From d5e254d50478da4893b77bcb05694c37af961beb Mon Sep 17 00:00:00 2001
From: deltay <delta.yeh@gmail.com>
Date: Fri, 28 Oct 2011 15:22:24 +0800
Subject: [PATCH] Add pfring bpf filter, require pfring >= 5.1

---
 configure.in         | 18 ++++++++++++++++++
 src/runmode-pfring.c | 25 +++++++++++++++++++++++++
 src/source-pfring.c  | 19 +++++++++++++++++++
 src/source-pfring.h  |  3 +++
 suricata.yaml        |  2 ++
 5 files changed, 67 insertions(+)

diff --git a/configure.in b/configure.in
index 4d21e0e23e..8ef560daee 100644
--- a/configure.in
+++ b/configure.in
@@ -692,6 +692,24 @@ esac
             AC_MSG_RESULT(no)
         fi
 
+        AC_MSG_CHECKING([if pfring_set_bpf_filter is available])
+        AC_TRY_COMPILE([
+                    #include <pfring.h>
+                ],
+                [
+                    pfring *pd;
+                    pd = pfring_open("eth1", 1,  1515, 1);
+                    pfring_set_bpf_filter(pd, "tcp");
+                ],
+                [ pfring_set_bpf_filter_available=yes ], [:])
+
+        if test "$pfring_set_bpf_filter_available" = "yes"; then
+            AC_DEFINE([HAVE_PFRING_SET_BPF_FILTER],[1],[PF_RING pfring_set_bpf_filter is available])
+            AC_MSG_RESULT(yes)
+        else
+            AC_MSG_RESULT(no)
+        fi
+
         STORE_CFLAGS="${CFLAGS}"
         CFLAGS="${CFLAGS} -Werror"
         AC_MSG_CHECKING([if pfring_recv expects u_char**])
diff --git a/src/runmode-pfring.c b/src/runmode-pfring.c
index 02cad36b33..5022a56799 100644
--- a/src/runmode-pfring.c
+++ b/src/runmode-pfring.c
@@ -82,6 +82,9 @@ void PfringDerefConfig(void *conf)
 {
     PfringIfaceConfig *pfp = (PfringIfaceConfig *)conf;
     if (SC_ATOMIC_SUB(pfp->ref, 1) == 0) {
+        if (pfp->bpf_filter) {
+            SCFree(pfp->bpf_filter);
+        }
         SCFree(pfp);
     }
 }
@@ -193,6 +196,9 @@ void *ParsePfringConfig(const char *iface)
     cluster_type default_ctype = CLUSTER_ROUND_ROBIN;
     int getctype = 0;
 #endif
+#ifdef HAVE_PFRING_SET_BPF_FILTER
+    char *bpf_filter = NULL;
+#endif /* HAVE_PFRING_SET_BPF_FILTER */
 
     if (iface == NULL) {
         return NULL;
@@ -201,6 +207,7 @@ void *ParsePfringConfig(const char *iface)
     if (pfconf == NULL) {
         return NULL;
     }
+    memset(pfconf, 0, sizeof(PfringIfaceConfig));
     strlcpy(pfconf->iface, iface, sizeof(pfconf->iface));
     pfconf->threads = 1;
     pfconf->cluster_id = 1;
@@ -257,6 +264,24 @@ void *ParsePfringConfig(const char *iface)
             SCLogDebug("Going to use cluster-id %" PRId32, pfconf->cluster_id);
         }
     }
+#ifdef HAVE_PFRING_SET_BPF_FILTER
+    /*load pfring bpf filter*/
+    /* command line value has precedence */
+    if (ConfGet("bpf-filter", &bpf_filter) == 1) {
+        if (strlen(bpf_filter) > 0) {
+            pfconf->bpf_filter = SCStrdup(bpf_filter);
+            SCLogDebug("Going to use command-line provided bpf filter %s",
+                       pfconf->bpf_filter);
+        }
+    } else {
+        if (ConfGetChildValue(if_root, "bpf-filter", &bpf_filter) == 1) {
+            if (strlen(bpf_filter) > 0) {
+                pfconf->bpf_filter = SCStrdup(bpf_filter);
+                SCLogDebug("Going to use bpf filter %s", pfconf->bpf_filter);
+            }
+        }
+    }
+#endif /* HAVE_PFRING_SET_BPF_FILTER */
 
