updater: fetch signed hashes from getmonero.org, verify downloads

components/UpdateDialog.qml

@@ -37,11 +37,12 @@ import "../components" as MoneroComponents
 Popup {
     id: updateDialog
 
+    property bool active: false
     property bool allowed: true
     property string error: ""
     property string filename: ""
+    property string hash: ""
     property double progress: url && downloader.total > 0 ? downloader.loaded * 100 / downloader.total : 0
-    property bool active: false
     property string url: ""
     property bool valid: false
     property string version: ""
@@ -55,8 +56,9 @@ Popup {
     padding: 20
     visible: active && allowed
 
-    function show(version, url) {
+    function show(version, url, hash) {
         updateDialog.error = "";
+        updateDialog.hash = hash;
         updateDialog.url = url;
         updateDialog.valid = false;
         updateDialog.version = version;
@@ -86,7 +88,7 @@ Popup {
 
         Text {
             id: statusText
-            color: MoneroComponents.Style.defaultFontColor
+            color: updateDialog.valid ? MoneroComponents.Style.green : MoneroComponents.Style.defaultFontColor
             font.family: MoneroComponents.Style.fontRegular.name
             font.pixelSize: 18
             visible: !errorText.visible
@@ -102,9 +104,9 @@ Popup {
                         + translationManager.emptyString;
                 }
                 if (updateDialog.valid) {
-                    return qsTr("Download finished") + translationManager.emptyString;
+                    return qsTr("Update downloaded, signature verified") + translationManager.emptyString;
                 }
-                return qsTr("Do you want to download new version?") + translationManager.emptyString;
+                return qsTr("Do you want to download and verify new version?") + translationManager.emptyString;
             }
         }
 
@@ -156,8 +158,9 @@ Popup {
                 onClicked: {
                     updateDialog.error = "";
                     updateDialog.filename = updateDialog.url.replace(/^.*\//, '');
-                    const downloadingStarted = downloader.get(updateDialog.url, function(error) {
+                    const downloadingStarted = downloader.get(updateDialog.url, updateDialog.hash, function(error) {
                         if (error) {
+                            console.error("Download failed", error);
                             updateDialog.error = qsTr("Download failed") + translationManager.emptyString;
                         } else {
                             updateDialog.valid = true;

main.qml

@@ -1978,15 +1978,11 @@ ApplicationWindow {
         closeWallet(Qt.quit);
     }
 
-    function onWalletCheckUpdatesComplete(update) {
-        if (update === "")
-            return
-        print("Update found: " + update)
-        var parts = update.split("|")
-        if (parts.length == 4) {
-            updateDialog.show(parts[0], isMac || isWindows || isLinux ? parts[3] : "");
-        } else {
-            print("Failed to parse update spec")
+    function onWalletCheckUpdatesComplete(version, downloadUrl, hash, firstSigner, secondSigner) {
+        const alreadyAsked = updateDialog.url == downloadUrl && updateDialog.hash == hash;
+        if (!alreadyAsked)
+        {
+            updateDialog.show(version, isMac || isWindows || isLinux ? downloadUrl : "", hash);
         }
     }
 

src/libwalletqt/WalletManager.cpp

@@ -41,6 +41,8 @@
 #include <QMutexLocker>
 #include <QString>
 
+#include "qt/updater.h"
+
 class WalletPassphraseListenerImpl : public  Monero::WalletListener
 {
 public:
@@ -464,12 +466,32 @@ bool WalletManager::saveQrCode(const QString &code, const QString &path) const
 void WalletManager::checkUpdatesAsync(const QString &software, const QString &subdir)
 {
     m_scheduler.run([this, software, subdir] {
-        emit checkUpdatesComplete(checkUpdates(software, subdir));
+        const auto updateInfo = Monero::WalletManager::checkUpdates(software.toStdString(), subdir.toStdString());
+        if (!std::get<0>(updateInfo))
+        {
+            return;
+        }
+
+        const QString version = QString::fromStdString(std::get<1>(updateInfo));
+        const QByteArray hashFromDns = QByteArray::fromHex(QString::fromStdString(std::get<2>(updateInfo)).toUtf8());
+        const QString downloadUrl = QString::fromStdString(std::get<4>(updateInfo));
+
+        try
+        {
+            const QString binaryFilename = QUrl(downloadUrl).fileName();
+            QPair<QString, QString> signers;
+            const QString signedHash = Updater().fetchSignedHash(binaryFilename, hashFromDns, signers).toHex();
+
+            qInfo() << "Update found" << version << downloadUrl << "hash" << signedHash << "signed by" << signers;
+            emit checkUpdatesComplete(version, downloadUrl, signedHash, signers.first, signers.second);
+        }
+        catch (const std::exception &e)
+        {
+            qCritical() << "Failed to fetch and verify signed hash:" << e.what();
+        }
     });
 }
 
