--- /dev/null
+--- /dev/null
++++ b/drivers/net/imq.c
+@@ -0,0 +1,638 @@
++/*
++ * Pseudo-driver for the intermediate queue device.
++ *
++ * 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.
++ *
++ * Authors: Patrick McHardy, <kaber@trash.net>
++ *
++ * The first version was written by Martin Devera, <devik@cdi.cz>
++ *
++ * Credits: Jan Rafaj <imq2t@cedric.vabo.cz>
++ * - Update patch to 2.4.21
++ * Sebastian Strollo <sstrollo@nortelnetworks.com>
++ * - Fix "Dead-loop on netdevice imq"-issue
++ * Marcel Sebek <sebek64@post.cz>
++ * - Update to 2.6.2-rc1
++ *
++ * After some time of inactivity there is a group taking care
++ * of IMQ again: http://www.linuximq.net
++ *
++ *
++ * 2004/06/30 - New version of IMQ patch to kernels <=2.6.7
++ * including the following changes:
++ *
++ * - Correction of ipv6 support "+"s issue (Hasso Tepper)
++ * - Correction of imq_init_devs() issue that resulted in
++ * kernel OOPS unloading IMQ as module (Norbert Buchmuller)
++ * - Addition of functionality to choose number of IMQ devices
++ * during kernel config (Andre Correa)
++ * - Addition of functionality to choose how IMQ hooks on
++ * PRE and POSTROUTING (after or before NAT) (Andre Correa)
++ * - Cosmetic corrections (Norbert Buchmuller) (Andre Correa)
++ *
++ *
++ * 2005/12/16 - IMQ versions between 2.6.7 and 2.6.13 were
++ * released with almost no problems. 2.6.14-x was released
++ * with some important changes: nfcache was removed; After
++ * some weeks of trouble we figured out that some IMQ fields
++ * in skb were missing in skbuff.c - skb_clone and copy_skb_header.
++ * These functions are correctly patched by this new patch version.
++ *
++ * Thanks for all who helped to figure out all the problems with
++ * 2.6.14.x: Patrick McHardy, Rune Kock, VeNoMouS, Max CtRiX,
++ * Kevin Shanahan, Richard Lucassen, Valery Dachev (hopefully
++ * I didn't forget anybody). I apologize again for my lack of time.
++ *
++ *
++ * 2008/06/17 - 2.6.25 - Changed imq.c to use qdisc_run() instead
++ * of qdisc_restart() and moved qdisc_run() to tasklet to avoid
++ * recursive locking. New initialization routines to fix 'rmmod' not
++ * working anymore. Used code from ifb.c. (Jussi Kivilinna)
++ *
++ * 2008/08/06 - 2.6.26 - (JK)
++ * - Replaced tasklet with 'netif_schedule()'.
++ * - Cleaned up and added comments for imq_nf_queue().
++ *
++ * 2009/04/12
++ * - Add skb_save_cb/skb_restore_cb helper functions for backuping
++ * control buffer. This is needed because qdisc-layer on kernels
++ * 2.6.27 and newer overwrite control buffer. (Jussi Kivilinna)
++ * - Add better locking for IMQ device. Hopefully this will solve
++ * SMP issues. (Jussi Kivilinna)
++ * - Port to 2.6.27
++ * - Port to 2.6.28
++ * - Port to 2.6.29 + fix rmmod not working
++ *
++ * 2009/04/20 - (Jussi Kivilinna)
++ * - Use netdevice feature flags to avoid extra packet handling
++ * by core networking layer and possibly increase performance.
++ *
++ * 2009/09/26 - (Jussi Kivilinna)
++ * - Add imq_nf_reinject_lockless to fix deadlock with
++ * imq_nf_queue/imq_nf_reinject.
++ *
++ * 2009/12/08 - (Jussi Kivilinna)
++ * - Port to 2.6.32
++ * - Add check for skb->nf_queue_entry==NULL in imq_dev_xmit()
++ * - Also add better error checking for skb->nf_queue_entry usage
++ *
++ * 2010/02/25 - (Jussi Kivilinna)
++ * - Port to 2.6.33
++ *
++ * 2010/08/12 - (Jussi Kivilinna)
++ * - Port to 2.6.35
++ *
++ * Also, many thanks to pablo Sebastian Greco for making the initial
++ * patch and to those who helped the testing.
++ *
++ * More info at: http://www.linuximq.net/ (Andre Correa)
++ */
++
++#include <linux/module.h>
++#include <linux/kernel.h>
++#include <linux/moduleparam.h>
++#include <linux/list.h>
++#include <linux/skbuff.h>
++#include <linux/netdevice.h>
++#include <linux/etherdevice.h>
++#include <linux/rtnetlink.h>
++#include <linux/if_arp.h>
++#include <linux/netfilter.h>
++#include <linux/netfilter_ipv4.h>
++#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
++ #include <linux/netfilter_ipv6.h>
++#endif
++#include <linux/imq.h>
++#include <net/pkt_sched.h>
++#include <net/netfilter/nf_queue.h>
++
++static nf_hookfn imq_nf_hook;
++
++static struct nf_hook_ops imq_ingress_ipv4 = {
++ .hook = imq_nf_hook,
++ .owner = THIS_MODULE,
++ .pf = PF_INET,
++ .hooknum = NF_INET_PRE_ROUTING,
++#if defined(CONFIG_IMQ_BEHAVIOR_BA) || defined(CONFIG_IMQ_BEHAVIOR_BB)
++ .priority = NF_IP_PRI_MANGLE + 1
++#else
++ .priority = NF_IP_PRI_NAT_DST + 1
++#endif
++};
++
++static struct nf_hook_ops imq_egress_ipv4 = {
++ .hook = imq_nf_hook,
++ .owner = THIS_MODULE,
++ .pf = PF_INET,
++ .hooknum = NF_INET_POST_ROUTING,
++#if defined(CONFIG_IMQ_BEHAVIOR_AA) || defined(CONFIG_IMQ_BEHAVIOR_BA)
++ .priority = NF_IP_PRI_LAST
++#else
++ .priority = NF_IP_PRI_NAT_SRC - 1
++#endif
++};
++
++#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
++static struct nf_hook_ops imq_ingress_ipv6 = {
++ .hook = imq_nf_hook,
++ .owner = THIS_MODULE,
++ .pf = PF_INET6,
++ .hooknum = NF_INET_PRE_ROUTING,
++#if defined(CONFIG_IMQ_BEHAVIOR_BA) || defined(CONFIG_IMQ_BEHAVIOR_BB)
++ .priority = NF_IP6_PRI_MANGLE + 1
++#else
++ .priority = NF_IP6_PRI_NAT_DST + 1
++#endif
++};
++
++static struct nf_hook_ops imq_egress_ipv6 = {
++ .hook = imq_nf_hook,
++ .owner = THIS_MODULE,
++ .pf = PF_INET6,
++ .hooknum = NF_INET_POST_ROUTING,
++#if defined(CONFIG_IMQ_BEHAVIOR_AA) || defined(CONFIG_IMQ_BEHAVIOR_BA)
++ .priority = NF_IP6_PRI_LAST
++#else
++ .priority = NF_IP6_PRI_NAT_SRC - 1
++#endif
++};
++#endif
++
++#if defined(CONFIG_IMQ_NUM_DEVS)
++static unsigned int numdevs = CONFIG_IMQ_NUM_DEVS;
++#else
++static unsigned int numdevs = IMQ_MAX_DEVS;
++#endif
++
++static DEFINE_SPINLOCK(imq_nf_queue_lock);
++
++static struct net_device *imq_devs_cache[IMQ_MAX_DEVS];
++
++
++static struct net_device_stats *imq_get_stats(struct net_device *dev)
++{
++ return &dev->stats;
++}
++
++/* called for packets kfree'd in qdiscs at places other than enqueue */
++static void imq_skb_destructor(struct sk_buff *skb)
++{
++ struct nf_queue_entry *entry = skb->nf_queue_entry;
++
++ skb->nf_queue_entry = NULL;
++
++ if (entry) {
++ nf_queue_entry_release_refs(entry);
++ kfree(entry);
++ }
++
++ skb_restore_cb(skb); /* kfree backup */
++}
++
++/* locking not needed when called from imq_nf_queue */
++static void imq_nf_reinject_lockless(struct nf_queue_entry *entry,
++ unsigned int verdict)
++{
++ int status;
++
++ if (!entry->next_outfn) {
++ nf_reinject(entry, verdict);
++ return;
++ }
++
++ status = entry->next_outfn(entry, entry->next_queuenum);
++ if (status < 0) {
++ nf_queue_entry_release_refs(entry);
++ kfree_skb(entry->skb);
++ kfree(entry);
++ }
++}
++
++static void imq_nf_reinject(struct nf_queue_entry *entry, unsigned int verdict)
++{
++ int status;
++
++ if (!entry->next_outfn) {
++ spin_lock_bh(&imq_nf_queue_lock);
++ nf_reinject(entry, verdict);
++ spin_unlock_bh(&imq_nf_queue_lock);
++ return;
++ }
++
++ rcu_read_lock();
++ local_bh_disable();
++ status = entry->next_outfn(entry, entry->next_queuenum);
++ local_bh_enable();
++ if (status < 0) {
++ nf_queue_entry_release_refs(entry);
++ kfree_skb(entry->skb);
++ kfree(entry);
++ }
++
++ rcu_read_unlock();
++}
++
++static netdev_tx_t imq_dev_xmit(struct sk_buff *skb, struct net_device *dev)
++{
++ struct nf_queue_entry *entry = skb->nf_queue_entry;
++
++ skb->nf_queue_entry = NULL;
++ dev->trans_start = jiffies;
++
++ dev->stats.tx_bytes += skb->len;
++ dev->stats.tx_packets++;
++
++ if (entry == NULL) {
++ /* We don't know what is going on here.. packet is queued for
++ * imq device, but (probably) not by us.
++ *
++ * If this packet was not send here by imq_nf_queue(), then
++ * skb_save_cb() was not used and skb_free() should not show:
++ * WARNING: IMQ: kfree_skb: skb->cb_next:..
++ * and/or
++ * WARNING: IMQ: kfree_skb: skb->nf_queue_entry...
++ *
++ * However if this message is shown, then IMQ is somehow broken
++ * and you should report this to linuximq.net.
++ */
++
++ /* imq_dev_xmit is black hole that eats all packets, report that
++ * we eat this packet happily and increase dropped counters.
++ */
++
++ dev->stats.tx_dropped++;
++ dev_kfree_skb(skb);
++
++ return NETDEV_TX_OK;
++ }
++
++ skb_restore_cb(skb); /* restore skb->cb */
++
++ skb->imq_flags = 0;
++ skb->destructor = NULL;
++
++ imq_nf_reinject(entry, NF_ACCEPT);
++
++ return NETDEV_TX_OK;
++}
++
++static int imq_nf_queue(struct nf_queue_entry *entry, unsigned queue_num)
++{
++ struct net_device *dev;
++ struct sk_buff *skb_orig, *skb, *skb_shared;
++ struct Qdisc *q;
++ struct netdev_queue *txq;
++ int users, index;
++ int retval = -EINVAL;
++
++ index = entry->skb->imq_flags & IMQ_F_IFMASK;
++ if (unlikely(index > numdevs - 1)) {
++ if (net_ratelimit())
++ printk(KERN_WARNING
++ "IMQ: invalid device specified, highest is %u\n",
++ numdevs - 1);
++ retval = -EINVAL;
++ goto out;
++ }
++
++ /* check for imq device by index from cache */
++ dev = imq_devs_cache[index];
++ if (unlikely(!dev)) {
++ char buf[8];
++
++ /* get device by name and cache result */
++ snprintf(buf, sizeof(buf), "imq%d", index);
++ dev = dev_get_by_name(&init_net, buf);
++ if (!dev) {
++ /* not found ?!*/
++ BUG();
++ retval = -ENODEV;
++ goto out;
++ }
++
++ imq_devs_cache[index] = dev;
++ dev_put(dev);
++ }
++
++ if (unlikely(!(dev->flags & IFF_UP))) {
++ entry->skb->imq_flags = 0;
++ imq_nf_reinject_lockless(entry, NF_ACCEPT);
++ retval = 0;
++ goto out;
++ }
++ dev->last_rx = jiffies;
++
++ skb = entry->skb;
++ skb_orig = NULL;
++
++ /* skb has owner? => make clone */
++ if (unlikely(skb->destructor)) {
++ skb_orig = skb;
++ skb = skb_clone(skb, GFP_ATOMIC);
++ if (!skb) {
++ retval = -ENOMEM;
++ goto out;
++ }
++ entry->skb = skb;
++ }
++
++ skb->nf_queue_entry = entry;
++
++ dev->stats.rx_bytes += skb->len;
++ dev->stats.rx_packets++;
++
++ txq = dev_pick_tx(dev, skb);
++
++ q = rcu_dereference(txq->qdisc);
++ if (unlikely(!q->enqueue))
++ goto packet_not_eaten_by_imq_dev;
++
++ spin_lock_bh(qdisc_lock(q));
++
++ users = atomic_read(&skb->users);
++
++ skb_shared = skb_get(skb); /* increase reference count by one */
++ skb_save_cb(skb_shared); /* backup skb->cb, as qdisc layer will
++ overwrite it */
++ qdisc_enqueue_root(skb_shared, q); /* might kfree_skb */
++
++ if (likely(atomic_read(&skb_shared->users) == users + 1)) {
++ kfree_skb(skb_shared); /* decrease reference count by one */
++
++ skb->destructor = &imq_skb_destructor;
++
++ /* cloned? */
++ if (skb_orig)
++ kfree_skb(skb_orig); /* free original */
++
++ spin_unlock_bh(qdisc_lock(q));
++
++ /* schedule qdisc dequeue */
++ __netif_schedule(q);
++
++ retval = 0;
++ goto out;
++ } else {
++ skb_restore_cb(skb_shared); /* restore skb->cb */
++ skb->nf_queue_entry = NULL;
++ /* qdisc dropped packet and decreased skb reference count of
++ * skb, so we don't really want to and try refree as that would
++ * actually destroy the skb. */
++ spin_unlock_bh(qdisc_lock(q));
++ goto packet_not_eaten_by_imq_dev;
++ }
++
++packet_not_eaten_by_imq_dev:
++ /* cloned? restore original */
++ if (skb_orig) {
++ kfree_skb(skb);
++ entry->skb = skb_orig;
++ }
++ retval = -1;
++out:
++ return retval;
++}
++
++static struct nf_queue_handler nfqh = {
++ .name = "imq",
++ .outfn = imq_nf_queue,
++};
++
++static unsigned int imq_nf_hook(unsigned int hook, struct sk_buff *pskb,
++ const struct net_device *indev,
++ const struct net_device *outdev,
++ int (*okfn)(struct sk_buff *))
++{
++ if (pskb->imq_flags & IMQ_F_ENQUEUE)
++ return NF_QUEUE;
++
++ return NF_ACCEPT;
++}
++
++static int imq_close(struct net_device *dev)
++{
++ netif_stop_queue(dev);
++ return 0;
++}
++
++static int imq_open(struct net_device *dev)
++{
++ netif_start_queue(dev);
++ return 0;
++}
++
++static const struct net_device_ops imq_netdev_ops = {
++ .ndo_open = imq_open,
++ .ndo_stop = imq_close,
++ .ndo_start_xmit = imq_dev_xmit,
++ .ndo_get_stats = imq_get_stats,
++};
++
++static void imq_setup(struct net_device *dev)
++{
++ dev->netdev_ops = &imq_netdev_ops;
++ dev->type = ARPHRD_VOID;
++ dev->mtu = 16000;
++ dev->tx_queue_len = 11000;
++ dev->flags = IFF_NOARP;
++ dev->features = NETIF_F_SG | NETIF_F_FRAGLIST |
++ NETIF_F_GSO | NETIF_F_HW_CSUM |
++ NETIF_F_HIGHDMA;
++ dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
++}
++
++static int imq_validate(struct nlattr *tb[], struct nlattr *data[])
++{
++ int ret = 0;
++
++ if (tb[IFLA_ADDRESS]) {
++ if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) {
++ ret = -EINVAL;
++ goto end;
++ }
++ if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) {
++ ret = -EADDRNOTAVAIL;
++ goto end;
++ }
++ }
++ return 0;
++end:
++ printk(KERN_WARNING "IMQ: imq_validate failed (%d)\n", ret);
++ return ret;
++}
++
++static struct rtnl_link_ops imq_link_ops __read_mostly = {
++ .kind = "imq",
++ .priv_size = 0,
++ .setup = imq_setup,
++ .validate = imq_validate,
++};
++
++static int __init imq_init_hooks(void)
++{
++ int err;
++
++ nf_register_queue_imq_handler(&nfqh);
++
++ err = nf_register_hook(&imq_ingress_ipv4);
++ if (err)
++ goto err1;
++
++ err = nf_register_hook(&imq_egress_ipv4);
++ if (err)
++ goto err2;
++
++#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
++ err = nf_register_hook(&imq_ingress_ipv6);
++ if (err)
++ goto err3;
++
++ err = nf_register_hook(&imq_egress_ipv6);
++ if (err)
++ goto err4;
++#endif
++
++ return 0;
++
++#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
++err4:
++ nf_unregister_hook(&imq_ingress_ipv6);
++err3:
++ nf_unregister_hook(&imq_egress_ipv4);
++#endif
++err2:
++ nf_unregister_hook(&imq_ingress_ipv4);
++err1:
++ nf_unregister_queue_imq_handler();
++ return err;
++}
++
++static int __init imq_init_one(int index)
++{
++ struct net_device *dev;
++ int ret;
++
++ dev = alloc_netdev(0, "imq%d", imq_setup);
++ if (!dev)
++ return -ENOMEM;
++
++ ret = dev_alloc_name(dev, dev->name);
++ if (ret < 0)
++ goto fail;
++
++ dev->rtnl_link_ops = &imq_link_ops;
++ ret = register_netdevice(dev);
++ if (ret < 0)
++ goto fail;
++
++ return 0;
++fail:
++ free_netdev(dev);
++ return ret;
++}
++
++static int __init imq_init_devs(void)
++{
++ int err, i;
++
++ if (numdevs < 1 || numdevs > IMQ_MAX_DEVS) {
++ printk(KERN_ERR "IMQ: numdevs has to be betweed 1 and %u\n",
++ IMQ_MAX_DEVS);
++ return -EINVAL;
++ }
++
++ rtnl_lock();
++ err = __rtnl_link_register(&imq_link_ops);
++
++ for (i = 0; i < numdevs && !err; i++)
++ err = imq_init_one(i);
++
++ if (err) {
++ __rtnl_link_unregister(&imq_link_ops);
++ memset(imq_devs_cache, 0, sizeof(imq_devs_cache));
++ }
++ rtnl_unlock();
++
++ return err;
++}
++
++static int __init imq_init_module(void)
++{
++ int err;
++
++#if defined(CONFIG_IMQ_NUM_DEVS)
++ BUILD_BUG_ON(CONFIG_IMQ_NUM_DEVS > 16);
++ BUILD_BUG_ON(CONFIG_IMQ_NUM_DEVS < 2);
++ BUILD_BUG_ON(CONFIG_IMQ_NUM_DEVS - 1 > IMQ_F_IFMASK);
++#endif
++
++ err = imq_init_devs();
++ if (err) {
++ printk(KERN_ERR "IMQ: Error trying imq_init_devs(net)\n");
++ return err;
++ }
++
++ err = imq_init_hooks();
++ if (err) {
++ printk(KERN_ERR "IMQ: Error trying imq_init_hooks()\n");
++ rtnl_link_unregister(&imq_link_ops);
++ memset(imq_devs_cache, 0, sizeof(imq_devs_cache));
++ return err;
++ }
++
++ printk(KERN_INFO "IMQ driver loaded successfully.\n");
++
++#if defined(CONFIG_IMQ_BEHAVIOR_BA) || defined(CONFIG_IMQ_BEHAVIOR_BB)
++ printk(KERN_INFO "\tHooking IMQ before NAT on PREROUTING.\n");
++#else
++ printk(KERN_INFO "\tHooking IMQ after NAT on PREROUTING.\n");
++#endif
++#if defined(CONFIG_IMQ_BEHAVIOR_AB) || defined(CONFIG_IMQ_BEHAVIOR_BB)
++ printk(KERN_INFO "\tHooking IMQ before NAT on POSTROUTING.\n");
++#else
++ printk(KERN_INFO "\tHooking IMQ after NAT on POSTROUTING.\n");
++#endif
++
++ return 0;
++}
++
++static void __exit imq_unhook(void)
++{
++#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
++ nf_unregister_hook(&imq_ingress_ipv6);
++ nf_unregister_hook(&imq_egress_ipv6);
++#endif
++ nf_unregister_hook(&imq_ingress_ipv4);
++ nf_unregister_hook(&imq_egress_ipv4);
++
++ nf_unregister_queue_imq_handler();
++}
++
++static void __exit imq_cleanup_devs(void)
++{
++ rtnl_link_unregister(&imq_link_ops);
++ memset(imq_devs_cache, 0, sizeof(imq_devs_cache));
++}
++
++static void __exit imq_exit_module(void)
++{
++ imq_unhook();
++ imq_cleanup_devs();
++ printk(KERN_INFO "IMQ driver unloaded successfully.\n");
++}
++
++module_init(imq_init_module);
++module_exit(imq_exit_module);
++
++module_param(numdevs, int, 0);
++MODULE_PARM_DESC(numdevs, "number of IMQ devices (how many imq* devices will "
++ "be created)");
++MODULE_AUTHOR("http://www.linuximq.net");
++MODULE_DESCRIPTION("Pseudo-driver for the intermediate queue device. See "
++ "http://www.linuximq.net/ for more information.");
++MODULE_LICENSE("GPL");
++MODULE_ALIAS_RTNL_LINK("imq");
++
+--- a/drivers/net/Kconfig
++++ b/drivers/net/Kconfig
+@@ -121,6 +121,129 @@ config EQUALIZER
+ To compile this driver as a module, choose M here: the module
+ will be called eql. If unsure, say N.
