/**
* 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. See accompanying LICENSE file.
*/
package com.hortonworks.registries.auth.server;
import com.hortonworks.registries.auth.client.AuthenticatedURL;
import com.hortonworks.registries.auth.client.AuthenticationException;
import com.hortonworks.registries.auth.client.KerberosAuthenticator;
import com.hortonworks.registries.auth.util.*;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.security.Principal;
import java.text.SimpleDateFormat;
import java.util.*;
/**
* <p>The {@link AuthenticationFilter} enables protecting web application
* resources with different (pluggable)
* authentication mechanisms and signer secret providers.
* </p>
* <p>
* Out of the box it provides 2 authentication mechanisms: Pseudo and Kerberos SPNEGO.
* </p>
* Additional authentication mechanisms are supported via the {@link AuthenticationHandler} interface.
* <p>
* This filter delegates to the configured authentication handler for authentication and once it obtains an
* {@link AuthenticationToken} from it, sets a signed HTTP cookie with the token. For client requests
* that provide the signed HTTP cookie, it verifies the validity of the cookie, extracts the user information
* and lets the request proceed to the target resource.
* </p>
* The supported configuration properties are:
* <ul>
* <li>config.prefix: indicates the prefix to be used by all other configuration properties, the default value
* is no prefix. See below for details on how/why this prefix is used.</li>
* <li>[#PREFIX#.]type: simple|kerberos|#CLASS#, 'simple' is short for the
* {@link PseudoAuthenticationHandler}, 'kerberos' is short for {@link KerberosAuthenticationHandler}, otherwise
* the full class name of the {@link AuthenticationHandler} must be specified.</li>
* <li>[#PREFIX#.]signature.secret.file: when signer.secret.provider is set to
* "file" or not specified, this is the location of file including the secret
* used to sign the HTTP cookie.</li>
* <li>[#PREFIX#.]token.validity: time -in seconds- that the generated token is
* valid before a new authentication is triggered, default value is
* <code>3600</code> seconds. This is also used for the rollover interval for
* the "random" SignerSecretProvider.</li>
* <li>[#PREFIX#.]cookie.domain: domain to use for the HTTP cookie that stores the authentication token.</li>
* <li>[#PREFIX#.]cookie.path: path to use for the HTTP cookie that stores the authentication token.</li>
* </ul>
* <p>
* The rest of the configuration properties are specific to the {@link AuthenticationHandler} implementation and the
* {@link AuthenticationFilter} will take all the properties that start with the prefix #PREFIX#, it will remove
* the prefix from it and it will pass them to the the authentication handler for initialization. Properties that do
* not start with the prefix will not be passed to the authentication handler initialization.
* </p>
* <p>
* Out of the box it provides 2 signer secret provider implementations:
* "file" and "random"
* </p>
* Additional signer secret providers are supported via the
* {@link SignerSecretProvider} class.
* <p>
* For the HTTP cookies mentioned above, the SignerSecretProvider is used to
* determine the secret to use for signing the cookies. Different
* implementations can have different behaviors. The "file" implementation
* loads the secret from a specified file. The "random" implementation uses a
* randomly generated secret that rolls over at the interval specified by the
* [#PREFIX#.]token.validity mentioned above.
* </p>
* The relevant configuration properties are:
* <ul>
* <li>signer.secret.provider: indicates the name of the SignerSecretProvider
* class to use. Possible values are: "file", "random", or a
* classname. If not specified, the "file" implementation will be used with
* [#PREFIX#.]signature.secret.file; and if that's not specified, the "random"
* implementation will be used.</li>
* <li>[#PREFIX#.]signature.secret.file: When the "file" implementation is
* specified, this content of this file is used as the secret.</li>
* <li>[#PREFIX#.]token.validity: When the "random"
* implementation is specified, this value is used as the rollover
* interval.</li>
* </ul>
* For subclasses of AuthenticationFilter that want additional control over the
* SignerSecretProvider, they can use the following attribute set in the
* ServletContext:
* <ul>
* <li>signer.secret.provider.object: A SignerSecretProvider implementation can
* be passed here that will be used instead of the signer.secret.provider
* configuration property. Note that the class should already be
* initialized.</li>
* </ul>
*/
public class AuthenticationFilter implements Filter {
private static Logger LOG = LoggerFactory.getLogger(AuthenticationFilter.class);
/**
* Constant for the property that specifies the configuration prefix.
