Password Health Check

src/CMakeLists.txt

@@ -48,6 +48,7 @@ set(keepassx_SOURCES
         core/Merger.cpp
         core/Metadata.cpp
         core/PasswordGenerator.cpp
+        core/PasswordHealth.cpp
         core/PassphraseGenerator.cpp
         core/SignalMultiplexer.cpp
         core/ScreenLockListener.cpp
@@ -149,8 +150,12 @@ set(keepassx_SOURCES
         gui/dbsettings/DatabaseSettingsWidgetMetaDataSimple.cpp
         gui/dbsettings/DatabaseSettingsWidgetEncryption.cpp
         gui/dbsettings/DatabaseSettingsWidgetMasterKey.cpp
-        gui/dbsettings/DatabaseSettingsWidgetStatistics.cpp
-        gui/dbsettings/DatabaseSettingsPageStatistics.cpp
+        gui/reports/ReportsWidget.cpp
+        gui/reports/ReportsDialog.cpp
+        gui/reports/ReportsWidgetHealthcheck.cpp
+        gui/reports/ReportsPageHealthcheck.cpp
+        gui/reports/ReportsWidgetStatistics.cpp
+        gui/reports/ReportsPageStatistics.cpp
         gui/settings/SettingsWidget.cpp
         gui/widgets/ElidedLabel.cpp
         gui/widgets/PopupHelpWidget.cpp

src/browser/BrowserSettings.cpp

@@ -19,6 +19,7 @@
 
 #include "BrowserSettings.h"
 #include "core/Config.h"
+#include "core/PasswordHealth.h"
 
 BrowserSettings* BrowserSettings::m_instance(nullptr);
 
@@ -541,7 +542,7 @@ QJsonObject BrowserSettings::generatePassword()
         m_passwordGenerator.setCharClasses(passwordCharClasses());
         m_passwordGenerator.setFlags(passwordGeneratorFlags());
         const QString pw = m_passwordGenerator.generatePassword();
-        password["entropy"] = m_passwordGenerator.estimateEntropy(pw);
+        password["entropy"] = PasswordHealth(pw).entropy();
         password["password"] = pw;
     } else {
         m_passPhraseGenerator.setWordCount(passPhraseWordCount());

src/cli/Estimate.cpp

@@ -19,6 +19,7 @@
 #include "cli/Utils.h"
 
 #include "cli/TextStream.h"
+#include "core/PasswordHealth.h"
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -49,10 +50,9 @@ static void estimate(const char* pwd, bool advanced)
 {
     TextStream out(Utils::STDOUT, QIODevice::WriteOnly);
 
-    double e = 0.0;
     int len = static_cast<int>(strlen(pwd));
     if (!advanced) {
-        e = ZxcvbnMatch(pwd, nullptr, nullptr);
+        const auto e = PasswordHealth(pwd).entropy();
         // clang-format off
         out << QObject::tr("Length %1").arg(len, 0) << '\t'
             << QObject::tr("Entropy %1").arg(e, 0, 'f', 3) << '\t'
@@ -62,7 +62,7 @@ static void estimate(const char* pwd, bool advanced)
         int ChkLen = 0;
         ZxcMatch_t *info, *p;
         double m = 0.0;
-        e = ZxcvbnMatch(pwd, nullptr, &info);
+        const auto e = ZxcvbnMatch(pwd, nullptr, &info);
         for (p = info; p; p = p->Next) {
             m += p->Entrpy;
         }

src/core/PasswordGenerator.cpp

@@ -19,7 +19,6 @@
 #include "PasswordGenerator.h"
 
 #include "crypto/Random.h"
-#include <zxcvbn.h>
 
 const char* PasswordGenerator::DefaultExcludedChars = "";
 
@@ -31,11 +30,6 @@ PasswordGenerator::PasswordGenerator()
 {
 }
 
-double PasswordGenerator::estimateEntropy(const QString& password)
-{
-    return ZxcvbnMatch(password.toLatin1(), nullptr, nullptr);
-}
-
 void PasswordGenerator::setLength(int length)
 {
     if (length <= 0) {

src/core/PasswordGenerator.h

@@ -57,7 +57,6 @@ class PasswordGenerator
 public:
     PasswordGenerator();
 
