--- linux-2.4.21/net/bridge/br_private.h	Mon Feb 25 20:38:14 2002
+++ linux-2.4.21-ebt-brnf-3/net/bridge/br_private.h	Fri Aug  8 01:09:06 2003
@@ -144,8 +144,10 @@ extern void br_fdb_insert(struct net_bri
 /* br_forward.c */
 extern void br_deliver(struct net_bridge_port *to,
 		struct sk_buff *skb);
+extern int br_dev_queue_push_xmit(struct sk_buff *skb);
 extern void br_forward(struct net_bridge_port *to,
 		struct sk_buff *skb);
+extern int br_forward_finish(struct sk_buff *skb);
 extern void br_flood_deliver(struct net_bridge *br,
 		      struct sk_buff *skb,
 		      int clone);
@@ -166,7 +168,8 @@ extern void br_get_port_ifindices(struct
 			   int *ifindices);
 
 /* br_input.c */
-extern void br_handle_frame(struct sk_buff *skb);
+extern int br_handle_frame_finish(struct sk_buff *skb);
+extern int br_handle_frame(struct sk_buff *skb);
 
 /* br_ioctl.c */
 extern void br_call_ioctl_atomic(void (*fn)(void));
@@ -176,6 +179,10 @@ extern int br_ioctl(struct net_bridge *b
 	     unsigned long arg1,
 	     unsigned long arg2);
 extern int br_ioctl_deviceless_stub(unsigned long arg);
+
+/* br_netfilter.c */
+extern int br_netfilter_init(void);
+extern void br_netfilter_fini(void);
 
 /* br_stp.c */
 extern int br_is_root_bridge(struct net_bridge *br);
--- linux-2.4.21/include/linux/if_bridge.h	Thu Nov 22 20:47:12 2001
+++ linux-2.4.21-ebt-brnf-3/include/linux/if_bridge.h	Fri Aug  8 01:09:06 2003
@@ -102,7 +102,8 @@ struct net_bridge;
 struct net_bridge_port;
 
 extern int (*br_ioctl_hook)(unsigned long arg);
-extern void (*br_handle_frame_hook)(struct sk_buff *skb);
+extern int (*br_handle_frame_hook)(struct sk_buff *skb);
+extern int (*br_should_route_hook)(struct sk_buff **pskb);
 
 #endif
 
--- linux-2.4.21/net/core/dev.c	Fri Jun 13 16:51:39 2003
+++ linux-2.4.21-ebt-brnf-3/net/core/dev.c	Fri Aug  8 01:10:03 2003
@@ -1424,7 +1424,7 @@ static void net_tx_action(struct softirq
 
 
 #if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
-void (*br_handle_frame_hook)(struct sk_buff *skb) = NULL;
+int (*br_handle_frame_hook)(struct sk_buff *skb) = NULL;
 #endif
 
 static __inline__ int handle_bridge(struct sk_buff *skb,
@@ -1441,7 +1441,6 @@ static __inline__ int handle_bridge(stru
 		}
 	}
 
-	br_handle_frame_hook(skb);
 	return ret;
 }
 
@@ -1497,11 +1496,16 @@ int netif_receive_skb(struct sk_buff *sk
 	if (skb->dev->divert && skb->dev->divert->divert)
 		ret = handle_diverter(skb);
 #endif /* CONFIG_NET_DIVERT */
-			
+
 #if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
 	if (skb->dev->br_port != NULL &&
-	    br_handle_frame_hook != NULL) {
-		return handle_bridge(skb, pt_prev);
+        br_handle_frame_hook != NULL) {
+		int ret;
+
+		ret = handle_bridge(skb, pt_prev);
+		if (br_handle_frame_hook(skb) == 0)
+			return ret;
+		pt_prev = NULL;
 	}
 #endif
 
@@ -1897,7 +1901,7 @@ static int dev_proc_stats(char *buffer, 
  *	are adjusted, %RTM_NEWLINK is sent to the routing socket and the
  *	function returns zero.
  */
- 
+
 int netdev_set_master(struct net_device *slave, struct net_device *master)
 {
 	struct net_device *old = slave->master;
--- linux-2.4.21/net/bridge/br_input.c	Sat Aug  3 02:39:46 2002
+++ linux-2.4.21-ebt-brnf-3/net/bridge/br_input.c	Fri Aug  8 01:09:06 2003
@@ -24,6 +24,9 @@ unsigned char bridge_ula[6] = { 0x01, 0x
 
 static int br_pass_frame_up_finish(struct sk_buff *skb)
 {
+#ifdef CONFIG_NETFILTER_DEBUG
+	skb->nf_debug = 0;
+#endif
 	netif_rx(skb);
 
 	return 0;
@@ -46,7 +49,7 @@ static void br_pass_frame_up(struct net_
 			br_pass_frame_up_finish);
 }
 
-static int br_handle_frame_finish(struct sk_buff *skb)
+int br_handle_frame_finish(struct sk_buff *skb)
 {
 	struct net_bridge *br;
 	unsigned char *dest;
@@ -112,7 +115,7 @@ err_nolock:
 	return 0;
 }
 
-void br_handle_frame(struct sk_buff *skb)
+int br_handle_frame(struct sk_buff *skb)
 {
 	struct net_bridge *br;
 	unsigned char *dest;
@@ -146,25 +149,35 @@ void br_handle_frame(struct sk_buff *skb
 		goto handle_special_frame;
 
 	if (p->state == BR_STATE_FORWARDING) {
+
+		if (br_should_route_hook && br_should_route_hook(&skb)) {
+			read_unlock(&br->lock);
+			return -1;
+		}
+
+		if (!memcmp(p->br->dev.dev_addr, dest, ETH_ALEN))
+			skb->pkt_type = PACKET_HOST;
+
 		NF_HOOK(PF_BRIDGE, NF_BR_PRE_ROUTING, skb, skb->dev, NULL,
 			br_handle_frame_finish);
 		read_unlock(&br->lock);
-		return;
+		return 0;
 	}
 
 err:
 	read_unlock(&br->lock);
 err_nolock:
 	kfree_skb(skb);
-	return;
+	return 0;
 
 handle_special_frame:
 	if (!dest[5]) {
 		br_stp_handle_bpdu(skb);
 		read_unlock(&br->lock);
-		return;
+		return 0;
 	}
 
 	read_unlock(&br->lock);
 	kfree_skb(skb);
+	return 0;
 }
--- linux-2.4.21/net/bridge/br_forward.c	Sat Aug  3 02:39:46 2002
+++ linux-2.4.21-ebt-brnf-3/net/bridge/br_forward.c	Fri Aug  8 01:09:06 2003
@@ -30,18 +30,22 @@ static inline int should_deliver(struct 
 	return 1;
 }
 
-static int __dev_queue_push_xmit(struct sk_buff *skb)
+int br_dev_queue_push_xmit(struct sk_buff *skb)
 {
+#ifdef CONFIG_NETFILTER
+	if (skb->nf_bridge)
+		memcpy(skb->data - 16, skb->nf_bridge->hh, 16);
+#endif
 	skb_push(skb, ETH_HLEN);
 	dev_queue_xmit(skb);
 
 	return 0;
 }
 
-static int __br_forward_finish(struct sk_buff *skb)
+int br_forward_finish(struct sk_buff *skb)
 {
 	NF_HOOK(PF_BRIDGE, NF_BR_POST_ROUTING, skb, NULL, skb->dev,
-			__dev_queue_push_xmit);
+			br_dev_queue_push_xmit);
 
 	return 0;
 }
@@ -49,8 +53,11 @@ static int __br_forward_finish(struct sk
 static void __br_deliver(struct net_bridge_port *to, struct sk_buff *skb)
 {
 	skb->dev = to->dev;
+#ifdef CONFIG_NETFILTER_DEBUG
+	skb->nf_debug = 0;
+#endif
 	NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
-			__br_forward_finish);
+			br_forward_finish);
 }
 
 static void __br_forward(struct net_bridge_port *to, struct sk_buff *skb)
@@ -61,7 +68,7 @@ static void __br_forward(struct net_brid
 	skb->dev = to->dev;
 
 	NF_HOOK(PF_BRIDGE, NF_BR_FORWARD, skb, indev, skb->dev,
-			__br_forward_finish);
+			br_forward_finish);
 }
 
 /* called under bridge lock */
--- linux-2.4.21/net/bridge/br.c	Fri Nov 29 00:53:15 2002
+++ linux-2.4.21-ebt-brnf-3/net/bridge/br.c	Fri Aug  8 01:09:06 2003
@@ -29,6 +29,8 @@
 #include "../atm/lec.h"
 #endif
 
+int (*br_should_route_hook) (struct sk_buff **pskb) = NULL;
+
 void br_dec_use_count()
 {
 	MOD_DEC_USE_COUNT;
@@ -43,6 +45,10 @@ static int __init br_init(void)
 {
 	printk(KERN_INFO "NET4: Ethernet Bridge 008 for NET4.0\n");
 
+#ifdef CONFIG_NETFILTER
+	if (br_netfilter_init())
+		return 1;
+#endif
 	br_handle_frame_hook = br_handle_frame;
 	br_ioctl_hook = br_ioctl_deviceless_stub;
 #if defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE)
@@ -61,6 +67,9 @@ static void __br_clear_ioctl_hook(void)
 
 static void __exit br_deinit(void)
 {
+#ifdef CONFIG_NETFILTER
+	br_netfilter_fini();
+#endif
 	unregister_netdevice_notifier(&br_device_notifier);
 	br_call_ioctl_atomic(__br_clear_ioctl_hook);
 
@@ -74,7 +83,7 @@ static void __exit br_deinit(void)
 #endif
 }
 
-EXPORT_NO_SYMBOLS;
+EXPORT_SYMBOL(br_should_route_hook);
 
 module_init(br_init)
 module_exit(br_deinit)
--- linux-2.4.21/net/bridge/Makefile	Fri Dec 29 23:07:24 2000
+++ linux-2.4.21-ebt-brnf-3/net/bridge/Makefile	Fri Aug  8 01:09:06 2003
@@ -7,10 +7,17 @@
 #
 # Note 2! The CFLAGS definition is now in the main makefile...
 
+export-objs := br.o
+
 O_TARGET	:= bridge.o
 obj-y		:= br.o br_device.o br_fdb.o br_forward.o br_if.o br_input.o \
 			br_ioctl.o br_notify.o br_stp.o br_stp_bpdu.o \
 			br_stp_if.o br_stp_timer.o
+
+ifeq ($(CONFIG_NETFILTER),y)
+obj-y		+= br_netfilter.o
+endif
+
 obj-m		:= $(O_TARGET)
 
 include $(TOPDIR)/Rules.make
--- linux-2.4.21/include/linux/netfilter_bridge.h	Tue Jun 12 04:15:27 2001
+++ linux-2.4.21-ebt-brnf-3/include/linux/netfilter_bridge.h	Fri Aug  8 01:09:06 2003
@@ -1,11 +1,14 @@
 #ifndef __LINUX_BRIDGE_NETFILTER_H
 #define __LINUX_BRIDGE_NETFILTER_H
 
-/* bridge-specific defines for netfilter. 
+/* bridge-specific defines for netfilter.
  */
 
 #include <linux/config.h>
 #include <linux/netfilter.h>
+#if defined(__KERNEL__) && defined(CONFIG_NETFILTER)
+#include <asm/atomic.h>
+#endif
 
 /* Bridge Hooks */
 /* After promisc drops, checksum checks. */
@@ -18,7 +21,49 @@
 #define NF_BR_LOCAL_OUT		3
 /* Packets about to hit the wire. */
 #define NF_BR_POST_ROUTING	4
-#define NF_BR_NUMHOOKS		5
+/* Not really a hook, but used for the ebtables broute table */
+#define NF_BR_BROUTING		5
+#define NF_BR_NUMHOOKS		6
 
+#ifdef __KERNEL__
 
+#define BRNF_PKT_TYPE			0x01
+#define BRNF_BRIDGED_DNAT		0x02
+#define BRNF_DONT_TAKE_PARENT		0x04
+#define BRNF_BRIDGED			0x08
+
+enum nf_br_hook_priorities {
+	NF_BR_PRI_FIRST = INT_MIN,
+	NF_BR_PRI_NAT_DST_BRIDGED = -300,
+	NF_BR_PRI_FILTER_BRIDGED = -200,
+	NF_BR_PRI_BRNF = 0,
+	NF_BR_PRI_NAT_DST_OTHER = 100,
+	NF_BR_PRI_FILTER_OTHER = 200,
+	NF_BR_PRI_NAT_SRC = 300,
+	NF_BR_PRI_LAST = INT_MAX,
+};
+
+#ifdef CONFIG_NETFILTER
+static inline
+struct nf_bridge_info *nf_bridge_alloc(struct sk_buff *skb)
+{
+	struct nf_bridge_info **nf_bridge = &(skb->nf_bridge);
+
+	if ((*nf_bridge = kmalloc(sizeof(**nf_bridge), GFP_ATOMIC)) != NULL) {
+		atomic_set(&(*nf_bridge)->use, 1);
+		(*nf_bridge)->mask = 0;
+		(*nf_bridge)->physindev = (*nf_bridge)->physoutdev = NULL;
+	}
+
+	return *nf_bridge;
+}
+
+struct bridge_skb_cb {
+	union {
+		__u32 ipv4;
+	} daddr;
+};
+#endif /* CONFIG_NETFILTER */
+
+#endif /* __KERNEL__ */
 #endif
--- linux-2.4.21/net/Makefile	Sat Aug  3 02:39:46 2002
+++ linux-2.4.21-ebt-brnf-3/net/Makefile	Fri Aug  8 01:09:06 2003
@@ -7,7 +7,8 @@
 
 O_TARGET :=	network.o
 
-mod-subdirs :=	ipv4/netfilter ipv6/netfilter ipx irda bluetooth atm netlink sched core
+mod-subdirs :=	ipv4/netfilter ipv6/netfilter bridge/netfilter ipx irda \
+	bluetooth atm netlink sched core
 export-objs :=	netsyms.o
 
 subdir-y :=	core ethernet
@@ -23,6 +24,12 @@ subdir-$(CONFIG_IPV6)		+= ipv6
 ifneq ($(CONFIG_IPV6),n)
 ifneq ($(CONFIG_IPV6),)
 subdir-$(CONFIG_NETFILTER)	+= ipv6/netfilter
+endif
+endif
+
+ifneq ($(CONFIG_BRIDGE),n)
+ifneq ($(CONFIG_BRIDGE),)
+subdir-$(CONFIG_BRIDGE)		+= bridge/netfilter
 endif
 endif
 
