From f8aa8da864bf74bf2484b31ed4e20b6be314da5a Mon Sep 17 00:00:00 2001
From: Emmanuel Roullit <emmanuel@netsniff-ng.org>
Date: Fri, 16 Dec 2011 18:36:47 +0100
Subject: [PATCH] Added BPF attach/detach support check.

---
 src/CMakeLists.txt                     |  1 +
 src/cmake/modules/CheckBPFAttach.cmake | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+)
 create mode 100644 src/cmake/modules/CheckBPFAttach.cmake

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 99e4f52f..a4dab8b4 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -8,6 +8,7 @@ SET(CONFIG_INSTALL_PATH /etc/netsniff-ng)
 
 SET(VERSION "0.5.6")
 
+INCLUDE(CheckBPFAttach)
 INCLUDE(CheckPFPacket)
 INCLUDE(CheckStrictAlign)
 INCLUDE(CheckTxRing)
diff --git a/src/cmake/modules/CheckBPFAttach.cmake b/src/cmake/modules/CheckBPFAttach.cmake
new file mode 100644
index 00000000..f9b28dd3
--- /dev/null
+++ b/src/cmake/modules/CheckBPFAttach.cmake
@@ -0,0 +1,33 @@
+
+INCLUDE(CheckCSourceRuns)
+      
+CHECK_C_SOURCE_RUNS("
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <linux/filter.h>
+
+int
+main(int argc, char *argv[])
+{
+	struct sock_fprog bpf;
+	int empty;
+	int sock = 0;
+
+	memset(&bpf, 0, sizeof(bpf));
+
+	setsockopt(sock, SOL_SOCKET, SO_ATTACH_FILTER, &bpf, sizeof(bpf));
+	setsockopt(sock, SOL_SOCKET, SO_DETACH_FILTER, &empty, sizeof(empty));
+	exit(0);
+}
+"
+	BPFATTACH_RUN_RESULT)
+
+SET(HAVE_BPF_ATTACH NO)
+IF(BPFATTACH_RUN_RESULT EQUAL 1)
+    SET(HAVE_BPF_ATTACH YES)
+    MESSAGE(STATUS "System has SO_ATTACH_FILTER/SO_DETACH_FILTER support")
+ELSE(BPFATTACH_RUN_RESULT EQUAL 1)
+    MESSAGE(STATUS "System does not have SO_ATTACH_FILTER/SO_DETACH_FILTER support")
+ENDIF(BPFATTACH_RUN_RESULT EQUAL 1)
-- 
2.11.4.GIT