Tutorial: Network Time Protocol (NTP)

layer 7 NTP

Introduction

This tutorial discusses the plugin ntpDecode. It is a common standard for synchronizing network equipment of all sorts.

Preparation

First, restore T2 into a pristine state by removing all unnecessary or older plugins from the plugin folder ~/.tranalyzer/plugins:

t2build -e -y

Are you sure you want to empty the plugin folder '/home/wurst/.tranalyzer/plugins' (y/N)? yes
Plugin folder emptied

Then compile the core (tranalyzer2) and the following plugins:

t2build tranalyzer2 basicFlow ntpDecode txtSink

...
BUILD SUCCESSFUL

If you did not create a separate data and results directory yet, please do it now in another bash window, that facilitates your workflow:

mkdir ~/data ~/results

The sample PCAP used in this tutorial can be downloaded here: ntp.pcap.

Please save it in your ~/data folder.

Now you are all set for analyzing NTP traffic!

ntpDecode

This plugin was originally developed for troubleshooting purposes and evolved in the last time a bit.

Let’s look at the plugin configuration first:

ntpDecode

vi src/ntpDecode.h

NTP_TS controls the output of NTP timestamps while NTP_LIVM_HEX controls the display of the leap indicator. We leave everything by default.

Now run t2 on the supplied pcap.

t2 -r ~/data/ntp.pcap -w ~/results/

================================================================================
Tranalyzer 0.8.14 (Anteater), Tarantula. PID: 13131
================================================================================
[INF] Creating flows for L2, IPv4, IPv6
Active plugins:
    01: basicFlow, 0.8.14
    02: ntpDecode, 0.8.14
    03: txtSink, 0.8.14
[INF] IPv4 Ver: 5, Rev: 16122020, Range Mode: 0, subnet ranges loaded: 406105 (406.11 K)
[INF] IPv6 Ver: 5, Rev: 17122020, Range Mode: 0, subnet ranges loaded: 51345 (51.34 K)
Processing file: /home/wurst/data/ntp.pcap
Link layer type: Ethernet [EN10MB/1]
Dump start: 1472570513.207925 sec (Tue 30 Aug 2016 15:21:53 GMT)
Dump stop : 1472572749.211326 sec (Tue 30 Aug 2016 15:59:09 GMT)
Total dump duration: 2236.003401 sec (37m 16s)
Finished processing. Elapsed time: 0.001044 sec
Finished unloading flow memory. Time: 0.001184 sec
Percentage completed: 100.00%
Number of processed packets: 38
Number of processed bytes: 3420 (3.42 K)
Number of raw bytes: 3420 (3.42 K)
Number of pcap bytes: 4052 (4.05 K)
Number of IPv4 packets: 38 [100.00%]
Number of A packets: 19 [50.00%]
Number of B packets: 19 [50.00%]
Number of A bytes: 1710 (1.71 K) [50.00%]
Number of B bytes: 1710 (1.71 K) [50.00%]
Average A packet load: 90.00
Average B packet load: 90.00
--------------------------------------------------------------------------------
ntpDecode: Aggregated ntpStat=0x01
ntpDecode: Number of NTP packets: 38 [100.00%]
--------------------------------------------------------------------------------
Headers count: min: 3, max: 3, average: 3.00
Number of UDP packets: 38 [100.00%]
Number of UDP bytes: 3420 (3.42 K) [100.00%]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Number of processed   flows: 38
Number of processed A flows: 19 [50.00%]
Number of processed B flows: 19 [50.00%]
Number of request     flows: 19 [50.00%]
Number of reply       flows: 19 [50.00%]
Total   A/B    flow asymmetry: 0.00
Total req/rply flow asymmetry: 0.00
Number of processed   packets/flows: 1.00
Number of processed A packets/flows: 1.00
Number of processed B packets/flows: 1.00
Number of processed total packets/s: 0.02
Number of processed A+B   packets/s: 0.02
Number of processed A     packets/s: 0.01
Number of processed   B   packets/s: 0.01
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Number of average processed flows/s: 0.02
Average full raw bandwidth: 12 b/s
Average full bandwidth : 12 b/s
Max number of flows in memory: 6 [0.00%]
Memory usage: 0.01 GB [0.02%]
Aggregated flowStat=0x0400000000004000
[INF] IPv4 flows