+
++config IMQ
++ tristate "IMQ (intermediate queueing device) support"
++ depends on NETDEVICES && NETFILTER
++ ---help---
++ The IMQ device(s) is used as placeholder for QoS queueing
++ disciplines. Every packet entering/leaving the IP stack can be
++ directed through the IMQ device where it's enqueued/dequeued to the
++ attached qdisc. This allows you to treat network devices as classes
++ and distribute bandwidth among them. Iptables is used to specify
++ through which IMQ device, if any, packets travel.
++
++ More information at: http://www.linuximq.net/
++
++ To compile this driver as a module, choose M here: the module
++ will be called imq. If unsure, say N.
++
++choice
++ prompt "IMQ behavior (PRE/POSTROUTING)"
++ depends on IMQ
++ default IMQ_BEHAVIOR_AB
++ help
++
++ This settings defines how IMQ behaves in respect to its
++ hooking in PREROUTING and POSTROUTING.
++
++ IMQ can work in any of the following ways:
++
++ PREROUTING | POSTROUTING
++ -----------------|-------------------
++ #1 After NAT | After NAT
++ #2 After NAT | Before NAT
++ #3 Before NAT | After NAT
++ #4 Before NAT | Before NAT
++
++ The default behavior is to hook before NAT on PREROUTING
++ and after NAT on POSTROUTING (#3).
++
++ This settings are specially usefull when trying to use IMQ
++ to shape NATed clients.
++
++ More information can be found at: www.linuximq.net
++
++ If not sure leave the default settings alone.
++
++config IMQ_BEHAVIOR_AA
++ bool "IMQ AA"
++ help
++ This settings defines how IMQ behaves in respect to its
++ hooking in PREROUTING and POSTROUTING.
++
++ Choosing this option will make IMQ hook like this:
++
++ PREROUTING: After NAT
++ POSTROUTING: After NAT
++
++ More information can be found at: www.linuximq.net
++
++ If not sure leave the default settings alone.
++
++config IMQ_BEHAVIOR_AB
++ bool "IMQ AB"
++ help
++ This settings defines how IMQ behaves in respect to its
++ hooking in PREROUTING and POSTROUTING.
++
++ Choosing this option will make IMQ hook like this:
++
++ PREROUTING: After NAT
++ POSTROUTING: Before NAT
++
++ More information can be found at: www.linuximq.net
++
++ If not sure leave the default settings alone.
++
++config IMQ_BEHAVIOR_BA
++ bool "IMQ BA"
++ help
++ This settings defines how IMQ behaves in respect to its
++ hooking in PREROUTING and POSTROUTING.
++
++ Choosing this option will make IMQ hook like this:
++
++ PREROUTING: Before NAT
++ POSTROUTING: After NAT
++
++ More information can be found at: www.linuximq.net
++
++ If not sure leave the default settings alone.
++
++config IMQ_BEHAVIOR_BB
++ bool "IMQ BB"
++ help
++ This settings defines how IMQ behaves in respect to its
++ hooking in PREROUTING and POSTROUTING.
++
++ Choosing this option will make IMQ hook like this:
++
++ PREROUTING: Before NAT
++ POSTROUTING: Before NAT
++
++ More information can be found at: www.linuximq.net
++
++ If not sure leave the default settings alone.
++
++endchoice
++
++config IMQ_NUM_DEVS
++
++ int "Number of IMQ devices"
++ range 2 16
++ depends on IMQ
++ default "16"
++ help
++
++ This settings defines how many IMQ devices will be
++ created.
++
++ The default value is 16.
++
++ More information can be found at: www.linuximq.net
++
++ If not sure leave the default settings alone.
++
+ config TUN
+ tristate "Universal TUN/TAP device driver support"
+ select CRC32
+--- a/drivers/net/Makefile
++++ b/drivers/net/Makefile
+@@ -169,6 +169,7 @@ obj-$(CONFIG_SLHC) += slhc.o
+ obj-$(CONFIG_XEN_NETDEV_FRONTEND) += xen-netfront.o
+
+ obj-$(CONFIG_DUMMY) += dummy.o
++obj-$(CONFIG_IMQ) += imq.o
+ obj-$(CONFIG_IFB) += ifb.o
+ obj-$(CONFIG_MACVLAN) += macvlan.o
+ obj-$(CONFIG_MACVTAP) += macvtap.o
+--- /dev/null
++++ b/include/linux/imq.h
+@@ -0,0 +1,13 @@
++#ifndef _IMQ_H
++#define _IMQ_H
++
++/* IFMASK (16 device indexes, 0 to 15) and flag(s) fit in 5 bits */
++#define IMQ_F_BITS 5
++
++#define IMQ_F_IFMASK 0x0f
++#define IMQ_F_ENQUEUE 0x10
++
++#define IMQ_MAX_DEVS (IMQ_F_IFMASK + 1)
++
++#endif /* _IMQ_H */
++
+--- a/include/linux/netdevice.h
++++ b/include/linux/netdevice.h
+@@ -1281,6 +1281,7 @@ extern int dev_alloc_name(struct net_de
+ extern int dev_open(struct net_device *dev);
+ extern int dev_close(struct net_device *dev);
+ extern void dev_disable_lro(struct net_device *dev);
++extern struct netdev_queue *dev_pick_tx(struct net_device *dev, struct sk_buff *skb);
+ extern int dev_queue_xmit(struct sk_buff *skb);
+ extern int register_netdevice(struct net_device *dev);
+ extern void unregister_netdevice_queue(struct net_device *dev,
+--- /dev/null
++++ b/include/linux/netfilter/xt_IMQ.h
+@@ -0,0 +1,9 @@
++#ifndef _XT_IMQ_H
++#define _XT_IMQ_H
++
++struct xt_imq_info {
++ unsigned int todev; /* target imq device */
++};
++
++#endif /* _XT_IMQ_H */
++
+--- /dev/null
++++ b/include/linux/netfilter_ipv4/ipt_IMQ.h
+@@ -0,0 +1,10 @@
++#ifndef _IPT_IMQ_H
++#define _IPT_IMQ_H
++
++/* Backwards compatibility for old userspace */
++#include <linux/netfilter/xt_IMQ.h>
++
++#define ipt_imq_info xt_imq_info
++
++#endif /* _IPT_IMQ_H */
++
+--- /dev/null
++++ b/include/linux/netfilter_ipv6/ip6t_IMQ.h
+@@ -0,0 +1,10 @@
++#ifndef _IP6T_IMQ_H
++#define _IP6T_IMQ_H
++
++/* Backwards compatibility for old userspace */
++#include <linux/netfilter/xt_IMQ.h>
++
++#define ip6t_imq_info xt_imq_info
++
++#endif /* _IP6T_IMQ_H */
++
+--- a/include/linux/skbuff.h
++++ b/include/linux/skbuff.h
+@@ -29,6 +29,9 @@
+ #include <linux/rcupdate.h>
+ #include <linux/dmaengine.h>
+ #include <linux/hrtimer.h>
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++#include <linux/imq.h>
++#endif
+
+ /* Don't change this without changing skb_csum_unnecessary! */
+ #define CHECKSUM_NONE 0
+@@ -329,6 +332,9 @@ struct sk_buff {
+ * first. This is owned by whoever has the skb queued ATM.
+ */
+ char cb[48] __aligned(8);
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ void *cb_next;
++#endif
+
+ unsigned long _skb_refdst;
+ #ifdef CONFIG_XFRM
+@@ -365,6 +371,9 @@ struct sk_buff {
+ struct nf_conntrack *nfct;
+ struct sk_buff *nfct_reasm;
+ #endif
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ struct nf_queue_entry *nf_queue_entry;
++#endif
+ #ifdef CONFIG_BRIDGE_NETFILTER
+ struct nf_bridge_info *nf_bridge;
+ #endif
+@@ -391,6 +400,10 @@ struct sk_buff {
+
+ /* 0/14 bit hole */
+
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ __u8 imq_flags:IMQ_F_BITS;
++#endif
++
+ #ifdef CONFIG_NET_DMA
+ dma_cookie_t dma_cookie;
+ #endif
+@@ -489,6 +502,12 @@ static inline struct rtable *skb_rtable(
+ return (struct rtable *)skb_dst(skb);
+ }
+
++
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++extern int skb_save_cb(struct sk_buff *skb);
++extern int skb_restore_cb(struct sk_buff *skb);
++#endif
++
+ extern void kfree_skb(struct sk_buff *skb);
+ extern void consume_skb(struct sk_buff *skb);
+ extern void __kfree_skb(struct sk_buff *skb);
+@@ -2036,6 +2055,10 @@ static inline void __nf_copy(struct sk_b
+ dst->nfct_reasm = src->nfct_reasm;
+ nf_conntrack_get_reasm(src->nfct_reasm);
+ #endif
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ dst->imq_flags = src->imq_flags;
++ dst->nf_queue_entry = src->nf_queue_entry;
++#endif
+ #ifdef CONFIG_BRIDGE_NETFILTER
+ dst->nf_bridge = src->nf_bridge;
+ nf_bridge_get(src->nf_bridge);
+--- a/include/net/netfilter/nf_queue.h
++++ b/include/net/netfilter/nf_queue.h
+@@ -13,6 +13,12 @@ struct nf_queue_entry {
+ struct net_device *indev;
+ struct net_device *outdev;
+ int (*okfn)(struct sk_buff *);
++
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ int (*next_outfn)(struct nf_queue_entry *entry,
++ unsigned int queuenum);
++ unsigned int next_queuenum;
++#endif
+ };
+
+ #define nf_queue_entry_reroute(x) ((void *)x + sizeof(struct nf_queue_entry))
+@@ -30,5 +36,11 @@ extern int nf_unregister_queue_handler(u
+ const struct nf_queue_handler *qh);
+ extern void nf_unregister_queue_handlers(const struct nf_queue_handler *qh);
+ extern void nf_reinject(struct nf_queue_entry *entry, unsigned int verdict);
++extern void nf_queue_entry_release_refs(struct nf_queue_entry *entry);
++
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++extern void nf_register_queue_imq_handler(const struct nf_queue_handler *qh);
++extern void nf_unregister_queue_imq_handler(void);
++#endif
+
+ #endif /* _NF_QUEUE_H */
+--- a/net/core/dev.c
++++ b/net/core/dev.c
+@@ -98,6 +98,9 @@
+ #include <net/net_namespace.h>
+ #include <net/sock.h>
+ #include <linux/rtnetlink.h>
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++#include <linux/imq.h>
++#endif
+ #include <linux/proc_fs.h>
+ #include <linux/seq_file.h>
+ #include <linux/stat.h>
+@@ -1931,7 +1934,11 @@ int dev_hard_start_xmit(struct sk_buff *
+ int rc = NETDEV_TX_OK;
+
+ if (likely(!skb->next)) {
+- if (!list_empty(&ptype_all))
++ if (!list_empty(&ptype_all)
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ && !(skb->imq_flags & IMQ_F_ENQUEUE)
++#endif
++ )
+ dev_queue_xmit_nit(skb, dev);
+
+ /*
+@@ -2027,8 +2034,7 @@ static inline u16 dev_cap_txqueue(struct
+ return queue_index;
+ }
+
+-static struct netdev_queue *dev_pick_tx(struct net_device *dev,
+- struct sk_buff *skb)
++struct netdev_queue *dev_pick_tx(struct net_device *dev, struct sk_buff *skb)
+ {
+ int queue_index;
+ struct sock *sk = skb->sk;
+@@ -2057,6 +2063,7 @@ static struct netdev_queue *dev_pick_tx(
+ skb_set_queue_mapping(skb, queue_index);
+ return netdev_get_tx_queue(dev, queue_index);
+ }
++EXPORT_SYMBOL(dev_pick_tx);
+
+ static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
+ struct net_device *dev,
+--- a/net/core/skbuff.c
++++ b/net/core/skbuff.c
+@@ -72,6 +72,9 @@
+
+ static struct kmem_cache *skbuff_head_cache __read_mostly;
+ static struct kmem_cache *skbuff_fclone_cache __read_mostly;
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++static struct kmem_cache *skbuff_cb_store_cache __read_mostly;
++#endif
+
+ static void sock_pipe_buf_release(struct pipe_inode_info *pipe,
+ struct pipe_buffer *buf)
+@@ -91,6 +94,83 @@ static int sock_pipe_buf_steal(struct pi
+ return 1;
+ }
+
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++/* Control buffer save/restore for IMQ devices */
++struct skb_cb_table {
++ void *cb_next;
++ atomic_t refcnt;
++ char cb[48];
++};
++
++static DEFINE_SPINLOCK(skb_cb_store_lock);
++
++int skb_save_cb(struct sk_buff *skb)
++{
++ struct skb_cb_table *next;
++
++ next = kmem_cache_alloc(skbuff_cb_store_cache, GFP_ATOMIC);
++ if (!next)
++ return -ENOMEM;
++
++ BUILD_BUG_ON(sizeof(skb->cb) != sizeof(next->cb));
++
++ memcpy(next->cb, skb->cb, sizeof(skb->cb));
++ next->cb_next = skb->cb_next;
++
++ atomic_set(&next->refcnt, 1);
++
++ skb->cb_next = next;
++ return 0;
++}
++EXPORT_SYMBOL(skb_save_cb);
++
++int skb_restore_cb(struct sk_buff *skb)
++{
++ struct skb_cb_table *next;
++
++ if (!skb->cb_next)
++ return 0;
++
++ next = skb->cb_next;
++
++ BUILD_BUG_ON(sizeof(skb->cb) != sizeof(next->cb));
++
++ memcpy(skb->cb, next->cb, sizeof(skb->cb));
++ skb->cb_next = next->cb_next;
++
++ spin_lock(&skb_cb_store_lock);
++
++ if (atomic_dec_and_test(&next->refcnt)) {
++ kmem_cache_free(skbuff_cb_store_cache, next);
++ }
++
++ spin_unlock(&skb_cb_store_lock);
++
++ return 0;
++}
++EXPORT_SYMBOL(skb_restore_cb);
++
++static void skb_copy_stored_cb(struct sk_buff *new, const struct sk_buff *__old)
++{
++ struct skb_cb_table *next;
++ struct sk_buff *old;
++
++ if (!__old->cb_next) {
++ new->cb_next = NULL;
++ return;
++ }
++
++ spin_lock(&skb_cb_store_lock);
++
++ old = (struct sk_buff *)__old;
++
++ next = old->cb_next;
++ atomic_inc(&next->refcnt);
++ new->cb_next = next;
++
++ spin_unlock(&skb_cb_store_lock);
++}
++#endif
+
+ /* Pipe buffer operations for a socket. */
+ static const struct pipe_buf_operations sock_pipe_buf_ops = {
+@@ -391,6 +471,26 @@ static void skb_release_head_state(struc
+ WARN_ON(in_irq());
+ skb->destructor(skb);
+ }
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ /* This should not happen. When it does, avoid memleak by restoring
++ the chain of cb-backups. */
++ while(skb->cb_next != NULL) {
++ if (net_ratelimit())
++ printk(KERN_WARNING "IMQ: kfree_skb: skb->cb_next: "
++ "%08x\n", (unsigned int)skb->cb_next);
++
++ skb_restore_cb(skb);
++ }
++ /* This should not happen either, nf_queue_entry is nullified in
++ * imq_dev_xmit(). If we have non-NULL nf_queue_entry then we are
++ * leaking entry pointers, maybe memory. We don't know if this is
++ * pointer to already freed memory, or should this be freed.
