Module: Nesser

Defined in:
lib/nesser/logger.rb,
lib/nesser.rb,
lib/nesser/version.rb,
lib/nesser/transaction.rb,
lib/nesser/dns_exception.rb,
lib/nesser/packets/answer.rb,
lib/nesser/packets/packer.rb,
lib/nesser/packets/packet.rb,
lib/nesser/packets/question.rb,
lib/nesser/packets/rr_types.rb,
lib/nesser/packets/unpacker.rb,
lib/nesser/packets/constants.rb

Overview

constants.rb Created June 20, 2017 By Ron Bowes

See: LICENSE.md

A bunch of constants used with DNS - some of them for the protocol, others for error checking the outgoing messages.

Defined Under Namespace

Classes: A, AAAA, Answer, CNAME, DnsException, Logger, MX, NS, Nesser, PTR, Packer, Packet, Question, RRUnknown, SOA, TXT, Transaction, Unpacker

Constant Summary collapse

VERSION = 
"0.0.8"
MAX_RECURSION_DEPTH =

Max recursion depth for parsing names

16
(
  ('a'..'z').to_a +
  ('A'..'Z').to_a +
  ('0'..'9').to_a +
  ['-', '.', '@', '_']
)
MAX_SEGMENT_LENGTH = 
63
MAX_TOTAL_LENGTH = 
253
CLS_IN =

DNS classes - I only define IN (Internet) because I don’t even know what to do with others.

0x0001
CLSES =

Internet

{
  CLS_IN => "IN",
}
QR_QUERY =

Request / response

0x0000
QR_RESPONSE = 
0x0001
QRS = 
{
  QR_QUERY    => "QUERY",
  QR_RESPONSE => "RESPONSE",
}
RCODE_SUCCESS =

Return codes

0x0000
RCODE_FORMAT_ERROR = 
0x0001
RCODE_SERVER_FAILURE =

:servfail

0x0002
RCODE_NAME_ERROR =

:NXDomain

0x0003
RCODE_NOT_IMPLEMENTED = 
0x0004
RCODE_REFUSED = 
0x0005
RCODES = 
{
  RCODE_SUCCESS         => ":NoError (RCODE_SUCCESS)",
  RCODE_FORMAT_ERROR    => ":FormErr (RCODE_FORMAT_ERROR)",
  RCODE_SERVER_FAILURE  => ":ServFail (RCODE_SERVER_FAILURE)",
  RCODE_NAME_ERROR      => ":NXDomain (RCODE_NAME_ERROR)",
  RCODE_NOT_IMPLEMENTED => ":NotImp (RCODE_NOT_IMPLEMENTED)",
  RCODE_REFUSED         => ":Refused (RCODE_REFUSED)",
}
OPCODE_QUERY =

Opcodes - only QUERY is typically used

0x0000
OPCODE_IQUERY = 
0x0800
OPCODE_STATUS = 
0x1000
OPCODES = 
{
  OPCODE_QUERY  => "OPCODE_QUERY",
  OPCODE_IQUERY => "OPCODE_IQUERY",
  OPCODE_STATUS => "OPCODE_STATUS",
}
TYPE_A =

The types that we support

0x0001
TYPE_NS = 
0x0002
TYPE_CNAME = 
0x0005
TYPE_SOA = 
0x0006
TYPE_PTR = 
0x000c
TYPE_MX = 
0x000f
TYPE_TXT = 
0x0010
TYPE_AAAA = 
0x001c
TYPE_ANY = 
0x00FF
TYPES = 
{
  TYPE_A     => "A",
  TYPE_NS    => "NS",
  TYPE_CNAME => "CNAME",
  TYPE_SOA   => "SOA",
  TYPE_PTR   => "PTR",
  TYPE_MX    => "MX",
  TYPE_TXT   => "TXT",
  TYPE_AAAA  => "AAAA",
  TYPE_ANY   => "ANY",
}
FLAG_AA =

The DNS flags

0x0008
FLAG_TC =

Authoritative answer

0x0004
FLAG_RD =

Truncated

0x0002
FLAG_RA =

Recursion desired

0x0001

Class Method Summary collapse

Class Method Details

.FLAGS(flags) ⇒ Object

This converts a set of flags, as an integer, into a string



98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
 
# File 'lib/nesser/packets/constants.rb', line 98

def self.FLAGS(flags)
  result = []
  if((flags & FLAG_AA) == FLAG_AA)
    result << "AA"
  end
  if((flags & FLAG_TC) == FLAG_TC)
    result << "TC"
  end
  if((flags & FLAG_RD) == FLAG_RD)
    result << "RD"
  end
  if((flags & FLAG_RA) == FLAG_RA)
    result << "RA"
  end

  return result.join("|")
end