*/
public static final String CONFIG_PREFIX = "config.prefix";
/**
* Constant for the property that specifies the authentication handler to use.
*/
public static final String AUTH_TYPE = "type";
/**
* Constant for the property that specifies the secret to use for signing the HTTP Cookies.
*/
public static final String SIGNATURE_SECRET = "signature.secret";
public static final String SIGNATURE_SECRET_FILE = SIGNATURE_SECRET + ".file";
/**
* Constant for the configuration property that indicates the validity of the generated token.
*/
public static final String AUTH_TOKEN_VALIDITY = "token.validity";
/**
* Constant for the configuration property that indicates the domain to use in the HTTP cookie.
*/
public static final String COOKIE_DOMAIN = "cookie.domain";
/**
* Constant for the configuration property that indicates the path to use in the HTTP cookie.
*/
public static final String COOKIE_PATH = "cookie.path";
/**
* Constant for the configuration property that indicates the name of the
* SignerSecretProvider class to use.
* Possible values are: "file", "random" or a classname.
* If not specified, the "file" implementation will be used with
* SIGNATURE_SECRET_FILE; and if that's not specified, the "random"
* implementation will be used.
*/
public static final String SIGNER_SECRET_PROVIDER =
"signer.secret.provider";
/**
* Constant for the ServletContext attribute that can be used for providing a
* custom implementation of the SignerSecretProvider. Note that the class
* should already be initialized. If not specified, SIGNER_SECRET_PROVIDER
* will be used.
*/
public static final String SIGNER_SECRET_PROVIDER_ATTRIBUTE =
"signer.secret.provider.object";
private Properties config;
private Signer signer;
private SignerSecretProvider secretProvider;
private AuthenticationHandler authHandler;
private long validity;
private String cookieDomain;
private String cookiePath;
private boolean isInitializedByTomcat;
/**
* <p>Initializes the authentication filter and signer secret provider.</p>
* It instantiates and initializes the specified {@link
* AuthenticationHandler}.
*
* @param filterConfig filter configuration.
*
* @throws ServletException thrown if the filter or the authentication handler could not be initialized properly.
*/
@Override
public void init(FilterConfig filterConfig) throws ServletException {
String configPrefix = filterConfig.getInitParameter(CONFIG_PREFIX);
configPrefix = (configPrefix != null) ? configPrefix + "." : "";
config = getConfiguration(configPrefix, filterConfig);
String authHandlerName = config.getProperty(AUTH_TYPE, null);
String authHandlerClassName;
if (authHandlerName == null) {
throw new ServletException("Authentication type must be specified: " +
PseudoAuthenticationHandler.TYPE + "|" +
KerberosAuthenticationHandler.TYPE + "|<class>");
}
if (authHandlerName.toLowerCase(Locale.ENGLISH).equals(
PseudoAuthenticationHandler.TYPE)) {
authHandlerClassName = PseudoAuthenticationHandler.class.getName();
} else if (authHandlerName.toLowerCase(Locale.ENGLISH).equals(
KerberosAuthenticationHandler.TYPE)) {
authHandlerClassName = KerberosAuthenticationHandler.class.getName();
} else {
authHandlerClassName = authHandlerName;
}
validity = Long.parseLong(config.getProperty(AUTH_TOKEN_VALIDITY, "36000"))
* 1000; //10 hours
initializeSecretProvider(filterConfig);
initializeAuthHandler(authHandlerClassName, filterConfig);
cookieDomain = config.getProperty(COOKIE_DOMAIN, null);
cookiePath = config.getProperty(COOKIE_PATH, null);
}
protected void initializeAuthHandler(String authHandlerClassName, FilterConfig filterConfig)
throws ServletException {
try {
Class<?> klass = Thread.currentThread().getContextClassLoader().loadClass(authHandlerClassName);
authHandler = (AuthenticationHandler) klass.newInstance();
authHandler.init(config);
} catch (ClassNotFoundException | InstantiationException |
IllegalAccessException ex) {
throw new ServletException(ex);
}
}
protected void initializeSecretProvider(FilterConfig filterConfig)
throws ServletException {
secretProvider = (SignerSecretProvider) filterConfig.getServletContext().
getAttribute(SIGNER_SECRET_PROVIDER_ATTRIBUTE);
if (secretProvider == null) {
// As tomcat cannot specify the provider object in the configuration.
