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[PATCH] ebtables - Ethernet bridge tables, for 2.5.34

To: netdev@xxxxxxxxxxx, linux-net@xxxxxxxxxxxxxxx
Subject: [PATCH] ebtables - Ethernet bridge tables, for 2.5.34
From: Bart De Schuymer <bart.de.schuymer@xxxxxxxxxx>
Date: Thu, 12 Sep 2002 19:07:12 +0200
Sender: netdev-bounce@xxxxxxxxxxx
Hello list,

I sent this message to lkml too, but without the actual patch. I hope I'm 
allowed to send the full patch here. It's quite large.

Ebtables is a project similar to iptables, but working on the bridge netfilter 
hooks. It allows for a basic transparent firewall, making a brouter and doing 
MAC source address and destination address manipulation. The firewall part 
has currently modules for basic IP filtering, 802.1q filtering, ARP 
filtering, logging and a mark match/target.
Ebtables has been under development for over 1.5 year and has more than 100
users, I think.
You can also download the patch here:
http://users.pandora.be/bart.de.schuymer/ebtables/v2.0/ebtables-v2.0_vs_2.5.34.diff
http://users.pandora.be/bart.de.schuymer/ebtables/v2.0/ebtables-v2.0_vs_2.5.34.diff.gz

For more information, see
http://users.pandora.be/bart.de.schuymer/ebtables/
There is an ebtables hacking howto, some basic examples and some real life
examples from users. And ofcourse the userspace program.

This is the first time I'm submitting a large patch, so feel free to rant if 
I'm doing something wrong... Here it goes:

ebtables-v2.0 - 11 September 2002

Bart De Schuymer
****** Add ebtables project info

--- linux-2.5.34/MAINTAINERS    Mon Sep  9 19:35:13 2002
+++ linux-2.5.34-ebtables/MAINTAINERS   Wed Sep 11 23:06:55 2002
@@ -531,6 +531,14 @@ M: mike@xxxxxxxxxxxxx
 L:     linux-eata@xxxxxxxxxxxxx, linux-scsi@xxxxxxxxxxxxxxx
 S:     Maintained
 
+EBTABLES
+P:     Bart De Schuymer
+M:     bart.de.schuymer@xxxxxxxxxx
+L:     ebtables-user@xxxxxxxxxxxxxxxxxxxxx
+L:     ebtables-devel@xxxxxxxxxxxxxxxxxxxxx
+W:     http://ebtables.sourceforge.net/
+S:     Maintained
+
 EEPRO100 NETWORK DRIVER
 P:     Andrey V. Savochkin
 M:     saw@xxxxxxxxxxxxx

****** Clear nf_debug, we will be dealing with different netfilter hooks:
       the bridge hooks.

--- linux-2.5.34/net/bridge/br_forward.c        Mon Sep  9 19:35:07 2002
+++ linux-2.5.34-ebtables/net/bridge/br_forward.c       Wed Sep 11 23:06:55 2002
@@ -49,6 +49,9 @@ 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);
 }

****** modification for brouter support

--- linux-2.5.34/net/bridge/br_private.h        Mon Sep  9 19:35:05 2002
+++ linux-2.5.34-ebtables/net/bridge/br_private.h       Wed Sep 11 23:06:55 2002
@@ -166,7 +166,7 @@ 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(struct sk_buff *skb);
 
 /* br_ioctl.c */
 extern void br_call_ioctl_atomic(void (*fn)(void));

****** modification for brouter support

--- linux-2.5.34/include/linux/if_bridge.h      Mon Sep  9 19:35:11 2002
+++ linux-2.5.34-ebtables/include/linux/if_bridge.h     Wed Sep 11 23:06:55 2002
@@ -102,8 +102,13 @@ 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);
+#if defined(CONFIG_BRIDGE_EBT_BROUTE) || \
+    defined(CONFIG_BRIDGE_EBT_BROUTE_MODULE)
+extern unsigned int (*broute_decision) (unsigned int hook, struct sk_buff 
**pskb,
+   const struct net_device *in, const struct net_device *out,
+   int (*okfn)(struct sk_buff *));
+#endif
 #endif
 
 #endif

****** modification for brouter support
       br_handle_frame_hook return non-zero if the frame has to be routed,
       else the frame has been bridged.

