1 files changed, 81 insertions, 0 deletions
diff --git a/eaaf-springboot-utils/src/main/java/at/gv/egiz/eaaf/utils/springboot/utils/CachingPasswordEncoder.java b/eaaf-springboot-utils/src/main/java/at/gv/egiz/eaaf/utils/springboot/utils/CachingPasswordEncoder.java
new file mode 100644
index 00000000..672ebb5e
--- /dev/null
+++ b/eaaf-springboot-utils/src/main/java/at/gv/egiz/eaaf/utils/springboot/utils/CachingPasswordEncoder.java
@@ -0,0 +1,81 @@
+package at.gv.egiz.eaaf.utils.springboot.utils;
+
+import java.nio.charset.StandardCharsets;
+import java.security.MessageDigest;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+
+import org.springframework.security.crypto.password.PasswordEncoder;
+
+import lombok.AllArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+
+/**
+ * Decorator for {@link PasswordEncoder} that caches valid password to speed-up password verification.
+ * 
+ * @author tlenz
+ *
+ */
+@Slf4j
+@AllArgsConstructor
+public class CachingPasswordEncoder implements PasswordEncoder {
+
+  /**
+   * Cryptographic password encoder. 
+   */
+  private final PasswordEncoder internalEncoder;     
+  
+  /**
+   * Look-up table to speed-up password validation on REST API's.
+   */
+  private final Map<String, String> passwordCache = new ConcurrentHashMap<>(10);
+  
+  @Override
+  public String encode(CharSequence rawPassword) {
+    log.trace("Delegate password encoding to: {}", internalEncoder.getClass().getName());
+    return internalEncoder.encode(rawPassword);
+    
+  }
+
+  @Override
+  public boolean matches(CharSequence rawPassword, String encodedPassword) {
+    
+    if (passwordCache.containsKey(rawPassword.toString())) {
+      log.trace("Find password in cache. Starting verification ... ");
+      String cachedPassword = passwordCache.get(rawPassword).toString();
+      if (equalsNoEarlyReturn(cachedPassword, encodedPassword)) {        
+        return true;
+        
+      }
+    }
+    
+    return checkPasswordAndUpdateCache(rawPassword, encodedPassword);
+            
+  }
+  
+  @Override
+  public boolean upgradeEncoding(String encodedPassword) {
+    return internalEncoder.upgradeEncoding(encodedPassword);
+    
+  }
+  
+  
+  private boolean checkPasswordAndUpdateCache(CharSequence rawPassword, String encodedPassword) {
+    log.trace("Password not cached. Starting password processing ... ");
+    boolean passwordValid = internalEncoder.matches(rawPassword, encodedPassword);
+    if (passwordValid) {
+      log.debug("Get valid password. Cached it for faster reusage");
+      passwordCache.put(rawPassword.toString(), encodedPassword);
+      
+    } 
+    
+    return passwordValid;
+                
+  }
+
+  static boolean equalsNoEarlyReturn(String a, String b) {
+    return MessageDigest.isEqual(a.getBytes(StandardCharsets.UTF_8), b.getBytes(StandardCharsets.UTF_8));
+    
+  }
+
+}