kernel-imq.patch

   1 diff -uNr linux-2.6.34/drivers/net/imq.c linux-2.6.34-imq/drivers/net/imq.c
   2 --- linux-2.6.34/drivers/net/imq.c      1970-01-01 02:00:00.000000000 +0200
   3 +++ linux-2.6.34-imq/drivers/net/imq.c  2010-06-02 10:05:45.752109073 +0300
   4 @@ -0,0 +1,635 @@
   5 +/*
   6 + *             Pseudo-driver for the intermediate queue device.
   7 + *
   8 + *             This program is free software; you can redistribute it and/or
   9 + *             modify it under the terms of the GNU General Public License
  10 + *             as published by the Free Software Foundation; either version
  11 + *             2 of the License, or (at your option) any later version.
  12 + *
  13 + * Authors:    Patrick McHardy, <kaber@trash.net>
  14 + *
  15 + *            The first version was written by Martin Devera, <devik@cdi.cz>
  16 + *
  17 + * Credits:    Jan Rafaj <imq2t@cedric.vabo.cz>
  18 + *              - Update patch to 2.4.21
  19 + *             Sebastian Strollo <sstrollo@nortelnetworks.com>
  20 + *              - Fix "Dead-loop on netdevice imq"-issue
  21 + *             Marcel Sebek <sebek64@post.cz>
  22 + *              - Update to 2.6.2-rc1
  23 + *
  24 + *            After some time of inactivity there is a group taking care
  25 + *            of IMQ again: http://www.linuximq.net
  26 + *
  27 + *
  28 + *            2004/06/30 - New version of IMQ patch to kernels <=2.6.7
  29 + *             including the following changes:
  30 + *
  31 + *            - Correction of ipv6 support "+"s issue (Hasso Tepper)
  32 + *            - Correction of imq_init_devs() issue that resulted in
  33 + *            kernel OOPS unloading IMQ as module (Norbert Buchmuller)
  34 + *            - Addition of functionality to choose number of IMQ devices
  35 + *            during kernel config (Andre Correa)
  36 + *            - Addition of functionality to choose how IMQ hooks on
  37 + *            PRE and POSTROUTING (after or before NAT) (Andre Correa)
  38 + *            - Cosmetic corrections (Norbert Buchmuller) (Andre Correa)
  39 + *
  40 + *
  41 + *             2005/12/16 - IMQ versions between 2.6.7 and 2.6.13 were
  42 + *             released with almost no problems. 2.6.14-x was released
  43 + *             with some important changes: nfcache was removed; After
  44 + *             some weeks of trouble we figured out that some IMQ fields
  45 + *             in skb were missing in skbuff.c - skb_clone and copy_skb_header.
  46 + *             These functions are correctly patched by this new patch version.
  47 + *
  48 + *             Thanks for all who helped to figure out all the problems with
  49 + *             2.6.14.x: Patrick McHardy, Rune Kock, VeNoMouS, Max CtRiX,
  50 + *             Kevin Shanahan, Richard Lucassen, Valery Dachev (hopefully
  51 + *             I didn't forget anybody). I apologize again for my lack of time.
  52 + *
  53 + *
  54 + *             2008/06/17 - 2.6.25 - Changed imq.c to use qdisc_run() instead
  55 + *             of qdisc_restart() and moved qdisc_run() to tasklet to avoid
  56 + *             recursive locking. New initialization routines to fix 'rmmod' not
  57 + *             working anymore. Used code from ifb.c. (Jussi Kivilinna)
  58 + *
  59 + *             2008/08/06 - 2.6.26 - (JK)
  60 + *              - Replaced tasklet with 'netif_schedule()'.
  61 + *              - Cleaned up and added comments for imq_nf_queue().
  62 + *
  63 + *             2009/04/12
  64 + *              - Add skb_save_cb/skb_restore_cb helper functions for backuping
  65 + *                control buffer. This is needed because qdisc-layer on kernels
  66 + *                2.6.27 and newer overwrite control buffer. (Jussi Kivilinna)
  67 + *              - Add better locking for IMQ device. Hopefully this will solve
  68 + *                SMP issues. (Jussi Kivilinna)
  69 + *              - Port to 2.6.27
  70 + *              - Port to 2.6.28
  71 + *              - Port to 2.6.29 + fix rmmod not working
  72 + *
  73 + *             2009/04/20 - (Jussi Kivilinna)
  74 + *              - Use netdevice feature flags to avoid extra packet handling
  75 + *                by core networking layer and possibly increase performance.
  76 + *
  77 + *             2009/09/26 - (Jussi Kivilinna)
  78 + *              - Add imq_nf_reinject_lockless to fix deadlock with
  79 + *                imq_nf_queue/imq_nf_reinject.
  80 + *
  81 + *             2009/12/08 - (Jussi Kivilinna)
  82 + *              - Port to 2.6.32
  83 + *              - Add check for skb->nf_queue_entry==NULL in imq_dev_xmit()
  84 + *              - Also add better error checking for skb->nf_queue_entry usage
  85 + *
  86 + *             2010/02/25 - (Jussi Kivilinna)
  87 + *              - Port to 2.6.33
  88 + *
  89 + *            Also, many thanks to pablo Sebastian Greco for making the initial
  90 + *            patch and to those who helped the testing.
