Running PcapPlusPlus Tests

PcapPlusPlus source code contains a set of test-cases you can run to make sure everything works correctly on your system.

These test-cases are divided into three separate projects:

[PCAPPPLUSPLUS_HOME]/Tests/Packet++Test - contains test-cases for the Packet++ library
[PCAPPPLUSPLUS_HOME]/Tests/Pcap++Test - contains test-cases (mostly) for the Pcap++ library
[PCAPPPLUSPLUS_HOME]/Tests/ExamplesTest - contains test-cases for PcapPlusPlus examples

When you build PcapPlusPlus these projects are also built. The following sections contain information on how to run the test-cases:

Packet++Test
1. Some more technical details
Pcap++Test
1. Some more technical details
ExamplesTest

Packet++Test

This project contains test-cases that mostly test the Packet++ library, meaning testing the functionality of parsing and crafting packets of different protocols.

After a successful build you can run these test-cases by following these simple steps:

The steps below are shown on Linux but apply in the same way to all supported platforms

Go to Packet++Test directory:

seladb@seladb:~/PcapPlusPlus$ cd Tests/Packet++Test/
seladb@seladb:~/PcapPlusPlus/Tests/Packet++Test$

Run the tests from this directory. The executable is inside the Bin directory:

seladb@seladb:~/PcapPlusPlus/Tests/Packet++Test$ Bin/Packet++Test 
PcapPlusPlus version: v21.11 (official release)
Built: MMM DD YYYY 02:36:16
Built from: Git branch 'master', commit '8b2d721fdaaa6af516494d96f032e10264d7bf56'
Start running tests...

EthPacketCreation             : PASSED
EthPacketPointerCreation      : PASSED
EthAndArpPacketParsing        : PASSED
ArpPacketCreation             : PASSED
VlanParseAndCreation          : PASSED
Ipv4PacketCreation            : PASSED
...
...
...
ALL TESTS PASSED!!
Test cases: 92, Passed: 92, Failed: 0, Skipped: 0

Hopefully if all tests pass you’ll see a message at the end saying ALL TESTS PASSED!! and the number of test-cases that passed, skipped or failed. You’ll also see next to each test-case whether it has passed or failed.

If a test-case failed you’ll see an appropriate assert message explaining what caused the failure, for example:

seladb@seladb:~/PcapPlusPlus/Tests/Packet++Test$ Bin/Packet++Test 
PcapPlusPlus version: v21.11 (official release)
Built: MMM DD YYYY 02:44:35
Built from: Git branch 'master', commit '8b2d721fdaaa6af516494d96f032e10264d7bf56'
Start running tests...

EthPacketCreation             : PASSED
EthPacketPointerCreation      : PASSED
EthAndArpPacketParsing        : PASSED
ArpPacketCreation             : FAILED (line: 245). assert equal failed: actual: 42 != expected: 43
VlanParseAndCreation          : PASSED
Ipv4PacketCreation            : PASSED
...
...
...
NOT ALL TESTS PASSED!!
Test cases: 92, Passed: 91, Failed: 1, Skipped: 0

Please note that it’s very important to run the tests from the Tests/Packet++Test directory (using Bin/Packet++Test) because the test-cases are using packet examples that reside in Tests/Packet++Test/PacketExamples and are assuming the running directory is Tests/Packet++Test

Some more technical details

The folder structure of Packet++Test is as follows (showing only relevant folders):
```
|- Bin/
|- PacketExamples/
|- Tests/
   |- BgpTests.cpp
   |- DhcpTests.cpp
   |- DnsTests.cpp
   |- ...
   |- ...
|- Utils/
|- main.cpp
|- Makefile
|- TestDefinition.h
|- ...
|- ...
```
The test-cases are gathered under the Tests/ folder. Each file in this folder contains a few test-cases which belong to a specific protocol or subject.

The PacketExamples/ folder contains packet examples used by the various test-cases.

Bin/ contains the executable.

Utils/ contains a few methods commonly used by the test-cases.