--- linux-2.4.21/net/Config.in	Sat Aug  3 02:39:46 2002
+++ linux-2.4.21-ebt-brnf-3/net/Config.in	Fri Aug  8 01:09:06 2003
@@ -65,6 +65,9 @@ if [ "$CONFIG_DECNET" != "n" ]; then
    source net/decnet/Config.in
 fi
 dep_tristate '802.1d Ethernet Bridging' CONFIG_BRIDGE $CONFIG_INET
+if [ "$CONFIG_BRIDGE" != "n" -a "$CONFIG_NETFILTER" != "n" ]; then
+   source net/bridge/netfilter/Config.in
+fi
 if [ "$CONFIG_EXPERIMENTAL" = "y" ]; then
    tristate 'CCITT X.25 Packet Layer (EXPERIMENTAL)' CONFIG_X25
    tristate 'LAPB Data Link Driver (EXPERIMENTAL)' CONFIG_LAPB
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/net/bridge/netfilter/Makefile	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,30 @@
+#
+# Makefile for the netfilter modules on top of bridging.
+#
+# Note! Dependencies are done automagically by 'make dep', which also
+# removes any old dependencies. DON'T put your own dependencies here
+# unless it's something special (ie not a .c file).
+#
+# Note 2! The CFLAGS definition is now in the main makefile...
+
+O_TARGET	:= netfilter.o
+
+export-objs := ebtables.o
+
+obj-$(CONFIG_BRIDGE_NF_EBTABLES) += ebtables.o
+obj-$(CONFIG_BRIDGE_EBT_T_FILTER) += ebtable_filter.o
+obj-$(CONFIG_BRIDGE_EBT_T_NAT) += ebtable_nat.o
+obj-$(CONFIG_BRIDGE_EBT_BROUTE) += ebtable_broute.o
+obj-$(CONFIG_BRIDGE_EBT_IPF) += ebt_ip.o
+obj-$(CONFIG_BRIDGE_EBT_ARPF) += ebt_arp.o
+obj-$(CONFIG_BRIDGE_EBT_VLANF) += ebt_vlan.o
+obj-$(CONFIG_BRIDGE_EBT_MARKF) += ebt_mark_m.o
+obj-$(CONFIG_BRIDGE_EBT_802_3) += ebt_802_3.o
+obj-$(CONFIG_BRIDGE_EBT_PKTTYPE) += ebt_pkttype.o
+obj-$(CONFIG_BRIDGE_EBT_PKTTYPE) += ebt_stp.o
+obj-$(CONFIG_BRIDGE_EBT_LOG) += ebt_log.o
+obj-$(CONFIG_BRIDGE_EBT_SNAT) += ebt_snat.o
+obj-$(CONFIG_BRIDGE_EBT_DNAT) += ebt_dnat.o
+obj-$(CONFIG_BRIDGE_EBT_REDIRECT) += ebt_redirect.o
+obj-$(CONFIG_BRIDGE_EBT_MARK_T) += ebt_mark.o
+include $(TOPDIR)/Rules.make
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/net/bridge/netfilter/Config.in	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,19 @@
+#
+# Bridge netfilter configuration
+#
+dep_tristate '  Bridge: ebtables' CONFIG_BRIDGE_NF_EBTABLES $CONFIG_BRIDGE
+dep_tristate '    ebt: filter table support' CONFIG_BRIDGE_EBT_T_FILTER $CONFIG_BRIDGE_NF_EBTABLES
+dep_tristate '    ebt: nat table support' CONFIG_BRIDGE_EBT_T_NAT $CONFIG_BRIDGE_NF_EBTABLES
+dep_tristate '    ebt: broute table support' CONFIG_BRIDGE_EBT_BROUTE $CONFIG_BRIDGE_NF_EBTABLES
+dep_tristate '    ebt: log support' CONFIG_BRIDGE_EBT_LOG $CONFIG_BRIDGE_NF_EBTABLES
+dep_tristate '    ebt: IP filter support' CONFIG_BRIDGE_EBT_IPF $CONFIG_BRIDGE_NF_EBTABLES
+dep_tristate '    ebt: ARP filter support' CONFIG_BRIDGE_EBT_ARPF $CONFIG_BRIDGE_NF_EBTABLES
+dep_tristate '    ebt: 802.1Q VLAN filter support' CONFIG_BRIDGE_EBT_VLANF $CONFIG_BRIDGE_NF_EBTABLES
+dep_tristate '    ebt: 802.3 filter support' CONFIG_BRIDGE_EBT_802_3 $CONFIG_BRIDGE_NF_EBTABLES
+dep_tristate '    ebt: packet type filter support' CONFIG_BRIDGE_EBT_PKTTYPE $CONFIG_BRIDGE_NF_EBTABLES
+dep_tristate '    ebt: STP filter support' CONFIG_BRIDGE_EBT_STP $CONFIG_BRIDGE_NF_EBTABLES
+dep_tristate '    ebt: mark filter support' CONFIG_BRIDGE_EBT_MARKF $CONFIG_BRIDGE_NF_EBTABLES
+dep_tristate '    ebt: snat target support' CONFIG_BRIDGE_EBT_SNAT $CONFIG_BRIDGE_NF_EBTABLES
+dep_tristate '    ebt: dnat target support' CONFIG_BRIDGE_EBT_DNAT $CONFIG_BRIDGE_NF_EBTABLES
+dep_tristate '    ebt: redirect target support' CONFIG_BRIDGE_EBT_REDIRECT $CONFIG_BRIDGE_NF_EBTABLES
+dep_tristate '    ebt: mark target support' CONFIG_BRIDGE_EBT_MARK_T $CONFIG_BRIDGE_NF_EBTABLES
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/net/bridge/netfilter/ebtable_filter.c	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,90 @@
+/*
+ *  ebtable_filter
+ *
+ *	Authors:
+ *	Bart De Schuymer <bart.de.schuymer@pandora.be>
+ *
+ *  April, 2002
+ *
+ */
+
+#include <linux/netfilter_bridge/ebtables.h>
+#include <linux/module.h>
+
+#define FILTER_VALID_HOOKS ((1 << NF_BR_LOCAL_IN) | (1 << NF_BR_FORWARD) | \
+   (1 << NF_BR_LOCAL_OUT))
+
+static struct ebt_entries initial_chains[] =
+{
+  {0, "INPUT", 0, EBT_ACCEPT, 0},
+  {0, "FORWARD", 0, EBT_ACCEPT, 0},
+  {0, "OUTPUT", 0, EBT_ACCEPT, 0}
+};
+
+static struct ebt_replace initial_table =
+{
+  "filter", FILTER_VALID_HOOKS, 0, 3 * sizeof(struct ebt_entries),
+  { [NF_BR_LOCAL_IN]&initial_chains[0], [NF_BR_FORWARD]&initial_chains[1],
+    [NF_BR_LOCAL_OUT]&initial_chains[2] }, 0, NULL, (char *)initial_chains
+};
+
+static int check(const struct ebt_table_info *info, unsigned int valid_hooks)
+{
+	if (valid_hooks & ~FILTER_VALID_HOOKS)
+		return -EINVAL;
+	return 0;
+}
+
+static struct ebt_table frame_filter =
+{ 
+  {NULL, NULL}, "filter", &initial_table, FILTER_VALID_HOOKS, 
+  RW_LOCK_UNLOCKED, check, NULL
+};
+
+static unsigned int
+ebt_hook (unsigned int hook, struct sk_buff **pskb, const struct net_device *in,
+   const struct net_device *out, int (*okfn)(struct sk_buff *))
+{
+	return ebt_do_table(hook, pskb, in, out, &frame_filter);
+}
+
+static struct nf_hook_ops ebt_ops_filter[] = {
+	{ { NULL, NULL }, ebt_hook, PF_BRIDGE, NF_BR_LOCAL_IN,
+	   NF_BR_PRI_FILTER_BRIDGED},
+	{ { NULL, NULL }, ebt_hook, PF_BRIDGE, NF_BR_FORWARD,
+	   NF_BR_PRI_FILTER_BRIDGED},
+	{ { NULL, NULL }, ebt_hook, PF_BRIDGE, NF_BR_LOCAL_OUT,
+	   NF_BR_PRI_FILTER_OTHER}
+};
+
+static int __init init(void)
+{
+	int i, j, ret;
+
+	ret = ebt_register_table(&frame_filter);
+	if (ret < 0)
+		return ret;
+	for (i = 0; i < sizeof(ebt_ops_filter) / sizeof(ebt_ops_filter[0]); i++)
+		if ((ret = nf_register_hook(&ebt_ops_filter[i])) < 0)
+			goto cleanup;
+	return ret;
+cleanup:
+	for (j = 0; j < i; j++)
+		nf_unregister_hook(&ebt_ops_filter[j]);
+	ebt_unregister_table(&frame_filter);
+	return ret;
+}
+
+static void __exit fini(void)
+{
+	int i;
+
+	for (i = 0; i < sizeof(ebt_ops_filter) / sizeof(ebt_ops_filter[0]); i++)
+		nf_unregister_hook(&ebt_ops_filter[i]);
+	ebt_unregister_table(&frame_filter);
+}
+
+module_init(init);
+module_exit(fini);
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/net/bridge/netfilter/ebtable_nat.c	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,96 @@
+/*
+ *  ebtable_nat
+ *
+ *	Authors:
+ *	Bart De Schuymer <bart.de.schuymer@pandora.be>
+ *
+ *  April, 2002
+ *
+ */
+
+#include <linux/netfilter_bridge/ebtables.h>
+#include <linux/module.h>
+#define NAT_VALID_HOOKS ((1 << NF_BR_PRE_ROUTING) | (1 << NF_BR_LOCAL_OUT) | \
+   (1 << NF_BR_POST_ROUTING))
+
+static struct ebt_entries initial_chains[] =
+{
+  {0, "PREROUTING", 0, EBT_ACCEPT, 0},
+  {0, "OUTPUT", 0, EBT_ACCEPT, 0},
+  {0, "POSTROUTING", 0, EBT_ACCEPT, 0}
+};
+
+static struct ebt_replace initial_table =
+{
+  "nat", NAT_VALID_HOOKS, 0, 3 * sizeof(struct ebt_entries),
+  { [NF_BR_PRE_ROUTING]&initial_chains[0], [NF_BR_LOCAL_OUT]&initial_chains[1],
+    [NF_BR_POST_ROUTING]&initial_chains[2] }, 0, NULL, (char *)initial_chains
+};
+
+static int check(const struct ebt_table_info *info, unsigned int valid_hooks)
+{
+	if (valid_hooks & ~NAT_VALID_HOOKS)
+		return -EINVAL;
+	return 0;
+}
+
+static struct ebt_table frame_nat =
+{
+  {NULL, NULL}, "nat", &initial_table, NAT_VALID_HOOKS,
+  RW_LOCK_UNLOCKED, check, NULL
+};
+
+static unsigned int
+ebt_nat_dst(unsigned int hook, struct sk_buff **pskb, const struct net_device *in
+   , const struct net_device *out, int (*okfn)(struct sk_buff *))
+{
+	return ebt_do_table(hook, pskb, in, out, &frame_nat);
+}
+
+static unsigned int
+ebt_nat_src(unsigned int hook, struct sk_buff **pskb, const struct net_device *in
+   , const struct net_device *out, int (*okfn)(struct sk_buff *))
+{
+	return ebt_do_table(hook, pskb, in, out, &frame_nat);
+}
+
+static struct nf_hook_ops ebt_ops_nat[] = {
+	{ { NULL, NULL }, ebt_nat_dst, PF_BRIDGE, NF_BR_LOCAL_OUT,
+	   NF_BR_PRI_NAT_DST_OTHER},
+	{ { NULL, NULL }, ebt_nat_src, PF_BRIDGE, NF_BR_POST_ROUTING,
+	   NF_BR_PRI_NAT_SRC},
+	{ { NULL, NULL }, ebt_nat_dst, PF_BRIDGE, NF_BR_PRE_ROUTING,
+	   NF_BR_PRI_NAT_DST_BRIDGED},
+};
+
+static int __init init(void)
+{
+	int i, ret, j;
+
+	ret = ebt_register_table(&frame_nat);
+	if (ret < 0)
+		return ret;
+	for (i = 0; i < sizeof(ebt_ops_nat) / sizeof(ebt_ops_nat[0]); i++)
+		if ((ret = nf_register_hook(&ebt_ops_nat[i])) < 0)
+			goto cleanup;
+	return ret;
+cleanup:
+	for (j = 0; j < i; j++)
+		nf_unregister_hook(&ebt_ops_nat[j]);
+	ebt_unregister_table(&frame_nat);
+	return ret;
+}
+
+static void __exit fini(void)
+{
+	int i;
+
+	for (i = 0; i < sizeof(ebt_ops_nat) / sizeof(ebt_ops_nat[0]); i++)
+		nf_unregister_hook(&ebt_ops_nat[i]);
+	ebt_unregister_table(&frame_nat);
+}
+
+module_init(init);
+module_exit(fini);
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/net/bridge/netfilter/ebtable_broute.c	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,79 @@
+/*
+ *  ebtable_broute
+ *
+ *	Authors:
+ *	Bart De Schuymer <bart.de.schuymer@pandora.be>
+ *
+ *  April, 2002
+ *
+ *  This table lets you choose between routing and bridging for frames
+ *  entering on a bridge enslaved nic. This table is traversed before any
+ *  other ebtables table. See net/bridge/br_input.c.
+ */
+
+#include <linux/netfilter_bridge/ebtables.h>
+#include <linux/module.h>
+#include <linux/if_bridge.h>
+#include <linux/brlock.h>
+
+// EBT_ACCEPT means the frame will be bridged
+// EBT_DROP means the frame will be routed
+static struct ebt_entries initial_chain =
+  {0, "BROUTING", 0, EBT_ACCEPT, 0};
+
+static struct ebt_replace initial_table =
+{
+  "broute", 1 << NF_BR_BROUTING, 0, sizeof(struct ebt_entries),
+  { [NF_BR_BROUTING]&initial_chain}, 0, NULL, (char *)&initial_chain
+};
+
+static int check(const struct ebt_table_info *info, unsigned int valid_hooks)
+{
+	if (valid_hooks & ~(1 << NF_BR_BROUTING))
+		return -EINVAL;
+	return 0;
+}
+
+static struct ebt_table broute_table =
+{
+  {NULL, NULL}, "broute", &initial_table, 1 << NF_BR_BROUTING,
+  RW_LOCK_UNLOCKED, check, NULL
+};
+
+static int ebt_broute(struct sk_buff **pskb)
+{
+	int ret;
+
+	ret = ebt_do_table(NF_BR_BROUTING, pskb, (*pskb)->dev, NULL,
+	   &broute_table);
+	if (ret == NF_DROP)
+		return 1; // route it
+	return 0; // bridge it
+}
+
+static int __init init(void)
+{
+	int ret;
+
+	ret = ebt_register_table(&broute_table);
+	if (ret < 0)
+		return ret;
+	br_write_lock_bh(BR_NETPROTO_LOCK);
+	// see br_input.c
+	br_should_route_hook = ebt_broute;
+	br_write_unlock_bh(BR_NETPROTO_LOCK);
+	return ret;
+}
+
+static void __exit fini(void)
+{
+	br_write_lock_bh(BR_NETPROTO_LOCK);
+	br_should_route_hook = NULL;
+	br_write_unlock_bh(BR_NETPROTO_LOCK);
+	ebt_unregister_table(&broute_table);
+}
+
+module_init(init);
+module_exit(fini);
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/net/bridge/netfilter/ebt_802_3.c	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,74 @@
+/*
+ * 802_3
+ *
+ * Author:
+ * Chris Vitale csv@bluetail.com
+ *
+ * May 2003
+ * 
+ */
+
+#include <linux/netfilter_bridge/ebtables.h>
+#include <linux/netfilter_bridge/ebt_802_3.h>
+#include <linux/module.h>
+
+static int ebt_filter_802_3(const struct sk_buff *skb, const struct net_device *in,
+   const struct net_device *out, const void *data, unsigned int datalen)
+{
+	struct ebt_802_3_info *info = (struct ebt_802_3_info *)data;
+	struct ebt_802_3_hdr *hdr = (struct ebt_802_3_hdr *)skb->mac.ethernet;
+	uint16_t type = hdr->llc.ui.ctrl & IS_UI ? hdr->llc.ui.type : hdr->llc.ni.type;
+
+	if (info->bitmask & EBT_802_3_SAP) {
+		if (FWINV(info->sap != hdr->llc.ui.ssap, EBT_802_3_SAP)) 
+				return EBT_NOMATCH;
+		if (FWINV(info->sap != hdr->llc.ui.dsap, EBT_802_3_SAP))
+				return EBT_NOMATCH;
+	}
+
+	if (info->bitmask & EBT_802_3_TYPE) {
+		if (!(hdr->llc.ui.dsap == CHECK_TYPE && hdr->llc.ui.ssap == CHECK_TYPE))
+			return EBT_NOMATCH;
+		if (FWINV(info->type != type, EBT_802_3_TYPE)) 
+			return EBT_NOMATCH;
+	}
+
+	return EBT_MATCH;
+}
+
+static struct ebt_match filter_802_3;
+static int ebt_802_3_check(const char *tablename, unsigned int hookmask,
+   const struct ebt_entry *e, void *data, unsigned int datalen)
+{
+	struct ebt_802_3_info *info = (struct ebt_802_3_info *)data;
+
+	if (datalen != EBT_ALIGN(sizeof(struct ebt_802_3_info)))
+		return -EINVAL;
+	if (info->bitmask & ~EBT_802_3_MASK || info->invflags & ~EBT_802_3_MASK)
+		return -EINVAL;
+
+	return 0;
+}
+
+static struct ebt_match filter_802_3 =
+{
+	.name		= EBT_802_3_MATCH,
+	.match		= ebt_filter_802_3,
+	.check		= ebt_802_3_check,
+	.me		= THIS_MODULE,
+};
+
+static int __init init(void)
+{
+	return ebt_register_match(&filter_802_3);
+}
+
+static void __exit fini(void)
+{
+	ebt_unregister_match(&filter_802_3);
+}
+
+module_init(init);
+module_exit(fini);
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/net/bridge/netfilter/ebt_mark.c	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,66 @@
+/*
+ *  ebt_mark
+ *
+ *	Authors:
+ *	Bart De Schuymer <bart.de.schuymer@pandora.be>
+ *
+ *  July, 2002
+ *
+ */
+
+// The mark target can be used in any chain
+// I believe adding a mangle table just for marking is total overkill
+// Marking a frame doesn't really change anything in the frame anyway
+
+#include <linux/netfilter_bridge/ebtables.h>
+#include <linux/netfilter_bridge/ebt_mark_t.h>
+#include <linux/module.h>
+
+static int ebt_target_mark(struct sk_buff **pskb, unsigned int hooknr,
+   const struct net_device *in, const struct net_device *out,
+   const void *data, unsigned int datalen)
+{
+	struct ebt_mark_t_info *info = (struct ebt_mark_t_info *)data;
+
+	if ((*pskb)->nfmark != info->mark) {
+		(*pskb)->nfmark = info->mark;
+		(*pskb)->nfcache |= NFC_ALTERED;
+	}
+	return info->target;
+}
+
+static int ebt_target_mark_check(const char *tablename, unsigned int hookmask,
+   const struct ebt_entry *e, void *data, unsigned int datalen)
+{
+	struct ebt_mark_t_info *info = (struct ebt_mark_t_info *)data;
+
+	if (datalen != EBT_ALIGN(sizeof(struct ebt_mark_t_info)))
+		return -EINVAL;
+	if (BASE_CHAIN && info->target == EBT_RETURN)
+		return -EINVAL;
+	CLEAR_BASE_CHAIN_BIT;
+	if (INVALID_TARGET)
+		return -EINVAL;
+	return 0;
+}
+
+static struct ebt_target mark_target =
+{
+	{NULL, NULL}, EBT_MARK_TARGET, ebt_target_mark,
+	ebt_target_mark_check, NULL, THIS_MODULE
+};
+
+static int __init init(void)
+{
+	return ebt_register_target(&mark_target);
+}
+
+static void __exit fini(void)
+{
+	ebt_unregister_target(&mark_target);
+}
+
+module_init(init);
+module_exit(fini);
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/net/bridge/netfilter/ebt_mark_m.c	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,61 @@
+/*
+ *  ebt_mark_m
+ *
+ *	Authors:
+ *	Bart De Schuymer <bart.de.schuymer@pandora.be>
+ *
+ *  July, 2002
+ *
+ */
+
+#include <linux/netfilter_bridge/ebtables.h>
+#include <linux/netfilter_bridge/ebt_mark_m.h>
+#include <linux/module.h>
+
+static int ebt_filter_mark(const struct sk_buff *skb,
+   const struct net_device *in, const struct net_device *out, const void *data,
+   unsigned int datalen)
+{
+	struct ebt_mark_m_info *info = (struct ebt_mark_m_info *) data;
+
+	if (info->bitmask & EBT_MARK_OR)
+		return !(!!(skb->nfmark & info->mask) ^ info->invert);
+	return !(((skb->nfmark & info->mask) == info->mark) ^ info->invert);
+}
+
+static int ebt_mark_check(const char *tablename, unsigned int hookmask,
+   const struct ebt_entry *e, void *data, unsigned int datalen)
+{
+        struct ebt_mark_m_info *info = (struct ebt_mark_m_info *) data;
+
+	if (datalen != EBT_ALIGN(sizeof(struct ebt_mark_m_info)))
+		return -EINVAL;
+	if (info->bitmask & ~EBT_MARK_MASK)
+		return -EINVAL;
+	if ((info->bitmask & EBT_MARK_OR) && (info->bitmask & EBT_MARK_AND))
+		return -EINVAL;
+	if (!info->bitmask)
+		return -EINVAL;
+	return 0;
+}
+
+static struct ebt_match filter_mark =
+{
+	{NULL, NULL}, EBT_MARK_MATCH, ebt_filter_mark, ebt_mark_check, NULL,
+	THIS_MODULE
+};
+
+static int __init init(void)
+{
+	return ebt_register_match(&filter_mark);
+}
+
+static void __exit fini(void)
+{
+	ebt_unregister_match(&filter_mark);
+}
+
+module_init(init);
+module_exit(fini);
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/net/bridge/netfilter/ebt_pkttype.c	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,60 @@
+/*
+ *  ebt_pkttype
+ *
+ *	Authors:
+ *	Bart De Schuymer <bdschuym@pandora.be>
+ *
+ *  April, 2003
+ *
+ */
+
+#include <linux/netfilter_bridge/ebtables.h>
+#include <linux/netfilter_bridge/ebt_pkttype.h>
+#include <linux/module.h>
+
+static int ebt_filter_pkttype(const struct sk_buff *skb,
+   const struct net_device *in,
+   const struct net_device *out,
+   const void *data,
+   unsigned int datalen)
+{
+	struct ebt_pkttype_info *info = (struct ebt_pkttype_info *)data;
+
+	return (skb->pkt_type != info->pkt_type) ^ info->invert;
+}
+
+static int ebt_pkttype_check(const char *tablename, unsigned int hookmask,
+   const struct ebt_entry *e, void *data, unsigned int datalen)
+{
+	struct ebt_pkttype_info *info = (struct ebt_pkttype_info *)data;
+
+	if (datalen != EBT_ALIGN(sizeof(struct ebt_pkttype_info)))
+		return -EINVAL;
+	if (info->invert != 0 && info->invert != 1)
+		return -EINVAL;
+	/* Allow any pkt_type value */
+	return 0;
+}
+
+static struct ebt_match filter_pkttype =
+{
+	.name		= EBT_PKTTYPE_MATCH,
+	.match		= ebt_filter_pkttype,
+	.check		= ebt_pkttype_check,
+	.me		= THIS_MODULE,
+};
+
+static int __init init(void)
+{
+	return ebt_register_match(&filter_pkttype);
+}
+
+static void __exit fini(void)
+{
+	ebt_unregister_match(&filter_pkttype);
+}
+
+module_init(init);
+module_exit(fini);
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/net/bridge/netfilter/ebt_stp.c	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,191 @@
+/*
+ *  ebt_stp
+ *
+ *	Authors:
+ *	Bart De Schuymer <bdschuym@pandora.be>
+ *	Stephen Hemminger <shemminger@osdl.org>
+ *
+ *  June, 2003
+ */
+
+#include <linux/netfilter_bridge/ebtables.h>
+#include <linux/netfilter_bridge/ebt_stp.h>
+#include <linux/module.h>
+
+#define BPDU_TYPE_CONFIG 0
+#define BPDU_TYPE_TCN 0x80
+
+struct stp_header {
+	uint8_t dsap;
+	uint8_t ssap;
+	uint8_t ctrl;
+	uint8_t pid;
+	uint8_t vers;
+	uint8_t type;
+};
+
+struct stp_config_pdu {
+	uint8_t flags;
+	uint8_t root[8];
+	uint8_t root_cost[4];
+	uint8_t sender[8];
+	uint8_t port[2];
+	uint8_t msg_age[2];
+	uint8_t max_age[2];
+	uint8_t hello_time[2];
+	uint8_t forward_delay[2];
+};
+
+#define NR16(p) (p[0] << 8 | p[1])
+#define NR32(p) ((p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3])
+
+static int ebt_filter_config(struct ebt_stp_info *info,
+   struct stp_config_pdu *stpc)
+{
+	struct ebt_stp_config_info *c;
+	uint16_t v16;
+	uint32_t v32;
+	int verdict, i;
+
+	c = &info->config;
+	if ((info->bitmask & EBT_STP_FLAGS) &&
+	    FWINV(c->flags != stpc->flags, EBT_STP_FLAGS))
+		return EBT_NOMATCH;
+	if (info->bitmask & EBT_STP_ROOTPRIO) {
+		v16 = NR16(stpc->root);
+		if (FWINV(v16 < c->root_priol ||
+		    v16 > c->root_priou, EBT_STP_ROOTPRIO))
+			return EBT_NOMATCH;
+	}
+	if (info->bitmask & EBT_STP_ROOTADDR) {
+		verdict = 0;
+		for (i = 0; i < 6; i++)
+			verdict |= (stpc->root[2+i] ^ c->root_addr[i]) &
+			           c->root_addrmsk[i];
+		if (FWINV(verdict != 0, EBT_STP_ROOTADDR))
+			return EBT_NOMATCH;
+	}
+	if (info->bitmask & EBT_STP_ROOTCOST) {
+		v32 = NR32(stpc->root_cost);
+		if (FWINV(v32 < c->root_costl ||
+		    v32 > c->root_costu, EBT_STP_ROOTCOST))
+			return EBT_NOMATCH;
+	}
+	if (info->bitmask & EBT_STP_SENDERPRIO) {
+		v16 = NR16(stpc->sender);
+		if (FWINV(v16 < c->sender_priol ||
+		    v16 > c->sender_priou, EBT_STP_SENDERPRIO))
+			return EBT_NOMATCH;
+	}
+	if (info->bitmask & EBT_STP_SENDERADDR) {
+		verdict = 0;
+		for (i = 0; i < 6; i++)
+			verdict |= (stpc->sender[2+i] ^ c->sender_addr[i]) &
+			           c->sender_addrmsk[i];
+		if (FWINV(verdict != 0, EBT_STP_SENDERADDR))
+			return EBT_NOMATCH;
+	}
+	if (info->bitmask & EBT_STP_PORT) {
+		v16 = NR16(stpc->port);
+		if (FWINV(v16 < c->portl ||
+		    v16 > c->portu, EBT_STP_PORT))
+			return EBT_NOMATCH;
+	}
+	if (info->bitmask & EBT_STP_MSGAGE) {
+		v16 = NR16(stpc->msg_age);
+		if (FWINV(v16 < c->msg_agel ||
+		    v16 > c->msg_ageu, EBT_STP_MSGAGE))
+			return EBT_NOMATCH;
+	}
+	if (info->bitmask & EBT_STP_MAXAGE) {
+		v16 = NR16(stpc->max_age);
+		if (FWINV(v16 < c->max_agel ||
+		    v16 > c->max_ageu, EBT_STP_MAXAGE))
+			return EBT_NOMATCH;
+	}
+	if (info->bitmask & EBT_STP_HELLOTIME) {
+		v16 = NR16(stpc->hello_time);
+		if (FWINV(v16 < c->hello_timel ||
+		    v16 > c->hello_timeu, EBT_STP_HELLOTIME))
+			return EBT_NOMATCH;
+	}
+	if (info->bitmask & EBT_STP_FWDD) {
+		v16 = NR16(stpc->forward_delay);
+		if (FWINV(v16 < c->forward_delayl ||
+		    v16 > c->forward_delayu, EBT_STP_FWDD))
+			return EBT_NOMATCH;
+	}
+	return EBT_MATCH;
+}
+
+static int ebt_filter_stp(const struct sk_buff *skb, const struct net_device *in,
+   const struct net_device *out, const void *data, unsigned int datalen)
+{
+	struct ebt_stp_info *info = (struct ebt_stp_info *)data;
+	struct stp_header stph;
+	uint8_t header[6] = {0x42, 0x42, 0x03, 0x00, 0x00, 0x00};
+	if (skb_copy_bits(skb, 0, &stph, sizeof(stph)))
+		return EBT_NOMATCH;
+
+	/* The stp code only considers these */
+	if (memcmp(&stph, header, sizeof(header)))
+		return EBT_NOMATCH;
+
+	if (info->bitmask & EBT_STP_TYPE
+	    && FWINV(info->type != stph.type, EBT_STP_TYPE))
+		return EBT_NOMATCH;
+
+	if (stph.type == BPDU_TYPE_CONFIG &&
+	    info->bitmask & EBT_STP_CONFIG_MASK) {
+		struct stp_config_pdu stpc;
+
+		if (skb_copy_bits(skb, sizeof(stph), &stpc, sizeof(stpc)))
+		    return EBT_NOMATCH;
+		return ebt_filter_config(info, &stpc);
+	}
+	return EBT_MATCH;
+}
+
+static int ebt_stp_check(const char *tablename, unsigned int hookmask,
+   const struct ebt_entry *e, void *data, unsigned int datalen)
+{
+	struct ebt_stp_info *info = (struct ebt_stp_info *)data;
+	int len = EBT_ALIGN(sizeof(struct ebt_stp_info));
+	uint8_t bridge_ula[6] = { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 };
+	uint8_t msk[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
+
+	if (info->bitmask & ~EBT_STP_MASK || info->invflags & ~EBT_STP_MASK ||
+	    !(info->bitmask & EBT_STP_MASK))
+		return -EINVAL;
+	if (datalen != len)
+		return -EINVAL;
+	/* Make sure the match only receives stp frames */
+	if (memcmp(e->destmac, bridge_ula, ETH_ALEN) ||
+	    memcmp(e->destmsk, msk, ETH_ALEN) || !(e->bitmask & EBT_DESTMAC))
+		return -EINVAL;
+
+	return 0;
+}
+
+static struct ebt_match filter_stp =
+{
+	.name		= EBT_STP_MATCH,
+	.match		= ebt_filter_stp,
+	.check		= ebt_stp_check,
+	.me		= THIS_MODULE,
+};
+
+static int __init init(void)
+{
+	return ebt_register_match(&filter_stp);
+}
+
+static void __exit fini(void)
+{
+	ebt_unregister_match(&filter_stp);
+}
+
+module_init(init);
+module_exit(fini);
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/net/bridge/netfilter/ebt_redirect.c	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,71 @@
+/*
+ *  ebt_redirect
+ *
+ *	Authors:
+ *	Bart De Schuymer <bart.de.schuymer@pandora.be>
+ *
+ *  April, 2002
+ *
+ */
+
+#include <linux/netfilter_bridge/ebtables.h>
+#include <linux/netfilter_bridge/ebt_redirect.h>
+#include <linux/module.h>
+#include <net/sock.h>
+#include "../br_private.h"
+
+static int ebt_target_redirect(struct sk_buff **pskb, unsigned int hooknr,
+   const struct net_device *in, const struct net_device *out,
+   const void *data, unsigned int datalen)
+{
+	struct ebt_redirect_info *info = (struct ebt_redirect_info *)data;
+
+	if (hooknr != NF_BR_BROUTING)
+		memcpy((**pskb).mac.ethernet->h_dest,
+		   in->br_port->br->dev.dev_addr, ETH_ALEN);
+	else {
+		memcpy((**pskb).mac.ethernet->h_dest,
+		   in->dev_addr, ETH_ALEN);
+		(*pskb)->pkt_type = PACKET_HOST;
+	}
+	return info->target;
+}
+
+static int ebt_target_redirect_check(const char *tablename, unsigned int hookmask,
+   const struct ebt_entry *e, void *data, unsigned int datalen)
+{
+	struct ebt_redirect_info *info = (struct ebt_redirect_info *)data;
+
+	if (datalen != EBT_ALIGN(sizeof(struct ebt_redirect_info)))
+		return -EINVAL;
+	if (BASE_CHAIN && info->target == EBT_RETURN)
+		return -EINVAL;
+	CLEAR_BASE_CHAIN_BIT;
+	if ( (strcmp(tablename, "nat") || hookmask & ~(1 << NF_BR_PRE_ROUTING)) &&
+	     (strcmp(tablename, "broute") || hookmask & ~(1 << NF_BR_BROUTING)) )
+		return -EINVAL;
+	if (INVALID_TARGET)
+		return -EINVAL;
+	return 0;
+}
+
+static struct ebt_target redirect_target =
+{
+	{NULL, NULL}, EBT_REDIRECT_TARGET, ebt_target_redirect,
+	ebt_target_redirect_check, NULL, THIS_MODULE
+};
+
+static int __init init(void)
+{
+	return ebt_register_target(&redirect_target);
+}
+
+static void __exit fini(void)
+{
+	ebt_unregister_target(&redirect_target);
+}
+
+module_init(init);
+module_exit(fini);
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/net/bridge/netfilter/ebt_arp.c	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,149 @@
+/*
+ *  ebt_arp
+ *
+ *	Authors:
+ *	Bart De Schuymer <bart.de.schuymer@pandora.be>
+ *	Tim Gardner <timg@tpi.com>
+ *
+ *  April, 2002
+ *
+ */
+
+#include <linux/netfilter_bridge/ebtables.h>
+#include <linux/netfilter_bridge/ebt_arp.h>
+#include <linux/if_arp.h>
+#include <linux/if_ether.h>
+#include <linux/module.h>
+
+static int ebt_filter_arp(const struct sk_buff *skb, const struct net_device *in,
+   const struct net_device *out, const void *data, unsigned int datalen)
+{
+	struct ebt_arp_info *info = (struct ebt_arp_info *)data;
+
+	if (info->bitmask & EBT_ARP_OPCODE && FWINV(info->opcode !=
+	   ((*skb).nh.arph)->ar_op, EBT_ARP_OPCODE))
+		return EBT_NOMATCH;
+	if (info->bitmask & EBT_ARP_HTYPE && FWINV(info->htype !=
+	   ((*skb).nh.arph)->ar_hrd, EBT_ARP_HTYPE))
+		return EBT_NOMATCH;
+	if (info->bitmask & EBT_ARP_PTYPE && FWINV(info->ptype !=
+	   ((*skb).nh.arph)->ar_pro, EBT_ARP_PTYPE))
+		return EBT_NOMATCH;
+
+	if (info->bitmask & (EBT_ARP_SRC_IP | EBT_ARP_DST_IP))
+	{
+		uint32_t arp_len = sizeof(struct arphdr) +
+		   (2 * (((*skb).nh.arph)->ar_hln)) +
+		   (2 * (((*skb).nh.arph)->ar_pln));
+		uint32_t dst;
+		uint32_t src;
+
+		// Make sure the packet is long enough.
+		if ((((*skb).nh.raw) + arp_len) > (*skb).tail)
+			return EBT_NOMATCH;
+		// IPv4 addresses are always 4 bytes.
+		if (((*skb).nh.arph)->ar_pln != sizeof(uint32_t))
+			return EBT_NOMATCH;
+
+		if (info->bitmask & EBT_ARP_SRC_IP) {
+			memcpy(&src, ((*skb).nh.raw) + sizeof(struct arphdr) +
+			   ((*skb).nh.arph)->ar_hln, sizeof(uint32_t));
+			if (FWINV(info->saddr != (src & info->smsk),
+			   EBT_ARP_SRC_IP))
+				return EBT_NOMATCH;
+		}
+
+		if (info->bitmask & EBT_ARP_DST_IP) {
+			memcpy(&dst, ((*skb).nh.raw)+sizeof(struct arphdr) +
+			   (2*(((*skb).nh.arph)->ar_hln)) +
+			   (((*skb).nh.arph)->ar_pln), sizeof(uint32_t));
+			if (FWINV(info->daddr != (dst & info->dmsk),
+			   EBT_ARP_DST_IP))
+				return EBT_NOMATCH;
+		}
+	}
+
+	if (info->bitmask & (EBT_ARP_SRC_MAC | EBT_ARP_DST_MAC))
+	{
+		uint32_t arp_len = sizeof(struct arphdr) +
+		   (2 * (((*skb).nh.arph)->ar_hln)) +
+		   (2 * (((*skb).nh.arph)->ar_pln));
+		unsigned char dst[ETH_ALEN];
+		unsigned char src[ETH_ALEN];
+
+		// Make sure the packet is long enough.
+		if ((((*skb).nh.raw) + arp_len) > (*skb).tail)
+			return EBT_NOMATCH;
+		// MAC addresses are 6 bytes.
+		if (((*skb).nh.arph)->ar_hln != ETH_ALEN)
+			return EBT_NOMATCH;
+		if (info->bitmask & EBT_ARP_SRC_MAC) {
+			uint8_t verdict, i;
+
+			memcpy(&src, ((*skb).nh.raw) +
