summaryrefslogtreecommitdiff
path: root/lib/custodian/protocoltest/dns.rb
blob: 405374727e22ab51b0d98b6db2d417204cf2bacf (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
require 'resolv'

#
#  The DNS-protocol test.
#
#  This object is instantiated if the parser sees a line such as:
#
###
### DNSHOSTS must run dns for bytemark.co.uk resolving NS as '80.68.80.26,85.17.170.78,80.68.80.27'.
###
#
#  The test will fail if the results are not *exactly* as specified.  i.e. If there are too
# many results, or too few, we'll alert.
#
#
module Custodian

  module ProtocolTest

    class DNSTest < TestFactory


      #
      # The line from which we were constructed.
      #
      attr_reader :line

      #
      # Name to resolve, type to resolve, and expected results
      #
      attr_reader :resolve_name, :resolve_type, :resolve_expected



      #
      # Constructor
      #
      def initialize( line )

        #
        #  Save the line
        #
        @line = line

        #
        # Is this test inverted?
        #
        if ( line =~ /must\s+not\s+run\s+/ )
          @inverted = true
        else
          @inverted = false
        end

        if ( line =~ /for\s+([^\s]+)\sresolving\s([A-Z]+)\s+as\s'([^']+)'/ )
          @resolve_name     = $1.dup
          @resolve_type     = $2.dup
          @resolve_expected = $3.dup
        end

        #
        #  Ensure we had all the data.
        #
        raise ArgumentError, "Missing host to resolve" unless( @resolve_name )
        raise ArgumentError, "Missing type of record to lookup" unless( @resolve_type )
        raise ArgumentError, "Missing expected results" unless( @resolve_expected )
        raise ArgumentError, "Uknown record type: #{@resolve_type}" unless( @resolve_type =~ /^(A|NS|MX|AAAA)$/ )

        #
        #  The host to query against
        #
        @host = line.split( /\s+/)[0]

      end




      #
      # Allow this test to be serialized.
      #
      def to_s
        @line
      end




      #
      # Run the test.
      #
      def run_test

        # Reset the result in case we've already run
        @error = nil

        #
        # Do the lookup
        #
        results = resolve_via( @host,  @resolve_type, @resolve_name, 30 )
        return false if ( results.nil? )

        #
        # OK we have an array of results.  If every one of the expected
        # results is contained in those results returned then we're good.
        #
        expected = 0
        if ( results != @resolve_expected )
          @error = "When resolving the name #{@resolve_name} [#{resolve_type}-record lookup] against DNS-server #{@host} we received an error.  The expected result '#{@resolve_expected}' didn't match the returned results '#{results}'"
          return false
        end

        true
      end



      #
      # Resolve an IP
      #
      def resolve_via( server, ltype, name, period )

        results = Array.new()

        begin
          timeout( period ) do

            begin
              Resolv::DNS.open(:nameserver=>[server]) do |dns|
                case ltype

                when /^A$/ then
                  dns.getresources(name, Resolv::DNS::Resource::IN::A).map{ |r| results.push(r.address.to_s()) }

                when /^AAAA$/ then
      dns.getresources(name, Resolv::DNS::Resource::IN::AAAA).map{ |r| results.push( r.address.to_s())  }

                when /^NS$/ then
                  dns.getresources(name, Resolv::DNS::Resource::IN::NS).map{ |r| results.push( Resolv.getaddresses(r.name.to_s())) }

                when /^MX$/ then
                  dns.getresources(name, Resolv::DNS::Resource::IN::MX).map{ |r| results.push( Resolv.getaddresses(r.exchange.to_s())) }
                else
                  @error = "Unknown record type to resolve: '#{ltype}'"
                  return nil
                end
              end
            rescue Exception => x
              @error = "Exception was received when resolving : #{x}"
              return nil
            end
          end
        rescue Timeout::Error => e
          @error = "Timed-out performing DNS lookups #{e}"
          return nil
        end

        #
        #  Flatten via a hash.
        #
        h = Hash.new()
        results.sort.each do |key|
          if ( key.kind_of? Array )
            key.each do |n|
              h[n]=1
            end
          else
            h[key]=1
          end
        end
        h.keys.sort!.join( "," )
      end



      #
      # If the test fails then report the error.
      #
      def error
        @error
      end




      register_test_type "dns"




    end
  end
end