TestDefinition.h contains a definition of all the test-cases and main.cpp is in charge of parsing command-line arguments and running the tests.
Each test-case resides in one of the .cpp files under Packet++Test/Tests/ and has the following definition:
```
PTF_TEST_CASE(GtpLayerParsingTest)
{
    ...
    ...
}
```
In addition this test needs to be declared in Packet++Test/TestDefinition.h:
```
...
...
// Implemented in GtpTests.cpp
PTF_TEST_CASE(GtpLayerParsingTest);
...
...
```
In addition to the functional tests described in each test-case there is also a memory leak test that is being performed for each test-case separately. The MemPlumber library is being used to detect memory leaks. If a memory leak is detected the test-case will fail with an appropriate assert message

Each test-case has one or more tags assigned to it. The tags are defined when calling each test-case in Packet++Test/main.cpp. For example: PTF_RUN_TEST(EthPacketCreation, "eth") has the tag “eth” assigned to it, while PTF_RUN_TEST(SipResponseLayerCreationTest, "sip") has the “sip” tag assigned to it. In addition there is a default tag assigned to each test-case which is its name. This mechanism allows running specific tests instead of always running all of them. There is a command-line switch -t or --tags which enables running only tests that are assigned to specific tags. You should provide it a list of tags (one or more) separated by a semicolon and surrounded by quotes.

For example, the following command will run only tests that have the “eth” tag assigned to them:

seladb@seladb:~/PcapPlusPlus/Tests/Packet++Test$ Bin/Packet++Test -t "eth"
PcapPlusPlus version: v21.11 (official release)
Built: MMM DD YYYY 03:19:34
Built from: Git branch 'master', commit '8b2d721fdaaa6af516494d96f032e10264d7bf56'
Start running tests...

EthPacketCreation             : PASSED
EthPacketPointerCreation      : PASSED
EthAndArpPacketParsing        : PASSED
EthDot3LayerParsingTest       : PASSED
EthDot3LayerCreateEditTest    : PASSED

ALL TESTS PASSED!!
Test cases: 92, Passed: 5, Failed: 0, Skipped: 87

As you can see 5 test-cases matched the eth tag and the rest of them (87) were skipped and are not showing on the report.

This command will run only test-cases which have “eth” or “ipv6” tags assigned to them:

seladb@seladb:~/PcapPlusPlus/Tests/Packet++Test$ Bin/Packet++Test -t "eth;ipv6"
PcapPlusPlus version: v21.11 (official release)
Built: MMM DD YYYY 03:19:34
Built from: Git branch 'master', commit '8b2d721fdaaa6af516494d96f032e10264d7bf56'
Start running tests...

EthPacketCreation             : PASSED
EthPacketPointerCreation      : PASSED
EthAndArpPacketParsing        : PASSED
EthDot3LayerParsingTest       : PASSED
EthDot3LayerCreateEditTest    : PASSED
IPv6UdpPacketParseAndCreate   : PASSED
IPv6FragmentationTest         : PASSED
IPv6ExtensionsTest            : PASSED

ALL TESTS PASSED!!
Test cases: 92, Passed: 8, Failed: 0, Skipped: 84

This command will run only the “ArpPacketCreation” test-case:

seladb@seladb:~/PcapPlusPlus/Tests/Packet++Test$ Bin/Packet++Test -t "ArpPacketCreation"
PcapPlusPlus version: v21.11 (official release)
Built: MMM DD YYYY 03:19:34
Built from: Git branch 'master', commit '8b2d721fdaaa6af516494d96f032e10264d7bf56'
Start running tests...

ArpPacketCreation             : PASSED

ALL TESTS PASSED!!
Test cases: 92, Passed: 1, Failed: 0, Skipped: 91

Here are all of the command-line switches available for Packet++Test:

`-t`, `--tags`	Run only test-cases that match specific tags. The tag list should be separated by semicolons and surrounded by apostrophes, for example: `Bin/Packet++Test -t "eth;ipv4;ArpPacketCreation"`
`-w`, `--show-skipped-tests`	Show tests that are skipped. By default they are hidden in the final report
`-v`, `--verbose`	Run in verbose mode which emits more output in several test-cases
`-m`, `--mem-verbose`	Output verbose information on all memory allocations and releases done throughout the test-cases. This can be useful to detect memory leaks
`-s`, `--skip-mem-leak-check`	Skip memory leak test for all test-cases
`-h`, `--help`	Shows a help screen with the available command-line switches

Pcap++Test

This project contains test-cases that mostly test for the Pcap++ library, meaning testing the functionality of capturing and sending network packets, reading and writing to files, DPDK functionality, PF_RING and more. It also contains tests for massive packet parsing, TCP reassembly and IP de/fragmentation.