++ * If this happens we need to add refcounting, etc for nf_queue_entry.
++ */
++ if (skb->nf_queue_entry && net_ratelimit())
++ printk(KERN_WARNING
++ "IMQ: kfree_skb: skb->nf_queue_entry != NULL");
++#endif
+ #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
+ nf_conntrack_put(skb->nfct);
+ nf_conntrack_put_reasm(skb->nfct_reasm);
+@@ -526,6 +626,9 @@ static void __copy_skb_header(struct sk_
+ new->sp = secpath_get(old->sp);
+ #endif
+ memcpy(new->cb, old->cb, sizeof(old->cb));
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ skb_copy_stored_cb(new, old);
++#endif
+ new->csum = old->csum;
+ new->local_df = old->local_df;
+ new->pkt_type = old->pkt_type;
+@@ -2780,6 +2883,13 @@ void __init skb_init(void)
+ 0,
+ SLAB_HWCACHE_ALIGN|SLAB_PANIC,
+ NULL);
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ skbuff_cb_store_cache = kmem_cache_create("skbuff_cb_store_cache",
++ sizeof(struct skb_cb_table),
++ 0,
++ SLAB_HWCACHE_ALIGN|SLAB_PANIC,
++ NULL);
++#endif
+ }
+
+ /**
+--- a/net/netfilter/Kconfig
++++ b/net/netfilter/Kconfig
+@@ -448,6 +448,18 @@ config NETFILTER_XT_TARGET_LED
+ For more information on the LEDs available on your system, see
+ Documentation/leds-class.txt
+
++config NETFILTER_XT_TARGET_IMQ
++ tristate '"IMQ" target support'
++ depends on NETFILTER_XTABLES
++ depends on IP_NF_MANGLE || IP6_NF_MANGLE
++ select IMQ
++ default m if NETFILTER_ADVANCED=n
++ help
++ This option adds a `IMQ' target which is used to specify if and
++ to which imq device packets should get enqueued/dequeued.
++
++ To compile it as a module, choose M here. If unsure, say N.
++
+ config NETFILTER_XT_TARGET_MARK
+ tristate '"MARK" target support'
+ depends on NETFILTER_ADVANCED
+--- a/net/netfilter/Makefile
++++ b/net/netfilter/Makefile
+@@ -50,6 +50,7 @@ obj-$(CONFIG_NETFILTER_XT_TARGET_CONNSEC
+ obj-$(CONFIG_NETFILTER_XT_TARGET_CT) += xt_CT.o
+ obj-$(CONFIG_NETFILTER_XT_TARGET_DSCP) += xt_DSCP.o
+ obj-$(CONFIG_NETFILTER_XT_TARGET_HL) += xt_HL.o
++obj-$(CONFIG_NETFILTER_XT_TARGET_IMQ) += xt_IMQ.o
+ obj-$(CONFIG_NETFILTER_XT_TARGET_LED) += xt_LED.o
+ obj-$(CONFIG_NETFILTER_XT_TARGET_NFLOG) += xt_NFLOG.o
+ obj-$(CONFIG_NETFILTER_XT_TARGET_NFQUEUE) += xt_NFQUEUE.o
+--- a/net/netfilter/nf_queue.c
++++ b/net/netfilter/nf_queue.c
+@@ -22,6 +22,26 @@ static const struct nf_queue_handler *qu
+
+ static DEFINE_MUTEX(queue_handler_mutex);
+
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++static const struct nf_queue_handler *queue_imq_handler;
++
++void nf_register_queue_imq_handler(const struct nf_queue_handler *qh)
++{
++ mutex_lock(&queue_handler_mutex);
++ rcu_assign_pointer(queue_imq_handler, qh);
++ mutex_unlock(&queue_handler_mutex);
++}
++EXPORT_SYMBOL(nf_register_queue_imq_handler);
++
++void nf_unregister_queue_imq_handler(void)
++{
++ mutex_lock(&queue_handler_mutex);
++ rcu_assign_pointer(queue_imq_handler, NULL);
++ mutex_unlock(&queue_handler_mutex);
++}
++EXPORT_SYMBOL(nf_unregister_queue_imq_handler);
++#endif
++
+ /* return EBUSY when somebody else is registered, return EEXIST if the
+ * same handler is registered, return 0 in case of success. */
+ int nf_register_queue_handler(u_int8_t pf, const struct nf_queue_handler *qh)
+@@ -82,7 +102,7 @@ void nf_unregister_queue_handlers(const
+ }
+ EXPORT_SYMBOL_GPL(nf_unregister_queue_handlers);
+
+-static void nf_queue_entry_release_refs(struct nf_queue_entry *entry)
++void nf_queue_entry_release_refs(struct nf_queue_entry *entry)
+ {
+ /* Release those devices we held, or Alexey will kill me. */
+ if (entry->indev)
+@@ -102,6 +122,7 @@ static void nf_queue_entry_release_refs(
+ /* Drop reference to owner of hook which queued us. */
+ module_put(entry->elem->owner);
+ }
++EXPORT_SYMBOL_GPL(nf_queue_entry_release_refs);
+
+ /*
+ * Any packet that leaves via this function must come back
+@@ -123,12 +144,26 @@ static int __nf_queue(struct sk_buff *sk
+ #endif
+ const struct nf_afinfo *afinfo;
+ const struct nf_queue_handler *qh;
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ const struct nf_queue_handler *qih = NULL;
++#endif
+
+ /* QUEUE == DROP if noone is waiting, to be safe. */
+ rcu_read_lock();
+
+ qh = rcu_dereference(queue_handler[pf]);
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
++ if (pf == PF_INET || pf == PF_INET6)
++#else
++ if (pf == PF_INET)
++#endif
++ qih = rcu_dereference(queue_imq_handler);
++
++ if (!qh && !qih)
++#else /* !IMQ */
+ if (!qh)
++#endif
+ goto err_unlock;
+
+ afinfo = nf_get_afinfo(pf);
+@@ -147,6 +182,10 @@ static int __nf_queue(struct sk_buff *sk
+ .indev = indev,
+ .outdev = outdev,
+ .okfn = okfn,
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ .next_outfn = qh ? qh->outfn : NULL,
++ .next_queuenum = queuenum,
++#endif
+ };
+
+ /* If it's going away, ignore hook. */
+@@ -173,8 +212,19 @@ static int __nf_queue(struct sk_buff *sk
+ #endif
+ skb_dst_force(skb);
+ afinfo->saveroute(skb, entry);
++
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ if (qih) {
++ status = qih->outfn(entry, queuenum);
++ goto imq_skip_queue;
++ }
++#endif
++
+ status = qh->outfn(entry, queuenum);
+
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++imq_skip_queue:
++#endif
+ rcu_read_unlock();
+
+ if (status < 0) {
+--- /dev/null
++++ b/net/netfilter/xt_IMQ.c
+@@ -0,0 +1,73 @@
++/*
++ * This target marks packets to be enqueued to an imq device
++ */
++#include <linux/module.h>
++#include <linux/skbuff.h>
++#include <linux/netfilter/x_tables.h>
++#include <linux/netfilter/xt_IMQ.h>
++#include <linux/imq.h>
++
++static unsigned int imq_target(struct sk_buff *pskb,
++ const struct xt_action_param *par)
++{
++ const struct xt_imq_info *mr = par->targinfo;
++
++ pskb->imq_flags = (mr->todev & IMQ_F_IFMASK) | IMQ_F_ENQUEUE;
++
++ return XT_CONTINUE;
++}
++
++static int imq_checkentry(const struct xt_tgchk_param *par)
++{
++ struct xt_imq_info *mr = par->targinfo;
++
++ if (mr->todev > IMQ_MAX_DEVS - 1) {
++ printk(KERN_WARNING
++ "IMQ: invalid device specified, highest is %u\n",
++ IMQ_MAX_DEVS - 1);
++ return -EINVAL;
++ }
++
++ return 0;
++}
++
++static struct xt_target xt_imq_reg[] __read_mostly = {
++ {
++ .name = "IMQ",
++ .family = AF_INET,
++ .checkentry = imq_checkentry,
++ .target = imq_target,
++ .targetsize = sizeof(struct xt_imq_info),
++ .table = "mangle",
++ .me = THIS_MODULE
++ },
++ {
++ .name = "IMQ",
++ .family = AF_INET6,
++ .checkentry = imq_checkentry,
++ .target = imq_target,
++ .targetsize = sizeof(struct xt_imq_info),
++ .table = "mangle",
++ .me = THIS_MODULE
++ },
++};
++
++static int __init imq_init(void)
++{
++ return xt_register_targets(xt_imq_reg, ARRAY_SIZE(xt_imq_reg));
++}
++
++static void __exit imq_fini(void)
++{
++ xt_unregister_targets(xt_imq_reg, ARRAY_SIZE(xt_imq_reg));
++}
++
++module_init(imq_init);
++module_exit(imq_fini);
++
++MODULE_AUTHOR("http://www.linuximq.net");
++MODULE_DESCRIPTION("Pseudo-driver for the intermediate queue device. See http://www.linuximq.net/ for more information.");
++MODULE_LICENSE("GPL");
++MODULE_ALIAS("ipt_IMQ");
++MODULE_ALIAS("ip6t_IMQ");
++
--- /dev/null
+--- /dev/null
++++ b/drivers/net/imq.c
+@@ -0,0 +1,638 @@
++/*
++ * Pseudo-driver for the intermediate queue device.
++ *
++ * 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.
++ *
++ * Authors: Patrick McHardy, <kaber@trash.net>
++ *
++ * The first version was written by Martin Devera, <devik@cdi.cz>
++ *
++ * Credits: Jan Rafaj <imq2t@cedric.vabo.cz>
++ * - Update patch to 2.4.21
++ * Sebastian Strollo <sstrollo@nortelnetworks.com>
++ * - Fix "Dead-loop on netdevice imq"-issue
++ * Marcel Sebek <sebek64@post.cz>
++ * - Update to 2.6.2-rc1
++ *
++ * After some time of inactivity there is a group taking care
++ * of IMQ again: http://www.linuximq.net
++ *
++ *
++ * 2004/06/30 - New version of IMQ patch to kernels <=2.6.7
++ * including the following changes:
++ *
++ * - Correction of ipv6 support "+"s issue (Hasso Tepper)
++ * - Correction of imq_init_devs() issue that resulted in
++ * kernel OOPS unloading IMQ as module (Norbert Buchmuller)
++ * - Addition of functionality to choose number of IMQ devices
++ * during kernel config (Andre Correa)
++ * - Addition of functionality to choose how IMQ hooks on
++ * PRE and POSTROUTING (after or before NAT) (Andre Correa)
++ * - Cosmetic corrections (Norbert Buchmuller) (Andre Correa)
++ *
++ *
++ * 2005/12/16 - IMQ versions between 2.6.7 and 2.6.13 were
++ * released with almost no problems. 2.6.14-x was released
++ * with some important changes: nfcache was removed; After
++ * some weeks of trouble we figured out that some IMQ fields
++ * in skb were missing in skbuff.c - skb_clone and copy_skb_header.
++ * These functions are correctly patched by this new patch version.
++ *
++ * Thanks for all who helped to figure out all the problems with
++ * 2.6.14.x: Patrick McHardy, Rune Kock, VeNoMouS, Max CtRiX,
++ * Kevin Shanahan, Richard Lucassen, Valery Dachev (hopefully
++ * I didn't forget anybody). I apologize again for my lack of time.
++ *
++ *
++ * 2008/06/17 - 2.6.25 - Changed imq.c to use qdisc_run() instead
++ * of qdisc_restart() and moved qdisc_run() to tasklet to avoid
++ * recursive locking. New initialization routines to fix 'rmmod' not
++ * working anymore. Used code from ifb.c. (Jussi Kivilinna)
++ *
++ * 2008/08/06 - 2.6.26 - (JK)
++ * - Replaced tasklet with 'netif_schedule()'.
++ * - Cleaned up and added comments for imq_nf_queue().
++ *
++ * 2009/04/12
++ * - Add skb_save_cb/skb_restore_cb helper functions for backuping
++ * control buffer. This is needed because qdisc-layer on kernels
++ * 2.6.27 and newer overwrite control buffer. (Jussi Kivilinna)
++ * - Add better locking for IMQ device. Hopefully this will solve
++ * SMP issues. (Jussi Kivilinna)
++ * - Port to 2.6.27
++ * - Port to 2.6.28
++ * - Port to 2.6.29 + fix rmmod not working
++ *
++ * 2009/04/20 - (Jussi Kivilinna)
++ * - Use netdevice feature flags to avoid extra packet handling
++ * by core networking layer and possibly increase performance.
++ *
++ * 2009/09/26 - (Jussi Kivilinna)
++ * - Add imq_nf_reinject_lockless to fix deadlock with
++ * imq_nf_queue/imq_nf_reinject.
++ *
++ * 2009/12/08 - (Jussi Kivilinna)
++ * - Port to 2.6.32
++ * - Add check for skb->nf_queue_entry==NULL in imq_dev_xmit()
++ * - Also add better error checking for skb->nf_queue_entry usage
++ *
++ * 2010/02/25 - (Jussi Kivilinna)
++ * - Port to 2.6.33
++ *
++ * 2010/08/12 - (Jussi Kivilinna)
++ * - Port to 2.6.35
++ *
++ * Also, many thanks to pablo Sebastian Greco for making the initial
++ * patch and to those who helped the testing.
