Java tutorial
/******************************************************************************* * This file is part of OpenNMS(R). * * Copyright (C) 2012 The OpenNMS Group, Inc. * OpenNMS(R) is Copyright (C) 1999-2012 The OpenNMS Group, Inc. * * OpenNMS(R) is a registered trademark of The OpenNMS Group, Inc. * * OpenNMS(R) is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published * by the Free Software Foundation, either version 3 of the License, * or (at your option) any later version. * * OpenNMS(R) is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with OpenNMS(R). If not, see: * http://www.gnu.org/licenses/ * * For more information contact: * OpenNMS(R) Licensing <license@opennms.org> * http://www.opennms.org/ * http://www.opennms.com/ *******************************************************************************/ package com.netxforge.oss2.config; import java.io.File; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStreamWriter; import java.io.Reader; import java.io.StringWriter; import java.io.UnsupportedEncodingException; import java.io.Writer; import java.net.InetAddress; import java.util.concurrent.locks.Lock; import java.util.concurrent.locks.ReadWriteLock; import java.util.concurrent.locks.ReentrantReadWriteLock; import org.apache.commons.io.IOUtils; import org.opennms.core.utils.ByteArrayComparator; import org.opennms.core.utils.ConfigFileConstants; import org.opennms.core.utils.IPLike; import org.opennms.core.utils.InetAddressUtils; import org.opennms.core.utils.LogUtils; import org.opennms.core.xml.JaxbUtils; import org.opennms.netmgt.config.snmp.Definition; import org.opennms.netmgt.config.snmp.Range; import org.opennms.netmgt.config.snmp.SnmpConfig; import org.opennms.netmgt.snmp.SnmpAgentConfig; import org.springframework.core.io.FileSystemResource; import org.springframework.core.io.Resource; import org.xml.sax.InputSource; /** * This class is the main repository for SNMP configuration information used by * the capabilities daemon. When this class is loaded it reads the snmp * configuration into memory, and uses the configuration to find the * {@link org.opennms.netmgt.snmp.SnmpAgentConfig SnmpAgentConfig} objects for specific * addresses. If an address cannot be located in the configuration then a * default peer instance is returned to the caller. * * <strong>Note: </strong>Users of this class should make sure the * <em>init()</em> is called before calling any other method to ensure the * config is loaded before accessing other convenience methods. * * @author <a href="mailto:david@opennms.org">David Hustace</a> * @author <a href="mailto:weave@oculan.com">Weave</a> * @author <a href="mailto:gturner@newedgenetworks.com">Gerald Turner</a> */ public class SnmpPeerFactory implements SnmpAgentConfigFactory { private static final int DEFAULT_SNMP_PORT = 161; private static final ReadWriteLock m_globalLock = new ReentrantReadWriteLock(); private static final Lock m_readLock = m_globalLock.readLock(); private static final Lock m_writeLock = m_globalLock.writeLock(); /** * The singleton instance of this factory */ private static SnmpPeerFactory m_singleton = null; /** * The config class loaded from the config file */ private static SnmpConfig m_config; private static File m_configFile; /** * This member is set to true if the configuration file has been loaded. */ private static boolean m_loaded = false; private static final int VERSION_UNSPECIFIED = -1; /** * Private constructor * * @exception java.io.IOException * Thrown if the specified config file cannot be read * @exception org.exolab.castor.xml.MarshalException * Thrown if the file does not conform to the schema. * @exception org.exolab.castor.xml.ValidationException * Thrown if the contents do not match the required schema. */ private SnmpPeerFactory(final File configFile) throws IOException { this(new FileSystemResource(configFile)); } /** * <p>Constructor for SnmpPeerFactory.</p> * * @param resource a {@link org.springframework.core.io.Resource} object. */ public SnmpPeerFactory(final Resource resource) { SnmpPeerFactory.getWriteLock().lock(); try { m_config = JaxbUtils.unmarshal(SnmpConfig.class, resource); } finally { SnmpPeerFactory.getWriteLock().unlock(); } } /** * <p>Constructor for SnmpPeerFactory.