1 files changed, 77 insertions, 0 deletions
diff --git a/gerrit-sshd/src/main/java/com/google/gerrit/sshd/HostKeyProvider.java b/gerrit-sshd/src/main/java/com/google/gerrit/sshd/HostKeyProvider.java
new file mode 100644
index 0000000000..db84cb79ac
--- /dev/null
+++ b/gerrit-sshd/src/main/java/com/google/gerrit/sshd/HostKeyProvider.java
@@ -0,0 +1,77 @@
+// Copyright (C) 2009 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.gerrit.server.config.SitePath;
+import com.google.inject.Inject;
+import com.google.inject.Provider;
+import com.google.inject.ProvisionException;
+
+import org.apache.sshd.common.KeyPairProvider;
+import org.apache.sshd.common.keyprovider.FileKeyPairProvider;
+import org.apache.sshd.common.util.SecurityUtils;
+import org.apache.sshd.server.keyprovider.SimpleGeneratorHostKeyProvider;
+
+import java.io.File;
+import java.util.ArrayList;
+import java.util.List;
+
+class HostKeyProvider implements Provider<KeyPairProvider> {
+  private final File sitePath;
+
+  @Inject
+  HostKeyProvider(@SitePath final File sitePath) {
+    this.sitePath = sitePath;
+  }
+
+  @Override
+  public KeyPairProvider get() {
+    final File anyKey = new File(sitePath, "ssh_host_key");
+    final File rsaKey = new File(sitePath, "ssh_host_rsa_key");
+    final File dsaKey = new File(sitePath, "ssh_host_dsa_key");
+
+    final List<String> keys = new ArrayList<String>(2);
+    if (rsaKey.exists()) {
+      keys.add(rsaKey.getAbsolutePath());
+    }
+    if (dsaKey.exists()) {
+      keys.add(dsaKey.getAbsolutePath());
+    }
+
+    if (anyKey.exists() && !keys.isEmpty()) {
+      // If both formats of host key exist, we don't know which format
+      // should be authoritative. Complain and abort.
+      //
+      keys.add(anyKey.getAbsolutePath());
+      throw new ProvisionException("Multiple host keys exist: " + keys);
+    }
+
+    if (keys.isEmpty()) {
+      // No administrator created host key? Generate and save our own.
+      //
+      final SimpleGeneratorHostKeyProvider keyp;
+
+      keyp = new SimpleGeneratorHostKeyProvider();
+      keyp.setPath(anyKey.getAbsolutePath());
+      return keyp;
+    }
+
+    if (!SecurityUtils.isBouncyCastleRegistered()) {
+      throw new ProvisionException("Bouncy Castle Crypto not installed;"
+          + " needed to read server host keys: " + keys + "");
+    }
+    return new FileKeyPairProvider(keys.toArray(new String[keys.size()]));
+  }
+}