++ *
++ * More info at: http://www.linuximq.net/ (Andre Correa)
++ */
++
++#include <linux/module.h>
++#include <linux/kernel.h>
++#include <linux/moduleparam.h>
++#include <linux/list.h>
++#include <linux/skbuff.h>
++#include <linux/netdevice.h>
++#include <linux/etherdevice.h>
++#include <linux/rtnetlink.h>
++#include <linux/if_arp.h>
++#include <linux/netfilter.h>
++#include <linux/netfilter_ipv4.h>
++#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
++ #include <linux/netfilter_ipv6.h>
++#endif
++#include <linux/imq.h>
++#include <net/pkt_sched.h>
++#include <net/netfilter/nf_queue.h>
++
++static nf_hookfn imq_nf_hook;
++
++static struct nf_hook_ops imq_ingress_ipv4 = {
++ .hook = imq_nf_hook,
++ .owner = THIS_MODULE,
++ .pf = PF_INET,
++ .hooknum = NF_INET_PRE_ROUTING,
++#if defined(CONFIG_IMQ_BEHAVIOR_BA) || defined(CONFIG_IMQ_BEHAVIOR_BB)
++ .priority = NF_IP_PRI_MANGLE + 1
++#else
++ .priority = NF_IP_PRI_NAT_DST + 1
++#endif
++};
++
++static struct nf_hook_ops imq_egress_ipv4 = {
++ .hook = imq_nf_hook,
++ .owner = THIS_MODULE,
++ .pf = PF_INET,
++ .hooknum = NF_INET_POST_ROUTING,
++#if defined(CONFIG_IMQ_BEHAVIOR_AA) || defined(CONFIG_IMQ_BEHAVIOR_BA)
++ .priority = NF_IP_PRI_LAST
++#else
++ .priority = NF_IP_PRI_NAT_SRC - 1
++#endif
++};
++
++#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
++static struct nf_hook_ops imq_ingress_ipv6 = {
++ .hook = imq_nf_hook,
++ .owner = THIS_MODULE,
++ .pf = PF_INET6,
++ .hooknum = NF_INET_PRE_ROUTING,
++#if defined(CONFIG_IMQ_BEHAVIOR_BA) || defined(CONFIG_IMQ_BEHAVIOR_BB)
++ .priority = NF_IP6_PRI_MANGLE + 1
++#else
++ .priority = NF_IP6_PRI_NAT_DST + 1
++#endif
++};
++
++static struct nf_hook_ops imq_egress_ipv6 = {
++ .hook = imq_nf_hook,
++ .owner = THIS_MODULE,
++ .pf = PF_INET6,
++ .hooknum = NF_INET_POST_ROUTING,
++#if defined(CONFIG_IMQ_BEHAVIOR_AA) || defined(CONFIG_IMQ_BEHAVIOR_BA)
++ .priority = NF_IP6_PRI_LAST
++#else
++ .priority = NF_IP6_PRI_NAT_SRC - 1
++#endif
++};
++#endif
++
++#if defined(CONFIG_IMQ_NUM_DEVS)
++static unsigned int numdevs = CONFIG_IMQ_NUM_DEVS;
++#else
++static unsigned int numdevs = IMQ_MAX_DEVS;
++#endif
++
++static DEFINE_SPINLOCK(imq_nf_queue_lock);
++
++static struct net_device *imq_devs_cache[IMQ_MAX_DEVS];
++
++
++static struct net_device_stats *imq_get_stats(struct net_device *dev)
++{
++ return &dev->stats;
++}
++
++/* called for packets kfree'd in qdiscs at places other than enqueue */
++static void imq_skb_destructor(struct sk_buff *skb)
++{
++ struct nf_queue_entry *entry = skb->nf_queue_entry;
++
++ skb->nf_queue_entry = NULL;
++
++ if (entry) {
++ nf_queue_entry_release_refs(entry);
++ kfree(entry);
++ }
++
++ skb_restore_cb(skb); /* kfree backup */
++}
++
++/* locking not needed when called from imq_nf_queue */
++static void imq_nf_reinject_lockless(struct nf_queue_entry *entry,
++ unsigned int verdict)
++{
++ int status;
++
++ if (!entry->next_outfn) {
++ nf_reinject(entry, verdict);
++ return;
++ }
++
++ status = entry->next_outfn(entry, entry->next_queuenum);
++ if (status < 0) {
++ nf_queue_entry_release_refs(entry);
++ kfree_skb(entry->skb);
++ kfree(entry);
++ }
++}
++
++static void imq_nf_reinject(struct nf_queue_entry *entry, unsigned int verdict)
++{
++ int status;
++
++ if (!entry->next_outfn) {
++ spin_lock_bh(&imq_nf_queue_lock);
++ nf_reinject(entry, verdict);
++ spin_unlock_bh(&imq_nf_queue_lock);
++ return;
++ }
++
++ rcu_read_lock();
++ local_bh_disable();
++ status = entry->next_outfn(entry, entry->next_queuenum);
++ local_bh_enable();
++ if (status < 0) {
++ nf_queue_entry_release_refs(entry);
++ kfree_skb(entry->skb);
++ kfree(entry);
++ }
++
++ rcu_read_unlock();
++}
++
++static netdev_tx_t imq_dev_xmit(struct sk_buff *skb, struct net_device *dev)
++{
++ struct nf_queue_entry *entry = skb->nf_queue_entry;
++
++ skb->nf_queue_entry = NULL;
++ dev->trans_start = jiffies;
++
++ dev->stats.tx_bytes += skb->len;
++ dev->stats.tx_packets++;
++
++ if (entry == NULL) {
++ /* We don't know what is going on here.. packet is queued for
++ * imq device, but (probably) not by us.
++ *
++ * If this packet was not send here by imq_nf_queue(), then
++ * skb_save_cb() was not used and skb_free() should not show:
++ * WARNING: IMQ: kfree_skb: skb->cb_next:..
++ * and/or
++ * WARNING: IMQ: kfree_skb: skb->nf_queue_entry...
++ *
++ * However if this message is shown, then IMQ is somehow broken
++ * and you should report this to linuximq.net.
++ */
++
++ /* imq_dev_xmit is black hole that eats all packets, report that
++ * we eat this packet happily and increase dropped counters.
++ */
++
++ dev->stats.tx_dropped++;
++ dev_kfree_skb(skb);
++
++ return NETDEV_TX_OK;
++ }
++
++ skb_restore_cb(skb); /* restore skb->cb */
++
++ skb->imq_flags = 0;
++ skb->destructor = NULL;
++
++ imq_nf_reinject(entry, NF_ACCEPT);
++
++ return NETDEV_TX_OK;
++}
++
++static int imq_nf_queue(struct nf_queue_entry *entry, unsigned queue_num)
++{
++ struct net_device *dev;
++ struct sk_buff *skb_orig, *skb, *skb_shared;
++ struct Qdisc *q;
++ struct netdev_queue *txq;
++ int users, index;
++ int retval = -EINVAL;
++
++ index = entry->skb->imq_flags & IMQ_F_IFMASK;
++ if (unlikely(index > numdevs - 1)) {
++ if (net_ratelimit())
++ printk(KERN_WARNING
++ "IMQ: invalid device specified, highest is %u\n",
++ numdevs - 1);
++ retval = -EINVAL;
++ goto out;
++ }
++
++ /* check for imq device by index from cache */
++ dev = imq_devs_cache[index];
++ if (unlikely(!dev)) {
++ char buf[8];
++
++ /* get device by name and cache result */
++ snprintf(buf, sizeof(buf), "imq%d", index);
++ dev = dev_get_by_name(&init_net, buf);
++ if (!dev) {
++ /* not found ?!*/
++ BUG();
++ retval = -ENODEV;
++ goto out;
++ }
++
++ imq_devs_cache[index] = dev;
++ dev_put(dev);
++ }
++
++ if (unlikely(!(dev->flags & IFF_UP))) {
++ entry->skb->imq_flags = 0;
++ imq_nf_reinject_lockless(entry, NF_ACCEPT);
++ retval = 0;
++ goto out;
++ }
++ dev->last_rx = jiffies;
++
++ skb = entry->skb;
++ skb_orig = NULL;
++
++ /* skb has owner? => make clone */
++ if (unlikely(skb->destructor)) {
++ skb_orig = skb;
++ skb = skb_clone(skb, GFP_ATOMIC);
++ if (!skb) {
++ retval = -ENOMEM;
++ goto out;
++ }
++ entry->skb = skb;
++ }
++
++ skb->nf_queue_entry = entry;
++
++ dev->stats.rx_bytes += skb->len;
++ dev->stats.rx_packets++;
++
++ txq = dev_pick_tx(dev, skb);
++
++ q = rcu_dereference(txq->qdisc);
++ if (unlikely(!q->enqueue))
++ goto packet_not_eaten_by_imq_dev;
++
++ spin_lock_bh(qdisc_lock(q));
++
++ users = atomic_read(&skb->users);
++
++ skb_shared = skb_get(skb); /* increase reference count by one */
++ skb_save_cb(skb_shared); /* backup skb->cb, as qdisc layer will
++ overwrite it */
++ qdisc_enqueue_root(skb_shared, q); /* might kfree_skb */
++
++ if (likely(atomic_read(&skb_shared->users) == users + 1)) {
++ kfree_skb(skb_shared); /* decrease reference count by one */
++
++ skb->destructor = &imq_skb_destructor;
++
++ /* cloned? */
++ if (skb_orig)
++ kfree_skb(skb_orig); /* free original */
++
++ spin_unlock_bh(qdisc_lock(q));
++
++ /* schedule qdisc dequeue */
++ __netif_schedule(q);
++
++ retval = 0;
++ goto out;
++ } else {
++ skb_restore_cb(skb_shared); /* restore skb->cb */
++ skb->nf_queue_entry = NULL;
++ /* qdisc dropped packet and decreased skb reference count of
++ * skb, so we don't really want to and try refree as that would
++ * actually destroy the skb. */
++ spin_unlock_bh(qdisc_lock(q));
++ goto packet_not_eaten_by_imq_dev;
++ }
++
++packet_not_eaten_by_imq_dev:
++ /* cloned? restore original */
++ if (skb_orig) {
++ kfree_skb(skb);
++ entry->skb = skb_orig;
++ }
++ retval = -1;
++out:
++ return retval;
++}
++
++static struct nf_queue_handler nfqh = {
++ .name = "imq",
++ .outfn = imq_nf_queue,
++};
++
++static unsigned int imq_nf_hook(unsigned int hook, struct sk_buff *pskb,
++ const struct net_device *indev,
++ const struct net_device *outdev,
++ int (*okfn)(struct sk_buff *))
++{
++ if (pskb->imq_flags & IMQ_F_ENQUEUE)
++ return NF_QUEUE;
++
++ return NF_ACCEPT;
++}
++
++static int imq_close(struct net_device *dev)
++{
++ netif_stop_queue(dev);
++ return 0;
++}
++
++static int imq_open(struct net_device *dev)
++{
++ netif_start_queue(dev);
++ return 0;
++}
++
++static const struct net_device_ops imq_netdev_ops = {
++ .ndo_open = imq_open,
++ .ndo_stop = imq_close,
++ .ndo_start_xmit = imq_dev_xmit,
++ .ndo_get_stats = imq_get_stats,
++};
++
++static void imq_setup(struct net_device *dev)
++{
++ dev->netdev_ops = &imq_netdev_ops;
++ dev->type = ARPHRD_VOID;
++ dev->mtu = 16000;
++ dev->tx_queue_len = 11000;
++ dev->flags = IFF_NOARP;
++ dev->features = NETIF_F_SG | NETIF_F_FRAGLIST |
++ NETIF_F_GSO | NETIF_F_HW_CSUM |
++ NETIF_F_HIGHDMA;
++ dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
++}
++
++static int imq_validate(struct nlattr *tb[], struct nlattr *data[])
++{
++ int ret = 0;
++
++ if (tb[IFLA_ADDRESS]) {
++ if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) {
++ ret = -EINVAL;
++ goto end;
++ }
++ if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) {
++ ret = -EADDRNOTAVAIL;
++ goto end;
++ }
++ }
++ return 0;
++end:
++ printk(KERN_WARNING "IMQ: imq_validate failed (%d)\n", ret);
++ return ret;
++}
++
++static struct rtnl_link_ops imq_link_ops __read_mostly = {
++ .kind = "imq",
++ .priv_size = 0,
++ .setup = imq_setup,
++ .validate = imq_validate,
++};
++
++static int __init imq_init_hooks(void)
++{
++ int err;
++
++ nf_register_queue_imq_handler(&nfqh);
++
++ err = nf_register_hook(&imq_ingress_ipv4);
++ if (err)
++ goto err1;
++
++ err = nf_register_hook(&imq_egress_ipv4);
++ if (err)
++ goto err2;
++
++#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
++ err = nf_register_hook(&imq_ingress_ipv6);
++ if (err)
++ goto err3;
++
++ err = nf_register_hook(&imq_egress_ipv6);
++ if (err)
++ goto err4;
++#endif
++
++ return 0;
++
++#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
++err4:
++ nf_unregister_hook(&imq_ingress_ipv6);
++err3:
++ nf_unregister_hook(&imq_egress_ipv4);
++#endif
++err2:
++ nf_unregister_hook(&imq_ingress_ipv4);
++err1:
++ nf_unregister_queue_imq_handler();
++ return err;
++}
++
++static int __init imq_init_one(int index)
++{
++ struct net_device *dev;
++ int ret;
++
++ dev = alloc_netdev(0, "imq%d", imq_setup);
++ if (!dev)
++ return -ENOMEM;
++
++ ret = dev_alloc_name(dev, dev->name);
++ if (ret < 0)
++ goto fail;
++
++ dev->rtnl_link_ops = &imq_link_ops;
++ ret = register_netdevice(dev);
++ if (ret < 0)
++ goto fail;
++
++ return 0;
++fail:
++ free_netdev(dev);
++ return ret;
++}
++
++static int __init imq_init_devs(void)
++{
++ int err, i;
++
++ if (numdevs < 1 || numdevs > IMQ_MAX_DEVS) {
++ printk(KERN_ERR "IMQ: numdevs has to be betweed 1 and %u\n",
++ IMQ_MAX_DEVS);
++ return -EINVAL;
++ }
++
++ rtnl_lock();
++ err = __rtnl_link_register(&imq_link_ops);
++
++ for (i = 0; i < numdevs && !err; i++)
++ err = imq_init_one(i);
++
++ if (err) {
++ __rtnl_link_unregister(&imq_link_ops);
++ memset(imq_devs_cache, 0, sizeof(imq_devs_cache));
++ }
++ rtnl_unlock();
++
++ return err;
++}
++
++static int __init imq_init_module(void)
++{
++ int err;
++
++#if defined(CONFIG_IMQ_NUM_DEVS)
++ BUILD_BUG_ON(CONFIG_IMQ_NUM_DEVS > 16);
++ BUILD_BUG_ON(CONFIG_IMQ_NUM_DEVS < 2);
++ BUILD_BUG_ON(CONFIG_IMQ_NUM_DEVS - 1 > IMQ_F_IFMASK);
++#endif
++
++ err = imq_init_devs();
++ if (err) {
++ printk(KERN_ERR "IMQ: Error trying imq_init_devs(net)\n");
++ return err;
++ }
++
++ err = imq_init_hooks();
++ if (err) {
++ printk(KERN_ERR "IMQ: Error trying imq_init_hooks()\n");
++ rtnl_link_unregister(&imq_link_ops);
++ memset(imq_devs_cache, 0, sizeof(imq_devs_cache));
++ return err;
++ }
++
++ printk(KERN_INFO "IMQ driver loaded successfully.\n");
++
++#if defined(CONFIG_IMQ_BEHAVIOR_BA) || defined(CONFIG_IMQ_BEHAVIOR_BB)
++ printk(KERN_INFO "\tHooking IMQ before NAT on PREROUTING.\n");
++#else
++ printk(KERN_INFO "\tHooking IMQ after NAT on PREROUTING.\n");
++#endif
++#if defined(CONFIG_IMQ_BEHAVIOR_AB) || defined(CONFIG_IMQ_BEHAVIOR_BB)
++ printk(KERN_INFO "\tHooking IMQ before NAT on POSTROUTING.\n");
++#else
++ printk(KERN_INFO "\tHooking IMQ after NAT on POSTROUTING.\n");
++#endif
++
++ return 0;
++}
++
++static void __exit imq_unhook(void)
++{
++#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
++ nf_unregister_hook(&imq_ingress_ipv6);
++ nf_unregister_hook(&imq_egress_ipv6);
++#endif
++ nf_unregister_hook(&imq_ingress_ipv4);
++ nf_unregister_hook(&imq_egress_ipv4);
++
++ nf_unregister_queue_imq_handler();
++}
++
++static void __exit imq_cleanup_devs(void)
++{
++ rtnl_link_unregister(&imq_link_ops);
++ memset(imq_devs_cache, 0, sizeof(imq_devs_cache));
++}
++
++static void __exit imq_exit_module(void)
++{
++ imq_unhook();
++ imq_cleanup_devs();
++ printk(KERN_INFO "IMQ driver unloaded successfully.\n");
++}
++
++module_init(imq_init_module);
++module_exit(imq_exit_module);
++
++module_param(numdevs, int, 0);
++MODULE_PARM_DESC(numdevs, "number of IMQ devices (how many imq* devices will "
++ "be created)");
++MODULE_AUTHOR("http://www.linuximq.net");
++MODULE_DESCRIPTION("Pseudo-driver for the intermediate queue device. See "
++ "http://www.linuximq.net/ for more information.");
++MODULE_LICENSE("GPL");
++MODULE_ALIAS_RTNL_LINK("imq");
++
+--- a/drivers/net/Kconfig
++++ b/drivers/net/Kconfig
+@@ -121,6 +121,129 @@ config EQUALIZER
+ To compile this driver as a module, choose M here: the module
+ will be called eql. If unsure, say N.
+
++config IMQ
++ tristate "IMQ (intermediate queueing device) support"
++ depends on NETDEVICES && NETFILTER
++ ---help---
++ The IMQ device(s) is used as placeholder for QoS queueing
++ disciplines. Every packet entering/leaving the IP stack can be
++ directed through the IMQ device where it's enqueued/dequeued to the
++ attached qdisc. This allows you to treat network devices as classes
++ and distribute bandwidth among them. Iptables is used to specify
++ through which IMQ device, if any, packets travel.
++
++ More information at: http://www.linuximq.net/
++
++ To compile this driver as a module, choose M here: the module
++ will be called imq. If unsure, say N.
++
++choice
++ prompt "IMQ behavior (PRE/POSTROUTING)"
++ depends on IMQ
++ default IMQ_BEHAVIOR_AB
++ help
++
++ This settings defines how IMQ behaves in respect to its
++ hooking in PREROUTING and POSTROUTING.
++
++ IMQ can work in any of the following ways:
++
++ PREROUTING | POSTROUTING
++ -----------------|-------------------
++ #1 After NAT | After NAT
++ #2 After NAT | Before NAT
++ #3 Before NAT | After NAT
++ #4 Before NAT | Before NAT
++
++ The default behavior is to hook before NAT on PREROUTING
++ and after NAT on POSTROUTING (#3).
