[BRIDGE]: Add Ethernet bridge tables support.

MAINTAINERS

@@ -531,6 +531,14 @@ M:	mike@i-Connect.Net
 L:	linux-eata@i-connect.net, linux-scsi@vger.kernel.org
 S:	Maintained
 
+EBTABLES
+P:	Bart De Schuymer
+M:	bart.de.schuymer@pandora.be
+L:	ebtables-user@lists.sourceforge.net
+L:	ebtables-devel@lists.sourceforge.net
+W:	http://ebtables.sourceforge.net/
+S:	Maintained
+
 EEPRO100 NETWORK DRIVER
 P:	Andrey V. Savochkin
 M:	saw@saw.sw.com.sg

include/linux/if_bridge.h

@@ -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
 

include/linux/netfilter_bridge.h

@@ -18,7 +18,18 @@
 #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
 
+enum nf_br_hook_priorities {
+	NF_BR_PRI_FIRST = INT_MIN,
+	NF_BR_PRI_FILTER_BRIDGED = -200,
+	NF_BR_PRI_FILTER_OTHER = 200,
+	NF_BR_PRI_NAT_DST_BRIDGED = -300,
+	NF_BR_PRI_NAT_DST_OTHER = 100,
+	NF_BR_PRI_NAT_SRC = 300,
+	NF_BR_PRI_LAST = INT_MAX,
+};
 
 #endif

net/Config.in

@@ -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

net/bridge/Makefile

@@ -2,10 +2,13 @@
 # Makefile for the IEEE 802.1d ethernet bridging layer.
 #
 
+export-objs := br.o
+
 obj-$(CONFIG_BRIDGE) += bridge.o
 
 bridge-objs	:= 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
+obj-$(CONFIG_BRIDGE_NF_EBTABLES) += netfilter/
 
 include $(TOPDIR)/Rules.make

net/bridge/br.c

@@ -28,6 +28,8 @@
 #include "../atm/lec.h"
 #endif
 
+int (*br_should_route_hook) (struct sk_buff **pskb) = NULL;
+
 void br_dec_use_count()
 {
 	MOD_DEC_USE_COUNT;
@@ -74,6 +76,8 @@ static void __exit br_deinit(void)
 #endif
 }
 
+EXPORT_SYMBOL(br_should_route_hook);
+
 module_init(br_init)
 module_exit(br_deinit)
 MODULE_LICENSE("GPL");

net/bridge/br_forward.c

@@ -49,6 +49,9 @@ static int __br_forward_finish(struct sk_buff *skb)
 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);
 }

net/bridge/br_input.c

@@ -24,6 +24,9 @@ unsigned char bridge_ula[6] = { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 };
 
 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;
@@ -112,7 +115,7 @@ static int br_handle_frame_finish(struct sk_buff *skb)
 	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 +149,29 @@ 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))
+			return -1;
+
 		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;
 	}
 
 	kfree_skb(skb);
 	read_unlock(&br->lock);
+	return 0;
 }

net/bridge/br_private.h

@@ -166,7 +166,7 @@ extern void br_get_port_ifindices(struct net_bridge *br,
 			   int *ifindices);
 
 /* br_input.c */
-extern void br_handle_frame(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));