// It'll go into this path
try {
secretProvider = constructSecretProvider(
filterConfig.getServletContext(),
config, false);
isInitializedByTomcat = true;
} catch (Exception ex) {
throw new ServletException(ex);
}
}
signer = new Signer(secretProvider);
}
public static SignerSecretProvider constructSecretProvider(
ServletContext ctx, Properties config,
boolean disallowFallbackToRandomSecretProvider) throws Exception {
String name = config.getProperty(SIGNER_SECRET_PROVIDER, "file");
long validity = Long.parseLong(config.getProperty(AUTH_TOKEN_VALIDITY,
"36000")) * 1000;
if (!disallowFallbackToRandomSecretProvider
&& "file".equals(name)
&& config.getProperty(SIGNATURE_SECRET_FILE) == null) {
name = "random";
}
SignerSecretProvider provider;
if ("file".equals(name)) {
provider = new FileSignerSecretProvider();
try {
provider.init(config, ctx, validity);
} catch (Exception e) {
if (!disallowFallbackToRandomSecretProvider) {
LOG.info("Unable to initialize FileSignerSecretProvider, " +
"falling back to use random secrets.");
provider = new RandomSignerSecretProvider();
provider.init(config, ctx, validity);
} else {
throw e;
}
}
} else if ("random".equals(name)) {
provider = new RandomSignerSecretProvider();
provider.init(config, ctx, validity);
} else {
provider = (SignerSecretProvider) Thread.currentThread().
getContextClassLoader().loadClass(name).newInstance();
provider.init(config, ctx, validity);
}
return provider;
}
/**
* Returns the configuration properties of the {@link AuthenticationFilter}
* without the prefix. The returned properties are the same that the
* {@link #getConfiguration(String, FilterConfig)} method returned.
*
* @return the configuration properties.
*/
protected Properties getConfiguration() {
return config;
}
/**
* Returns the authentication handler being used.
*
* @return the authentication handler being used.
*/
protected AuthenticationHandler getAuthenticationHandler() {
return authHandler;
}
/**
* Returns if a random secret is being used.
*
* @return if a random secret is being used.
*/
protected boolean isRandomSecret() {
return secretProvider.getClass() == RandomSignerSecretProvider.class;
}
/**
* Returns if a custom implementation of a SignerSecretProvider is being used.
*
* @return if a custom implementation of a SignerSecretProvider is being used.
*/
protected boolean isCustomSignerSecretProvider() {
Class<?> clazz = secretProvider.getClass();
return clazz != FileSignerSecretProvider.class && clazz !=
RandomSignerSecretProvider.class;
}
/**
* Returns the validity time of the generated tokens.
*
* @return the validity time of the generated tokens, in seconds.
*/
protected long getValidity() {
return validity / 1000;
}
/**
* Returns the cookie domain to use for the HTTP cookie.
*
* @return the cookie domain to use for the HTTP cookie.
*/
protected String getCookieDomain() {
return cookieDomain;
}
/**
* Returns the cookie path to use for the HTTP cookie.
*
* @return the cookie path to use for the HTTP cookie.
*/
protected String getCookiePath() {
return cookiePath;
}
/**
* Destroys the filter.
* <p>
* It invokes the {@link AuthenticationHandler#destroy()} method to release any resources it may hold.