The end report detect 38 NTP packets. The aggregated ntpStat currently has only one bit which states, there is NTP.

tawk -V ntpStat=0x01

The ntpStat column with value 0x01 is to be interpreted as follows:

   bit | ntpStat | Description
   =============================================================================
     0 | 0x01    | NTP port detected

Now let’s look at the flow file. You will see all relevant information about time synchronization including stratum, precision, time stamps, etc. So you can troubleshoot whether the time synchronization works as configured.

tcol ~/results/ntp_flows.txt

%dir  flowInd  flowStat            timeFirst          timeLast           duration  numHdrDesc  numHdrs  hdrDesc       srcMac             dstMac             ethType  ethVlanID  srcIP            srcIPCC  srcIPOrg                srcPort  dstIP            dstIPCC  dstIPOrg                dstPort  l4Proto  ntpStat  ntpLi_V_M  ntpStrat  ntpRefClkId    ntpRefStrId  ntpPollInt  ntpPrec  ntpRtDelMin   ntpRtDelMax   ntpRtDispMin  ntpRtDispMax  ntpRefTS           ntpOrigTS          ntpRecTS           ntpTranTS
A     1        0x0400000000004000  1472570513.207925  1472570513.207925  0.000000  1           3        eth:ipv4:udp  e0:3f:49:7e:59:79  00:00:5e:00:01:11  0x0800              10.20.6.146      04       "Private network"       123      77.245.18.26     ch       "nexellent ag"          123      17       0x01     0_4_3      0x03      77.245.18.26                512         1        0.00453193    0.00453193    0.06161593    0.06161593    1472569999.211569  1472569999.211361  1472569999.211569  1472570513.207891
B     1        0x0400000000004001  1472570513.211535  1472570513.211535  0.000000  1           3        eth:ipv4:udp  90:e2:ba:0c:39:84  e0:3f:49:7e:59:79  0x0800              77.245.18.26     ch       "nexellent ag"          123      10.20.6.146      04       "Private network"       123      17       0x01     0_4_4      0x02      192.33.96.102               512         1        0.0009613184  0.0009613184  0.01878386    0.01878386    1472570362.242637  1472570513.207891  1472570513.211010  1472570513.211078
A     2        0x0400000000004000  1472570618.207919  1472570618.207919  0.000000  1           3        eth:ipv4:udp  e0:3f:49:7e:59:79  00:00:5e:00:01:11  0x0800              10.20.6.146      04       "Private network"       123      77.109.139.83    ch       "Init7"                 123      17       0x01     0_4_3      0x03      77.245.18.26                512         1        0.00453193    0.00453193    0.03067063    0.03067063    1472570513.211536  1472570091.211276  1472570091.211306  1472570618.207885
B     2        0x0400000000004001  1472570618.211312  1472570618.211312  0.000000  1           3        eth:ipv4:udp  90:e2:ba:0c:39:84  e0:3f:49:7e:59:79  0x0800              77.109.139.83    ch       "Init7"                 123      10.20.6.146      04       "Private network"       123      17       0x01     0_4_4      0x02      192.33.96.102               512         1        0.003860533   0.003860533   0.0301976     0.0301976     1472569796.057972  1472570618.207885  1472570618.210994  1472570618.211015
A     3        0x0400000000004000  1472570632.207919  1472570632.207919  0.000000  1           3        eth:ipv4:udp  e0:3f:49:7e:59:79  00:00:5e:00:01:11  0x0800              10.20.6.146      04       "Private network"       123      193.225.118.129  hu       "KIFU"                  123      17       0x01     0_4_3      0x03      77.245.18.26                512         1        0.00453193    0.00453193    0.03088426    0.03088426    1472570513.211536  1472570108.224029  1472570108.240425  1472570632.207887
B     3        0x0400000000004001  1472570632.240444  1472570632.240444  0.000000  1           3        eth:ipv4:udp  90:e2:ba:0c:39:84  e0:3f:49:7e:59:79  0x0800              193.225.118.129  hu       "KIFU"                  123      10.20.6.146      04       "Private network"       123      17       0x01     0_4_4      0x02      228.143.95.23               512         1        0.0005951019  0.0005951019  0.005096513   0.005096513   1472570591.047067  1472570632.207887  1472570632.223725  1472570632.223768