-
-
 QString WalletManager::checkUpdates(const QString &software, const QString &subdir) const
 {
   qDebug() << "Checking for updates";

src/libwalletqt/WalletManager.h

@@ -36,7 +36,6 @@
 #include <QMutex>
 #include <QPointer>
 #include <QWaitCondition>
-#include <QMutex>
 #include "qt/FutureScheduler.h"
 #include "NetworkType.h"
 
@@ -192,7 +191,12 @@ signals:
     void walletPassphraseNeeded();
     void deviceButtonRequest(quint64 buttonCode);
     void deviceButtonPressed();
-    void checkUpdatesComplete(const QString &result) const;
+    void checkUpdatesComplete(
+        const QString &version,
+        const QString &downloadUrl,
+        const QString &hash,
+        const QString &firstSigner,
+        const QString &secondSigner) const;
     void miningStatus(bool isMining) const;
 
 public slots:

src/qt/downloader.cpp

@@ -31,6 +31,8 @@
 #include <QReadLocker>
 #include <QWriteLocker>
 
+#include "updater.h"
+
 namespace
 {
 
@@ -112,10 +114,10 @@ void Downloader::cancel()
     m_contents.clear();
 }
 
-bool Downloader::get(const QString &url, const QJSValue &callback)
+bool Downloader::get(const QString &url, const QString &hash, const QJSValue &callback)
 {
     auto future = m_scheduler.run(
-        [this, url]() {
+        [this, url, hash]() {
             DownloaderStateGuard stateGuard(m_active, m_mutex, [this]() {
                 emit activeChanged();
             });
@@ -153,6 +155,19 @@ bool Downloader::get(const QString &url, const QJSValue &callback)
                 return QJSValueList({"empty response"});
             }
 
+            try
+            {
+                const QByteArray calculatedHash = Updater().getHash(&response[0], response.size());
+                if (QByteArray::fromHex(hash.toUtf8()) != calculatedHash)
+                {
+                    return QJSValueList({"hash sum mismatch"});
+                }
+            }
+            catch (const std::exception &e)
+            {
+                return QJSValueList({e.what()});
+            }
+
             {
                 QWriteLocker locker(&m_mutex);
 

src/qt/downloader.h

@@ -44,7 +44,7 @@ public:
     ~Downloader();
 
     Q_INVOKABLE void cancel();
-    Q_INVOKABLE bool get(const QString &url, const QJSValue &callback);
+    Q_INVOKABLE bool get(const QString &url, const QString &hash, const QJSValue &callback);
     Q_INVOKABLE bool saveToFile(const QString &path) const;
 
 signals:

src/qt/network.cpp

@@ -117,6 +117,17 @@ void Network::getJSON(const QString &url, const QJSValue &callback) const
     get(url, callback, "application/json; charset=utf-8");
 }
 
+std::string Network::get(const QString &url, const QString &contentType /* = {} */) const
+{
+    std::string response;
+    QString error = get(std::shared_ptr<http_simple_client>(new http_simple_client()), url, response, contentType);
+    if (!error.isEmpty())
+    {
+        throw std::runtime_error(QString("failed to fetch %1: %2").arg(url).arg(error).toStdString());
+    }
+    return response;
+}
+
 QString Network::get(
     std::shared_ptr<http_simple_client> httpClient,
     const QString &url,

src/qt/network.h

@@ -77,6 +77,7 @@ public:
     Q_INVOKABLE void get(const QString &url, const QJSValue &callback, const QString &contentType = {}) const;
     Q_INVOKABLE void getJSON(const QString &url, const QJSValue &callback) const;
 
+    std::string get(const QString &url, const QString &contentType = {}) const;
     QString get(
         std::shared_ptr<epee::net_utils::http::http_simple_client> httpClient,
         const QString &url,

src/qt/updater.cpp

@@ -30,6 +30,7 @@
 
 #include <openpgp/hash.h>
 
+#include "network.h"
 #include "utils.h"
 
 Updater::Updater()
@@ -39,17 +40,41 @@ Updater::Updater()
     m_maintainers.emplace_back(fileGetContents(":/monero/utils/gpg_keys/luigi1111.asc").toStdString());
 }
 