  91 + *
  92 + *             More info at: http://www.linuximq.net/ (Andre Correa)
  93 + */
  94 +
  95 +#include <linux/module.h>
  96 +#include <linux/kernel.h>
  97 +#include <linux/moduleparam.h>
  98 +#include <linux/list.h>
  99 +#include <linux/skbuff.h>
 100 +#include <linux/netdevice.h>
 101 +#include <linux/etherdevice.h>
 102 +#include <linux/rtnetlink.h>
 103 +#include <linux/if_arp.h>
 104 +#include <linux/netfilter.h>
 105 +#include <linux/netfilter_ipv4.h>
 106 +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 107 +       #include <linux/netfilter_ipv6.h>
 108 +#endif
 109 +#include <linux/imq.h>
 110 +#include <net/pkt_sched.h>
 111 +#include <net/netfilter/nf_queue.h>
 112 +
 113 +static nf_hookfn imq_nf_hook;
 114 +
 115 +static struct nf_hook_ops imq_ingress_ipv4 = {
 116 +       .hook           = imq_nf_hook,
 117 +       .owner          = THIS_MODULE,
 118 +       .pf             = PF_INET,
 119 +       .hooknum        = NF_INET_PRE_ROUTING,
 120 +#if defined(CONFIG_IMQ_BEHAVIOR_BA) || defined(CONFIG_IMQ_BEHAVIOR_BB)
 121 +       .priority       = NF_IP_PRI_MANGLE + 1
 122 +#else
 123 +       .priority       = NF_IP_PRI_NAT_DST + 1
 124 +#endif
 125 +};
 126 +
 127 +static struct nf_hook_ops imq_egress_ipv4 = {
 128 +       .hook           = imq_nf_hook,
 129 +       .owner          = THIS_MODULE,
 130 +       .pf             = PF_INET,
 131 +       .hooknum        = NF_INET_POST_ROUTING,
 132 +#if defined(CONFIG_IMQ_BEHAVIOR_AA) || defined(CONFIG_IMQ_BEHAVIOR_BA)
 133 +       .priority       = NF_IP_PRI_LAST
 134 +#else
 135 +       .priority       = NF_IP_PRI_NAT_SRC - 1
 136 +#endif
 137 +};
 138 +
 139 +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 140 +static struct nf_hook_ops imq_ingress_ipv6 = {
 141 +       .hook           = imq_nf_hook,
 142 +       .owner          = THIS_MODULE,
 143 +       .pf             = PF_INET6,
 144 +       .hooknum        = NF_INET_PRE_ROUTING,
 145 +#if defined(CONFIG_IMQ_BEHAVIOR_BA) || defined(CONFIG_IMQ_BEHAVIOR_BB)
 146 +       .priority       = NF_IP6_PRI_MANGLE + 1
 147 +#else
 148 +       .priority       = NF_IP6_PRI_NAT_DST + 1
 149 +#endif
 150 +};
 151 +
 152 +static struct nf_hook_ops imq_egress_ipv6 = {
 153 +       .hook           = imq_nf_hook,
 154 +       .owner          = THIS_MODULE,
 155 +       .pf             = PF_INET6,
 156 +       .hooknum        = NF_INET_POST_ROUTING,
 157 +#if defined(CONFIG_IMQ_BEHAVIOR_AA) || defined(CONFIG_IMQ_BEHAVIOR_BA)
 158 +       .priority       = NF_IP6_PRI_LAST
 159 +#else
 160 +       .priority       = NF_IP6_PRI_NAT_SRC - 1
 161 +#endif
 162 +};
 163 +#endif
 164 +
 165 +#if defined(CONFIG_IMQ_NUM_DEVS)
 166 +static unsigned int numdevs = CONFIG_IMQ_NUM_DEVS;
 167 +#else
 168 +static unsigned int numdevs = IMQ_MAX_DEVS;
 169 +#endif
 170 +
 171 +static DEFINE_SPINLOCK(imq_nf_queue_lock);
 172 +
 173 +static struct net_device *imq_devs_cache[IMQ_MAX_DEVS];
 174 +
 175 +
 176 +static struct net_device_stats *imq_get_stats(struct net_device *dev)
 177 +{
 178 +       return &dev->stats;
 179 +}
 180 +
 181 +/* called for packets kfree'd in qdiscs at places other than enqueue */
 182 +static void imq_skb_destructor(struct sk_buff *skb)
 183 +{
 184 +       struct nf_queue_entry *entry = skb->nf_queue_entry;
 185 +
 186 +       skb->nf_queue_entry = NULL;
 187 +
 188 +       if (entry) {
 189 +               nf_queue_entry_release_refs(entry);
 190 +               kfree(entry);
 191 +       }
 192 +
 193 +       skb_restore_cb(skb); /* kfree backup */
 194 +}
 195 +
 196 +/* locking not needed when called from imq_nf_queue */
 197 +static void imq_nf_reinject_lockless(struct nf_queue_entry *entry,
 198 +                                               unsigned int verdict)
 199 +{
 200 +       int status;
 201 +
 202 +       if (!entry->next_outfn) {
 203 +               nf_reinject(entry, verdict);
 204 +               return;
 205 +       }
 206 +
 207 +       status = entry->next_outfn(entry, entry->next_queuenum);
 208 +       if (status < 0) {
 209 +               nf_queue_entry_release_refs(entry);
 210 +               kfree_skb(entry->skb);
 211 +               kfree(entry);
 212 +       }
 213 +}
 214 +
 215 +static void imq_nf_reinject(struct nf_queue_entry *entry, unsigned int verdict)
 216 +{
 217 +       int status;
 218 +
 219 +       if (!entry->next_outfn) {
 220 +               spin_lock_bh(&imq_nf_queue_lock);
 221 +               nf_reinject(entry, verdict);
 222 +               spin_unlock_bh(&imq_nf_queue_lock);
 223 +               return;
 224 +       }
 225 +
 226 +       rcu_read_lock();
 227 +       local_bh_disable();
 228 +       status = entry->next_outfn(entry, entry->next_queuenum);
 229 +       local_bh_enable();
 230 +       if (status < 0) {
 231 +               nf_queue_entry_release_refs(entry);
 232 +               kfree_skb(entry->skb);
 233 +               kfree(entry);
 234 +       }
 235 +
 236 +       rcu_read_unlock();
 237 +}
 238 +
 239 +static netdev_tx_t imq_dev_xmit(struct sk_buff *skb, struct net_device *dev)
 240 +{
 241 +       struct nf_queue_entry *entry = skb->nf_queue_entry;
 242 +
 243 +       skb->nf_queue_entry = NULL;
 244 +       dev->trans_start = jiffies;
 245 +
 246 +       dev->stats.tx_bytes += skb->len;
 247 +       dev->stats.tx_packets++;
 248 +
 249 +       if (entry == NULL) {
 250 +               /* We don't know what is going on here.. packet is queued for
 251 +                * imq device, but (probably) not by us.
 252 +                *
 253 +                * If this packet was not send here by imq_nf_queue(), then
 254 +                * skb_save_cb() was not used and skb_free() should not show:
 255 +                *   WARNING: IMQ: kfree_skb: skb->cb_next:..
 256 +                * and/or
 257 +                *   WARNING: IMQ: kfree_skb: skb->nf_queue_entry...
 258 +                *
 259 +                * However if this message is shown, then IMQ is somehow broken
 260 +                * and you should report this to linuximq.net.
 261 +                */
 262 +
 263 +               /* imq_dev_xmit is black hole that eats all packets, report that
 264 +                * we eat this packet happily and increase dropped counters.
