[BRIDGE]: bridge-nf, map IPv4 hooks onto bridge hooks.

include/linux/netfilter.h

@@ -117,17 +117,23 @@ extern struct list_head nf_hooks[NPROTO][NF_MAX_HOOKS];
 /* 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, 

include/linux/netfilter_bridge.h

@@ -6,6 +6,7 @@
 
 #include <linux/config.h>
 #include <linux/netfilter.h>
+#include <asm/atomic.h>
 
 /* Bridge Hooks */
 /* After promisc drops, checksum checks. */
@@ -22,14 +23,39 @@
 #define NF_BR_BROUTING		5
 #define NF_BR_NUMHOOKS		6
 
+#define BRNF_PKT_TYPE			0x01
+#define BRNF_BRIDGED_DNAT		0x02
+#define BRNF_DONT_TAKE_PARENT		0x04
+
 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_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,
 };
 
+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

include/linux/netfilter_ipv4.h

@@ -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,

include/linux/skbuff.h

@@ -96,6 +96,17 @@ 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 {
@@ -166,6 +177,7 @@ struct skb_shared_info {
  *	@nfcache: Cache info
  *	@nfct: Associated connection, if any
  *	@nf_debug: Netfilter debugging
+ *	@nf_bridge: Saved data about a bridged frame - see br_netfilter.c
  *	@tc_index: Traffic control index
  */
 
@@ -236,6 +248,9 @@ 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;
+#endif
 #endif /* CONFIG_NETFILTER */
 #if defined(CONFIG_HIPPI)
 	union {
@@ -1146,6 +1161,20 @@ static inline void 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__ */

net/bridge/Makefile

@@ -9,6 +9,11 @@ obj-$(CONFIG_BRIDGE) += bridge.o
 bridge-objs	:= br.o br_device.o br_fdb.o br_forward.o br_if.o br_input.o \
 			br_ioctl.o br_notify.o br_stp.o br_stp_bpdu.o \
 			br_stp_if.o br_stp_timer.o
+
+ifeq ($(CONFIG_NETFILTER),y)
+bridge-objs	+= br_netfilter.o
+endif
+
 obj-$(CONFIG_BRIDGE_NF_EBTABLES) += netfilter/
 
 include $(TOPDIR)/Rules.make

net/bridge/br.c

@@ -45,6 +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)
@@ -63,6 +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);
 

net/bridge/br_forward.c

@@ -30,18 +30,23 @@ static inline int should_deliver(struct net_bridge_port *p, struct sk_buff *skb)
 	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;
 }
@@ -53,7 +58,7 @@ static void __br_deliver(struct net_bridge_port *to, struct sk_buff *skb)
 	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)
@@ -64,7 +69,7 @@ static void __br_forward(struct net_bridge_port *to, struct sk_buff *skb)
 	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 */

net/bridge/br_input.c

@@ -49,7 +49,7 @@ static void br_pass_frame_up(struct net_bridge *br, struct sk_buff *skb)
 			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;

net/bridge/br_private.h

@@ -144,8 +144,10 @@ extern void br_fdb_insert(struct net_bridge *br,
 /* 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);
@@ -166,6 +168,7 @@ extern void br_get_port_ifindices(struct net_bridge *br,
 			   int *ifindices);
 
 /* br_input.c */
+extern int br_handle_frame_finish(struct sk_buff *skb);
 extern int br_handle_frame(struct sk_buff *skb);
 
 /* br_ioctl.c */
@@ -177,6 +180,10 @@ extern int br_ioctl(struct net_bridge *br,
 	     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);
 extern struct net_bridge_port *br_get_port(struct net_bridge *br,

net/core/netfilter.c

@@ -342,10 +342,15 @@ static unsigned int nf_iterate(struct list_head *head,
 			       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;
@@ -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);
@@ -435,11 +444,24 @@ static void nf_queue(struct sk_buff *skb,
 	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 hook, struct sk_buff *skb,
 
 	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);
@@ -530,7 +553,7 @@ void nf_reinject(struct sk_buff *skb, struct nf_info *info,
 		verdict = nf_iterate(&nf_hooks[info->pf][info->hook],
 				     &skb, info->hook, 
 				     info->indev, info->outdev, &elem,
-				     info->okfn);
+				     info->okfn, INT_MIN);
 	}
 
 	switch (verdict) {

net/core/skbuff.c

@@ -248,6 +248,9 @@ static inline void skb_headerinit(void *p, kmem_cache_t *cache,
 #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;
@@ -327,6 +330,9 @@ 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);
@@ -392,6 +398,9 @@ struct sk_buff *skb_clone(struct sk_buff *skb, int gfp_mask)
 #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);
@@ -404,6 +413,9 @@ struct sk_buff *skb_clone(struct sk_buff *skb, int gfp_mask)
 	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;
 }
@@ -438,6 +450,10 @@ static void copy_skb_header(struct sk_buff *new, const struct sk_buff *old)
 #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
 	new->tc_index	= old->tc_index;

net/ipv4/ip_output.c

@@ -402,6 +402,10 @@ static void ip_copy_metadata(struct sk_buff *to, struct sk_buff *from)
 	/* Connection association is same as pre-frag packet */
 	to->nfct = from->nfct;
 	nf_conntrack_get(to->nfct);
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+	to->nf_bridge = from->nf_bridge;
+	nf_bridge_get(to->nf_bridge);
+#endif
 #ifdef CONFIG_NETFILTER_DEBUG
 	to->nf_debug = from->nf_debug;
 #endif

net/ipv4/netfilter/ipt_LOG.c

@@ -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=");