| /* |
| * Copyright (c) 2009, 2018 Oracle and/or its affiliates. All rights reserved. |
| * |
| * This program and the accompanying materials are made available under the |
| * terms of the Eclipse Public License v. 2.0, which is available at |
| * http://www.eclipse.org/legal/epl-2.0. |
| * |
| * This Source Code may also be made available under the following Secondary |
| * Licenses when the conditions for such availability set forth in the |
| * Eclipse Public License v. 2.0 are satisfied: GNU General Public License, |
| * version 2 with the GNU Classpath Exception, which is available at |
| * https://www.gnu.org/software/classpath/license.html. |
| * |
| * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0 |
| */ |
| |
| package org.jvnet.libpam; |
| |
| import org.jvnet.libpam.impl.PAMLibrary.*; |
| import static org.jvnet.libpam.impl.PAMLibrary.*; |
| import org.jvnet.libpam.impl.PAMLibrary.pam_conv.PamCallback; |
| import org.jvnet.libpam.impl.CLibrary.Passwd; |
| import static org.jvnet.libpam.impl.CLibrary.libc; |
| import com.sun.jna.Pointer; |
| import static com.sun.jna.Native.POINTER_SIZE; |
| import com.sun.jna.ptr.PointerByReference; |
| import java.util.Set; |
| |
| import java.util.logging.Logger; |
| import java.util.logging.Level; |
| |
| /** |
| * PAM authenticator. |
| * |
| * <p> |
| * Instances are thread unsafe and non reentrant. An instace cannot be reused |
| * to authenticate multiple users. |
| * |
| * <p> |
| * For an overview of PAM programming, refer to the following resources: |
| * |
| * <ul> |
| * <li><a href="http://www.netbsd.org/docs/guide/en/chap-pam.html">NetBSD PAM programming guide</a> |
| * <li><a href="http://www.kernel.org/pub/linux/libs/pam/">Linux PAM</a> |
| * </ul> |
| * |
| * @author Kohsuke Kawaguchi |
| */ |
| public class PAM { |
| private pam_handle_t pht; |
| private int ret; |
| |
| /** |
| * Temporarily stored to pass a value from {@link #authenticate(String, String)} |
| * to {@link pam_conv}. |
| */ |
| private String password; |
| |
| /** |
| * Creates a new authenticator. |
| * |
| * @param serviceName |
| * PAM service name. This corresponds to the service name that shows up |
| * in the PAM configuration, |
| */ |
| public PAM(String serviceName) throws PAMException { |
| pam_conv conv = new pam_conv(new PamCallback() { |
| public int callback(int num_msg, Pointer msg, Pointer resp, Pointer pointer) { |
| if(LOGGER.isLoggable(Level.FINE)) |
| LOGGER.fine("pam_conv num_msg="+num_msg); |
| if(password==null) |
| return PAM_CONV_ERR; |
| |
| // allocates pam_response[num_msg]. the caller will free this |
| Pointer m = libc.calloc(pam_response.SIZE,num_msg); |
| resp.setPointer(0,m); |
| |
| for( int i=0; i<num_msg; i++ ) { |
| pam_message pm = new pam_message(msg.getPointer(POINTER_SIZE*i)); |
| if(LOGGER.isLoggable(Level.FINE)) |
| LOGGER.fine(pm.msg_style+":"+pm.msg); |
| if(pm.msg_style==PAM_PROMPT_ECHO_OFF) { |
| pam_response r = new pam_response(m.share(pam_response.SIZE*i)); |
| r.setResp(password); |
| r.write(); // write to (*resp)[i] |
| } |
| } |
| |
| return PAM_SUCCESS; |
| } |
| }); |
| |
| PointerByReference phtr = new PointerByReference(); |
| check(libpam.pam_start(serviceName,null,conv,phtr), "pam_start failed"); |
| pht = new pam_handle_t(phtr.getValue()); |
| } |
| |
| private void check(int ret, String msg) throws PAMException { |
| this.ret = ret; |
| if(ret!=0) { |
| if(pht!=null) |
| throw new PAMException(msg+" : "+libpam.pam_strerror(pht,ret)); |
| else |
| throw new PAMException(msg); |
| } |
| } |
| |
| /** |
| * Authenticate the user with a password. |
| * |
| * @return |
| * Upon a successful authentication, return information about the user. |
| * @throws PAMException |
| * If the authentication fails. |
| */ |
| public UnixUser authenticate(String username, String password) throws PAMException { |
| this.password = password; |
| try { |
| check(libpam.pam_set_item(pht,PAM_USER,username),"pam_set_item failed"); |
| check(libpam.pam_authenticate(pht,0),"pam_authenticate failed"); |
| check(libpam.pam_setcred(pht,0),"pam_setcred failed"); |
| // several different error code seem to be used to represent authentication failures |
| // check(libpam.pam_acct_mgmt(pht,0),"pam_acct_mgmt failed"); |
| |
| PointerByReference r = new PointerByReference(); |
| check(libpam.pam_get_item(pht,PAM_USER,r),"pam_get_item failed"); |
| String userName = r.getValue().getString(0); |
| Passwd pwd = libc.getpwnam(userName); |
| if(pwd==null) |
| throw new PAMException("Authentication succeeded but no user information is available"); |
| return new UnixUser(userName,pwd); |
| } finally { |
| this.password = null; |
| } |
| } |
| |
| /** |
| * Returns the groups a user belongs to |
| * @param username |
| * @return Set of group names |
| * @throws PAMException |
| * @deprecated |
| * Pointless and ugly convenience method. |
| */ |
| public Set<String> getGroupsOfUser(String username) throws PAMException { |
| return new UnixUser(username).getGroups(); |
| } |
| |
| /** |
| * After a successful authentication, call this method to obtain the effective user name. |
| * This can be different from the user name that you passed to the {@link #authenticate(String, String)} |
| * method. |
| */ |
| |
| /** |
| * Performs an early disposal of the object, instead of letting this GC-ed. |
| * Since PAM may hold on to native resources that don't put pressure on Java GC, |
| * doing this is a good idea. |
| * |
| * <p> |
| * This method is called by {@link #finalize()}, too, so it's not required |
| * to call this method explicitly, however. |
| */ |
| public void dispose() { |
| if(pht!=null) { |
| libpam.pam_end(pht,ret); |
| pht=null; |
| } |
| } |
| |
| |
| @Override |
| protected void finalize() throws Throwable { |
| super.finalize(); |
| dispose(); |
| } |
| |
| private static final Logger LOGGER = Logger.getLogger(PAM.class.getName()); |
| } |