net/bridge/netfilter/Config.help

+CONFIG_BRIDGE_EBT
+  ebtables is an extendable frame filtering system for the Linux
+  Ethernet bridge. Its usage and implementation is very similar to that
+  of iptables.
+  The difference is that ebtables works on the Link Layer, while iptables
+  works on the Network Layer. ebtables can filter all frames that come
+  into contact with a logical bridge device.
+  Apart from filtering, ebtables also allows MAC source and destination
+  alterations (we call it MAC SNAT and MAC DNAT) and also provides
+  functionality for making Linux a brouter.
+
+  If you want to compile it as a module, say M here and read
+  <file:Documentation/modules.txt>.  If unsure, say `N'.
+
+CONFIG_BRIDGE_EBT_T_FILTER
+  The ebtables filter table is used to define frame filtering rules at
+  local input, forwarding and local output. See the man page for
+  ebtables(8).
+
+  If you want to compile it as a module, say M here and read
+  <file:Documentation/modules.txt>.  If unsure, say `N'.
+
+CONFIG_BRIDGE_EBT_T_NAT
+  The ebtables nat table is used to define rules that alter the MAC
+  source address (MAC SNAT) or the MAC destination address (MAC DNAT).
+  See the man page for ebtables(8).
+
+  If you want to compile it as a module, say M here and read
+  <file:Documentation/modules.txt>.  If unsure, say `N'.
+
+CONFIG_BRIDGE_EBT_BROUTE
+  The ebtables broute table is used to define rules that decide between
+  bridging and routing frames, giving Linux the functionality of a
+  brouter. See the man page for ebtables(8) and examples on the ebtables
+  website.
+
+  If you want to compile it as a module, say M here and read
+  <file:Documentation/modules.txt>.  If unsure, say `N'.
+
+CONFIG_BRIDGE_EBT_LOG
+  This option adds the log target, that you can use in any rule in
+  any ebtables table. It records the frame header to the syslog.
+
+  If you want to compile it as a module, say M here and read
+  <file:Documentation/modules.txt>.  If unsure, say `N'.
+
+CONFIG_BRIDGE_EBT_IPF
+  This option adds the IP match, which allows basic IP header field
+  filtering.
+
+  If you want to compile it as a module, say M here and read
+  <file:Documentation/modules.txt>.  If unsure, say `N'.
+
+CONFIG_BRIDGE_EBT_ARPF
+  This option adds the ARP match, which allows ARP and RARP header field
+  filtering.
+
+  If you want to compile it as a module, say M here and read
+  <file:Documentation/modules.txt>.  If unsure, say `N'.
+
+CONFIG_BRIDGE_EBT_VLANF
+  This option adds the 802.1Q vlan match, which allows the filtering of
+  802.1Q vlan fields.
+
+  If you want to compile it as a module, say M here and read
+  <file:Documentation/modules.txt>.  If unsure, say `N'.
+
+CONFIG_BRIDGE_EBT_MARKF
+  This option adds the mark match, which allows matching frames based on
+  the 'nfmark' value in the frame. This can be set by the mark target.
+  This value is the same as the one used in the iptables mark match and
+  target.
+
+  If you want to compile it as a module, say M here and read
+  <file:Documentation/modules.txt>.  If unsure, say `N'.
+
+CONFIG_BRIDGE_EBT_SNAT
+  This option adds the MAC SNAT target, which allows altering the MAC
+  source address of frames.
+
+  If you want to compile it as a module, say M here and read
+  <file:Documentation/modules.txt>.  If unsure, say `N'.
+
+CONFIG_BRIDGE_EBT_DNAT
+  This option adds the MAC DNAT target, which allows altering the MAC
+  destination address of frames.
+
+  If you want to compile it as a module, say M here and read
+  <file:Documentation/modules.txt>.  If unsure, say `N'.
+
+CONFIG_BRIDGE_EBT_REDIRECT
+  This option adds the MAC redirect target, which allows altering the MAC
+  destination address of a frame to that of the device it arrived on.
+
+  If you want to compile it as a module, say M here and read
+  <file:Documentation/modules.txt>.  If unsure, say `N'.
+
+CONFIG_BRIDGE_EBT_MARK_T
+  This option adds the mark target, which allows marking frames by
+  setting the 'nfmark' value in the frame.
+  This value is the same as the one used in the iptables mark match and
+  target.
+
+  If you want to compile it as a module, say M here and read
+  <file:Documentation/modules.txt>.  If unsure, say `N'.

