/*
* Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
import com.sun.security.auth.module.Krb5LoginModule;
import java.security.Key;
import java.security.PrivilegedActionException;
import java.security.PrivilegedExceptionAction;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import javax.security.auth.Subject;
import javax.security.auth.kerberos.KerberosKey;
import javax.security.auth.kerberos.KerberosTicket;
import javax.security.auth.login.LoginContext;
import org.ietf.jgss.GSSContext;
import org.ietf.jgss.GSSCredential;
import org.ietf.jgss.GSSException;
import org.ietf.jgss.GSSManager;
import org.ietf.jgss.GSSName;
import org.ietf.jgss.MessageProp;
import org.ietf.jgss.Oid;
import com.sun.security.jgss.ExtendedGSSContext;
import com.sun.security.jgss.InquireType;
import com.sun.security.jgss.AuthorizationDataEntry;
import java.io.File;
/**
* Context of a JGSS subject, encapsulating Subject and GSSContext.
*
* Three "constructors", which acquire the (private) credentials and fill
* it into the Subject:
*
* 1. static fromJAAS(): Creates a Context using a JAAS login config entry
* 2. static fromUserPass(): Creates a Context using a username and a password
* 3. delegated(): A new context which uses the delegated credentials from a
* previously established acceptor Context
*
* Two context initiators, which create the GSSContext object inside:
*
* 1. startAsClient()
* 2. startAsServer()
*
* Privileged action:
* doAs(): Performs an action in the name of the Subject
*
* Handshake process:
* static handShake(initiator, acceptor)
*
* A four-phase typical data communication which includes all four GSS
* actions (wrap, unwrap, getMic and veryfyMiC):
* static transmit(message, from, to)
*/
public class Context {
private Subject s;
private ExtendedGSSContext x;
private boolean f; // context established?
private String name;
private GSSCredential cred; // see static method delegated().
private Context() {}
/**
* Using the delegated credentials from a previous acceptor
* @param c
*/
public Context delegated() throws Exception {
Context out = new Context();
out.s = s;
out.cred = x.getDelegCred();
out.name = name + " as " + out.cred.getName().toString();
return out;
}
/**
* Logins with a JAAS login config entry name
*/
public static Context fromJAAS(final String name) throws Exception {
Context out = new Context();
out.name = name;
LoginContext lc = new LoginContext(name);
lc.login();
out.s = lc.getSubject();
return out;
}
/**
* Logins with a username and a password, using Krb5LoginModule directly
* @param storeKey true if key should be saved, used on acceptor side
*/
public static Context fromUserPass(String user, char[] pass, boolean storeKey)
throws Exception {
Context out = new Context();
out.name = user;
out.s = new Subject();
Krb5LoginModule krb5 = new Krb5LoginModule();
Map<String, String> map = new HashMap<String, String>();
Map<String, Object> shared = new HashMap<String, Object>();
if (pass != null) {
map.put("useFirstPass", "true");
shared.put("javax.security.auth.login.name", user);
shared.put("javax.security.auth.login.password", pass);
} else {
map.put("doNotPrompt", "true");
map.put("useTicketCache", "true");
if (user != null) {
map.put("principal", user);
}
}
if (storeKey) {
map.put("storeKey", "true");
}
krb5.initialize(out.s, null, shared, map);
krb5.login();
krb5.commit();
return out;
}
/**
* Logins with a username and a keytab, using Krb5LoginModule directly
* @param storeKey true if key should be saved, used on acceptor side
*/
public static Context fromUserKtab(String user, String ktab, boolean storeKey)
throws Exception {
Context out = new Context();
out.name = user;
out.s = new Subject();
Krb5LoginModule krb5 = new Krb5LoginModule();
Map<String, String> map = new HashMap<String, String>();
map.put("doNotPrompt", "true");
map.put("useTicketCache", "false");
map.put("useKeyTab", "true");
map.put("keyTab", ktab);
map.put("principal", user);
if (storeKey) {
map.put("storeKey", "true");
}
krb5.initialize(out.s, null, null, map);
krb5.login();
krb5.commit();
return out;
}
/**
* Starts as a client
* @param target communication peer
* @param mech GSS mech
* @throws java.lang.Exception
*/
public void startAsClient(final String target, final Oid mech) throws Exception {
doAs(new Action() {
@Override
public byte[] run(Context me, byte[] dummy) throws Exception {
GSSManager m = GSSManager.getInstance();
me.x = (ExtendedGSSContext)m.createContext(
target.indexOf('@') < 0 ?