</p> * * @param rdr a {@link java.io.Reader} object. * @throws java.io.IOException if any. * @throws org.exolab.castor.xml.MarshalException if any. * @throws org.exolab.castor.xml.ValidationException if any. * @deprecated Use code for InputStream instead to avoid character set issues */ public SnmpPeerFactory(final Reader rdr) throws IOException { SnmpPeerFactory.getWriteLock().lock(); try { m_config = JaxbUtils.unmarshal(SnmpConfig.class, rdr); } finally { SnmpPeerFactory.getWriteLock().unlock(); } } /** * A constructor that takes a config string for use mostly in tests */ public SnmpPeerFactory(final String configString) throws IOException { SnmpPeerFactory.getWriteLock().lock(); try { m_config = JaxbUtils.unmarshal(SnmpConfig.class, configString); } finally { SnmpPeerFactory.getWriteLock().unlock(); } } /** * <p>Constructor for SnmpPeerFactory.</p> * * @param stream a {@link java.io.InputStream} object. */ public SnmpPeerFactory(final InputStream stream) { SnmpPeerFactory.getWriteLock().lock(); try { m_config = JaxbUtils.unmarshal(SnmpConfig.class, new InputSource(stream), null); } finally { SnmpPeerFactory.getWriteLock().unlock(); } } public static Lock getReadLock() { return m_readLock; } public static Lock getWriteLock() { return m_writeLock; } /** * Load the config from the default config file and create the singleton * instance of this factory. * * @exception java.io.IOException * Thrown if the specified config file cannot be read * @exception org.exolab.castor.xml.MarshalException * Thrown if the file does not conform to the schema. * @exception org.exolab.castor.xml.ValidationException * Thrown if the contents do not match the required schema. * @throws java.io.IOException if any. * @throws org.exolab.castor.xml.MarshalException if any. * @throws org.exolab.castor.xml.ValidationException if any. */ public static void init() throws IOException { SnmpPeerFactory.getWriteLock().lock(); try { if (m_loaded) { // init already called - return // to reload, reload() will need to be called return; } final File cfgFile = getFile(); LogUtils.debugf(SnmpPeerFactory.class, "init: config file path: %s", cfgFile.getPath()); m_singleton = new SnmpPeerFactory(cfgFile); m_loaded = true; } finally { SnmpPeerFactory.getWriteLock().unlock(); } } /** * Saves the current settings to disk * * @throws java.io.IOException if any. * @throws org.exolab.castor.xml.MarshalException if any. * @throws org.exolab.castor.xml.ValidationException if any. */ public static void saveCurrent() throws IOException { saveToFile(getFile()); } public static void saveToFile(final File file) throws UnsupportedEncodingException, FileNotFoundException, IOException { // Marshal to a string first, then write the string to the file. This // way the original config // isn't lost if the XML from the marshal is hosed. final String marshalledConfig = marshallConfig(); SnmpPeerFactory.getWriteLock().lock(); FileOutputStream out = null; Writer fileWriter = null; try { if (marshalledConfig != null) { out = new FileOutputStream(file); fileWriter = new OutputStreamWriter(out, "UTF-8"); fileWriter.write(marshalledConfig); fileWriter.flush(); fileWriter.close(); } } finally { IOUtils.closeQuietly(fileWriter); IOUtils.closeQuietly(out); SnmpPeerFactory.getWriteLock().unlock(); } } /** * Return the singleton instance of this factory. * * @return The current factory instance. * @throws java.lang.IllegalStateException * Thrown if the factory has not yet been initialized. */ public static SnmpPeerFactory getInstance() { SnmpPeerFactory.getReadLock().lock(); try { if (!m_loaded) { throw new IllegalStateException("The factory has not been initialized"); } return m_singleton; } finally { SnmpPeerFactory.getReadLock().unlock(); } } /** * <p>setFile</p> * * @param configFile a {@link java.io.File} object. */ public static void setFile(final File configFile) { SnmpPeerFactory.getWriteLock().lock(); try { final File oldFile = m_configFile; m_configFile = configFile; // if the file changed then we need to reload the config if (oldFile == null || m_configFile == null || !oldFile.equals(m_configFile)) { m_singleton = null; m_loaded = false; } } finally { SnmpPeerFactory.getWriteLock().unlock(); } } /** * <p>getFile</p> * * @return a {@link java.io.File} object. * @throws java.io.IOException if any. */ public static File getFile() throws IOException { SnmpPeerFactory.getReadLock().lock(); try { if (m_configFile == null) { setFile(ConfigFileConstants.getFile(ConfigFileConstants.SNMP_CONF_FILE_NAME)); } return m_configFile; } finally { SnmpPeerFactory.getReadLock().unlock(); } } /** * <p>setInstance</p> * * @param