1 files changed, 42 insertions, 0 deletions
diff --git a/java/com/google/gerrit/sshd/LogMaxConnectionsPerUserExceeded.java b/java/com/google/gerrit/sshd/LogMaxConnectionsPerUserExceeded.java
new file mode 100644
index 0000000000..6f568b1a5b
--- /dev/null
+++ b/java/com/google/gerrit/sshd/LogMaxConnectionsPerUserExceeded.java
@@ -0,0 +1,42 @@
+// Copyright (C) 2021 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.sshd;
+
+import com.google.common.flogger.FluentLogger;
+import com.google.inject.Singleton;
+import java.io.IOException;
+import org.apache.sshd.common.Service;
+import org.apache.sshd.common.session.Session;
+import org.apache.sshd.common.session.SessionDisconnectHandler;
+
+@Singleton
+public class LogMaxConnectionsPerUserExceeded implements SessionDisconnectHandler {
+  private static final FluentLogger logger = FluentLogger.forEnclosingClass();
+
+  @Override
+  public boolean handleSessionsCountDisconnectReason(
+      Session session,
+      Service service,
+      String username,
+      int currentSessionCount,
+      int maxSessionCount)
+      throws IOException {
+    logger.atWarning().log(
+        "Max connection count for user %s exceeded, rejecting new connection."
+            + " currentSessionCount = %d, maxSessionCount = %d",
+        username, currentSessionCount, maxSessionCount);
+    return false;
+  }
+}