 265 +                */
 266 +
 267 +               dev->stats.tx_dropped++;
 268 +               dev_kfree_skb(skb);
 269 +
 270 +               return NETDEV_TX_OK;
 271 +       }
 272 +
 273 +       skb_restore_cb(skb); /* restore skb->cb */
 274 +
 275 +       skb->imq_flags = 0;
 276 +       skb->destructor = NULL;
 277 +
 278 +       imq_nf_reinject(entry, NF_ACCEPT);
 279 +
 280 +       return NETDEV_TX_OK;
 281 +}
 282 +
 283 +static int imq_nf_queue(struct nf_queue_entry *entry, unsigned queue_num)
 284 +{
 285 +       struct net_device *dev;
 286 +       struct sk_buff *skb_orig, *skb, *skb_shared;
 287 +       struct Qdisc *q;
 288 +       struct netdev_queue *txq;
 289 +       int users, index;
 290 +       int retval = -EINVAL;
 291 +
 292 +       index = entry->skb->imq_flags & IMQ_F_IFMASK;
 293 +       if (unlikely(index > numdevs - 1)) {
 294 +               if (net_ratelimit())
 295 +                       printk(KERN_WARNING
 296 +                              "IMQ: invalid device specified, highest is %u\n",
 297 +                              numdevs - 1);
 298 +               retval = -EINVAL;
 299 +               goto out;
 300 +       }
 301 +
 302 +       /* check for imq device by index from cache */
 303 +       dev = imq_devs_cache[index];
 304 +       if (unlikely(!dev)) {
 305 +               char buf[8];
 306 +
 307 +               /* get device by name and cache result */
 308 +               snprintf(buf, sizeof(buf), "imq%d", index);
 309 +               dev = dev_get_by_name(&init_net, buf);
 310 +               if (!dev) {
 311 +                       /* not found ?!*/
 312 +                       BUG();
 313 +                       retval = -ENODEV;
 314 +                       goto out;
 315 +               }
 316 +
 317 +               imq_devs_cache[index] = dev;
 318 +               dev_put(dev);
 319 +       }
 320 +
 321 +       if (unlikely(!(dev->flags & IFF_UP))) {
 322 +               entry->skb->imq_flags = 0;
 323 +               imq_nf_reinject_lockless(entry, NF_ACCEPT);
 324 +               retval = 0;
 325 +               goto out;
 326 +       }
 327 +       dev->last_rx = jiffies;
 328 +
 329 +       skb = entry->skb;
 330 +       skb_orig = NULL;
 331 +
 332 +       /* skb has owner? => make clone */
 333 +       if (unlikely(skb->destructor)) {
 334 +               skb_orig = skb;
 335 +               skb = skb_clone(skb, GFP_ATOMIC);
 336 +               if (!skb) {
 337 +                       retval = -ENOMEM;
 338 +                       goto out;
 339 +               }
 340 +               entry->skb = skb;
 341 +       }
 342 +
 343 +       skb->nf_queue_entry = entry;
 344 +
 345 +       dev->stats.rx_bytes += skb->len;
 346 +       dev->stats.rx_packets++;
 347 +
 348 +       txq = dev_pick_tx(dev, skb);
 349 +
 350 +       q = rcu_dereference(txq->qdisc);
 351 +       if (unlikely(!q->enqueue))
 352 +               goto packet_not_eaten_by_imq_dev;
 353 +
 354 +       spin_lock_bh(qdisc_lock(q));
 355 +
 356 +       users = atomic_read(&skb->users);
 357 +
 358 +       skb_shared = skb_get(skb); /* increase reference count by one */
 359 +       skb_save_cb(skb_shared); /* backup skb->cb, as qdisc layer will
 360 +                                       overwrite it */
 361 +       qdisc_enqueue_root(skb_shared, q); /* might kfree_skb */
 362 +
 363 +       if (likely(atomic_read(&skb_shared->users) == users + 1)) {
 364 +               kfree_skb(skb_shared); /* decrease reference count by one */
 365 +
 366 +               skb->destructor = &imq_skb_destructor;
 367 +
 368 +               /* cloned? */
 369 +               if (skb_orig)
 370 +                       kfree_skb(skb_orig); /* free original */
 371 +
 372 +               spin_unlock_bh(qdisc_lock(q));
 373 +
 374 +               /* schedule qdisc dequeue */
 375 +               __netif_schedule(q);
 376 +
 377 +               retval = 0;
 378 +               goto out;
 379 +       } else {
 380 +               skb_restore_cb(skb_shared); /* restore skb->cb */
 381 +               skb->nf_queue_entry = NULL;
 382 +               /* qdisc dropped packet and decreased skb reference count of
 383 +                * skb, so we don't really want to and try refree as that would
 384 +                * actually destroy the skb. */
 385 +               spin_unlock_bh(qdisc_lock(q));
 386 +               goto packet_not_eaten_by_imq_dev;
 387 +       }
 388 +
 389 +packet_not_eaten_by_imq_dev:
 390 +       /* cloned? restore original */
 391 +       if (skb_orig) {
 392 +               kfree_skb(skb);
 393 +               entry->skb = skb_orig;
 394 +       }
 395 +       retval = -1;
 396 +out:
 397 +       return retval;
 398 +}
 399 +
 400 +static struct nf_queue_handler nfqh = {
 401 +       .name  = "imq",
 402 +       .outfn = imq_nf_queue,
 403 +};
 404 +
 405 +static unsigned int imq_nf_hook(unsigned int hook, struct sk_buff *pskb,
 406 +                               const struct net_device *indev,
 407 +                               const struct net_device *outdev,
 408 +                               int (*okfn)(struct sk_buff *))
 409 +{
 410 +       if (pskb->imq_flags & IMQ_F_ENQUEUE)
 411 +               return NF_QUEUE;
 412 +
 413 +       return NF_ACCEPT;
 414 +}
 415 +
 416 +static int imq_close(struct net_device *dev)
 417 +{
 418 +       netif_stop_queue(dev);
 419 +       return 0;
 420 +}
 421 +
 422 +static int imq_open(struct net_device *dev)
 423 +{
 424 +       netif_start_queue(dev);
 425 +       return 0;
 426 +}
 427 +
 428 +static const struct net_device_ops imq_netdev_ops = {
 429 +       .ndo_open               = imq_open,
 430 +       .ndo_stop               = imq_close,
 431 +       .ndo_start_xmit         = imq_dev_xmit,
 432 +       .ndo_get_stats          = imq_get_stats,
 433 +};
 434 +
 435 +static void imq_setup(struct net_device *dev)
 436 +{
 437 +       dev->netdev_ops         = &imq_netdev_ops;
 438 +       dev->type               = ARPHRD_VOID;
 439 +       dev->mtu                = 16000;
 440 +       dev->tx_queue_len       = 11000;
 441 +       dev->flags              = IFF_NOARP;
 442 +       dev->features           = NETIF_F_SG | NETIF_F_FRAGLIST |
 443 +                                 NETIF_F_GSO | NETIF_F_HW_CSUM |
 444 +                                 NETIF_F_HIGHDMA;
 445 +       dev->priv_flags         &= ~IFF_XMIT_DST_RELEASE;
 446 +}
 447 +
 448 +static int imq_validate(struct nlattr *tb[], struct nlattr *data[])
