ojluni/src/main/java/sun/security/krb5/internal/ccache/CCacheInputStream.java - platform/libcore.git - Git at Google

 /*
  * 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.  Oracle designates this
  * particular file as subject to the "Classpath" exception as provided
  * by Oracle in the LICENSE file that accompanied this code.
  *
  * 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.
  */

 /*
  *
  *  (C) Copyright IBM Corp. 1999 All Rights Reserved.
  *  Copyright 1997 The Open Group Research Institute.  All rights reserved.
  */

 package sun.security.krb5.internal.ccache;

 import java.io.IOException;
 import java.io.InputStream;
 import java.util.Hashtable;
 import java.util.Vector;
 import java.util.StringTokenizer;
 import sun.security.krb5.*;
 import sun.security.krb5.internal.*;
 import sun.security.krb5.internal.util.KrbDataInputStream;

 /**
  * This class extends KrbDataInputStream. It is used for parsing FCC-format
  * data from file to memory.
  *
  * @author Yanni Zhang
  *
  */
 public class CCacheInputStream extends KrbDataInputStream implements FileCCacheConstants {

     /*
      * FCC version 2 contains type information for principals.  FCC
      * version 1 does not.
      *
      * FCC version 3 contains keyblock encryption type information, and is
      * architecture independent.  Previous versions are not.
      *
      * The code will accept version 1, 2, and 3 ccaches, and depending
      * what KRB5_FCC_DEFAULT_FVNO is set to, it will create version 1, 2,
      * or 3 FCC caches.
      *
      * The default credentials cache should be type 3 for now (see
      * init_ctx.c).
      */
     /* V4 of the credentials cache format allows for header tags */

     private static boolean DEBUG = Krb5.DEBUG;

     public CCacheInputStream(InputStream is){
         super(is);
     }

     /* Read tag field introduced in KRB5_FCC_FVNO_4 */
     // this needs to be public for Kinit.
     public Tag readTag() throws IOException {
         char[] buf = new char[1024];
         byte[] bytes;
         int len;
         int tag = -1;
         int taglen;
         Integer time_offset = null;
         Integer usec_offset = null;

         len = read(2);
         if (len < 0) {
             throw new IOException("stop.");
         }
         bytes = new byte[len + 2];
         if (len > buf.length) {
             throw new IOException("Invalid tag length.");
         }
         while (len > 0) {
             tag    = read(2);
             taglen = read(2);
             switch (tag) {
             case FCC_TAG_DELTATIME:
                 time_offset = new Integer(read(4));
                 usec_offset = new Integer(read(4));
                 break;
             default:
             }
             len = len - (4 + taglen);
         }
         Tag result;
         if (tag == -1) {
         }
         result = new Tag(len, tag, time_offset, usec_offset);
         return result;
     }
     /*
      * In file-based credential cache, the realm name is stored as part of
      * principal name at the first place.
      */
     // made public for KinitOptions to call directly
     public PrincipalName readPrincipal(int version) throws IOException, RealmException {
         int type, length, namelength, kret;
         PrincipalName p;
         String[] pname = null;
         String realm;
         /* Read principal type */
         if (version == KRB5_FCC_FVNO_1) {
             type = KRB5_NT_UNKNOWN;
         } else {
             type = read(4);
         }
         length = read(4);
         String[] result = new String[length + 1];
         /*
          * DCE includes the principal's realm in the count; the new format
          * does not.
          */
         if (version == KRB5_FCC_FVNO_1)
             length--;
         for (int i = 0; i <= length; i++) {
             namelength = read(4);
             if (namelength > MAXNAMELENGTH) {
                 throw new IOException("Invalid name length in principal name.");
             }
             byte[] bytes = new byte[namelength];
             read(bytes, 0, namelength);
             result[i] = new String(bytes);
         }
         if (isRealm(result[0])) {
             realm = result[0];
             pname = new String[length];
             System.arraycopy(result, 1, pname, 0, length);
             p = new PrincipalName(pname, type);
             p.setRealm(realm);
         }
         else p = new PrincipalName(result, type);
         return p;
     }