--- linux-2.5.34/net/core/dev.c Mon Sep  9 19:35:12 2002
+++ linux-2.5.34-ebtables/net/core/dev.c        Wed Sep 11 23:06:55 2002
@@ -1395,7 +1395,7 @@ 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,
@@ -1412,7 +1412,6 @@ static __inline__ int handle_bridge(stru
                }
        }
 
-       br_handle_frame_hook(skb);
        return ret;
 }
 
@@ -1473,7 +1472,11 @@ int netif_receive_skb(struct sk_buff *sk
 
 #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;
        }
 #endif
 
****** modification for brouter support + clear nf_debug
       br_handle_frame_hook calls broute_decision(), which traverses
       the ebtables brouting table to get the decision to bridge or route
       the frame. Return value -1 means route, 0 means the frame has been
       bridged.

--- linux-2.5.34/net/bridge/br_input.c  Mon Sep  9 19:35:06 2002
+++ linux-2.5.34-ebtables/net/bridge/br_input.c Wed Sep 11 23:06:55 2002
@@ -19,11 +19,18 @@
 #include <linux/if_bridge.h>
 #include <linux/netfilter_bridge.h>
 #include "br_private.h"
+#if defined(CONFIG_BRIDGE_EBT_BROUTE) || \
+    defined(CONFIG_BRIDGE_EBT_BROUTE_MODULE)
+#include <linux/netfilter.h>
+#endif
 
 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 +119,7 @@ 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 +153,32 @@ void br_handle_frame(struct sk_buff *skb
                goto handle_special_frame;
 
        if (p->state == BR_STATE_FORWARDING) {
+#if defined(CONFIG_BRIDGE_EBT_BROUTE) || \
+    defined(CONFIG_BRIDGE_EBT_BROUTE_MODULE)
+               if (broute_decision && broute_decision(NF_BR_BROUTING, &skb,
+                  skb->dev, NULL, NULL) == NF_DROP)
+                       return -1;
+#endif
                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;
 }

****** broute_decision is defined here.

--- linux-2.5.34/net/bridge/br.c        Mon Sep  9 19:35:04 2002
+++ linux-2.5.34-ebtables/net/bridge/br.c       Wed Sep 11 23:06:55 2002
@@ -28,6 +28,14 @@
 #include "../atm/lec.h"
 #endif
 
+#if defined(CONFIG_BRIDGE_EBT_BROUTE) || \
+    defined(CONFIG_BRIDGE_EBT_BROUTE_MODULE)
+unsigned int (*broute_decision) (unsigned int hook, struct sk_buff **pskb,
+                        const struct net_device *in,
+                        const struct net_device *out,
+                        int (*okfn)(struct sk_buff *)) = NULL;
+#endif
+
 void br_dec_use_count()
 {
        MOD_DEC_USE_COUNT;
@@ -73,6 +81,11 @@ static void __exit br_deinit(void)
        br_fdb_put_hook = NULL;
 #endif
 }
+
+#if defined(CONFIG_BRIDGE_EBT_BROUTE) || \
+    defined(CONFIG_BRIDGE_EBT_BROUTE_MODULE)
+EXPORT_SYMBOL(broute_decision);
+#endif
 
 module_init(br_init)
 module_exit(br_deinit)

****** br.o may have to export broute_decision.
       Add the bridge/netfilter directory.

--- linux-2.5.34/net/bridge/Makefile    Mon Sep  9 19:35:21 2002
+++ linux-2.5.34-ebtables/net/bridge/Makefile   Wed Sep 11 23:06:55 2002
@@ -2,10 +2,17 @@
 # Makefile for the IEEE 802.1d ethernet bridging layer.
 #
 