 449 +{
 450 +       int ret = 0;
 451 +
 452 +       if (tb[IFLA_ADDRESS]) {
 453 +               if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) {
 454 +                       ret = -EINVAL;
 455 +                       goto end;
 456 +               }
 457 +               if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) {
 458 +                       ret = -EADDRNOTAVAIL;
 459 +                       goto end;
 460 +               }
 461 +       }
 462 +       return 0;
 463 +end:
 464 +       printk(KERN_WARNING "IMQ: imq_validate failed (%d)\n", ret);
 465 +       return ret;
 466 +}
 467 +
 468 +static struct rtnl_link_ops imq_link_ops __read_mostly = {
 469 +       .kind           = "imq",
 470 +       .priv_size      = 0,
 471 +       .setup          = imq_setup,
 472 +       .validate       = imq_validate,
 473 +};
 474 +
 475 +static int __init imq_init_hooks(void)
 476 +{
 477 +       int err;
 478 +
 479 +       nf_register_queue_imq_handler(&nfqh);
 480 +
 481 +       err = nf_register_hook(&imq_ingress_ipv4);
 482 +       if (err)
 483 +               goto err1;
 484 +
 485 +       err = nf_register_hook(&imq_egress_ipv4);
 486 +       if (err)
 487 +               goto err2;
 488 +
 489 +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 490 +       err = nf_register_hook(&imq_ingress_ipv6);
 491 +       if (err)
 492 +               goto err3;
 493 +
 494 +       err = nf_register_hook(&imq_egress_ipv6);
 495 +       if (err)
 496 +               goto err4;
 497 +#endif
 498 +
 499 +       return 0;
 500 +
 501 +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 502 +err4:
 503 +       nf_unregister_hook(&imq_ingress_ipv6);
 504 +err3:
 505 +       nf_unregister_hook(&imq_egress_ipv4);
 506 +#endif
 507 +err2:
 508 +       nf_unregister_hook(&imq_ingress_ipv4);
 509 +err1:
 510 +       nf_unregister_queue_imq_handler();
 511 +       return err;
 512 +}
 513 +
 514 +static int __init imq_init_one(int index)
 515 +{
 516 +       struct net_device *dev;
 517 +       int ret;
 518 +
 519 +       dev = alloc_netdev(0, "imq%d", imq_setup);
 520 +       if (!dev)
 521 +               return -ENOMEM;
 522 +
 523 +       ret = dev_alloc_name(dev, dev->name);
 524 +       if (ret < 0)
 525 +               goto fail;
 526 +
 527 +       dev->rtnl_link_ops = &imq_link_ops;
 528 +       ret = register_netdevice(dev);
 529 +       if (ret < 0)
 530 +               goto fail;
 531 +
 532 +       return 0;
 533 +fail:
 534 +       free_netdev(dev);
 535 +       return ret;
 536 +}
 537 +
 538 +static int __init imq_init_devs(void)
 539 +{
 540 +       int err, i;
 541 +
 542 +       if (numdevs < 1 || numdevs > IMQ_MAX_DEVS) {
 543 +               printk(KERN_ERR "IMQ: numdevs has to be betweed 1 and %u\n",
 544 +                      IMQ_MAX_DEVS);
 545 +               return -EINVAL;
 546 +       }
 547 +
 548 +       rtnl_lock();
 549 +       err = __rtnl_link_register(&imq_link_ops);
 550 +
 551 +       for (i = 0; i < numdevs && !err; i++)
 552 +               err = imq_init_one(i);
 553 +
 554 +       if (err) {
 555 +               __rtnl_link_unregister(&imq_link_ops);
 556 +               memset(imq_devs_cache, 0, sizeof(imq_devs_cache));
 557 +       }
 558 +       rtnl_unlock();
 559 +
 560 +       return err;
 561 +}
 562 +
 563 +static int __init imq_init_module(void)
 564 +{
 565 +       int err;
 566 +
 567 +#if defined(CONFIG_IMQ_NUM_DEVS)
 568 +       BUILD_BUG_ON(CONFIG_IMQ_NUM_DEVS > 16);
 569 +       BUILD_BUG_ON(CONFIG_IMQ_NUM_DEVS < 2);
 570 +       BUILD_BUG_ON(CONFIG_IMQ_NUM_DEVS - 1 > IMQ_F_IFMASK);
 571 +#endif
 572 +
 573 +       err = imq_init_devs();
 574 +       if (err) {
 575 +               printk(KERN_ERR "IMQ: Error trying imq_init_devs(net)\n");
 576 +               return err;
 577 +       }
 578 +
 579 +       err = imq_init_hooks();
 580 +       if (err) {
 581 +               printk(KERN_ERR "IMQ: Error trying imq_init_hooks()\n");
 582 +               rtnl_link_unregister(&imq_link_ops);
 583 +               memset(imq_devs_cache, 0, sizeof(imq_devs_cache));
 584 +               return err;
 585 +       }
 586 +
 587 +       printk(KERN_INFO "IMQ driver loaded successfully.\n");
 588 +
 589 +#if defined(CONFIG_IMQ_BEHAVIOR_BA) || defined(CONFIG_IMQ_BEHAVIOR_BB)
 590 +       printk(KERN_INFO "\tHooking IMQ before NAT on PREROUTING.\n");
 591 +#else
 592 +       printk(KERN_INFO "\tHooking IMQ after NAT on PREROUTING.\n");
 593 +#endif
 594 +#if defined(CONFIG_IMQ_BEHAVIOR_AB) || defined(CONFIG_IMQ_BEHAVIOR_BB)
 595 +       printk(KERN_INFO "\tHooking IMQ before NAT on POSTROUTING.\n");
 596 +#else
 597 +       printk(KERN_INFO "\tHooking IMQ after NAT on POSTROUTING.\n");
 598 +#endif
 599 +
 600 +       return 0;
 601 +}
 602 +
 603 +static void __exit imq_unhook(void)
 604 +{
 605 +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 606 +       nf_unregister_hook(&imq_ingress_ipv6);
 607 +       nf_unregister_hook(&imq_egress_ipv6);
 608 +#endif
 609 +       nf_unregister_hook(&imq_ingress_ipv4);
 610 +       nf_unregister_hook(&imq_egress_ipv4);
 611 +
 612 +       nf_unregister_queue_imq_handler();
 613 +}
 614 +
 615 +static void __exit imq_cleanup_devs(void)
 616 +{
 617 +       rtnl_link_unregister(&imq_link_ops);
 618 +       memset(imq_devs_cache, 0, sizeof(imq_devs_cache));
 619 +}
 620 +
 621 +static void __exit imq_exit_module(void)
 622 +{
 623 +       imq_unhook();
 624 +       imq_cleanup_devs();
 625 +       printk(KERN_INFO "IMQ driver unloaded successfully.\n");
 626 +}
 627 +
 628 +module_init(imq_init_module);
 629 +module_exit(imq_exit_module);
 630 +
 631 +module_param(numdevs, int, 0);
 632 +MODULE_PARM_DESC(numdevs, "number of IMQ devices (how many imq* devices will "
 633 +                       "be created)");
 634 +MODULE_AUTHOR("http://www.linuximq.net");
 635 +MODULE_DESCRIPTION("Pseudo-driver for the intermediate queue device. See "
 636 +                       "http://www.linuximq.net/ for more information.");
 637 +MODULE_LICENSE("GPL");
 638 +MODULE_ALIAS_RTNL_LINK("imq");
 639 +
 640 diff -uNr linux-2.6.34/drivers/net/Kconfig linux-2.6.34-imq/drivers/net/Kconfig
 641 --- linux-2.6.34/drivers/net/Kconfig    2010-05-17 00:17:36.000000000 +0300
 642 +++ linux-2.6.34-imq/drivers/net/Kconfig        2010-06-02 10:05:45.752109073 +0300
 643 @@ -121,6 +121,129 @@
 644           To compile this driver as a module, choose M here: the module
 645           will be called eql.  If unsure, say N.
