summaryrefslogtreecommitdiff
path: root/lib/custodian/protocoltest/tcp.rb
blob: 3fd4129e4db16da478f48ccf8fad8f87bb1ef3f1 (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
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
require 'custodian/settings'
require 'custodian/testfactory'
require 'socket'
require 'timeout'


#
#  The TCP-protocol test.
#
#  This object is instantiated if the parser sees a line such as:
#
###
### foo.vm.bytemark.co.uk must run tcp on 22 with banner 'ssh' otherwise 'ssh fail'.
###
#
#  The specification of the port is mandatory, the banner is optional.
#
module Custodian

  module ProtocolTest

    class TCPTest < TestFactory


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


      #
      # The host to test against.
      #
      attr_reader :host


      #
      # The port to connect to.
      #
      attr_reader :port


      #
      # Is this test inverted?
      #
      attr_reader :inverted


      #
      #  The banner to look for, may be nil.
      #
      attr_reader :banner




      #
      # Constructor
      #
      # Ensure we received a port to run the TCP-test against.
      #
      def initialize( line )

        #
        # Save the line
        #
        @line = line

        #
        # Save the host
        #
        @host  = line.split( /\s+/)[0]

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

        #
        # Save the port
        #
        if ( line =~ /on\s+([0-9]+)/ )
          @port = $1.dup
        else
          @port = nil
        end

        #
        # Save the optional banner.
        #
        if ( line =~ /with\s+banner\s+'([^']+)'/ )
          @banner = $1.dup
        else
          @banner = nil
        end

        @error = nil

        if ( @port.nil? )
          raise ArgumentError, "Missing port to test against"
        end
      end




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



      #
      # Run the test.
      #
      def run_test

        # reset the error, in case we were previously executed.
        @error = nil

        return( run_test_internal( @host, @port, @banner, ( ! @banner.nil? ) ) )
      end



      #
      # Run the connection test - optionally matching against the banner.
      #
      # If the banner is nil then we're merely testing we can connect and
      # send the string "quit".
      #
      # There are two ways this method will be invoked, via the configuration file:
      #
      #         foo.vm.bytemark.co.uk must run tcp on 24 with banner 'smtp'
      # or
      #         1.2.3.44 must run tcp on 53 otherwise 'named failed'.
      #
      # Here we're going to try to resolve the hostname in the first version
      # into both IPv6 and IPv4 addresses and test them both.
      #
      # A failure in either version will result in a failure.
      #
      def run_test_internal( host, port, banner = nil, do_read = false )

        #
        # Get the timeout period.
        #
        settings = Custodian::Settings.instance()
        period   = settings.timeout()

        #
        # Perform the DNS lookups of the specified name.
        #
        ips = Array.new()

        #
        #  Does the name look like an IP?
        #
        begin
          x = IPAddr.new( host )
          if ( x.ipv4? or x.ipv6? )
            ips.push( host )
          end
        rescue ArgumentError
          #
          # NOP - Just means the host wasn't an IP
          #
        end

        #
        #  Both types?
        #
        do_ipv6 = true
        do_ipv4 = true

        #
        # Allow the test to disable one/both
        #
        if ( @line =~ /ipv4_only/ )
          do_ipv6 = false
        end
        if ( @line =~ /ipv6_only/ )
          do_ipv4 = false
        end


        #
        # OK if it didn't look like an IP address then attempt to
        # look it up, as both IPv4 and IPv6.
        #
        begin
          timeout( period ) do

            Resolv::DNS.open do |dns|

              if ( do_ipv4 )
                ress = dns.getresources(host, Resolv::DNS::Resource::IN::A)
                ress.map { |r| ips.push( r.address.to_s ) }
              end
              if ( do_ipv6 )
                ress = dns.getresources(host, Resolv::DNS::Resource::IN::AAAA)
                ress.map { |r| ips.push( r.address.to_s ) }
              end
            end
          end
        rescue Timeout::Error => e
          @error = "Timed-out performing DNS lookups: #{e}"
          return nil
        end


        #
        #  Did we fail to perform a DNS lookup?
        #
        if ( ips.empty? )
          @error = "#{@host} failed to resolve to either IPv4 or IPv6"
          return false
        end


        #
        # Run the test, avoiding the use of the shell, for each of the
        # IPv4 and IPv6 addresses we discovered, or the host that we
        # were given.
        #
        ips.each do |ip|
          if ( ! run_test_internal_real( ip, port, banner, do_read ) )

            return false
            #
            # @error will be already set.
            #
          end
        end


        #
        #  All was OK
        #
        @error = nil
        return true
      end



      #
      # Run the connection test - optionally matching against the banner.
      #
      # If the banner is nil then we're merely testing we can connect and
      # send the string "quit".
      #
      # This method will ONLY ever be invoked with an IP-address for a
      # destination.
      #
      def run_test_internal_real( host, port, banner = nil, do_read = false )

        #
        # Get the timeout period for this test.
        #
        settings = Custodian::Settings.instance()
        period   = settings.timeout()

        begin
          timeout(period) do
            begin
              socket = TCPSocket.new( host, port )

              # read a banner from the remote server, if we're supposed to.
              read = nil
              read = socket.sysread(1024) if ( do_read )

              # trim to a sane length & strip newlines.
              if ( ! read.nil? )
                read = read[0,255]
                read.gsub!(/[\n\r]/, "")
              end

              socket.close()

              if ( banner.nil? )
                @error = nil
                return true
              else
                # test for banner

                # regexp.
                if ( banner.kind_of? Regexp )
                  if ( ( !read.nil? ) && ( banner.match(read) ) )
                    return true
                  end
                end

                # string.
                if ( banner.kind_of? String )
                  if ( ( !read.nil? ) && ( read =~ /#{banner}/i ) )
                    return true
                  end
                end

                @error = "We expected a banner matching '#{banner}' but we got '#{read}'"
                return false
              end
            rescue
              @error = "Exception connecting to host #{host}:#{port} - #{$!}"
              return false
            end
          end
        rescue Timeout::Error => e
          @error = "TIMEOUT: #{e}"
          return false
        end
        @error = "Misc failure"
        return false
      end




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




      register_test_type "tcp"




    end
  end
end