++
++ This settings are specially usefull when trying to use IMQ
++ to shape NATed clients.
++
++ More information can be found at: www.linuximq.net
++
++ If not sure leave the default settings alone.
++
++config IMQ_BEHAVIOR_AA
++ bool "IMQ AA"
++ help
++ This settings defines how IMQ behaves in respect to its
++ hooking in PREROUTING and POSTROUTING.
++
++ Choosing this option will make IMQ hook like this:
++
++ PREROUTING: After NAT
++ POSTROUTING: After NAT
++
++ More information can be found at: www.linuximq.net
++
++ If not sure leave the default settings alone.
++
++config IMQ_BEHAVIOR_AB
++ bool "IMQ AB"
++ help
++ This settings defines how IMQ behaves in respect to its
++ hooking in PREROUTING and POSTROUTING.
++
++ Choosing this option will make IMQ hook like this:
++
++ PREROUTING: After NAT
++ POSTROUTING: Before NAT
++
++ More information can be found at: www.linuximq.net
++
++ If not sure leave the default settings alone.
++
++config IMQ_BEHAVIOR_BA
++ bool "IMQ BA"
++ help
++ This settings defines how IMQ behaves in respect to its
++ hooking in PREROUTING and POSTROUTING.
++
++ Choosing this option will make IMQ hook like this:
++
++ PREROUTING: Before NAT
++ POSTROUTING: After NAT
++
++ More information can be found at: www.linuximq.net
++
++ If not sure leave the default settings alone.
++
++config IMQ_BEHAVIOR_BB
++ bool "IMQ BB"
++ help
++ This settings defines how IMQ behaves in respect to its
++ hooking in PREROUTING and POSTROUTING.
++
++ Choosing this option will make IMQ hook like this:
++
++ PREROUTING: Before NAT
++ POSTROUTING: Before NAT
++
++ More information can be found at: www.linuximq.net
++
++ If not sure leave the default settings alone.
++
++endchoice
++
++config IMQ_NUM_DEVS
++
++ int "Number of IMQ devices"
++ range 2 16
++ depends on IMQ
++ default "16"
++ help
++
++ This settings defines how many IMQ devices will be
++ created.
++
++ The default value is 16.
++
++ More information can be found at: www.linuximq.net
++
++ If not sure leave the default settings alone.
++
+ config TUN
+ tristate "Universal TUN/TAP device driver support"
+ select CRC32
+--- a/drivers/net/Makefile
++++ b/drivers/net/Makefile
+@@ -169,6 +169,7 @@ obj-$(CONFIG_SLHC) += slhc.o
+ obj-$(CONFIG_XEN_NETDEV_FRONTEND) += xen-netfront.o
+
+ obj-$(CONFIG_DUMMY) += dummy.o
++obj-$(CONFIG_IMQ) += imq.o
+ obj-$(CONFIG_IFB) += ifb.o
+ obj-$(CONFIG_MACVLAN) += macvlan.o
+ obj-$(CONFIG_MACVTAP) += macvtap.o
+--- /dev/null
++++ b/include/linux/imq.h
+@@ -0,0 +1,13 @@
++#ifndef _IMQ_H
++#define _IMQ_H
++
++/* IFMASK (16 device indexes, 0 to 15) and flag(s) fit in 5 bits */
++#define IMQ_F_BITS 5
++
++#define IMQ_F_IFMASK 0x0f
++#define IMQ_F_ENQUEUE 0x10
++
++#define IMQ_MAX_DEVS (IMQ_F_IFMASK + 1)
++
++#endif /* _IMQ_H */
++
+--- a/include/linux/netdevice.h
++++ b/include/linux/netdevice.h
+@@ -1295,6 +1295,7 @@ extern int dev_alloc_name(struct net_de
+ extern int dev_open(struct net_device *dev);
+ extern int dev_close(struct net_device *dev);
+ extern void dev_disable_lro(struct net_device *dev);
++extern struct netdev_queue *dev_pick_tx(struct net_device *dev, struct sk_buff *skb);
+ extern int dev_queue_xmit(struct sk_buff *skb);
+ extern int register_netdevice(struct net_device *dev);
+ extern void unregister_netdevice_queue(struct net_device *dev,
+--- /dev/null
++++ b/include/linux/netfilter/xt_IMQ.h
+@@ -0,0 +1,9 @@
++#ifndef _XT_IMQ_H
++#define _XT_IMQ_H
++
++struct xt_imq_info {
++ unsigned int todev; /* target imq device */
++};
++
++#endif /* _XT_IMQ_H */
++
+--- /dev/null
++++ b/include/linux/netfilter_ipv4/ipt_IMQ.h
+@@ -0,0 +1,10 @@
++#ifndef _IPT_IMQ_H
++#define _IPT_IMQ_H
++
++/* Backwards compatibility for old userspace */
++#include <linux/netfilter/xt_IMQ.h>
++
++#define ipt_imq_info xt_imq_info
++
++#endif /* _IPT_IMQ_H */
++
+--- /dev/null
++++ b/include/linux/netfilter_ipv6/ip6t_IMQ.h
+@@ -0,0 +1,10 @@
++#ifndef _IP6T_IMQ_H
++#define _IP6T_IMQ_H
++
++/* Backwards compatibility for old userspace */
++#include <linux/netfilter/xt_IMQ.h>
++
++#define ip6t_imq_info xt_imq_info
++
++#endif /* _IP6T_IMQ_H */
++
+--- a/include/linux/skbuff.h
++++ b/include/linux/skbuff.h
+@@ -29,6 +29,9 @@
+ #include <linux/rcupdate.h>
+ #include <linux/dmaengine.h>
+ #include <linux/hrtimer.h>
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++#include <linux/imq.h>
++#endif
+
+ /* Don't change this without changing skb_csum_unnecessary! */
+ #define CHECKSUM_NONE 0
+@@ -330,6 +333,9 @@ struct sk_buff {
+ * first. This is owned by whoever has the skb queued ATM.
+ */
+ char cb[48] __aligned(8);
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ void *cb_next;
++#endif
+
+ unsigned long _skb_refdst;
+ #ifdef CONFIG_XFRM
+@@ -366,6 +372,9 @@ struct sk_buff {
+ struct nf_conntrack *nfct;
+ struct sk_buff *nfct_reasm;
+ #endif
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ struct nf_queue_entry *nf_queue_entry;
++#endif
+ #ifdef CONFIG_BRIDGE_NETFILTER
+ struct nf_bridge_info *nf_bridge;
+ #endif
+@@ -392,6 +401,10 @@ struct sk_buff {
+
+ /* 0/14 bit hole */
+
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ __u8 imq_flags:IMQ_F_BITS;
++#endif
++
+ #ifdef CONFIG_NET_DMA
+ dma_cookie_t dma_cookie;
+ #endif
+@@ -490,6 +503,12 @@ static inline struct rtable *skb_rtable(
+ return (struct rtable *)skb_dst(skb);
+ }
+
++
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++extern int skb_save_cb(struct sk_buff *skb);
++extern int skb_restore_cb(struct sk_buff *skb);
++#endif
++
+ extern void kfree_skb(struct sk_buff *skb);
+ extern void consume_skb(struct sk_buff *skb);
+ extern void __kfree_skb(struct sk_buff *skb);
+@@ -2096,6 +2115,10 @@ static inline void __nf_copy(struct sk_b
+ dst->nfct_reasm = src->nfct_reasm;
+ nf_conntrack_get_reasm(src->nfct_reasm);
+ #endif
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ dst->imq_flags = src->imq_flags;
++ dst->nf_queue_entry = src->nf_queue_entry;
++#endif
+ #ifdef CONFIG_BRIDGE_NETFILTER
+ dst->nf_bridge = src->nf_bridge;
+ nf_bridge_get(src->nf_bridge);
+--- a/include/net/netfilter/nf_queue.h
++++ b/include/net/netfilter/nf_queue.h
+@@ -13,6 +13,12 @@ struct nf_queue_entry {
+ struct net_device *indev;
+ struct net_device *outdev;
+ int (*okfn)(struct sk_buff *);
++
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ int (*next_outfn)(struct nf_queue_entry *entry,
++ unsigned int queuenum);
++ unsigned int next_queuenum;
++#endif
+ };
+
+ #define nf_queue_entry_reroute(x) ((void *)x + sizeof(struct nf_queue_entry))
+@@ -30,5 +36,11 @@ extern int nf_unregister_queue_handler(u
+ const struct nf_queue_handler *qh);
+ extern void nf_unregister_queue_handlers(const struct nf_queue_handler *qh);
+ extern void nf_reinject(struct nf_queue_entry *entry, unsigned int verdict);
++extern void nf_queue_entry_release_refs(struct nf_queue_entry *entry);
++
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++extern void nf_register_queue_imq_handler(const struct nf_queue_handler *qh);
++extern void nf_unregister_queue_imq_handler(void);
++#endif
+
+ #endif /* _NF_QUEUE_H */
+--- a/net/core/dev.c
++++ b/net/core/dev.c
+@@ -98,6 +98,9 @@
+ #include <net/net_namespace.h>
+ #include <net/sock.h>
+ #include <linux/rtnetlink.h>
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++#include <linux/imq.h>
++#endif
+ #include <linux/proc_fs.h>
+ #include <linux/seq_file.h>
+ #include <linux/stat.h>
+@@ -1942,7 +1945,11 @@ int dev_hard_start_xmit(struct sk_buff *
+ int rc = NETDEV_TX_OK;
+
+ if (likely(!skb->next)) {
+- if (!list_empty(&ptype_all))
++ if (!list_empty(&ptype_all)
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ && !(skb->imq_flags & IMQ_F_ENQUEUE)
++#endif
++ )
+ dev_queue_xmit_nit(skb, dev);
+
+ /*
+@@ -2054,8 +2061,7 @@ static inline u16 dev_cap_txqueue(struct
+ return queue_index;
+ }
+
+-static struct netdev_queue *dev_pick_tx(struct net_device *dev,
+- struct sk_buff *skb)
++struct netdev_queue *dev_pick_tx(struct net_device *dev, struct sk_buff *skb)
+ {
+ int queue_index;
+ const struct net_device_ops *ops = dev->netdev_ops;
+@@ -2084,6 +2090,7 @@ static struct netdev_queue *dev_pick_tx(
+ skb_set_queue_mapping(skb, queue_index);
+ return netdev_get_tx_queue(dev, queue_index);
+ }
++EXPORT_SYMBOL(dev_pick_tx);
+
+ static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
+ struct net_device *dev,
+--- a/net/core/skbuff.c
++++ b/net/core/skbuff.c
+@@ -72,6 +72,9 @@
+
+ static struct kmem_cache *skbuff_head_cache __read_mostly;
+ static struct kmem_cache *skbuff_fclone_cache __read_mostly;
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++static struct kmem_cache *skbuff_cb_store_cache __read_mostly;
++#endif
+
+ static void sock_pipe_buf_release(struct pipe_inode_info *pipe,
+ struct pipe_buffer *buf)
+@@ -91,6 +94,83 @@ static int sock_pipe_buf_steal(struct pi
+ return 1;
+ }
+
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++/* Control buffer save/restore for IMQ devices */
++struct skb_cb_table {
++ void *cb_next;
++ atomic_t refcnt;
++ char cb[48];
++};
++
++static DEFINE_SPINLOCK(skb_cb_store_lock);
++
++int skb_save_cb(struct sk_buff *skb)
++{
++ struct skb_cb_table *next;
++
++ next = kmem_cache_alloc(skbuff_cb_store_cache, GFP_ATOMIC);
++ if (!next)
++ return -ENOMEM;
++
++ BUILD_BUG_ON(sizeof(skb->cb) != sizeof(next->cb));
++
++ memcpy(next->cb, skb->cb, sizeof(skb->cb));
++ next->cb_next = skb->cb_next;
++
++ atomic_set(&next->refcnt, 1);
++
++ skb->cb_next = next;
++ return 0;
++}
++EXPORT_SYMBOL(skb_save_cb);
++
++int skb_restore_cb(struct sk_buff *skb)
++{
++ struct skb_cb_table *next;
++
++ if (!skb->cb_next)
++ return 0;
++
++ next = skb->cb_next;
++
++ BUILD_BUG_ON(sizeof(skb->cb) != sizeof(next->cb));
++
++ memcpy(skb->cb, next->cb, sizeof(skb->cb));
++ skb->cb_next = next->cb_next;
++
++ spin_lock(&skb_cb_store_lock);
++
++ if (atomic_dec_and_test(&next->refcnt)) {
++ kmem_cache_free(skbuff_cb_store_cache, next);
++ }
++
++ spin_unlock(&skb_cb_store_lock);
++
++ return 0;
++}
++EXPORT_SYMBOL(skb_restore_cb);
++
++static void skb_copy_stored_cb(struct sk_buff *new, const struct sk_buff *__old)
++{
++ struct skb_cb_table *next;
++ struct sk_buff *old;
++
++ if (!__old->cb_next) {
++ new->cb_next = NULL;
++ return;
++ }
++
++ spin_lock(&skb_cb_store_lock);
++
++ old = (struct sk_buff *)__old;
++
++ next = old->cb_next;
++ atomic_inc(&next->refcnt);
++ new->cb_next = next;
++
++ spin_unlock(&skb_cb_store_lock);
++}
++#endif
+
+ /* Pipe buffer operations for a socket. */
+ static const struct pipe_buf_operations sock_pipe_buf_ops = {
+@@ -391,6 +471,26 @@ static void skb_release_head_state(struc
+ WARN_ON(in_irq());
+ skb->destructor(skb);
+ }
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ /* This should not happen. When it does, avoid memleak by restoring
++ the chain of cb-backups. */
++ while(skb->cb_next != NULL) {
++ if (net_ratelimit())
++ printk(KERN_WARNING "IMQ: kfree_skb: skb->cb_next: "
++ "%08x\n", (unsigned int)skb->cb_next);
++
++ skb_restore_cb(skb);
++ }
++ /* This should not happen either, nf_queue_entry is nullified in
++ * imq_dev_xmit(). If we have non-NULL nf_queue_entry then we are
++ * leaking entry pointers, maybe memory. We don't know if this is
++ * pointer to already freed memory, or should this be freed.
++ * If this happens we need to add refcounting, etc for nf_queue_entry.
++ */
++ if (skb->nf_queue_entry && net_ratelimit())
++ printk(KERN_WARNING
++ "IMQ: kfree_skb: skb->nf_queue_entry != NULL");
++#endif
+ #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
+ nf_conntrack_put(skb->nfct);
+ nf_conntrack_put_reasm(skb->nfct_reasm);
+@@ -526,6 +626,9 @@ static void __copy_skb_header(struct sk_
+ new->sp = secpath_get(old->sp);
+ #endif
+ memcpy(new->cb, old->cb, sizeof(old->cb));
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ skb_copy_stored_cb(new, old);
++#endif
+ new->csum = old->csum;
+ new->local_df = old->local_df;
+ new->pkt_type = old->pkt_type;
+@@ -2779,6 +2882,13 @@ void __init skb_init(void)
+ 0,
+ SLAB_HWCACHE_ALIGN|SLAB_PANIC,
+ NULL);
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ skbuff_cb_store_cache = kmem_cache_create("skbuff_cb_store_cache",
++ sizeof(struct skb_cb_table),
++ 0,
++ SLAB_HWCACHE_ALIGN|SLAB_PANIC,
++ NULL);
++#endif
+ }
+
+ /**
+--- a/net/netfilter/Kconfig
++++ b/net/netfilter/Kconfig
+@@ -455,6 +455,18 @@ config NETFILTER_XT_TARGET_LED
+ For more information on the LEDs available on your system, see
+ Documentation/leds-class.txt
+
++config NETFILTER_XT_TARGET_IMQ
++ tristate '"IMQ" target support'
++ depends on NETFILTER_XTABLES
++ depends on IP_NF_MANGLE || IP6_NF_MANGLE
++ select IMQ
++ default m if NETFILTER_ADVANCED=n
++ help
++ This option adds a `IMQ' target which is used to specify if and
++ to which imq device packets should get enqueued/dequeued.
++
++ To compile it as a module, choose M here. If unsure, say N.