 646
 647 +config IMQ
 648 +       tristate "IMQ (intermediate queueing device) support"
 649 +       depends on NETDEVICES && NETFILTER
 650 +       ---help---
 651 +         The IMQ device(s) is used as placeholder for QoS queueing
 652 +         disciplines. Every packet entering/leaving the IP stack can be
 653 +         directed through the IMQ device where it's enqueued/dequeued to the
 654 +         attached qdisc. This allows you to treat network devices as classes
 655 +         and distribute bandwidth among them. Iptables is used to specify
 656 +         through which IMQ device, if any, packets travel.
 657 +
 658 +         More information at: http://www.linuximq.net/
 659 +
 660 +         To compile this driver as a module, choose M here: the module
 661 +         will be called imq.  If unsure, say N.
 662 +
 663 +choice
 664 +       prompt "IMQ behavior (PRE/POSTROUTING)"
 665 +       depends on IMQ
 666 +       default IMQ_BEHAVIOR_AB
 667 +       help
 668 +
 669 +               This settings defines how IMQ behaves in respect to its
 670 +               hooking in PREROUTING and POSTROUTING.
 671 +
 672 +               IMQ can work in any of the following ways:
 673 +
 674 +                   PREROUTING   |      POSTROUTING
 675 +               -----------------|-------------------
 676 +               #1  After NAT    |      After NAT
 677 +               #2  After NAT    |      Before NAT
 678 +               #3  Before NAT   |      After NAT
 679 +               #4  Before NAT   |      Before NAT
 680 +
 681 +               The default behavior is to hook before NAT on PREROUTING
 682 +               and after NAT on POSTROUTING (#3).
 683 +
 684 +               This settings are specially usefull when trying to use IMQ
 685 +               to shape NATed clients.
 686 +
 687 +               More information can be found at: www.linuximq.net
 688 +
 689 +               If not sure leave the default settings alone.
 690 +
 691 +config IMQ_BEHAVIOR_AA
 692 +       bool "IMQ AA"
 693 +       help
 694 +               This settings defines how IMQ behaves in respect to its
 695 +               hooking in PREROUTING and POSTROUTING.
 696 +
 697 +               Choosing this option will make IMQ hook like this:
 698 +
 699 +               PREROUTING:   After NAT
 700 +               POSTROUTING:  After NAT
 701 +
 702 +               More information can be found at: www.linuximq.net
 703 +
 704 +               If not sure leave the default settings alone.
 705 +
 706 +config IMQ_BEHAVIOR_AB
 707 +       bool "IMQ AB"
 708 +       help
 709 +               This settings defines how IMQ behaves in respect to its
 710 +               hooking in PREROUTING and POSTROUTING.
 711 +
 712 +               Choosing this option will make IMQ hook like this:
 713 +
 714 +               PREROUTING:   After NAT
 715 +               POSTROUTING:  Before NAT
 716 +
 717 +               More information can be found at: www.linuximq.net
 718 +
 719 +               If not sure leave the default settings alone.
 720 +
 721 +config IMQ_BEHAVIOR_BA
 722 +       bool "IMQ BA"
 723 +       help
 724 +               This settings defines how IMQ behaves in respect to its
 725 +               hooking in PREROUTING and POSTROUTING.
 726 +
 727 +               Choosing this option will make IMQ hook like this:
 728 +
 729 +               PREROUTING:   Before NAT
 730 +               POSTROUTING:  After NAT
 731 +
 732 +               More information can be found at: www.linuximq.net
 733 +
 734 +               If not sure leave the default settings alone.
 735 +
 736 +config IMQ_BEHAVIOR_BB
 737 +       bool "IMQ BB"
 738 +       help
 739 +               This settings defines how IMQ behaves in respect to its
 740 +               hooking in PREROUTING and POSTROUTING.
 741 +
 742 +               Choosing this option will make IMQ hook like this:
 743 +
 744 +               PREROUTING:   Before NAT
 745 +               POSTROUTING:  Before NAT
 746 +
 747 +               More information can be found at: www.linuximq.net
 748 +
 749 +               If not sure leave the default settings alone.
 750 +
 751 +endchoice
 752 +
 753 +config IMQ_NUM_DEVS
 754 +
 755 +       int "Number of IMQ devices"
 756 +       range 2 16
 757 +       depends on IMQ
 758 +       default "16"
 759 +       help
 760 +
 761 +               This settings defines how many IMQ devices will be
 762 +               created.
 763 +
 764 +               The default value is 16.
 765 +
 766 +               More information can be found at: www.linuximq.net
 767 +
 768 +               If not sure leave the default settings alone.
