gt:                         DerValue der = new DerValue(pADataValue);
context: /*
   * 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;
  
  import sun.security.krb5.KrbException;
  import sun.security.util.*;
  import sun.security.krb5.Asn1Exception;
  import java.io.IOException;
  import sun.security.krb5.internal.util.KerberosString;
  
  /**
   * Implements the ASN.1 PA-DATA type.
   *
   * <xmp>
   * PA-DATA         ::= SEQUENCE {
   *         -- NOTE: first tag is [1], not [0]
   *         padata-type     [1] Int32,
   *         padata-value    [2] OCTET STRING -- might be encoded AP-REQ
   * }
   * </xmp>
   *
   * <p>
   * This definition reflects the Network Working Group RFC 4120
   * specification available at
   * <a href="http://www.ietf.org/rfc/rfc4120.txt">
   * http://www.ietf.org/rfc/rfc4120.txt</a>.
   */
  
  public class PAData {
      private int pADataType;
      private byte[] pADataValue = null;
      private static final byte TAG_PATYPE = 1;
      private static final byte TAG_PAVALUE = 2;
  
      private PAData() {
      }
  
      public PAData(int new_pADataType, byte[] new_pADataValue) {
          pADataType = new_pADataType;
          if (new_pADataValue != null) {
              pADataValue = new_pADataValue.clone();
          }
      }
  
      public Object clone() {
          PAData new_pAData = new PAData();
          new_pAData.pADataType = pADataType;
          if (pADataValue != null) {
              new_pAData.pADataValue = new byte[pADataValue.length];
              System.arraycopy(pADataValue, 0, new_pAData.pADataValue,
                               0, pADataValue.length);
          }
          return new_pAData;
      }
  
      /**
       * Constructs a PAData object.
       * @param encoding a Der-encoded data.
       * @exception Asn1Exception if an error occurs while decoding an ASN1 encoded data.
       * @exception IOException if an I/O error occurs while reading encoded data.
       */
      public PAData(DerValue encoding) throws Asn1Exception, IOException {
          DerValue der = null;
          if (encoding.getTag() != DerValue.tag_Sequence) {
              throw new Asn1Exception(Krb5.ASN1_BAD_ID);
          }
          der = encoding.getData().getDerValue();
          if ((der.getTag() & 0x1F) == 0x01) {
              this.pADataType = der.getData().getBigInteger().intValue();
          }
          else
              throw new Asn1Exception(Krb5.ASN1_BAD_ID);
          der = encoding.getData().getDerValue();
          if ((der.getTag() & 0x1F) == 0x02) {
              this.pADataValue = der.getData().getOctetString();
          }
          if (encoding.getData().available() > 0)
              throw new Asn1Exception(Krb5.ASN1_BAD_ID);
      }
  
      /**
       * Encodes this object to an OutputStream.
       *
       * @return byte array of the encoded data.
       * @exception IOException if an I/O error occurs while reading encoded data.
       * @exception Asn1Exception on encoding errors.
       */
      public byte[] asn1Encode() throws Asn1Exception, IOException {
  
          DerOutputStream bytes = new DerOutputStream();
          DerOutputStream temp = new DerOutputStream();
  
          temp.putInteger(pADataType);
          bytes.write(DerValue.createTag(DerValue.TAG_CONTEXT, true, TAG_PATYPE), temp);
          temp = new DerOutputStream();
          temp.putOctetString(pADataValue);
          bytes.write(DerValue.createTag(DerValue.TAG_CONTEXT, true, TAG_PAVALUE), temp);
  
          temp = new DerOutputStream();
          temp.write(DerValue.tag_Sequence, bytes);
          return temp.toByteArray();
      }
  
      // accessor methods
      public int getType() {
          return pADataType;
      }
  
      public byte[] getValue() {
          return ((pADataValue == null) ? null : pADataValue.clone());
      }
  
      /**
       * Gets the preferred etype from the PAData array.
       * 1. ETYPE-INFO2-ENTRY with unknown s2kparams ignored
       * 2. ETYPE-INFO2 preferred to ETYPE-INFO
       * 3. multiple entries for same etype in one PA-DATA, use the first one.
       * 4. Multiple PA-DATA with same type, choose the last one
       * (This is useful when PA-DATAs from KRB-ERROR and AS-REP are combined).
       * @return the etype, or defaultEType if not enough info
       * @throws Asn1Exception|IOException if there is an encoding error
       */
      public static int getPreferredEType(PAData[] pas, int defaultEType)
              throws IOException, Asn1Exception {
  
          if (pas == null) return defaultEType;
  