A     4        0x0400000000004000  1472570705.207932  1472570705.207932  0.000000  1           3        eth:ipv4:udp  e0:3f:49:7e:59:79  00:00:5e:00:01:11  0x0800              10.20.6.146      04       "Private network"       123      130.60.204.10    ch       "Universitaet Zuerich"  123      17       0x01     0_4_3      0x03      77.245.18.26                512         1        0.00453193    0.00453193    0.03198291    0.03198291    1472570513.211536  1472570180.212284  1472570180.212053  1472570705.207906
B     4        0x0400000000004001  1472570705.212115  1472570705.212115  0.000000  1           3        eth:ipv4:udp  90:e2:ba:0c:39:84  e0:3f:49:7e:59:79  0x0800              130.60.204.10    ch       "Universitaet Zuerich"  123      10.20.6.146      04       "Private network"       123      17       0x01     0_4_4      0x04      130.60.204.8                512         1        0.002197299   0.002197299   0.07370108    0.07370108    1472570312.541679  1472570705.207906  1472570705.211867  1472570705.211971
A     5        0x0400000000004000  1472571032.207897  1472571032.207897  0.000000  1           3        eth:ipv4:udp  e0:3f:49:7e:59:79  00:00:5e:00:01:11  0x0800              10.20.6.146      04       "Private network"       123      77.245.18.26     ch       "nexellent ag"          123      17       0x01     0_4_3      0x03      77.245.18.26                512         1        0.00453193    0.00453193    0.03688106    0.03688106    1472570513.211536  1472570513.211078  1472570513.211536  1472571032.207868
B     5        0x0400000000004001  1472571032.211551  1472571032.211551  0.000000  1           3        eth:ipv4:udp  90:e2:ba:0c:39:84  e0:3f:49:7e:59:79  0x0800              77.245.18.26     ch       "nexellent ag"          123      10.20.6.146      04       "Private network"       123      17       0x01     0_4_4      0x02      192.33.96.102               512         1        0.0009613184  0.0009613184  0.02656596    0.02656596    1472570362.242637  1472571032.207868  1472571032.210783  1472571032.210863
A     6        0x0400000000004000  1472571132.207904  1472571132.207904  0.000000  1           3        eth:ipv4:udp  e0:3f:49:7e:59:79  00:00:5e:00:01:11  0x0800              10.20.6.146      04       "Private network"       123      77.109.139.83    ch       "Init7"                 123      17       0x01     0_4_3      0x03      77.245.18.26                512         1        0.00453193    0.00453193    0.0383917     0.0383917     1472570513.211536  1472570618.211015  1472570618.211313  1472571132.207872
B     6        0x0400000000004001  1472571132.211246  1472571132.211246  0.000000  1           3        eth:ipv4:udp  90:e2:ba:0c:39:84  e0:3f:49:7e:59:79  0x0800              77.109.139.83    ch       "Init7"                 123      10.20.6.146      04       "Private network"       123      17       0x01     0_4_4      0x02      192.33.96.102               512         1        0.003860533   0.003860533   0.03790341    0.03790341    1472569796.057972  1472571132.207872  1472571132.210707  1472571132.210740
A     7        0x0400000000004000  1472571173.207923  1472571173.207923  0.000000  1           3        eth:ipv4:udp  e0:3f:49:7e:59:79  00:00:5e:00:01:11  0x0800              10.20.6.146      04       "Private network"       123      193.225.118.129  hu       "KIFU"                  123      17       0x01     0_4_3      0x03      77.245.18.26                512         1        0.00453193    0.00453193    0.03900206    0.03900206    1472570513.211536  1472570632.223768  1472570632.240444  1472571173.207881
B     7        0x0400000000004001  1472571173.240507  1472571173.240507  0.000000  1           3        eth:ipv4:udp  90:e2:ba:0c:39:84  e0:3f:49:7e:59:79  0x0800              193.225.118.129  hu       "KIFU"                  123      10.20.6.146      04       "Private network"       123      17       0x01     0_4_4      0x02      228.143.95.23               512         1        0.0005798428  0.0005798428  0.009277485   0.009277485   1472570657.047002  1472571173.207881  1472571173.223569  1472571173.223611
