GUACAMOLE-5: Add randomly-generated connection sharing keys.

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/apache/guacamole/auth/jdbc/JDBCAuthenticationProviderModule.java

@@ -19,6 +19,7 @@
 
 package org.apache.guacamole.auth.jdbc;
 
+import com.google.inject.Scopes;
 import org.apache.guacamole.auth.jdbc.user.UserContext;
 import org.apache.guacamole.auth.jdbc.connectiongroup.RootConnectionGroup;
 import org.apache.guacamole.auth.jdbc.connectiongroup.ModeledConnectionGroup;
@@ -62,6 +63,8 @@ import org.apache.guacamole.auth.jdbc.connection.ConnectionParameterMapper;
 import org.apache.guacamole.auth.jdbc.permission.SharingProfilePermissionMapper;
 import org.apache.guacamole.auth.jdbc.permission.SharingProfilePermissionService;
 import org.apache.guacamole.auth.jdbc.permission.SharingProfilePermissionSet;
+import org.apache.guacamole.auth.jdbc.sharing.SecureRandomShareKeyGenerator;
+import org.apache.guacamole.auth.jdbc.sharing.ShareKeyGenerator;
 import org.apache.guacamole.auth.jdbc.sharingprofile.ModeledSharingProfile;
 import org.apache.guacamole.auth.jdbc.sharingprofile.SharingProfileDirectory;
 import org.apache.guacamole.auth.jdbc.sharingprofile.SharingProfileMapper;
@@ -167,6 +170,7 @@ public class JDBCAuthenticationProviderModule extends MyBatisModule {
         bind(GuacamoleTunnelService.class).to(RestrictedGuacamoleTunnelService.class);
         bind(PasswordEncryptionService.class).to(SHA256PasswordEncryptionService.class);
         bind(SaltService.class).to(SecureRandomSaltService.class);
+        bind(ShareKeyGenerator.class).to(SecureRandomShareKeyGenerator.class).in(Scopes.SINGLETON);
         bind(SharingProfilePermissionService.class);
         bind(SharingProfileService.class);
         bind(SystemPermissionService.class);

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/apache/guacamole/auth/jdbc/sharing/SecureRandomShareKeyGenerator.java

@@ -0,0 +1,45 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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 org.apache.guacamole.auth.jdbc.sharing;
+
+import java.security.SecureRandom;
+import javax.xml.bind.DatatypeConverter;
+
+/**
+ * An implementation of the ShareKeyGenerator which uses SecureRandom to
+ * generate cryptographically-secure random sharing keys.
+ * 
+ * @author Michael Jumper
+ */
+public class SecureRandomShareKeyGenerator implements ShareKeyGenerator {
+
+    /**
+     * Instance of SecureRandom for generating sharing keys.
+     */
+    private final SecureRandom secureRandom = new SecureRandom();
+
+    @Override
+    public String getShareKey() {
+        byte[] bytes = new byte[33];
+        secureRandom.nextBytes(bytes);
+        return DatatypeConverter.printBase64Binary(bytes);
+    }
+
+}

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/apache/guacamole/auth/jdbc/sharing/ShareKeyGenerator.java

@@ -0,0 +1,39 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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 org.apache.guacamole.auth.jdbc.sharing;
+
+/**
+ * Produces unique keys that can be safely used for the automatically-generated
+ * "sharing credentials" associated with a shared connection.
+ * 
+ * @author Michael Jumper
+ */
+public interface ShareKeyGenerator {
+    
+    /**
+     * Returns a new share key, guaranteed to be unique from all previously-
+     * returned share keys.
+     * 
+     * @return
+     *     The new share key.
+     */
+    public String getShareKey();
+
+}