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
|
require 'custodian/settings'
require 'custodian/testfactory'
require 'custodian/util/dns'
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
if line =~ /for\s+([^\s]+)\sresolving\s([A-Z]+)\s+as\s'([^']+)'/
@resolve_name = $1.dup
@resolve_type = $2.dup
@resolve_expected = $3.dup.downcase.split(/[\s,]+/)
end
@server_ip = nil
#
# Ensure we had all the data.
#
raise ArgumentError, 'Missing host to resolve' unless @resolve_name
raise ArgumentError, 'Missing type of record to lookup' unless @resolve_type
raise ArgumentError, 'Missing expected results' unless @resolve_expected
raise ArgumentError, "Uknown record type: #{@resolve_type}" unless @resolve_type =~ /^(A|NS|MX|AAAA)$/
#
# 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
#
# Get the timeout period.
#
settings = Custodian::Settings.instance
period = settings.timeout
#
# Do the lookup
#
results = resolve_via(@host, resolve_type, resolve_name, period)
return Custodian::TestResult::TEST_FAILED 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.
#
if !(results - @resolve_expected).empty? or !(@resolve_expected - results).empty?
@error = "DNS server *#{@host}* (#{@server_ip}) returned the wrong records for @#{resolve_name} IN #{resolve_type}@.\n\nWe expected '#{resolve_expected.join(',')}', but we received '#{results.join(',')}'\n"
return Custodian::TestResult::TEST_FAILED
end
#
# We were valid.
#
@error = ''
Custodian::TestResult::TEST_PASSED
end
#
# Resolve an IP
#
def resolve_via(server, ltype, name, period)
results = []
begin
timeout(period) do
begin
#
# Lookup the server IP address first, and record it in an instance variable so we can use it later.
#
@server_ip = Custodian::Util::DNS.hostname_to_ip(server)
if @server_ip.nil?
@error = "Could not resolve DNS server #{server}"
return nil
end
Resolv::DNS.open(:nameserver => [@server_ip]) 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 StandardError => 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, sort, uniq
#
results.flatten.map { |r| r.to_s.downcase }.sort.uniq
end
#
# If the test fails then report the error.
#
def error
@error
end
register_test_type 'dns'
end
end
end
|