++
+ config NETFILTER_XT_TARGET_MARK
+ tristate '"MARK" target support'
+ depends on NETFILTER_ADVANCED
+--- a/net/netfilter/Makefile
++++ b/net/netfilter/Makefile
+@@ -51,6 +51,7 @@ obj-$(CONFIG_NETFILTER_XT_TARGET_CONNSEC
+ obj-$(CONFIG_NETFILTER_XT_TARGET_CT) += xt_CT.o
+ obj-$(CONFIG_NETFILTER_XT_TARGET_DSCP) += xt_DSCP.o
+ obj-$(CONFIG_NETFILTER_XT_TARGET_HL) += xt_HL.o
++obj-$(CONFIG_NETFILTER_XT_TARGET_IMQ) += xt_IMQ.o
+ obj-$(CONFIG_NETFILTER_XT_TARGET_LED) += xt_LED.o
+ obj-$(CONFIG_NETFILTER_XT_TARGET_NFLOG) += xt_NFLOG.o
+ obj-$(CONFIG_NETFILTER_XT_TARGET_NFQUEUE) += xt_NFQUEUE.o
+--- a/net/netfilter/nf_queue.c
++++ b/net/netfilter/nf_queue.c
+@@ -22,6 +22,26 @@ static const struct nf_queue_handler *qu
+
+ static DEFINE_MUTEX(queue_handler_mutex);
+
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++static const struct nf_queue_handler *queue_imq_handler;
++
++void nf_register_queue_imq_handler(const struct nf_queue_handler *qh)
++{
++ mutex_lock(&queue_handler_mutex);
++ rcu_assign_pointer(queue_imq_handler, qh);
++ mutex_unlock(&queue_handler_mutex);
++}
++EXPORT_SYMBOL(nf_register_queue_imq_handler);
++
++void nf_unregister_queue_imq_handler(void)
++{
++ mutex_lock(&queue_handler_mutex);
++ rcu_assign_pointer(queue_imq_handler, NULL);
++ mutex_unlock(&queue_handler_mutex);
++}
++EXPORT_SYMBOL(nf_unregister_queue_imq_handler);
++#endif
++
+ /* return EBUSY when somebody else is registered, return EEXIST if the
+ * same handler is registered, return 0 in case of success. */
+ int nf_register_queue_handler(u_int8_t pf, const struct nf_queue_handler *qh)
+@@ -82,7 +102,7 @@ void nf_unregister_queue_handlers(const
+ }
+ EXPORT_SYMBOL_GPL(nf_unregister_queue_handlers);
+
+-static void nf_queue_entry_release_refs(struct nf_queue_entry *entry)
++void nf_queue_entry_release_refs(struct nf_queue_entry *entry)
+ {
+ /* Release those devices we held, or Alexey will kill me. */
+ if (entry->indev)
+@@ -102,6 +122,7 @@ static void nf_queue_entry_release_refs(
+ /* Drop reference to owner of hook which queued us. */
+ module_put(entry->elem->owner);
+ }
++EXPORT_SYMBOL_GPL(nf_queue_entry_release_refs);
+
+ /*
+ * Any packet that leaves via this function must come back
+@@ -123,12 +144,26 @@ static int __nf_queue(struct sk_buff *sk
+ #endif
+ const struct nf_afinfo *afinfo;
+ const struct nf_queue_handler *qh;
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ const struct nf_queue_handler *qih = NULL;
++#endif
+
+ /* QUEUE == DROP if noone is waiting, to be safe. */
+ rcu_read_lock();
+
+ qh = rcu_dereference(queue_handler[pf]);
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
++ if (pf == PF_INET || pf == PF_INET6)
++#else
++ if (pf == PF_INET)
++#endif
++ qih = rcu_dereference(queue_imq_handler);
++
++ if (!qh && !qih)
++#else /* !IMQ */
+ if (!qh)
++#endif
+ goto err_unlock;
+
+ afinfo = nf_get_afinfo(pf);
+@@ -147,6 +182,10 @@ static int __nf_queue(struct sk_buff *sk
+ .indev = indev,
+ .outdev = outdev,
+ .okfn = okfn,
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ .next_outfn = qh ? qh->outfn : NULL,
++ .next_queuenum = queuenum,
++#endif
+ };
+
+ /* If it's going away, ignore hook. */
+@@ -173,8 +212,19 @@ static int __nf_queue(struct sk_buff *sk
+ #endif
+ skb_dst_force(skb);
+ afinfo->saveroute(skb, entry);
++
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ if (qih) {
++ status = qih->outfn(entry, queuenum);
++ goto imq_skip_queue;
++ }
++#endif
++
+ status = qh->outfn(entry, queuenum);
+
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++imq_skip_queue:
++#endif
+ rcu_read_unlock();
+
+ if (status < 0) {
+--- /dev/null
++++ b/net/netfilter/xt_IMQ.c
+@@ -0,0 +1,73 @@
++/*
++ * This target marks packets to be enqueued to an imq device
++ */
++#include <linux/module.h>
++#include <linux/skbuff.h>
++#include <linux/netfilter/x_tables.h>
++#include <linux/netfilter/xt_IMQ.h>
++#include <linux/imq.h>
++
++static unsigned int imq_target(struct sk_buff *pskb,
++ const struct xt_action_param *par)
++{
++ const struct xt_imq_info *mr = par->targinfo;
++
++ pskb->imq_flags = (mr->todev & IMQ_F_IFMASK) | IMQ_F_ENQUEUE;
++
++ return XT_CONTINUE;
++}
++
++static int imq_checkentry(const struct xt_tgchk_param *par)
++{
++ struct xt_imq_info *mr = par->targinfo;
++
++ if (mr->todev > IMQ_MAX_DEVS - 1) {
++ printk(KERN_WARNING
++ "IMQ: invalid device specified, highest is %u\n",
++ IMQ_MAX_DEVS - 1);
++ return -EINVAL;
++ }
++
++ return 0;
++}
++
++static struct xt_target xt_imq_reg[] __read_mostly = {
++ {
++ .name = "IMQ",
++ .family = AF_INET,
++ .checkentry = imq_checkentry,
++ .target = imq_target,
++ .targetsize = sizeof(struct xt_imq_info),
++ .table = "mangle",
++ .me = THIS_MODULE
++ },
++ {
++ .name = "IMQ",
++ .family = AF_INET6,
++ .checkentry = imq_checkentry,
++ .target = imq_target,
++ .targetsize = sizeof(struct xt_imq_info),
++ .table = "mangle",
++ .me = THIS_MODULE
++ },
++};
++
++static int __init imq_init(void)
++{
++ return xt_register_targets(xt_imq_reg, ARRAY_SIZE(xt_imq_reg));
++}
++
++static void __exit imq_fini(void)
++{
++ xt_unregister_targets(xt_imq_reg, ARRAY_SIZE(xt_imq_reg));
++}
++
++module_init(imq_init);
++module_exit(imq_fini);
++
++MODULE_AUTHOR("http://www.linuximq.net");
++MODULE_DESCRIPTION("Pseudo-driver for the intermediate queue device. See http://www.linuximq.net/ for more information.");
++MODULE_LICENSE("GPL");
++MODULE_ALIAS("ipt_IMQ");
++MODULE_ALIAS("ip6t_IMQ");
++
--- /dev/null
+--- /dev/null
++++ b/drivers/net/imq.c
+@@ -0,0 +1,638 @@
++/*
++ * Pseudo-driver for the intermediate queue device.
++ *
++ * 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.
++ *
++ * Authors: Patrick McHardy, <kaber@trash.net>
++ *
++ * The first version was written by Martin Devera, <devik@cdi.cz>
++ *
++ * Credits: Jan Rafaj <imq2t@cedric.vabo.cz>
++ * - Update patch to 2.4.21
++ * Sebastian Strollo <sstrollo@nortelnetworks.com>
++ * - Fix "Dead-loop on netdevice imq"-issue
++ * Marcel Sebek <sebek64@post.cz>
++ * - Update to 2.6.2-rc1
++ *
++ * After some time of inactivity there is a group taking care
++ * of IMQ again: http://www.linuximq.net
++ *
++ *
++ * 2004/06/30 - New version of IMQ patch to kernels <=2.6.7
++ * including the following changes:
++ *
++ * - Correction of ipv6 support "+"s issue (Hasso Tepper)
++ * - Correction of imq_init_devs() issue that resulted in
++ * kernel OOPS unloading IMQ as module (Norbert Buchmuller)
++ * - Addition of functionality to choose number of IMQ devices
++ * during kernel config (Andre Correa)
++ * - Addition of functionality to choose how IMQ hooks on
++ * PRE and POSTROUTING (after or before NAT) (Andre Correa)
++ * - Cosmetic corrections (Norbert Buchmuller) (Andre Correa)
++ *
++ *
++ * 2005/12/16 - IMQ versions between 2.6.7 and 2.6.13 were
++ * released with almost no problems. 2.6.14-x was released
++ * with some important changes: nfcache was removed; After
++ * some weeks of trouble we figured out that some IMQ fields
++ * in skb were missing in skbuff.c - skb_clone and copy_skb_header.
++ * These functions are correctly patched by this new patch version.
++ *
++ * Thanks for all who helped to figure out all the problems with
++ * 2.6.14.x: Patrick McHardy, Rune Kock, VeNoMouS, Max CtRiX,
++ * Kevin Shanahan, Richard Lucassen, Valery Dachev (hopefully
++ * I didn't forget anybody). I apologize again for my lack of time.
++ *
++ *
++ * 2008/06/17 - 2.6.25 - Changed imq.c to use qdisc_run() instead
++ * of qdisc_restart() and moved qdisc_run() to tasklet to avoid
++ * recursive locking. New initialization routines to fix 'rmmod' not
++ * working anymore. Used code from ifb.c. (Jussi Kivilinna)
++ *
++ * 2008/08/06 - 2.6.26 - (JK)
++ * - Replaced tasklet with 'netif_schedule()'.
++ * - Cleaned up and added comments for imq_nf_queue().
++ *
++ * 2009/04/12
++ * - Add skb_save_cb/skb_restore_cb helper functions for backuping
++ * control buffer. This is needed because qdisc-layer on kernels
++ * 2.6.27 and newer overwrite control buffer. (Jussi Kivilinna)
++ * - Add better locking for IMQ device. Hopefully this will solve
++ * SMP issues. (Jussi Kivilinna)
++ * - Port to 2.6.27
++ * - Port to 2.6.28
++ * - Port to 2.6.29 + fix rmmod not working
++ *
++ * 2009/04/20 - (Jussi Kivilinna)
++ * - Use netdevice feature flags to avoid extra packet handling
++ * by core networking layer and possibly increase performance.
++ *
++ * 2009/09/26 - (Jussi Kivilinna)
++ * - Add imq_nf_reinject_lockless to fix deadlock with
++ * imq_nf_queue/imq_nf_reinject.
++ *
++ * 2009/12/08 - (Jussi Kivilinna)
++ * - Port to 2.6.32
++ * - Add check for skb->nf_queue_entry==NULL in imq_dev_xmit()
++ * - Also add better error checking for skb->nf_queue_entry usage
++ *
++ * 2010/02/25 - (Jussi Kivilinna)
++ * - Port to 2.6.33
++ *
++ * 2010/08/12 - (Jussi Kivilinna)
++ * - Port to 2.6.35
++ *
++ * Also, many thanks to pablo Sebastian Greco for making the initial
++ * patch and to those who helped the testing.
++ *
++ * More info at: http://www.linuximq.net/ (Andre Correa)
++ */
++
++#include <linux/module.h>
++#include <linux/kernel.h>
++#include <linux/moduleparam.h>
++#include <linux/list.h>
++#include <linux/skbuff.h>
++#include <linux/netdevice.h>
++#include <linux/etherdevice.h>
++#include <linux/rtnetlink.h>
++#include <linux/if_arp.h>
++#include <linux/netfilter.h>
++#include <linux/netfilter_ipv4.h>
++#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
++ #include <linux/netfilter_ipv6.h>
++#endif
++#include <linux/imq.h>
++#include <net/pkt_sched.h>
++#include <net/netfilter/nf_queue.h>
++
++static nf_hookfn imq_nf_hook;
++
++static struct nf_hook_ops imq_ingress_ipv4 = {
++ .hook = imq_nf_hook,
++ .owner = THIS_MODULE,
++ .pf = PF_INET,
++ .hooknum = NF_INET_PRE_ROUTING,
++#if defined(CONFIG_IMQ_BEHAVIOR_BA) || defined(CONFIG_IMQ_BEHAVIOR_BB)
++ .priority = NF_IP_PRI_MANGLE + 1
++#else
++ .priority = NF_IP_PRI_NAT_DST + 1
++#endif
++};
++
++static struct nf_hook_ops imq_egress_ipv4 = {
++ .hook = imq_nf_hook,
++ .owner = THIS_MODULE,
++ .pf = PF_INET,
++ .hooknum = NF_INET_POST_ROUTING,
++#if defined(CONFIG_IMQ_BEHAVIOR_AA) || defined(CONFIG_IMQ_BEHAVIOR_BA)
++ .priority = NF_IP_PRI_LAST
++#else
++ .priority = NF_IP_PRI_NAT_SRC - 1
++#endif
++};
++
++#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
++static struct nf_hook_ops imq_ingress_ipv6 = {
++ .hook = imq_nf_hook,
++ .owner = THIS_MODULE,
++ .pf = PF_INET6,
++ .hooknum = NF_INET_PRE_ROUTING,
++#if defined(CONFIG_IMQ_BEHAVIOR_BA) || defined(CONFIG_IMQ_BEHAVIOR_BB)
++ .priority = NF_IP6_PRI_MANGLE + 1
++#else
++ .priority = NF_IP6_PRI_NAT_DST + 1
++#endif
++};
++
++static struct nf_hook_ops imq_egress_ipv6 = {
++ .hook = imq_nf_hook,
++ .owner = THIS_MODULE,
++ .pf = PF_INET6,
++ .hooknum = NF_INET_POST_ROUTING,
++#if defined(CONFIG_IMQ_BEHAVIOR_AA) || defined(CONFIG_IMQ_BEHAVIOR_BA)
++ .priority = NF_IP6_PRI_LAST
++#else
++ .priority = NF_IP6_PRI_NAT_SRC - 1
++#endif
++};
++#endif
++
++#if defined(CONFIG_IMQ_NUM_DEVS)
++static unsigned int numdevs = CONFIG_IMQ_NUM_DEVS;
++#else
++static unsigned int numdevs = IMQ_MAX_DEVS;
++#endif
++
++static DEFINE_SPINLOCK(imq_nf_queue_lock);
++
++static struct net_device *imq_devs_cache[IMQ_MAX_DEVS];
++
++
++static struct net_device_stats *imq_get_stats(struct net_device *dev)
++{
++ return &dev->stats;
++}
++
++/* called for packets kfree'd in qdiscs at places other than enqueue */
++static void imq_skb_destructor(struct sk_buff *skb)
++{
++ struct nf_queue_entry *entry = skb->nf_queue_entry;
++
++ skb->nf_queue_entry = NULL;
++
++ if (entry) {
++ nf_queue_entry_release_refs(entry);
++ kfree(entry);
++ }
++
++ skb_restore_cb(skb); /* kfree backup */
++}
++
++/* locking not needed when called from imq_nf_queue */
++static void imq_nf_reinject_lockless(struct nf_queue_entry *entry,
++ unsigned int verdict)
++{
++ int status;
++
++ if (!entry->next_outfn) {
++ nf_reinject(entry, verdict);
++ return;
++ }
++
++ status = entry->next_outfn(entry, entry->next_queuenum);
++ if (status < 0) {
++ nf_queue_entry_release_refs(entry);
++ kfree_skb(entry->skb);
++ kfree(entry);
++ }
++}
++
++static void imq_nf_reinject(struct nf_queue_entry *entry, unsigned int verdict)
++{
++ int status;
++
++ if (!entry->next_outfn) {
++ spin_lock_bh(&imq_nf_queue_lock);
++ nf_reinject(entry, verdict);
++ spin_unlock_bh(&imq_nf_queue_lock);
++ return;
++ }
++
++ rcu_read_lock();
++ local_bh_disable();
++ status = entry->next_outfn(entry, entry->next_queuenum);
++ local_bh_enable();
++ if (status < 0) {
++ nf_queue_entry_release_refs(entry);
++ kfree_skb(entry->skb);
++ kfree(entry);
++ }
++
++ rcu_read_unlock();
++}
++
++static netdev_tx_t imq_dev_xmit(struct sk_buff *skb, struct net_device *dev)
++{
++ struct nf_queue_entry *entry = skb->nf_queue_entry;
++
++ skb->nf_queue_entry = NULL;
++ dev->trans_start = jiffies;
++
++ dev->stats.tx_bytes += skb->len;
++ dev->stats.tx_packets++;
++
++ if (entry == NULL) {
++ /* We don't know what is going on here.. packet is queued for
++ * imq device, but (probably) not by us.
++ *
++ * If this packet was not send here by imq_nf_queue(), then
++ * skb_save_cb() was not used and skb_free() should not show:
++ * WARNING: IMQ: kfree_skb: skb->cb_next:..
++ * and/or
++ * WARNING: IMQ: kfree_skb: skb->nf_queue_entry...
++ *
++ * However if this message is shown, then IMQ is somehow broken
++ * and you should report this to linuximq.net.
++ */
++
++ /* imq_dev_xmit is black hole that eats all packets, report that
++ * we eat this packet happily and increase dropped counters.