          DerValue d = null, d2 = null;
          for (PAData p: pas) {
              if (p.getValue() == null) continue;
              switch (p.getType()) {
                  case Krb5.PA_ETYPE_INFO:
                      d = new DerValue(p.getValue());
                      break;
                  case Krb5.PA_ETYPE_INFO2:
                      d2 = new DerValue(p.getValue());
                      break;
              }
          }
          if (d2 != null) {
              while (d2.data.available() > 0) {
                  DerValue value = d2.data.getDerValue();
                  ETypeInfo2 tmp = new ETypeInfo2(value);
                  if (tmp.getParams() == null) {
                      // we don't support non-null s2kparams
                      return tmp.getEType();
                  }
              }
          }
          if (d != null) {
              while (d.data.available() > 0) {
                  DerValue value = d.data.getDerValue();
                  ETypeInfo tmp = new ETypeInfo(value);
                  return tmp.getEType();
              }
          }
          return defaultEType;
      }
  
      /**
       * A place to store a pair of salt and s2kparams.
       * An empty salt is changed to null, to be interoperable
       * with Windows 2000 server. This is in fact not correct.
       */
      public static class SaltAndParams {
          public final String salt;
          public final byte[] params;
          public SaltAndParams(String s, byte[] p) {
              if (s != null && s.isEmpty()) s = null;
              this.salt = s;
              this.params = p;
          }
      }
  
      /**
       * Fetches salt and s2kparams value for eType in a series of PA-DATAs.
       * 1. ETYPE-INFO2-ENTRY with unknown s2kparams ignored
       * 2. PA-ETYPE-INFO2 preferred to PA-ETYPE-INFO preferred to PA-PW-SALT.
       * 3. multiple entries for same etype in one PA-DATA, use the first one.
       * 4. Multiple PA-DATA with same type, choose the last one
       * (This is useful when PA-DATAs from KRB-ERROR and AS-REP are combined).
       * @return salt and s2kparams. can be null if not found
       */
      public static SaltAndParams getSaltAndParams(int eType, PAData[] pas)
              throws Asn1Exception, IOException {
  
          if (pas == null) return null;
  
          DerValue d = null, d2 = null;
          String paPwSalt = null;
  
          for (PAData p: pas) {
              if (p.getValue() == null) continue;
              switch (p.getType()) {
                  case Krb5.PA_PW_SALT:
                      paPwSalt = new String(p.getValue(),
                              KerberosString.MSNAME?"UTF8":"8859_1");
                      break;
                  case Krb5.PA_ETYPE_INFO:
                      d = new DerValue(p.getValue());
                      break;
                  case Krb5.PA_ETYPE_INFO2:
                      d2 = new DerValue(p.getValue());
                      break;
              }
          }
          if (d2 != null) {
              while (d2.data.available() > 0) {
                  DerValue value = d2.data.getDerValue();
                  ETypeInfo2 tmp = new ETypeInfo2(value);
                  if (tmp.getParams() == null && tmp.getEType() == eType) {
                      // we don't support non-null s2kparams
                      return new SaltAndParams(tmp.getSalt(), tmp.getParams());
                  }
              }
          }
          if (d != null) {
              while (d.data.available() > 0) {
                  DerValue value = d.data.getDerValue();
                  ETypeInfo tmp = new ETypeInfo(value);
                  if (tmp.getEType() == eType) {
                      return new SaltAndParams(tmp.getSalt(), null);
                  }
              }
          }
          if (paPwSalt != null) {
              return new SaltAndParams(paPwSalt, null);
          }
          return null;
      }
  
      @Override
      public String toString(){
          StringBuilder sb = new StringBuilder();
          sb.append(">>>Pre-Authentication Data:\n\t PA-DATA type = ")
                  .append(pADataType).append('\n');
  
          switch(pADataType) {
              case Krb5.PA_ENC_TIMESTAMP:
                  sb.append("\t PA-ENC-TIMESTAMP");
                  break;
              case Krb5.PA_ETYPE_INFO:
                  if (pADataValue != null) {
                      try {
                          DerValue der = new DerValue(pADataValue);
                          while (der.data.available() > 0) {
                              DerValue value = der.data.getDerValue();
                              ETypeInfo info = new ETypeInfo(value);
                              sb.append("\t PA-ETYPE-INFO etype = ")
                                      .append(info.getEType())
                                      .append(", salt = ")
                                      .append(info.getSalt())
                                      .append('\n');
                          }
                      } catch (IOException|Asn1Exception e) {
                          sb.append("\t <Unparseable PA-ETYPE-INFO>\n");
                      }
                  }
                  break;
              case Krb5.PA_ETYPE_INFO2:
                  if (pADataValue != null) {
                      try {
  