-QPair<QString, QString> Updater::verifySignaturesAndHashSum(
+QByteArray Updater::fetchSignedHash(
+    const QString &binaryFilename,
+    const QByteArray &hashFromDns,
+    QPair<QString, QString> &signers) const
+{
+    static constexpr const char hashesTxtUrl[] = "https://web.getmonero.org/downloads/hashes.txt";
+    static constexpr const char hashesTxtSigUrl[] = "https://web.getmonero.org/downloads/hashes.txt.sig";
+
+    const Network network;
+    std::string hashesTxt = network.get(hashesTxtUrl);
+    std::string hashesTxtSig = network.get(hashesTxtSigUrl);
+
+    const QByteArray signedHash = verifyParseSignedHahes(
+        QByteArray(&hashesTxt[0], hashesTxt.size()),
+        QByteArray(&hashesTxtSig[0], hashesTxtSig.size()),
+        binaryFilename,
+        signers);
+
+    if (signedHash != hashFromDns)
+    {
+        throw std::runtime_error("DNS hash mismatch");
+    }
+
+    return signedHash;
+}
+
+QByteArray Updater::verifyParseSignedHahes(
     const QByteArray &armoredSignedHashes,
     const QByteArray &secondDetachedSignature,
     const QString &binaryFilename,
-    const void *binaryData,
-    size_t binarySize) const
+    QPair<QString, QString> &signers) const
 {
-    QString firstSigner;
-    const QString signedMessage = verifySignature(armoredSignedHashes, firstSigner);
+    const QString signedMessage = verifySignature(armoredSignedHashes, signers.first);
 
-    QString secondSigner = verifySignature(
+    signers.second = verifySignature(
         epee::span<const uint8_t>(
             reinterpret_cast<const uint8_t *>(armoredSignedHashes.data()),
             armoredSignedHashes.size()),
@@ -57,19 +82,31 @@ QPair<QString, QString> Updater::verifySignaturesAndHashSum(
             reinterpret_cast<const uint8_t *>(secondDetachedSignature.data()),
             secondDetachedSignature.size())));
 
-    if (firstSigner == secondSigner)
+    if (signers.first == signers.second)
     {
         throw std::runtime_error("both signatures were generated by the same person");
     }
 
-    const QByteArray signedHash = parseShasumOutput(signedMessage, binaryFilename);
+    return parseShasumOutput(signedMessage, binaryFilename);
+}
+
+QPair<QString, QString> Updater::verifySignaturesAndHashSum(
+    const QByteArray &armoredSignedHashes,
+    const QByteArray &secondDetachedSignature,
+    const QString &binaryFilename,
+    const void *binaryData,
+    size_t binarySize) const
+{
+    QPair<QString, QString> signers;
+    const QByteArray signedHash =
+        verifyParseSignedHahes(armoredSignedHashes, secondDetachedSignature, binaryFilename, signers);
     const QByteArray calculatedHash = getHash(binaryData, binarySize);
     if (signedHash != calculatedHash)
     {
         throw std::runtime_error("hash sum mismatch");
     }
 
-    return {firstSigner, secondSigner};
+    return signers;
 }
 
 QByteArray Updater::getHash(const void *data, size_t size) const

src/qt/updater.h

@@ -37,6 +37,11 @@ class Updater
 public:
     Updater();
 
+    QByteArray fetchSignedHash(
+        const QString &binaryFilename,
+        const QByteArray &hashFromDns,
+        QPair<QString, QString> &signers) const;
+    QByteArray getHash(const void *data, size_t size) const;
     QPair<QString, QString> verifySignaturesAndHashSum(
         const QByteArray &armoredSignedHashes,
         const QByteArray &secondDetachedSignature,
@@ -45,7 +50,11 @@ public:
         size_t binarySize) const;
 
 private:
-    QByteArray getHash(const void *data, size_t size) const;
+    QByteArray verifyParseSignedHahes(
+        const QByteArray &armoredSignedHashes,
+        const QByteArray &secondDetachedSignature,
+        const QString &binaryFilename,
+        QPair<QString, QString> &signers) const;
     QString verifySignature(const QByteArray &armoredSignedMessage, QString &signer) const;
     QString verifySignature(const epee::span<const uint8_t> data, const openpgp::signature_rsa &signature) const;
     QByteArray parseShasumOutput(const QString &message, const QString &filename) const;