     /*
      * In practice, a realm is named by uppercasing the DNS domain name. we currently
      * rely on this to determine if the string within the principal identifier is realm
      * name.
      *
      */
     boolean isRealm(String str) {
         try {
             Realm r = new Realm(str);
         }
         catch (Exception e) {
             return false;
         }
         StringTokenizer st = new StringTokenizer(str, ".");
         String s;
         while (st.hasMoreTokens()) {
             s = st.nextToken();
             for (int i = 0; i < s.length(); i++) {
                 if (s.charAt(i) >= 141) {
                     return false;
                 }
             }
         }
         return true;
     }

     EncryptionKey readKey(int version) throws IOException {
         int keyType, keyLen;
         keyType = read(2);
         if (version == KRB5_FCC_FVNO_3)
             read(2); /* keytype recorded twice in fvno 3 */
         keyLen = read(4);
         byte[] bytes = new byte[keyLen];
         for (int i = 0; i < keyLen; i++) {
             bytes[i] = (byte)read();
         }
         return new EncryptionKey(bytes, keyType, new Integer(version));
     }

     long[] readTimes() throws IOException {
         long[] times = new long[4];
         times[0] = (long)read(4) * 1000;
         times[1] = (long)read(4) * 1000;
         times[2] = (long)read(4) * 1000;
         times[3] = (long)read(4) * 1000;
         return times;
     }

     boolean readskey() throws IOException {
         if (read() == 0) {
             return false;
         }
         else return true;
     }

     HostAddress[] readAddr() throws IOException, KrbApErrException {
         int numAddrs, addrType, addrLength;
         numAddrs = read(4);
         if (numAddrs > 0) {
             HostAddress[] addrs = new HostAddress[numAddrs];
             for (int i = 0; i < numAddrs; i++) {
                 addrType = read(2);
                 addrLength = read(4);
                 if (!(addrLength == 4 || addrLength == 16)) {
                     if (DEBUG) {
                         System.out.println("Incorrect address format.");
                     }
                     return null;
                 }
                 byte[] result = new byte[addrLength];
                 for (int j = 0; j < addrLength; j++)
                     result[j] = (byte)read(1);
                 addrs[i] = new HostAddress(addrType, result);
             }
             return addrs;
         }
         return null;
     }

     AuthorizationDataEntry[] readAuth() throws IOException {
         int num, adtype, adlength;
         num = read(4);
         if (num > 0) {
             AuthorizationDataEntry[] auData = new AuthorizationDataEntry[num];
             byte[] data = null;
             for (int i = 0; i < num; i++) {
                 adtype = read(2);
                 adlength = read(4);
                 data = new byte[adlength];
                 for (int j = 0; j < adlength; j++) {
                     data[j] = (byte)read();
                 }
                 auData[i] = new AuthorizationDataEntry(adtype, data);
             }
             return auData;
         }
         else return null;
     }

     byte[] readData() throws IOException {
         int length;
         length = read(4);
         if (length == 0) {
             return null;
         } else {
             byte[] bytes = new byte[length];
             read(bytes, 0, length);
             return bytes;
         }
     }