A     8        0x0400000000004000  1472571238.207912  1472571238.207912  0.000000  1           3        eth:ipv4:udp  e0:3f:49:7e:59:79  00:00:5e:00:01:11  0x0800              10.20.6.146      04       "Private network"       123      130.60.204.10    ch       "Universitaet Zuerich"  123      17       0x01     0_4_3      0x03      77.245.18.26                512         1        0.00453193    0.00453193    0.03997864    0.03997864    1472570513.211536  1472570705.211971  1472570705.212116  1472571238.207879
B     8        0x0400000000004001  1472571238.212333  1472571238.212333  0.000000  1           3        eth:ipv4:udp  90:e2:ba:0c:39:84  e0:3f:49:7e:59:79  0x0800              130.60.204.10    ch       "Universitaet Zuerich"  123      10.20.6.146      04       "Private network"       123      17       0x01     0_4_4      0x04      130.60.205.7                512         1        0.002014191   0.002014191   0.07621881    0.07621881    1472570950.541664  1472571238.207879  1472571238.211619  1472571238.211725
A     9        0x0400000000004000  1472571559.207906  1472571559.207906  0.000000  1           3        eth:ipv4:udp  e0:3f:49:7e:59:79  00:00:5e:00:01:11  0x0800              10.20.6.146      04       "Private network"       123      77.245.18.26     ch       "nexellent ag"          123      17       0x01     0_4_3      0x03      77.245.18.26                512         1        0.00453193    0.00453193    0.04478523    0.04478523    1472570513.211536  1472571032.210863  1472571032.211552  1472571559.207875
B     9        0x0400000000004001  1472571559.211524  1472571559.211524  0.000000  1           3        eth:ipv4:udp  90:e2:ba:0c:39:84  e0:3f:49:7e:59:79  0x0800              77.245.18.26     ch       "nexellent ag"          123      10.20.6.146      04       "Private network"       123      17       0x01     0_4_4      0x02      192.33.96.102               512         1        0.0009613184  0.0009613184  0.03447013    0.03447013    1472570362.242637  1472571559.207875  1472571559.210827  1472571559.210926
A     10       0x0400000000004000  1472571673.207910  1472571673.207910  0.000000  1           3        eth:ipv4:udp  e0:3f:49:7e:59:79  00:00:5e:00:01:11  0x0800              10.20.6.146      04       "Private network"       123      77.109.139.83    ch       "Init7"                 123      17       0x01     0_4_3      0x03      77.245.18.26                512         1        0.004501412   0.004501412   0.04644846    0.04644846    1472571559.211524  1472571132.210740  1472571132.211247  1472571673.207877
B     10       0x0400000000004001  1472571673.211296  1472571673.211296  0.000000  1           3        eth:ipv4:udp  90:e2:ba:0c:39:84  e0:3f:49:7e:59:79  0x0800              77.109.139.83    ch       "Init7"                 123      10.20.6.146      04       "Private network"       123      17       0x01     0_4_4      0x02      36.224.68.195               512         1        0.009536888   0.009536888   0.03100633    0.03100633    1472571055.903184  1472571673.207877  1472571673.210864  1472571673.210889
A     11       0x0400000000004000  1472571688.207908  1472571688.207908  0.000000  1           3        eth:ipv4:udp  e0:3f:49:7e:59:79  00:00:5e:00:01:11  0x0800              10.20.6.146      04       "Private network"       123      193.225.118.129  hu       "KIFU"                  123      17       0x01     0_4_3      0x03      77.245.18.26                512         1        0.004501412   0.004501412   0.04667735    0.04667735    1472571559.211524  1472571173.223611  1472571173.240508  1472571688.207881
B     11       0x0400000000004001  1472571688.240453  1472571688.240453  0.000000  1           3        eth:ipv4:udp  90:e2:ba:0c:39:84  e0:3f:49:7e:59:79  0x0800              193.225.118.129  hu       "KIFU"                  123      10.20.6.146      04       "Private network"       123      17       0x01     0_4_4      0x02      228.143.95.23               512         1        0.0005951019  0.0005951019  0.006424048   0.006424048   1472571517.047096  1472571688.207881  1472571688.223647  1472571688.223687