m.createName(target, null) :
m.createName(target, GSSName.NT_HOSTBASED_SERVICE),
mech,
cred,
GSSContext.DEFAULT_LIFETIME);
return null;
}
}, null);
f = false;
}
/**
* Starts as a server
* @param mech GSS mech
* @throws java.lang.Exception
*/
public void startAsServer(final Oid mech) throws Exception {
doAs(new Action() {
@Override
public byte[] run(Context me, byte[] dummy) throws Exception {
GSSManager m = GSSManager.getInstance();
me.x = (ExtendedGSSContext)m.createContext(m.createCredential(
null,
GSSCredential.INDEFINITE_LIFETIME,
mech,
GSSCredential.ACCEPT_ONLY));
return null;
}
}, null);
f = false;
}
/**
* Accesses the internal GSSContext object. Currently it's used for --
*
* 1. calling requestXXX() before handshake
* 2. accessing source name
*
* Note: If the application needs to do any privileged call on this
* object, please use doAs(). Otherwise, it can be done directly. The
* methods listed above are all non-privileged calls.
*
* @return the GSSContext object
*/
public ExtendedGSSContext x() {
return x;
}
/**
* Disposes the GSSContext within
* @throws org.ietf.jgss.GSSException
*/
public void dispose() throws GSSException {
x.dispose();
}
/**
* Does something using the Subject inside
* @param action the action
* @param in the input byte
* @return the output byte
* @throws java.lang.Exception
*/
public byte[] doAs(final Action action, final byte[] in) throws Exception {
try {
return Subject.doAs(s, new PrivilegedExceptionAction<byte[]>() {
@Override
public byte[] run() throws Exception {
return action.run(Context.this, in);
}
});
} catch (PrivilegedActionException pae) {
throw pae.getException();
}
}
/**
* Prints status of GSSContext and Subject
* @throws java.lang.Exception
*/
public void status() throws Exception {
System.out.println("STATUS OF " + name.toUpperCase());
try {
StringBuffer sb = new StringBuffer();
if (x.getAnonymityState()) {
sb.append("anon, ");
}
if (x.getConfState()) {
sb.append("conf, ");
}
if (x.getCredDelegState()) {
sb.append("deleg, ");
}
if (x.getIntegState()) {
sb.append("integ, ");
}
if (x.getMutualAuthState()) {
sb.append("mutual, ");
}
if (x.getReplayDetState()) {
sb.append("rep det, ");
}
if (x.getSequenceDetState()) {
sb.append("seq det, ");
}
if (x instanceof ExtendedGSSContext) {
if (((ExtendedGSSContext)x).getDelegPolicyState()) {
sb.append("deleg policy, ");
}
}
System.out.println("Context status of " + name + ": " + sb.toString());
System.out.println(x.getSrcName() + " -> " + x.getTargName());
} catch (Exception e) {
;// Don't care
}
System.out.println("=====================================");
for (Object o : s.getPrivateCredentials()) {
System.out.println(" " + o.getClass());
if (o instanceof KerberosTicket) {
KerberosTicket kt = (KerberosTicket) o;
System.out.println(" " + kt.getServer() + " for " + kt.getClient());
} else if (o instanceof KerberosKey) {
KerberosKey kk = (KerberosKey) o;
System.out.print(" " + kk.getKeyType() + " " + kk.getVersionNumber() + " " + kk.getAlgorithm() + " ");
for (byte b : kk.getEncoded()) {
System.out.printf("%02X", b & 0xff);
}
System.out.println();
} else if (o instanceof Map) {
Map map = (Map) o;
for (Object k : map.keySet()) {
System.out.println(" " + k + ": " + map.get(k));
}
}
}
if (x != null && x instanceof ExtendedGSSContext) {
if (x.isEstablished()) {
ExtendedGSSContext ex = (ExtendedGSSContext)x;
Key k = (Key)ex.inquireSecContext(
InquireType.KRB5_GET_SESSION_KEY);
if (k == null) {
throw new Exception("Session key cannot be null");
}
System.out.println("Session key is: " + k);
boolean[] flags = (boolean[])ex.inquireSecContext(
InquireType.KRB5_GET_TKT_FLAGS);
if (flags == null) {
throw new Exception("Ticket flags cannot be null");
}
System.out.println("Ticket flags is: " + Arrays.toString(flags));
String authTime = (String)ex.inquireSecContext(
InquireType.KRB5_GET_AUTHTIME);
if (authTime == null) {
throw new Exception("Auth time cannot be null");
}
System.out.println("AuthTime is: " + authTime);
if (!x.isInitiator()) {
AuthorizationDataEntry[] ad = (AuthorizationDataEntry[])ex.inquireSecContext(
InquireType.KRB5_GET_AUTHZ_DATA);
System.out.println("AuthzData is: " + Arrays.toString(ad));
}
}
}
}
/**
* Transmits a message from one Context to another. The sender wraps the
* message and sends it to the receiver. The receiver unwraps it, creates
* a MIC of the clear text and sends it back to the sender. The sender
* verifies the MIC against the message sent earlier.