After a successful build you can run these test-cases by following these simple steps:

The steps below are shown on Linux but apply in the same way to all supported platforms

Make sure that network traffic is flowing to the device you’re running the tests on. This is important because some of the test-cases assume incoming packets. There is also an option to run only test-cases that don’t rely on live traffic using the -n or --no-networking command-line switch

Go to Pcap++Test directory:

seladb@seladb:~/PcapPlusPlus$ cd Tests/Pcap++Test/
seladb@seladb:~/PcapPlusPlus/Tests/Pcap++Test$

Run the tests from this directory. The executable is inside the Bin directory. If you’re running with live traffic there is a mandatory command-line switch you need to provide “-i” or “--use-ip” which is the IP address of the interface you’d like the test suite to use for capturing and sending network traffic. Make sure that network traffic is flowing to that interface:

seladb@seladb:~/PcapPlusPlus/Tests/Pcap++Test$ sudo Bin/Pcap++Test -i 10.0.0.1
PcapPlusPlus version: v21.11 (official release)
Built: MMM DD YYYY 02:36:38
Git info: Git branch 'master', commit '8b2d721fdaaa6af516494d96f032e10264d7bf56'
Using ip: 10.0.0.1
Debug mode: off
Start running tests...

TestIPAddress                 : PASSED
TestMacAddress                : PASSED
TestLRUList                   : PASSED
TestGeneralUtils              : PASSED
TestGetMacAddress             : PASSED
TestPcapFileReadWrite         : PASSED
...
...
ALL TESTS PASSED!!
Test cases: 65, Passed: 50, Failed: 0, Skipped: 15

Notice that on Linux and MacOS you might need to run with sudo
Hopefully if all test cases pass you’ll see a message at the end saying ALL TESTS PASSED!! and the number of test-cases that passed, skipped or failed. You’ll also see next to each test-case whether it has passed or failed.

If a test-case failed you’ll see an appropriate assert message explaining what caused the failure, for example:

seladb@seladb:~/PcapPlusPlus/Tests/Pcap++Test$ sudo Bin/Pcap++Test -i 10.1.1.1
PcapPlusPlus version: v21.11 (official release)
Built: MMM DD YYYY 02:36:38
Git info: Git branch 'master', commit '8b2d721fdaaa6af516494d96f032e10264d7bf56'
Using ip: 10.1.1.1
Debug mode: off
Starting tests...
Start running tests...

TestIPAddress                 : PASSED
TestLRUList                   : PASSED
TestPcapFileReadWrite         : PASSED
..
..
TestPcapLiveDeviceList        : PASSED
TestPcapLiveDeviceListSearch  : FAILED. assertion failed: Device used in this test 10.1.1.1 doesnt exist
..
..

Please note that it’s very important to run the tests from the Tests/Pcap++Test directory (using Bin/Pcap++Test) because the test-cases are using packet examples that reside in Tests/Pcap++Test/PcapExamples and are assuming the running directory is Tests/Pcap++Test
If you’re building PcapPlusPlus with DPDK there is an additional mandatory command-line parameter which is “-k” or “--dpdk-port” where you need to provide the DPDK port to use for the tests. This port is simply a number starting from 0, so if you have only one interface assigned to DPDK the port number will be 0. If you have two interfaces assigned to DPDK then you can choose either 0 or 1, and so on. Please make sure there is network traffic flowing to this interface

Some more technical details

The folder structure of Pcap++Test is as follows (showing only relevant folders):
```
|- Bin/
|- Common/
|- PcapExamples/
|- Tests/
   |- DpdkTests.cpp
   |- FileTests.cpp
   |- FilterTests.cpp
   |- ...
   |- ...
|- main.cpp
|- Makefile
|- TestDefinition.h
|- ...
|- ...
```
The test-cases are gathered under the Tests/ folder. Each file in this folder contains a few test-cases which belong to a specific subject.