+					sizeof(struct arphdr),
+					ETH_ALEN);
+			verdict = 0;
+			for (i = 0; i < 6; i++)
+				verdict |= (src[i] ^ info->smaddr[i]) &
+				       info->smmsk[i];	
+			if (FWINV(verdict != 0, EBT_ARP_SRC_MAC))
+				return EBT_NOMATCH;
+		}
+
+		if (info->bitmask & EBT_ARP_DST_MAC) { 
+			uint8_t verdict, i;
+
+			memcpy(&dst, ((*skb).nh.raw) +
+					sizeof(struct arphdr) +
+			   		(((*skb).nh.arph)->ar_hln) +
+			   		(((*skb).nh.arph)->ar_pln),
+					ETH_ALEN);
+			verdict = 0;
+			for (i = 0; i < 6; i++)
+				verdict |= (dst[i] ^ info->dmaddr[i]) &
+					info->dmmsk[i];
+			if (FWINV(verdict != 0, EBT_ARP_DST_MAC))
+				return EBT_NOMATCH;
+		}
+	}
+
+	return EBT_MATCH;
+}
+
+static int ebt_arp_check(const char *tablename, unsigned int hookmask,
+   const struct ebt_entry *e, void *data, unsigned int datalen)
+{
+	struct ebt_arp_info *info = (struct ebt_arp_info *)data;
+
+	if (datalen != EBT_ALIGN(sizeof(struct ebt_arp_info)))
+		return -EINVAL;
+	if ((e->ethproto != __constant_htons(ETH_P_ARP) &&
+	   e->ethproto != __constant_htons(ETH_P_RARP)) ||
+	   e->invflags & EBT_IPROTO)
+		return -EINVAL;
+	if (info->bitmask & ~EBT_ARP_MASK || info->invflags & ~EBT_ARP_MASK)
+		return -EINVAL;
+	return 0;
+}
+
+static struct ebt_match filter_arp =
+{
+	{NULL, NULL}, EBT_ARP_MATCH, ebt_filter_arp, ebt_arp_check, NULL,
+	THIS_MODULE
+};
+
+static int __init init(void)
+{
+	return ebt_register_match(&filter_arp);
+}
+
+static void __exit fini(void)
+{
+	ebt_unregister_match(&filter_arp);
+}
+
+module_init(init);
+module_exit(fini);
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/net/bridge/netfilter/ebt_ip.c	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,121 @@
+/*
+ *  ebt_ip
+ *
+ *	Authors:
+ *	Bart De Schuymer <bart.de.schuymer@pandora.be>
+ *
+ *  April, 2002
+ *
+ *  Changes:
+ *    added ip-sport and ip-dport
+ *    Innominate Security Technologies AG <mhopf@innominate.com>
+ *    September, 2002
+ */
+
+#include <linux/netfilter_bridge/ebtables.h>
+#include <linux/netfilter_bridge/ebt_ip.h>
+#include <linux/ip.h>
+#include <linux/in.h>
+#include <linux/module.h>
+
+struct tcpudphdr {
+	uint16_t src;
+	uint16_t dst;
+};
+
+union h_u {
+	unsigned char *raw;
+	struct tcpudphdr *tuh;
+};
+
+static int ebt_filter_ip(const struct sk_buff *skb, const struct net_device *in,
+   const struct net_device *out, const void *data,
+   unsigned int datalen)
+{
+	struct ebt_ip_info *info = (struct ebt_ip_info *)data;
+
+	if (info->bitmask & EBT_IP_TOS &&
+	   FWINV(info->tos != ((*skb).nh.iph)->tos, EBT_IP_TOS))
+		return EBT_NOMATCH;
+	if (info->bitmask & EBT_IP_PROTO) {
+		if (FWINV(info->protocol != ((*skb).nh.iph)->protocol,
+		          EBT_IP_PROTO))
+			return EBT_NOMATCH;
+		if ( info->protocol == IPPROTO_TCP ||
+		     info->protocol == IPPROTO_UDP )
+		{
+			union h_u h;
+			h.raw = skb->data + skb->nh.iph->ihl*4;
+			if (info->bitmask & EBT_IP_DPORT) {
+				uint16_t port = ntohs(h.tuh->dst);
+				if (FWINV(port < info->dport[0] ||
+				          port > info->dport[1],
+				          EBT_IP_DPORT))
+				return EBT_NOMATCH;
+			}
+			if (info->bitmask & EBT_IP_SPORT) {
+				uint16_t port = ntohs(h.tuh->src);
+				if (FWINV(port < info->sport[0] ||
+				          port > info->sport[1],
+				          EBT_IP_SPORT))
+				return EBT_NOMATCH;
+			}
+		}
+	}
+	if (info->bitmask & EBT_IP_SOURCE &&
+	   FWINV((((*skb).nh.iph)->saddr & info->smsk) !=
+	   info->saddr, EBT_IP_SOURCE))
+		return EBT_NOMATCH;
+	if ((info->bitmask & EBT_IP_DEST) &&
+	   FWINV((((*skb).nh.iph)->daddr & info->dmsk) !=
+	   info->daddr, EBT_IP_DEST))
+		return EBT_NOMATCH;
+	return EBT_MATCH;
+}
+
+static int ebt_ip_check(const char *tablename, unsigned int hookmask,
+   const struct ebt_entry *e, void *data, unsigned int datalen)
+{
+	struct ebt_ip_info *info = (struct ebt_ip_info *)data;
+
+	if (datalen != EBT_ALIGN(sizeof(struct ebt_ip_info)))
+		return -EINVAL;
+	if (e->ethproto != __constant_htons(ETH_P_IP) ||
+	   e->invflags & EBT_IPROTO)
+		return -EINVAL;
+	if (info->bitmask & ~EBT_IP_MASK || info->invflags & ~EBT_IP_MASK)
+		return -EINVAL;
+	if (info->bitmask & (EBT_IP_DPORT | EBT_IP_SPORT)) {
+		if (!info->bitmask & EBT_IPROTO)
+			return -EINVAL;
+		if (info->protocol != IPPROTO_TCP &&
+		    info->protocol != IPPROTO_UDP)
+			 return -EINVAL;
+	}
+	if (info->bitmask & EBT_IP_DPORT && info->dport[0] > info->dport[1])
+		return -EINVAL;
+	if (info->bitmask & EBT_IP_SPORT && info->sport[0] > info->sport[1])
+		return -EINVAL;
+	return 0;
+}
+
+static struct ebt_match filter_ip =
+{
+	{NULL, NULL}, EBT_IP_MATCH, ebt_filter_ip, ebt_ip_check, NULL,
+	THIS_MODULE
+};
+
+static int __init init(void)
+{
+	return ebt_register_match(&filter_ip);
+}
+
+static void __exit fini(void)
+{
+	ebt_unregister_match(&filter_ip);
+}
+
+module_init(init);
+module_exit(fini);
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/net/bridge/netfilter/ebt_vlan.c	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,259 @@
+/*
+ * Description: EBTables 802.1Q match extension kernelspace module.
+ * Authors: Nick Fedchik <nick@fedchik.org.ua>
+ *          Bart De Schuymer <bart.de.schuymer@pandora.be>
+ *    
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/if_ether.h>
+#include <linux/if_vlan.h>
+#include <linux/module.h>
+#include <linux/netfilter_bridge/ebtables.h>
+#include <linux/netfilter_bridge/ebt_vlan.h>
+
+static unsigned char debug;
+#define MODULE_VERSION "0.6"
+
+MODULE_PARM(debug, "0-1b");
+MODULE_PARM_DESC(debug, "debug=1 is turn on debug messages");
+MODULE_AUTHOR("Nick Fedchik <nick@fedchik.org.ua>");
+MODULE_DESCRIPTION("802.1Q match module (ebtables extension), v"
+		   MODULE_VERSION);
+MODULE_LICENSE("GPL");
+
+
+#define DEBUG_MSG(args...) if (debug) printk (KERN_DEBUG "ebt_vlan: " args)
+#define INV_FLAG(_inv_flag_) (info->invflags & _inv_flag_) ? "!" : ""
+#define GET_BITMASK(_BIT_MASK_) info->bitmask & _BIT_MASK_
+#define SET_BITMASK(_BIT_MASK_) info->bitmask |= _BIT_MASK_
+#define EXIT_ON_MISMATCH(_MATCH_,_MASK_) if (!((info->_MATCH_ == _MATCH_)^!!(info->invflags & _MASK_))) return 1;
+
+/*
+ * Function description: ebt_filter_vlan() is main engine for 
+ * checking passed 802.1Q frame according to 
+ * the passed extension parameters (in the *data buffer)
+ * ebt_filter_vlan() is called after successfull check the rule params
+ * by ebt_check_vlan() function.
+ * Parameters:
+ * const struct sk_buff *skb - pointer to passed ethernet frame buffer
+ * const void *data - pointer to passed extension parameters
+ * unsigned int datalen - length of passed *data buffer
+ * const struct net_device *in  -
+ * const struct net_device *out -
+ * const struct ebt_counter *c -
+ * Returned values:
+ * 0 - ok (all rule params matched)
+ * 1 - miss (rule params not acceptable to the parsed frame)
+ */
+static int
+ebt_filter_vlan(const struct sk_buff *skb,
+		const struct net_device *in,
+		const struct net_device *out,
+		const void *data, unsigned int datalen)
+{
+	struct ebt_vlan_info *info = (struct ebt_vlan_info *) data;	/* userspace data */
+	struct vlan_ethhdr *frame = (struct vlan_ethhdr *) skb->mac.raw;	/* Passed tagged frame */
+
+	unsigned short TCI;	/* Whole TCI, given from parsed frame */
+	unsigned short id;	/* VLAN ID, given from frame TCI */
+	unsigned char prio;	/* user_priority, given from frame TCI */
+	unsigned short encap;	/* VLAN encapsulated Type/Length field, given from orig frame */
+
+	/*
+	 * Tag Control Information (TCI) consists of the following elements:
+	 * - User_priority. The user_priority field is three bits in length, 
+	 * interpreted as a binary number. 
+	 * - Canonical Format Indicator (CFI). The Canonical Format Indicator 
+	 * (CFI) is a single bit flag value. Currently ignored.
+	 * - VLAN Identifier (VID). The VID is encoded as 
+	 * an unsigned binary number. 
+	 */
+	TCI = ntohs(frame->h_vlan_TCI);
+	id = TCI & VLAN_VID_MASK;
+	prio = (TCI >> 13) & 0x7;
+	encap = frame->h_vlan_encapsulated_proto;
+
+	/*
+	 * Checking VLAN Identifier (VID)
+	 */
+	if (GET_BITMASK(EBT_VLAN_ID)) {	/* Is VLAN ID parsed? */
+		EXIT_ON_MISMATCH(id, EBT_VLAN_ID);
+	}
+	/*
+	 * Checking user_priority
+	 */
+	if (GET_BITMASK(EBT_VLAN_PRIO)) {	/* Is VLAN user_priority parsed? */
+		EXIT_ON_MISMATCH(prio, EBT_VLAN_PRIO);
+	}
+	/*
+	 * Checking Encapsulated Proto (Length/Type) field
+	 */
+	if (GET_BITMASK(EBT_VLAN_ENCAP)) {	/* Is VLAN Encap parsed? */
+		EXIT_ON_MISMATCH(encap, EBT_VLAN_ENCAP);
+	}
+	/*
+	 * All possible extension parameters was parsed.
+	 * If rule never returned by missmatch, then all ok.
+	 */
+	return 0;
+}
+
+/*
+ * Function description: ebt_vlan_check() is called when userspace 
+ * delivers the table entry to the kernel, 
+ * and to check that userspace doesn't give a bad table.
+ * Parameters:
+ * const char *tablename - table name string
+ * unsigned int hooknr - hook number
+ * const struct ebt_entry *e - ebtables entry basic set
+ * const void *data - pointer to passed extension parameters
+ * unsigned int datalen - length of passed *data buffer
+ * Returned values:
+ * 0 - ok (all delivered rule params are correct)
+ * 1 - miss (rule params is out of range, invalid, incompatible, etc.)
+ */
+static int
+ebt_check_vlan(const char *tablename,
+	       unsigned int hooknr,
+	       const struct ebt_entry *e, void *data, unsigned int datalen)
+{
+	struct ebt_vlan_info *info = (struct ebt_vlan_info *) data;
+
+	/*
+	 * Parameters buffer overflow check 
+	 */
+	if (datalen != EBT_ALIGN(sizeof(struct ebt_vlan_info))) {
+		DEBUG_MSG
+		    ("passed size %d is not eq to ebt_vlan_info (%d)\n",
+		     datalen, sizeof(struct ebt_vlan_info));
+		return -EINVAL;
+	}
+
+	/*
+	 * Is it 802.1Q frame checked?
+	 */
+	if (e->ethproto != __constant_htons(ETH_P_8021Q)) {
+		DEBUG_MSG
+		    ("passed entry proto %2.4X is not 802.1Q (8100)\n",
+		     (unsigned short) ntohs(e->ethproto));
+		return -EINVAL;
+	}
+
+	/*
+	 * Check for bitmask range 
+	 * True if even one bit is out of mask
+	 */
+	if (info->bitmask & ~EBT_VLAN_MASK) {
+		DEBUG_MSG("bitmask %2X is out of mask (%2X)\n",
+			  info->bitmask, EBT_VLAN_MASK);
+		return -EINVAL;
+	}
+
+	/*
+	 * Check for inversion flags range 
+	 */
+	if (info->invflags & ~EBT_VLAN_MASK) {
+		DEBUG_MSG("inversion flags %2X is out of mask (%2X)\n",
+			  info->invflags, EBT_VLAN_MASK);
+		return -EINVAL;
+	}
+
+	/*
+	 * Reserved VLAN ID (VID) values
+	 * -----------------------------
+	 * 0 - The null VLAN ID. 
+	 * 1 - The default Port VID (PVID)
+	 * 0x0FFF - Reserved for implementation use. 
+	 * if_vlan.h: VLAN_GROUP_ARRAY_LEN 4096.
+	 */
+	if (GET_BITMASK(EBT_VLAN_ID)) {	/* when vlan-id param was spec-ed */
+		if (!!info->id) {	/* if id!=0 => check vid range */
+			if (info->id > VLAN_GROUP_ARRAY_LEN) {
+				DEBUG_MSG
+				    ("id %d is out of range (1-4096)\n",
+				     info->id);
+				return -EINVAL;
+			}
+			/*
+			 * Note: This is valid VLAN-tagged frame point.
+			 * Any value of user_priority are acceptable, 
+			 * but should be ignored according to 802.1Q Std.
+			 * So we just drop the prio flag. 
+			 */
+			info->bitmask &= ~EBT_VLAN_PRIO;
+		}
+		/*
+		 * Else, id=0 (null VLAN ID)  => user_priority range (any?)
+		 */
+	}
+
+	if (GET_BITMASK(EBT_VLAN_PRIO)) {
+		if ((unsigned char) info->prio > 7) {
+			DEBUG_MSG
+			    ("prio %d is out of range (0-7)\n",
+			     info->prio);
+			return -EINVAL;
+		}
+	}
+	/*
+	 * Check for encapsulated proto range - it is possible to be 
+	 * any value for u_short range.
+	 * if_ether.h:  ETH_ZLEN        60   -  Min. octets in frame sans FCS
+	 */
+	if (GET_BITMASK(EBT_VLAN_ENCAP)) {
+		if ((unsigned short) ntohs(info->encap) < ETH_ZLEN) {
+			DEBUG_MSG
+			    ("encap frame length %d is less than minimal\n",
+			     ntohs(info->encap));
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+static struct ebt_match filter_vlan = {
+	{NULL, NULL},
+	EBT_VLAN_MATCH,
+	ebt_filter_vlan,
+	ebt_check_vlan,
+	NULL,
+	THIS_MODULE
+};
+
+/*
+ * Module initialization function.
+ */
+static int __init init(void)
+{
+	DEBUG_MSG("ebtables 802.1Q extension module v"
+		  MODULE_VERSION "\n");
+	DEBUG_MSG("module debug=%d\n", !!debug);
+	return ebt_register_match(&filter_vlan);
+}
+
+/*
+ * Module "finalization" function
+ */
+static void __exit fini(void)
+{
+	ebt_unregister_match(&filter_vlan);
+}
+
+module_init(init);
+module_exit(fini);
+
+EXPORT_NO_SYMBOLS;
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/net/bridge/netfilter/ebt_log.c	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,152 @@
+/*
+ *  ebt_log
+ *
+ *	Authors:
+ *	Bart De Schuymer <bart.de.schuymer@pandora.be>
+ *
+ *  April, 2002
+ *
+ */
+
+#include <linux/netfilter_bridge/ebtables.h>
+#include <linux/netfilter_bridge/ebt_log.h>
+#include <linux/module.h>
+#include <linux/ip.h>
+#include <linux/in.h>
+#include <linux/if_arp.h>
+#include <linux/spinlock.h>
+
+static spinlock_t ebt_log_lock = SPIN_LOCK_UNLOCKED;
+
+static int ebt_log_check(const char *tablename, unsigned int hookmask,
+   const struct ebt_entry *e, void *data, unsigned int datalen)
+{
+	struct ebt_log_info *info = (struct ebt_log_info *)data;
+
+	if (datalen != EBT_ALIGN(sizeof(struct ebt_log_info)))
+		return -EINVAL;
+	if (info->bitmask & ~EBT_LOG_MASK)
+		return -EINVAL;
+	if (info->loglevel >= 8)
+		return -EINVAL;
+	info->prefix[EBT_LOG_PREFIX_SIZE - 1] = '\0';
+	return 0;
+}
+
+struct tcpudphdr
+{
+	uint16_t src;
+	uint16_t dst;
+};
+
+struct arppayload
+{
+	unsigned char mac_src[ETH_ALEN];
+	unsigned char ip_src[4];
+	unsigned char mac_dst[ETH_ALEN];
+	unsigned char ip_dst[4];
+};
+
+static void print_MAC(unsigned char *p)
+{
+	int i;
+
+	for (i = 0; i < ETH_ALEN; i++, p++)
+		printk("%02x%c", *p, i == ETH_ALEN - 1 ? ' ':':');
+}
+
+#define myNIPQUAD(a) a[0], a[1], a[2], a[3]
+static void ebt_log(const struct sk_buff *skb, const struct net_device *in,
+   const struct net_device *out, const void *data, unsigned int datalen)
+{
+	struct ebt_log_info *info = (struct ebt_log_info *)data;
+	char level_string[4] = "< >";
+	level_string[1] = '0' + info->loglevel;
+
+	spin_lock_bh(&ebt_log_lock);
+	printk(level_string);
+	printk("%s IN=%s OUT=%s ", info->prefix, in ? in->name : "",
+	   out ? out->name : "");
+
+	printk("MAC source = ");
+	print_MAC((skb->mac.ethernet)->h_source);
+	printk("MAC dest = ");
+	print_MAC((skb->mac.ethernet)->h_dest);
+
+	printk("proto = 0x%04x", ntohs(((*skb).mac.ethernet)->h_proto));
+
+	if ((info->bitmask & EBT_LOG_IP) && skb->mac.ethernet->h_proto ==
+	   htons(ETH_P_IP)){
+		struct iphdr *iph = skb->nh.iph;
+		printk(" IP SRC=%u.%u.%u.%u IP DST=%u.%u.%u.%u,",
+		   NIPQUAD(iph->saddr), NIPQUAD(iph->daddr));
+		printk(" IP tos=0x%02X, IP proto=%d", iph->tos, iph->protocol);
+		if (iph->protocol == IPPROTO_TCP ||
+		    iph->protocol == IPPROTO_UDP) {
+			struct tcpudphdr *ports = (struct tcpudphdr *)(skb->data + iph->ihl*4);
+
+			if (skb->data + iph->ihl*4 > skb->tail) {
+				printk(" INCOMPLETE TCP/UDP header");
+				goto out;
+			}
+			printk(" SPT=%u DPT=%u", ntohs(ports->src),
+			   ntohs(ports->dst));
+		}
+		goto out;
+	}
+
+	if ((info->bitmask & EBT_LOG_ARP) &&
+	    ((skb->mac.ethernet->h_proto == __constant_htons(ETH_P_ARP)) ||
+	    (skb->mac.ethernet->h_proto == __constant_htons(ETH_P_RARP)))) {
+		struct arphdr * arph = skb->nh.arph;
+		printk(" ARP HTYPE=%d, PTYPE=0x%04x, OPCODE=%d",
+		   ntohs(arph->ar_hrd), ntohs(arph->ar_pro),
+		   ntohs(arph->ar_op));
+		/* If it's for Ethernet and the lengths are OK,
+		 * then log the ARP payload */
+		if (arph->ar_hrd == __constant_htons(1) &&
+		    arph->ar_hln == ETH_ALEN &&
+		    arph->ar_pln == sizeof(uint32_t)) {
+			struct arppayload *arpp = (struct arppayload *)(skb->data + sizeof(*arph));
+
+			if (skb->data + sizeof(*arph) > skb->tail) {
+				printk(" INCOMPLETE ARP header");
+				goto out;
+			}
+
+			printk(" ARP MAC SRC=");
+			print_MAC(arpp->mac_src);
+			printk(" ARP IP SRC=%u.%u.%u.%u",
+			       myNIPQUAD(arpp->ip_src));
+			printk(" ARP MAC DST=");
+			print_MAC(arpp->mac_dst);
+			printk(" ARP IP DST=%u.%u.%u.%u",
+			       myNIPQUAD(arpp->ip_dst));
+		}
+
+	}
+out:
+	printk("\n");
+	spin_unlock_bh(&ebt_log_lock);
+}
+
+static struct ebt_watcher log =
+{
+	{NULL, NULL}, EBT_LOG_WATCHER, ebt_log, ebt_log_check, NULL,
+	THIS_MODULE
+};
+
+static int __init init(void)
+{
+	return ebt_register_watcher(&log);
+}
+
+static void __exit fini(void)
+{
+	ebt_unregister_watcher(&log);
+}
+
+module_init(init);
+module_exit(fini);
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/net/bridge/netfilter/ebt_snat.c	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,64 @@
+/*
+ *  ebt_snat
+ *
+ *	Authors:
+ *	Bart De Schuymer <bart.de.schuymer@pandora.be>
+ *
+ *  June, 2002
+ *
+ */
+
+#include <linux/netfilter_bridge/ebtables.h>
+#include <linux/netfilter_bridge/ebt_nat.h>
+#include <linux/module.h>
+
+static int ebt_target_snat(struct sk_buff **pskb, unsigned int hooknr,
+   const struct net_device *in, const struct net_device *out,
+   const void *data, unsigned int datalen)
+{
+	struct ebt_nat_info *info = (struct ebt_nat_info *) data;
+
+	memcpy(((**pskb).mac.ethernet)->h_source, info->mac,
+	   ETH_ALEN * sizeof(unsigned char));
+	return info->target;
+}
+
+static int ebt_target_snat_check(const char *tablename, unsigned int hookmask,
+   const struct ebt_entry *e, void *data, unsigned int datalen)
+{
+	struct ebt_nat_info *info = (struct ebt_nat_info *) data;
+
+	if (datalen != EBT_ALIGN(sizeof(struct ebt_nat_info)))
+		return -EINVAL;
+	if (BASE_CHAIN && info->target == EBT_RETURN)
+		return -EINVAL;
+	CLEAR_BASE_CHAIN_BIT;
+	if (strcmp(tablename, "nat"))
+		return -EINVAL;
+	if (hookmask & ~(1 << NF_BR_POST_ROUTING))
+		return -EINVAL;
+	if (INVALID_TARGET)
+		return -EINVAL;
+	return 0;
+}
+
+static struct ebt_target snat =
+{
+	{NULL, NULL}, EBT_SNAT_TARGET, ebt_target_snat, ebt_target_snat_check,
+	NULL, THIS_MODULE
+};
+
+static int __init init(void)
+{
+	return ebt_register_target(&snat);
+}
+
+static void __exit fini(void)
+{
+	ebt_unregister_target(&snat);
+}
+
+module_init(init);
+module_exit(fini);
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/net/bridge/netfilter/ebt_dnat.c	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,65 @@
+/*
+ *  ebt_dnat
+ *
+ *	Authors:
+ *	Bart De Schuymer <bart.de.schuymer@pandora.be>
+ *
+ *  June, 2002
+ *
+ */
+
+#include <linux/netfilter_bridge/ebtables.h>
+#include <linux/netfilter_bridge/ebt_nat.h>
+#include <linux/module.h>
+#include <net/sock.h>
+
+static int ebt_target_dnat(struct sk_buff **pskb, unsigned int hooknr,
+   const struct net_device *in, const struct net_device *out,
+   const void *data, unsigned int datalen)
+{
+	struct ebt_nat_info *info = (struct ebt_nat_info *)data;
+
+	memcpy(((**pskb).mac.ethernet)->h_dest, info->mac,
+	   ETH_ALEN * sizeof(unsigned char));
+	return info->target;
+}
+
+static int ebt_target_dnat_check(const char *tablename, unsigned int hookmask,
+   const struct ebt_entry *e, void *data, unsigned int datalen)
+{
+	struct ebt_nat_info *info = (struct ebt_nat_info *)data;
+
+	if (BASE_CHAIN && info->target == EBT_RETURN)
+		return -EINVAL;
+	CLEAR_BASE_CHAIN_BIT;
+	if ( (strcmp(tablename, "nat") ||
+	   (hookmask & ~((1 << NF_BR_PRE_ROUTING) | (1 << NF_BR_LOCAL_OUT)))) &&
+	   (strcmp(tablename, "broute") || hookmask & ~(1 << NF_BR_BROUTING)) )
+		return -EINVAL;
+	if (datalen != EBT_ALIGN(sizeof(struct ebt_nat_info)))
+		return -EINVAL;
+	if (INVALID_TARGET)
+		return -EINVAL;
+	return 0;
+}
+
+static struct ebt_target dnat =
+{
+	{NULL, NULL}, EBT_DNAT_TARGET, ebt_target_dnat, ebt_target_dnat_check,
+	NULL, THIS_MODULE
+};
+
+static int __init init(void)
+{
+	return ebt_register_target(&dnat);
+}
+
+static void __exit fini(void)
+{
+	ebt_unregister_target(&dnat);
+}
+
+module_init(init);
+module_exit(fini);
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/net/bridge/netfilter/ebtables.c	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,1490 @@
+/*
+ *  ebtables
+ *
+ *  Author:
+ *  Bart De Schuymer		<bart.de.schuymer@pandora.be>
+ *
+ *  ebtables.c,v 2.0, July, 2002
+ *
+ *  This code is stongly inspired on the iptables code which is
+ *  Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  as published by the Free Software Foundation; either version
+ *  2 of the License, or (at your option) any later version.
+ */
+
+// used for print_string
+#include <linux/sched.h>
+#include <linux/tty.h>
+
+#include <linux/kmod.h>
+#include <linux/module.h>
+#include <linux/vmalloc.h>
+#include <linux/netfilter_bridge/ebtables.h>
+#include <linux/spinlock.h>
+#include <asm/uaccess.h>
+#include <linux/smp.h>
+#include <net/sock.h>
+// needed for logical [in,out]-dev filtering
+#include "../br_private.h"
+
+// list_named_find
+#define ASSERT_READ_LOCK(x)
+#define ASSERT_WRITE_LOCK(x)
+#include <linux/netfilter_ipv4/listhelp.h>
+
+#if 0 // use this for remote debugging
+// Copyright (C) 1998 by Ori Pomerantz
+// Print the string to the appropriate tty, the one
+// the current task uses
+static void print_string(char *str)
+{
+	struct tty_struct *my_tty;
+
+	/* The tty for the current task */
+	my_tty = current->tty;
+	if (my_tty != NULL) {
+		(*(my_tty->driver).write)(my_tty, 0, str, strlen(str));
+		(*(my_tty->driver).write)(my_tty, 0, "\015\012", 2);
+	}
+}
+
+#define BUGPRINT(args) print_string(args);
+#else
+#define BUGPRINT(format, args...) printk("kernel msg: ebtables bug: please "\
+                                         "report to author: "format, ## args)
+// #define BUGPRINT(format, args...)
+#endif
+#define MEMPRINT(format, args...) printk("kernel msg: ebtables "\
+                                         ": out of memory: "format, ## args)
+// #define MEMPRINT(format, args...)
+
+
+
+// Each cpu has its own set of counters, so there is no need for write_lock in
+// the softirq
+// For reading or updating the counters, the user context needs to
+// get a write_lock
+
+// The size of each set of counters is altered to get cache alignment
+#define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1))
+#define COUNTER_OFFSET(n) (SMP_ALIGN(n * sizeof(struct ebt_counter)))
+#define COUNTER_BASE(c, n, cpu) ((struct ebt_counter *)(((char *)c) + \
+   COUNTER_OFFSET(n) * cpu))
+
+
+
+static DECLARE_MUTEX(ebt_mutex);
+static LIST_HEAD(ebt_tables);
+static LIST_HEAD(ebt_targets);
+static LIST_HEAD(ebt_matches);
+static LIST_HEAD(ebt_watchers);
+
+static struct ebt_target ebt_standard_target =
+{ {NULL, NULL}, EBT_STANDARD_TARGET, NULL, NULL, NULL, NULL};
+
+static inline int ebt_do_watcher (struct ebt_entry_watcher *w,
+   const struct sk_buff *skb, const struct net_device *in,
+   const struct net_device *out)
+{
+	w->u.watcher->watcher(skb, in, out, w->data,
+	   w->watcher_size);
+	// watchers don't give a verdict
+	return 0;
+}
+
+static inline int ebt_do_match (struct ebt_entry_match *m,
+   const struct sk_buff *skb, const struct net_device *in,
+   const struct net_device *out)
+{
+	return m->u.match->match(skb, in, out, m->data,
+	   m->match_size);
+}
+
+static inline int ebt_dev_check(char *entry, const struct net_device *device)
+{
+	if (*entry == '\0')
+		return 0;
+	if (!device)
+		return 1;
+	return !!strcmp(entry, device->name);
+}
+
+#define FWINV2(bool,invflg) ((bool) ^ !!(e->invflags & invflg))
+// process standard matches
+static inline int ebt_basic_match(struct ebt_entry *e, struct ethhdr *h,
+   const struct net_device *in, const struct net_device *out)
+{
+	int verdict, i;
+
+	if (e->bitmask & EBT_802_3) {
+		if (FWINV2(ntohs(h->h_proto) >= 1536, EBT_IPROTO))
+			return 1;
+	} else if (!(e->bitmask & EBT_NOPROTO) &&
+	   FWINV2(e->ethproto != h->h_proto, EBT_IPROTO))
+		return 1;
+
+	if (FWINV2(ebt_dev_check(e->in, in), EBT_IIN))
+		return 1;
+	if (FWINV2(ebt_dev_check(e->out, out), EBT_IOUT))
+		return 1;
+	if ((!in || !in->br_port) ? 0 : FWINV2(ebt_dev_check(
+	   e->logical_in, &in->br_port->br->dev), EBT_ILOGICALIN))
+		return 1;
+	if ((!out || !out->br_port) ? 0 : FWINV2(ebt_dev_check(
+	   e->logical_out, &out->br_port->br->dev), EBT_ILOGICALOUT))
+		return 1;
+
+	if (e->bitmask & EBT_SOURCEMAC) {
+		verdict = 0;
+		for (i = 0; i < 6; i++)
+			verdict |= (h->h_source[i] ^ e->sourcemac[i]) &
+			   e->sourcemsk[i];
+		if (FWINV2(verdict != 0, EBT_ISOURCE) )
+			return 1;
+	}
+	if (e->bitmask & EBT_DESTMAC) {
+		verdict = 0;
+		for (i = 0; i < 6; i++)
+			verdict |= (h->h_dest[i] ^ e->destmac[i]) &
+			   e->destmsk[i];
+		if (FWINV2(verdict != 0, EBT_IDEST) )
+			return 1;
+	}
+	return 0;
+}
+
+// Do some firewalling
+unsigned int ebt_do_table (unsigned int hook, struct sk_buff **pskb,
+   const struct net_device *in, const struct net_device *out,
+   struct ebt_table *table)
+{
+	int i, nentries;
+	struct ebt_entry *point;
+	struct ebt_counter *counter_base, *cb_base;
+	struct ebt_entry_target *t;
+	int verdict, sp = 0;
+	struct ebt_chainstack *cs;
+	struct ebt_entries *chaininfo;
+	char *base;
+	struct ebt_table_info *private = table->private;
+
+	read_lock_bh(&table->lock);
+	cb_base = COUNTER_BASE(private->counters, private->nentries,
+	   cpu_number_map(smp_processor_id()));
+	if (private->chainstack)
+		cs = private->chainstack[cpu_number_map(smp_processor_id())];
+	else
+		cs = NULL;
+	chaininfo = private->hook_entry[hook];
+	nentries = private->hook_entry[hook]->nentries;
+	point = (struct ebt_entry *)(private->hook_entry[hook]->data);
+	counter_base = cb_base + private->hook_entry[hook]->counter_offset;
+	// base for chain jumps
+	base = private->entries;
+	i = 0;
+	while (i < nentries) {
+		if (ebt_basic_match(point, (**pskb).mac.ethernet, in, out))
+			goto letscontinue;
+
+		if (EBT_MATCH_ITERATE(point, ebt_do_match, *pskb, in, out) != 0)
+			goto letscontinue;
+
+		// increase counter
+		(*(counter_base + i)).pcnt++;
+		(*(counter_base + i)).bcnt+=(**pskb).len;
+
+		// these should only watch: not modify, nor tell us
+		// what to do with the packet
+		EBT_WATCHER_ITERATE(point, ebt_do_watcher, *pskb, in,
+		   out);
+
+		t = (struct ebt_entry_target *)
+		   (((char *)point) + point->target_offset);
+		// standard target
+		if (!t->u.target->target)
+			verdict = ((struct ebt_standard_target *)t)->verdict;
+		else
+			verdict = t->u.target->target(pskb, hook,
+			   in, out, t->data, t->target_size);
+		if (verdict == EBT_ACCEPT) {
+			read_unlock_bh(&table->lock);
+			return NF_ACCEPT;
+		}
+		if (verdict == EBT_DROP) {
+			read_unlock_bh(&table->lock);
+			return NF_DROP;
+		}
+		if (verdict == EBT_RETURN) {
+letsreturn:
+#ifdef CONFIG_NETFILTER_DEBUG
+			if (sp == 0) {
+				BUGPRINT("RETURN on base chain");
+				// act like this is EBT_CONTINUE
+				goto letscontinue;
+			}
+#endif
+			sp--;
+			// put all the local variables right
+			i = cs[sp].n;
+			chaininfo = cs[sp].chaininfo;
+			nentries = chaininfo->nentries;
+			point = cs[sp].e;
+			counter_base = cb_base +
+			   chaininfo->counter_offset;
+			continue;
+		}
+		if (verdict == EBT_CONTINUE)
+			goto letscontinue;
+#ifdef CONFIG_NETFILTER_DEBUG
+		if (verdict < 0) {
+			BUGPRINT("bogus standard verdict\n");
+			read_unlock_bh(&table->lock);
+			return NF_DROP;
+		}
+#endif
+		// jump to a udc
+		cs[sp].n = i + 1;
+		cs[sp].chaininfo = chaininfo;
+		cs[sp].e = (struct ebt_entry *)
+		   (((char *)point) + point->next_offset);
+		i = 0;
+		chaininfo = (struct ebt_entries *) (base + verdict);