* @param message the message
* @param s1 the sender
* @param s2 the receiver
* @throws java.lang.Exception If anything goes wrong
*/
static public void transmit(final String message, final Context s1,
final Context s2) throws Exception {
final byte[] messageBytes = message.getBytes();
System.out.printf("-------------------- TRANSMIT from %s to %s------------------------\n",
s1.name, s2.name);
byte[] t = s1.doAs(new Action() {
@Override
public byte[] run(Context me, byte[] dummy) throws Exception {
System.out.println("wrap");
MessageProp p1 = new MessageProp(0, true);
byte[] out = me.x.wrap(messageBytes, 0, messageBytes.length, p1);
System.out.println(printProp(p1));
return out;
}
}, null);
t = s2.doAs(new Action() {
@Override
public byte[] run(Context me, byte[] input) throws Exception {
MessageProp p1 = new MessageProp(0, true);
byte[] bytes = me.x.unwrap(input, 0, input.length, p1);
if (!Arrays.equals(messageBytes, bytes))
throw new Exception("wrap/unwrap mismatch");
System.out.println("unwrap");
System.out.println(printProp(p1));
p1 = new MessageProp(0, true);
System.out.println("getMIC");
bytes = me.x.getMIC(bytes, 0, bytes.length, p1);
System.out.println(printProp(p1));
return bytes;
}
}, t);
// Re-unwrap should make p2.isDuplicateToken() returns true
s1.doAs(new Action() {
@Override
public byte[] run(Context me, byte[] input) throws Exception {
MessageProp p1 = new MessageProp(0, true);
System.out.println("verifyMIC");
me.x.verifyMIC(input, 0, input.length,
messageBytes, 0, messageBytes.length,
p1);
System.out.println(printProp(p1));
return null;
}
}, t);
}
/**
* Returns a string description of a MessageProp object
* @param prop the object
* @return the description
*/
static public String printProp(MessageProp prop) {
StringBuffer sb = new StringBuffer();
sb.append("MessagePop: ");
sb.append("QOP="+ prop.getQOP() + ", ");
sb.append(prop.getPrivacy()?"privacy, ":"");
sb.append(prop.isDuplicateToken()?"dup, ":"");
sb.append(prop.isGapToken()?"gap, ":"");
sb.append(prop.isOldToken()?"old, ":"");
sb.append(prop.isUnseqToken()?"unseq, ":"");
sb.append(prop.getMinorString()+ "(" + prop.getMinorStatus()+")");
return sb.toString();
}
/**
* Handshake (security context establishment process) between two Contexts
* @param c the initiator
* @param s the acceptor
* @throws java.lang.Exception
*/
static public void handshake(final Context c, final Context s) throws Exception {
byte[] t = new byte[0];
while (!c.f || !s.f) {
t = c.doAs(new Action() {
@Override
public byte[] run(Context me, byte[] input) throws Exception {
if (me.x.isEstablished()) {
me.f = true;
System.out.println(c.name + " side established");
if (input != null) {
throw new Exception("Context established but " +
"still receive token at " + c.name);
}
return null;
} else {
System.out.println(c.name + " call initSecContext");
return me.x.initSecContext(input, 0, input.length);
}
}
}, t);
t = s.doAs(new Action() {
@Override
public byte[] run(Context me, byte[] input) throws Exception {
if (me.x.isEstablished()) {
me.f = true;
System.out.println(s.name + " side established");
if (input != null) {
throw new Exception("Context established but " +
"still receive token at " + s.name);
}
return null;
} else {
System.out.println(s.name + " called acceptSecContext");
return me.x.acceptSecContext(input, 0, input.length);
}
}
}, t);
}
}
}