#930 Create registration captcha manager

- Introduce registration captcha manager, rename login captcha manager accordingly
- Integrate reg. captcha manager into /register command

Open points:
- Refactor common captcha functionality into abstract superclass
- If captcha before /register necessary, show appropriate message to player immediately
- Unit tests

src/main/java/fr/xephi/authme/data/LoginCaptchaManager.java

@@ -12,9 +12,9 @@ import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.TimeUnit;
 
 /**
- * Manager for the handling of captchas.
+ * Manager for the handling of captchas after too many failed login attempts.
  */
-public class CaptchaManager implements SettingsDependent, HasCleanup {
+public class LoginCaptchaManager implements SettingsDependent, HasCleanup {
 
     private final TimedCounter<String> playerCounts;
     private final ConcurrentHashMap<String, String> captchaCodes;
@@ -24,7 +24,7 @@ public class CaptchaManager implements SettingsDependent, HasCleanup {
     private int captchaLength;
 
     @Inject
-    CaptchaManager(Settings settings) {
+    LoginCaptchaManager(Settings settings) {
         this.captchaCodes = new ConcurrentHashMap<>();
         long countTimeout = settings.getProperty(SecuritySettings.CAPTCHA_COUNT_MINUTES_BEFORE_RESET);
         this.playerCounts = new TimedCounter<>(countTimeout, TimeUnit.MINUTES);
@@ -36,7 +36,7 @@ public class CaptchaManager implements SettingsDependent, HasCleanup {
      *
      * @param name the player's name
      */
-    public void increaseCount(String name) {
+    public void increaseLoginFailureCount(String name) {
         if (isEnabled) {
             String playerLower = name.toLowerCase();
             playerCounts.increment(playerLower);
@@ -44,7 +44,7 @@ public class CaptchaManager implements SettingsDependent, HasCleanup {
     }
 
     /**
-     * Returns whether the given player is required to solve a captcha.
+     * Returns whether the given player is required to solve a captcha before he can use /login again.
      *
      * @param name the name of the player to verify
      * @return true if the player has to solve a captcha, false otherwise
@@ -84,12 +84,13 @@ public class CaptchaManager implements SettingsDependent, HasCleanup {
      * @return true if the code matches or if no captcha is required for the player, false otherwise
      */
     public boolean checkCode(String name, String code) {
-        String savedCode = captchaCodes.get(name.toLowerCase());
+        final String nameLowerCase = name.toLowerCase();
+        String savedCode = captchaCodes.get(nameLowerCase);
         if (savedCode == null) {
             return true;
         } else if (savedCode.equalsIgnoreCase(code)) {
-            captchaCodes.remove(name.toLowerCase());
-            playerCounts.remove(name.toLowerCase());
+            captchaCodes.remove(nameLowerCase);
+            playerCounts.remove(nameLowerCase);
             return true;
         }
         return false;
@@ -100,7 +101,7 @@ public class CaptchaManager implements SettingsDependent, HasCleanup {
      *
      * @param name the player's name
      */
-    public void resetCounts(String name) {
+    public void resetLoginFailureCount(String name) {
         if (isEnabled) {
             captchaCodes.remove(name.toLowerCase());
             playerCounts.remove(name.toLowerCase());
@@ -109,7 +110,7 @@ public class CaptchaManager implements SettingsDependent, HasCleanup {
 
     @Override
     public void reload(Settings settings) {
-        this.isEnabled = settings.getProperty(SecuritySettings.USE_CAPTCHA);
+        this.isEnabled = settings.getProperty(SecuritySettings.ENABLE_LOGIN_FAILURE_CAPTCHA);
         this.threshold = settings.getProperty(SecuritySettings.MAX_LOGIN_TRIES_BEFORE_CAPTCHA);
         this.captchaLength = settings.getProperty(SecuritySettings.CAPTCHA_LENGTH);
         long countTimeout = settings.getProperty(SecuritySettings.CAPTCHA_COUNT_MINUTES_BEFORE_RESET);

src/main/java/fr/xephi/authme/data/RegistrationCaptchaManager.java

@@ -0,0 +1,98 @@
+package fr.xephi.authme.data;
+
+import fr.xephi.authme.initialization.HasCleanup;
+import fr.xephi.authme.initialization.SettingsDependent;
+import fr.xephi.authme.settings.Settings;
+import fr.xephi.authme.settings.properties.SecuritySettings;
+import fr.xephi.authme.util.RandomStringUtils;
+import fr.xephi.authme.util.expiring.ExpiringSet;
+
+import javax.inject.Inject;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * Captcha handler for registration.
+ */
+public class RegistrationCaptchaManager implements SettingsDependent, HasCleanup {
+
+    private static final int MINUTES_VALID_FOR_REGISTRATION = 30;
+
+    private final Map<String, String> captchaCodes;
+    private final ExpiringSet<String> verifiedNamesForRegistration;
+
+    private boolean isEnabledForRegistration;
+    private int captchaLength;
+
+    @Inject
+    RegistrationCaptchaManager(Settings settings) {
+        this.captchaCodes = new ConcurrentHashMap<>();
+        this.verifiedNamesForRegistration = new ExpiringSet<>(MINUTES_VALID_FOR_REGISTRATION, TimeUnit.MINUTES);
+        reload(settings);
+    }
+
+    /**
+     * Returns whether the given player is required to solve a captcha before he can register.
+     *
+     * @param name the name of the player to verify
+     * @return true if the player has to solve a captcha, false otherwise
+     */
+    public boolean isCaptchaRequired(String name) {
+        return isEnabledForRegistration && !verifiedNamesForRegistration.contains(name.toLowerCase());
+    }
+
+    /**
+     * Returns the stored captcha for the player or generates and saves a new one.
+     *
+     * @param name the player's name
+     * @return the code the player is required to enter
+     */
+    public String getCaptchaCodeOrGenerateNew(String name) {
+        String code = captchaCodes.get(name.toLowerCase());
+        return code == null ? generateCode(name) : code;
+    }
+
+    /**
+     * Generates a code for the player and returns it.
+     *
+     * @param name the name of the player to generate a code for
+     * @return the generated code
+     */
+    public String generateCode(String name) {
+        String code = RandomStringUtils.generate(captchaLength);
+        captchaCodes.put(name.toLowerCase(), code);
+        return code;
+    }
+
+    /**
+     * Checks the given code against the existing one and resets the player's auth failure count upon success.
+     *
+     * @param name the name of the player to check
+     * @param code the supplied code
+     * @return true if the code matches or if no captcha is required for the player, false otherwise
+     */
+    public boolean checkCode(String name, String code) {
+        final String nameLowerCase = name.toLowerCase();
+        String savedCode = captchaCodes.get(nameLowerCase);
+        if (savedCode == null) {
+            return true;
+        } else if (savedCode.equalsIgnoreCase(code)) {
+            captchaCodes.remove(nameLowerCase);
+            verifiedNamesForRegistration.add(nameLowerCase);
+            return true;
+        }
+        return false;
+    }
+
+    @Override
+    public void reload(Settings settings) {
+        this.isEnabledForRegistration = settings.getProperty(SecuritySettings.ENABLE_CAPTCHA_FOR_REGISTRATION);
+        this.captchaLength = settings.getProperty(SecuritySettings.CAPTCHA_LENGTH);
+    }
+
+    @Override
+    public void performCleanup() {
+        verifiedNamesForRegistration.removeExpiredEntries();
+    }
+}