+ifneq ($(CONFIG_BRIDGE_EBT_BROUTE),n)
+ifneq ($(CONFIG_BRIDGE_EBT_BROUTE),)
+export-objs := br.o
+endif
+endif
+
 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_EBT) += netfilter/
 
 include $(TOPDIR)/Rules.make

****** Add the NF_BR_BROUTING "hook"

--- linux-2.5.34/include/linux/netfilter_bridge.h       Mon Sep  9 19:35:12 2002
+++ linux-2.5.34-ebtables/include/linux/netfilter_bridge.h      Wed Sep 11 
23:06:55 
2002
@@ -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

****** Include the ebtables Config.in

--- linux-2.5.34/net/Config.in  Mon Sep  9 19:35:05 2002
+++ linux-2.5.34-ebtables/net/Config.in Wed Sep 11 23:06:55 2002
@@ -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

****** Now follow all the new files, without much comment.
       ebtables is modular like iptables, currently there are 3 tables:
       broute, nat and filter. There are some mark modules and target
       modules too. Also one watcher module, the log module.

--- /dev/null   Thu Aug 24 11:00:32 2000
+++ linux-2.5.34-ebtables/net/bridge/netfilter/Makefile Wed Sep 11 23:06:55 
2002
@@ -0,0 +1,20 @@
+#
+# Makefile for the netfilter modules for Link Layer filtering on a bridge.
+#
+
+export-objs := ebtables.o
+
+obj-$(CONFIG_BRIDGE_EBT) += ebtables.o
+obj-$(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
--- /dev/null   Thu Aug 24 11:00:32 2000
+++ linux-2.5.34-ebtables/net/bridge/netfilter/Config.in        Wed Sep 11 
23:06:55 
2002
@@ -0,0 +1,17 @@
+#
+# Bridge netfilter configuration
+#
+dep_tristate '  Bridge: ebtables' CONFIG_BRIDGE_EBT $CONFIG_BRIDGE
+dep_tristate '    ebt: filter table support' CONFIG_BRIDGE_EBT_T_FILTER 
$CONFIG_BRIDGE_EBT
+dep_tristate '    ebt: nat table support' CONFIG_BRIDGE_EBT_T_NAT 
$CONFIG_BRIDGE_EBT
+dep_tristate '    ebt: broute table support' CONFIG_BRIDGE_EBT_BROUTE 
$CONFIG_BRIDGE_EBT
+dep_tristate '    ebt: log support' CONFIG_BRIDGE_EBT_LOG $CONFIG_BRIDGE_EBT
+dep_tristate '    ebt: IP filter support' CONFIG_BRIDGE_EBT_IPF 
$CONFIG_BRIDGE_EBT
+dep_tristate '    ebt: ARP filter support' CONFIG_BRIDGE_EBT_ARPF 
$CONFIG_BRIDGE_EBT
+dep_tristate '    ebt: 802.1Q VLAN filter support (EXPERIMENTAL)' 
CONFIG_BRIDGE_EBT_VLANF $CONFIG_BRIDGE_EBT
+dep_tristate '    ebt: mark filter support' CONFIG_BRIDGE_EBT_MARKF 
$CONFIG_BRIDGE_EBT
+dep_tristate '    ebt: snat target support' CONFIG_BRIDGE_EBT_SNAT 
$CONFIG_BRIDGE_EBT
+dep_tristate '    ebt: dnat target support' CONFIG_BRIDGE_EBT_DNAT 
$CONFIG_BRIDGE_EBT
+dep_tristate '    ebt: redirect target support' CONFIG_BRIDGE_EBT_REDIRECT 
$CONFIG_BRIDGE_EBT
+dep_tristate '    ebt: mark target support' CONFIG_BRIDGE_EBT_MARK_T 
$CONFIG_BRIDGE_EBT
+
--- /dev/null   Thu Aug 24 11:00:32 2000
+++ linux-2.5.34-ebtables/net/bridge/netfilter/Config.help      Wed Sep 11 
23:06:55 
2002
@@ -0,0 +1,105 @@
+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'.
--- /dev/null   Thu Aug 24 11:00:32 2000
+++ linux-2.5.34-ebtables/net/bridge/netfilter/ebtable_filter.c Wed Sep 11 
23:06:55 2002
@@ -0,0 +1,90 @@
+/*
+ *  ebtable_filter
+ *
+ *     Authors:
+ *     Bart De Schuymer <bart.de.schuymer@xxxxxxxxxx>
+ *
+ *  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-2.5.34-ebtables/net/bridge/netfilter/ebtable_nat.c    Wed Sep 11 
23:06:55 2002
@@ -0,0 +1,96 @@
+/*
+ *  ebtable_nat
+ *
+ *     Authors:
+ *     Bart De Schuymer <bart.de.schuymer@xxxxxxxxxx>
+ *
+ *  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-2.5.34-ebtables/net/bridge/netfilter/ebtable_broute.c Wed Sep 11 
23:06:55 2002
@@ -0,0 +1,75 @@
+/*
+ *  ebtable_broute
+ *
+ *     Authors:
+ *     Bart De Schuymer <bart.de.schuymer@xxxxxxxxxx>
+ *
+ *  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 unsigned int
+ebt_broute(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, &broute_table);
+}
+
+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);