 769 +
 770  config TUN
 771         tristate "Universal TUN/TAP device driver support"
 772         select CRC32
 773 diff -uNr linux-2.6.34/drivers/net/Makefile linux-2.6.34-imq/drivers/net/Makefile
 774 --- linux-2.6.34/drivers/net/Makefile   2010-05-17 00:17:36.000000000 +0300
 775 +++ linux-2.6.34-imq/drivers/net/Makefile       2010-06-02 10:05:45.752109073 +0300
 776 @@ -169,6 +169,7 @@
 777  obj-$(CONFIG_XEN_NETDEV_FRONTEND) += xen-netfront.o
 778
 779  obj-$(CONFIG_DUMMY) += dummy.o
 780 +obj-$(CONFIG_IMQ) += imq.o
 781  obj-$(CONFIG_IFB) += ifb.o
 782  obj-$(CONFIG_MACVLAN) += macvlan.o
 783  obj-$(CONFIG_MACVTAP) += macvtap.o
 784 diff -uNr linux-2.6.34/include/linux/imq.h linux-2.6.34-imq/include/linux/imq.h
 785 --- linux-2.6.34/include/linux/imq.h    1970-01-01 02:00:00.000000000 +0200
 786 +++ linux-2.6.34-imq/include/linux/imq.h        2010-06-02 10:05:45.752109073 +0300
 787 @@ -0,0 +1,13 @@
 788 +#ifndef _IMQ_H
 789 +#define _IMQ_H
 790 +
 791 +/* IFMASK (16 device indexes, 0 to 15) and flag(s) fit in 5 bits */
 792 +#define IMQ_F_BITS     5
 793 +
 794 +#define IMQ_F_IFMASK   0x0f
 795 +#define IMQ_F_ENQUEUE  0x10
 796 +
 797 +#define IMQ_MAX_DEVS   (IMQ_F_IFMASK + 1)
 798 +
 799 +#endif /* _IMQ_H */
 800 +
 801 diff -uNr linux-2.6.34/include/linux/netdevice.h linux-2.6.34-imq/include/linux/netdevice.h
 802 --- linux-2.6.34/include/linux/netdevice.h      2010-05-17 00:17:36.000000000 +0300
 803 +++ linux-2.6.34-imq/include/linux/netdevice.h  2010-06-02 10:05:45.752109073 +0300
 804 @@ -1203,6 +1203,7 @@
 805  extern int             dev_open(struct net_device *dev);
 806  extern int             dev_close(struct net_device *dev);
 807  extern void            dev_disable_lro(struct net_device *dev);
 808 +extern struct netdev_queue *dev_pick_tx(struct net_device *dev, struct sk_buff *skb);
 809  extern int             dev_queue_xmit(struct sk_buff *skb);
 810  extern int             register_netdevice(struct net_device *dev);
 811  extern void            unregister_netdevice_queue(struct net_device *dev,
 812 diff -uNr linux-2.6.34/include/linux/netfilter/xt_IMQ.h linux-2.6.34-imq/include/linux/netfilter/xt_IMQ.h
 813 --- linux-2.6.34/include/linux/netfilter/xt_IMQ.h       1970-01-01 02:00:00.000000000 +0200
 814 +++ linux-2.6.34-imq/include/linux/netfilter/xt_IMQ.h   2010-06-02 10:05:45.752109073 +0300
 815 @@ -0,0 +1,9 @@
 816 +#ifndef _XT_IMQ_H
 817 +#define _XT_IMQ_H
 818 +
 819 +struct xt_imq_info {
 820 +       unsigned int todev;     /* target imq device */
 821 +};
 822 +
 823 +#endif /* _XT_IMQ_H */
 824 +
 825 diff -uNr linux-2.6.34/include/linux/netfilter_ipv4/ipt_IMQ.h linux-2.6.34-imq/include/linux/netfilter_ipv4/ipt_IMQ.h
 826 --- linux-2.6.34/include/linux/netfilter_ipv4/ipt_IMQ.h 1970-01-01 02:00:00.000000000 +0200
 827 +++ linux-2.6.34-imq/include/linux/netfilter_ipv4/ipt_IMQ.h     2010-06-02 10:05:45.752109073 +0300
 828 @@ -0,0 +1,10 @@
 829 +#ifndef _IPT_IMQ_H
 830 +#define _IPT_IMQ_H
 831 +
 832 +/* Backwards compatibility for old userspace */
 833 +#include <linux/netfilter/xt_IMQ.h>
 834 +
 835 +#define ipt_imq_info xt_imq_info
 836 +
 837 +#endif /* _IPT_IMQ_H */
 838 +
 839 diff -uNr linux-2.6.34/include/linux/netfilter_ipv6/ip6t_IMQ.h linux-2.6.34-imq/include/linux/netfilter_ipv6/ip6t_IMQ.h
 840 --- linux-2.6.34/include/linux/netfilter_ipv6/ip6t_IMQ.h        1970-01-01 02:00:00.000000000 +0200
 841 +++ linux-2.6.34-imq/include/linux/netfilter_ipv6/ip6t_IMQ.h    2010-06-02 10:05:45.752109073 +0300
 842 @@ -0,0 +1,10 @@
 843 +#ifndef _IP6T_IMQ_H
 844 +#define _IP6T_IMQ_H
 845 +
 846 +/* Backwards compatibility for old userspace */
 847 +#include <linux/netfilter/xt_IMQ.h>
 848 +
 849 +#define ip6t_imq_info xt_imq_info
 850 +
 851 +#endif /* _IP6T_IMQ_H */
 852 +
 853 diff -uNr linux-2.6.34/include/linux/skbuff.h linux-2.6.34-imq/include/linux/skbuff.h
 854 --- linux-2.6.34/include/linux/skbuff.h 2010-05-17 00:17:36.000000000 +0300
 855 +++ linux-2.6.34-imq/include/linux/skbuff.h     2010-06-02 10:05:45.752109073 +0300
 856 @@ -29,6 +29,9 @@
 857  #include <linux/rcupdate.h>
 858  #include <linux/dmaengine.h>
 859  #include <linux/hrtimer.h>
 860 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
 861 +#include <linux/imq.h>
 862 +#endif
 863
 864  /* Don't change this without changing skb_csum_unnecessary! */
 865  #define CHECKSUM_NONE 0
 866 @@ -321,6 +324,9 @@
 867          * first. This is owned by whoever has the skb queued ATM.