     boolean[] readFlags() throws IOException {
         boolean[] flags = new boolean[Krb5.TKT_OPTS_MAX+1];
         int ticketFlags;
         ticketFlags = read(4);
         if ((ticketFlags & 0x40000000) == TKT_FLG_FORWARDABLE)
         flags[1] = true;
         if ((ticketFlags & 0x20000000) == TKT_FLG_FORWARDED)
         flags[2] = true;
         if ((ticketFlags & 0x10000000) == TKT_FLG_PROXIABLE)
         flags[3] = true;
         if ((ticketFlags & 0x08000000) == TKT_FLG_PROXY)
         flags[4] = true;
         if ((ticketFlags & 0x04000000) == TKT_FLG_MAY_POSTDATE)
         flags[5] = true;
         if ((ticketFlags & 0x02000000) == TKT_FLG_POSTDATED)
         flags[6] = true;
         if ((ticketFlags & 0x01000000) == TKT_FLG_INVALID)
         flags[7] = true;
         if ((ticketFlags & 0x00800000) == TKT_FLG_RENEWABLE)
         flags[8] = true;
         if ((ticketFlags & 0x00400000) == TKT_FLG_INITIAL)
         flags[9] = true;
         if ((ticketFlags & 0x00200000) == TKT_FLG_PRE_AUTH)
         flags[10] = true;
         if ((ticketFlags & 0x00100000) == TKT_FLG_HW_AUTH)
         flags[11] = true;
         if (DEBUG) {
             String msg = ">>> CCacheInputStream: readFlags() ";
             if (flags[1] == true) {
                 msg += " FORWARDABLE;";
             }
             if (flags[2] == true) {
                 msg += " FORWARDED;";
             }
             if (flags[3] == true) {
                 msg += " PROXIABLE;";
             }
             if (flags[4] == true) {
                 msg += " PROXY;";
             }
             if (flags[5] == true) {
                 msg += " MAY_POSTDATE;";
             }
             if (flags[6] == true) {
                 msg += " POSTDATED;";
             }
             if (flags[7] == true) {
                 msg += " INVALID;";
             }
             if (flags[8] == true) {
                 msg += " RENEWABLE;";
             }

             if (flags[9] == true) {
                 msg += " INITIAL;";
             }
             if (flags[10] == true) {
                 msg += " PRE_AUTH;";
             }
             if (flags[11] == true) {
                 msg += " HW_AUTH;";
             }
             System.out.println(msg);
         }
         return flags;
     }

     /**
      * Reads the next cred in stream.
      * @return the next cred, null if ticket or second_ticket unparseable.
      *
      * Note: MIT krb5 1.8.1 might generate a config entry with server principal
      * X-CACHECONF:/krb5_ccache_conf_data/fast_avail/krbtgt/REALM@REALM. The
      * entry is used by KDC to inform the client that it support certain
      * features. Its ticket is not a valid krb5 ticket and thus this method
      * returns null.
      */
     Credentials readCred(int version) throws IOException,RealmException, KrbApErrException, Asn1Exception {
         PrincipalName cpname = readPrincipal(version);
         if (DEBUG)
             System.out.println(">>>DEBUG <CCacheInputStream>  client principal is " + cpname.toString());
         PrincipalName spname = readPrincipal(version);
         if (DEBUG)
             System.out.println(">>>DEBUG <CCacheInputStream> server principal is " + spname.toString());
         EncryptionKey key = readKey(version);
         if (DEBUG)
             System.out.println(">>>DEBUG <CCacheInputStream> key type: " + key.getEType());
         long times[] = readTimes();
         KerberosTime authtime = new KerberosTime(times[0]);
         KerberosTime starttime =
                 (times[1]==0) ? null : new KerberosTime(times[1]);
         KerberosTime endtime = new KerberosTime(times[2]);
         KerberosTime renewTill =
                 (times[3]==0) ? null : new KerberosTime(times[3]);

         if (DEBUG) {
             System.out.println(">>>DEBUG <CCacheInputStream> auth time: " + authtime.toDate().toString());
             System.out.println(">>>DEBUG <CCacheInputStream> start time: " +
                     ((starttime==null)?"null":starttime.toDate().toString()));
             System.out.println(">>>DEBUG <CCacheInputStream> end time: " + endtime.toDate().toString());
             System.out.println(">>>DEBUG <CCacheInputStream> renew_till time: " +
                     ((renewTill==null)?"null":renewTill.toDate().toString()));
         }
         boolean skey = readskey();
         boolean flags[] = readFlags();
         TicketFlags tFlags = new TicketFlags(flags);
         HostAddress addr[] = readAddr();
         HostAddresses addrs = null;
         if (addr != null) {
             addrs = new HostAddresses(addr);
         }
         AuthorizationDataEntry[] auDataEntry = readAuth();
         AuthorizationData auData = null;
         if (auData != null) {
             auData = new AuthorizationData(auDataEntry);
         }
         byte[] ticketData = readData();
         byte[] ticketData2 = readData();

         try {
             return new Credentials(cpname, spname, key, authtime, starttime,
                 endtime, renewTill, skey, tFlags,
                 addrs, auData,
                 ticketData != null ? new Ticket(ticketData) : null,
                 ticketData2 != null ? new Ticket(ticketData2) : null);
         } catch (Exception e) {     // If any of new Ticket(*) fails.
             return null;
         }
     }
 }
	/*
	* 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. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* 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.
	*/