+       // in br_input.c, br_handle_frame() wants to call broute_decision()
+       broute_decision = ebt_broute;
+       br_write_unlock_bh(BR_NETPROTO_LOCK);
+       return ret;
+}
+
+static void __exit fini(void)
+{
+       br_write_lock_bh(BR_NETPROTO_LOCK);
+       broute_decision = 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-2.5.34-ebtables/net/bridge/netfilter/ebt_mark.c       Wed Sep 11 
23:06:55 
2002
@@ -0,0 +1,66 @@
+/*
+ *  ebt_mark
+ *
+ *     Authors:
+ *     Bart De Schuymer <bart.de.schuymer@xxxxxxxxxx>
+ *
+ *  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);
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
--- /dev/null   Thu Aug 24 11:00:32 2000
+++ linux-2.5.34-ebtables/net/bridge/netfilter/ebt_mark_m.c     Wed Sep 11 
23:06:55 2002
@@ -0,0 +1,61 @@
+/*
+ *  ebt_mark_m
+ *
+ *     Authors:
+ *     Bart De Schuymer <bart.de.schuymer@xxxxxxxxxx>
+ *
+ *  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);
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
--- /dev/null   Thu Aug 24 11:00:32 2000
+++ linux-2.5.34-ebtables/net/bridge/netfilter/ebt_redirect.c   Wed Sep 11 
23:06:55 2002
@@ -0,0 +1,71 @@
+/*
+ *  ebt_redirect
+ *
+ *     Authors:
+ *     Bart De Schuymer <bart.de.schuymer@xxxxxxxxxx>
+ *
+ *  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);
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
--- /dev/null   Thu Aug 24 11:00:32 2000
+++ linux-2.5.34-ebtables/net/bridge/netfilter/ebt_arp.c        Wed Sep 11 
23:06:55 
2002
@@ -0,0 +1,102 @@
+/*
+ *  ebt_arp
+ *
+ *     Authors:
+ *     Bart De Schuymer <bart.de.schuymer@xxxxxxxxxx>
+ *     Tim Gardner <timg@xxxxxxx>
+ *
+ *  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);
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
--- /dev/null   Thu Aug 24 11:00:32 2000
+++ linux-2.5.34-ebtables/net/bridge/netfilter/ebt_ip.c Wed Sep 11 23:06:55 
2002
@@ -0,0 +1,73 @@
+/*
+ *  ebt_ip
+ *
+ *     Authors:
+ *     Bart De Schuymer <bart.de.schuymer@xxxxxxxxxx>
+ *
+ *  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);
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
--- /dev/null   Thu Aug 24 11:00:32 2000
+++ linux-2.5.34-ebtables/net/bridge/netfilter/ebt_vlan.c       Wed Sep 11 
23:56:37 
2002
@@ -0,0 +1,318 @@
+/*
+ * Description: EBTables 802.1Q match extension kernelspace module.
+ * Authors: Nick Fedchik <nick@xxxxxxxxxxxxxx>
+ *          Bart De Schuymer <bart.de.schuymer@xxxxxxxxxx>
+ *    
+ * 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 "0.4 (" __DATE__ " " __TIME__ ")"
+
+MODULE_PARM (debug, "0-1b");
+MODULE_PARM_DESC (debug, "debug=1 is turn on debug messages");
+MODULE_AUTHOR ("Nick Fedchik <nick@xxxxxxxxxxxxxx>");
+MODULE_DESCRIPTION ("802.1Q match module (ebtables extension), v"
+                   MODULE_VERSION);
+MODULE_LICENSE ("GPL");
+
+
+#define DEBUG_MSG(...) if (debug) printk (KERN_DEBUG __FILE__ ":" 
__VA_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. This field allows the tagged frame to carry 
user_priority
+        * information across Bridged LANs in which individual LAN segments may 
be 
unable to signal
+        * priority information (e.g., 802.3/Ethernet segments). 
+        * The user_priority field is three bits in length, 
+        * interpreted as a binary number. The user_priority is therefore
+        * capable of representing eight priority levels, 0 through 7. 
+        * The use and interpretation of this field is defined in ISO/IEC 
15802-3.
+        * - Canonical Format Indicator (CFI). This field is used,
+        * in 802.3/Ethernet, to signal the presence or absence
+        * of a RIF field, and, in combination with the Non-canonical Format 
Indicator (NCFI) carried
+        * in the RIF, to signal the bit order of address information carried 
in the 
encapsulated
+        * frame. The Canonical Format Indicator (CFI) is a single bit flag 