A     12       0x0400000000004000  1472571758.207963  1472571758.207963  0.000000  1           3        eth:ipv4:udp  e0:3f:49:7e:59:79  00:00:5e:00:01:11  0x0800              10.20.6.146      04       "Private network"       123      130.60.204.10    ch       "Universitaet Zuerich"  123      17       0x01     0_4_3      0x03      77.245.18.26                512         1        0.004501412   0.004501412   0.04773022    0.04773022    1472571559.211524  1472571238.211725  1472571238.212334  1472571758.207917
B     12       0x0400000000004001  1472571758.212042  1472571758.212042  0.000000  1           3        eth:ipv4:udp  90:e2:ba:0c:39:84  e0:3f:49:7e:59:79  0x0800              130.60.204.10    ch       "Universitaet Zuerich"  123      10.20.6.146      04       "Private network"       123      17       0x01     0_4_4      0x04      130.60.205.7                512         1        0.002014191   0.002014191   0.08403143    0.08403143    1472570950.541664  1472571758.207917  1472571758.211324  1472571758.211429
A     13       0x0400000000004000  1472572098.207900  1472572098.207900  0.000000  1           3        eth:ipv4:udp  e0:3f:49:7e:59:79  00:00:5e:00:01:11  0x0800              10.20.6.146      04       "Private network"       123      77.245.18.26     ch       "nexellent ag"          123      17       0x01     0_4_3      0x03      77.245.18.26                512         1        0.004501412   0.004501412   0.05282673    0.05282673    1472571559.211524  1472571559.210926  1472571559.211524  1472572098.207872
B     13       0x0400000000004001  1472572098.211679  1472572098.211679  0.000000  1           3        eth:ipv4:udp  90:e2:ba:0c:39:84  e0:3f:49:7e:59:79  0x0800              77.245.18.26     ch       "nexellent ag"          123      10.20.6.146      04       "Private network"       123      17       0x01     0_4_4      0x02      192.33.96.102               512         1        0.0009613184  0.0009613184  0.04255741    0.04255741    1472570362.242637  1472572098.207872  1472572098.210856  1472572098.211036
A     14       0x0400000000004000  1472572213.207905  1472572213.207905  0.000000  1           3        eth:ipv4:udp  e0:3f:49:7e:59:79  00:00:5e:00:01:11  0x0800              10.20.6.146      04       "Private network"       123      193.225.118.129  hu       "KIFU"                  123      17       0x01     0_4_3      0x03      77.245.18.26                512         1        0.004501412   0.004501412   0.054551      0.054551      1472571559.211524  1472571688.223687  1472571688.240453  1472572213.207876
B     14       0x0400000000004001  1472572213.240438  1472572213.240438  0.000000  1           3        eth:ipv4:udp  90:e2:ba:0c:39:84  e0:3f:49:7e:59:79  0x0800              193.225.118.129  hu       "KIFU"                  123      10.20.6.146      04       "Private network"       123      17       0x01     0_4_4      0x02      228.143.95.23               512         1        0.0005645838  0.0005645838  0.009735256   0.009735256   1472571715.047003  1472572213.207876  1472572213.223584  1472572213.223626
A     15       0x0400000000004000  1472572216.207903  1472572216.207903  0.000000  1           3        eth:ipv4:udp  e0:3f:49:7e:59:79  00:00:5e:00:01:11  0x0800              10.20.6.146      04       "Private network"       123      77.109.139.83    ch       "Init7"                 123      17       0x01     0_4_3      0x03      77.245.18.26                512         1        0.004501412   0.004501412   0.05459678    0.05459678    1472571559.211524  1472571673.210889  1472571673.211297  1472572216.207873
B     15       0x0400000000004001  1472572216.211180  1472572216.211180  0.000000  1           3        eth:ipv4:udp  90:e2:ba:0c:39:84  e0:3f:49:7e:59:79  0x0800              77.109.139.83    ch       "Init7"                 123      10.20.6.146      04       "Private network"       123      17       0x01     0_4_4      0x02      36.224.68.195               512         1        0.009536888   0.009536888   0.03915465    0.03915465    1472571055.903184  1472572216.207873  1472572216.210727  1472572216.210749