	/*
	*
	* (C) Copyright IBM Corp. 1999 All Rights Reserved.
	* Copyright 1997 The Open Group Research Institute. All rights reserved.
	*/

	package sun.security.krb5.internal.ccache;

	import java.io.IOException;
	import java.io.InputStream;
	import java.util.Hashtable;
	import java.util.Vector;
	import java.util.StringTokenizer;
	import sun.security.krb5.*;
	import sun.security.krb5.internal.*;
	import sun.security.krb5.internal.util.KrbDataInputStream;

	/**
	* This class extends KrbDataInputStream. It is used for parsing FCC-format
	* data from file to memory.
	*
	* @author Yanni Zhang
	*
	*/
	public class CCacheInputStream extends KrbDataInputStream implements FileCCacheConstants {

	/*
	* FCC version 2 contains type information for principals. FCC
	* version 1 does not.
	*
	* FCC version 3 contains keyblock encryption type information, and is
	* architecture independent. Previous versions are not.
	*
	* The code will accept version 1, 2, and 3 ccaches, and depending
	* what KRB5_FCC_DEFAULT_FVNO is set to, it will create version 1, 2,
	* or 3 FCC caches.
	*
	* The default credentials cache should be type 3 for now (see
	* init_ctx.c).
	*/
	/* V4 of the credentials cache format allows for header tags */

	private static boolean DEBUG = Krb5.DEBUG;

	public CCacheInputStream(InputStream is){
	super(is);
	}

	/* Read tag field introduced in KRB5_FCC_FVNO_4 */
	// this needs to be public for Kinit.
	public Tag readTag() throws IOException {
	char[] buf = new char[1024];
	byte[] bytes;
	int len;
	int tag = -1;
	int taglen;
	Integer time_offset = null;
	Integer usec_offset = null;

	len = read(2);
	if (len < 0) {
	throw new IOException("stop.");
	}
	bytes = new byte[len + 2];
	if (len > buf.length) {
	throw new IOException("Invalid tag length.");
	}
	while (len > 0) {
	tag = read(2);
	taglen = read(2);
	switch (tag) {
	case FCC_TAG_DELTATIME:
	time_offset = new Integer(read(4));
	usec_offset = new Integer(read(4));
	break;
	default:
	}
	len = len - (4 + taglen);
	}
	Tag result;
	if (tag == -1) {
	}
	result = new Tag(len, tag, time_offset, usec_offset);
	return result;
	}
	/*
	* In file-based credential cache, the realm name is stored as part of
	* principal name at the first place.
	*/
	// made public for KinitOptions to call directly
	public PrincipalName readPrincipal(int version) throws IOException, RealmException {
	int type, length, namelength, kret;
	PrincipalName p;
	String[] pname = null;
	String realm;
	/* Read principal type */
	if (version == KRB5_FCC_FVNO_1) {
	type = KRB5_NT_UNKNOWN;
	} else {
	type = read(4);
	}
	length = read(4);
	String[] result = new String[length + 1];
	/*
	* DCE includes the principal's realm in the count; the new format
	* does not.
	*/
	if (version == KRB5_FCC_FVNO_1)
	length--;
	for (int i = 0; i <= length; i++) {
	namelength = read(4);
	if (namelength > MAXNAMELENGTH) {
	throw new IOException("Invalid name length in principal name.");
	}
	byte[] bytes = new byte[namelength];
	read(bytes, 0, namelength);
	result[i] = new String(bytes);
	}
	if (isRealm(result[0])) {
	realm = result[0];
	pname = new String[length];
	System.arraycopy(result, 1, pname, 0, length);
	p = new PrincipalName(pname, type);
	p.setRealm(realm);
	}
	else p = new PrincipalName(result, type);
	return p;
	}