+#ifdef CONFIG_NETFILTER_DEBUG
+		if (chaininfo->distinguisher) {
+			BUGPRINT("jump to non-chain\n");
+			read_unlock_bh(&table->lock);
+			return NF_DROP;
+		}
+#endif
+		nentries = chaininfo->nentries;
+		point = (struct ebt_entry *)chaininfo->data;
+		counter_base = cb_base + chaininfo->counter_offset;
+		sp++;
+		continue;
+letscontinue:
+		point = (struct ebt_entry *)
+		   (((char *)point) + point->next_offset);
+		i++;
+	}
+
+	// I actually like this :)
+	if (chaininfo->policy == EBT_RETURN)
+		goto letsreturn;
+	if (chaininfo->policy == EBT_ACCEPT) {
+		read_unlock_bh(&table->lock);
+		return NF_ACCEPT;
+	}
+	read_unlock_bh(&table->lock);
+	return NF_DROP;
+}
+
+// If it succeeds, returns element and locks mutex
+static inline void *
+find_inlist_lock_noload(struct list_head *head, const char *name, int *error,
+   struct semaphore *mutex)
+{
+	void *ret;
+
+	*error = down_interruptible(mutex);
+	if (*error != 0)
+		return NULL;
+
+	ret = list_named_find(head, name);
+	if (!ret) {
+		*error = -ENOENT;
+		up(mutex);
+	}
+	return ret;
+}
+
+#ifndef CONFIG_KMOD
+#define find_inlist_lock(h,n,p,e,m) find_inlist_lock_noload((h),(n),(e),(m))
+#else
+static void *
+find_inlist_lock(struct list_head *head, const char *name, const char *prefix,
+   int *error, struct semaphore *mutex)
+{
+	void *ret;
+
+	ret = find_inlist_lock_noload(head, name, error, mutex);
+	if (!ret) {
+		char modulename[EBT_FUNCTION_MAXNAMELEN + strlen(prefix) + 1];
+		strcpy(modulename, prefix);
+		strcat(modulename, name);
+		request_module(modulename);
+		ret = find_inlist_lock_noload(head, name, error, mutex);
+	}
+	return ret;
+}
+#endif
+
+static inline struct ebt_table *
+find_table_lock(const char *name, int *error, struct semaphore *mutex)
+{
+	return find_inlist_lock(&ebt_tables, name, "ebtable_", error, mutex);
+}
+
+static inline struct ebt_match *
+find_match_lock(const char *name, int *error, struct semaphore *mutex)
+{
+	return find_inlist_lock(&ebt_matches, name, "ebt_", error, mutex);
+}
+
+static inline struct ebt_watcher *
+find_watcher_lock(const char *name, int *error, struct semaphore *mutex)
+{
+	return find_inlist_lock(&ebt_watchers, name, "ebt_", error, mutex);
+}
+
+static inline struct ebt_target *
+find_target_lock(const char *name, int *error, struct semaphore *mutex)
+{
+	return find_inlist_lock(&ebt_targets, name, "ebt_", error, mutex);
+}
+
+static inline int
+ebt_check_match(struct ebt_entry_match *m, struct ebt_entry *e,
+   const char *name, unsigned int hookmask, unsigned int *cnt)
+{
+	struct ebt_match *match;
+	int ret;
+
+	if (((char *)m) + m->match_size + sizeof(struct ebt_entry_match) >
+	   ((char *)e) + e->watchers_offset)
+		return -EINVAL;
+	match = find_match_lock(m->u.name, &ret, &ebt_mutex);
+	if (!match)
+		return ret;
+	m->u.match = match;
+	if (match->me)
+		__MOD_INC_USE_COUNT(match->me);
+	up(&ebt_mutex);
+	if (match->check &&
+	   match->check(name, hookmask, e, m->data, m->match_size) != 0) {
+		BUGPRINT("match->check failed\n");
+		if (match->me)
+			__MOD_DEC_USE_COUNT(match->me);
+		return -EINVAL;
+	}
+	(*cnt)++;
+	return 0;
+}
+
+static inline int
+ebt_check_watcher(struct ebt_entry_watcher *w, struct ebt_entry *e,
+   const char *name, unsigned int hookmask, unsigned int *cnt)
+{
+	struct ebt_watcher *watcher;
+	int ret;
+
+	if (((char *)w) + w->watcher_size + sizeof(struct ebt_entry_watcher) >
+	   ((char *)e) + e->target_offset)
+		return -EINVAL;
+	watcher = find_watcher_lock(w->u.name, &ret, &ebt_mutex);
+	if (!watcher)
+		return ret;
+	w->u.watcher = watcher;
+	if (watcher->me)
+		__MOD_INC_USE_COUNT(watcher->me);
+	up(&ebt_mutex);
+	if (watcher->check &&
+	   watcher->check(name, hookmask, e, w->data, w->watcher_size) != 0) {
+		BUGPRINT("watcher->check failed\n");
+		if (watcher->me)
+			__MOD_DEC_USE_COUNT(watcher->me);
+		return -EINVAL;
+	}
+	(*cnt)++;
+	return 0;
+}
+
+// this one is very careful, as it is the first function
+// to parse the userspace data
+static inline int
+ebt_check_entry_size_and_hooks(struct ebt_entry *e,
+   struct ebt_table_info *newinfo, char *base, char *limit,
+   struct ebt_entries **hook_entries, unsigned int *n, unsigned int *cnt,
+   unsigned int *totalcnt, unsigned int *udc_cnt, unsigned int valid_hooks)
+{
+	int i;
+
+	for (i = 0; i < NF_BR_NUMHOOKS; i++) {
+		if ((valid_hooks & (1 << i)) == 0)
+			continue;
+		if ( (char *)hook_entries[i] - base ==
+		   (char *)e - newinfo->entries)
+			break;
+	}
+	// beginning of a new chain
+	// if i == NF_BR_NUMHOOKS it must be a user defined chain
+	if (i != NF_BR_NUMHOOKS || !(e->bitmask & EBT_ENTRY_OR_ENTRIES)) {
+		if ((e->bitmask & EBT_ENTRY_OR_ENTRIES) != 0) {
+			// we make userspace set this right,
+			// so there is no misunderstanding
+			BUGPRINT("EBT_ENTRY_OR_ENTRIES shouldn't be set "
+			         "in distinguisher\n");
+			return -EINVAL;
+		}
+		// this checks if the previous chain has as many entries
+		// as it said it has
+		if (*n != *cnt) {
+			BUGPRINT("nentries does not equal the nr of entries "
+		                 "in the chain\n");
+			return -EINVAL;
+		}
+		// before we look at the struct, be sure it is not too big
+		if ((char *)hook_entries[i] + sizeof(struct ebt_entries)
+		   > limit) {
+			BUGPRINT("entries_size too small\n");
+			return -EINVAL;
+		}
+		if (((struct ebt_entries *)e)->policy != EBT_DROP &&
+		   ((struct ebt_entries *)e)->policy != EBT_ACCEPT) {
+			// only RETURN from udc
+			if (i != NF_BR_NUMHOOKS ||
+			   ((struct ebt_entries *)e)->policy != EBT_RETURN) {
+				BUGPRINT("bad policy\n");
+				return -EINVAL;
+			}
+		}
+		if (i == NF_BR_NUMHOOKS) // it's a user defined chain
+			(*udc_cnt)++;
+		else
+			newinfo->hook_entry[i] = (struct ebt_entries *)e;
+		if (((struct ebt_entries *)e)->counter_offset != *totalcnt) {
+			BUGPRINT("counter_offset != totalcnt");
+			return -EINVAL;
+		}
+		*n = ((struct ebt_entries *)e)->nentries;
+		*cnt = 0;
+		return 0;
+	}
+	// a plain old entry, heh
+	if (sizeof(struct ebt_entry) > e->watchers_offset ||
+	   e->watchers_offset > e->target_offset ||
+	   e->target_offset >= e->next_offset) {
+		BUGPRINT("entry offsets not in right order\n");
+		return -EINVAL;
+	}
+	// this is not checked anywhere else
+	if (e->next_offset - e->target_offset < sizeof(struct ebt_entry_target)) {
+		BUGPRINT("target size too small\n");
+		return -EINVAL;
+	}
+
+	(*cnt)++;
+	(*totalcnt)++;
+	return 0;
+}
+
+struct ebt_cl_stack
+{
+	struct ebt_chainstack cs;
+	int from;
+	unsigned int hookmask;
+};
+
+// we need these positions to check that the jumps to a different part of the
+// entries is a jump to the beginning of a new chain.
+static inline int
+ebt_get_udc_positions(struct ebt_entry *e, struct ebt_table_info *newinfo,
+   struct ebt_entries **hook_entries, unsigned int *n, unsigned int valid_hooks,
+   struct ebt_cl_stack *udc)
+{
+	int i;
+
+	// we're only interested in chain starts
+	if (e->bitmask & EBT_ENTRY_OR_ENTRIES)
+		return 0;
+	for (i = 0; i < NF_BR_NUMHOOKS; i++) {
+		if ((valid_hooks & (1 << i)) == 0)
+			continue;
+		if (newinfo->hook_entry[i] == (struct ebt_entries *)e)
+			break;
+	}
+	// only care about udc
+	if (i != NF_BR_NUMHOOKS)
+		return 0;
+
+	udc[*n].cs.chaininfo = (struct ebt_entries *)e;
+	// these initialisations are depended on later in check_chainloops()
+	udc[*n].cs.n = 0;
+	udc[*n].hookmask = 0;
+
+	(*n)++;
+	return 0;
+}
+
+static inline int
+ebt_cleanup_match(struct ebt_entry_match *m, unsigned int *i)
+{
+	if (i && (*i)-- == 0)
+		return 1;
+	if (m->u.match->destroy)
+		m->u.match->destroy(m->data, m->match_size);
+	if (m->u.match->me)
+		__MOD_DEC_USE_COUNT(m->u.match->me);
+
+	return 0;
+}
+
+static inline int
+ebt_cleanup_watcher(struct ebt_entry_watcher *w, unsigned int *i)
+{
+	if (i && (*i)-- == 0)
+		return 1;
+	if (w->u.watcher->destroy)
+		w->u.watcher->destroy(w->data, w->watcher_size);
+	if (w->u.watcher->me)
+		__MOD_DEC_USE_COUNT(w->u.watcher->me);
+
+	return 0;
+}
+
+static inline int
+ebt_cleanup_entry(struct ebt_entry *e, unsigned int *cnt)
+{
+	struct ebt_entry_target *t;
+
+	if ((e->bitmask & EBT_ENTRY_OR_ENTRIES) == 0)
+		return 0;
+	// we're done
+	if (cnt && (*cnt)-- == 0)
+		return 1;
+	EBT_WATCHER_ITERATE(e, ebt_cleanup_watcher, NULL);
+	EBT_MATCH_ITERATE(e, ebt_cleanup_match, NULL);
+	t = (struct ebt_entry_target *)(((char *)e) + e->target_offset);
+	if (t->u.target->destroy)
+		t->u.target->destroy(t->data, t->target_size);
+	if (t->u.target->me)
+		__MOD_DEC_USE_COUNT(t->u.target->me);
+
+	return 0;
+}
+
+static inline int
+ebt_check_entry(struct ebt_entry *e, struct ebt_table_info *newinfo,
+   const char *name, unsigned int *cnt, unsigned int valid_hooks,
+   struct ebt_cl_stack *cl_s, unsigned int udc_cnt)
+{
+	struct ebt_entry_target *t;
+	struct ebt_target *target;
+	unsigned int i, j, hook = 0, hookmask = 0;
+	int ret;
+
+	// Don't mess with the struct ebt_entries
+	if ((e->bitmask & EBT_ENTRY_OR_ENTRIES) == 0)
+		return 0;
+
+	if (e->bitmask & ~EBT_F_MASK) {
+		BUGPRINT("Unknown flag for bitmask\n");
+		return -EINVAL;
+	}
+	if (e->invflags & ~EBT_INV_MASK) {
+		BUGPRINT("Unknown flag for inv bitmask\n");
+		return -EINVAL;
+	}
+	if ( (e->bitmask & EBT_NOPROTO) && (e->bitmask & EBT_802_3) ) {
+		BUGPRINT("NOPROTO & 802_3 not allowed\n");
+		return -EINVAL;
+	}
+	// what hook do we belong to?
+	for (i = 0; i < NF_BR_NUMHOOKS; i++) {
+		if ((valid_hooks & (1 << i)) == 0)
+			continue;
+		if ((char *)newinfo->hook_entry[i] < (char *)e)
+			hook = i;
+		else
+			break;
+	}
+	// (1 << NF_BR_NUMHOOKS) tells the check functions the rule is on
+	// a base chain
+	if (i < NF_BR_NUMHOOKS)
+		hookmask = (1 << hook) | (1 << NF_BR_NUMHOOKS);
+	else {
+		for (i = 0; i < udc_cnt; i++)
+			if ((char *)(cl_s[i].cs.chaininfo) > (char *)e)
+				break;
+		if (i == 0)
+			hookmask = (1 << hook) | (1 << NF_BR_NUMHOOKS);
+		else
+			hookmask = cl_s[i - 1].hookmask;
+	}
+	i = 0;
+	ret = EBT_MATCH_ITERATE(e, ebt_check_match, e, name, hookmask, &i);
+	if (ret != 0)
+		goto cleanup_matches;
+	j = 0;
+	ret = EBT_WATCHER_ITERATE(e, ebt_check_watcher, e, name, hookmask, &j);
+	if (ret != 0)
+		goto cleanup_watchers;
+	t = (struct ebt_entry_target *)(((char *)e) + e->target_offset);
+	target = find_target_lock(t->u.name, &ret, &ebt_mutex);
+	if (!target)
+		goto cleanup_watchers;
+	if (target->me)
+		__MOD_INC_USE_COUNT(target->me);
+	up(&ebt_mutex);
+
+	t->u.target = target;
+	if (t->u.target == &ebt_standard_target) {
+		if (e->target_offset + sizeof(struct ebt_standard_target) >
+		   e->next_offset) {
+			BUGPRINT("Standard target size too big\n");
+			ret = -EFAULT;
+			goto cleanup_watchers;
+		}
+		if (((struct ebt_standard_target *)t)->verdict <
+		   -NUM_STANDARD_TARGETS) {
+			BUGPRINT("Invalid standard target\n");
+			ret = -EFAULT;
+			goto cleanup_watchers;
+		}
+	} else if ((e->target_offset + t->target_size +
+	   sizeof(struct ebt_entry_target) > e->next_offset) ||
+	   (t->u.target->check &&
+	   t->u.target->check(name, hookmask, e, t->data, t->target_size) != 0)){
+		if (t->u.target->me)
+			__MOD_DEC_USE_COUNT(t->u.target->me);
+		ret = -EFAULT;
+		goto cleanup_watchers;
+	}
+	(*cnt)++;
+	return 0;
+cleanup_watchers:
+	EBT_WATCHER_ITERATE(e, ebt_cleanup_watcher, &j);
+cleanup_matches:
+	EBT_MATCH_ITERATE(e, ebt_cleanup_match, &i);
+	return ret;
+}
+
+// checks for loops and sets the hook mask for udc
+// the hook mask for udc tells us from which base chains the udc can be
+// accessed. This mask is a parameter to the check() functions of the extensions
+static int check_chainloops(struct ebt_entries *chain,
+   struct ebt_cl_stack *cl_s, unsigned int udc_cnt, 
+   unsigned int hooknr, char *base)
+{
+	int i, chain_nr = -1, pos = 0, nentries = chain->nentries, verdict;
+	struct ebt_entry *e = (struct ebt_entry *)chain->data;
+	struct ebt_entry_target *t;
+
+	while (pos < nentries || chain_nr != -1) {
+		// end of udc, go back one 'recursion' step
+		if (pos == nentries) {
+			// put back values of the time when this chain was called
+			e = cl_s[chain_nr].cs.e;
+			if (cl_s[chain_nr].from != -1)
+				nentries =
+				cl_s[cl_s[chain_nr].from].cs.chaininfo->nentries;
+			else
+				nentries = chain->nentries;
+			pos = cl_s[chain_nr].cs.n;
+			// make sure we won't see a loop that isn't one
+			cl_s[chain_nr].cs.n = 0;
+			chain_nr = cl_s[chain_nr].from;
+			if (pos == nentries)
+				continue;
+		}
+		t = (struct ebt_entry_target *)
+		   (((char *)e) + e->target_offset);
+		if (strcmp(t->u.name, EBT_STANDARD_TARGET))
+			goto letscontinue;
+		if (e->target_offset + sizeof(struct ebt_standard_target) >
+		   e->next_offset) {
+			BUGPRINT("Standard target size too big\n");
+			return -1;
+		}
+		verdict = ((struct ebt_standard_target *)t)->verdict;
+		if (verdict >= 0) { // jump to another chain
+			struct ebt_entries *hlp2 =
+			   (struct ebt_entries *)(base + verdict);
+			for (i = 0; i < udc_cnt; i++)
+				if (hlp2 == cl_s[i].cs.chaininfo)
+					break;
+			// bad destination or loop
+			if (i == udc_cnt) {
+				BUGPRINT("bad destination\n");
+				return -1;
+			}
+			if (cl_s[i].cs.n) {
+				BUGPRINT("loop\n");
+				return -1;
+			}
+			// this can't be 0, so the above test is correct
+			cl_s[i].cs.n = pos + 1;
+			pos = 0;
+			cl_s[i].cs.e = ((void *)e + e->next_offset);
+			e = (struct ebt_entry *)(hlp2->data);
+			nentries = hlp2->nentries;
+			cl_s[i].from = chain_nr;
+			chain_nr = i;
+			// this udc is accessible from the base chain for hooknr
+			cl_s[i].hookmask |= (1 << hooknr);
+			continue;
+		}
+letscontinue:
+		e = (void *)e + e->next_offset;
+		pos++;
+	}
+	return 0;
+}
+
+// do the parsing of the table/chains/entries/matches/watchers/targets, heh
+static int translate_table(struct ebt_replace *repl,
+   struct ebt_table_info *newinfo)
+{
+	unsigned int i, j, k, udc_cnt;
+	int ret;
+	struct ebt_cl_stack *cl_s = NULL; // used in the checking for chain loops
+
+	i = 0;
+	while (i < NF_BR_NUMHOOKS && !(repl->valid_hooks & (1 << i)))
+		i++;
+	if (i == NF_BR_NUMHOOKS) {
+		BUGPRINT("No valid hooks specified\n");
+		return -EINVAL;
+	}
+	if (repl->hook_entry[i] != (struct ebt_entries *)repl->entries) {
+		BUGPRINT("Chains don't start at beginning\n");
+		return -EINVAL;
+	}
+	// make sure chains are ordered after each other in same order
+	// as their corresponding hooks
+	for (j = i + 1; j < NF_BR_NUMHOOKS; j++) {
+		if (!(repl->valid_hooks & (1 << j)))
+			continue;
+		if ( repl->hook_entry[j] <= repl->hook_entry[i] ) {
+			BUGPRINT("Hook order must be followed\n");
+			return -EINVAL;
+		}
+		i = j;
+	}
+
+	for (i = 0; i < NF_BR_NUMHOOKS; i++)
+		newinfo->hook_entry[i] = NULL;
+
+	newinfo->entries_size = repl->entries_size;
+	newinfo->nentries = repl->nentries;
+
+	// do some early checkings and initialize some things
+	i = 0; // holds the expected nr. of entries for the chain
+	j = 0; // holds the up to now counted entries for the chain
+	k = 0; // holds the total nr. of entries, should equal
+	       // newinfo->nentries afterwards
+	udc_cnt = 0; // will hold the nr. of user defined chains (udc)
+	ret = EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size,
+	   ebt_check_entry_size_and_hooks, newinfo, repl->entries,
+	   repl->entries + repl->entries_size, repl->hook_entry, &i, &j, &k,
+	   &udc_cnt, repl->valid_hooks);
+
+	if (ret != 0)
+		return ret;
+
+	if (i != j) {
+		BUGPRINT("nentries does not equal the nr of entries in the "
+		         "(last) chain\n");
+		return -EINVAL;
+	}
+	if (k != newinfo->nentries) {
+		BUGPRINT("Total nentries is wrong\n");
+		return -EINVAL;
+	}
+
+	// check if all valid hooks have a chain
+	for (i = 0; i < NF_BR_NUMHOOKS; i++) {
+		if (newinfo->hook_entry[i] == NULL &&
+		   (repl->valid_hooks & (1 << i))) {
+			BUGPRINT("Valid hook without chain\n");
+			return -EINVAL;
+		}
+	}
+
+	// Get the location of the udc, put them in an array
+	// While we're at it, allocate the chainstack
+	if (udc_cnt) {
+		// this will get free'd in do_replace()/ebt_register_table()
+		// if an error occurs
+		newinfo->chainstack = (struct ebt_chainstack **)
+		   vmalloc(smp_num_cpus * sizeof(struct ebt_chainstack));
+		if (!newinfo->chainstack)
+			return -ENOMEM;
+		for (i = 0; i < smp_num_cpus; i++) {
+			newinfo->chainstack[i] =
+			   vmalloc(udc_cnt * sizeof(struct ebt_chainstack));
+			if (!newinfo->chainstack[i]) {
+				while (i)
+					vfree(newinfo->chainstack[--i]);
+				vfree(newinfo->chainstack);
+				newinfo->chainstack = NULL;
+				return -ENOMEM;
+			}
+		}
+
+		cl_s = (struct ebt_cl_stack *)
+		   vmalloc(udc_cnt * sizeof(struct ebt_cl_stack));
+		if (!cl_s)
+			return -ENOMEM;
+		i = 0; // the i'th udc
+		EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size,
+		   ebt_get_udc_positions, newinfo, repl->hook_entry, &i,
+		   repl->valid_hooks, cl_s);
+		// sanity check
+		if (i != udc_cnt) {
+			BUGPRINT("i != udc_cnt\n");
+			vfree(cl_s);
+			return -EFAULT;
+		}
+	}
+
+	// Check for loops
+	for (i = 0; i < NF_BR_NUMHOOKS; i++)
+		if (repl->valid_hooks & (1 << i))
+			if (check_chainloops(newinfo->hook_entry[i],
+			   cl_s, udc_cnt, i, newinfo->entries)) {
+				if (cl_s)
+					vfree(cl_s);
+				return -EINVAL;
+			}
+
+	// we now know the following (along with E=mc�):
+	// - the nr of entries in each chain is right
+	// - the size of the allocated space is right
+	// - all valid hooks have a corresponding chain
+	// - there are no loops
+	// - wrong data can still be on the level of a single entry
+	// - could be there are jumps to places that are not the
+	//   beginning of a chain. This can only occur in chains that
+	//   are not accessible from any base chains, so we don't care.
+
+	// used to know what we need to clean up if something goes wrong
+	i = 0;
+	ret = EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size,
+	   ebt_check_entry, newinfo, repl->name, &i, repl->valid_hooks,
+	   cl_s, udc_cnt);
+	if (ret != 0) {
+		EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size,
+		   ebt_cleanup_entry, &i);
+	}
+	if (cl_s)
+		vfree(cl_s);
+	return ret;
+}
+
+// called under write_lock
+static void get_counters(struct ebt_counter *oldcounters,
+   struct ebt_counter *counters, unsigned int nentries)
+{
+	int i, cpu;
+	struct ebt_counter *counter_base;
+
+	// counters of cpu 0
+	memcpy(counters, oldcounters,
+	   sizeof(struct ebt_counter) * nentries);
+	// add other counters to those of cpu 0
+	for (cpu = 1; cpu < smp_num_cpus; cpu++) {
+		counter_base = COUNTER_BASE(oldcounters, nentries, cpu);
+		for (i = 0; i < nentries; i++) {
+			counters[i].pcnt += counter_base[i].pcnt;
+			counters[i].bcnt += counter_base[i].bcnt;
+		}
+	}
+}
+
+// replace the table
+static int do_replace(void *user, unsigned int len)
+{
+	int ret, i, countersize;
+	struct ebt_table_info *newinfo;
+	struct ebt_replace tmp;
+	struct ebt_table *t;
+	struct ebt_counter *counterstmp = NULL;
+	// used to be able to unlock earlier
+	struct ebt_table_info *table;
+
+	if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
+		return -EFAULT;
+
+	if (len != sizeof(tmp) + tmp.entries_size) {
+		BUGPRINT("Wrong len argument\n");
+		return -EINVAL;
+	}
+
+	if (tmp.entries_size == 0) {
+		BUGPRINT("Entries_size never zero\n");
+		return -EINVAL;
+	}
+	countersize = COUNTER_OFFSET(tmp.nentries) * smp_num_cpus;
+	newinfo = (struct ebt_table_info *)
+	   vmalloc(sizeof(struct ebt_table_info) + countersize);
+	if (!newinfo)
+		return -ENOMEM;
+
+	if (countersize)
+		memset(newinfo->counters, 0, countersize);
+
+	newinfo->entries = (char *)vmalloc(tmp.entries_size);
+	if (!newinfo->entries) {
+		ret = -ENOMEM;
+		goto free_newinfo;
+	}
+	if (copy_from_user(
+	   newinfo->entries, tmp.entries, tmp.entries_size) != 0) {
+		BUGPRINT("Couldn't copy entries from userspace\n");
+		ret = -EFAULT;
+		goto free_entries;
+	}
+
+	// the user wants counters back
+	// the check on the size is done later, when we have the lock
+	if (tmp.num_counters) {
+		counterstmp = (struct ebt_counter *)
+		   vmalloc(tmp.num_counters * sizeof(struct ebt_counter));
+		if (!counterstmp) {
+			ret = -ENOMEM;
+			goto free_entries;
+		}
+	}
+	else
+		counterstmp = NULL;
+
+	// this can get initialized by translate_table()
+	newinfo->chainstack = NULL;
+	ret = translate_table(&tmp, newinfo);
+
+	if (ret != 0)
+		goto free_counterstmp;
+
+	t = find_table_lock(tmp.name, &ret, &ebt_mutex);
+	if (!t)
+		goto free_iterate;
+
+	// the table doesn't like it
+	if (t->check && (ret = t->check(newinfo, tmp.valid_hooks)))
+		goto free_unlock;
+
+	if (tmp.num_counters && tmp.num_counters != t->private->nentries) {
+		BUGPRINT("Wrong nr. of counters requested\n");
+		ret = -EINVAL;
+		goto free_unlock;
+	}
+
+	// we have the mutex lock, so no danger in reading this pointer
+	table = t->private;
+	// we need an atomic snapshot of the counters
+	write_lock_bh(&t->lock);
+	if (tmp.num_counters)
+		get_counters(t->private->counters, counterstmp,
+		   t->private->nentries);
+
+	t->private = newinfo;
+	write_unlock_bh(&t->lock);
+	up(&ebt_mutex);
+	// So, a user can change the chains while having messed up her counter
+	// allocation. Only reason why this is done is because this way the lock
+	// is held only once, while this doesn't bring the kernel into a
+	// dangerous state.
+	if (tmp.num_counters &&
+	   copy_to_user(tmp.counters, counterstmp,
+	   tmp.num_counters * sizeof(struct ebt_counter))) {
+		BUGPRINT("Couldn't copy counters to userspace\n");
+		ret = -EFAULT;
+	}
+	else
+		ret = 0;
+
+	// decrease module count and free resources
+	EBT_ENTRY_ITERATE(table->entries, table->entries_size,
+	   ebt_cleanup_entry, NULL);
+
+	vfree(table->entries);
+	if (table->chainstack) {
+		for (i = 0; i < smp_num_cpus; i++)
+			vfree(table->chainstack[i]);
+		vfree(table->chainstack);
+	}
+	vfree(table);
+
+	if (counterstmp)
+		vfree(counterstmp);
+	return ret;
+
+free_unlock:
+	up(&ebt_mutex);
+free_iterate:
+	EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size,
+	   ebt_cleanup_entry, NULL);
+free_counterstmp:
+	if (counterstmp)
+		vfree(counterstmp);
+	// can be initialized in translate_table()
+	if (newinfo->chainstack) {
+		for (i = 0; i < smp_num_cpus; i++)
+			vfree(newinfo->chainstack[i]);
+		vfree(newinfo->chainstack);
+	}
+free_entries:
+	if (newinfo->entries)
+		vfree(newinfo->entries);
+free_newinfo:
+	if (newinfo)
+		vfree(newinfo);
+	return ret;
+}
+
+int ebt_register_target(struct ebt_target *target)
+{
+	int ret;
+
+	ret = down_interruptible(&ebt_mutex);
+	if (ret != 0)
+		return ret;
+	if (!list_named_insert(&ebt_targets, target)) {
+		up(&ebt_mutex);
+		return -EEXIST;
+	}
+	up(&ebt_mutex);
+	MOD_INC_USE_COUNT;
+
+	return 0;
+}
+
+void ebt_unregister_target(struct ebt_target *target)
+{
+	down(&ebt_mutex);
+	LIST_DELETE(&ebt_targets, target);
+	up(&ebt_mutex);
+	MOD_DEC_USE_COUNT;
+}
+
+int ebt_register_match(struct ebt_match *match)
+{
+	int ret;
+
+	ret = down_interruptible(&ebt_mutex);
+	if (ret != 0)
+		return ret;
+	if (!list_named_insert(&ebt_matches, match)) {
+		up(&ebt_mutex);
+		return -EEXIST;
+	}
+	up(&ebt_mutex);
+	MOD_INC_USE_COUNT;
+
+	return 0;
+}
+
+void ebt_unregister_match(struct ebt_match *match)
+{
+	down(&ebt_mutex);
+	LIST_DELETE(&ebt_matches, match);
+	up(&ebt_mutex);
+	MOD_DEC_USE_COUNT;
+}
+
+int ebt_register_watcher(struct ebt_watcher *watcher)
+{
+	int ret;
+
+	ret = down_interruptible(&ebt_mutex);
+	if (ret != 0)
+		return ret;
+	if (!list_named_insert(&ebt_watchers, watcher)) {
+		up(&ebt_mutex);
+		return -EEXIST;
+	}
+	up(&ebt_mutex);
+	MOD_INC_USE_COUNT;
+
+	return 0;
+}
+
+void ebt_unregister_watcher(struct ebt_watcher *watcher)
+{
+	down(&ebt_mutex);
+	LIST_DELETE(&ebt_watchers, watcher);
+	up(&ebt_mutex);
+	MOD_DEC_USE_COUNT;
+}
+
+int ebt_register_table(struct ebt_table *table)
+{
+	struct ebt_table_info *newinfo;
+	int ret, i, countersize;
+
+	if (!table || !table->table ||!table->table->entries ||
+	    table->table->entries_size == 0 ||
+	    table->table->counters || table->private) {
+		BUGPRINT("Bad table data for ebt_register_table!!!\n");
+		return -EINVAL;
+	}
+
+	countersize = COUNTER_OFFSET(table->table->nentries) * smp_num_cpus;
+	newinfo = (struct ebt_table_info *)
+	   vmalloc(sizeof(struct ebt_table_info) + countersize);
+	ret = -ENOMEM;
+	if (!newinfo)
+		return -ENOMEM;
+
+	newinfo->entries = (char *)vmalloc(table->table->entries_size);
+	if (!(newinfo->entries))
+		goto free_newinfo;
+
+	memcpy(newinfo->entries, table->table->entries,
+	   table->table->entries_size);
+
+	if (countersize)
+		memset(newinfo->counters, 0, countersize);
+
+	// fill in newinfo and parse the entries
+	newinfo->chainstack = NULL;
+	ret = translate_table(table->table, newinfo);
+	if (ret != 0) {
+		BUGPRINT("Translate_table failed\n");
+		goto free_chainstack;
+	}
+
+	if (table->check && table->check(newinfo, table->valid_hooks)) {
+		BUGPRINT("The table doesn't like its own initial data, lol\n");
+		return -EINVAL;
+	}
+
+	table->private = newinfo;
+	table->lock = RW_LOCK_UNLOCKED;
+	ret = down_interruptible(&ebt_mutex);
+	if (ret != 0)
+		goto free_chainstack;
+
+	if (list_named_find(&ebt_tables, table->name)) {
+		ret = -EEXIST;
+		BUGPRINT("Table name already exists\n");
+		goto free_unlock;
+	}
+
+	list_prepend(&ebt_tables, table);
+	up(&ebt_mutex);
+	MOD_INC_USE_COUNT;
+	return 0;
+free_unlock:
+	up(&ebt_mutex);
+free_chainstack:
+	if (newinfo->chainstack) {
+		for (i = 0; i < smp_num_cpus; i++)
+			vfree(newinfo->chainstack[i]);
+		vfree(newinfo->chainstack);
+	}
+	vfree(newinfo->entries);
+free_newinfo:
+	vfree(newinfo);
+	return ret;
+}
+
+void ebt_unregister_table(struct ebt_table *table)
+{
+	int i;
+
+	if (!table) {
+		BUGPRINT("Request to unregister NULL table!!!\n");
+		return;
+	}
+	down(&ebt_mutex);
+	LIST_DELETE(&ebt_tables, table);
+	up(&ebt_mutex);
+	EBT_ENTRY_ITERATE(table->private->entries,
+	   table->private->entries_size, ebt_cleanup_entry, NULL);
+	if (table->private->entries)
+		vfree(table->private->entries);
+	if (table->private->chainstack) {
+		for (i = 0; i < smp_num_cpus; i++)
+			vfree(table->private->chainstack[i]);
+		vfree(table->private->chainstack);
+	}
+	vfree(table->private);
+	MOD_DEC_USE_COUNT;
+}
+
+// userspace just supplied us with counters
+static int update_counters(void *user, unsigned int len)
+{
+	int i, ret;
+	struct ebt_counter *tmp;
+	struct ebt_replace hlp;
+	struct ebt_table *t;
+
+	if (copy_from_user(&hlp, user, sizeof(hlp)))
+		return -EFAULT;
+
+	if (len != sizeof(hlp) + hlp.num_counters * sizeof(struct ebt_counter))
+		return -EINVAL;
+	if (hlp.num_counters == 0)
+		return -EINVAL;
+
+	if ( !(tmp = (struct ebt_counter *)
+	   vmalloc(hlp.num_counters * sizeof(struct ebt_counter))) ){
+		MEMPRINT("Update_counters && nomemory\n");
+		return -ENOMEM;
+	}
+
+	t = find_table_lock(hlp.name, &ret, &ebt_mutex);
+	if (!t)
+		goto free_tmp;
+
+	if (hlp.num_counters != t->private->nentries) {
+		BUGPRINT("Wrong nr of counters\n");
+		ret = -EINVAL;
+		goto unlock_mutex;
+	}
+
+	if ( copy_from_user(tmp, hlp.counters,
+	   hlp.num_counters * sizeof(struct ebt_counter)) ) {
+		BUGPRINT("Updata_counters && !cfu\n");
+		ret = -EFAULT;
+		goto unlock_mutex;
+	}
+
+	// we want an atomic add of the counters
+	write_lock_bh(&t->lock);
+
+	// we add to the counters of the first cpu
+	for (i = 0; i < hlp.num_counters; i++) {
+		t->private->counters[i].pcnt += tmp[i].pcnt;
+		t->private->counters[i].bcnt += tmp[i].bcnt;
+	}
+
+	write_unlock_bh(&t->lock);
+	ret = 0;