The PcapExamples/ folder contains pcap files used by the various test-cases.

Bin/ contains the executable.

Common/ contains a few methods commonly used by the test-cases.

TestDefinition.h contains a definition of all the test-cases and main.cpp is in charge of parsing command-line arguments and running the tests.
Each test-case resides in one of the .cpp files under Pcap++Test/Tests/ and has the following definition:
```
PTF_TEST_CASE(TestPcapLiveDevice)
{
    ...
    ...
}
```
In addition this test needs to be declared in Pcap++Test/TestDefinition.h:
```
...
...
// Implemented in GtpTests.cpp
PTF_TEST_CASE(TestPcapLiveDevice);
...
...
```
In addition to the functional tests described in each test-case there is also a memory leak test that is being performed for each test-case separately. The MemPlumber library is being used to detect memory leaks. If a memory leak is detected the test-case will fail with an appropriate assert message
There is a tag mechanism which is similar to the one implemented in Packet++Test. Please refer to the section to learn more about this functionality

Here are all of the command-line switches available for Pcap++Test:

`-i`, `--use-ip`	IP address to use for sending and receiving packets. It’s a mandatory parameter when running the tests with live network traffic
`-d`, `--debug-mode`	Set log level to DEBUG for all test-cases
`-r`, `--remote-ip`	IPv4 address of remote machine running rpcapd to test remote capture (currently relevant only for Windows). If not provided then the IPv4 address provided in `-i` switch will be used
`-p`, `--remote-port`	Port of remote machine running rpcapd to test remote capture (currently relevant only for Windows). If not provided the default port is `12321`
`-k`, `--dpdk-port`	The DPDK NIC port to use. Required only if compiling with DPDK
`-a`, `--kni-ip`	IPv4 address for the KNI device test-cases. Relevant only for Linux systems and if compiling with DPDK and KNI. Must not be the same as any of existing network interfaces in your system. If this parameter is omitted KNI tests will be skipped
`-n`, `--no-networking`	Do not run tests that requires networking
`-t`, `--tags`	Run only test-cases that match specific tags. The tag list should be separated by semicolons and surrounded by apostrophes, for example: `Bin/Pcap++Test -t "live_device;pf_ring;TestDpdkDevice"`
`-w`, `--show-skipped-tests`	Show tests that are skipped. By default they are hidden in the final report
`-v`, `--verbose`	Run in verbose mode which emits more output in several test-cases
`-m`, `--mem-verbose`	Output verbose information on all memory allocations and releases done throughout the test-cases. This can be useful to detect memory leaks
`-s`, `--skip-mem-leak-check`	Skip memory leak test for all test-cases
`-t`, `--tags`	Run only test-cases that match specific tags. The tag list should be separated by semicolons and surrounded by apostrophes, for example: `Bin/Pcap++Test -t "live_device;pf_ring;TestDpdkDevice"`
`-h`, `--help`	Shows a help screen with the available command-line switches

ExamplesTest

This project is quite different and unique from the other two in various ways:

It doesn’t test any parts of the PcapPlusPlus library but rather the example apps that are provided with the library
It doesn’t test the apps code but rather runs them as executables and inspects their output (stdout, generated files, etc.)
This project isn’t written in C++ but rather in Python. The reason is that Python is much more “user-friendly” when it comes to running executables and inspect their output; its file and string manipulation options are much more comprehensive and advanced. You can write very little code and achieve a lot. Python also has great testing frameworks that come out-of-the-box. It is the obvious choice for these kind of tasks

Because this project is written in Python it has different requirements and setup/run procedures. First we’ll go over the requirements, then we’ll dive into the setup and finally we’ll show how to run the tests and explore the command-line options available.