value.
+        * - VLAN Identifier (VID). This field uniquely identifies the VLAN to
+        * which the frame belongs. The twelve-bit VLAN Identifier (VID) field 
+        * uniquely identify the VLAN to which the frame belongs. 
+        * The VID is encoded as an unsigned binary number. 
+        */
+       TCI = ntohs (frame->h_vlan_TCI);
+       id = TCI & 0xFFF;
+       prio = TCI >> 13;
+       encap = frame->h_vlan_encapsulated_proto;
+
+       /*
+        * First step is to check is null VLAN ID present
+        * in the parsed frame
+        */
+       if (!(id)) {
+               /*
+                * Checking VLAN Identifier (VID)
+                */
+               if (GET_BITMASK (EBT_VLAN_ID)) {        /* Is VLAN ID parsed? */
+                       EXIT_ON_MISMATCH (id, EBT_VLAN_ID);
+                       DEBUG_MSG
+                           ("matched rule id=%s%d for frame id=%d\n",
+                            INV_FLAG (EBT_VLAN_ID), info->id, id);
+               }
+       } else {
+               /*
+                * Checking user_priority
+                */
+               if (GET_BITMASK (EBT_VLAN_PRIO)) {      /* Is VLAN 
user_priority parsed? */
+                       EXIT_ON_MISMATCH (prio, EBT_VLAN_PRIO);
+                       DEBUG_MSG
+                           ("matched rule prio=%s%d for frame prio=%d\n",
+                            INV_FLAG (EBT_VLAN_PRIO), info->prio,
+                            prio);
+               }
+       }
+       /*
+        * Checking Encapsulated Proto (Length/Type) field
+        */
+       if (GET_BITMASK (EBT_VLAN_ENCAP)) {     /* Is VLAN Encap parsed? */
+               EXIT_ON_MISMATCH (encap, EBT_VLAN_ENCAP);
+               DEBUG_MSG ("matched encap=%s%2.4X for frame encap=%2.4X\n",
+                          INV_FLAG (EBT_VLAN_ENCAP),
+                          ntohs (info->encap), ntohs (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 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 != sizeof (struct ebt_vlan_info)) {
+               DEBUG_MSG
+                   ("params 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. Indicates that the tag header contains only 
user_priority information;
+        * no VLAN identifier is present in the frame. This VID value shall not 
be
+        * configured as a PVID, configured in any Filtering Database entry, or 
used 
in any
+        * Management operation.
+        * 
+        * 1 - The default Port VID (PVID) value used for classifying frames on 
ingress through a Bridge
+        * Port. The PVID value can be changed by management on a per-Port 
basis.
+        * 
+        * 0x0FFF - Reserved for implementation use. This VID value shall not 
be 
configured as a
+        * PVID or transmitted in a tag header.
+        * 
+        * The remaining values of VID are available for general use as VLAN 
identifiers.
+        * A Bridge may implement the ability to support less than the full 
range of 
VID values; 
+        * i.e., for a given implementation,
+        * an upper limit, N, is defined for the VID values supported, where N 
is 
less than or equal to 4094.
+        * All implementations shall support the use of all VID values in the 
range 
0 through their defined maximum
+        * VID, N.
+        * 
+        * For Linux, N = 4094.
+        */
+       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 > 4094) {  /* check if id > than (0x0FFE) 
*/
+                               DEBUG_MSG
+                                   ("vlan id %d is out of range (1-4094)\n",
+                                    info->id);
+                               return -EINVAL;
+                       }
+                       /*
+                        * Note: This is valid VLAN-tagged frame point.
+                        * Any value of user_priority are acceptable, but could 