*/
@Override
public void destroy() {
if (authHandler != null) {
authHandler.destroy();
authHandler = null;
}
if (secretProvider != null && isInitializedByTomcat) {
secretProvider.destroy();
secretProvider = null;
}
}
/**
* Returns the filtered configuration (only properties starting with the specified prefix). The property keys
* are also trimmed from the prefix. The returned {@link Properties} object is used to initialized the
* {@link AuthenticationHandler}.
* <p>
* This method can be overriden by subclasses to obtain the configuration from other configuration source than
* the web.xml file.
*
* @param configPrefix configuration prefix to use for extracting configuration properties.
* @param filterConfig filter configuration object
*
* @return the configuration to be used with the {@link AuthenticationHandler} instance.
*
* @throws ServletException thrown if the configuration could not be created.
*/
protected Properties getConfiguration(String configPrefix, FilterConfig filterConfig) throws ServletException {
Properties props = new Properties();
Enumeration<?> names = filterConfig.getInitParameterNames();
while (names.hasMoreElements()) {
String name = (String) names.nextElement();
if (name.startsWith(configPrefix)) {
String value = filterConfig.getInitParameter(name);
props.put(name.substring(configPrefix.length()), value);
}
}
return props;
}
/**
* Returns the full URL of the request including the query string.
* <p>
* Used as a convenience method for logging purposes.
*
* @param request the request object.
*
* @return the full URL of the request including the query string.
*/
protected String getRequestURL(HttpServletRequest request) {
StringBuffer sb = request.getRequestURL();
if (request.getQueryString() != null) {
sb.append("?").append(request.getQueryString());
}
return sb.toString();
}
/**
* Returns the {@link AuthenticationToken} for the request.
* <p>
* It looks at the received HTTP cookies and extracts the value of the {@link AuthenticatedURL#AUTH_COOKIE}
* if present. It verifies the signature and if correct it creates the {@link AuthenticationToken} and returns
* it.
* <p>
* If this method returns <code>null</code> the filter will invoke the configured {@link AuthenticationHandler}
* to perform user authentication.
*
* @param request request object.
*
* @return the Authentication token if the request is authenticated, <code>null</code> otherwise.
*
* @throws IOException thrown if an IO error occurred.
* @throws AuthenticationException thrown if the token is invalid or if it has expired.
*/
protected AuthenticationToken getToken(HttpServletRequest request) throws IOException, AuthenticationException {
AuthenticationToken token = null;
String tokenStr = null;
Cookie[] cookies = request.getCookies();
if (cookies != null) {
for (Cookie cookie : cookies) {
if (cookie.getName().equals(AuthenticatedURL.AUTH_COOKIE)) {
tokenStr = cookie.getValue();
try {
tokenStr = signer.verifyAndExtract(tokenStr);
} catch (SignerException ex) {
throw new AuthenticationException(ex);
}
break;
}
}
}
if (tokenStr != null) {
token = AuthenticationToken.parse(tokenStr);
if (!token.getType().equals(authHandler.getType())) {
throw new AuthenticationException("Invalid AuthenticationToken type");
}
if (token.isExpired()) {
throw new AuthenticationException("AuthenticationToken expired");
}
}
return token;
}
/**
* If the request has a valid authentication token it allows the request to continue to the target resource,
* otherwise it triggers an authentication sequence using the configured {@link AuthenticationHandler}.
*
* @param request the request object.
* @param response the response object.
* @param filterChain the filter chain object.
*
* @throws IOException thrown if an IO error occurred.
* @throws ServletException thrown if a processing error occurred.
