +1,155 @@
+'use strict';
+
+const assert = require('assert');
+const common = require('../common');
+const http = require('http');
+const net = require('net');
+const MAX = 8 * 1024; // 8KB
+
+// Verify that we cannot receive more than 8KB of headers.
+
+function once(cb) {
+  let called = false;
+  return () => {
+    if (!called) {
+      called = true;
+      cb();
+    }
+  };
+}
+
+function finished(client, callback) {
+  'abort error end'.split(' ').forEach((e) => {
+    client.on(e, once(() => setImmediate(callback)));
+  });
+}
+
+function fillHeaders(headers, currentSize, valid = false) {
+  headers += 'a'.repeat(MAX - headers.length - 3);
+  // Generate valid headers
+  if (valid) {
+    // TODO(mcollina): understand why -9 is needed instead of -1
+    headers = headers.slice(0, -9);
+  }
+  return headers + '\r\n\r\n';
+}
+
+const timeout = common.platformTimeout(10);
+
+function writeHeaders(socket, headers) {
+  const array = [];
+
+  // this is off from 1024 so that \r\n does not get split
+  const chunkSize = 1000;
+  let last = 0;
+
+  for (let i = 0; i < headers.length / chunkSize; i++) {
+    const current = (i + 1) * chunkSize;
+    array.push(headers.slice(last, current));
+    last = current;
+  }
+
+  // safety check we are chunking correctly
+  assert.strictEqual(array.join(''), headers);
+
+  next();
+
+  function next() {
+    if (socket.write(array.shift())) {
+      if (array.length === 0) {
+        socket.end();
+      } else {
+        setTimeout(next, timeout);
+      }
+    } else {
+      socket.once('drain', next);
+    }
+  }
+}
+
+function test1() {
+  let headers =
+    'HTTP/1.1 200 OK\r\n' +
+    'Content-Length: 0\r\n' +
+    'X-CRASH: ';
+
+  // OK, Content-Length, 0, X-CRASH, aaa...
+  const currentSize = 2 + 14 + 1 + 7;
+  headers = fillHeaders(headers, currentSize);
+
+  const server = net.createServer((sock) => {
+    sock.once('data', (chunk) => {
+      writeHeaders(sock, headers);
+      sock.resume();
+    });
+  });
+
+  server.listen(0, common.mustCall(() => {
+    const port = server.address().port;
+    const client = http.get({ port: port }, common.mustNotCall(() => {}));
+
+    client.on('error', common.mustCall((err) => {
+      assert.strictEqual(err.code, 'HPE_HEADER_OVERFLOW');
+      server.close();
+      setImmediate(test2);
+    }));
+  }));
+}
+
+const test2 = common.mustCall(() => {
+  let headers =
+    'GET / HTTP/1.1\r\n' +
+    'Host: localhost\r\n' +
+    'Agent: node\r\n' +
+    'X-CRASH: ';
+
+  // /, Host, localhost, Agent, node, X-CRASH, a...
+  const currentSize = 1 + 4 + 9 + 5 + 4 + 7;
+  headers = fillHeaders(headers, currentSize);
+
+  const server = http.createServer(common.mustNotCall());
+
+  server.on('clientError', common.mustCall((err) => {
+    assert.strictEqual(err.code, 'HPE_HEADER_OVERFLOW');
+  }));
+
+  server.listen(0, common.mustCall(() => {
+    const client = net.connect(server.address().port);
+    client.on('connect', () => {
+      writeHeaders(client, headers);
+      client.resume();
+    });
+
+    finished(client, common.mustCall((err) => {
+      server.close();
+      setImmediate(test3);
+    }));
+  }));
+});
+
+const test3 = common.mustCall(() => {
+  let headers =
+    'GET / HTTP/1.1\r\n' +
+    'Host: localhost\r\n' +
+    'Agent: node\r\n' +
+    'X-CRASH: ';
+
+  // /, Host, localhost, Agent, node, X-CRASH, a...
+  const currentSize = 1 + 4 + 9 + 5 + 4 + 7;
+  headers = fillHeaders(headers, currentSize, true);
+
+  const server = http.createServer(common.mustCall((req, res) => {
+    res.end('hello world');
+    setImmediate(server.close.bind(server));
+  }));
+
+  server.listen(0, common.mustCall(() => {
+    const client = net.connect(server.address().port);
+    client.on('connect', () => {
+      writeHeaders(client, headers);
+      client.resume();
+    });
+  }));
+});
+
+test1();