 868          */
 869         char                    cb[48] __aligned(8);
 870 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
 871 +       void                    *cb_next;
 872 +#endif
 873
 874         unsigned long           _skb_dst;
 875  #ifdef CONFIG_XFRM
 876 @@ -357,6 +363,9 @@
 877         struct nf_conntrack     *nfct;
 878         struct sk_buff          *nfct_reasm;
 879  #endif
 880 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
 881 +       struct nf_queue_entry   *nf_queue_entry;
 882 +#endif
 883  #ifdef CONFIG_BRIDGE_NETFILTER
 884         struct nf_bridge_info   *nf_bridge;
 885  #endif
 886 @@ -378,6 +387,10 @@
 887
 888         /* 0/14 bit hole */
 889
 890 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
 891 +       __u8                    imq_flags:IMQ_F_BITS;
 892 +#endif
 893 +
 894  #ifdef CONFIG_NET_DMA
 895         dma_cookie_t            dma_cookie;
 896  #endif
 897 @@ -426,6 +439,12 @@
 898         return (struct rtable *)skb_dst(skb);
 899  }
 900
 901 +
 902 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
 903 +extern int skb_save_cb(struct sk_buff *skb);
 904 +extern int skb_restore_cb(struct sk_buff *skb);
 905 +#endif
 906 +
 907  extern void kfree_skb(struct sk_buff *skb);
 908  extern void consume_skb(struct sk_buff *skb);
 909  extern void           __kfree_skb(struct sk_buff *skb);
 910 @@ -1970,6 +1989,10 @@
 911         dst->nfct_reasm = src->nfct_reasm;
 912         nf_conntrack_get_reasm(src->nfct_reasm);
 913  #endif
 914 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
 915 +       dst->imq_flags = src->imq_flags;
 916 +       dst->nf_queue_entry = src->nf_queue_entry;
 917 +#endif
 918  #ifdef CONFIG_BRIDGE_NETFILTER
 919         dst->nf_bridge  = src->nf_bridge;
 920         nf_bridge_get(src->nf_bridge);
 921 diff -uNr linux-2.6.34/include/net/netfilter/nf_queue.h linux-2.6.34-imq/include/net/netfilter/nf_queue.h
 922 --- linux-2.6.34/include/net/netfilter/nf_queue.h       2010-05-17 00:17:36.000000000 +0300
 923 +++ linux-2.6.34-imq/include/net/netfilter/nf_queue.h   2010-06-02 10:05:45.752109073 +0300
 924 @@ -13,6 +13,12 @@
 925         struct net_device       *indev;
 926         struct net_device       *outdev;
 927         int                     (*okfn)(struct sk_buff *);
 928 +
 929 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
 930 +       int                     (*next_outfn)(struct nf_queue_entry *entry,
 931 +                                             unsigned int queuenum);
 932 +       unsigned int            next_queuenum;
 933 +#endif
 934  };
 935
 936  #define nf_queue_entry_reroute(x) ((void *)x + sizeof(struct nf_queue_entry))
 937 @@ -30,5 +36,11 @@
 938                                        const struct nf_queue_handler *qh);
 939  extern void nf_unregister_queue_handlers(const struct nf_queue_handler *qh);
 940  extern void nf_reinject(struct nf_queue_entry *entry, unsigned int verdict);
 941 +extern void nf_queue_entry_release_refs(struct nf_queue_entry *entry);
 942 +
 943 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
 944 +extern void nf_register_queue_imq_handler(const struct nf_queue_handler *qh);
 945 +extern void nf_unregister_queue_imq_handler(void);
 946 +#endif
 947
 948  #endif /* _NF_QUEUE_H */
 949 diff -uNr linux-2.6.34/net/core/dev.c linux-2.6.34-imq/net/core/dev.c
 950 --- linux-2.6.34/net/core/dev.c 2010-05-17 00:17:36.000000000 +0300
 951 +++ linux-2.6.34-imq/net/core/dev.c     2010-06-02 10:05:45.752109073 +0300
 952 @@ -98,6 +98,9 @@
 953  #include <net/net_namespace.h>
 954  #include <net/sock.h>
 955  #include <linux/rtnetlink.h>
 956 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
 957 +#include <linux/imq.h>
 958 +#endif
 959  #include <linux/proc_fs.h>
 960  #include <linux/seq_file.h>
 961  #include <linux/stat.h>
 962 @@ -1859,7 +1862,11 @@
 963         int rc = NETDEV_TX_OK;
 964
 965         if (likely(!skb->next)) {
 966 -               if (!list_empty(&ptype_all))
 967 +               if (!list_empty(&ptype_all)
 968 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
 969 +                       && !(skb->imq_flags & IMQ_F_ENQUEUE)
 970 +#endif
 971 +                  )
 972                         dev_queue_xmit_nit(skb, dev);
 973
 974                 if (netif_needs_gso(dev, skb)) {
 975 @@ -1969,8 +1976,7 @@
 976         return queue_index;
 977  }
 978
 979 -static struct netdev_queue *dev_pick_tx(struct net_device *dev,
 980 -                                       struct sk_buff *skb)
 981 +struct netdev_queue *dev_pick_tx(struct net_device *dev, struct sk_buff *skb)
 982  {
 983         u16 queue_index;
 984         struct sock *sk = skb->sk;
 985 @@ -2000,6 +2006,7 @@
 986         skb_set_queue_mapping(skb, queue_index);
 987         return netdev_get_tx_queue(dev, queue_index);
 988  }
 989 +EXPORT_SYMBOL(dev_pick_tx);
 990
 991  static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
 992                                  struct net_device *dev,
 993 diff -uNr linux-2.6.34/net/core/skbuff.c linux-2.6.34-imq/net/core/skbuff.c
 994 --- linux-2.6.34/net/core/skbuff.c      2010-05-17 00:17:36.000000000 +0300
 995 +++ linux-2.6.34-imq/net/core/skbuff.c  2010-06-02 10:05:45.752109073 +0300
 996 @@ -72,6 +72,9 @@
 997
 998  static struct kmem_cache *skbuff_head_cache __read_mostly;
 999  static struct kmem_cache *skbuff_fclone_cache __read_mostly;
1000 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1001 +static struct kmem_cache *skbuff_cb_store_cache __read_mostly;
1002 +#endif
1003
1004  static void sock_pipe_buf_release(struct pipe_inode_info *pipe,
1005                                   struct pipe_buffer *buf)
1006 @@ -91,6 +94,83 @@
1007         return 1;
1008  }
1009
1010 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1011 +/* Control buffer save/restore for IMQ devices */
1012 +struct skb_cb_table {
1013 +       void                    *cb_next;
1014 +       atomic_t                refcnt;
1015 +       char                    cb[48];
1016 +};
1017 +
1018 +static DEFINE_SPINLOCK(skb_cb_store_lock);
1019 +
1020 +int skb_save_cb(struct sk_buff *skb)
