Look for and link with libnl. This is needed when linking with the new

libpcap 1.1.1 on Linux, when libpcap is also linked with libnl (which is
is when available).

configure

@@ -6376,6 +6376,95 @@ if test "$ac_res" != no; then :
 fi
 
 
+# libpcap can require libnl
+{ $as_echo "$as_me:$LINENO: checking for library containing nl_handle_alloc" >&5
+$as_echo_n "checking for library containing nl_handle_alloc... " >&6; }
+if test "${ac_cv_search_nl_handle_alloc+set}" = set; then
+  $as_echo_n "(cached) " >&6
+else
+  ac_func_search_save_LIBS=$LIBS
+cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+/* Override any GCC internal prototype to avoid an error.
+   Use char because int might match the return type of a GCC
+   builtin and then its argument prototype would still apply.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+char nl_handle_alloc ();
+int
+main ()
+{
+return nl_handle_alloc ();
+  ;
+  return 0;
+}
+_ACEOF
+for ac_lib in '' nl; do
+  if test -z "$ac_lib"; then
+    ac_res="none required"
+  else
+    ac_res=-l$ac_lib
+    LIBS="-l$ac_lib  $ac_func_search_save_LIBS"
+  fi
+  rm -f conftest.$ac_objext conftest$ac_exeext
+if { (ac_try="$ac_link"
+case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval ac_try_echo="\"\$as_me:$LINENO: $ac_try_echo\""
+$as_echo "$ac_try_echo") >&5
+  (eval "$ac_link") 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } && {
+	 test -z "$ac_c_werror_flag" ||
+	 test ! -s conftest.err
+       } && test -s conftest$ac_exeext && {
+	 test "$cross_compiling" = yes ||
+	 $as_test_x conftest$ac_exeext
+       }; then
+  ac_cv_search_nl_handle_alloc=$ac_res
+else
+  $as_echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+
+fi
+
+rm -rf conftest.dSYM
+rm -f core conftest.err conftest.$ac_objext conftest_ipa8_conftest.oo \
+      conftest$ac_exeext
+  if test "${ac_cv_search_nl_handle_alloc+set}" = set; then
+  break
+fi
+done
+if test "${ac_cv_search_nl_handle_alloc+set}" = set; then
+  :
+else
+  ac_cv_search_nl_handle_alloc=no
+fi
+rm conftest.$ac_ext
+LIBS=$ac_func_search_save_LIBS
+fi
+{ $as_echo "$as_me:$LINENO: result: $ac_cv_search_nl_handle_alloc" >&5
+$as_echo "$ac_cv_search_nl_handle_alloc" >&6; }
+ac_res=$ac_cv_search_nl_handle_alloc
+if test "$ac_res" != no; then
+  test "$ac_res" = "none required" || LIBS="$ac_res $LIBS"
+
+fi
+
+
 # They don't want lua
 if test "$no_lua" = "yes"; then
   CPPFLAGS="-DNOLUA $CPPFLAGS"

configure.ac

@@ -549,6 +549,9 @@ AC_HELP_STRING([--without-liblua], [Compile without lua (this will exclude all o
 # OpenSSL and NSE C modules can require dlopen
 AC_SEARCH_LIBS(dlopen, dl)
 
+# libpcap can require libnl
+AC_SEARCH_LIBS(nl_handle_alloc, nl)
+
 # They don't want lua
 if test "$no_lua" = "yes"; then
   CPPFLAGS="-DNOLUA $CPPFLAGS"