Make libpcap / WinPcap / Npcap optional (#2057)

Author: seladb

.github/workflows/build_and_test.yml

@@ -246,6 +246,67 @@ jobs:
           path: ${{ env.CCACHE_DIR }}
           key: ${{ steps.ccache-restore.outputs.cache-primary-key }}
 
+  libpcap-free:
+    runs-on: ubuntu-latest
+    container: seladb/ubuntu2404
+    env:
+      image: ubuntu2404
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+
+      # Checkout is performed out of the container and doesn't match our user
+      - name: Fix checkout ownership
+        run: chown -R "$(id -u):$(id -g)" "$GITHUB_WORKSPACE"
+
+      - name: Restore Ccache
+        id: ccache-restore
+        uses: actions/cache/restore@cdf6c1fa76f9f475f3d7449005a359c84ca0f306 # v5.0.3
+        with:
+          path: |
+            ${{ env.CCACHE_DIR }}
+            !*.gcda
+            !*.gcno
+          key: ${{ env.image }}-ccache-${{ github.run_id }}
+          restore-keys: |
+            ${{ env.image }}-ccache
+
+      - name: Configure PcapPlusPlus
+        run: cmake -DPCAPPP_BUILD_COVERAGE=ON -DPCAPPP_USE_PCAP=OFF -S . -B "$BUILD_DIR"
+
+      - name: Build PcapPlusPlus
+        run: cmake --build "$BUILD_DIR" -j
+
+      - name: Prepare environment for tests
+        run: |
+          python3 -m venv .venv
+          . .venv/bin/activate
+          python3 -m pip install -r ci/run_tests/requirements.txt
+
+      - name: Test PcapPlusPlus
+        run: |
+          . .venv/bin/activate
+          python3 ci/run_tests/run_tests.py --interface eth0
+
+      - name: Check installation
+        run: |
+          cmake -DPCAPPP_BUILD_COVERAGE=OFF -S . -B "$BUILD_DIR"
+          cmake --build "$BUILD_DIR" -j
+          cmake --install "$BUILD_DIR"
+
+      - name: Test Examples
+        run: |
+          . .venv/bin/activate
+          cd Tests/ExamplesTest
+          python3 -m pip install -r requirements.txt
+          python3 -m pytest --interface eth0 --root-path=../../Dist/examples_bin -m no_pcap
+
+      - name: Save Ccache
+        uses: actions/cache/save@cdf6c1fa76f9f475f3d7449005a359c84ca0f306 # v5.0.3
+        with:
+          path: ${{ env.CCACHE_DIR }}
+          key: ${{ steps.ccache-restore.outputs.cache-primary-key }}
+
   dpdk:
     runs-on: ubuntu-latest
     container: seladb/${{ matrix.image }}

CMakeLists.txt

@@ -163,6 +163,7 @@ cmake_dependent_option(
   "PCAPPP_USE_DPDK"
   OFF
 )
+option(PCAPPP_USE_PCAP "Setup PcapPlusPlus with libpcap / WinPcap / Npcap" ON)
 option(PCAPPP_USE_PF_RING "Setup PcapPlusPlus with PF_RING. In this case you must also set PF_RING_ROOT")
 option(PCAPPP_USE_XDP "Setup PcapPlusPlus with XDP")
 option(PCAPPP_USE_WINDIVERT "Setup PcapPlusPlus with WinDivert")
@@ -210,26 +211,30 @@ endif()
 
 # Required dependencies only for PCap++ project.
 if(PCAPPP_BUILD_PCAPPP)
-  # Usually on Windows PCAP_ROOT and Packet_ROOT are at the same location
-  if(WIN32 AND PCAP_ROOT AND NOT Packet_ROOT)
-    set(Packet_ROOT ${PCAP_ROOT})
-  endif()
+  # PCAP/Npcap/WinPcap is optional and controlled by PCAPPP_USE_PCAP
+  if(PCAPPP_USE_PCAP)
+    # Usually on Windows PCAP_ROOT and Packet_ROOT are at the same location
+    if(WIN32 AND PCAP_ROOT AND NOT Packet_ROOT)
+      set(Packet_ROOT ${PCAP_ROOT})
+    endif()
 
-  find_package(PCAP)
-  if(NOT PCAP_FOUND)
-    if(WIN32)
-      message(FATAL_ERROR "Please specify Npcap/WinPcap SDK directory with -DPCAP_ROOT=<PCAP_SDK_PATH>")
-    else()
-      message(FATAL_ERROR "PCAP library not found!")
+    find_package(PCAP)
+    if(NOT PCAP_FOUND)
+      if(WIN32)
+        message(FATAL_ERROR "Please specify Npcap/WinPcap SDK directory with -DPCAP_ROOT=<PCAP_SDK_PATH>")
+      else()
+        message(FATAL_ERROR "PCAP library not found!")
+      endif()
     endif()
-  endif()
 