++ */
++
++ dev->stats.tx_dropped++;
++ dev_kfree_skb(skb);
++
++ return NETDEV_TX_OK;
++ }
++
++ skb_restore_cb(skb); /* restore skb->cb */
++
++ skb->imq_flags = 0;
++ skb->destructor = NULL;
++
++ imq_nf_reinject(entry, NF_ACCEPT);
++
++ return NETDEV_TX_OK;
++}
++
++static int imq_nf_queue(struct nf_queue_entry *entry, unsigned queue_num)
++{
++ struct net_device *dev;
++ struct sk_buff *skb_orig, *skb, *skb_shared;
++ struct Qdisc *q;
++ struct netdev_queue *txq;
++ int users, index;
++ int retval = -EINVAL;
++
++ index = entry->skb->imq_flags & IMQ_F_IFMASK;
++ if (unlikely(index > numdevs - 1)) {
++ if (net_ratelimit())
++ printk(KERN_WARNING
++ "IMQ: invalid device specified, highest is %u\n",
++ numdevs - 1);
++ retval = -EINVAL;
++ goto out;
++ }
++
++ /* check for imq device by index from cache */
++ dev = imq_devs_cache[index];
++ if (unlikely(!dev)) {
++ char buf[8];
++
++ /* get device by name and cache result */
++ snprintf(buf, sizeof(buf), "imq%d", index);
++ dev = dev_get_by_name(&init_net, buf);
++ if (!dev) {
++ /* not found ?!*/
++ BUG();
++ retval = -ENODEV;
++ goto out;
++ }
++
++ imq_devs_cache[index] = dev;
++ dev_put(dev);
++ }
++
++ if (unlikely(!(dev->flags & IFF_UP))) {
++ entry->skb->imq_flags = 0;
++ imq_nf_reinject_lockless(entry, NF_ACCEPT);
++ retval = 0;
++ goto out;
++ }
++ dev->last_rx = jiffies;
++
++ skb = entry->skb;
++ skb_orig = NULL;
++
++ /* skb has owner? => make clone */
++ if (unlikely(skb->destructor)) {
++ skb_orig = skb;
++ skb = skb_clone(skb, GFP_ATOMIC);
++ if (!skb) {
++ retval = -ENOMEM;
++ goto out;
++ }
++ entry->skb = skb;
++ }
++
++ skb->nf_queue_entry = entry;
++
++ dev->stats.rx_bytes += skb->len;
++ dev->stats.rx_packets++;
++
++ txq = dev_pick_tx(dev, skb);
++
++ q = rcu_dereference(txq->qdisc);
++ if (unlikely(!q->enqueue))
++ goto packet_not_eaten_by_imq_dev;
++
++ spin_lock_bh(qdisc_lock(q));
++
++ users = atomic_read(&skb->users);
++
++ skb_shared = skb_get(skb); /* increase reference count by one */
++ skb_save_cb(skb_shared); /* backup skb->cb, as qdisc layer will
++ overwrite it */
++ qdisc_enqueue_root(skb_shared, q); /* might kfree_skb */
++
++ if (likely(atomic_read(&skb_shared->users) == users + 1)) {
++ kfree_skb(skb_shared); /* decrease reference count by one */
++
++ skb->destructor = &imq_skb_destructor;
++
++ /* cloned? */
++ if (skb_orig)
++ kfree_skb(skb_orig); /* free original */
++
++ spin_unlock_bh(qdisc_lock(q));
++
++ /* schedule qdisc dequeue */
++ __netif_schedule(q);
++
++ retval = 0;
++ goto out;
++ } else {
++ skb_restore_cb(skb_shared); /* restore skb->cb */
++ skb->nf_queue_entry = NULL;
++ /* qdisc dropped packet and decreased skb reference count of
++ * skb, so we don't really want to and try refree as that would
++ * actually destroy the skb. */
++ spin_unlock_bh(qdisc_lock(q));
++ goto packet_not_eaten_by_imq_dev;
++ }
++
++packet_not_eaten_by_imq_dev:
++ /* cloned? restore original */
++ if (skb_orig) {
++ kfree_skb(skb);
++ entry->skb = skb_orig;
++ }
++ retval = -1;
++out:
++ return retval;
++}
++
++static struct nf_queue_handler nfqh = {
++ .name = "imq",
++ .outfn = imq_nf_queue,
++};
++
++static unsigned int imq_nf_hook(unsigned int hook, struct sk_buff *pskb,
++ const struct net_device *indev,
++ const struct net_device *outdev,
++ int (*okfn)(struct sk_buff *))
++{
++ if (pskb->imq_flags & IMQ_F_ENQUEUE)
++ return NF_QUEUE;
++
++ return NF_ACCEPT;
++}
++
++static int imq_close(struct net_device *dev)
++{
++ netif_stop_queue(dev);
++ return 0;
++}
++
++static int imq_open(struct net_device *dev)
++{
++ netif_start_queue(dev);
++ return 0;
++}
++
++static const struct net_device_ops imq_netdev_ops = {
++ .ndo_open = imq_open,
++ .ndo_stop = imq_close,
++ .ndo_start_xmit = imq_dev_xmit,
++ .ndo_get_stats = imq_get_stats,
++};
++
++static void imq_setup(struct net_device *dev)
++{
++ dev->netdev_ops = &imq_netdev_ops;
++ dev->type = ARPHRD_VOID;
++ dev->mtu = 16000;
++ dev->tx_queue_len = 11000;
++ dev->flags = IFF_NOARP;
++ dev->features = NETIF_F_SG | NETIF_F_FRAGLIST |
++ NETIF_F_GSO | NETIF_F_HW_CSUM |
++ NETIF_F_HIGHDMA;
++ dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
++}
++
++static int imq_validate(struct nlattr *tb[], struct nlattr *data[])
++{
++ int ret = 0;
++
++ if (tb[IFLA_ADDRESS]) {
++ if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) {
++ ret = -EINVAL;
++ goto end;
++ }
++ if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) {
++ ret = -EADDRNOTAVAIL;
++ goto end;
++ }
++ }
++ return 0;
++end:
++ printk(KERN_WARNING "IMQ: imq_validate failed (%d)\n", ret);
++ return ret;
++}
++
++static struct rtnl_link_ops imq_link_ops __read_mostly = {
++ .kind = "imq",
++ .priv_size = 0,
++ .setup = imq_setup,
++ .validate = imq_validate,
++};
++
++static int __init imq_init_hooks(void)
++{
++ int err;
++
++ nf_register_queue_imq_handler(&nfqh);
++
++ err = nf_register_hook(&imq_ingress_ipv4);
++ if (err)
++ goto err1;
++
++ err = nf_register_hook(&imq_egress_ipv4);
++ if (err)
++ goto err2;
++
++#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
++ err = nf_register_hook(&imq_ingress_ipv6);
++ if (err)
++ goto err3;
++
++ err = nf_register_hook(&imq_egress_ipv6);
++ if (err)
++ goto err4;
++#endif
++
++ return 0;
++
++#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
++err4:
++ nf_unregister_hook(&imq_ingress_ipv6);
++err3:
++ nf_unregister_hook(&imq_egress_ipv4);
++#endif
++err2:
++ nf_unregister_hook(&imq_ingress_ipv4);
++err1:
++ nf_unregister_queue_imq_handler();
++ return err;
++}
++
++static int __init imq_init_one(int index)
++{
++ struct net_device *dev;
++ int ret;
++
++ dev = alloc_netdev(0, "imq%d", imq_setup);
++ if (!dev)
++ return -ENOMEM;
++
++ ret = dev_alloc_name(dev, dev->name);
++ if (ret < 0)
++ goto fail;
++
++ dev->rtnl_link_ops = &imq_link_ops;
++ ret = register_netdevice(dev);
++ if (ret < 0)
++ goto fail;
++
++ return 0;
++fail:
++ free_netdev(dev);
++ return ret;
++}
++
++static int __init imq_init_devs(void)
++{
++ int err, i;
++
++ if (numdevs < 1 || numdevs > IMQ_MAX_DEVS) {
++ printk(KERN_ERR "IMQ: numdevs has to be betweed 1 and %u\n",
++ IMQ_MAX_DEVS);
++ return -EINVAL;
++ }
++
++ rtnl_lock();
++ err = __rtnl_link_register(&imq_link_ops);
++
++ for (i = 0; i < numdevs && !err; i++)
++ err = imq_init_one(i);
++
++ if (err) {
++ __rtnl_link_unregister(&imq_link_ops);
++ memset(imq_devs_cache, 0, sizeof(imq_devs_cache));
++ }
++ rtnl_unlock();
++
++ return err;
++}
++
++static int __init imq_init_module(void)
++{
++ int err;
++
++#if defined(CONFIG_IMQ_NUM_DEVS)
++ BUILD_BUG_ON(CONFIG_IMQ_NUM_DEVS > 16);
++ BUILD_BUG_ON(CONFIG_IMQ_NUM_DEVS < 2);
++ BUILD_BUG_ON(CONFIG_IMQ_NUM_DEVS - 1 > IMQ_F_IFMASK);
++#endif
++
++ err = imq_init_devs();
++ if (err) {
++ printk(KERN_ERR "IMQ: Error trying imq_init_devs(net)\n");
++ return err;
++ }
++
++ err = imq_init_hooks();
++ if (err) {
++ printk(KERN_ERR "IMQ: Error trying imq_init_hooks()\n");
++ rtnl_link_unregister(&imq_link_ops);
++ memset(imq_devs_cache, 0, sizeof(imq_devs_cache));
++ return err;
++ }
++
++ printk(KERN_INFO "IMQ driver loaded successfully.\n");
++
++#if defined(CONFIG_IMQ_BEHAVIOR_BA) || defined(CONFIG_IMQ_BEHAVIOR_BB)
++ printk(KERN_INFO "\tHooking IMQ before NAT on PREROUTING.\n");
++#else
++ printk(KERN_INFO "\tHooking IMQ after NAT on PREROUTING.\n");
++#endif
++#if defined(CONFIG_IMQ_BEHAVIOR_AB) || defined(CONFIG_IMQ_BEHAVIOR_BB)
++ printk(KERN_INFO "\tHooking IMQ before NAT on POSTROUTING.\n");
++#else
++ printk(KERN_INFO "\tHooking IMQ after NAT on POSTROUTING.\n");
++#endif
++
++ return 0;
++}
++
++static void __exit imq_unhook(void)
++{
++#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
++ nf_unregister_hook(&imq_ingress_ipv6);
++ nf_unregister_hook(&imq_egress_ipv6);
++#endif
++ nf_unregister_hook(&imq_ingress_ipv4);
++ nf_unregister_hook(&imq_egress_ipv4);
++
++ nf_unregister_queue_imq_handler();
++}
++
++static void __exit imq_cleanup_devs(void)
++{
++ rtnl_link_unregister(&imq_link_ops);
++ memset(imq_devs_cache, 0, sizeof(imq_devs_cache));
++}
++
++static void __exit imq_exit_module(void)
++{
++ imq_unhook();
++ imq_cleanup_devs();
++ printk(KERN_INFO "IMQ driver unloaded successfully.\n");
++}
++
++module_init(imq_init_module);
++module_exit(imq_exit_module);
++
++module_param(numdevs, int, 0);
++MODULE_PARM_DESC(numdevs, "number of IMQ devices (how many imq* devices will "
++ "be created)");
++MODULE_AUTHOR("http://www.linuximq.net");
++MODULE_DESCRIPTION("Pseudo-driver for the intermediate queue device. See "
++ "http://www.linuximq.net/ for more information.");
++MODULE_LICENSE("GPL");
++MODULE_ALIAS_RTNL_LINK("imq");
++
+--- a/drivers/net/Kconfig
++++ b/drivers/net/Kconfig
+@@ -124,6 +124,129 @@ config EQUALIZER
+ To compile this driver as a module, choose M here: the module
+ will be called eql. If unsure, say N.
+
++config IMQ
++ tristate "IMQ (intermediate queueing device) support"
++ depends on NETDEVICES && NETFILTER
++ ---help---
++ The IMQ device(s) is used as placeholder for QoS queueing
++ disciplines. Every packet entering/leaving the IP stack can be
++ directed through the IMQ device where it's enqueued/dequeued to the
++ attached qdisc. This allows you to treat network devices as classes
++ and distribute bandwidth among them. Iptables is used to specify
++ through which IMQ device, if any, packets travel.
++
++ More information at: http://www.linuximq.net/
++
++ To compile this driver as a module, choose M here: the module
++ will be called imq. If unsure, say N.
++
++choice
++ prompt "IMQ behavior (PRE/POSTROUTING)"
++ depends on IMQ
++ default IMQ_BEHAVIOR_AB
++ help
++
++ This settings defines how IMQ behaves in respect to its
++ hooking in PREROUTING and POSTROUTING.
++
++ IMQ can work in any of the following ways:
++
++ PREROUTING | POSTROUTING
++ -----------------|-------------------
++ #1 After NAT | After NAT
++ #2 After NAT | Before NAT
++ #3 Before NAT | After NAT
++ #4 Before NAT | Before NAT
++
++ The default behavior is to hook before NAT on PREROUTING
++ and after NAT on POSTROUTING (#3).
++
++ This settings are specially usefull when trying to use IMQ
++ to shape NATed clients.
++
++ More information can be found at: www.linuximq.net
++
++ If not sure leave the default settings alone.
++
++config IMQ_BEHAVIOR_AA
++ bool "IMQ AA"
++ help
++ This settings defines how IMQ behaves in respect to its
++ hooking in PREROUTING and POSTROUTING.
++
++ Choosing this option will make IMQ hook like this:
++
++ PREROUTING: After NAT
++ POSTROUTING: After NAT
++
++ More information can be found at: www.linuximq.net
++
++ If not sure leave the default settings alone.
++
++config IMQ_BEHAVIOR_AB
++ bool "IMQ AB"
++ help
++ This settings defines how IMQ behaves in respect to its
++ hooking in PREROUTING and POSTROUTING.
++
++ Choosing this option will make IMQ hook like this:
++
++ PREROUTING: After NAT
++ POSTROUTING: Before NAT
++
++ More information can be found at: www.linuximq.net
++
++ If not sure leave the default settings alone.
++
++config IMQ_BEHAVIOR_BA
++ bool "IMQ BA"
++ help
++ This settings defines how IMQ behaves in respect to its
++ hooking in PREROUTING and POSTROUTING.
++
++ Choosing this option will make IMQ hook like this:
++
++ PREROUTING: Before NAT
++ POSTROUTING: After NAT
++
++ More information can be found at: www.linuximq.net
++
++ If not sure leave the default settings alone.
++
++config IMQ_BEHAVIOR_BB
++ bool "IMQ BB"
++ help
++ This settings defines how IMQ behaves in respect to its
++ hooking in PREROUTING and POSTROUTING.
++
++ Choosing this option will make IMQ hook like this:
++
++ PREROUTING: Before NAT
++ POSTROUTING: Before NAT
++
++ More information can be found at: www.linuximq.net
++
++ If not sure leave the default settings alone.
++
++endchoice
++
++config IMQ_NUM_DEVS
++
++ int "Number of IMQ devices"
++ range 2 16
++ depends on IMQ
++ default "16"
++ help
++
++ This settings defines how many IMQ devices will be
++ created.
++
++ The default value is 16.
++
++ More information can be found at: www.linuximq.net
++
++ If not sure leave the default settings alone.
++
+ config TUN
+ tristate "Universal TUN/TAP device driver support"
+ select CRC32
+--- a/drivers/net/Makefile
++++ b/drivers/net/Makefile
+@@ -173,6 +173,7 @@ obj-$(CONFIG_SLHC) += slhc.o
+ obj-$(CONFIG_XEN_NETDEV_FRONTEND) += xen-netfront.o
+
+ obj-$(CONFIG_DUMMY) += dummy.o
++obj-$(CONFIG_IMQ) += imq.o
+ obj-$(CONFIG_IFB) += ifb.o
+ obj-$(CONFIG_MACVLAN) += macvlan.o
+ obj-$(CONFIG_MACVTAP) += macvtap.o
+--- /dev/null
++++ b/include/linux/imq.h
+@@ -0,0 +1,13 @@
++#ifndef _IMQ_H
++#define _IMQ_H
++
++/* IFMASK (16 device indexes, 0 to 15) and flag(s) fit in 5 bits */
++#define IMQ_F_BITS 5
++
++#define IMQ_F_IFMASK 0x0f
++#define IMQ_F_ENQUEUE 0x10
++
++#define IMQ_MAX_DEVS (IMQ_F_IFMASK + 1)
++
++#endif /* _IMQ_H */
++
+--- a/include/linux/netdevice.h
++++ b/include/linux/netdevice.h
+@@ -1323,6 +1323,7 @@ extern int dev_alloc_name(struct net_de
+ extern int dev_open(struct net_device *dev);
+ extern int dev_close(struct net_device *dev);
+ extern void dev_disable_lro(struct net_device *dev);
++extern struct netdev_queue *dev_pick_tx(struct net_device *dev, struct sk_buff *skb);
+ extern int dev_queue_xmit(struct sk_buff *skb);
+ extern int register_netdevice(struct net_device *dev);
+ extern void unregister_netdevice_queue(struct net_device *dev,
+--- /dev/null
++++ b/include/linux/netfilter/xt_IMQ.h
+@@ -0,0 +1,9 @@
++#ifndef _XT_IMQ_H
++#define _XT_IMQ_H
++
++struct xt_imq_info {
++ unsigned int todev; /* target imq device */
++};
++
++#endif /* _XT_IMQ_H */
++
+--- /dev/null
++++ b/include/linux/netfilter_ipv4/ipt_IMQ.h
+@@ -0,0 +1,10 @@
++#ifndef _IPT_IMQ_H
++#define _IPT_IMQ_H
++
++/* Backwards compatibility for old userspace */
++#include <linux/netfilter/xt_IMQ.h>
++
++#define ipt_imq_info xt_imq_info
++
++#endif /* _IPT_IMQ_H */
++
+--- /dev/null
++++ b/include/linux/netfilter_ipv6/ip6t_IMQ.h
+@@ -0,0 +1,10 @@
++#ifndef _IP6T_IMQ_H
++#define _IP6T_IMQ_H
++
++/* Backwards compatibility for old userspace */
++#include <linux/netfilter/xt_IMQ.h>
++
++#define ip6t_imq_info xt_imq_info
++
++#endif /* _IP6T_IMQ_H */
++
+--- a/include/linux/skbuff.h
++++ b/include/linux/skbuff.h
+@@ -29,6 +29,9 @@
+ #include <linux/rcupdate.h>
+ #include <linux/dmaengine.h>
+ #include <linux/hrtimer.h>
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++#include <linux/imq.h>
++#endif
+
+ /* Don't change this without changing skb_csum_unnecessary! */
+ #define CHECKSUM_NONE 0
+@@ -328,6 +331,9 @@ struct sk_buff {
+ * first. This is owned by whoever has the skb queued ATM.
