Npcap: support live capture "vlan" filter

Uses PacketGetInfo and NPF_GETINFO_BPFEXT to detect support of the
relevant BPF extension. Npcap SDK 1.15 will contain definitions for
SKF_AD_VLAN_TAG and other relevant constants.

diff --git a/CMakeLists.txt b/CMakeLists.txt
index b4b722bb1d27b0569dbde850588eb5b0705f0c06..a8e0ffd1b5c0a8a3660b168485d9fce2ed73c602 100644 (file)
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -609,6 +609,7 @@ include_directories(
 include(CheckFunctionExists)
 include(CMakePushCheckState)
 include(CheckSymbolExists)
+include(CheckIncludeFile)
 
 if(WIN32)
 
@@ -626,8 +627,11 @@ if(WIN32)
         #
         cmake_push_check_state()
         set(CMAKE_REQUIRED_LIBRARIES ${Packet_LIBRARIES})
+        set(CMAKE_REQUIRED_INCLUDES ${Packet_INCLUDE_DIRS})
         check_function_exists(PacketIsLoopbackAdapter HAVE_PACKET_IS_LOOPBACK_ADAPTER)
         check_function_exists(PacketGetTimestampModes HAVE_PACKET_GET_TIMESTAMP_MODES)
+        check_function_exists(PacketGetInfo HAVE_PACKET_GET_INFO)
+        check_include_file(npcap-bpf.h HAVE_NPCAP_BPF_H)
         cmake_pop_check_state()
     endif(Packet_FOUND)
 
@@ -694,7 +698,6 @@ endif()
 #   Detect available platform features
 ###################################################################
 
-include(CheckIncludeFile)
 include(CheckIncludeFiles)
 include(CheckStructHasMember)
 include(CheckTypeSize)

diff --git a/cmakeconfig.h.in b/cmakeconfig.h.in
index d38985eaa63bd23bafa13f2784af7083fba2511b..041561d6bc9d9d630ad0546525752cb8f9a77bdd 100644 (file)
--- a/cmakeconfig.h.in
+++ b/cmakeconfig.h.in
@@ -90,7 +90,10 @@
 /* Define to 1 if Packet32 API (Npcap driver) is available */
 #cmakedefine HAVE_PACKET32 1
 
-/* Define to 1 if Npcap's version.h is available */
+/* Define to 1 if Npcap BPF extension definitions are available */
+#cmakedefine HAVE_NPCAP_BPF_H 1
+
+/* Define to 1 if NPcap's version.h is available */
 #cmakedefine HAVE_VERSION_H 1
 
 /* Define to 1 if you have a POSIX-style `strerror_r' function. */
@@ -200,6 +203,9 @@
 /* Define to 1 if you have the `PacketIsLoopbackAdapter' function. */
 #cmakedefine HAVE_PACKET_IS_LOOPBACK_ADAPTER 1
 
+/* Define to 1 if you have the `PacketGetInfo' function. */
+#cmakedefine HAVE_PACKET_GET_INFO 1
+
 /* IPv6 */
 #cmakedefine INET6 1
 

diff --git a/gencode.c b/gencode.c
index 8c12099a03224f73afe567aeec7e15d7c69d8fa6..275cda2ec84c504b6b0a16e3d4d4f6b56326832d 100644 (file)
--- a/gencode.c
+++ b/gencode.c
@@ -60,6 +60,10 @@
 #endif
 
 #ifdef _WIN32
+  #ifdef HAVE_NPCAP_BPF_H
+    /* Defines BPF extensions for Npcap */
+    #include <npcap-bpf.h>
+  #endif
   #ifdef INET6
     #if defined(__MINGW32__) && defined(DEFINE_ADDITIONAL_IPV6_STUFF)
 /* IPv6 address */

diff --git a/pcap-npf.c b/pcap-npf.c
index 7054062a297c28b1b11f6cf707bac55097ceed95..4feee30cfd2be73ef52156d169d85950d4e5e1cc 100644 (file)
--- a/pcap-npf.c
+++ b/pcap-npf.c
@@ -830,6 +830,10 @@ pcap_activate_npf(pcap_t *p)
        int status = 0;
        struct bpf_insn total_insn;
        struct bpf_program total_prog;
+#ifdef HAVE_PACKET_GET_INFO
+       char oid_data_buf[PACKET_OID_DATA_LENGTH(sizeof(ULONG))] = {0};
+       PACKET_OID_DATA *oid_data_arg = (PACKET_OID_DATA *)oid_data_buf;
+#endif
 
        if (p->opt.rfmon) {
                /*
@@ -1086,6 +1090,23 @@ pcap_activate_npf(pcap_t *p)
        }
 #endif /* HAVE_PACKET_GET_TIMESTAMP_MODES */
 
+#if defined(HAVE_PACKET_GET_INFO) && defined(NPF_GETINFO_BPFEXT) && defined(SKF_AD_VLAN_TAG_PRESENT)
+
+       /* Can we generate special code for VLAN checks? */
+       oid_data_arg->Oid = NPF_GETINFO_BPFEXT;
+       oid_data_arg->Length = sizeof(ULONG);
+       if (PacketGetInfo(pw->adapter, oid_data_arg)) {
+               if (*((ULONG *)oid_data_arg->Data) >= SKF_AD_VLAN_TAG_PRESENT) {
+                       /* Yes, we can.  Request that we do so. */
+                       p->bpf_codegen_flags |= BPF_SPECIAL_VLAN_HANDLING;
+               }
+       }
+       else {
+               pcapint_fmt_errmsg_for_win32_err(p->errbuf, PCAP_ERRBUF_SIZE,
+                   GetLastError(), "Error calling PacketGetInfo");
+       }
+#endif /* HAVE_PACKET_GET_INFO */
+
        /*
         * Turn a negative snapshot value (invalid), a snapshot value of
         * 0 (unspecified), or a value bigger than the normal maximum