-    double estimateEntropy(const QString& password);
     void setLength(int length);
     void setCharClasses(const CharClasses& classes);
     void setFlags(const GeneratorFlags& flags);

src/core/PasswordHealth.cpp

@@ -0,0 +1,184 @@
+/*
+ *  Copyright (C) 2019 KeePassXC Team <[email protected]>
+ *
+ *  This program is free 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 2 or (at your option)
+ *  version 3 of the License.
+ *
+ *  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
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <QApplication>
+#include <QString>
+
+#include "Database.h"
+#include "Entry.h"
+#include "Group.h"
+#include "PasswordHealth.h"
+#include "zxcvbn.h"
+
+PasswordHealth::PasswordHealth(double entropy)
+    : m_score(entropy)
+    , m_entropy(entropy)
+{
+    switch (quality()) {
+    case Quality::Bad:
+    case Quality::Poor:
+        m_scoreReasons << QApplication::tr("Very weak password");
+        m_scoreDetails << QApplication::tr("Password entropy is %1 bits").arg(QString::number(m_entropy, 'f', 2));
+        break;
+
+    case Quality::Weak:
+        m_scoreReasons << QApplication::tr("Weak password");
+        m_scoreDetails << QApplication::tr("Password entropy is %1 bits").arg(QString::number(m_entropy, 'f', 2));
+        break;
+
+    default:
+        // No reason or details for good and excellent passwords
+        break;
+    }
+}
+
+PasswordHealth::PasswordHealth(QString pwd)
+    : PasswordHealth(ZxcvbnMatch(pwd.toLatin1(), nullptr, nullptr))
+{
+}
+
+void PasswordHealth::setScore(int score)
+{
+    m_score = score;
+}
+
+void PasswordHealth::adjustScore(int amount)
+{
+    m_score += amount;
+}
+
+QString PasswordHealth::scoreReason() const
+{
+    return m_scoreReasons.join("\n");
+}
+
+void PasswordHealth::addScoreReason(QString reason)
+{
+    m_scoreReasons << reason;
+}
+
+QString PasswordHealth::scoreDetails() const
+{
+    return m_scoreDetails.join("\n");
+}
+
+void PasswordHealth::addScoreDetails(QString details)
+{
+    m_scoreDetails.append(details);
+}
+
+PasswordHealth::Quality PasswordHealth::quality() const
+{
+    if (m_score <= 0) {
+        return Quality::Bad;
+    } else if (m_score < 40) {
+        return Quality::Poor;
+    } else if (m_score < 65) {
+        return Quality::Weak;
+    } else if (m_score < 100) {
+        return Quality::Good;
+    }
+    return Quality::Excellent;
+}
+
+/**
+ * This class provides additional information about password health
+ * than can be derived from the password itself (re-use, expiry).
+ */
+HealthChecker::HealthChecker(QSharedPointer<Database> db)
+{
+    // Build the cache of re-used passwords
+    for (const auto* entry : db->rootGroup()->entriesRecursive()) {
+        if (!entry->isRecycled()) {
+            m_reuse[entry->password()]
+                << QApplication::tr("Used in %1/%2").arg(entry->group()->hierarchy().join('/'), entry->title());
+        }
+    }
+}
+
+/**
+ * Call operator of the Health Checker class.
+ *
+ * Returns the health of the password in `entry`, considering
+ * password entropy, re-use, expiration, etc.
+ */
+QSharedPointer<PasswordHealth> HealthChecker::evaluate(const Entry* entry) const
+{
+    // Pointer sanity check
+    if (!entry) {
+        return {};
+    }
+
+    // First analyse the password itself
+    const auto pwd = entry->password();
+    auto health = QSharedPointer<PasswordHealth>(new PasswordHealth(pwd));
+
+    // Second, if the password is in the database more than once,
+    // reduce the score accordingly
+    const auto& used = m_reuse[pwd];
+    const auto count = used.size();
+    if (count > 1) {
+        constexpr auto penalty = 15;
+        health->adjustScore(-penalty * (count - 1));
+        health->addScoreReason(QApplication::tr("Password is used %1 times").arg(QString::number(count)));
+        // Add the first 20 uses of the password to prevent the details display from growing too large
+        for (int i = 0; i < used.size(); ++i) {
+            health->addScoreDetails(used[i]);
+            if (i == 19) {
+                health->addScoreDetails(QStringLiteral("..."));
+                break;
+            }
+        }
+
+        // Don't allow re-used passwords to be considered "good"
+        // no matter how great their entropy is.
+        if (health->score() > 64) {
+            health->setScore(64);
+        }
+    }
+
+    // Third, if the password has already expired, reduce score to 0;
+    // or, if the password is going to expire in the next 30 days,
+    // reduce score by 2 points per day.
+    if (entry->isExpired()) {
+        health->setScore(0);
+        health->addScoreReason(QApplication::tr("Password has expired"));
+        health->addScoreDetails(QApplication::tr("Password expiry was %1")
+                                    .arg(entry->timeInfo().expiryTime().toString(Qt::DefaultLocaleShortDate)));
+    } else if (entry->timeInfo().expires()) {
+        const auto days = QDateTime::currentDateTime().daysTo(entry->timeInfo().expiryTime());
+        if (days <= 30) {
+            // First bring the score down into the "weak" range
+            // so that the entry appears in Health Check. Then
+            // reduce the score by 2 points for every day that
+            // we get closer to expiry. days<=0 has already
+            // been handled above ("isExpired()").
+            if (health->score() > 60) {
+                health->setScore(60);
+            }
+            health->adjustScore((30 - days) * -2);
+            health->addScoreReason(days <= 2 ? QApplication::tr("Password is about to expire")
+                                             : days <= 10 ? QApplication::tr("Password expires in %1 days").arg(days)
+                                                          : QApplication::tr("Password will expire soon"));
+            health->addScoreDetails(QApplication::tr("Password expires on %1")
+                                        .arg(entry->timeInfo().expiryTime().toString(Qt::DefaultLocaleShortDate)));
+        }
+    }
+
+    // Return the result
+    return health;
+}