singleton a {@link org.opennms.netmgt.config.SnmpPeerFactory} object. */ public static void setInstance(final SnmpPeerFactory singleton) { SnmpPeerFactory.getWriteLock().lock(); try { m_singleton = singleton; m_loaded = true; } finally { SnmpPeerFactory.getWriteLock().unlock(); } } /** {@inheritDoc} */ public SnmpAgentConfig getAgentConfig(final InetAddress agentAddress) { return getAgentConfig(agentAddress, VERSION_UNSPECIFIED); } private SnmpAgentConfig getAgentConfig(final InetAddress agentInetAddress, final int requestedSnmpVersion) { SnmpPeerFactory.getReadLock().lock(); try { if (m_config == null) { final SnmpAgentConfig agentConfig = new SnmpAgentConfig(agentInetAddress); if (requestedSnmpVersion == VERSION_UNSPECIFIED) { agentConfig.setVersion(SnmpAgentConfig.DEFAULT_VERSION); } else { agentConfig.setVersion(requestedSnmpVersion); } return agentConfig; } final SnmpAgentConfig agentConfig = new SnmpAgentConfig(agentInetAddress); // Now set the defaults from the m_config setSnmpAgentConfig(agentConfig, new Definition(), requestedSnmpVersion); // Attempt to locate the node DEFLOOP: for (final Definition def : m_config.getDefinitionCollection()) { // check the specifics first for (final String saddr : def.getSpecificCollection()) { try { final InetAddress addr = InetAddressUtils.addr(saddr); if (addr != null && addr.equals(agentConfig.getAddress())) { setSnmpAgentConfig(agentConfig, def, requestedSnmpVersion); break DEFLOOP; } } catch (final IllegalArgumentException e) { LogUtils.debugf(this, e, "Error while reading SNMP config <specific> tag: %s", saddr); } } // check the ranges // final ByteArrayComparator comparator = new ByteArrayComparator(); for (final Range rng : def.getRangeCollection()) { final byte[] addr = agentConfig.getAddress().getAddress(); final byte[] begin = InetAddressUtils.toIpAddrBytes(rng.getBegin()); final byte[] end = InetAddressUtils.toIpAddrBytes(rng.getEnd()); boolean inRange = InetAddressUtils.isInetAddressInRange(addr, begin, end); if (comparator.compare(begin, end) <= 0) { inRange = InetAddressUtils.isInetAddressInRange(addr, begin, end); } else { LogUtils.warnf(this, "%s has an 'end' that is earlier than its 'beginning'!", rng); inRange = InetAddressUtils.isInetAddressInRange(addr, end, begin); } if (inRange) { setSnmpAgentConfig(agentConfig, def, requestedSnmpVersion); break DEFLOOP; } } // check the matching ip expressions for (final String ipMatch : def.getIpMatchCollection()) { if (IPLike.matches(agentInetAddress, ipMatch)) { setSnmpAgentConfig(agentConfig, def, requestedSnmpVersion); break DEFLOOP; } } } // end DEFLOOP if (agentConfig == null) { final Definition def = new Definition(); setSnmpAgentConfig(agentConfig, def, requestedSnmpVersion); } return agentConfig; } finally { SnmpPeerFactory.getReadLock().unlock(); } } private void setSnmpAgentConfig(final SnmpAgentConfig agentConfig, final Definition def, final int requestedSnmpVersion) { int version = determineVersion(def, requestedSnmpVersion); setCommonAttributes(agentConfig, def, version); agentConfig.setSecurityLevel(determineSecurityLevel(def)); agentConfig.setSecurityName(determineSecurityName(def)); agentConfig.setAuthProtocol(determineAuthProtocol(def)); agentConfig.setAuthPassPhrase(determineAuthPassPhrase(def)); agentConfig.setPrivPassPhrase(determinePrivPassPhrase(def)); agentConfig.setPrivProtocol(determinePrivProtocol(def)); agentConfig.setReadCommunity(determineReadCommunity(def)); agentConfig.setWriteCommunity(determineWriteCommunity(def)); } /** * This is a helper method to set all the common attributes in the agentConfig. * * @param agentConfig * @param def * @param version */ private void setCommonAttributes(final SnmpAgentConfig agentConfig, final Definition def, final int version) { agentConfig.setVersion(version); agentConfig.setPort(determinePort(def)); agentConfig.setRetries(determineRetries(def)); agentConfig.setTimeout((int) determineTimeout(def)); agentConfig.setMaxRequestSize(determineMaxRequestSize(def)); agentConfig.setMaxVarsPerPdu(determineMaxVarsPerPdu(def)); agentConfig.setMaxRepetitions(determineMaxRepetitions(def)); InetAddress proxyHost = determineProxyHost(def); if (proxyHost != null) { agentConfig.setProxyFor(agentConfig.getAddress()); agentConfig.setAddress(determineProxyHost(def)); } } private int determineMaxRepetitions(final Definition def) { return (!def.hasMaxRepetitions() ? (!m_config.hasMaxRepetitions() ? SnmpAgentConfig.DEFAULT_MAX_REPETITIONS : m_config.getMaxRepetitions()) : def.getMaxRepetitions()); } private InetAddress determineProxyHost(final Definition def) { InetAddress inetAddr = null; final String address = def.getProxyHost() == null ? (m_config.getProxyHost() == null ? null : m_config.getProxyHost()) : def.getProxyHost(); if (address != null) { try { inetAddr = InetAddressUtils.addr(address); } catch (final IllegalArgumentException e) { LogUtils.debugf(this, e, "Error while reading SNMP config proxy host: %s", address); } } return inetAddr; } private int determineMaxVarsPerPdu(final Definition def) { return (!def.hasMaxVarsPerPdu() ? (!m_config.hasMaxVarsPerPdu() ? SnmpAgentConfig.DEFAULT_MAX_VARS_PER_PDU : m_config.getMaxVarsPerPdu()) : def.getMaxVarsPerPdu()); } /** * Helper method to search the snmp-config for the appropriate read * community string. * @param def * @return */ private String determineReadCommunity(final Definition def) { return (def.getReadCommunity() == null ? (m_config.getReadCommunity() == null ? SnmpAgentConfig.DEFAULT_READ_COMMUNITY : m_config.getReadCommunity()) : def.getReadCommunity()); } /** * Helper method to search the snmp-config for the appropriate write * community string. * @param def * @return */ private String determineWriteCommunity(final Definition def) { return (def.getWriteCommunity() == null ? (m_config.getWriteCommunity() == null ? SnmpAgentConfig.DEFAULT_WRITE_COMMUNITY : m_config.getWriteCommunity()) : def.getWriteCommunity()); } /** * Helper method to search the snmp-config for the appropriate maximum * request size. The default is the minimum necessary for a request. * @param def * @return */ private int determineMaxRequestSize(final Definition def) { return (!def.hasMaxRequestSize() ? (!m_config.hasMaxRequestSize() ? SnmpAgentConfig.DEFAULT_MAX_REQUEST_SIZE : m_config.getMaxRequestSize()) : def.getMaxRequestSize()); } /** * Helper method to find a security name to use in the snmp-config. If v3 has * been specified and one can't be found, then a default is used for this * is a required option for v3 operations. * @param def * @return */ private String determineSecurityName(final Definition def) { final String securityName = (def.getSecurityName() == null ? m_config.getSecurityName() : def.getSecurityName()); if (securityName == null) { return SnmpAgentConfig.DEFAULT_SECURITY_NAME; } return securityName; } /** * Helper method to find a security name to use in the snmp-config. If v3 has * been specified and one can't be found, then a default is used for this * is a required option for v3 operations. * @param def * @return */ private String determineAuthProtocol(final Definition def) { final String authProtocol = (def.getAuthProtocol() == null ? m_config.getAuthProtocol() : def.getAuthProtocol()); if (authProtocol == null) { return SnmpAgentConfig.DEFAULT_AUTH_PROTOCOL; } return authProtocol; } /** * Helper method to find a authentication passphrase to use from the snmp-config. If v3 has * been specified and one can't be found, then a default is used for this * is a required option for v3 operations. * @param def * @return */ private String determineAuthPassPhrase(final Definition def) { final String authPassPhrase = (def.getAuthPassphrase() == null ? m_config.getAuthPassphrase() : def.getAuthPassphrase()); if (authPassPhrase == null) { return SnmpAgentConfig.DEFAULT_AUTH_PASS_PHRASE; } return authPassPhrase; } /** * Helper method to find a privacy passphrase to use from the snmp-config. If v3 has * been specified and one can't be found, then a default is used for this * is a required option for v3 operations. * @param def * @return */ private String determinePrivPassPhrase(final Definition def) { final String privPassPhrase = (def.getPrivacyPassphrase() == null ? m_config.getPrivacyPassphrase() : def.getPrivacyPassphrase()); if (privPassPhrase == null) { return SnmpAgentConfig.DEFAULT_PRIV_PASS_PHRASE; } return privPassPhrase; } /** * Helper method to find a privacy protocol to use from the snmp-config. If v3 has * been specified and one can't be found, then a default is used for this * is a required option for v3 operations. * @param def * @return */ private String determinePrivProtocol(final Definition def) { final String authPrivProtocol = (def.getPrivacyProtocol() == null ? m_config.getPrivacyProtocol() : def.getPrivacyProtocol()); if (authPrivProtocol == null) { return SnmpAgentConfig.DEFAULT_PRIV_PROTOCOL; } return