Create AutoUpdater, teach it to check new updates

It can't read a diff or apply an update yet, just check.

qtox.pro

@@ -57,7 +57,7 @@ contains(JENKINS,YES) {
 # Rules for Windows, Mac OSX, and Linux
 win32 {
     RC_FILE = windows/qtox.rc
-    LIBS += -liphlpapi -L$$PWD/libs/lib -ltoxav -ltoxcore -ltoxencryptsave -ltoxdns -lvpx -lpthread
+    LIBS += -liphlpapi -L$$PWD/libs/lib -ltoxav -ltoxcore -ltoxencryptsave -ltoxdns -lvpx -lpthread -lsodium
     LIBS += -L$$PWD/libs/lib -lopencv_core248 -lopencv_highgui248 -lopencv_imgproc248 -lOpenAL32 -lopus
     LIBS += -lz -lopengl32 -lole32 -loleaut32 -luuid -lvfw32 -ljpeg -ltiff -lpng -ljasper -lIlmImf -lHalf -lws2_32
 } else {
@@ -76,7 +76,7 @@ win32 {
 	    LIBS += -Wl,-Bdynamic -lv4l1 -lv4l2 -lavformat -lavcodec -lavutil -lswscale -lusb-1.0
 
         } else {
-            LIBS += -L$$PWD/libs/lib/ -ltoxcore -ltoxav -ltoxencryptsave -ltoxdns -lvpx -lopenal -lopencv_core -lopencv_highgui -lopencv_imgproc
+            LIBS += -L$$PWD/libs/lib/ -ltoxcore -ltoxav -ltoxencryptsave -ltoxdns -lvpx -lsodium -lopenal -lopencv_core -lopencv_highgui -lopencv_imgproc
         }
 
         contains(JENKINS, YES) {
@@ -146,7 +146,8 @@ HEADERS  += src/widget/form/addfriendform.h \
     src/ipc.h \
     src/widget/toxuri.h \
     src/toxdns.h \
-    src/widget/toxsave.h
+    src/widget/toxsave.h \
+    src/autoupdate.h
 
 SOURCES += \
     src/widget/form/addfriendform.cpp \
@@ -209,4 +210,5 @@ SOURCES += \
     src/widget/toxuri.cpp \
     src/toxdns.cpp \
     src/ipc.cpp \
-    src/widget/toxsave.cpp    
+    src/widget/toxsave.cpp \    
+    src/autoupdate.cpp