	/*
	* In practice, a realm is named by uppercasing the DNS domain name. we currently
	* rely on this to determine if the string within the principal identifier is realm
	* name.
	*
	*/
	boolean isRealm(String str) {
	try {
	Realm r = new Realm(str);
	}
	catch (Exception e) {
	return false;
	}
	StringTokenizer st = new StringTokenizer(str, ".");
	String s;
	while (st.hasMoreTokens()) {
	s = st.nextToken();
	for (int i = 0; i < s.length(); i++) {
	if (s.charAt(i) >= 141) {
	return false;
	}
	}
	}
	return true;
	}

	EncryptionKey readKey(int version) throws IOException {
	int keyType, keyLen;
	keyType = read(2);
	if (version == KRB5_FCC_FVNO_3)
	read(2); /* keytype recorded twice in fvno 3 */
	keyLen = read(4);
	byte[] bytes = new byte[keyLen];
	for (int i = 0; i < keyLen; i++) {
	bytes[i] = (byte)read();
	}
	return new EncryptionKey(bytes, keyType, new Integer(version));
	}

	long[] readTimes() throws IOException {
	long[] times = new long[4];
	times[0] = (long)read(4) * 1000;
	times[1] = (long)read(4) * 1000;
	times[2] = (long)read(4) * 1000;
	times[3] = (long)read(4) * 1000;
	return times;
	}

	boolean readskey() throws IOException {
	if (read() == 0) {
	return false;
	}
	else return true;
	}

	HostAddress[] readAddr() throws IOException, KrbApErrException {
	int numAddrs, addrType, addrLength;
	numAddrs = read(4);
	if (numAddrs > 0) {
	HostAddress[] addrs = new HostAddress[numAddrs];
	for (int i = 0; i < numAddrs; i++) {
	addrType = read(2);
	addrLength = read(4);
	if (!(addrLength == 4 \|\| addrLength == 16)) {
	if (DEBUG) {
	System.out.println("Incorrect address format.");
	}
	return null;
	}
	byte[] result = new byte[addrLength];
	for (int j = 0; j < addrLength; j++)
	result[j] = (byte)read(1);
	addrs[i] = new HostAddress(addrType, result);
	}
	return addrs;
	}
	return null;
	}

	AuthorizationDataEntry[] readAuth() throws IOException {
	int num, adtype, adlength;
	num = read(4);
	if (num > 0) {
	AuthorizationDataEntry[] auData = new AuthorizationDataEntry[num];
	byte[] data = null;
	for (int i = 0; i < num; i++) {
	adtype = read(2);
	adlength = read(4);
	data = new byte[adlength];
	for (int j = 0; j < adlength; j++) {
	data[j] = (byte)read();
	}
	auData[i] = new AuthorizationDataEntry(adtype, data);
	}
	return auData;
	}
	else return null;
	}

	byte[] readData() throws IOException {
	int length;
	length = read(4);
	if (length == 0) {
	return null;
	} else {
	byte[] bytes = new byte[length];
	read(bytes, 0, length);
	return bytes;
	}
	}

	boolean[] readFlags() throws IOException {
	boolean[] flags = new boolean[Krb5.TKT_OPTS_MAX+1];
	int ticketFlags;
	ticketFlags = read(4);
	if ((ticketFlags & 0x40000000) == TKT_FLG_FORWARDABLE)
	flags[1] = true;
	if ((ticketFlags & 0x20000000) == TKT_FLG_FORWARDED)
	flags[2] = true;
	if ((ticketFlags & 0x10000000) == TKT_FLG_PROXIABLE)
	flags[3] = true;
	if ((ticketFlags & 0x08000000) == TKT_FLG_PROXY)
	flags[4] = true;
	if ((ticketFlags & 0x04000000) == TKT_FLG_MAY_POSTDATE)
	flags[5] = true;
	if ((ticketFlags & 0x02000000) == TKT_FLG_POSTDATED)
	flags[6] = true;
	if ((ticketFlags & 0x01000000) == TKT_FLG_INVALID)
	flags[7] = true;
	if ((ticketFlags & 0x00800000) == TKT_FLG_RENEWABLE)
	flags[8] = true;
	if ((ticketFlags & 0x00400000) == TKT_FLG_INITIAL)
	flags[9] = true;
	if ((ticketFlags & 0x00200000) == TKT_FLG_PRE_AUTH)
	flags[10] = true;
	if ((ticketFlags & 0x00100000) == TKT_FLG_HW_AUTH)
	flags[11] = true;
	if (DEBUG) {
	String msg = ">>> CCacheInputStream: readFlags() ";
	if (flags[1] == true) {
	msg += " FORWARDABLE;";
	}
	if (flags[2] == true) {
	msg += " FORWARDED;";
	}
	if (flags[3] == true) {
	msg += " PROXIABLE;";
	}
	if (flags[4] == true) {
	msg += " PROXY;";
	}
	if (flags[5] == true) {
	msg += " MAY_POSTDATE;";
	}
	if (flags[6] == true) {
	msg += " POSTDATED;";
	}
	if (flags[7] == true) {
	msg += " INVALID;";
	}
	if (flags[8] == true) {
	msg += " RENEWABLE;";
	}