-  # Look for Packet
-  if(WIN32)
-    find_package(Packet)
-    if(NOT Packet_FOUND)
-      message(FATAL_ERROR "Please specify Packet library -DPacket_ROOT=<NPCAP_SDK_PATH>")
+    # Look for Packet
+    if(WIN32)
+      find_package(Packet)
+      if(NOT Packet_FOUND)
+        message(FATAL_ERROR "Please specify Packet library -DPacket_ROOT=<NPCAP_SDK_PATH>")
+      endif()
     endif()
+    add_compile_definitions(USE_PCAP)
   endif()
 
   if(HAVE_PCAP_IMMEDIATE_MODE)
@@ -379,10 +384,12 @@ if(PCAPPP_INSTALL)
     install(FILES "${CMAKE_CURRENT_BINARY_DIR}/PcapPlusPlus.pc" DESTINATION "${CMAKE_INSTALL_LIBDIR}/pkgconfig")
   endif()
 
-  # CMake helpers to compile Pcap++ with CMake
-  pcapp_install_cmake_module(PCAP)
-  if(WIN32)
-    pcapp_install_cmake_module(Packet)
+  # CMake helpers to compile Pcap++ with CMake (only if PCAP is used)
+  if(PCAPPP_USE_PCAP)
+    pcapp_install_cmake_module(PCAP)
+    if(WIN32)
+      pcapp_install_cmake_module(Packet)
+    endif()
   endif()
 
   if(PCAPPP_USE_PF_RING)

Examples/CMakeLists.txt

@@ -20,26 +20,24 @@ else()
   message(STATUS "Include dir: ${PcapPlusPlus_INCLUDE_DIR}")
 endif()
 
-add_subdirectory(Arping)
-add_subdirectory(ArpSpoofing)
-add_subdirectory(DNSResolver)
-add_subdirectory(DnsSpoofing)
-add_subdirectory(HttpAnalyzer)
-add_subdirectory(IcmpFileTransfer)
-add_subdirectory(IPDefragUtil)
-add_subdirectory(IPFragUtil)
-add_subdirectory(PcapPlusPlus-benchmark)
 add_subdirectory(PcapPrinter)
 add_subdirectory(PcapSearch)
 add_subdirectory(PcapSplitter)
-add_subdirectory(SSLAnalyzer)
-add_subdirectory(TcpReassembly)
-add_subdirectory(TLSFingerprinting)
 add_subdirectory(X509Toolkit)
 
-if(PCAPPP_BUILD_TUTORIALS)
-  set(PCAPPP_BINARY_TUTORIAL_DIR ${CMAKE_BINARY_DIR}/tutorials_bin)
-  add_subdirectory(Tutorials)
+if(PCAPPP_USE_PCAP)
+  add_subdirectory(Arping)
+  add_subdirectory(ArpSpoofing)
+  add_subdirectory(DNSResolver)
+  add_subdirectory(DnsSpoofing)
+  add_subdirectory(HttpAnalyzer)
+  add_subdirectory(IcmpFileTransfer)
+  add_subdirectory(IPDefragUtil)
+  add_subdirectory(IPFragUtil)
+  add_subdirectory(PcapPlusPlus-benchmark)
+  add_subdirectory(SSLAnalyzer)
+  add_subdirectory(TcpReassembly)
+  add_subdirectory(TLSFingerprinting)
 endif()
 
 if(PCAPPP_USE_DPDK)
@@ -57,3 +55,8 @@ endif()
 if(PCAPPP_USE_XDP)
   add_subdirectory(XdpExample-FilterTraffic)
 endif()
+
+if(PCAPPP_BUILD_TUTORIALS)
+  set(PCAPPP_BINARY_TUTORIAL_DIR ${CMAKE_BINARY_DIR}/tutorials_bin)
+  add_subdirectory(Tutorials)
+endif()