+unlock_mutex:
+	up(&ebt_mutex);
+free_tmp:
+	vfree(tmp);
+	return ret;
+}
+
+static inline int ebt_make_matchname(struct ebt_entry_match *m,
+   char *base, char *ubase)
+{
+	char *hlp = ubase - base + (char *)m;
+	if (copy_to_user(hlp, m->u.match->name, EBT_FUNCTION_MAXNAMELEN))
+		return -EFAULT;
+	return 0;
+}
+
+static inline int ebt_make_watchername(struct ebt_entry_watcher *w,
+   char *base, char *ubase)
+{
+	char *hlp = ubase - base + (char *)w;
+	if (copy_to_user(hlp , w->u.watcher->name, EBT_FUNCTION_MAXNAMELEN))
+		return -EFAULT;
+	return 0;
+}
+
+static inline int ebt_make_names(struct ebt_entry *e, char *base, char *ubase)
+{
+	int ret;
+	char *hlp;
+	struct ebt_entry_target *t;
+
+	if ((e->bitmask & EBT_ENTRY_OR_ENTRIES) == 0)
+		return 0;
+
+	hlp = ubase - base + (char *)e + e->target_offset;
+	t = (struct ebt_entry_target *)(((char *)e) + e->target_offset);
+	
+	ret = EBT_MATCH_ITERATE(e, ebt_make_matchname, base, ubase);
+	if (ret != 0)
+		return ret;
+	ret = EBT_WATCHER_ITERATE(e, ebt_make_watchername, base, ubase);
+	if (ret != 0)
+		return ret;
+	if (copy_to_user(hlp, t->u.target->name, EBT_FUNCTION_MAXNAMELEN))
+		return -EFAULT;
+	return 0;
+}
+
+// called with ebt_mutex down
+static int copy_everything_to_user(struct ebt_table *t, void *user,
+   int *len, int cmd)
+{
+	struct ebt_replace tmp;
+	struct ebt_counter *counterstmp, *oldcounters;
+	unsigned int entries_size, nentries;
+	char *entries;
+
+	if (cmd == EBT_SO_GET_ENTRIES) {
+		entries_size = t->private->entries_size;
+		nentries = t->private->nentries;
+		entries = t->private->entries;
+		oldcounters = t->private->counters;
+	} else {
+		entries_size = t->table->entries_size;
+		nentries = t->table->nentries;
+		entries = t->table->entries;
+		oldcounters = t->table->counters;
+	}
+
+	if (copy_from_user(&tmp, user, sizeof(tmp))) {
+		BUGPRINT("Cfu didn't work\n");
+		return -EFAULT;
+	}
+
+	if (*len != sizeof(struct ebt_replace) + entries_size +
+	   (tmp.num_counters? nentries * sizeof(struct ebt_counter): 0)) {
+		BUGPRINT("Wrong size\n");
+		return -EINVAL;
+	}
+
+	if (tmp.nentries != nentries) {
+		BUGPRINT("Nentries wrong\n");
+		return -EINVAL;
+	}
+
+	if (tmp.entries_size != entries_size) {
+		BUGPRINT("Wrong size\n");
+		return -EINVAL;
+	}
+
+	// userspace might not need the counters
+	if (tmp.num_counters) {
+		if (tmp.num_counters != nentries) {
+			BUGPRINT("Num_counters wrong\n");
+			return -EINVAL;
+		}
+		counterstmp = (struct ebt_counter *)
+		   vmalloc(nentries * sizeof(struct ebt_counter));
+		if (!counterstmp) {
+			MEMPRINT("Couldn't copy counters, out of memory\n");
+			return -ENOMEM;
+		}
+		write_lock_bh(&t->lock);
+		get_counters(oldcounters, counterstmp, nentries);
+		write_unlock_bh(&t->lock);
+
+		if (copy_to_user(tmp.counters, counterstmp,
+		   nentries * sizeof(struct ebt_counter))) {
+			BUGPRINT("Couldn't copy counters to userspace\n");
+			vfree(counterstmp);
+			return -EFAULT;
+		}
+		vfree(counterstmp);
+	}
+
+	if (copy_to_user(tmp.entries, entries, entries_size)) {
+		BUGPRINT("Couldn't copy entries to userspace\n");
+		return -EFAULT;
+	}
+	// set the match/watcher/target names right
+	return EBT_ENTRY_ITERATE(entries, entries_size,
+	   ebt_make_names, entries, tmp.entries);
+}
+
+static int do_ebt_set_ctl(struct sock *sk,
+	int cmd, void *user, unsigned int len)
+{
+	int ret;
+
+	switch(cmd) {
+	case EBT_SO_SET_ENTRIES:
+		ret = do_replace(user, len);
+		break;
+	case EBT_SO_SET_COUNTERS:
+		ret = update_counters(user, len);
+		break;
+	default:
+		ret = -EINVAL;
+  }
+	return ret;
+}
+
+static int do_ebt_get_ctl(struct sock *sk, int cmd, void *user, int *len)
+{
+	int ret;
+	struct ebt_replace tmp;
+	struct ebt_table *t;
+
+	if (copy_from_user(&tmp, user, sizeof(tmp)))
+		return -EFAULT;
+
+	t = find_table_lock(tmp.name, &ret, &ebt_mutex);
+	if (!t)
+		return ret;
+
+	switch(cmd) {
+	case EBT_SO_GET_INFO:
+	case EBT_SO_GET_INIT_INFO:
+		if (*len != sizeof(struct ebt_replace)){
+			ret = -EINVAL;
+			up(&ebt_mutex);
+			break;
+		}
+		if (cmd == EBT_SO_GET_INFO) {
+			tmp.nentries = t->private->nentries;
+			tmp.entries_size = t->private->entries_size;
+			tmp.valid_hooks = t->valid_hooks;
+		} else {
+			tmp.nentries = t->table->nentries;
+			tmp.entries_size = t->table->entries_size;
+			tmp.valid_hooks = t->table->valid_hooks;
+		}
+		up(&ebt_mutex);
+		if (copy_to_user(user, &tmp, *len) != 0){
+			BUGPRINT("c2u Didn't work\n");
+			ret = -EFAULT;
+			break;
+		}
+		ret = 0;
+		break;
+
+	case EBT_SO_GET_ENTRIES:
+	case EBT_SO_GET_INIT_ENTRIES:
+		ret = copy_everything_to_user(t, user, len, cmd);
+		up(&ebt_mutex);
+		break;
+
+	default:
+		up(&ebt_mutex);
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static struct nf_sockopt_ops ebt_sockopts =
+{ { NULL, NULL }, PF_INET, EBT_BASE_CTL, EBT_SO_SET_MAX + 1, do_ebt_set_ctl,
+    EBT_BASE_CTL, EBT_SO_GET_MAX + 1, do_ebt_get_ctl, 0, NULL
+};
+
+static int __init init(void)
+{
+	int ret;
+
+	down(&ebt_mutex);
+	list_named_insert(&ebt_targets, &ebt_standard_target);
+	up(&ebt_mutex);
+	if ((ret = nf_register_sockopt(&ebt_sockopts)) < 0)
+		return ret;
+
+	printk(KERN_NOTICE "Ebtables v2.0 registered\n");
+	return 0;
+}
+
+static void __exit fini(void)
+{
+	nf_unregister_sockopt(&ebt_sockopts);
+	printk(KERN_NOTICE "Ebtables v2.0 unregistered\n");
+}
+
+EXPORT_SYMBOL(ebt_register_table);
+EXPORT_SYMBOL(ebt_unregister_table);
+EXPORT_SYMBOL(ebt_register_match);
+EXPORT_SYMBOL(ebt_unregister_match);
+EXPORT_SYMBOL(ebt_register_watcher);
+EXPORT_SYMBOL(ebt_unregister_watcher);
+EXPORT_SYMBOL(ebt_register_target);
+EXPORT_SYMBOL(ebt_unregister_target);
+EXPORT_SYMBOL(ebt_do_table);
+module_init(init);
+module_exit(fini);
+MODULE_LICENSE("GPL");
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/include/linux/netfilter_bridge/ebtables.h	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,361 @@
+/*
+ *  ebtables
+ *
+ *	Authors:
+ *	Bart De Schuymer		<bart.de.schuymer@pandora.be>
+ *
+ *  ebtables.c,v 2.0, September, 2002
+ *
+ *  This code is stongly inspired on the iptables code which is
+ *  Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
+ */
+
+#ifndef __LINUX_BRIDGE_EFF_H
+#define __LINUX_BRIDGE_EFF_H
+#include <linux/if.h>
+#include <linux/netfilter_bridge.h>
+#include <linux/if_ether.h>
+
+#define EBT_TABLE_MAXNAMELEN 32
+#define EBT_CHAIN_MAXNAMELEN EBT_TABLE_MAXNAMELEN
+#define EBT_FUNCTION_MAXNAMELEN EBT_TABLE_MAXNAMELEN
+
+// verdicts >0 are "branches"
+#define EBT_ACCEPT   -1
+#define EBT_DROP     -2
+#define EBT_CONTINUE -3
+#define EBT_RETURN   -4
+#define NUM_STANDARD_TARGETS   4
+
+struct ebt_replace
+{
+	char name[EBT_TABLE_MAXNAMELEN];
+	unsigned int valid_hooks;
+	// nr of rules in the table
+	unsigned int nentries;
+	// total size of the entries
+	unsigned int entries_size;
+	// start of the chains
+	struct ebt_entries *hook_entry[NF_BR_NUMHOOKS];
+	// nr of counters userspace expects back
+	unsigned int num_counters;
+	// where the kernel will put the old counters
+	struct ebt_counter *counters;
+	char *entries;
+};
+
+struct ebt_counter
+{
+	uint64_t pcnt;
+	uint64_t bcnt;
+};
+
+struct ebt_entries {
+	// this field is always set to zero
+	// See EBT_ENTRY_OR_ENTRIES.
+	// Must be same size as ebt_entry.bitmask
+	unsigned int distinguisher;
+	// the chain name
+	char name[EBT_CHAIN_MAXNAMELEN];
+	// counter offset for this chain
+	unsigned int counter_offset;
+	// one standard (accept, drop, return) per hook
+	int policy;
+	// nr. of entries
+	unsigned int nentries;
+	// entry list
+	char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
+};
+
+// used for the bitmask of struct ebt_entry
+
+// This is a hack to make a difference between an ebt_entry struct and an
+// ebt_entries struct when traversing the entries from start to end.
+// Using this simplifies the code alot, while still being able to use
+// ebt_entries.
+// Contrary, iptables doesn't use something like ebt_entries and therefore uses
+// different techniques for naming the policy and such. So, iptables doesn't
+// need a hack like this.
+#define EBT_ENTRY_OR_ENTRIES 0x01
+// these are the normal masks
+#define EBT_NOPROTO 0x02
+#define EBT_802_3 0x04
+#define EBT_SOURCEMAC 0x08
+#define EBT_DESTMAC 0x10
+#define EBT_F_MASK (EBT_NOPROTO | EBT_802_3 | EBT_SOURCEMAC | EBT_DESTMAC \
+   | EBT_ENTRY_OR_ENTRIES)
+
+#define EBT_IPROTO 0x01
+#define EBT_IIN 0x02
+#define EBT_IOUT 0x04
+#define EBT_ISOURCE 0x8
+#define EBT_IDEST 0x10
+#define EBT_ILOGICALIN 0x20
+#define EBT_ILOGICALOUT 0x40
+#define EBT_INV_MASK (EBT_IPROTO | EBT_IIN | EBT_IOUT | EBT_ILOGICALIN \
+   | EBT_ILOGICALOUT | EBT_ISOURCE | EBT_IDEST)
+
+struct ebt_entry_match
+{
+	union {
+		char name[EBT_FUNCTION_MAXNAMELEN];
+		struct ebt_match *match;
+	} u;
+	// size of data
+	unsigned int match_size;
+	unsigned char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
+};
+
+struct ebt_entry_watcher
+{
+	union {
+		char name[EBT_FUNCTION_MAXNAMELEN];
+		struct ebt_watcher *watcher;
+	} u;
+	// size of data
+	unsigned int watcher_size;
+	unsigned char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
+};
+
+struct ebt_entry_target
+{
+	union {
+		char name[EBT_FUNCTION_MAXNAMELEN];
+		struct ebt_target *target;
+	} u;
+	// size of data
+	unsigned int target_size;
+	unsigned char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
+};
+
+#define EBT_STANDARD_TARGET "standard"
+struct ebt_standard_target
+{
+	struct ebt_entry_target target;
+	int verdict;
+};
+
+// one entry
+struct ebt_entry {
+	// this needs to be the first field
+	unsigned int bitmask;
+	unsigned int invflags;
+	uint16_t ethproto;
+	// the physical in-dev
+	char in[IFNAMSIZ];
+	// the logical in-dev
+	char logical_in[IFNAMSIZ];
+	// the physical out-dev
+	char out[IFNAMSIZ];
+	// the logical out-dev
+	char logical_out[IFNAMSIZ];
+	unsigned char sourcemac[ETH_ALEN];
+	unsigned char sourcemsk[ETH_ALEN];
+	unsigned char destmac[ETH_ALEN];
+	unsigned char destmsk[ETH_ALEN];
+	// sizeof ebt_entry + matches
+	unsigned int watchers_offset;
+	// sizeof ebt_entry + matches + watchers
+	unsigned int target_offset;
+	// sizeof ebt_entry + matches + watchers + target
+	unsigned int next_offset;
+	unsigned char elems[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
+};
+
+// [gs]etsockopt numbers
+#define EBT_BASE_CTL            128
+
+#define EBT_SO_SET_ENTRIES      (EBT_BASE_CTL)
+#define EBT_SO_SET_COUNTERS     (EBT_SO_SET_ENTRIES+1)
+#define EBT_SO_SET_MAX          (EBT_SO_SET_COUNTERS+1)
+
+#define EBT_SO_GET_INFO         (EBT_BASE_CTL)
+#define EBT_SO_GET_ENTRIES      (EBT_SO_GET_INFO+1)
+#define EBT_SO_GET_INIT_INFO    (EBT_SO_GET_ENTRIES+1)
+#define EBT_SO_GET_INIT_ENTRIES (EBT_SO_GET_INIT_INFO+1)
+#define EBT_SO_GET_MAX          (EBT_SO_GET_INIT_ENTRIES+1)
+
+#ifdef __KERNEL__
+
+// return values for match() functions
+#define EBT_MATCH 0
+#define EBT_NOMATCH 1
+
+struct ebt_match
+{
+	struct list_head list;
+	const char name[EBT_FUNCTION_MAXNAMELEN];
+	// 0 == it matches
+	int (*match)(const struct sk_buff *skb, const struct net_device *in,
+	   const struct net_device *out, const void *matchdata,
+	   unsigned int datalen);
+	// 0 == let it in
+	int (*check)(const char *tablename, unsigned int hookmask,
+	   const struct ebt_entry *e, void *matchdata, unsigned int datalen);
+	void (*destroy)(void *matchdata, unsigned int datalen);
+	struct module *me;
+};
+
+struct ebt_watcher
+{
+	struct list_head list;
+	const char name[EBT_FUNCTION_MAXNAMELEN];
+	void (*watcher)(const struct sk_buff *skb, const struct net_device *in,
+	   const struct net_device *out, const void *watcherdata,
+	   unsigned int datalen);
+	// 0 == let it in
+	int (*check)(const char *tablename, unsigned int hookmask,
+	   const struct ebt_entry *e, void *watcherdata, unsigned int datalen);
+	void (*destroy)(void *watcherdata, unsigned int datalen);
+	struct module *me;
+};
+
+struct ebt_target
+{
+	struct list_head list;
+	const char name[EBT_FUNCTION_MAXNAMELEN];
+	// returns one of the standard verdicts
+	int (*target)(struct sk_buff **pskb, unsigned int hooknr,
+	   const struct net_device *in, const struct net_device *out,
+	   const void *targetdata, unsigned int datalen);
+	// 0 == let it in
+	int (*check)(const char *tablename, unsigned int hookmask,
+	   const struct ebt_entry *e, void *targetdata, unsigned int datalen);
+	void (*destroy)(void *targetdata, unsigned int datalen);
+	struct module *me;
+};
+
+// used for jumping from and into user defined chains (udc)
+struct ebt_chainstack
+{
+	struct ebt_entries *chaininfo; // pointer to chain data
+	struct ebt_entry *e; // pointer to entry data
+	unsigned int n; // n'th entry
+};
+
+struct ebt_table_info
+{
+	// total size of the entries
+	unsigned int entries_size;
+	unsigned int nentries;
+	// pointers to the start of the chains
+	struct ebt_entries *hook_entry[NF_BR_NUMHOOKS];
+	// room to maintain the stack used for jumping from and into udc
+	struct ebt_chainstack **chainstack;
+	char *entries;
+	struct ebt_counter counters[0] ____cacheline_aligned;
+};
+
+struct ebt_table
+{
+	struct list_head list;
+	char name[EBT_TABLE_MAXNAMELEN];
+	struct ebt_replace *table;
+	unsigned int valid_hooks;
+	rwlock_t lock;
+	// e.g. could be the table explicitly only allows certain
+	// matches, targets, ... 0 == let it in
+	int (*check)(const struct ebt_table_info *info,
+	   unsigned int valid_hooks);
+	// the data used by the kernel
+	struct ebt_table_info *private;
+};
+
+#define EBT_ALIGN(s) (((s) + (__alignof__(struct ebt_replace)-1)) & \
+		     ~(__alignof__(struct ebt_replace)-1))
+extern int ebt_register_table(struct ebt_table *table);
+extern void ebt_unregister_table(struct ebt_table *table);
+extern int ebt_register_match(struct ebt_match *match);
+extern void ebt_unregister_match(struct ebt_match *match);
+extern int ebt_register_watcher(struct ebt_watcher *watcher);
+extern void ebt_unregister_watcher(struct ebt_watcher *watcher);
+extern int ebt_register_target(struct ebt_target *target);
+extern void ebt_unregister_target(struct ebt_target *target);
+extern unsigned int ebt_do_table(unsigned int hook, struct sk_buff **pskb,
+   const struct net_device *in, const struct net_device *out,
+   struct ebt_table *table);
+
+   // Used in the kernel match() functions
+#define FWINV(bool,invflg) ((bool) ^ !!(info->invflags & invflg))
+// True if the hook mask denotes that the rule is in a base chain,
+// used in the check() functions
+#define BASE_CHAIN (hookmask & (1 << NF_BR_NUMHOOKS))
+// Clear the bit in the hook mask that tells if the rule is on a base chain
+#define CLEAR_BASE_CHAIN_BIT (hookmask &= ~(1 << NF_BR_NUMHOOKS))
+// True if the target is not a standard target
+#define INVALID_TARGET (info->target < -NUM_STANDARD_TARGETS || info->target >= 0)
+
+#endif /* __KERNEL__ */
+
+// blatently stolen from ip_tables.h
+// fn returns 0 to continue iteration
+#define EBT_MATCH_ITERATE(e, fn, args...)                   \
+({                                                          \
+	unsigned int __i;                                   \
+	int __ret = 0;                                      \
+	struct ebt_entry_match *__match;                    \
+	                                                    \
+	for (__i = sizeof(struct ebt_entry);                \
+	     __i < (e)->watchers_offset;                    \
+	     __i += __match->match_size +                   \
+	     sizeof(struct ebt_entry_match)) {              \
+		__match = (void *)(e) + __i;                \
+		                                            \
+		__ret = fn(__match , ## args);              \
+		if (__ret != 0)                             \
+			break;                              \
+	}                                                   \
+	if (__ret == 0) {                                   \
+		if (__i != (e)->watchers_offset)            \
+			__ret = -EINVAL;                    \
+	}                                                   \
+	__ret;                                              \
+})
+
+#define EBT_WATCHER_ITERATE(e, fn, args...)                 \
+({                                                          \
+	unsigned int __i;                                   \
+	int __ret = 0;                                      \
+	struct ebt_entry_watcher *__watcher;                \
+	                                                    \
+	for (__i = e->watchers_offset;                      \
+	     __i < (e)->target_offset;                      \
+	     __i += __watcher->watcher_size +               \
+	     sizeof(struct ebt_entry_watcher)) {            \
+		__watcher = (void *)(e) + __i;              \
+		                                            \
+		__ret = fn(__watcher , ## args);            \
+		if (__ret != 0)                             \
+			break;                              \
+	}                                                   \
+	if (__ret == 0) {                                   \
+		if (__i != (e)->target_offset)              \
+			__ret = -EINVAL;                    \
+	}                                                   \
+	__ret;                                              \
+})
+
+#define EBT_ENTRY_ITERATE(entries, size, fn, args...)       \
+({                                                          \
+	unsigned int __i;                                   \
+	int __ret = 0;                                      \
+	struct ebt_entry *__entry;                          \
+	                                                    \
+	for (__i = 0; __i < (size);) {                      \
+		__entry = (void *)(entries) + __i;          \
+		__ret = fn(__entry , ## args);              \
+		if (__ret != 0)                             \
+			break;                              \
+		if (__entry->bitmask != 0)                  \
+			__i += __entry->next_offset;        \
+		else                                        \
+			__i += sizeof(struct ebt_entries);  \
+	}                                                   \
+	if (__ret == 0) {                                   \
+		if (__i != (size))                          \
+			__ret = -EINVAL;                    \
+	}                                                   \
+	__ret;                                              \
+})
+
+#endif
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/include/linux/netfilter_bridge/ebt_802_3.h	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,60 @@
+#ifndef __LINUX_BRIDGE_EBT_802_3_H
+#define __LINUX_BRIDGE_EBT_802_3_H
+
+#define EBT_802_3_SAP 0x01
+#define EBT_802_3_TYPE 0x02
+
+#define EBT_802_3_MATCH "802_3"
+
+/*
+ * If frame has DSAP/SSAP value 0xaa you must check the SNAP type
+ * to discover what kind of packet we're carrying. 
+ */
+#define CHECK_TYPE 0xaa
+
+/*
+ * Control field may be one or two bytes.  If the first byte has
+ * the value 0x03 then the entire length is one byte, otherwise it is two.
+ * One byte controls are used in Unnumbered Information frames.
+ * Two byte controls are used in Numbered Information frames.
+ */
+#define IS_UI 0x03
+
+#define EBT_802_3_MASK (EBT_802_3_SAP | EBT_802_3_TYPE | EBT_802_3)
+
+/* ui has one byte ctrl, ni has two */
+struct hdr_ui {
+	uint8_t dsap;
+	uint8_t ssap;
+	uint8_t ctrl;
+	uint8_t orig[3];
+	uint16_t type;
+};
+
+struct hdr_ni {
+	uint8_t dsap;
+	uint8_t ssap;
+	uint16_t ctrl;
+	uint8_t  orig[3];
+	uint16_t type;
+};
+
+struct ebt_802_3_hdr {
+	uint8_t  daddr[6];
+	uint8_t  saddr[6];
+	uint16_t len;
+	union {
+		struct hdr_ui ui;
+		struct hdr_ni ni;
+	} llc;
+};
+
+struct ebt_802_3_info 
+{
+	uint8_t  sap;
+	uint16_t type;
+	uint8_t  bitmask;
+	uint8_t  invflags;
+};
+
+#endif
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/include/linux/netfilter_bridge/ebt_arp.h	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,32 @@
+#ifndef __LINUX_BRIDGE_EBT_ARP_H
+#define __LINUX_BRIDGE_EBT_ARP_H
+
+#define EBT_ARP_OPCODE 0x01
+#define EBT_ARP_HTYPE 0x02
+#define EBT_ARP_PTYPE 0x04
+#define EBT_ARP_SRC_IP 0x08
+#define EBT_ARP_DST_IP 0x10
+#define EBT_ARP_SRC_MAC 0x20
+#define EBT_ARP_DST_MAC 0x40
+#define EBT_ARP_MASK (EBT_ARP_OPCODE | EBT_ARP_HTYPE | EBT_ARP_PTYPE | \
+   EBT_ARP_SRC_IP | EBT_ARP_DST_IP | EBT_ARP_SRC_MAC | EBT_ARP_DST_MAC)
+#define EBT_ARP_MATCH "arp"
+
+struct ebt_arp_info
+{
+	uint16_t htype;
+	uint16_t ptype;
+	uint16_t opcode;
+	uint32_t saddr;
+	uint32_t smsk;
+	uint32_t daddr;
+	uint32_t dmsk;
+	unsigned char smaddr[ETH_ALEN];
+	unsigned char smmsk[ETH_ALEN];
+	unsigned char dmaddr[ETH_ALEN];
+	unsigned char dmmsk[ETH_ALEN];
+	uint8_t  bitmask;
+	uint8_t  invflags;
+};
+
+#endif
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/include/linux/netfilter_bridge/ebt_ip.h	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,43 @@
+/*
+ *  ebt_ip
+ *
+ *	Authors:
+ *	Bart De Schuymer <bart.de.schuymer@pandora.be>
+ *
+ *  April, 2002
+ *
+ *  Changes:
+ *    added ip-sport and ip-dport
+ *    Innominate Security Technologies AG <mhopf@innominate.com>
+ *    September, 2002
+ */
+
+#ifndef __LINUX_BRIDGE_EBT_IP_H
+#define __LINUX_BRIDGE_EBT_IP_H
+
+#define EBT_IP_SOURCE 0x01
+#define EBT_IP_DEST 0x02
+#define EBT_IP_TOS 0x04
+#define EBT_IP_PROTO 0x08
+#define EBT_IP_SPORT 0x10
+#define EBT_IP_DPORT 0x20
+#define EBT_IP_MASK (EBT_IP_SOURCE | EBT_IP_DEST | EBT_IP_TOS | EBT_IP_PROTO |\
+ EBT_IP_SPORT | EBT_IP_DPORT )
+#define EBT_IP_MATCH "ip"
+
+// the same values are used for the invflags
+struct ebt_ip_info
+{
+	uint32_t saddr;
+	uint32_t daddr;
+	uint32_t smsk;
+	uint32_t dmsk;
+	uint8_t  tos;
+	uint8_t  protocol;
+	uint8_t  bitmask;
+	uint8_t  invflags;
+	uint16_t sport[2];
+	uint16_t dport[2];
+};
+
+#endif
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/include/linux/netfilter_bridge/ebt_pkttype.h	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,11 @@
+#ifndef __LINUX_BRIDGE_EBT_PKTTYPE_H
+#define __LINUX_BRIDGE_EBT_PKTTYPE_H
+
+struct ebt_pkttype_info
+{
+	uint8_t pkt_type;
+	uint8_t invert;
+};
+#define EBT_PKTTYPE_MATCH "pkttype"
+
+#endif
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/include/linux/netfilter_bridge/ebt_stp.h	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,46 @@
+#ifndef __LINUX_BRIDGE_EBT_STP_H
+#define __LINUX_BRIDGE_EBT_STP_H
+
+#define EBT_STP_TYPE		0x0001
+
+#define EBT_STP_FLAGS		0x0002
+#define EBT_STP_ROOTPRIO	0x0004
+#define EBT_STP_ROOTADDR	0x0008
+#define EBT_STP_ROOTCOST	0x0010
+#define EBT_STP_SENDERPRIO	0x0020
+#define EBT_STP_SENDERADDR	0x0040
+#define EBT_STP_PORT		0x0080
+#define EBT_STP_MSGAGE		0x0100
+#define EBT_STP_MAXAGE		0x0200
+#define EBT_STP_HELLOTIME	0x0400
+#define EBT_STP_FWDD		0x0800
+
+#define EBT_STP_MASK		0x0fff
+#define EBT_STP_CONFIG_MASK	0x0ffe
+
+#define EBT_STP_MATCH "stp"
+
+struct ebt_stp_config_info
+{
+	uint8_t flags;
+	uint16_t root_priol, root_priou;
+	char root_addr[6], root_addrmsk[6];
+	uint32_t root_costl, root_costu;
+	uint16_t sender_priol, sender_priou;
+	char sender_addr[6], sender_addrmsk[6];
+	uint16_t portl, portu;
+	uint16_t msg_agel, msg_ageu;
+	uint16_t max_agel, max_ageu;
+	uint16_t hello_timel, hello_timeu;
+	uint16_t forward_delayl, forward_delayu;
+};
+
+struct ebt_stp_info
+{
+	uint8_t type;
+	struct ebt_stp_config_info config;
+	uint16_t bitmask;
+	uint16_t invflags;
+};
+
+#endif
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/include/linux/netfilter_bridge/ebt_vlan.h	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,20 @@
+#ifndef __LINUX_BRIDGE_EBT_VLAN_H
+#define __LINUX_BRIDGE_EBT_VLAN_H
+
+#define EBT_VLAN_ID	0x01
+#define EBT_VLAN_PRIO	0x02
+#define EBT_VLAN_ENCAP	0x04
+#define EBT_VLAN_MASK (EBT_VLAN_ID | EBT_VLAN_PRIO | EBT_VLAN_ENCAP)
+#define EBT_VLAN_MATCH "vlan"
+
+struct ebt_vlan_info {
+	uint16_t id;		/* VLAN ID {1-4095} */
+	uint8_t prio;		/* VLAN User Priority {0-7} */
+	uint16_t encap;		/* VLAN Encapsulated frame code {0-65535} */
+	uint8_t bitmask;		/* Args bitmask bit 1=1 - ID arg,
+				   bit 2=1 User-Priority arg, bit 3=1 encap*/
+	uint8_t invflags;		/* Inverse bitmask  bit 1=1 - inversed ID arg, 
+				   bit 2=1 - inversed Pirority arg */
+};
+
+#endif
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/include/linux/netfilter_bridge/ebt_log.h	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,17 @@
+#ifndef __LINUX_BRIDGE_EBT_LOG_H
+#define __LINUX_BRIDGE_EBT_LOG_H
+
+#define EBT_LOG_IP 0x01 // if the frame is made by ip, log the ip information
+#define EBT_LOG_ARP 0x02
+#define EBT_LOG_MASK (EBT_LOG_IP | EBT_LOG_ARP)
+#define EBT_LOG_PREFIX_SIZE 30
+#define EBT_LOG_WATCHER "log"
+
+struct ebt_log_info
+{
+	uint8_t loglevel;
+	uint8_t prefix[EBT_LOG_PREFIX_SIZE];
+	uint32_t bitmask;
+};
+
+#endif
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/include/linux/netfilter_bridge/ebt_nat.h	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,13 @@
+#ifndef __LINUX_BRIDGE_EBT_NAT_H
+#define __LINUX_BRIDGE_EBT_NAT_H
+
+struct ebt_nat_info
+{
+	unsigned char mac[ETH_ALEN];
+	// EBT_ACCEPT, EBT_DROP, EBT_CONTINUE or EBT_RETURN
+	int target;
+};
+#define EBT_SNAT_TARGET "snat"
+#define EBT_DNAT_TARGET "dnat"
+
+#endif
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/include/linux/netfilter_bridge/ebt_redirect.h	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,11 @@
+#ifndef __LINUX_BRIDGE_EBT_REDIRECT_H
+#define __LINUX_BRIDGE_EBT_REDIRECT_H
+
+struct ebt_redirect_info
+{
+	// EBT_ACCEPT, EBT_DROP or EBT_CONTINUE or EBT_RETURN
+	int target;
+};
+#define EBT_REDIRECT_TARGET "redirect"
+
+#endif
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/include/linux/netfilter_bridge/ebt_mark_m.h	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,15 @@
+#ifndef __LINUX_BRIDGE_EBT_MARK_M_H
+#define __LINUX_BRIDGE_EBT_MARK_M_H
+
+#define EBT_MARK_AND 0x01
+#define EBT_MARK_OR 0x02
+#define EBT_MARK_MASK (EBT_MARK_AND | EBT_MARK_OR)
+struct ebt_mark_m_info
+{
+	unsigned long mark, mask;
+	uint8_t invert;
+	uint8_t bitmask;
+};
+#define EBT_MARK_MATCH "mark_m"
+
+#endif
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/include/linux/netfilter_bridge/ebt_mark_t.h	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,12 @@
+#ifndef __LINUX_BRIDGE_EBT_MARK_T_H
+#define __LINUX_BRIDGE_EBT_MARK_T_H
+
+struct ebt_mark_t_info
+{
+	unsigned long mark;
+	// EBT_ACCEPT, EBT_DROP or EBT_CONTINUE or EBT_RETURN
+	int target;
+};
+#define EBT_MARK_TARGET "mark"
+
+#endif
--- linux-2.4.21/include/linux/netfilter.h	Thu Nov 22 20:47:48 2001
+++ linux-2.4.21-ebt-brnf-3/include/linux/netfilter.h	Fri Aug  8 01:09:06 2003
@@ -117,28 +117,34 @@ extern struct list_head nf_hooks[NPROTO]
 /* This is gross, but inline doesn't cut it for avoiding the function
    call in fast path: gcc doesn't inline (needs value tracking?). --RR */
 #ifdef CONFIG_NETFILTER_DEBUG
-#define NF_HOOK nf_hook_slow
+#define NF_HOOK(pf, hook, skb, indev, outdev, okfn)			\
+nf_hook_slow((pf), (hook), (skb), (indev), (outdev), (okfn), INT_MIN)
+#define NF_HOOK_THRESH nf_hook_slow
 #else
 #define NF_HOOK(pf, hook, skb, indev, outdev, okfn)			\
 (list_empty(&nf_hooks[(pf)][(hook)])					\
  ? (okfn)(skb)								\
- : nf_hook_slow((pf), (hook), (skb), (indev), (outdev), (okfn)))
+ : nf_hook_slow((pf), (hook), (skb), (indev), (outdev), (okfn), INT_MIN))
+#define NF_HOOK_THRESH(pf, hook, skb, indev, outdev, okfn, thresh)	\
+(list_empty(&nf_hooks[(pf)][(hook)])					\
+ ? (okfn)(skb)								\
+ : nf_hook_slow((pf), (hook), (skb), (indev), (outdev), (okfn), (thresh)))
 #endif
 
