src/share/classes/com/sun/jndi/dns/ResourceRecord.java

rev 9296 : Detect compression loops in the JNDI DNS client

*** 1,7 ****
  /*
!  * Copyright (c) 2000, 2002, 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.  Oracle designates this
--- 1,7 ----
  /*
!  * Copyright (c) 2000, 2014, 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.  Oracle designates this
*** 82,91 ****
--- 82,96 ----
       */
      static final String rrClassNames[] = {
          null, "IN", null, null, "HS"
      };
  
+     /*
+      * Maximum number of compression references in labels.
+      * Used to detect compression loops.
+      */
+     private static final int MAXIMUM_COMPRESSION_REFERENCES = 16;
  
      byte[] msg;                 // DNS message
      int msgLen;                 // msg size (in octets)
      boolean qSection;           // true if this RR is part of question section
                                  // and therefore has no ttl or rdata
*** 237,247 ****
       */
      private void decode(boolean decodeRdata) throws InvalidNameException {
          int pos = offset;       // index of next unread octet
  
          name = new DnsName();                           // NAME
!         pos = decodeName(pos, name);
  
          rrtype = getUShort(pos);                        // TYPE
          rrtypeName = (rrtype < rrTypeNames.length)
              ? rrTypeNames[rrtype]
              : null;
--- 242,252 ----
       */
      private void decode(boolean decodeRdata) throws InvalidNameException {
          int pos = offset;       // index of next unread octet
  
          name = new DnsName();                           // NAME
!         pos = decodeName(pos, name, 0);
  
          rrtype = getUShort(pos);                        // TYPE
          rrtypeName = (rrtype < rrTypeNames.length)
              ? rrTypeNames[rrtype]
              : null;
*** 316,348 ****
      /*
       * Returns the name encoded at msg[pos], including the root label.
       */
      private DnsName decodeName(int pos) throws InvalidNameException {
          DnsName n = new DnsName();
!         decodeName(pos, n);
          return n;
      }
  
      /*
       * Prepends to "n" the domain name encoded at msg[pos], including the root
       * label.  Returns the index into "msg" following the name.
       */
!     private int decodeName(int pos, DnsName n) throws InvalidNameException {
          if (msg[pos] == 0) {                            // end of name
              n.add(0, "");
              return (pos + 1);
          } else if ((msg[pos] & 0xC0) != 0) {            // name compression
!             decodeName(getUShort(pos) & 0x3FFF, n);
              return (pos + 2);
          } else {                                        // append a label
              int len = msg[pos++];
              try {
                  n.add(0, new String(msg, pos, len, "ISO-8859-1"));
              } catch (java.io.UnsupportedEncodingException e) {
                  // assert false : "ISO-Latin-1 charset unavailable";
              }
!             return decodeName(pos + len, n);
          }
      }
  
      /*
       * Returns the rdata encoded at msg[pos].  The format is dependent
--- 321,357 ----
      /*
       * Returns the name encoded at msg[pos], including the root label.
       */
      private DnsName decodeName(int pos) throws InvalidNameException {
          DnsName n = new DnsName();
!         decodeName(pos, n, 0);
          return n;
      }
  
      /*
       * Prepends to "n" the domain name encoded at msg[pos], including the root
       * label.  Returns the index into "msg" following the name.
       */
!     private int decodeName(int pos, DnsName n, int level)
!         throws InvalidNameException {
!         if (level > MAXIMUM_COMPRESSION_REFERENCES) {
!             throw new InvalidNameException("Too many compression references");
!         }
          if (msg[pos] == 0) {                            // end of name
              n.add(0, "");
              return (pos + 1);
          } else if ((msg[pos] & 0xC0) != 0) {            // name compression
!             decodeName(getUShort(pos) & 0x3FFF, n, level + 1);
              return (pos + 2);
          } else {                                        // append a label
              int len = msg[pos++];
              try {
                  n.add(0, new String(msg, pos, len, "ISO-8859-1"));
              } catch (java.io.UnsupportedEncodingException e) {
                  // assert false : "ISO-Latin-1 charset unavailable";
              }
!             return decodeName(pos + len, n, level);
          }
      }
  
      /*
       * Returns the rdata encoded at msg[pos].  The format is dependent
*** 396,408 ****
      /*
       * Returns the rdata of an SOA record that is encoded at msg[pos].
       */
      private String decodeSoa(int pos) throws InvalidNameException {
          DnsName mname = new DnsName();
!         pos = decodeName(pos, mname);
          DnsName rname = new DnsName();
!         pos = decodeName(pos, rname);
  
          long serial = getUInt(pos);
          pos += 4;
          long refresh = getUInt(pos);
          pos += 4;
--- 405,417 ----
      /*
       * Returns the rdata of an SOA record that is encoded at msg[pos].
       */
      private String decodeSoa(int pos) throws InvalidNameException {
          DnsName mname = new DnsName();
!         pos = decodeName(pos, mname, 0);
          DnsName rname = new DnsName();
!         pos = decodeName(pos, rname, 0);
  
          long serial = getUInt(pos);
          pos += 4;
          long refresh = getUInt(pos);
          pos += 4;