be ignored
+                        * according to 802.1Q Std.
+                        */
+               } else {
+                       /*
+                        * if id=0 (null VLAN ID)  => Check for user_priority 
range 
+                        */
+                       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;
+                               }
+                       }
+                       /*
+                        * Note2: This is valid priority-tagged frame point
+                        * with null VID field.
+                        */
+               }
+       } else {                /* VLAN Id not set */
+               if (GET_BITMASK (EBT_VLAN_PRIO)) {      /* But user_priority is 
set - abnormal! 
*/
+                       info->id = 0;   /* Set null VID (case for 
Priority-tagged frames) */
+                       SET_BITMASK (EBT_VLAN_ID);      /* and set id flag */
+               }
+       }
+       /*
+        * Check for encapsulated proto range - it is possible to be any value 
for 
u_short range.
+        * When relaying a tagged frame between 802.3/Ethernet MACs, 
+        * a Bridge may adjust the padding field such that
+        * the minimum size of a transmitted tagged frame is 68 octets (7.2).
+        * 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 packet length %d is less than minimal %d\n",
+                            ntohs (info->encap), ETH_ZLEN);
+                       return -EINVAL;
+               }
+       }
+
+       /*
+        * Otherwise is all correct 
+        */
+       DEBUG_MSG ("802.1Q tagged frame checked (%s table, %d hook)\n",
+                  tablename, hooknr);
+       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.
+ * Called when module is loaded to kernelspace
+ */
+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
+ * Called when download module from kernelspace
+ */
+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-2.5.34-ebtables/net/bridge/netfilter/ebt_log.c        Wed Sep 11 
23:06:55 
2002
@@ -0,0 +1,100 @@
+/*
+ *  ebt_log
+ *
+ *     Authors:
+ *     Bart De Schuymer <bart.de.schuymer@xxxxxxxxxx>
+ *
+ *  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);
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
--- /dev/null   Thu Aug 24 11:00:32 2000
+++ linux-2.5.34-ebtables/net/bridge/netfilter/ebt_snat.c       Wed Sep 11 
23:06:55 
2002
@@ -0,0 +1,64 @@
+/*
+ *  ebt_snat
+ *
+ *     Authors:
+ *     Bart De Schuymer <bart.de.schuymer@xxxxxxxxxx>
+ *
+ *  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);
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
--- /dev/null   Thu Aug 24 11:00:32 2000
+++ linux-2.5.34-ebtables/net/bridge/netfilter/ebt_dnat.c       Wed Sep 11 
23:06:55 
2002
@@ -0,0 +1,65 @@
+/*
+ *  ebt_dnat
+ *
+ *     Authors:
+ *     Bart De Schuymer <bart.de.schuymer@xxxxxxxxxx>
+ *
+ *  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);
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
--- /dev/null   Thu Aug 24 11:00:32 2000
+++ linux-2.5.34-ebtables/net/bridge/netfilter/ebtables.c       Wed Sep 11 
23:06:55 
2002
@@ -0,0 +1,1484 @@
+/*
+ *  ebtables
+ *
+ *  Author:
+ *  Bart De Schuymer           <bart.de.schuymer@xxxxxxxxxx>
+ *
+ *  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,
+          smp_processor_id());
+       if (private->chainstack)
+               cs = private->chainstack[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 = (char *)chaininfo;
+       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++;
+
+               // 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
+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(NR_CPUS * sizeof(struct ebt_chainstack));
+               if (!newinfo->chainstack)
+                       return -ENOMEM;