 int nf_hook_slow(int pf, unsigned int hook, struct sk_buff *skb,
 		 struct net_device *indev, struct net_device *outdev,
-		 int (*okfn)(struct sk_buff *));
+		 int (*okfn)(struct sk_buff *), int thresh);
 
 /* Call setsockopt() */
-int nf_setsockopt(struct sock *sk, int pf, int optval, char *opt, 
+int nf_setsockopt(struct sock *sk, int pf, int optval, char *opt,
 		  int len);
 int nf_getsockopt(struct sock *sk, int pf, int optval, char *opt,
 		  int *len);
 
 /* Packet queuing */
-typedef int (*nf_queue_outfn_t)(struct sk_buff *skb, 
+typedef int (*nf_queue_outfn_t)(struct sk_buff *skb,
                                 struct nf_info *info, void *data);
-extern int nf_register_queue_handler(int pf, 
+extern int nf_register_queue_handler(int pf,
                                      nf_queue_outfn_t outfn, void *data);
 extern int nf_unregister_queue_handler(int pf);
 extern void nf_reinject(struct sk_buff *skb,
--- linux-2.4.21/include/linux/netfilter_ipv4.h	Mon Feb 25 20:38:13 2002
+++ linux-2.4.21-ebt-brnf-3/include/linux/netfilter_ipv4.h	Fri Aug  8 01:09:06 2003
@@ -52,8 +52,10 @@
 enum nf_ip_hook_priorities {
 	NF_IP_PRI_FIRST = INT_MIN,
 	NF_IP_PRI_CONNTRACK = -200,
+	NF_IP_PRI_BRIDGE_SABOTAGE_FORWARD = -175,
 	NF_IP_PRI_MANGLE = -150,
 	NF_IP_PRI_NAT_DST = -100,
+	NF_IP_PRI_BRIDGE_SABOTAGE_LOCAL_OUT = -50,
 	NF_IP_PRI_FILTER = 0,
 	NF_IP_PRI_NAT_SRC = 100,
 	NF_IP_PRI_LAST = INT_MAX,
--- linux-2.4.21/include/linux/skbuff.h	Fri Jun 13 16:51:39 2003
+++ linux-2.4.21-ebt-brnf-3/include/linux/skbuff.h	Fri Aug  8 01:09:06 2003
@@ -92,6 +92,17 @@ struct nf_conntrack {
 struct nf_ct_info {
 	struct nf_conntrack *master;
 };
+
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+struct nf_bridge_info {
+	atomic_t use;
+	struct net_device *physindev;
+	struct net_device *physoutdev;
+	unsigned int mask;
+	unsigned long hh[16 / sizeof(unsigned long)];
+};
+#endif
+
 #endif
 
