Both slots on Yubikey are now polled for challenge/response

src/gui/DatabaseOpenWidget.cpp

@@ -70,9 +70,6 @@ DatabaseOpenWidget::DatabaseOpenWidget(QWidget* parent)
 
     connect(m_ui->buttonRedetectYubikey, SIGNAL(clicked()), SLOT(pollYubikey()));
     connect(m_ui->comboChallengeResponse, SIGNAL(activated(int)), SLOT(activateChallengeResponse()));
-
-    connect(YubiKey::instance(), SIGNAL(detected(int,bool)), SLOT(yubikeyDetected(int,bool)), Qt::QueuedConnection);
-    connect(YubiKey::instance(), SIGNAL(notFound()), SLOT(noYubikeyFound()), Qt::QueuedConnection);
 #else
     m_ui->checkChallengeResponse->setVisible(false);
     m_ui->buttonRedetectYubikey->setVisible(false);
@@ -98,10 +95,24 @@ void DatabaseOpenWidget::showEvent(QShowEvent* event)
     m_ui->editPassword->setFocus();
 
 #ifdef WITH_XC_YUBIKEY
+    connect(YubiKey::instance(), SIGNAL(detected(int,bool)), SLOT(yubikeyDetected(int,bool)), Qt::QueuedConnection);
+    connect(YubiKey::instance(), SIGNAL(detectComplete()), SLOT(yubikeyDetectComplete()), Qt::QueuedConnection);
+    connect(YubiKey::instance(), SIGNAL(notFound()), SLOT(noYubikeyFound()), Qt::QueuedConnection);
+
     pollYubikey();
 #endif
 }
 
+void DatabaseOpenWidget::hideEvent(QHideEvent* event)
+{
+    DialogyWidget::hideEvent(event);
+
+#ifdef WITH_XC_YUBIKEY
+    // Don't listen to any Yubikey events if we are hidden
+    disconnect(YubiKey::instance(), 0, this, 0);
+#endif
+}
+
 void DatabaseOpenWidget::load(const QString& filename)
 {
     m_filename = filename;
@@ -283,10 +294,6 @@ void DatabaseOpenWidget::yubikeyDetected(int slot, bool blocking)
     YkChallengeResponseKey yk(slot, blocking);
     // add detected YubiKey to combo box and encode blocking mode in LSB, slot number in second LSB
     m_ui->comboChallengeResponse->addItem(yk.getName(), QVariant((slot << 1) | blocking));
-    m_ui->comboChallengeResponse->setEnabled(true);
-    m_ui->checkChallengeResponse->setEnabled(true);
-    m_ui->buttonRedetectYubikey->setEnabled(true);
-    m_ui->yubikeyProgress->setVisible(false);
 
     if (config()->get("RememberLastKeyFiles").toBool()) {
         QHash<QString, QVariant> lastChallengeResponse = config()->get("LastChallengeResponse").toHash();
@@ -296,6 +303,14 @@ void DatabaseOpenWidget::yubikeyDetected(int slot, bool blocking)
     }
 }
 
+void DatabaseOpenWidget::yubikeyDetectComplete()
+{
+    m_ui->comboChallengeResponse->setEnabled(true);
+    m_ui->checkChallengeResponse->setEnabled(true);
+    m_ui->buttonRedetectYubikey->setEnabled(true);
+    m_ui->yubikeyProgress->setVisible(false);
+}
+
 void DatabaseOpenWidget::noYubikeyFound()
 {
     m_ui->buttonRedetectYubikey->setEnabled(true);

src/gui/DatabaseOpenWidget.h

@@ -51,6 +51,7 @@ signals:
 
 protected:
     void showEvent(QShowEvent* event) override;
+    void hideEvent(QHideEvent* event) override;
     CompositeKey databaseKey();
 
 protected slots:
@@ -63,6 +64,7 @@ private slots:
     void activateChallengeResponse();
     void browseKeyFile();
     void yubikeyDetected(int slot, bool blocking);
+    void yubikeyDetectComplete();
     void noYubikeyFound();
 
 protected:

src/keys/drivers/YubiKey.cpp

@@ -25,6 +25,7 @@
 #include <ykdef.h>
 #include <ykstatus.h>
 
+#include "core/Tools.h"
 #include "core/Global.h"
 #include "crypto/Random.h"
 
@@ -112,23 +113,36 @@ bool YubiKey::deinit()
 
 void YubiKey::detect()
 {
-    if (init()) {
-        for (int i = 1; i < 3; i++) {
-            YubiKey::ChallengeResult result;
-            QByteArray rand = randomGen()->randomArray(1);
-            QByteArray resp;
+    bool found = false;
 
+    if (init()) {
+        YubiKey::ChallengeResult result;
+        QByteArray rand = randomGen()->randomArray(1);
+        QByteArray resp;
+
+        // Check slot 1 and 2 for Challenge-Response HMAC capability
+        for (int i = 1; i <= 2; ++i) {
             result = challenge(i, false, rand, resp);
-            if (result == YubiKey::ALREADY_RUNNING) {
-                emit alreadyRunning();
-                return;
-            } else if (result != YubiKey::ERROR) {
-                emit detected(i, result == YubiKey::WOULDBLOCK);
-                return;
+            if (result == ALREADY_RUNNING) {
+                // Try this slot again after waiting
+                Tools::sleep(300);
+                result = challenge(i, false, rand, resp);
             }
+
+            if (result != ALREADY_RUNNING && result != ERROR) {
+                emit detected(i, result == WOULDBLOCK);
+                found = true;
+            }
+            // Wait between slots to let the yubikey settle
+            Tools::sleep(150);
         }
     }
-    emit notFound();
+
+    if (!found) {
+        emit notFound();
+    } else {
+        emit detectComplete();
+    }
 }
 
 bool YubiKey::getSerial(unsigned int& serial)
@@ -160,6 +174,7 @@ YubiKey::ChallengeResult YubiKey::challenge(int slot, bool mayBlock, const QByte
     }
 
     // yk_challenge_response() insists on 64 byte response buffer */
+    response.clear();
     response.resize(64);
 
     /* The challenge sent to the yubikey should always be 64 bytes for

src/keys/drivers/YubiKey.h

@@ -87,6 +87,11 @@ signals:
      */
     void detected(int slot, bool blocking);
 
+    /**
+     * Emitted when detection is complete
+     */
+    void detectComplete();
+
     /**
      * Emitted when the YubiKey was challenged and has returned a response.
      */