+               for (i = 0; i < NR_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=mc²):
+       // - 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 < NR_CPUS; cpu++) {
+               counter_base = COUNTER_BASE(oldcounters, nentries, cpu);
+               for (i = 0; i < nentries; i++)
+                       counters[i].pcnt += counter_base[i].pcnt;
+       }
+}
+
+// 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) * NR_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 < NR_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 < NR_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) * NR_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 < NR_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 < NR_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;
+
+       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("Ebtables v2.0 registered");
+       return 0;
+}
+
+static void __exit fini(void)
+{
+       nf_unregister_sockopt(&ebt_sockopts);
+       printk("Ebtables v2.0 unregistered");
+}
+
+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-2.5.34-ebtables/include/linux/netfilter_bridge/ebtables.h     Wed Sep 
11 
23:06:55 2002
@@ -0,0 +1,358 @@
+/*
+ *  ebtables
+ *
+ *     Authors:
+ *     Bart De Schuymer                <bart.de.schuymer@xxxxxxxxxx>
+ *
+ *  ebtables.c,v 2.0, April, 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
+
+// [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)
+
+// 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
+
+// return values for match() functions
+#define EBT_MATCH 0
+#define EBT_NOMATCH 1
+
+struct ebt_counter
+{
+       uint64_t pcnt;
+};
+
+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];
+};
+
+// 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];
+};
+
+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];
+};
+
+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];
+};
+
+#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];
+};
+
+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;
+};
+
+#ifdef __KERNEL__
+
+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;
+};
+
+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-2.5.34-ebtables/include/linux/netfilter_bridge/ebt_arp.h      Wed Sep 
11 
23:06:55 2002
@@ -0,0 +1,26 @@
+#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_MASK (EBT_ARP_OPCODE | EBT_ARP_HTYPE | EBT_ARP_PTYPE | \
+   EBT_ARP_SRC_IP | EBT_ARP_DST_IP)
+#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;
+       uint8_t  bitmask;
+       uint8_t  invflags;
+};
+
+#endif
--- /dev/null   Thu Aug 24 11:00:32 2000
+++ linux-2.5.34-ebtables/include/linux/netfilter_bridge/ebt_ip.h       Wed Sep 
11 
23:06:55 2002
@@ -0,0 +1,24 @@
+#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_MASK (EBT_IP_SOURCE | EBT_IP_DEST | EBT_IP_TOS | EBT_IP_PROTO)
+#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;
+};
+
+#endif
--- /dev/null   Thu Aug 24 11:00:32 2000
+++ linux-2.5.34-ebtables/include/linux/netfilter_bridge/ebt_vlan.h     Wed Sep 
11 
23:06:55 2002
@@ -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-2.5.34-ebtables/include/linux/netfilter_bridge/ebt_log.h      Wed Sep 
11 
23:06:55 2002
@@ -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-2.5.34-ebtables/include/linux/netfilter_bridge/ebt_nat.h      Wed Sep 
11 
23:06:55 2002
@@ -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-2.5.34-ebtables/include/linux/netfilter_bridge/ebt_redirect.h Wed 
Sep 11 23:06:55 2002
@@ -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-2.5.34-ebtables/include/linux/netfilter_bridge/ebt_mark_m.h   Wed Sep 
11 23:06:55 2002
@@ -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-2.5.34-ebtables/include/linux/netfilter_bridge/ebt_mark_t.h   Wed Sep 
11 23:06:55 2002
@@ -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



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