Pcap++/CMakeLists.txt

@@ -1,26 +1,26 @@
 add_library(
   Pcap++
-  src/DeviceUtils.cpp
+  $<$<BOOL:${PCAPPP_USE_PCAP}>:src/DeviceUtils.cpp>
   $<$<BOOL:${PCAPPP_USE_DPDK}>:src/DpdkDevice.cpp>
   $<$<BOOL:${PCAPPP_USE_DPDK}>:src/DpdkDeviceList.cpp>
   $<$<BOOL:${PCAPPP_USE_DPDK_KNI}>:src/KniDevice.cpp>
   $<$<BOOL:${PCAPPP_USE_DPDK_KNI}>:src/KniDeviceList.cpp>
   $<$<BOOL:${LINUX}>:src/LinuxNicInformationSocket.cpp>
   $<$<BOOL:${PCAPPP_USE_DPDK}>:src/MBufRawPacket.cpp>
-  src/PcapUtils.cpp
-  src/NetworkUtils.cpp
+  $<$<BOOL:${PCAPPP_USE_PCAP}>:src/PcapUtils.cpp>
+  $<$<BOOL:${PCAPPP_USE_PCAP}>:src/NetworkUtils.cpp>
   src/PcapFileDevice.cpp
-  src/PcapDevice.cpp
+  $<$<BOOL:${PCAPPP_USE_PCAP}>:src/PcapDevice.cpp>
   src/PcapFilter.cpp
-  src/PcapLiveDevice.cpp
-  src/PcapLiveDeviceList.cpp
-  $<$<BOOL:${WIN32}>:src/PcapRemoteDevice.cpp>
-  $<$<BOOL:${WIN32}>:src/PcapRemoteDeviceList.cpp>
+  $<$<BOOL:${PCAPPP_USE_PCAP}>:src/PcapLiveDevice.cpp>
+  $<$<BOOL:${PCAPPP_USE_PCAP}>:src/PcapLiveDeviceList.cpp>
+  $<$<AND:$<BOOL:${WIN32}>,$<BOOL:${PCAPPP_USE_PCAP}>>:src/PcapRemoteDevice.cpp>
+  $<$<AND:$<BOOL:${WIN32}>,$<BOOL:${PCAPPP_USE_PCAP}>>:src/PcapRemoteDeviceList.cpp>
   $<$<BOOL:${PCAPPP_USE_PF_RING}>:src/PfRingDevice.cpp>
   $<$<BOOL:${PCAPPP_USE_PF_RING}>:src/PfRingDeviceList.cpp>
   $<$<BOOL:${PCAPPP_USE_XDP}>:src/XdpDevice.cpp>
   src/RawSocketDevice.cpp
-  $<$<BOOL:${WIN32}>:src/WinPcapLiveDevice.cpp>
+  $<$<AND:$<BOOL:${WIN32}>,$<BOOL:${PCAPPP_USE_PCAP}>>:src/WinPcapLiveDevice.cpp>
   $<$<BOOL:${PCAPPP_USE_WINDIVERT}>:src/WinDivertDevice.cpp>
   # Force light pcapng to be link fully static
   $<TARGET_OBJECTS:light_pcapng>
@@ -63,7 +63,7 @@ if(LINUX)
   list(APPEND public_headers header/LinuxNicInformationSocket.h)
 endif()
 
-if(WIN32)
+if(WIN32 AND PCAPPP_USE_PCAP)
   list(APPEND public_headers header/PcapRemoteDevice.h header/PcapRemoteDeviceList.h header/WinPcapLiveDevice.h)
 endif()
 
@@ -76,10 +76,11 @@ target_compile_features(Pcap++ PUBLIC cxx_std_14)
 if(APPLE)
   target_link_libraries(Pcap++ PRIVATE "-framework CoreFoundation" "-framework SystemConfiguration")
 elseif(WIN32)
-  target_compile_definitions(Pcap++ PUBLIC -DHAVE_REMOTE)
-  target_compile_definitions(Pcap++ PUBLIC -DWPCAP)
   target_link_libraries(Pcap++ PRIVATE ws2_32 iphlpapi)
-  target_link_libraries(Pcap++ PUBLIC Packet::Packet)
+  if(PCAPPP_USE_PCAP)
+    target_compile_definitions(Pcap++ PUBLIC HAVE_REMOTE WPCAP)
+    target_link_libraries(Pcap++ PUBLIC Packet::Packet)
+  endif()
 endif()
 
 target_include_directories(
@@ -103,7 +104,7 @@ target_link_libraries(
     $<$<BOOL:${PCAPPP_USE_DPDK}>:DPDK::DPDK>
     $<$<BOOL:${PCAPPP_USE_XDP}>:BPF::BPF>
     $<$<BOOL:${PCAPPP_USE_WINDIVERT}>:WinDivert::WinDivert>
-    PCAP::PCAP
+    $<$<BOOL:${PCAPPP_USE_PCAP}>:PCAP::PCAP>
     Threads::Threads
 )
 

Pcap++/src/PcapFilter.cpp

@@ -9,7 +9,9 @@
 #if defined(_WIN32)
 #	include <winsock2.h>
 #endif
-#include "pcap.h"
+#ifdef USE_PCAP
+#	include "pcap.h"
+#endif
 #include "RawPacket.h"
 #include "TimespecTimeval.h"
 
