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|
-- This is a test script for tshark.
-- This script runs inside tshark.
-- FIRST run tshark with the "dns_dissector.lua" plugin, with the dns_port.pcap file,
-- and with full tree output (-V switch). Pipe that to a file named testin.txt.
-- This verify script then reads in that testin.txt.
--
-- tshark -r bogus.cap -X lua_script:<path_to_testdir>/lua/verify_dns_dissector.lua
local function testing(...)
print("---- Testing "..tostring(...).." ----")
end
local lines = {
{
"MyDNS Protocol",
"Transaction ID: 42",
"Flags: 0x0100",
"0... .... .... .... = Response: this is a query",
"[Expert Info (Chat/Request): DNS query message]",
"[DNS query message]",
"[Severity level: Chat]",
"[Group: Request]",
".000 0... .... .... = Opcode: 0",
".... ..0. .... .... = Truncated: False",
".... ...1 .... .... = Recursion desired: yes",
".... .... .0.. .... = World War Z - Reserved for future use: 0x0000",
".... .... ...0 .... = Checking disabled: False",
"Number of Questions: 1",
"Number of Answer RRs: 0",
"Number of Authority RRs: 0",
"Number of Additional RRs: 0",
"Queries",
"us.pool.ntp.org: type A (IPv4 host address) (1), class IN (Internet) (1)",
"Name: us.pool.ntp.org",
"[Name Length: 17]",
"[Label Count: 4]",
"Type: A (IPv4 host address) (1)",
"Class: IN (Internet) (1)",
},
{
"MyDNS Protocol",
"Transaction ID: 42",
"Flags: 0x8180",
"1... .... .... .... = Response: this is a response",
"[Expert Info (Chat/Response): It's a response!]",
"[It's a response!]",
"[Severity level: Chat]",
"[Group: Response]",
".000 0... .... .... = Opcode: 0",
".... .0.. .... .... = Authoritative: False",
".... ..0. .... .... = Truncated: False",
".... .... 1... .... = Recursion available: True",
".... .... .0.. .... = World War Z - Reserved for future use: 0x0000",
".... .... ..0. .... = Authenticated: no",
".... .... .... 0000 = Response code: No Error (0)",
".... .... ...0 .... = Checking disabled: False",
"DNS answer to life, the universe, and everything",
"[Expert Info (Note/Comment): DNS answer to life, the universe, and everything]",
"[DNS answer to life, the universe, and everything]",
"[Severity level: Note]",
"[Group: Comment]",
"Number of Questions: 1",
"Number of Answer RRs: 15",
"Number of Authority RRs: 6",
"Number of Additional RRs: 2",
"Queries",
"us.pool.ntp.org: type A (IPv4 host address) (1), class IN (Internet) (1)",
"Name: us.pool.ntp.org",
"[Name Length: 17]",
"[Label Count: 4]",
"Type: A (IPv4 host address) (1)",
"Class: IN (Internet) (1)",
},
{
"MyDNS Protocol",
"Transaction ID: 43",
"Flags: 0x0100",
"0... .... .... .... = Response: this is a query",
"[Expert Info (Chat/Request): DNS query message]",
"[DNS query message]",
"[Severity level: Chat]",
"[Group: Request]",
".000 0... .... .... = Opcode: 0",
".... ..0. .... .... = Truncated: False",
".... ...1 .... .... = Recursion desired: yes",
".... .... .0.. .... = World War Z - Reserved for future use: 0x0000",
".... .... ...0 .... = Checking disabled: False",
"Number of Questions: 1",
"Number of Answer RRs: 0",
"Number of Authority RRs: 0",
"Number of Additional RRs: 0",
"Queries",
"us.pool.ntp.org: type A (IPv4 host address) (1), class IN (Internet) (1)",
"Name: us.pool.ntp.org",
"[Name Length: 17]",
"[Label Count: 4]",
"Type: A (IPv4 host address) (1)",
"Class: IN (Internet) (1)",
},
{
"MyDNS Protocol",
"Transaction ID: 43",
"Flags: 0x8180",
"1... .... .... .... = Response: this is a response",
"[Expert Info (Chat/Response): It's a response!]",
"[It's a response!]",
"[Severity level: Chat]",
"[Group: Response]",
".000 0... .... .... = Opcode: 0",
".... .0.. .... .... = Authoritative: False",
".... ..0. .... .... = Truncated: False",
".... .... 1... .... = Recursion available: True",
".... .... .0.. .... = World War Z - Reserved for future use: 0x0000",
".... .... ..0. .... = Authenticated: no",
".... .... .... 0000 = Response code: No Error (0)",
".... .... ...0 .... = Checking disabled: False",
"Number of Questions: 1",
"Number of Answer RRs: 15",
"Number of Authority RRs: 6",
"Number of Additional RRs: 2",
"Queries",
"us.pool.ntp.org: type A (IPv4 host address) (1), class IN (Internet) (1)",
"Name: us.pool.ntp.org",
"[Name Length: 17]",
"[Label Count: 4]",
"Type: A (IPv4 host address) (1)",
"Class: IN (Internet) (1)",
},
}
-- we're going to see those two sets of output twice: both by the normal
-- dissector, then the first one by the heuristic, then the second one by
-- a conversation match
local numtests = 1 + #lines[1] + #lines[2] + #lines[3] + #lines[4]
print("going to run "..numtests.." tests")
-- for an example of what we're reading through to verify, look at end of this file
print("opening file testin.txt")
local file = io.open("testin.txt", "r")
local line = file:read()
local pktidx = 1
local total = 0
local found = false
while line do
-- eat beginning whitespace
line = line:gsub("^%s+","",1)
if line:find("^Frame %d+:") then
pktidx = line:match("^Frame (%d+):")
testing("Frame "..pktidx)
pktidx = tonumber(pktidx)
if pktidx > 4 then pktidx = pktidx - 4 end
line = file:read()
elseif line:find("%[Heuristic dissector used%]") then
-- start again, because it now repeats
-- but we should not see this [Heuristic dissector used] line again
-- or it's an error in setting the conversation
if found then
error("Heuristic dissector ran twice - conversation setting not working?")