 #ifdef HAVE_PFRING_CLUSTER_TYPE
     if (ConfGet("pfring.cluster-type", &tmpctype) == 1) {
diff --git a/src/source-pfring.c b/src/source-pfring.c
index 5f1b5c5019..44999da138 100644
--- a/src/source-pfring.c
+++ b/src/source-pfring.c
@@ -126,6 +126,9 @@ typedef struct PfringThreadVars_
 #endif /* HAVE_PFRING_CLUSTER_TYPE */
     uint8_t cluster_id;
     char *interface;
+#ifdef HAVE_PFRING_SET_BPF_FILTER
+    char *bpf_filter;
+#endif /* HAVE_PFRING_SET_BPF_FILTER */
 } PfringThreadVars;
 
 /**
@@ -334,6 +337,16 @@ TmEcode ReceivePfringThreadInit(ThreadVars *tv, void *initdata, void **data) {
                 version & 0x000000FF, ptv->interface);
     }
 
+#ifdef HAVE_PFRING_SET_BPF_FILTER
+    if (pfconf->bpf_filter) {
+        ptv->bpf_filter = SCStrdup(pfconf->bpf_filter);
+        rc= pfring_set_bpf_filter(ptv->pd, ptv->bpf_filter);
+        if (rc < 0) {
+            SCLogInfo("Set PF_RING bpf filter \"%s\" failed.", ptv->bpf_filter);
+        }
+    }
+#endif /* HAVE_PFRING_SET_BPF_FILTER */
+
 /* It seems that as of 4.7.1 this is required */
 #ifdef HAVE_PFRING_ENABLE
     rc = pfring_enable_ring(ptv->pd);
@@ -383,6 +396,12 @@ TmEcode ReceivePfringThreadDeinit(ThreadVars *tv, void *data) {
     if (ptv->interface)
         SCFree(ptv->interface);
     pfring_remove_from_cluster(ptv->pd);
+#ifdef HAVE_PFRING_SET_BPF_FILTER
+    if (ptv->bpf_filter) {
+        pfring_remove_bpf_filter(ptv->pd);
+        SCFree(ptv->bpf_filter);
+    }
+#endif /* HAVE_PFRING_SET_BPF_FILTER */
     pfring_close(ptv->pd);
     return TM_ECODE_OK;
 }
diff --git a/src/source-pfring.h b/src/source-pfring.h
index 14ce12254d..ae7550f779 100644
--- a/src/source-pfring.h
+++ b/src/source-pfring.h
@@ -41,6 +41,9 @@ typedef struct PfringIfaceConfig_
     char iface[PFRING_IFACE_NAME_LENGTH];
     /* number of threads */
     int threads;
+#ifdef HAVE_PFRING_SET_BPF_FILTER
+    char *bpf_filter;
+#endif /* HAVE_PFRING_SET_BPF_FILTER */
     SC_ATOMIC_DECLARE(unsigned int, ref);
     void (*DerefFunc)(void *);
 } PfringIfaceConfig;
diff --git a/suricata.yaml b/suricata.yaml
index e73b630058..5b91b903a2 100644
--- a/suricata.yaml
+++ b/suricata.yaml
@@ -538,6 +538,8 @@ pfring:
     # Default PF_RING cluster type. PF_RING can load balance per flow or per hash.
     # This is only supported in versions of PF_RING > 4.1.1.
     cluster-type: cluster_round_robin
+    # bpf filter for this interface
+    #bpf-filter: tcp
   # Second interface
   #- interface: eth1
   #  threads: 3