 struct sk_buff_head {
@@ -204,6 +215,9 @@ struct sk_buff {
 #ifdef CONFIG_NETFILTER_DEBUG
         unsigned int nf_debug;
 #endif
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+	struct nf_bridge_info	*nf_bridge;	/* Saved data about a bridged frame - see br_netfilter.c */
+#endif
 #endif /*CONFIG_NETFILTER*/
 
 #if defined(CONFIG_HIPPI)
@@ -278,7 +292,7 @@ static inline struct sk_buff *skb_get(st
  * If users==1, we are the only owner and are can avoid redundant
  * atomic change.
  */
- 
+
 /**
  *	kfree_skb - free an sk_buff
  *	@skb: buffer to free
@@ -286,7 +300,7 @@ static inline struct sk_buff *skb_get(st
  *	Drop a reference to the buffer and free it if the usage count has
  *	hit zero.
  */
- 
+
 static inline void kfree_skb(struct sk_buff *skb)
 {
 	if (atomic_read(&skb->users) == 1 || atomic_dec_and_test(&skb->users))
@@ -1165,6 +1179,20 @@ nf_conntrack_get(struct nf_ct_info *nfct
 	if (nfct)
 		atomic_inc(&nfct->master->use);
 }
+
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+static inline void nf_bridge_put(struct nf_bridge_info *nf_bridge)
+{
+	if (nf_bridge && atomic_dec_and_test(&nf_bridge->use))
+		kfree(nf_bridge);
+}
+static inline void nf_bridge_get(struct nf_bridge_info *nf_bridge)
+{
+	if (nf_bridge)
+		atomic_inc(&nf_bridge->use);
+}
+#endif
+
 #endif
 
 #endif	/* __KERNEL__ */
--- linux-2.4.21/net/core/netfilter.c	Sat Aug  3 02:39:46 2002
+++ linux-2.4.21-ebt-brnf-3/net/core/netfilter.c	Fri Aug  8 01:09:06 2003
@@ -1,4 +1,4 @@
-/* netfilter.c: look after the filters for various protocols. 
+/* netfilter.c: look after the filters for various protocols.
  * Heavily influenced by the old firewall.c by David Bonn and Alan Cox.
  *
  * Thanks to Rob `CmdrTaco' Malda for not influencing this code in any
@@ -342,10 +342,15 @@ static unsigned int nf_iterate(struct li
 			       const struct net_device *indev,
 			       const struct net_device *outdev,
 			       struct list_head **i,
-			       int (*okfn)(struct sk_buff *))
+			       int (*okfn)(struct sk_buff *),
+			       int hook_thresh)
 {
 	for (*i = (*i)->next; *i != head; *i = (*i)->next) {
 		struct nf_hook_ops *elem = (struct nf_hook_ops *)*i;
+
+		if (hook_thresh > elem->priority)
+			continue;
+
 		switch (elem->hook(hook, skb, indev, outdev, okfn)) {
 		case NF_QUEUE:
 			return NF_QUEUE;
@@ -365,7 +370,7 @@ static unsigned int nf_iterate(struct li
 			break;
 
 		default:
-			NFDEBUG("Evil return from %p(%u).\n", 
+			NFDEBUG("Evil return from %p(%u).\n",
 				elem->hook, hook);
 #endif
 		}
@@ -374,7 +379,7 @@ static unsigned int nf_iterate(struct li
 }
 
 int nf_register_queue_handler(int pf, nf_queue_outfn_t outfn, void *data)
-{      
+{
 	int ret;
 
 	br_write_lock_bh(BR_NETPROTO_LOCK);
@@ -400,12 +405,12 @@ int nf_unregister_queue_handler(int pf)
 	return 0;
 }
 
-/* 
- * Any packet that leaves via this function must come back 
+/*
+ * Any packet that leaves via this function must come back
  * through nf_reinject().
  */
-static void nf_queue(struct sk_buff *skb, 
-		     struct list_head *elem, 
+static void nf_queue(struct sk_buff *skb,
+		     struct list_head *elem,
 		     int pf, unsigned int hook,
 		     struct net_device *indev,
 		     struct net_device *outdev,
@@ -413,6 +418,10 @@ static void nf_queue(struct sk_buff *skb
 {
 	int status;
 	struct nf_info *info;
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+	struct net_device *physindev = NULL;
+	struct net_device *physoutdev = NULL;
+#endif
 
 	if (!queue_handler[pf].outfn) {
 		kfree_skb(skb);
@@ -428,18 +437,31 @@ static void nf_queue(struct sk_buff *skb
 		return;
 	}
 
-	*info = (struct nf_info) { 
+	*info = (struct nf_info) {
 		(struct nf_hook_ops *)elem, pf, hook, indev, outdev, okfn };
 
 	/* Bump dev refs so they don't vanish while packet is out */
 	if (indev) dev_hold(indev);
 	if (outdev) dev_hold(outdev);
 
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+	if (skb->nf_bridge) {
+		physindev = skb->nf_bridge->physindev;
+		if (physindev) dev_hold(physindev);
+		physoutdev = skb->nf_bridge->physoutdev;
+		if (physoutdev) dev_hold(physoutdev);
+	}
+#endif
+
 	status = queue_handler[pf].outfn(skb, info, queue_handler[pf].data);
 	if (status < 0) {
 		/* James M doesn't say fuck enough. */
 		if (indev) dev_put(indev);
 		if (outdev) dev_put(outdev);
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+		if (physindev) dev_put(physindev);
+		if (physoutdev) dev_put(physoutdev);
+#endif
 		kfree(info);
 		kfree_skb(skb);
 		return;
@@ -449,7 +471,8 @@ static void nf_queue(struct sk_buff *skb
 int nf_hook_slow(int pf, unsigned int hook, struct sk_buff *skb,
 		 struct net_device *indev,
 		 struct net_device *outdev,
-		 int (*okfn)(struct sk_buff *))
+		 int (*okfn)(struct sk_buff *),
+		 int hook_thresh)
 {
 	struct list_head *elem;
 	unsigned int verdict;
@@ -481,7 +504,7 @@ int nf_hook_slow(int pf, unsigned int ho
 
 	elem = &nf_hooks[pf][hook];
 	verdict = nf_iterate(&nf_hooks[pf][hook], &skb, hook, indev,
-			     outdev, &elem, okfn);
+			     outdev, &elem, okfn, hook_thresh);
 	if (verdict == NF_QUEUE) {
 		NFDEBUG("nf_hook: Verdict = QUEUE.\n");
 		nf_queue(skb, elem, pf, hook, indev, outdev, okfn);
@@ -510,6 +533,14 @@ void nf_reinject(struct sk_buff *skb, st
 
 	/* We don't have BR_NETPROTO_LOCK here */
 	br_read_lock_bh(BR_NETPROTO_LOCK);
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+	if (skb->nf_bridge) {
+		if (skb->nf_bridge->physindev)
+			dev_put(skb->nf_bridge->physindev);
+		if (skb->nf_bridge->physoutdev)
+			dev_put(skb->nf_bridge->physoutdev);
+	}
+#endif
 	for (i = nf_hooks[info->pf][info->hook].next; i != elem; i = i->next) {
 		if (i == &nf_hooks[info->pf][info->hook]) {
 			/* The module which sent it to userspace is gone. */
@@ -528,9 +559,9 @@ void nf_reinject(struct sk_buff *skb, st
 
 	if (verdict == NF_ACCEPT) {
 		verdict = nf_iterate(&nf_hooks[info->pf][info->hook],
-				     &skb, info->hook, 
+				     &skb, info->hook,
 				     info->indev, info->outdev, &elem,
-				     info->okfn);
+				     info->okfn, INT_MIN);
 	}
 
 	switch (verdict) {
@@ -539,20 +570,19 @@ void nf_reinject(struct sk_buff *skb, st
 		break;
 
 	case NF_QUEUE:
-		nf_queue(skb, elem, info->pf, info->hook, 
+		nf_queue(skb, elem, info->pf, info->hook,
 			 info->indev, info->outdev, info->okfn);
 		break;
-
-	case NF_DROP:
-		kfree_skb(skb);
-		break;
 	}
 	br_read_unlock_bh(BR_NETPROTO_LOCK);
 
 	/* Release those devices we held, or Alexey will kill me. */
 	if (info->indev) dev_put(info->indev);
 	if (info->outdev) dev_put(info->outdev);
-	
+
+	if (verdict == NF_DROP)
+		kfree_skb(skb);
+
 	kfree(info);
 	return;
 }
--- linux-2.4.21/net/core/skbuff.c	Fri Jun 13 16:51:39 2003
+++ linux-2.4.21-ebt-brnf-3/net/core/skbuff.c	Fri Aug  8 01:09:06 2003
@@ -245,6 +245,9 @@ static inline void skb_headerinit(void *
 #ifdef CONFIG_NETFILTER_DEBUG
 	skb->nf_debug = 0;
 #endif
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+	skb->nf_bridge	  = NULL;
+#endif
 #endif
 #ifdef CONFIG_NET_SCHED
 	skb->tc_index = 0;
@@ -325,6 +328,9 @@ void __kfree_skb(struct sk_buff *skb)
 	}
 #ifdef CONFIG_NETFILTER
 	nf_conntrack_put(skb->nfct);
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+	nf_bridge_put(skb->nf_bridge);
+#endif
 #endif
 	skb_headerinit(skb, NULL, 0);  /* clean state */
 	kfree_skbmem(skb);
@@ -391,6 +397,9 @@ struct sk_buff *skb_clone(struct sk_buff
 #ifdef CONFIG_NETFILTER_DEBUG
 	C(nf_debug);
 #endif
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+	C(nf_bridge);
+#endif
 #endif /*CONFIG_NETFILTER*/
 #if defined(CONFIG_HIPPI)
 	C(private);
@@ -403,6 +412,9 @@ struct sk_buff *skb_clone(struct sk_buff
 	skb->cloned = 1;
 #ifdef CONFIG_NETFILTER
 	nf_conntrack_get(skb->nfct);
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+	nf_bridge_get(skb->nf_bridge);
+#endif
 #endif
 	return n;
 }
@@ -436,6 +448,10 @@ static void copy_skb_header(struct sk_bu
 	nf_conntrack_get(new->nfct);
 #ifdef CONFIG_NETFILTER_DEBUG
 	new->nf_debug=old->nf_debug;
+#endif
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+	new->nf_bridge=old->nf_bridge;
+	nf_bridge_get(new->nf_bridge);
 #endif
 #endif
 #ifdef CONFIG_NET_SCHED
--- linux-2.4.21/net/ipv4/netfilter/ip_tables.c	Fri Jun 13 16:51:39 2003
+++ linux-2.4.21-ebt-brnf-3/net/ipv4/netfilter/ip_tables.c	Fri Aug  8 01:09:06 2003
@@ -121,12 +121,19 @@ static LIST_HEAD(ipt_tables);
 static inline int
 ip_packet_match(const struct iphdr *ip,
 		const char *indev,
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+		const char *physindev,
+#endif
 		const char *outdev,
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+		const char *physoutdev,
+#endif
 		const struct ipt_ip *ipinfo,
 		int isfrag)
 {
 	size_t i;
 	unsigned long ret;
+	unsigned long ret2 = 1;
 
 #define FWINV(bool,invflg) ((bool) ^ !!(ipinfo->invflags & invflg))
 
@@ -156,7 +163,15 @@ ip_packet_match(const struct iphdr *ip,
 			& ((const unsigned long *)ipinfo->iniface_mask)[i];
 	}
 
-	if (FWINV(ret != 0, IPT_INV_VIA_IN)) {
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+	for (i = 0, ret2 = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) {
+		ret2 |= (((const unsigned long *)physindev)[i]
+			^ ((const unsigned long *)ipinfo->iniface)[i])
+			& ((const unsigned long *)ipinfo->iniface_mask)[i];
+	}
+#endif
+
+	if (FWINV(ret != 0 && ret2 != 0, IPT_INV_VIA_IN)) {
 		dprintf("VIA in mismatch (%s vs %s).%s\n",
 			indev, ipinfo->iniface,
 			ipinfo->invflags&IPT_INV_VIA_IN ?" (INV)":"");
@@ -169,7 +184,15 @@ ip_packet_match(const struct iphdr *ip,
 			& ((const unsigned long *)ipinfo->outiface_mask)[i];
 	}
 
-	if (FWINV(ret != 0, IPT_INV_VIA_OUT)) {
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+	for (i = 0, ret2 = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) {
+		ret2 |= (((const unsigned long *)physoutdev)[i]
+			^ ((const unsigned long *)ipinfo->outiface)[i])
+			& ((const unsigned long *)ipinfo->outiface_mask)[i];
+	}
+#endif
+
+	if (FWINV(ret != 0 && ret2 != 0, IPT_INV_VIA_OUT)) {
 		dprintf("VIA out mismatch (%s vs %s).%s\n",
 			outdev, ipinfo->outiface,
 			ipinfo->invflags&IPT_INV_VIA_OUT ?" (INV)":"");
@@ -268,6 +291,9 @@ ipt_do_table(struct sk_buff **pskb,
 	/* Initializing verdict to NF_DROP keeps gcc happy. */
 	unsigned int verdict = NF_DROP;
 	const char *indev, *outdev;
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+	const char *physindev, *physoutdev;
+#endif
 	void *table_base;
 	struct ipt_entry *e, *back;
 
@@ -277,6 +303,13 @@ ipt_do_table(struct sk_buff **pskb,
 	datalen = (*pskb)->len - ip->ihl * 4;
 	indev = in ? in->name : nulldevname;
 	outdev = out ? out->name : nulldevname;
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+	physindev = ((*pskb)->nf_bridge && (*pskb)->nf_bridge->physindev) ?
+		(*pskb)->nf_bridge->physindev->name : nulldevname;
+	physoutdev = ((*pskb)->nf_bridge && (*pskb)->nf_bridge->physoutdev) ?
+		(*pskb)->nf_bridge->physoutdev->name : nulldevname;
+#endif
+
 	/* We handle fragments by dealing with the first fragment as
 	 * if it was a normal packet.  All other fragments are treated
 	 * normally, except that they will NEVER match rules that ask
@@ -312,7 +345,15 @@ ipt_do_table(struct sk_buff **pskb,
 		IP_NF_ASSERT(e);
 		IP_NF_ASSERT(back);
 		(*pskb)->nfcache |= e->nfcache;
-		if (ip_packet_match(ip, indev, outdev, &e->ip, offset)) {
+		if (ip_packet_match(ip, indev,
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+		    physindev,
+#endif
+		    outdev,
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+		    physoutdev,
+#endif
+		    &e->ip, offset)) {
 			struct ipt_entry_target *t;
 
 			if (IPT_MATCH_ITERATE(e, do_match,
--- linux-2.4.21/net/ipv4/ip_output.c	Fri Nov 29 00:53:15 2002
+++ linux-2.4.21-ebt-brnf-3/net/ipv4/ip_output.c	Fri Aug  8 01:09:06 2003
@@ -879,6 +879,10 @@ int ip_fragment(struct sk_buff *skb, int
 		/* Connection association is same as pre-frag packet */
 		skb2->nfct = skb->nfct;
 		nf_conntrack_get(skb2->nfct);
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+		skb2->nf_bridge = skb->nf_bridge;
+		nf_bridge_get(skb2->nf_bridge);
+#endif
 #ifdef CONFIG_NETFILTER_DEBUG
 		skb2->nf_debug = skb->nf_debug;
 #endif
--- linux-2.4.21/net/ipv4/netfilter/ipt_LOG.c	Mon Feb 25 20:38:14 2002
+++ linux-2.4.21-ebt-brnf-3/net/ipv4/netfilter/ipt_LOG.c	Fri Aug  8 01:09:06 2003
@@ -289,6 +289,18 @@ ipt_log_target(struct sk_buff **pskb,
 	       loginfo->prefix,
 	       in ? in->name : "",
 	       out ? out->name : "");
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+	if ((*pskb)->nf_bridge) {
+		struct net_device *physindev = (*pskb)->nf_bridge->physindev;
+		struct net_device *physoutdev = (*pskb)->nf_bridge->physoutdev;
+
+		if (physindev && in != physindev)
+			printk("PHYSIN=%s ", physindev->name);
+		if (physoutdev && out != physoutdev)
+			printk("PHYSOUT=%s ", physoutdev->name);
+	}
+#endif
+
 	if (in && !out) {
 		/* MAC logging for input chain only. */
 		printk("MAC=");
--- linux-2.4.21/net/ipv4/netfilter/Makefile	Fri Jun 13 16:51:39 2003
+++ linux-2.4.21-ebt-brnf-3/net/ipv4/netfilter/Makefile	Fri Aug  8 01:09:06 2003
@@ -84,6 +84,8 @@ obj-$(CONFIG_IP_NF_MATCH_CONNTRACK) += i
 obj-$(CONFIG_IP_NF_MATCH_UNCLEAN) += ipt_unclean.o
 obj-$(CONFIG_IP_NF_MATCH_TCPMSS) += ipt_tcpmss.o
 
