/* * Copyright 2012-2015 org.opencloudb. * * 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 org.opencloudb.server.handler; import java.nio.ByteBuffer; import java.util.Set; import org.opencloudb.config.ErrorCode; import org.opencloudb.net.handler.FrontendPrivileges; import org.opencloudb.net.mysql.OkPacket; import org.opencloudb.server.ServerConnection; import org.opencloudb.util.StringUtil; /** * @author mycat */ public final class UseHandler { public static void handle(String sql, ServerConnection c, int offset) { String schema = sql.substring(offset).trim(); int length = schema.length(); if (length > 0) { if(schema.endsWith(";")) schema=schema.substring(0,schema.length()-1); schema = StringUtil.replaceChars(schema, "`", null); length=schema.length(); if (schema.charAt(0) == '\'' && schema.charAt(length - 1) == '\'') { schema = schema.substring(1, length - 1); } } // 表示当前连接已经指定了schema if (c.getSchema() != null) { if (c.getSchema().equals(schema)) { ByteBuffer buffer = c.allocate(); c.write(c.writeToBuffer(OkPacket.OK, buffer)); } else { c.writeErrMessage(ErrorCode.ER_DBACCESS_DENIED_ERROR, "Not allowed to change the database!"); } return; } // 检查schema的有效性 FrontendPrivileges privileges = c.getPrivileges(); if (schema == null || !privileges.schemaExists(schema)) { c.writeErrMessage(ErrorCode.ER_BAD_DB_ERROR, "Unknown database '" + schema + "'"); return; } String user = c.getUser(); if (!privileges.userExists(user, c.getHost())) { c.writeErrMessage(ErrorCode.ER_ACCESS_DENIED_ERROR, "Access denied for user '" + c.getUser() + "'"); return; } Set<String> schemas = privileges.getUserSchemas(user); if (schemas == null || schemas.size() == 0 || schemas.contains(schema)) { c.setSchema(schema); ByteBuffer buffer = c.allocate(); c.write(c.writeToBuffer(OkPacket.OK, buffer)); } else { String msg = "Access denied for user '" + c.getUser() + "' to database '" + schema + "'"; c.writeErrMessage(ErrorCode.ER_DBACCESS_DENIED_ERROR, msg); } } }