authPrivProtocol; } /** * Helper method to set the security level in v3 operations. The default is * noAuthNoPriv if there is no authentication passphrase. From there, if * there is a privacy passphrase supplied, then the security level is set to * authPriv else it falls out to authNoPriv. There are only these 3 possible * security levels. * default * @param def * @return */ private int determineSecurityLevel(final Definition def) { // use the def security level first if (def.hasSecurityLevel()) { return def.getSecurityLevel(); } // use a configured default security level next if (m_config.hasSecurityLevel()) { return m_config.getSecurityLevel(); } // if no security level configuration exists use int securityLevel = SnmpAgentConfig.NOAUTH_NOPRIV; final String authPassPhrase = (def.getAuthPassphrase() == null ? m_config.getAuthPassphrase() : def.getAuthPassphrase()); final String privPassPhrase = (def.getPrivacyPassphrase() == null ? m_config.getPrivacyPassphrase() : def.getPrivacyPassphrase()); if (authPassPhrase == null) { securityLevel = SnmpAgentConfig.NOAUTH_NOPRIV; } else { if (privPassPhrase == null) { securityLevel = SnmpAgentConfig.AUTH_NOPRIV; } else { securityLevel = SnmpAgentConfig.AUTH_PRIV; } } return securityLevel; } /** * Helper method to search the snmp-config for a port * @param def * @return */ private int determinePort(final Definition def) { return (def.getPort() == 0 ? (m_config.getPort() == 0 ? DEFAULT_SNMP_PORT : m_config.getPort()) : def.getPort()); } /** * Helper method to search the snmp-config * @param def * @return */ private long determineTimeout(final Definition def) { final long timeout = SnmpAgentConfig.DEFAULT_TIMEOUT; return (def.getTimeout() == 0 ? (m_config.getTimeout() == 0 ? timeout : m_config.getTimeout()) : def.getTimeout()); } private int determineRetries(final Definition def) { final int retries = SnmpAgentConfig.DEFAULT_RETRIES; return (def.getRetry() == 0 ? (m_config.getRetry() == 0 ? retries : m_config.getRetry()) : def.getRetry()); } /** * This method determines the configured SNMP version. * the order of operations is: * 1st: return a valid requested version * 2nd: return a valid version defined in a definition within the snmp-config * 3rd: return a valid version in the snmp-config * 4th: return the default version * * @param def * @param requestedSnmpVersion * @return */ private int determineVersion(final Definition def, final int requestedSnmpVersion) { int version = SnmpAgentConfig.VERSION1; String cfgVersion = "v1"; if (requestedSnmpVersion == VERSION_UNSPECIFIED) { if (def.getVersion() == null) { if (m_config.getVersion() == null) { return version; } else { cfgVersion = m_config.getVersion(); } } else { cfgVersion = def.getVersion(); } } else { return requestedSnmpVersion; } if (cfgVersion.equals("v1")) { version = SnmpAgentConfig.VERSION1; } else if (cfgVersion.equals("v2c")) { version = SnmpAgentConfig.VERSION2C; } else if (cfgVersion.equals("v3")) { version = SnmpAgentConfig.VERSION3; } return version; } /** * <p>getSnmpConfig</p> * * @return a {@link org.opennms.netmgt.config.snmp.SnmpConfig} object. */ public static SnmpConfig getSnmpConfig() { SnmpPeerFactory.getReadLock().lock(); try { return m_config; } finally { SnmpPeerFactory.getReadLock().unlock(); } } /** * Enhancement: Allows specific or ranges to be merged into SNMP configuration * with many other attributes. Uses new classes the wrap Castor-generated code to * help with merging, comparing, and optimizing definitions. Thanks for your * initial work on this Gerald. * * Puts a specific IP address with associated read-community string into * the currently loaded snmp-config.xml. * * @param info a {@link org.opennms.netmgt.config.SnmpEventInfo} object. */ public void define(final SnmpEventInfo info) { getWriteLock().lock(); try { final SnmpConfigManager mgr = new SnmpConfigManager(m_config); mgr.mergeIntoConfig(info.createDef()); } finally { getWriteLock().unlock(); } } /** * Creates a string containing the XML of the current SnmpConfig * * @return Marshalled SnmpConfig */ public static String marshallConfig() { SnmpPeerFactory.getReadLock().lock(); try { String marshalledConfig = null; StringWriter writer = null; try { writer = new StringWriter(); JaxbUtils.marshal(m_config, writer); marshalledConfig = writer.toString(); } finally { IOUtils.closeQuietly(writer); } return marshalledConfig; } finally { SnmpPeerFactory.getReadLock().unlock(); } } }