+obj-$(CONFIG_IP_NF_MATCH_PHYSDEV) += ipt_physdev.o
+
 # targets
 obj-$(CONFIG_IP_NF_TARGET_REJECT) += ipt_REJECT.o
 obj-$(CONFIG_IP_NF_TARGET_MIRROR) += ipt_MIRROR.o
--- linux-2.4.21/net/ipv4/netfilter/Config.in	Fri Jun 13 16:51:39 2003
+++ linux-2.4.21-ebt-brnf-3/net/ipv4/netfilter/Config.in	Fri Aug  8 01:09:06 2003
@@ -43,6 +43,9 @@ if [ "$CONFIG_IP_NF_IPTABLES" != "n" ]; 
     dep_tristate '  Unclean match support (EXPERIMENTAL)' CONFIG_IP_NF_MATCH_UNCLEAN $CONFIG_IP_NF_IPTABLES
     dep_tristate '  Owner match support (EXPERIMENTAL)' CONFIG_IP_NF_MATCH_OWNER $CONFIG_IP_NF_IPTABLES
   fi
+  if [ "$CONFIG_BRIDGE" != "n" ]; then
+    dep_tristate '  Physdev match support' CONFIG_IP_NF_MATCH_PHYSDEV
+  fi
 # The targets
   dep_tristate '  Packet filtering' CONFIG_IP_NF_FILTER $CONFIG_IP_NF_IPTABLES 
   if [ "$CONFIG_IP_NF_FILTER" != "n" ]; then
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/net/bridge/br_netfilter.c	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,636 @@
+/*
+ *	Handle firewalling
+ *	Linux ethernet bridge
+ *
+ *	Authors:
+ *	Lennert Buytenhek               <buytenh@gnu.org>
+ *	Bart De Schuymer		<bdschuym@pandora.be>
+ *
+ *	This program is free software; you can redistribute it and/or
+ *	modify it under the terms of the GNU General Public License
+ *	as published by the Free Software Foundation; either version
+ *	2 of the License, or (at your option) any later version.
+ *
+ *	Lennert dedicates this file to Kerstin Wurdinger.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/ip.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <linux/if_ether.h>
+#include <linux/netfilter_bridge.h>
+#include <linux/netfilter_ipv4.h>
+#include <linux/in_route.h>
+#include <net/ip.h>
+#include <asm/uaccess.h>
+#include <asm/checksum.h>
+#include "br_private.h"
+
+
+#define skb_origaddr(skb)	 (((struct bridge_skb_cb *) \
+				 (skb->cb))->daddr.ipv4)
+#define store_orig_dstaddr(skb)	 (skb_origaddr(skb) = (skb)->nh.iph->daddr)
+#define dnat_took_place(skb)	 (skb_origaddr(skb) != (skb)->nh.iph->daddr)
+#define clear_cb(skb)		 (memset(&skb_origaddr(skb), 0, \
+				 sizeof(struct bridge_skb_cb)))
+
+#define has_bridge_parent(device)	((device)->br_port != NULL)
+#define bridge_parent(device)		(&((device)->br_port->br->dev))
+
+/* We need these fake structures to make netfilter happy --
+ * lots of places assume that skb->dst != NULL, which isn't
+ * all that unreasonable.
+ *
+ * Currently, we fill in the PMTU entry because netfilter
+ * refragmentation needs it, and the rt_flags entry because
+ * ipt_REJECT needs it.  Future netfilter modules might
+ * require us to fill additional fields.
+ */
+static struct net_device __fake_net_device = {
+	.hard_header_len	= ETH_HLEN
+};
+
+static struct rtable __fake_rtable = {
+	u: {
+		dst: {
+			__refcnt:		ATOMIC_INIT(1),
+			dev:			&__fake_net_device,
+			pmtu:			1500
+		}
+	},
+
+	rt_flags:	0
+};
+
+
+/* PF_BRIDGE/PRE_ROUTING *********************************************/
+static void __br_dnat_complain(void)
+{
+	static unsigned long last_complaint = 0;
+
+	if (jiffies - last_complaint >= 5 * HZ) {
+		printk(KERN_WARNING "Performing cross-bridge DNAT requires IP "
+			"forwarding to be enabled\n");
+		last_complaint = jiffies;
+	}
+}
+
+
+/* This requires some explaining. If DNAT has taken place,
+ * we will need to fix up the destination Ethernet address,
+ * and this is a tricky process.
+ *
+ * There are two cases to consider:
+ * 1. The packet was DNAT'ed to a device in the same bridge
+ *    port group as it was received on. We can still bridge
+ *    the packet.
+ * 2. The packet was DNAT'ed to a different device, either
+ *    a non-bridged device or another bridge port group.
+ *    The packet will need to be routed.
+ *
+ * The correct way of distinguishing between these two cases is to
+ * call ip_route_input() and to look at skb->dst->dev, which is
+ * changed to the destination device if ip_route_input() succeeds.
+ *
+ * Let us first consider the case that ip_route_input() succeeds:
+ *
+ * If skb->dst->dev equals the logical bridge device the packet
+ * came in on, we can consider this bridging. We then call
+ * skb->dst->output() which will make the packet enter br_nf_local_out()
+ * not much later. In that function it is assured that the iptables
+ * FORWARD chain is traversed for the packet.
+ *
+ * Otherwise, the packet is considered to be routed and we just
+ * change the destination MAC address so that the packet will
+ * later be passed up to the IP stack to be routed.
+ *
+ * Let us now consider the case that ip_route_input() fails:
+ *
+ * After a "echo '0' > /proc/sys/net/ipv4/ip_forward" ip_route_input()
+ * will fail, while __ip_route_output_key() will return success. The source
+ * address for __ip_route_output_key() is set to zero, so __ip_route_output_key
+ * thinks we're handling a locally generated packet and won't care
+ * if IP forwarding is allowed. We send a warning message to the users's
+ * log telling her to put IP forwarding on.
+ *
+ * ip_route_input() will also fail if there is no route available.
+ * In that case we just drop the packet.
+ *
+ * --Lennert, 20020411
+ * --Bart, 20020416 (updated)
+ * --Bart, 20021007 (updated)
+ */
+
+static int br_nf_pre_routing_finish_bridge(struct sk_buff *skb)
+{
+#ifdef CONFIG_NETFILTER_DEBUG
+	skb->nf_debug |= (1 << NF_BR_PRE_ROUTING) | (1 << NF_BR_FORWARD);
+#endif
+
+	if (skb->pkt_type == PACKET_OTHERHOST) {
+		skb->pkt_type = PACKET_HOST;
+		skb->nf_bridge->mask |= BRNF_PKT_TYPE;
+	}
+
+	skb->dev = bridge_parent(skb->dev);
+	skb->dst->output(skb);
+	return 0;
+}
+
+static int br_nf_pre_routing_finish(struct sk_buff *skb)
+{
+	struct net_device *dev = skb->dev;
+	struct iphdr *iph = skb->nh.iph;
+	struct nf_bridge_info *nf_bridge = skb->nf_bridge;
+
+#ifdef CONFIG_NETFILTER_DEBUG
+	skb->nf_debug ^= (1 << NF_BR_PRE_ROUTING);
+#endif
+
+	if (nf_bridge->mask & BRNF_PKT_TYPE) {
+		skb->pkt_type = PACKET_OTHERHOST;
+		nf_bridge->mask ^= BRNF_PKT_TYPE;
+	}
+
+	if (dnat_took_place(skb)) {
+		if (ip_route_input(skb, iph->daddr, iph->saddr, iph->tos,
+		    dev)) {
+			struct rtable *rt;
+
+			if (!ip_route_output(&rt, iph->daddr, 0, iph->tos, 0)) {
+				/* Bridged-and-DNAT'ed traffic doesn't
+				 * require ip_forwarding.
+				 */
+				if (((struct dst_entry *)rt)->dev == dev) {
+					skb->dst = (struct dst_entry *)rt;
+					goto bridged_dnat;
+				}
+				__br_dnat_complain();
+				dst_release((struct dst_entry *)rt);
+			}
+			kfree_skb(skb);
+			return 0;
+		} else {
+			if (skb->dst->dev == dev) {
+bridged_dnat:
+				/* Tell br_nf_local_out this is a
+				 * bridged frame
+				 */
+				nf_bridge->mask |= BRNF_BRIDGED_DNAT;
+				skb->dev = nf_bridge->physindev;
+				clear_cb(skb);
+				NF_HOOK_THRESH(PF_BRIDGE, NF_BR_PRE_ROUTING,
+					       skb, skb->dev, NULL,
+					       br_nf_pre_routing_finish_bridge,
+					       1);
+				return 0;
+			}
+			memcpy(skb->mac.ethernet->h_dest, dev->dev_addr,
+			       ETH_ALEN);
+		}
+	} else {
+		skb->dst = (struct dst_entry *)&__fake_rtable;
+		dst_hold(skb->dst);
+	}
+
+	clear_cb(skb);
+	skb->dev = nf_bridge->physindev;
+	NF_HOOK_THRESH(PF_BRIDGE, NF_BR_PRE_ROUTING, skb, skb->dev, NULL,
+		       br_handle_frame_finish, 1);
+
+	return 0;
+}
+
+/* Replicate the checks that IPv4 does on packet reception.
+ * Set skb->dev to the bridge device (i.e. parent of the
+ * receiving device) to make netfilter happy, the REDIRECT
+ * target in particular.  Save the original destination IP
+ * address to be able to detect DNAT afterwards.
+ */
+static unsigned int br_nf_pre_routing(unsigned int hook, struct sk_buff **pskb,
+   const struct net_device *in, const struct net_device *out,
+   int (*okfn)(struct sk_buff *))
+{
+	struct iphdr *iph;
+	__u32 len;
+	struct sk_buff *skb;
+	struct nf_bridge_info *nf_bridge;
+
+	if ((*pskb)->protocol != __constant_htons(ETH_P_IP))
+		return NF_ACCEPT;
+
+	if ((skb = skb_share_check(*pskb, GFP_ATOMIC)) == NULL)
+		goto out;
+
+	if (!pskb_may_pull(skb, sizeof(struct iphdr)))
+		goto inhdr_error;
+
+	iph = skb->nh.iph;
+	if (iph->ihl < 5 || iph->version != 4)
+		goto inhdr_error;
+
+	if (!pskb_may_pull(skb, 4*iph->ihl))
+		goto inhdr_error;
+
+	iph = skb->nh.iph;
+	if (ip_fast_csum((__u8 *)iph, iph->ihl) != 0)
+		goto inhdr_error;
+
+	len = ntohs(iph->tot_len);
+	if (skb->len < len || len < 4*iph->ihl)
+		goto inhdr_error;
+
+	if (skb->len > len) {
+		__pskb_trim(skb, len);
+		if (skb->ip_summed == CHECKSUM_HW)
+			skb->ip_summed = CHECKSUM_NONE;
+	}
+
+#ifdef CONFIG_NETFILTER_DEBUG
+	skb->nf_debug ^= (1 << NF_IP_PRE_ROUTING);
+#endif
+ 	if ((nf_bridge = nf_bridge_alloc(skb)) == NULL)
+		return NF_DROP;
+
+	if (skb->pkt_type == PACKET_OTHERHOST) {
+		skb->pkt_type = PACKET_HOST;
+		nf_bridge->mask |= BRNF_PKT_TYPE;
+	}
+
+	nf_bridge->physindev = skb->dev;
+	skb->dev = bridge_parent(skb->dev);
+	store_orig_dstaddr(skb);
+
+	NF_HOOK(PF_INET, NF_IP_PRE_ROUTING, skb, skb->dev, NULL,
+		br_nf_pre_routing_finish);
+
+	return NF_STOLEN;
+
+inhdr_error:
+//	IP_INC_STATS_BH(IpInHdrErrors);
+out:
+	return NF_DROP;
+}
+
+
+/* PF_BRIDGE/LOCAL_IN ************************************************/
+/* The packet is locally destined, which requires a real
+ * dst_entry, so detach the fake one.  On the way up, the
+ * packet would pass through PRE_ROUTING again (which already
+ * took place when the packet entered the bridge), but we
+ * register an IPv4 PRE_ROUTING 'sabotage' hook that will
+ * prevent this from happening.
+ */
+static unsigned int br_nf_local_in(unsigned int hook, struct sk_buff **pskb,
+   const struct net_device *in, const struct net_device *out,
+   int (*okfn)(struct sk_buff *))
+{
+	struct sk_buff *skb = *pskb;
+
+	if (skb->protocol != __constant_htons(ETH_P_IP))
+		return NF_ACCEPT;
+
+	if (skb->dst == (struct dst_entry *)&__fake_rtable) {
+		dst_release(skb->dst);
+		skb->dst = NULL;
+	}
+
+	return NF_ACCEPT;
+}
+
+
+/* PF_BRIDGE/FORWARD *************************************************/
+static int br_nf_forward_finish(struct sk_buff *skb)
+{
+	struct nf_bridge_info *nf_bridge = skb->nf_bridge;
+
+#ifdef CONFIG_NETFILTER_DEBUG
+	skb->nf_debug ^= (1 << NF_BR_FORWARD);
+#endif
+
+	if (nf_bridge->mask & BRNF_PKT_TYPE) {
+		skb->pkt_type = PACKET_OTHERHOST;
+		nf_bridge->mask ^= BRNF_PKT_TYPE;
+	}
+
+	NF_HOOK_THRESH(PF_BRIDGE, NF_BR_FORWARD, skb, nf_bridge->physindev,
+			skb->dev, br_forward_finish, 1);
+
+	return 0;
+}
+
+/* This is the 'purely bridged' case.  We pass the packet to
+ * netfilter with indev and outdev set to the bridge device,
+ * but we are still able to filter on the 'real' indev/outdev
+ * because of the ipt_physdev.c module.
+ */
+static unsigned int br_nf_forward(unsigned int hook, struct sk_buff **pskb,
+   const struct net_device *in, const struct net_device *out,
+   int (*okfn)(struct sk_buff *))
+{
+	struct sk_buff *skb = *pskb;
+	struct nf_bridge_info *nf_bridge;
+
+	if (skb->protocol != __constant_htons(ETH_P_IP))
+		return NF_ACCEPT;
+
+#ifdef CONFIG_NETFILTER_DEBUG
+	skb->nf_debug ^= (1 << NF_BR_FORWARD);
+#endif
+
+	nf_bridge = skb->nf_bridge;
+	if (skb->pkt_type == PACKET_OTHERHOST) {
+		skb->pkt_type = PACKET_HOST;
+		nf_bridge->mask |= BRNF_PKT_TYPE;
+	}
+
+	nf_bridge->mask |= BRNF_BRIDGED; /* The physdev module checks on this */
+	nf_bridge->physoutdev = skb->dev;
+
+	NF_HOOK(PF_INET, NF_IP_FORWARD, skb, bridge_parent(nf_bridge->physindev),
+			bridge_parent(skb->dev), br_nf_forward_finish);
+
+	return NF_STOLEN;
+}
+
+
+/* PF_BRIDGE/LOCAL_OUT ***********************************************/
+static int br_nf_local_out_finish(struct sk_buff *skb)
+{
+#ifdef CONFIG_NETFILTER_DEBUG
+	skb->nf_debug &= ~(1 << NF_BR_LOCAL_OUT);
+#endif
+
+	NF_HOOK_THRESH(PF_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
+			br_forward_finish, NF_BR_PRI_FIRST + 1);
+
+	return 0;
+}
+
+
+/* This function sees both locally originated IP packets and forwarded
+ * IP packets (in both cases the destination device is a bridge
+ * device). It also sees bridged-and-DNAT'ed packets.
+ * To be able to filter on the physical bridge devices (with the ipt_physdev.c
+ * module), we steal packets destined to a bridge device away from the
+ * PF_INET/FORWARD and PF_INET/OUTPUT hook functions, and give them back later,
+ * when we have determined the real output device. This is done in here.
+ *
+ * If (nf_bridge->mask & BRNF_BRIDGED_DNAT) then the packet is bridged
+ * and we fake the PF_BRIDGE/FORWARD hook. The function br_nf_forward()
+ * will then fake the PF_INET/FORWARD hook. br_nf_local_out() has priority
+ * NF_BR_PRI_FIRST, so no relevant PF_BRIDGE/INPUT functions have been nor
+ * will be executed.
+ * Otherwise, if nf_bridge->physindev is NULL, the bridge-nf code never touched
+ * this packet before, and so the packet was locally originated. We fake
+ * the PF_INET/LOCAL_OUT hook.
+ * Finally, if nf_bridge->physindev isn't NULL, then the packet was IP routed,
+ * so we fake the PF_INET/FORWARD hook. ipv4_sabotage_out() makes sure
+ * even routed packets that didn't arrive on a bridge interface have their
+ * nf_bridge->physindev set.
+ */
+
+static unsigned int br_nf_local_out(unsigned int hook, struct sk_buff **pskb,
+   const struct net_device *in, const struct net_device *out,
+   int (*_okfn)(struct sk_buff *))
+{
+	int (*okfn)(struct sk_buff *skb);
+	struct net_device *realindev;
+	struct sk_buff *skb = *pskb;
+	struct nf_bridge_info *nf_bridge;
+
+	if (skb->protocol != __constant_htons(ETH_P_IP))
+		return NF_ACCEPT;
+
+	/* Sometimes we get packets with NULL ->dst here (for example,
+	 * running a dhcp client daemon triggers this).
+	 */
+	if (skb->dst == NULL)
+		return NF_ACCEPT;
+
+	nf_bridge = skb->nf_bridge;
+	nf_bridge->physoutdev = skb->dev;
+
+	realindev = nf_bridge->physindev;
+
+	/* Bridged, take PF_BRIDGE/FORWARD.
+	 * (see big note in front of br_nf_pre_routing_finish)
+	 */
+	if (nf_bridge->mask & BRNF_BRIDGED_DNAT) {
+		okfn = br_forward_finish;
+
+		if (nf_bridge->mask & BRNF_PKT_TYPE) {
+			skb->pkt_type = PACKET_OTHERHOST;
+			nf_bridge->mask ^= BRNF_PKT_TYPE;
+		}
+
+		NF_HOOK(PF_BRIDGE, NF_BR_FORWARD, skb, realindev,
+			skb->dev, okfn);
+	} else {
+		okfn = br_nf_local_out_finish;
+		/* IP forwarded traffic has a physindev, locally
+		 * generated traffic hasn't.
+		 */
+		if (realindev != NULL) {
+			if (((nf_bridge->mask & BRNF_DONT_TAKE_PARENT) == 0) &&
+			    has_bridge_parent(realindev))
+				realindev = bridge_parent(realindev);
+
+			NF_HOOK_THRESH(PF_INET, NF_IP_FORWARD, skb, realindev,
+				       bridge_parent(skb->dev), okfn,
+				       NF_IP_PRI_BRIDGE_SABOTAGE_FORWARD + 1);
+		} else {
+#ifdef CONFIG_NETFILTER_DEBUG
+			skb->nf_debug ^= (1 << NF_IP_LOCAL_OUT);
+#endif
+
+			NF_HOOK_THRESH(PF_INET, NF_IP_LOCAL_OUT, skb, realindev,
+				       bridge_parent(skb->dev), okfn,
+				       NF_IP_PRI_BRIDGE_SABOTAGE_LOCAL_OUT + 1);
+		}
+	}
+
+	return NF_STOLEN;
+}
+
+
+/* PF_BRIDGE/POST_ROUTING ********************************************/
+static unsigned int br_nf_post_routing(unsigned int hook, struct sk_buff **pskb,
+   const struct net_device *in, const struct net_device *out,
+   int (*okfn)(struct sk_buff *))
+{
+	struct sk_buff *skb = *pskb;
+	struct nf_bridge_info *nf_bridge = (*pskb)->nf_bridge;
+
+	/* Be very paranoid. Must be a device driver bug. */
+	if (skb->mac.raw < skb->head || skb->mac.raw + ETH_HLEN > skb->data) {
+		printk(KERN_CRIT "br_netfilter: Argh!! br_nf_post_routing: "
+				 "bad mac.raw pointer.");
+		if (skb->dev != NULL) {
+			printk("[%s]", skb->dev->name);
+			if (has_bridge_parent(skb->dev))
+				printk("[%s]", bridge_parent(skb->dev)->name);
+		}
+		printk("\n");
+		return NF_ACCEPT;
+	}
+
+	if (skb->protocol != __constant_htons(ETH_P_IP))
+		return NF_ACCEPT;
+
+	/* Sometimes we get packets with NULL ->dst here (for example,
+	 * running a dhcp client daemon triggers this).
+	 */
+	if (skb->dst == NULL)
+		return NF_ACCEPT;
+
+#ifdef CONFIG_NETFILTER_DEBUG
+	skb->nf_debug ^= (1 << NF_IP_POST_ROUTING);
+#endif
+
+	/* We assume any code from br_dev_queue_push_xmit onwards doesn't care
+	 * about the value of skb->pkt_type.
+	 */
+	if (skb->pkt_type == PACKET_OTHERHOST) {
+		skb->pkt_type = PACKET_HOST;
+		nf_bridge->mask |= BRNF_PKT_TYPE;
+	}
+
+	memcpy(nf_bridge->hh, skb->data - 16, 16);
+
+	NF_HOOK(PF_INET, NF_IP_POST_ROUTING, skb, NULL,
+		bridge_parent(skb->dev), br_dev_queue_push_xmit);
+
+	return NF_STOLEN;
+}
+
+
+/* IPv4/SABOTAGE *****************************************************/
+
+/* Don't hand locally destined packets to PF_INET/PRE_ROUTING
+ * for the second time.
+ */
+static unsigned int ipv4_sabotage_in(unsigned int hook, struct sk_buff **pskb,
+   const struct net_device *in, const struct net_device *out,
+   int (*okfn)(struct sk_buff *))
+{
+	if (in->hard_start_xmit == br_dev_xmit &&
+	    okfn != br_nf_pre_routing_finish) {
+		okfn(*pskb);
+		return NF_STOLEN;
+	}
+
+	return NF_ACCEPT;
+}
+
+/* Postpone execution of PF_INET/FORWARD, PF_INET/LOCAL_OUT
+ * and PF_INET/POST_ROUTING until we have done the forwarding
+ * decision in the bridge code and have determined skb->physoutdev.
+ */
+static unsigned int ipv4_sabotage_out(unsigned int hook, struct sk_buff **pskb,
+   const struct net_device *in, const struct net_device *out,
+   int (*okfn)(struct sk_buff *))
+{
+	if (out->hard_start_xmit == br_dev_xmit &&
+	    okfn != br_nf_forward_finish &&
+	    okfn != br_nf_local_out_finish &&
+	    okfn != br_dev_queue_push_xmit) {
+		struct sk_buff *skb = *pskb;
+		struct nf_bridge_info *nf_bridge;
+
+		if (!skb->nf_bridge && !nf_bridge_alloc(skb))
+			return NF_DROP;
+
+		nf_bridge = skb->nf_bridge;
+
+		/* This frame will arrive on PF_BRIDGE/LOCAL_OUT and we
+		 * will need the indev then. For a brouter, the real indev
+		 * can be a bridge port, so we make sure br_nf_local_out()
+		 * doesn't use the bridge parent of the indev by using
+		 * the BRNF_DONT_TAKE_PARENT mask.
+		 */
+		if (hook == NF_IP_FORWARD && nf_bridge->physindev == NULL) {
+			nf_bridge->mask &= BRNF_DONT_TAKE_PARENT;
+			nf_bridge->physindev = (struct net_device *)in;
+		}
+		okfn(skb);
+		return NF_STOLEN;
+	}
+
+	return NF_ACCEPT;
+}
+
+/* For br_nf_local_out we need (prio = NF_BR_PRI_FIRST), to insure that innocent
+ * PF_BRIDGE/NF_BR_LOCAL_OUT functions don't get bridged traffic as input.
+ * For br_nf_post_routing, we need (prio = NF_BR_PRI_LAST), because
+ * ip_refrag() can return NF_STOLEN.
+ */
+static struct nf_hook_ops br_nf_ops[] = {
+	{ .hook = br_nf_pre_routing,
+	  .pf = PF_BRIDGE,
+	  .hooknum = NF_BR_PRE_ROUTING,
+	  .priority = NF_BR_PRI_BRNF, },
+	{ .hook = br_nf_local_in,
+	  .pf = PF_BRIDGE,
+	  .hooknum = NF_BR_LOCAL_IN,
+	  .priority = NF_BR_PRI_BRNF, },
+	{ .hook = br_nf_forward,
+	  .pf = PF_BRIDGE,
+	  .hooknum = NF_BR_FORWARD,
+	  .priority = NF_BR_PRI_BRNF, },
+	{ .hook = br_nf_local_out,
+	  .pf = PF_BRIDGE,
+	  .hooknum = NF_BR_LOCAL_OUT,
+	  .priority = NF_BR_PRI_FIRST, },
+	{ .hook = br_nf_post_routing,
+	  .pf = PF_BRIDGE,
+	  .hooknum = NF_BR_POST_ROUTING,
+	  .priority = NF_BR_PRI_LAST, },
+	{ .hook = ipv4_sabotage_in,
+	  .pf = PF_INET,
+	  .hooknum = NF_IP_PRE_ROUTING,
+	  .priority = NF_IP_PRI_FIRST, },
+	{ .hook = ipv4_sabotage_out,
+	  .pf = PF_INET,
+	  .hooknum = NF_IP_FORWARD,
+	  .priority = NF_IP_PRI_BRIDGE_SABOTAGE_FORWARD, },
+	{ .hook = ipv4_sabotage_out,
+	  .pf = PF_INET,
+	  .hooknum = NF_IP_LOCAL_OUT,
+	  .priority = NF_IP_PRI_BRIDGE_SABOTAGE_LOCAL_OUT, },
+	{ .hook = ipv4_sabotage_out,
+	  .pf = PF_INET,
+	  .hooknum = NF_IP_POST_ROUTING,
+	  .priority = NF_IP_PRI_FIRST, },
+};
+
+int br_netfilter_init(void)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(br_nf_ops); i++) {
+		int ret;
+
+		if ((ret = nf_register_hook(&br_nf_ops[i])) >= 0)
+			continue;
+
+		while (i--)
+			nf_unregister_hook(&br_nf_ops[i]);
+
+		return ret;
+	}
+
+	printk(KERN_NOTICE "Bridge firewalling registered\n");
+
+	return 0;
+}
+
+void br_netfilter_fini(void)
+{
+	int i;
+
+	for (i = ARRAY_SIZE(br_nf_ops) - 1; i >= 0; i--)
+		nf_unregister_hook(&br_nf_ops[i]);
+}
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/net/ipv4/netfilter/ipt_physdev.c	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,127 @@
+/* Kernel module to match the bridge port in and
+ * out device for IP packets coming into contact with a bridge. */
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/netfilter_ipv4/ipt_physdev.h>
+#include <linux/netfilter_ipv4/ip_tables.h>
+#include <linux/netfilter_bridge.h>
+#include <linux/netdevice.h>
+#define MATCH   1
+#define NOMATCH 0
+
+static int
+match(const struct sk_buff *skb,
+      const struct net_device *in,
+      const struct net_device *out,
+      const void *matchinfo,
+      int offset,
+      const void *hdr,
+      u_int16_t datalen,
+      int *hotdrop)
+{
+	int i;
+	static const char nulldevname[IFNAMSIZ] = { 0 };
+	const struct ipt_physdev_info *info = matchinfo;
+	unsigned long ret;
+	const char *indev, *outdev;
+	struct nf_bridge_info *nf_bridge;
+
+	/* Not a bridged IP packet or no info available yet:
+	 * LOCAL_OUT/mangle and LOCAL_OUT/nat don't know if
+	 * the destination device will be a bridge. */
+	if (!(nf_bridge = skb->nf_bridge)) {
+		/* Return MATCH if the invert flags of the used options are on */
+		if ((info->bitmask & IPT_PHYSDEV_OP_BRIDGED) &&
+		    !(info->invert & IPT_PHYSDEV_OP_BRIDGED))
+			return NOMATCH;
+		if ((info->bitmask & IPT_PHYSDEV_OP_ISIN) &&
+		    !(info->invert & IPT_PHYSDEV_OP_ISIN))
+			return NOMATCH;
+		if ((info->bitmask & IPT_PHYSDEV_OP_ISOUT) &&
+		    !(info->invert & IPT_PHYSDEV_OP_ISOUT))
+			return NOMATCH;
+		if ((info->bitmask & IPT_PHYSDEV_OP_IN) &&
+		    !(info->invert & IPT_PHYSDEV_OP_IN))
+			return NOMATCH;
+		if ((info->bitmask & IPT_PHYSDEV_OP_OUT) &&
+		    !(info->invert & IPT_PHYSDEV_OP_OUT))
+			return NOMATCH;
+		return MATCH;
+	}
+
+	/* This only makes sense in the FORWARD and POSTROUTING chains */
+	if ((info->bitmask & IPT_PHYSDEV_OP_BRIDGED) &&
+	    (!!(nf_bridge->mask & BRNF_BRIDGED) ^
+	    !(info->invert & IPT_PHYSDEV_OP_BRIDGED)))
+		return NOMATCH;
+
+	if ((info->bitmask & IPT_PHYSDEV_OP_ISIN &&
+	    (!nf_bridge->physindev ^ !!(info->invert & IPT_PHYSDEV_OP_ISIN))) ||
+	    (info->bitmask & IPT_PHYSDEV_OP_ISOUT &&
+	    (!nf_bridge->physoutdev ^ !!(info->invert & IPT_PHYSDEV_OP_ISOUT))))
+		return NOMATCH;
+
+	if (!(info->bitmask & IPT_PHYSDEV_OP_IN))
+		goto match_outdev;
+	indev = nf_bridge->physindev ? nf_bridge->physindev->name : nulldevname;
+	for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) {
+		ret |= (((const unsigned long *)indev)[i]
+			^ ((const unsigned long *)info->physindev)[i])
+			& ((const unsigned long *)info->in_mask)[i];
+	}
+
+	if ((ret == 0) ^ !(info->invert & IPT_PHYSDEV_OP_IN))
+		return NOMATCH;
+
+match_outdev:
+	if (!(info->bitmask & IPT_PHYSDEV_OP_OUT))
+		return MATCH;
+	outdev = nf_bridge->physoutdev ?
+		 nf_bridge->physoutdev->name : nulldevname;
+	for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) {
+		ret |= (((const unsigned long *)outdev)[i]
+			^ ((const unsigned long *)info->physoutdev)[i])
+			& ((const unsigned long *)info->out_mask)[i];
+	}
+
+	return (ret != 0) ^ !(info->invert & IPT_PHYSDEV_OP_OUT);
+}
+
+static int
+checkentry(const char *tablename,
+		       const struct ipt_ip *ip,
+		       void *matchinfo,
+		       unsigned int matchsize,
+		       unsigned int hook_mask)
+{
+	const struct ipt_physdev_info *info = matchinfo;
+
+	if (matchsize != IPT_ALIGN(sizeof(struct ipt_physdev_info)))
+		return 0;
+	if (!(info->bitmask & IPT_PHYSDEV_OP_MASK) ||
+	    info->bitmask & ~IPT_PHYSDEV_OP_MASK)
+		return 0;
+	return 1;
+}
+
+static struct ipt_match physdev_match = {
+	.name		= "physdev",
+	.match		= &match,
+	.checkentry	= &checkentry,
+	.me		= THIS_MODULE,
+};
+
+static int __init init(void)
+{
+	return ipt_register_match(&physdev_match);
+}
+
+static void __exit fini(void)
+{
+	ipt_unregister_match(&physdev_match);
+}
+
+module_init(init);
+module_exit(fini);
+MODULE_LICENSE("GPL");
+EXPORT_NO_SYMBOLS;
--- /dev/null	Thu Aug 24 11:00:32 2000
+++ linux-2.4.21-ebt-brnf-3/include/linux/netfilter_ipv4/ipt_physdev.h	Fri Aug  8 01:09:06 2003
@@ -0,0 +1,24 @@
+#ifndef _IPT_PHYSDEV_H
+#define _IPT_PHYSDEV_H
+
+#ifdef __KERNEL__
+#include <linux/if.h>
+#endif
+
+#define IPT_PHYSDEV_OP_IN		0x01
+#define IPT_PHYSDEV_OP_OUT		0x02
+#define IPT_PHYSDEV_OP_BRIDGED		0x04
+#define IPT_PHYSDEV_OP_ISIN		0x08
+#define IPT_PHYSDEV_OP_ISOUT		0x10
+#define IPT_PHYSDEV_OP_MASK		(0x20 - 1)
+
+struct ipt_physdev_info {
+	u_int8_t invert;
+	u_int8_t bitmask;
+	char physindev[IFNAMSIZ];
+	char in_mask[IFNAMSIZ];
+	char physoutdev[IFNAMSIZ];
+	char out_mask[IFNAMSIZ];
+};
+
+#endif /*_IPT_PHYSDEV_H*/