return
end
found = true
total = total + 1
line = file:read()
elseif line == lines[pktidx][1] then
-- we've matched the first line of our section
-- now verify the rest is sequential
for i, v in ipairs(lines[pktidx]) do
io.stdout:write("testing Frame "..pktidx..", line "..i.."...")
if not line then
-- ended too soon
io.stdout:write("failed!\n")
error("Ran out of file lines!")
return
end
-- eat beginning whitespace
line = line:gsub("^%s+","",1)
if line ~= v then
io.stdout:write("failed!\n")
print("Got this:'"..line.."', expected this:'"..v.."'")
error("mismatched lines!")
return
end
io.stdout:write("passed\n")
total = total + 1
line = file:read()
end
else
line = file:read()
end
end
print(total.." of "..numtests.." tests run and passed")
if total ~= numtests then
error("Did not find all our lines to test!")
return
end
print("\n-----------------------------\n")
-- must print out the following for success (the test shell sciprt looks for this)
print("All tests passed!\n\n")
----------------------------------------------------------
-- We should see something like this:
--[[
Frame 1: 75 bytes on wire (600 bits), 75 bytes captured (600 bits)
Encapsulation type: Ethernet (1)
Arrival Time: Sep 26, 2004 23:18:04.938672000 EDT
[Time shift for this packet: 0.000000000 seconds]
Epoch Time: 1096255084.938672000 seconds
[Time delta from previous captured frame: 0.000000000 seconds]
[Time delta from previous displayed frame: 0.000000000 seconds]
[Time since reference or first frame: 0.000000000 seconds]
Frame Number: 1
Frame Length: 75 bytes (600 bits)
Capture Length: 75 bytes (600 bits)
[Frame is marked: False]
[Frame is ignored: False]
[Protocols in frame: eth:ethertype:ip:udp:mydns]
Ethernet II, Src: AmbitMic_6c:40:4e (00:d0:59:6c:40:4e), Dst: Cisco-Li_82:b2:53 (00:0c:41:82:b2:53)
Destination: Cisco-Li_82:b2:53 (00:0c:41:82:b2:53)
Address: Cisco-Li_82:b2:53 (00:0c:41:82:b2:53)
.... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
.... ...0 .... .... .... .... = IG bit: Individual address (unicast)
Source: AmbitMic_6c:40:4e (00:d0:59:6c:40:4e)
Address: AmbitMic_6c:40:4e (00:d0:59:6c:40:4e)
.... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
.... ...0 .... .... .... .... = IG bit: Individual address (unicast)
Type: IP (0x0800)
Internet Protocol Version 4, Src: 192.168.50.50 (192.168.50.50), Dst: 192.168.0.1 (192.168.0.1)
Version: 4
Header Length: 20 bytes
Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00: Not-ECT (Not ECN-Capable Transport))
0000 00.. = Differentiated Services Codepoint: Default (0x00)
.... ..00 = Explicit Congestion Notification: Not-ECT (Not ECN-Capable Transport) (0x00)
Total Length: 61
Identification: 0x0a41 (2625)
Flags: 0x00
0... .... = Reserved bit: Not set
.0.. .... = Don't fragment: Not set
..0. .... = More fragments: Not set
Fragment offset: 0
Time to live: 128
Protocol: UDP (17)
Header checksum: 0x7ceb [correct]
[Good: True]
[Bad: False]
Source: 192.168.50.50 (192.168.50.50)
Destination: 192.168.0.1 (192.168.0.1)
User Datagram Protocol, Src Port: 65282 (65282), Dst Port: 65333 (65333)
Source Port: 65282 (65282)
Destination Port: 65333 (65333)
Length: 41
Checksum: 0x07a9 [validation disabled]
[Good Checksum: False]
[Bad Checksum: False]
[Stream index: 0]
MyDNS Protocol
Transaction ID: 43
Flags: 0x0100
0... .... .... .... = Response: this is a query
.000 0... .... .... = Opcode: 0
.... ..0. .... .... = Truncated: False
