java.lang.Object
org.minidns.record.Data
org.minidns.record.NSEC
public class NSECextends Data
DNS NSEC (Next Secure) record payload for DNSSEC.
Provides authenticated denial of existence for DNS records and links to the next valid name in the zone.

  • Field Details

    • LOGGER

      private static final Logger LOGGER
      Logger for this class.

    • next

      public final DnsName next
      The next owner name that contains a authoritative data or a delegation point.

    • typeBitmap

      private final byte[] typeBitmap
      the type bitmap

    • types

      public final List<Record.TYPE> types
      The RR types existing at the owner name.

  • Constructor Details

    • NSEC

      public NSEC(String next, List<Record.TYPE> types)
      Builds a record from a textual next owner name and its type list.
      Parameters:
      next - the next owner name, as a textual DNS name
      types - the RR types present at the owner name

    • NSEC

      public NSEC(String next, Record.TYPE... types)
      Builds a record from a textual next owner name and its types.
      Parameters:
      next - the next owner name, as a textual DNS name
      types - the RR types present at the owner name

    • NSEC

      public NSEC(DnsName next, List<Record.TYPE> types)
      Builds a record from a next owner name and its type list.
      Parameters:
      next - the next owner name
      types - the RR types present at the owner name

  • Method Details

    • parse

      public static NSEC parse(DataInputStream dis, byte[] data, int length) throws IOException
      Reads a record from the wire, deriving the type bitmap length from the payload.
      Parameters:
      dis - the stream positioned at the start of the record payload
      data - the buffer backing the whole record, used to parse the next owner name
      length - the payload length in bytes
      Returns:
      the parsed record
      Throws:
      IOException - if length is shorter than the next owner name, or if the type bitmap is truncated

    • getType

      public Record.TYPE getType()
      Reports the NSEC record type.
      Specified by:
      getType in class Data
      Returns:
      The DNS record type of this payload.

    • serialize

      public void serialize(DataOutputStream dos) throws IOException
      Writes the next owner name and type bitmap to the stream.
      Specified by:
      serialize in class Data
      Parameters:
      dos - the output stream to serialize to.
      Throws:
      IOException - if an I/O error occurs.

    • toString

      public String toString()
      Renders the next owner name followed by its type list.
      Overrides:
      toString in class Object

    • createTypeBitMap

      static byte[] createTypeBitMap(List<Record.TYPE> types)
      Create type bitmap
      Parameters:
      types - the RR types to encode, sorted into window blocks internally
      Returns:
      the bitmap in RFC 4034 window block form

    • writeOutBlock

      private static void writeOutBlock(byte[] values, DataOutputStream dos) throws IOException
      Writes the block, stopping after its last non-zero byte.
      Parameters:
      values - the block's bytes
      dos - where to write
      Throws:
      IOException - if the write fails

    • readTypeBitMap

      static List<Record.TYPE> readTypeBitMap(byte[] typeBitmap) throws IOException
      Read type bitmap
      Parameters:
      typeBitmap - the bitmap in RFC 4034 window block form
      Returns:
      the RR types it sets, with unknown types logged and skipped
      Throws:
      IOException - if the window blocks end before their declared bitmap bytes