@@ -22,8 +24,12 @@ namespace pcpp
 	{
 		void BpfProgramDeleter::operator()(bpf_program* ptr) const noexcept
 		{
+#ifdef USE_PCAP
 			pcap_freecode(ptr);
 			delete ptr;
+#else
+			(void)ptr;
+#endif
 		}
 	}  // namespace internal
 
@@ -99,6 +105,7 @@ namespace pcpp
 		if (m_FilterStr.empty())
 			return true;
 
+#ifdef USE_PCAP
 		// Handle uncompiled program or link type mismatch
 		if (m_CachedProgram == nullptr || linkType != static_cast<uint16_t>(m_CachedProgramLinkType))
 		{
@@ -118,13 +125,18 @@ namespace pcpp
 		pktHdr.len = packetDataLength;
 		pktHdr.ts = internal::toTimeval(timestamp);
 		return (pcap_offline_filter(m_CachedProgram.get(), &pktHdr, packetData) != 0);
+#else
+		PCPP_LOG_ERROR("pcap is not available");
+		return false;
+#endif
 	}
 
 	BpfFilterWrapper::BpfProgramUPtr BpfFilterWrapper::compileFilter(std::string const& filter, LinkLayerType linkType)
 	{
 		if (filter.empty())
 			return nullptr;
 
+#ifdef USE_PCAP
 		auto pcap = std::unique_ptr<pcap_t, internal::PcapCloseDeleter>(pcap_open_dead(linkType, DEFAULT_SNAPLEN));
 		if (pcap == nullptr)
 		{
@@ -140,6 +152,10 @@ namespace pcpp
 
 		// Reassigns ownership to a new unique_ptr with a custom deleter as it now requires specialized cleanup.
 		return BpfProgramUPtr(newProg.release());
+#else
+		PCPP_LOG_ERROR("pcap is not available");
+		return BpfProgramUPtr(nullptr);
+#endif
 	}
 
 	bool GeneralFilter::matchPacketWithFilter(RawPacket* rawPacket) const

Tests/ExamplesTest/pytest.ini

@@ -9,6 +9,8 @@ markers =
 	sslanalyzer: mark a test for SSLAnalyzer.
 	pcapsearch: mark a test for PcapSearch.
 	arping: mark a test for Arping.
-	tlsfingerprinting: mark a test for TLSFingerprinting
-	pcapsplitter: mark a test for PcapSplitter
+	tlsfingerprinting: mark a test for TLSFingerprinting.
+	pcapsplitter: mark a test for PcapSplitter.
+	x509toolkit: mark a test for X509Toolkit.
 	no_network: mark a test that does not need network connection.
+	no_pcap: mark a test that does not require libpcap / WinPcap/ Npcap.

Tests/ExamplesTest/tests/test_pcapprinter.py

@@ -6,6 +6,7 @@
 class TestPcapPrinter(ExampleTest):
     pytestmark = [pytest.mark.pcapprinter, pytest.mark.no_network]
 
+    @pytest.mark.no_pcap
     def test_sanity(self, tmpdir):
         args = {
             "": path.join("pcap_examples", "many-protocols.pcap"),
@@ -17,11 +18,13 @@ def test_sanity(self, tmpdir):
             expected_content="Finished. Printed 4709 packets",
         )
 
+    @pytest.mark.no_pcap
     def test_input_file_missing(self):
         args = {}
         completed_process = self.run_example(args=args, expected_return_code=1)
         assert "ERROR: Input file name was not given" in completed_process.stdout
 
+    @pytest.mark.no_pcap
     def test_print_count_packets(self, tmpdir):
         args = {
             "": path.join("pcap_examples", "many-protocols.pcap"),
@@ -46,6 +49,7 @@ def test_filter(self, tmpdir):
             expected_content="Finished. Printed 4666 packets",
         )
 
+    @pytest.mark.no_pcap
     def test_snoop(self, tmpdir):
         args = {
             "": path.join("pcap_examples", "solaris.snoop"),

Tests/ExamplesTest/tests/test_pcapsearch.py

@@ -52,11 +52,13 @@ def test_different_file_extensions(self):
         assert ".pcapng'" in completed_process.stdout
         assert ".pcap'" not in completed_process.stdout
 
+    @pytest.mark.no_pcap
     def test_no_args(self):
         args = {}
         completed_process = self.run_example(args=args, expected_return_code=1)
         assert "ERROR: Input directory was not given" in completed_process.stdout
 
+    @pytest.mark.no_pcap
     def test_invalid_dir(self):
         args = {"-d": "dir_that_doesnt_exist", "-s": "udp"}
         completed_process = self.run_example(args=args, expected_return_code=1)