.... ...1 .... .... = Recursion desired: yes
.... .... .0.. .... = World War Z - Reserved for future use: 0x0000
.... .... ...0 .... = Checking disabled: False
Number of Questions: 1
Number of Answer RRs: 0
Number of Authority RRs: 0
Number of Additional RRs: 0
Queries
us.pool.ntp.org: type A (IPv4 host address) (1), class IN (Internet) (1)
Name: us.pool.ntp.org
[Name Length: 17]
[Label Count: 4]
Type: A (IPv4 host address) (1)
Class: IN (Internet) (1)
Frame 2: 540 bytes on wire (4320 bits), 540 bytes captured (4320 bits)
Encapsulation type: Ethernet (1)
Arrival Time: Sep 26, 2004 23:18:04.945618000 EDT
[Time shift for this packet: 0.000000000 seconds]
Epoch Time: 1096255084.945618000 seconds
[Time delta from previous captured frame: 0.006946000 seconds]
[Time delta from previous displayed frame: 0.006946000 seconds]
[Time since reference or first frame: 0.006946000 seconds]
Frame Number: 2
Frame Length: 540 bytes (4320 bits)
Capture Length: 540 bytes (4320 bits)
[Frame is marked: False]
[Frame is ignored: False]
[Protocols in frame: eth:ethertype:ip:udp:mydns]
Ethernet II, Src: Cisco-Li_82:b2:53 (00:0c:41:82:b2:53), Dst: AmbitMic_6c:40:4e (00:d0:59:6c:40:4e)
Destination: AmbitMic_6c:40:4e (00:d0:59:6c:40:4e)
Address: AmbitMic_6c:40:4e (00:d0:59:6c:40:4e)
.... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
.... ...0 .... .... .... .... = IG bit: Individual address (unicast)
Source: Cisco-Li_82:b2:53 (00:0c:41:82:b2:53)
Address: Cisco-Li_82:b2:53 (00:0c:41:82:b2:53)
.... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
.... ...0 .... .... .... .... = IG bit: Individual address (unicast)
Type: IP (0x0800)
Internet Protocol Version 4, Src: 192.168.0.1 (192.168.0.1), Dst: 192.168.50.50 (192.168.50.50)
Version: 4
Header Length: 20 bytes
Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00: Not-ECT (Not ECN-Capable Transport))
0000 00.. = Differentiated Services Codepoint: Default (0x00)
.... ..00 = Explicit Congestion Notification: Not-ECT (Not ECN-Capable Transport) (0x00)
Total Length: 526
Identification: 0x2153 (8531)
Flags: 0x00
0... .... = Reserved bit: Not set
.0.. .... = Don't fragment: Not set
..0. .... = More fragments: Not set
Fragment offset: 0
Time to live: 63
Protocol: UDP (17)
Header checksum: 0xa508 [correct]
[Good: True]
[Bad: False]
Source: 192.168.0.1 (192.168.0.1)
Destination: 192.168.50.50 (192.168.50.50)
User Datagram Protocol, Src Port: 65333 (65333), Dst Port: 65282 (65282)
Source Port: 65333 (65333)
Destination Port: 65282 (65282)
Length: 506
Checksum: 0xf9d5 [validation disabled]
[Good Checksum: False]
[Bad Checksum: False]
[Stream index: 0]
MyDNS Protocol
Transaction ID: 43
Flags: 0x8180
1... .... .... .... = Response: this is a response
.000 0... .... .... = Opcode: 0
.... .0.. .... .... = Authoritative: False
.... ..0. .... .... = Truncated: False
.... .... 1... .... = Recursion available: True
.... .... .0.. .... = World War Z - Reserved for future use: 0x0000
.... .... ..0. .... = Authenticated: no
.... .... .... 0000 = Response code: No Error (0)
.... .... ...0 .... = Checking disabled: False
Number of Questions: 1
Number of Answer RRs: 15
Number of Authority RRs: 6
Number of Additional RRs: 2
Queries
us.pool.ntp.org: type A (IPv4 host address) (1), class IN (Internet) (1)
Name: us.pool.ntp.org
[Name Length: 17]
[Label Count: 4]
Type: A (IPv4 host address) (1)
Class: IN (Internet) (1)
]]
|