*/
@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain filterChain)
throws IOException, ServletException {
boolean unauthorizedResponse = true;
int errCode = HttpServletResponse.SC_UNAUTHORIZED;
AuthenticationException authenticationEx = null;
HttpServletRequest httpRequest = (HttpServletRequest) request;
HttpServletResponse httpResponse = (HttpServletResponse) response;
boolean isHttps = "https".equals(httpRequest.getScheme());
try {
boolean newToken = false;
AuthenticationToken token;
try {
token = getToken(httpRequest);
} catch (AuthenticationException ex) {
LOG.warn("AuthenticationToken ignored: " + ex.getMessage());
// will be sent back in a 401 unless filter authenticates
authenticationEx = ex;
token = null;
}
if (authHandler.managementOperation(token, httpRequest, httpResponse)) {
if (token == null) {
if (LOG.isDebugEnabled()) {
LOG.debug("Request [{}] triggering authentication", getRequestURL(httpRequest));
}
token = authHandler.authenticate(httpRequest, httpResponse);
if (token != null && token.getExpires() != 0 &&
token != AuthenticationToken.ANONYMOUS) {
token.setExpires(System.currentTimeMillis() + getValidity() * 1000);
}
newToken = true;
}
if (token != null) {
unauthorizedResponse = false;
if (LOG.isDebugEnabled()) {
LOG.debug("Request [{}] user [{}] authenticated", getRequestURL(httpRequest), token.getUserName());
}
final AuthenticationToken authToken = token;
httpRequest = new HttpServletRequestWrapper(httpRequest) {
@Override
public String getAuthType() {
return authToken.getType();
}
@Override
public String getRemoteUser() {
return authToken.getUserName();
}
@Override
public Principal getUserPrincipal() {
return (authToken != AuthenticationToken.ANONYMOUS) ? authToken : null;
}
};
if (newToken && !token.isExpired() && token != AuthenticationToken.ANONYMOUS) {
String signedToken = signer.sign(token.toString());
createAuthCookie(httpResponse, signedToken, getCookieDomain(),
getCookiePath(), token.getExpires(), isHttps);
}
doFilter(filterChain, httpRequest, httpResponse);
}
} else {
unauthorizedResponse = false;
}
} catch (AuthenticationException ex) {
// exception from the filter itself is fatal
errCode = HttpServletResponse.SC_FORBIDDEN;
authenticationEx = ex;
if (LOG.isDebugEnabled()) {
LOG.debug("Authentication exception: " + ex.getMessage(), ex);
} else {
LOG.warn("Authentication exception: " + ex.getMessage());
}
}
if (unauthorizedResponse) {
if (!httpResponse.isCommitted()) {
createAuthCookie(httpResponse, "", getCookieDomain(),
getCookiePath(), 0, isHttps);
// If response code is 401. Then WWW-Authenticate Header should be
// present.. reset to 403 if not found..
if ((errCode == HttpServletResponse.SC_UNAUTHORIZED)
&& (!httpResponse.containsHeader(
KerberosAuthenticator.WWW_AUTHENTICATE))) {
errCode = HttpServletResponse.SC_FORBIDDEN;
}
if (authenticationEx == null) {
httpResponse.sendError(errCode, "Authentication required");
} else {
httpResponse.sendError(errCode, authenticationEx.getMessage());
}
}
}
}
/**
* Delegates call to the servlet filter chain. Sub-classes my override this
* method to perform pre and post tasks.
*/
protected void doFilter(FilterChain filterChain, HttpServletRequest request,
HttpServletResponse response) throws IOException, ServletException {
filterChain.doFilter(request, response);
}
/**
* Creates the authentication HTTP cookie.
*
* @param token authentication token for the cookie.
* @param expires UNIX timestamp that indicates the expire date of the
* cookie. It has no effect if its value < 0.
*
*/
public static void createAuthCookie(HttpServletResponse resp, String token,
String domain, String path, long expires,
boolean isSecure) {
StringBuilder sb = new StringBuilder(AuthenticatedURL.AUTH_COOKIE)
.append("=");
if (token != null && token.length() > 0) {
sb.append("\"").append(token).append("\"");
}
if (path != null) {
sb.append("; Path=").append(path);
}
if (domain != null) {
sb.append("; Domain=").append(domain);
}
if (expires >= 0) {
Date date = new Date(expires);
SimpleDateFormat df = new SimpleDateFormat("EEE, " +
"dd-MMM-yyyy HH:mm:ss zzz");
df.setTimeZone(TimeZone.getTimeZone("GMT"));
sb.append("; Expires=").append(df.format(date));
}
if (isSecure) {
sb.append("; Secure");
}
sb.append("; HttpOnly");
resp.addHeader("Set-Cookie", sb.toString());
}
}