Requirements

This project requires Python 3.7 or newer. It won’t run on Python 2.7.x
It has dependencies on other Python libraries described in requirements.txt. In the next section we’ll go into the details of how to install them

Setup

This section describes the steps to get to a working setup:

The steps below are shown on Linux but apply in the same way to all supported platforms

Make sure you have Python 3.7 or newer. You can check the version using the -V command line option:
```
seladb@seladb:~$ python3 -V
Python 3.8.2
```

Go into the ExamplesTest directory:

seladb@seladb:~$ cd PcapPlusPlus/Tests/ExamplesTest
seladb@seladb:~/PcapPlusPlus/Tests/ExamplesTest$

If you’d like to use venv/virtualenv (which is usually recommended in Python) create the virtual environment and activate it:

seladb@seladb:~/PcapPlusPlus/Tests/ExamplesTest$ python3 -m venv venv
seladb@seladb:~/PcapPlusPlus/Tests/ExamplesTest$ source venv/bin/activate
(venv) seladbseladb:~/PcapPlusPlus/Tests/ExamplesTest$ 

Install the dependencies described in requirements.txt:

(venv) seladb@seladb:~/PcapPlusPlus/Tests/ExamplesTest$ python3 -m pip install -r requirements.txt

Since this test suite simply runs the app executables make sure you have a working build of PcapPlusPlus and that the executables are under [PcapPlusPlus-Home]/Dist/examples

Running the tests

Once you have a working setup running the tests is pretty easy:

(venv) seladbseladb:~/PcapPlusPlus/Tests/ExamplesTest$ python3 -m pytest

Here is the output you might see:

============== test session starts ===============
platform linux -- Python 3.8.2, pytest-5.4.3, py-1.9.0, pluggy-0.13.1
rootdir: /home/seladb/PcapPlusPlus/Tests/ExamplesTest, inifile: pytest.ini
collected 57 items                               

tests/test_arping.py ss.s                  [  7%]
tests/test_dnsresolver.py x..s             [ 14%]
tests/test_httpanalyzer.py ...             [ 19%]
tests/test_ipdefragutil.py ......          [ 29%]
tests/test_ipfragutil.py .......           [ 42%]
tests/test_pcapprinter.py ....             [ 49%]
tests/test_pcapsearch.py ........          [ 63%]
tests/test_pcapsplitter.py ............... [ 89%]
tests/test_sslanalyzer.py ..               [ 92%]
tests/test_tcpreassembly.py ....           [100%]

=== 52 passed, 4 skipped, 1 xfailed in 16.06s ====

This output shows how many test-cases passed, how many failed and how many were skipped or xfailed.

As you can see currently not all of the example apps are covered. This is because some of them are difficult to test by just running the executable and need a more complex setup. In the future we'll consider increasing the coverage

This project uses pytest which is one of the most popular test frameworks for Python. It has many features and options that will not be covered in this guide, but here are the options that are most relevant for this project:

`--use-sudo`	Some of the tests rely on live network traffic and need access to a network interface. On Linux and MacOS this may require `sudo` privileges. If this flag is set the test-cases will use `sudo` to run the relevant executables. If `sudo` is required and this flag is not set these tests may fail
`--interface [interface-ip]`	Required only for tests who rely on live network traffic and need the network interface IP address to use. If this parameter is not provided these tests will be skipped
`--gateway [gateway_ip]`	A small set of tests need the default gateway IP address. If this parameter is not provided these tests will be skipped
`-m [marker]`	pytest has this concept of markers which is like tagging tests with metadata. This project uses it to tag test-cases by app or those who need/don’t need network traffic. The markers relevant to this project are described in the next table
`--markers`	Show a list of all the markers available (not all of them are specific to this project)
`--help`	Show all of `pytest` command-line options

Here are the markers that are relevant to this project:

`-m no_network`	Run only test-cases that don’t require live network traffic. This is very useful for environments where live traffic is not available or if you prefer to run tests that don’t interact with the network. The test-cases which require network traffic will be skipped
`-m pcapprinter`	Run only test-cases for PcapPrinter
`-m ipdefragutil`	Run only test-cases for IPDefragUtil
`-m ipfragutil`	Run only test-cases for IPFragUtil
`-m dnsresolver`	Run only test-cases for DNSResolver
`-m tcpreassembly`	Run only test-cases for TcpReassembly
`-m httpanalyzer`	Run only test-cases for HttpAnalyzer
`-m sslanalyzer`	Run only test-cases for SSLAnalyzer
`-m pcapsearch`	Run only test-cases for PcapSearch
`-m arping`	Run only test-cases for Arping
`-m pcapsplitter`	Run only test-cases for PcapSplitter