src/autoupdate.cpp

@@ -0,0 +1,76 @@
+#include "src/autoupdate.h"
+#include <QNetworkAccessManager>
+#include <QNetworkReply>
+#include <QCoreApplication>
+
+#include <sodium.h>
+
+#ifdef _WIN32
+const QString AutoUpdater::platform = "win32";
+#else
+const QString AutoUpdater::platform = "win32"; ///TODO: FIXME: undefine, we want an empty qstring
+#endif
+const QString AutoUpdater::updateServer = "http://127.0.0.1";
+const QString AutoUpdater::checkURI = AutoUpdater::updateServer+"/qtox/"+AutoUpdater::platform+"/version";
+const QString AutoUpdater::flistURI = AutoUpdater::updateServer+"/qtox/"+AutoUpdater::platform+"/flist";
+const QString AutoUpdater::filesURI = AutoUpdater::updateServer+"/qtox/"+AutoUpdater::platform+"/files/";
+unsigned char AutoUpdater::key[crypto_sign_PUBLICKEYBYTES] =
+{
+    0xa5, 0x80, 0xf3, 0xb7, 0xd0, 0x10, 0xc0, 0xf9, 0xd6, 0xcf, 0x48, 0x15, 0x99, 0x70, 0x92, 0x49,
+    0xf6, 0xe8, 0xe5, 0xe2, 0x6c, 0x73, 0x8c, 0x48, 0x25, 0xed, 0x01, 0x72, 0xf7, 0x6c, 0x17, 0x28
+};
+
+bool AutoUpdater::isUpdateAvailable()
+{
+    QString newVersion = getUpdateVersion();
+    if (newVersion.isEmpty() || newVersion == GIT_VERSION)
+        return false;
+    else
+        return true;
+}
+
+QString AutoUpdater::getUpdateVersion()
+{
+    QString version;
+
+    // Updates only for supported platforms
+    if (platform.isEmpty())
+        return version;
+
+    QNetworkAccessManager *manager = new QNetworkAccessManager;
+
+    QNetworkReply* reply = manager->get(QNetworkRequest(QUrl(checkURI)));
+    while (!reply->isFinished())
+        qApp->processEvents();
+
+    if (reply->error() != QNetworkReply::NoError)
+    {
+        qWarning() << "AutoUpdater: getUpdateVersion: network error: "<<reply->errorString();
+        return version;
+    }
+
+    QByteArray data = reply->readAll();
+
+    // Check updater protocol version
+    if ((int)data[0] != '1')
+    {
+        qWarning() << "AutoUpdater: getUpdateVersion: Bad protocol version "<<(uint8_t)data[0];
+        return version;
+    }
+
+    // Check the signature
+    QByteArray sigData = data.mid(1, crypto_sign_BYTES);
+    unsigned char* sig = (unsigned char*)sigData.data();
+    QByteArray msgData = data.mid(1+crypto_sign_BYTES);
+    unsigned char* msg = (unsigned char*)msgData.data();
+
+    if (crypto_sign_verify_detached(sig, msg, msgData.size(), key) != 0)
+    {
+        qCritical() << "AutoUpdater: getUpdateVersion: RECEIVED FORGED VERSION FILE FROM "<<updateServer;
+        return version;
+    }
+
+    version = msgData;
+
+    return version;
+}

src/autoupdate.h

@@ -0,0 +1,47 @@
+/*
+    Copyright (C) 2014 by Project Tox <https://tox.im>
+
+    This file is part of qTox, a Qt-based graphical interface for Tox.
+
+    This program is libre software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+    See the COPYING file for more details.
+*/
+
+
+#ifndef AUTOUPDATE_H
+#define AUTOUPDATE_H
+
+#include <QString>
+
+/// Handles checking and applying updates for qTox
+class AutoUpdater
+{
+public:
+    /// Connects to the qTox update server, returns true if an update is available for download
+    /// Will call getUpdateVersion, and as such may block and processEvents
+    static bool isUpdateAvailable();
+    /// Fetch the version string of the last update available from the qTox update server
+    /// Will try to follow qTox's proxy settings, may block and processEvents
+    static QString getUpdateVersion();
+
+private:
+    AutoUpdater() = delete;
+
+private:
+    // Constants
+    static const QString updateServer; ///< Hostname of the qTox update server
+    static const QString platform; ///< Name of platform we're trying to get updates for
+    static const QString checkURI; ///< URI of the file containing the latest version string
+    static const QString flistURI; ///< URI of the file containing info on each file (hash, signature, size, name, ..)
+    static const QString filesURI; ///< URI of the actual files of the latest version
+    static unsigned char key[];
+};
+
+#endif // AUTOUPDATE_H

src/main.cpp

@@ -27,6 +27,8 @@
 #include <QDateTime>
 #include <QMutexLocker>
 
+#include <sodium.h>
+
 #ifdef LOG_TO_FILE
 static QtMessageHandler dflt;
 static QTextStream* logFile {nullptr};
@@ -55,6 +57,8 @@ int main(int argc, char *argv[])
     a.setApplicationName("qTox");
     a.setOrganizationName("Tox");
 
+    sodium_init(); // For the auto-updater
+
 #ifdef LOG_TO_FILE
     logFile = new QTextStream;
     dflt = qInstallMessageHandler(nullptr);