	if (flags[9] == true) {
	msg += " INITIAL;";
	}
	if (flags[10] == true) {
	msg += " PRE_AUTH;";
	}
	if (flags[11] == true) {
	msg += " HW_AUTH;";
	}
	System.out.println(msg);
	}
	return flags;
	}

	/**
	* Reads the next cred in stream.
	* @return the next cred, null if ticket or second_ticket unparseable.
	*
	* Note: MIT krb5 1.8.1 might generate a config entry with server principal
	* X-CACHECONF:/krb5_ccache_conf_data/fast_avail/krbtgt/REALM@REALM. The
	* entry is used by KDC to inform the client that it support certain
	* features. Its ticket is not a valid krb5 ticket and thus this method
	* returns null.
	*/
	Credentials readCred(int version) throws IOException,RealmException, KrbApErrException, Asn1Exception {
	PrincipalName cpname = readPrincipal(version);
	if (DEBUG)
	System.out.println(">>>DEBUG <CCacheInputStream> client principal is " + cpname.toString());
	PrincipalName spname = readPrincipal(version);
	if (DEBUG)
	System.out.println(">>>DEBUG <CCacheInputStream> server principal is " + spname.toString());
	EncryptionKey key = readKey(version);
	if (DEBUG)
	System.out.println(">>>DEBUG <CCacheInputStream> key type: " + key.getEType());
	long times[] = readTimes();
	KerberosTime authtime = new KerberosTime(times[0]);
	KerberosTime starttime =
	(times[1]==0) ? null : new KerberosTime(times[1]);
	KerberosTime endtime = new KerberosTime(times[2]);
	KerberosTime renewTill =
	(times[3]==0) ? null : new KerberosTime(times[3]);

	if (DEBUG) {
	System.out.println(">>>DEBUG <CCacheInputStream> auth time: " + authtime.toDate().toString());
	System.out.println(">>>DEBUG <CCacheInputStream> start time: " +
	((starttime==null)?"null":starttime.toDate().toString()));
	System.out.println(">>>DEBUG <CCacheInputStream> end time: " + endtime.toDate().toString());
	System.out.println(">>>DEBUG <CCacheInputStream> renew_till time: " +
	((renewTill==null)?"null":renewTill.toDate().toString()));
	}
	boolean skey = readskey();
	boolean flags[] = readFlags();
	TicketFlags tFlags = new TicketFlags(flags);
	HostAddress addr[] = readAddr();
	HostAddresses addrs = null;
	if (addr != null) {
	addrs = new HostAddresses(addr);
	}
	AuthorizationDataEntry[] auDataEntry = readAuth();
	AuthorizationData auData = null;
	if (auData != null) {
	auData = new AuthorizationData(auDataEntry);
	}
	byte[] ticketData = readData();
	byte[] ticketData2 = readData();

	try {
	return new Credentials(cpname, spname, key, authtime, starttime,
	endtime, renewTill, skey, tFlags,
	addrs, auData,
	ticketData != null ? new Ticket(ticketData) : null,
	ticketData2 != null ? new Ticket(ticketData2) : null);
	} catch (Exception e) { // If any of new Ticket(*) fails.
	return null;
	}
	}
	}