+ */
+ char cb[48] __aligned(8);
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ void *cb_next;
++#endif
+
+ unsigned long _skb_refdst;
+ #ifdef CONFIG_XFRM
+@@ -364,6 +370,9 @@ struct sk_buff {
+ struct nf_conntrack *nfct;
+ struct sk_buff *nfct_reasm;
+ #endif
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ struct nf_queue_entry *nf_queue_entry;
++#endif
+ #ifdef CONFIG_BRIDGE_NETFILTER
+ struct nf_bridge_info *nf_bridge;
+ #endif
+@@ -390,6 +399,10 @@ struct sk_buff {
+
+ /* 0/14 bit hole */
+
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ __u8 imq_flags:IMQ_F_BITS;
++#endif
++
+ #ifdef CONFIG_NET_DMA
+ dma_cookie_t dma_cookie;
+ #endif
+@@ -476,6 +489,12 @@ static inline struct rtable *skb_rtable(
+ return (struct rtable *)skb_dst(skb);
+ }
+
++
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++extern int skb_save_cb(struct sk_buff *skb);
++extern int skb_restore_cb(struct sk_buff *skb);
++#endif
++
+ extern void kfree_skb(struct sk_buff *skb);
+ extern void consume_skb(struct sk_buff *skb);
+ extern void __kfree_skb(struct sk_buff *skb);
+@@ -2098,6 +2117,10 @@ static inline void __nf_copy(struct sk_b
+ dst->nfct_reasm = src->nfct_reasm;
+ nf_conntrack_get_reasm(src->nfct_reasm);
+ #endif
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ dst->imq_flags = src->imq_flags;
++ dst->nf_queue_entry = src->nf_queue_entry;
++#endif
+ #ifdef CONFIG_BRIDGE_NETFILTER
+ dst->nf_bridge = src->nf_bridge;
+ nf_bridge_get(src->nf_bridge);
+--- a/include/net/netfilter/nf_queue.h
++++ b/include/net/netfilter/nf_queue.h
+@@ -13,6 +13,12 @@ struct nf_queue_entry {
+ struct net_device *indev;
+ struct net_device *outdev;
+ int (*okfn)(struct sk_buff *);
++
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ int (*next_outfn)(struct nf_queue_entry *entry,
++ unsigned int queuenum);
++ unsigned int next_queuenum;
++#endif
+ };
+
+ #define nf_queue_entry_reroute(x) ((void *)x + sizeof(struct nf_queue_entry))
+@@ -30,5 +36,11 @@ extern int nf_unregister_queue_handler(u
+ const struct nf_queue_handler *qh);
+ extern void nf_unregister_queue_handlers(const struct nf_queue_handler *qh);
+ extern void nf_reinject(struct nf_queue_entry *entry, unsigned int verdict);
++extern void nf_queue_entry_release_refs(struct nf_queue_entry *entry);
++
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++extern void nf_register_queue_imq_handler(const struct nf_queue_handler *qh);
++extern void nf_unregister_queue_imq_handler(void);
++#endif
+
+ #endif /* _NF_QUEUE_H */
+--- a/net/core/dev.c
++++ b/net/core/dev.c
+@@ -98,6 +98,9 @@
+ #include <net/net_namespace.h>
+ #include <net/sock.h>
+ #include <linux/rtnetlink.h>
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++#include <linux/imq.h>
++#endif
+ #include <linux/proc_fs.h>
+ #include <linux/seq_file.h>
+ #include <linux/stat.h>
+@@ -1995,7 +1998,11 @@ int dev_hard_start_xmit(struct sk_buff *
+ int rc = NETDEV_TX_OK;
+
+ if (likely(!skb->next)) {
+- if (!list_empty(&ptype_all))
++ if (!list_empty(&ptype_all)
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ && !(skb->imq_flags & IMQ_F_ENQUEUE)
++#endif
++ )
+ dev_queue_xmit_nit(skb, dev);
+
+ /*
+@@ -2119,8 +2126,7 @@ static inline u16 dev_cap_txqueue(struct
+ return queue_index;
+ }
+
+-static struct netdev_queue *dev_pick_tx(struct net_device *dev,
+- struct sk_buff *skb)
++struct netdev_queue *dev_pick_tx(struct net_device *dev, struct sk_buff *skb)
+ {
+ int queue_index;
+ const struct net_device_ops *ops = dev->netdev_ops;
+@@ -2149,6 +2155,7 @@ static struct netdev_queue *dev_pick_tx(
+ skb_set_queue_mapping(skb, queue_index);
+ return netdev_get_tx_queue(dev, queue_index);
+ }
++EXPORT_SYMBOL(dev_pick_tx);
+
+ static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
+ struct net_device *dev,
+--- a/net/core/skbuff.c
++++ b/net/core/skbuff.c
+@@ -72,6 +72,9 @@
+
+ static struct kmem_cache *skbuff_head_cache __read_mostly;
+ static struct kmem_cache *skbuff_fclone_cache __read_mostly;
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++static struct kmem_cache *skbuff_cb_store_cache __read_mostly;
++#endif
+
+ static void sock_pipe_buf_release(struct pipe_inode_info *pipe,
+ struct pipe_buffer *buf)
+@@ -91,6 +94,83 @@ static int sock_pipe_buf_steal(struct pi
+ return 1;
+ }
+
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++/* Control buffer save/restore for IMQ devices */
++struct skb_cb_table {
++ void *cb_next;
++ atomic_t refcnt;
++ char cb[48];
++};
++
++static DEFINE_SPINLOCK(skb_cb_store_lock);
++
++int skb_save_cb(struct sk_buff *skb)
++{
++ struct skb_cb_table *next;
++
++ next = kmem_cache_alloc(skbuff_cb_store_cache, GFP_ATOMIC);
++ if (!next)
++ return -ENOMEM;
++
++ BUILD_BUG_ON(sizeof(skb->cb) != sizeof(next->cb));
++
++ memcpy(next->cb, skb->cb, sizeof(skb->cb));
++ next->cb_next = skb->cb_next;
++
++ atomic_set(&next->refcnt, 1);
++
++ skb->cb_next = next;
++ return 0;
++}
++EXPORT_SYMBOL(skb_save_cb);
++
++int skb_restore_cb(struct sk_buff *skb)
++{
++ struct skb_cb_table *next;
++
++ if (!skb->cb_next)
++ return 0;
++
++ next = skb->cb_next;
++
++ BUILD_BUG_ON(sizeof(skb->cb) != sizeof(next->cb));
++
++ memcpy(skb->cb, next->cb, sizeof(skb->cb));
++ skb->cb_next = next->cb_next;
++
++ spin_lock(&skb_cb_store_lock);
++
++ if (atomic_dec_and_test(&next->refcnt)) {
++ kmem_cache_free(skbuff_cb_store_cache, next);
++ }
++
++ spin_unlock(&skb_cb_store_lock);
++
++ return 0;
++}
++EXPORT_SYMBOL(skb_restore_cb);
++
++static void skb_copy_stored_cb(struct sk_buff *new, const struct sk_buff *__old)
++{
++ struct skb_cb_table *next;
++ struct sk_buff *old;
++
++ if (!__old->cb_next) {
++ new->cb_next = NULL;
++ return;
++ }
++
++ spin_lock(&skb_cb_store_lock);
++
++ old = (struct sk_buff *)__old;
++
++ next = old->cb_next;
++ atomic_inc(&next->refcnt);
++ new->cb_next = next;
++
++ spin_unlock(&skb_cb_store_lock);
++}
++#endif
+
+ /* Pipe buffer operations for a socket. */
+ static const struct pipe_buf_operations sock_pipe_buf_ops = {
+@@ -378,6 +458,26 @@ static void skb_release_head_state(struc
+ WARN_ON(in_irq());
+ skb->destructor(skb);
+ }
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ /* This should not happen. When it does, avoid memleak by restoring
++ the chain of cb-backups. */
++ while(skb->cb_next != NULL) {
++ if (net_ratelimit())
++ printk(KERN_WARNING "IMQ: kfree_skb: skb->cb_next: "
++ "%08x\n", (unsigned int)skb->cb_next);
++
++ skb_restore_cb(skb);
++ }
++ /* This should not happen either, nf_queue_entry is nullified in
++ * imq_dev_xmit(). If we have non-NULL nf_queue_entry then we are
++ * leaking entry pointers, maybe memory. We don't know if this is
++ * pointer to already freed memory, or should this be freed.
++ * If this happens we need to add refcounting, etc for nf_queue_entry.
++ */
++ if (skb->nf_queue_entry && net_ratelimit())
++ printk(KERN_WARNING
++ "IMQ: kfree_skb: skb->nf_queue_entry != NULL");
++#endif
+ #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
+ nf_conntrack_put(skb->nfct);
+ nf_conntrack_put_reasm(skb->nfct_reasm);
+@@ -514,6 +614,9 @@ static void __copy_skb_header(struct sk_
+ new->sp = secpath_get(old->sp);
+ #endif
+ memcpy(new->cb, old->cb, sizeof(old->cb));
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ skb_copy_stored_cb(new, old);
++#endif
+ new->csum = old->csum;
+ new->local_df = old->local_df;
+ new->pkt_type = old->pkt_type;
+@@ -2765,6 +2868,13 @@ void __init skb_init(void)
+ 0,
+ SLAB_HWCACHE_ALIGN|SLAB_PANIC,
+ NULL);
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ skbuff_cb_store_cache = kmem_cache_create("skbuff_cb_store_cache",
++ sizeof(struct skb_cb_table),
++ 0,
++ SLAB_HWCACHE_ALIGN|SLAB_PANIC,
++ NULL);
++#endif
+ }
+
+ /**
+--- a/net/netfilter/Kconfig
++++ b/net/netfilter/Kconfig
+@@ -455,6 +455,18 @@ config NETFILTER_XT_TARGET_LED
+ For more information on the LEDs available on your system, see
+ Documentation/leds-class.txt
+
++config NETFILTER_XT_TARGET_IMQ
++ tristate '"IMQ" target support'
++ depends on NETFILTER_XTABLES
++ depends on IP_NF_MANGLE || IP6_NF_MANGLE
++ select IMQ
++ default m if NETFILTER_ADVANCED=n
++ help
++ This option adds a `IMQ' target which is used to specify if and
++ to which imq device packets should get enqueued/dequeued.
++
++ To compile it as a module, choose M here. If unsure, say N.
++
+ config NETFILTER_XT_TARGET_MARK
+ tristate '"MARK" target support'
+ depends on NETFILTER_ADVANCED
+--- a/net/netfilter/Makefile
++++ b/net/netfilter/Makefile
+@@ -51,6 +51,7 @@ obj-$(CONFIG_NETFILTER_XT_TARGET_CONNSEC
+ obj-$(CONFIG_NETFILTER_XT_TARGET_CT) += xt_CT.o
+ obj-$(CONFIG_NETFILTER_XT_TARGET_DSCP) += xt_DSCP.o
+ obj-$(CONFIG_NETFILTER_XT_TARGET_HL) += xt_HL.o
++obj-$(CONFIG_NETFILTER_XT_TARGET_IMQ) += xt_IMQ.o
+ obj-$(CONFIG_NETFILTER_XT_TARGET_LED) += xt_LED.o
+ obj-$(CONFIG_NETFILTER_XT_TARGET_NFLOG) += xt_NFLOG.o
+ obj-$(CONFIG_NETFILTER_XT_TARGET_NFQUEUE) += xt_NFQUEUE.o
+--- a/net/netfilter/nf_queue.c
++++ b/net/netfilter/nf_queue.c
+@@ -22,6 +22,26 @@ static const struct nf_queue_handler __r
+
+ static DEFINE_MUTEX(queue_handler_mutex);
+
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++static const struct nf_queue_handler *queue_imq_handler;
++
++void nf_register_queue_imq_handler(const struct nf_queue_handler *qh)
++{
++ mutex_lock(&queue_handler_mutex);
++ rcu_assign_pointer(queue_imq_handler, qh);
++ mutex_unlock(&queue_handler_mutex);
++}
++EXPORT_SYMBOL(nf_register_queue_imq_handler);
++
++void nf_unregister_queue_imq_handler(void)
++{
++ mutex_lock(&queue_handler_mutex);
++ rcu_assign_pointer(queue_imq_handler, NULL);
++ mutex_unlock(&queue_handler_mutex);
++}
++EXPORT_SYMBOL(nf_unregister_queue_imq_handler);
++#endif
++
+ /* return EBUSY when somebody else is registered, return EEXIST if the
+ * same handler is registered, return 0 in case of success. */
+ int nf_register_queue_handler(u_int8_t pf, const struct nf_queue_handler *qh)
+@@ -82,7 +102,7 @@ void nf_unregister_queue_handlers(const
+ }
+ EXPORT_SYMBOL_GPL(nf_unregister_queue_handlers);
+
+-static void nf_queue_entry_release_refs(struct nf_queue_entry *entry)
++void nf_queue_entry_release_refs(struct nf_queue_entry *entry)
+ {
+ /* Release those devices we held, or Alexey will kill me. */
+ if (entry->indev)
+@@ -102,6 +122,7 @@ static void nf_queue_entry_release_refs(
+ /* Drop reference to owner of hook which queued us. */
+ module_put(entry->elem->owner);
+ }
++EXPORT_SYMBOL_GPL(nf_queue_entry_release_refs);
+
+ /*
+ * Any packet that leaves via this function must come back
+@@ -123,12 +144,26 @@ static int __nf_queue(struct sk_buff *sk
+ #endif
+ const struct nf_afinfo *afinfo;
+ const struct nf_queue_handler *qh;
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ const struct nf_queue_handler *qih = NULL;
++#endif
+
+ /* QUEUE == DROP if noone is waiting, to be safe. */
+ rcu_read_lock();
+
+ qh = rcu_dereference(queue_handler[pf]);
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
++ if (pf == PF_INET || pf == PF_INET6)
++#else
++ if (pf == PF_INET)
++#endif
++ qih = rcu_dereference(queue_imq_handler);
++
++ if (!qh && !qih)
++#else /* !IMQ */
+ if (!qh)
++#endif
+ goto err_unlock;
+
+ afinfo = nf_get_afinfo(pf);
+@@ -147,6 +182,10 @@ static int __nf_queue(struct sk_buff *sk
+ .indev = indev,
+ .outdev = outdev,
+ .okfn = okfn,
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ .next_outfn = qh ? qh->outfn : NULL,
++ .next_queuenum = queuenum,
++#endif
+ };
+
+ /* If it's going away, ignore hook. */
+@@ -173,8 +212,19 @@ static int __nf_queue(struct sk_buff *sk
+ #endif
+ skb_dst_force(skb);
+ afinfo->saveroute(skb, entry);
++
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++ if (qih) {
++ status = qih->outfn(entry, queuenum);
++ goto imq_skip_queue;
++ }
++#endif
++
+ status = qh->outfn(entry, queuenum);
+
++#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
++imq_skip_queue:
++#endif
+ rcu_read_unlock();
+
+ if (status < 0) {
+--- /dev/null
++++ b/net/netfilter/xt_IMQ.c
+@@ -0,0 +1,73 @@
++/*
++ * This target marks packets to be enqueued to an imq device
++ */
++#include <linux/module.h>
++#include <linux/skbuff.h>
++#include <linux/netfilter/x_tables.h>
++#include <linux/netfilter/xt_IMQ.h>
++#include <linux/imq.h>
++
++static unsigned int imq_target(struct sk_buff *pskb,
++ const struct xt_action_param *par)
++{
++ const struct xt_imq_info *mr = par->targinfo;
++
++ pskb->imq_flags = (mr->todev & IMQ_F_IFMASK) | IMQ_F_ENQUEUE;
++
++ return XT_CONTINUE;
++}
++
++static int imq_checkentry(const struct xt_tgchk_param *par)
++{
++ struct xt_imq_info *mr = par->targinfo;
++
++ if (mr->todev > IMQ_MAX_DEVS - 1) {
++ printk(KERN_WARNING
++ "IMQ: invalid device specified, highest is %u\n",
++ IMQ_MAX_DEVS - 1);
++ return -EINVAL;
++ }
++
++ return 0;
++}
++
++static struct xt_target xt_imq_reg[] __read_mostly = {
++ {
++ .name = "IMQ",
++ .family = AF_INET,
++ .checkentry = imq_checkentry,
++ .target = imq_target,
++ .targetsize = sizeof(struct xt_imq_info),
++ .table = "mangle",
++ .me = THIS_MODULE
++ },
++ {
++ .name = "IMQ",
++ .family = AF_INET6,
++ .checkentry = imq_checkentry,
++ .target = imq_target,
++ .targetsize = sizeof(struct xt_imq_info),
++ .table = "mangle",
++ .me = THIS_MODULE
++ },
++};
++
++static int __init imq_init(void)
++{
++ return xt_register_targets(xt_imq_reg, ARRAY_SIZE(xt_imq_reg));
++}
++
++static void __exit imq_fini(void)
++{
++ xt_unregister_targets(xt_imq_reg, ARRAY_SIZE(xt_imq_reg));
++}
++
++module_init(imq_init);
++module_exit(imq_fini);
++
++MODULE_AUTHOR("http://www.linuximq.net");
++MODULE_DESCRIPTION("Pseudo-driver for the intermediate queue device. See http://www.linuximq.net/ for more information.");
++MODULE_LICENSE("GPL");
++MODULE_ALIAS("ipt_IMQ");
++MODULE_ALIAS("ip6t_IMQ");
++
projects / openwrt / staging / yousong.git / commitdiff