net/bridge/netfilter/Config.in

+#
+# 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 (EXPERIMENTAL)' CONFIG_BRIDGE_EBT_VLANF $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
+

net/bridge/netfilter/Makefile

+#
+# Makefile for the netfilter modules for Link Layer filtering on a bridge.
+#
+
+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-$(CONFIG_BRIDGE_EBT_LOG) += ebt_log.o
+obj-$(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

net/bridge/netfilter/ebt_arp.c

+/*
+ *  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/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;
+		}
+	}
+	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 != 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);
+MODULE_LICENSE("GPL");

net/bridge/netfilter/ebt_dnat.c

+/*
+ *  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 != 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);
+MODULE_LICENSE("GPL");

net/bridge/netfilter/ebt_ip.c

+/*
+ *  ebt_ip
+ *
+ *	Authors:
+ *	Bart De Schuymer <bart.de.schuymer@pandora.be>
+ *
+ *  April, 2002
+ *
+ */
+
+#include <linux/netfilter_bridge/ebtables.h>
+#include <linux/netfilter_bridge/ebt_ip.h>
+#include <linux/ip.h>
+#include <linux/module.h>
+
+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 && FWINV(info->protocol !=
+	   ((*skb).nh.iph)->protocol, EBT_IP_PROTO))
+		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 != 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;
+	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);
+MODULE_LICENSE("GPL");

net/bridge/netfilter/ebt_log.c

+/*
+ *  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/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 != 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;
+}
+
+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 : "");
+
+	if (skb->dev->hard_header_len) {
+		int i;
+		unsigned char *p = (skb->mac.ethernet)->h_source;
+
+		printk("MAC source = ");
+		for (i = 0; i < ETH_ALEN; i++,p++)
+			printk("%02x%c", *p, i == ETH_ALEN - 1 ? ' ':':');
+		printk("MAC dest = ");
+		p = (skb->mac.ethernet)->h_dest;
+		for (i = 0; i < ETH_ALEN; i++,p++)
+			printk("%02x%c", *p, i == ETH_ALEN - 1 ? ' ':':');
+	}
+	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 ((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));
+	}
+	printk("\n");
+	spin_unlock_bh(&ebt_log_lock);
+}
+
+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);
+MODULE_LICENSE("GPL");

net/bridge/netfilter/ebt_mark.c

+/*
+ *  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 != 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);
+MODULE_LICENSE("GPL");

net/bridge/netfilter/ebt_mark_m.c

+/*
+ *  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 != 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);
+MODULE_LICENSE("GPL");

net/bridge/netfilter/ebt_redirect.c

+/*
+ *  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 != 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);
+MODULE_LICENSE("GPL");

net/bridge/netfilter/ebt_snat.c

+/*
+ *  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 != 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);
+MODULE_LICENSE("GPL");

net/bridge/netfilter/ebtable_broute.c

+/*
+ *  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);
+MODULE_LICENSE("GPL");

net/bridge/netfilter/ebtable_filter.c

+/*
+ *  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);
+MODULE_LICENSE("GPL");

net/bridge/netfilter/ebtable_nat.c

+/*
+ *  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);
+MODULE_LICENSE("GPL");

net/core/dev.c

@@ -1397,7 +1397,7 @@ void net_call_rx_atomic(void (*fn)(void))
 }
 
 #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,
@@ -1414,7 +1414,6 @@ static __inline__ int handle_bridge(struct sk_buff *skb,
 		}
 	}
 
-	br_handle_frame_hook(skb);
 	return ret;
 }
 
@@ -1475,7 +1474,12 @@ int netif_receive_skb(struct sk_buff *skb)
 
 #if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
 	if (skb->dev->br_port && br_handle_frame_hook) {
-		return handle_bridge(skb, pt_prev);
+		int ret;
+
+		ret = handle_bridge(skb, pt_prev);
+		if (br_handle_frame_hook(skb) == 0)
+			return ret;
+		pt_prev = NULL;
 	}
 #endif