ZOOKEEPER-5049: Redact passwords from PrometheusMetricsProvider configuration logging

zookeeper-metrics-providers/zookeeper-prometheus-metrics/src/main/java/org/apache/zookeeper/metrics/prometheus/PrometheusMetricsProvider.java

@@ -25,6 +25,7 @@
 import java.io.IOException;
 import java.security.GeneralSecurityException;
 import java.security.KeyStore;
+import java.util.Locale;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Properties;
@@ -136,7 +137,7 @@ protected void doTrace(HttpServletRequest req, HttpServletResponse resp) throws
 
     @Override
     public void configure(Properties configuration) throws MetricsProviderLifeCycleException {
-        LOG.info("Initializing Prometheus metrics with Jetty, configuration: {}", configuration);
+        LOG.info("Initializing Prometheus metrics with Jetty, configuration: {}", redactSensitiveValues(configuration));
 
         this.host = configuration.getProperty(HTTP_HOST, "0.0.0.0");
         this.httpPort = Integer.parseInt(configuration.getProperty(HTTP_PORT, "-1"));
@@ -528,13 +529,13 @@ public SummarySet getSummarySet(String name, DetailLevel detailLevel) {
                 return new PrometheusLabelledSummaryWrapper(prometheusSummary);
             });
         }
+
     }
 
     // --- Wrapper classes to adapt Prometheus metrics to ZooKeeper's metric interfaces ---
-
     private static class PrometheusCounterWrapper implements Counter {
-        private final io.prometheus.metrics.core.metrics.Counter prometheusCounter;
 
+        private final io.prometheus.metrics.core.metrics.Counter prometheusCounter;
         public PrometheusCounterWrapper(io.prometheus.metrics.core.metrics.Counter prometheusCounter) {
             this.prometheusCounter = prometheusCounter;
         }
@@ -602,4 +603,20 @@ public void add(String key, long value) {
             this.prometheusSummary.labelValues(key).observe(value);
         }
     }
+
+    private static Properties redactSensitiveValues(Properties configuration) {
+        Properties redactedConfig = new Properties();
+        configuration.forEach((k, v) -> redactedConfig.put(k, logRedactor((String) k, (String) v)));
+        return redactedConfig;
+    }
+
+    private static String logRedactor(String key, String value) {
+        if (key == null) {
+            return value;
+        }
+        if (key.toLowerCase(Locale.ROOT).endsWith("password")) {
+            return "***";
+        }
+        return value;
+    }
 }

zookeeper-metrics-providers/zookeeper-prometheus-metrics/src/test/java/org/apache/zookeeper/metrics/prometheus/PrometheusHttpsMetricsProviderTest.java

@@ -21,6 +21,11 @@
 import static org.hamcrest.CoreMatchers.containsString;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import ch.qos.logback.classic.Logger;
+import ch.qos.logback.classic.spi.ILoggingEvent;
+import ch.qos.logback.core.read.ListAppender;
 import java.io.BufferedReader;
 import java.io.FileInputStream;
 import java.io.IOException;
@@ -36,6 +41,7 @@
 import org.apache.zookeeper.metrics.Counter;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.Test;
+import org.slf4j.LoggerFactory;
 
 /**
  * Tests about Prometheus Metrics Provider. Please note that we are not testing Prometheus but only our integration.
@@ -176,4 +182,39 @@ private void validateMetricResponse(String response) throws IOException {
         assertThat(response, containsString("# TYPE cc_total counter"));
         assertThat(response, containsString("cc_total 10.0"));
     }
+
+    @Test
+    void testLogRedactorRedactsPasswords() throws Exception {
+        Logger logger = (Logger) LoggerFactory.getLogger(PrometheusMetricsProvider.class);
+        ListAppender<ILoggingEvent> listAppender = new ListAppender<>();
+        listAppender.start();
+        logger.addAppender(listAppender);
+
+        try {
+            provider = new PrometheusMetricsProvider();
+            Properties configuration = new Properties();
+            configuration.setProperty("httpPort", String.valueOf(httpPort));
+            configuration.setProperty("httpsPort", String.valueOf(httpsPort));
+            configuration.setProperty("ssl.keyStore.location", testDataPath + "/ssl/server_keystore.jks");
+            configuration.setProperty("ssl.keyStore.password", "SuperSecret123!");
+            configuration.setProperty("ssl.trustStore.location", testDataPath + "/ssl/server_truststore.jks");
+            configuration.setProperty("ssl.trustStore.password", "AnotherSecret456!");
+            provider.configure(configuration);
+
+            String logOutput = listAppender.list.stream()
+                    .map(ILoggingEvent::getFormattedMessage)
+                    .filter(msg -> msg.contains("configuration"))
+                    .findFirst()
+                    .orElse("");
+
+            assertFalse(logOutput.contains("SuperSecret123!"),
+                    "Logs should not contain keyStore password");
+            assertFalse(logOutput.contains("AnotherSecret456!"),
+                    "Logs should not contain trustStore password");
+            assertTrue(logOutput.contains(testDataPath + "/ssl/server_keystore.jks"),
+                    "Logs should still contain non-sensitive config like keyStore location");
+        } finally {
+            logger.detachAppender(listAppender);
+        }
+    }
 }