A     16       0x0400000000004000  1472572288.207935  1472572288.207935  0.000000  1           3        eth:ipv4:udp  e0:3f:49:7e:59:79  00:00:5e:00:01:11  0x0800              10.20.6.146      04       "Private network"       123      130.60.204.10    ch       "Universitaet Zuerich"  123      17       0x01     0_4_3      0x03      77.245.18.26                512         1        0.004501412   0.004501412   0.05568017    0.05568017    1472571559.211524  1472571758.211429  1472571758.212043  1472572288.207892
B     16       0x0400000000004001  1472572288.212004  1472572288.212004  0.000000  1           3        eth:ipv4:udp  90:e2:ba:0c:39:84  e0:3f:49:7e:59:79  0x0800              130.60.204.10    ch       "Universitaet Zuerich"  123      10.20.6.146      04       "Private network"       123      17       0x01     0_4_4      0x04      130.60.159.7                512         1        0.003051804   0.003051804   0.07574578    0.07574578    1472571694.542394  1472572288.207892  1472572288.210963  1472572288.211098
A     17       0x0400000000004000  1472572618.207949  1472572618.207949  0.000000  1           3        eth:ipv4:udp  e0:3f:49:7e:59:79  00:00:5e:00:01:11  0x0800              10.20.6.146      04       "Private network"       123      77.245.18.26     ch       "nexellent ag"          123      17       0x01     0_4_3      0x03      77.245.18.26                512         1        0.004501412   0.004501412   0.06062409    0.06062409    1472571559.211524  1472572098.211036  1472572098.211679  1472572618.207904
B     17       0x0400000000004001  1472572618.211592  1472572618.211592  0.000000  1           3        eth:ipv4:udp  90:e2:ba:0c:39:84  e0:3f:49:7e:59:79  0x0800              77.245.18.26     ch       "nexellent ag"          123      10.20.6.146      04       "Private network"       123      17       0x01     0_4_4      0x02      192.33.96.102               512         1        0.001022354   0.001022354   0.02244602    0.02244602    1472572499.377970  1472572618.207904  1472572618.210951  1472572618.211018
A     18       0x0400000000004000  1472572746.207951  1472572746.207951  0.000000  1           3        eth:ipv4:udp  e0:3f:49:7e:59:79  00:00:5e:00:01:11  0x0800              10.20.6.146      04       "Private network"       123      193.225.118.129  hu       "KIFU"                  123      17       0x01     0_4_3      0x03      77.245.18.26                512         1        0.004501412   0.004501412   0.06254673    0.06254673    1472571559.211524  1472572213.223626  1472572213.240438  1472572746.207916
B     18       0x0400000000004001  1472572746.240517  1472572746.240517  0.000000  1           3        eth:ipv4:udp  90:e2:ba:0c:39:84  e0:3f:49:7e:59:79  0x0800              193.225.118.129  hu       "KIFU"                  123      10.20.6.146      04       "Private network"       123      17       0x01     0_4_4      0x02      228.143.95.23               512         1        0.0005493248  0.0005493248  0.004928664   0.004928664   1472572570.046974  1472572746.207916  1472572746.223698  1472572746.223740
A     19       0x0400000000004000  1472572749.207920  1472572749.207920  0.000000  1           3        eth:ipv4:udp  e0:3f:49:7e:59:79  00:00:5e:00:01:11  0x0800              10.20.6.146      04       "Private network"       123      77.109.139.83    ch       "Init7"                 123      17       0x01     0_4_3      0x03      77.245.18.26                512         1        0.004501412   0.004501412   0.06259251    0.06259251    1472571559.211524  1472572216.210749  1472572216.211181  1472572749.207888
B     19       0x0400000000004001  1472572749.211326  1472572749.211326  0.000000  1           3        eth:ipv4:udp  90:e2:ba:0c:39:84  e0:3f:49:7e:59:79  0x0800              77.109.139.83    ch       "Init7"                 123      10.20.6.146      04       "Private network"       123      17       0x01     0_4_4      0x02      192.33.96.102               512         1        0.003845274   0.003845274   0.03022812    0.03022812    1472571916.912230  1472572749.207888  1472572749.210904  1472572749.210928

Conclusion

Don’t forget to reset the plugin configuration for the next tutorial.

t2conf ntpDecode --reset && t2build ntpDecode

Have fun analyzing.