Send User-Agent from the network request in http proxy CONNECT command

Some proxies can discriminate based on the User-Agent when sent a
CONNECT command for establishing a HTTPS connection.
With this change, if the User-Agent header is set in the QNetworkRequest
then it will be passed to the http socket engine for use in the connect
command sent to the proxy.
As before, "Mozilla/5.0" will be used by default when no user agent
has been set.

Task-number: QTBUG-17223
Reviewed-by: Markus Goetz

src/network/access/qhttpnetworkconnectionchannel.cpp

@@ -579,6 +579,12 @@ bool QHttpNetworkConnectionChannel::ensureConnection()
             connectHost = connection->d_func()->networkProxy.hostName();
             connectPort = connection->d_func()->networkProxy.port();
         }
+        if (socket->proxy().type() == QNetworkProxy::HttpProxy) {
+            // Make user-agent field available to HTTP proxy socket engine (QTBUG-17223)
+            QByteArray value = request.headerField("user-agent");
+            if (!value.isEmpty())
+                socket->setProperty("_q_user-agent", value);
+        }
 #endif
         if (ssl) {
 #ifndef QT_NO_OPENSSL

src/network/socket/qabstractsocket.cpp

@@ -556,6 +556,10 @@ bool QAbstractSocketPrivate::initSocketLayer(QAbstractSocket::NetworkLayerProtoc
         q->setErrorString(QAbstractSocket::tr("Operation on socket is not supported"));
         return false;
     }
+#ifndef QT_NO_NETWORKPROXY
+    //copy user agent to socket engine (if it has been set)
+    socketEngine->setProperty("_q_user-agent", q->property("_q_user-agent"));
+#endif
     if (!socketEngine->initialize(q->socketType(), protocol)) {
 #if defined (QABSTRACTSOCKET_DEBUG)
         qDebug("QAbstractSocketPrivate::initSocketLayer(%s, %s) failed (%s)",

src/network/socket/qhttpsocketengine.cpp

@@ -501,7 +501,13 @@ void QHttpSocketEngine::slotSocketConnected()
     data += path;
     data += " HTTP/1.1\r\n";
     data += "Proxy-Connection: keep-alive\r\n"
-            "User-Agent: Mozilla/5.0\r\n"
+            "User-Agent: ";
+    QVariant v = property("_q_user-agent");
+    if (v.isValid())
+        data += v.toByteArray();
+    else
+        data += "Mozilla/5.0";
+    data += "\r\n"
             "Host: " + peerAddress + "\r\n";
     QAuthenticatorPrivate *priv = QAuthenticatorPrivate::getPrivate(d->authenticator);
     //qDebug() << "slotSocketConnected: priv=" << priv << (priv ? (int)priv->method : -1);

src/network/ssl/qsslsocket.cpp

@@ -1736,6 +1736,8 @@ void QSslSocket::connectToHostImplementation(const QString &hostName, quint16 po
     }
 #ifndef QT_NO_NETWORKPROXY
     d->plainSocket->setProxy(proxy());
+    //copy user agent down to the plain socket (if it has been set)
+    d->plainSocket->setProperty("_q_user-agent", property("_q_user-agent"));
 #endif
     QIODevice::open(openMode);
     d->plainSocket->connectToHost(hostName, port, openMode);

tests/auto/qnetworkreply/tst_qnetworkreply.cpp

@@ -4970,7 +4970,9 @@ void tst_QNetworkReply::httpProxyCommands()
     QNetworkProxy proxy(QNetworkProxy::HttpProxy, "127.0.0.1", proxyServer.serverPort());
 
     manager.setProxy(proxy);
-    QNetworkReplyPtr reply = manager.get(QNetworkRequest(url));
+    QNetworkRequest request(url);
+    request.setRawHeader("User-Agent", "QNetworkReplyAutoTest/1.0");
+    QNetworkReplyPtr reply = manager.get(request);
     manager.setProxy(QNetworkProxy());
 
     // wait for the finished signal
@@ -4988,6 +4990,12 @@ void tst_QNetworkReply::httpProxyCommands()
 
     QString receivedHeader = proxyServer.receivedData.left(expectedCommand.length());
     QCOMPARE(receivedHeader, expectedCommand);
+
+    //QTBUG-17223 - make sure the user agent from the request is sent to proxy server even for CONNECT
+    int uapos = proxyServer.receivedData.indexOf("User-Agent");
+    int uaend = proxyServer.receivedData.indexOf("\r\n", uapos);
+    QByteArray uaheader = proxyServer.receivedData.mid(uapos, uaend - uapos);
+    QCOMPARE(uaheader, QByteArray("User-Agent: QNetworkReplyAutoTest/1.0"));
 }
 
 class ProxyChangeHelper : public QObject {