src/core/PasswordHealth.h

@@ -0,0 +1,111 @@
+/*
+ *  Copyright (C) 2019 KeePassXC Team <[email protected]>
+ *
+ *  This program is free 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 2 or (at your option)
+ *  version 3 of the License.
+ *
+ *  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
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef KEEPASSX_PASSWORDHEALTH_H
+#define KEEPASSX_PASSWORDHEALTH_H
+
+#include <QHash>
+#include <QSharedPointer>
+#include <QStringList>
+
+class Database;
+class Entry;
+
+/**
+ * Health status of a single password.
+ *
+ * @see HealthChecker
+ */
+class PasswordHealth
+{
+public:
+    explicit PasswordHealth(double entropy);
+    explicit PasswordHealth(QString pwd);
+
+    /*
+     * The password score is defined to be the greater the better
+     * (more secure) the password is. It doesn't have a dimension,
+     * there are no defined maximum or minimum values, and score
+     * values may change with different versions of the software.
+     */
+    int score() const
+    {
+        return m_score;
+    }
+
+    void setScore(int score);
+    void adjustScore(int amount);
+
+    /*
+     * A text description for the password's quality assessment
+     * (translated into the application language), and additional
+     * information. Empty if nothing is wrong with the password.
+     * May contain more than line, separated by '\n'.
+     */
+    QString scoreReason() const;
+    void addScoreReason(QString reason);
+
+    QString scoreDetails() const;
+    void addScoreDetails(QString details);
+
+    /*
+     * The password quality assessment (based on the score).
+     */
+    enum class Quality
+    {
+        Bad,
+        Poor,
+        Weak,
+        Good,
+        Excellent
+    };
+    Quality quality() const;
+
+    /*
+     * The password's raw entropy value, in bits.
+     */
+    double entropy() const
+    {
+        return m_entropy;
+    }
+
+private:
+    int m_score = 0;
+    double m_entropy = 0.0;
+    QStringList m_scoreReasons;
+    QStringList m_scoreDetails;
+};
+
+/**
+ * Password health check for all entries of a database.
+ *
+ * @see PasswordHealth
+ */
+class HealthChecker
+{
+public:
+    explicit HealthChecker(QSharedPointer<Database>);
+
+    // Get the health status of an entry in the database
+    QSharedPointer<PasswordHealth> evaluate(const Entry* entry) const;
+
+private:
+    // To determine password re-use: first = password, second = entries that use it
+    QHash<QString, QStringList> m_reuse;
+};
+
+#endif // KEEPASSX_PASSWORDHEALTH_H