1021 +{
1022 +       struct skb_cb_table *next;
1023 +
1024 +       next = kmem_cache_alloc(skbuff_cb_store_cache, GFP_ATOMIC);
1025 +       if (!next)
1026 +               return -ENOMEM;
1027 +
1028 +       BUILD_BUG_ON(sizeof(skb->cb) != sizeof(next->cb));
1029 +
1030 +       memcpy(next->cb, skb->cb, sizeof(skb->cb));
1031 +       next->cb_next = skb->cb_next;
1032 +
1033 +       atomic_set(&next->refcnt, 1);
1034 +
1035 +       skb->cb_next = next;
1036 +       return 0;
1037 +}
1038 +EXPORT_SYMBOL(skb_save_cb);
1039 +
1040 +int skb_restore_cb(struct sk_buff *skb)
1041 +{
1042 +       struct skb_cb_table *next;
1043 +
1044 +       if (!skb->cb_next)
1045 +               return 0;
1046 +
1047 +       next = skb->cb_next;
1048 +
1049 +       BUILD_BUG_ON(sizeof(skb->cb) != sizeof(next->cb));
1050 +
1051 +       memcpy(skb->cb, next->cb, sizeof(skb->cb));
1052 +       skb->cb_next = next->cb_next;
1053 +
1054 +       spin_lock(&skb_cb_store_lock);
1055 +
1056 +       if (atomic_dec_and_test(&next->refcnt)) {
1057 +               kmem_cache_free(skbuff_cb_store_cache, next);
1058 +       }
1059 +
1060 +       spin_unlock(&skb_cb_store_lock);
1061 +
1062 +       return 0;
1063 +}
1064 +EXPORT_SYMBOL(skb_restore_cb);
1065 +
1066 +static void skb_copy_stored_cb(struct sk_buff *new, const struct sk_buff *__old)
1067 +{
1068 +       struct skb_cb_table *next;
1069 +       struct sk_buff *old;
1070 +
1071 +       if (!__old->cb_next) {
1072 +               new->cb_next = NULL;
1073 +               return;
1074 +       }
1075 +
1076 +       spin_lock(&skb_cb_store_lock);
1077 +
1078 +       old = (struct sk_buff *)__old;
1079 +
1080 +       next = old->cb_next;
1081 +       atomic_inc(&next->refcnt);
1082 +       new->cb_next = next;
1083 +
1084 +       spin_unlock(&skb_cb_store_lock);
1085 +}
1086 +#endif
1087
1088  /* Pipe buffer operations for a socket. */
1089  static const struct pipe_buf_operations sock_pipe_buf_ops = {
1090 @@ -398,6 +478,26 @@
1091                 WARN_ON(in_irq());
1092                 skb->destructor(skb);
1093         }
1094 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1095 +       /* This should not happen. When it does, avoid memleak by restoring
1096 +       the chain of cb-backups. */
1097 +       while(skb->cb_next != NULL) {
1098 +               if (net_ratelimit())
1099 +                       printk(KERN_WARNING "IMQ: kfree_skb: skb->cb_next: "
1100 +                               "%08x\n", (unsigned int)skb->cb_next);
1101 +
1102 +               skb_restore_cb(skb);
1103 +       }
1104 +       /* This should not happen either, nf_queue_entry is nullified in
1105 +        * imq_dev_xmit(). If we have non-NULL nf_queue_entry then we are
1106 +        * leaking entry pointers, maybe memory. We don't know if this is
1107 +        * pointer to already freed memory, or should this be freed.
1108 +        * If this happens we need to add refcounting, etc for nf_queue_entry.
1109 +        */
1110 +       if (skb->nf_queue_entry && net_ratelimit())
1111 +               printk(KERN_WARNING
1112 +                               "IMQ: kfree_skb: skb->nf_queue_entry != NULL");
1113 +#endif
1114  #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
1115         nf_conntrack_put(skb->nfct);
1116         nf_conntrack_put_reasm(skb->nfct_reasm);
1117 @@ -538,6 +638,9 @@
1118         new->sp                 = secpath_get(old->sp);
1119  #endif
1120         memcpy(new->cb, old->cb, sizeof(old->cb));
1121 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1122 +       skb_copy_stored_cb(new, old);
1123 +#endif
1124         new->csum               = old->csum;
1125         new->local_df           = old->local_df;
1126         new->pkt_type           = old->pkt_type;
1127 @@ -2779,6 +2882,13 @@
1128                                                 0,
1129                                                 SLAB_HWCACHE_ALIGN|SLAB_PANIC,
1130                                                 NULL);
1131 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1132 +       skbuff_cb_store_cache = kmem_cache_create("skbuff_cb_store_cache",
1133 +                                                 sizeof(struct skb_cb_table),
1134 +                                                 0,
1135 +                                                 SLAB_HWCACHE_ALIGN|SLAB_PANIC,
1136 +                                                 NULL);
1137 +#endif
1138  }
1139
1140  /**
1141 diff -uNr linux-2.6.34/net/netfilter/Kconfig linux-2.6.34-imq/net/netfilter/Kconfig
1142 --- linux-2.6.34/net/netfilter/Kconfig  2010-05-17 00:17:36.000000000 +0300
1143 +++ linux-2.6.34-imq/net/netfilter/Kconfig      2010-06-02 10:05:45.762097870 +0300
1144 @@ -421,6 +421,18 @@
1145           For more information on the LEDs available on your system, see
1146           Documentation/leds-class.txt
1147
1148 +config NETFILTER_XT_TARGET_IMQ
1149 +        tristate '"IMQ" target support'
1150 +       depends on NETFILTER_XTABLES
1151 +       depends on IP_NF_MANGLE || IP6_NF_MANGLE
1152 +       select IMQ
1153 +       default m if NETFILTER_ADVANCED=n
1154 +        help
1155 +          This option adds a `IMQ' target which is used to specify if and
1156 +          to which imq device packets should get enqueued/dequeued.
1157 +
1158 +          To compile it as a module, choose M here.  If unsure, say N.
1159 +
1160  config NETFILTER_XT_TARGET_MARK
1161         tristate '"MARK" target support'
1162         default m if NETFILTER_ADVANCED=n
1163 diff -uNr linux-2.6.34/net/netfilter/Makefile linux-2.6.34-imq/net/netfilter/Makefile
1164 --- linux-2.6.34/net/netfilter/Makefile 2010-05-17 00:17:36.000000000 +0300
1165 +++ linux-2.6.34-imq/net/netfilter/Makefile     2010-06-02 10:05:45.762097870 +0300
1166 @@ -47,6 +47,7 @@
1167  obj-$(CONFIG_NETFILTER_XT_TARGET_CT) += xt_CT.o
1168  obj-$(CONFIG_NETFILTER_XT_TARGET_DSCP) += xt_DSCP.o
1169  obj-$(CONFIG_NETFILTER_XT_TARGET_HL) += xt_HL.o
1170 +obj-$(CONFIG_NETFILTER_XT_TARGET_IMQ) += xt_IMQ.o
1171  obj-$(CONFIG_NETFILTER_XT_TARGET_LED) += xt_LED.o
1172  obj-$(CONFIG_NETFILTER_XT_TARGET_MARK) += xt_MARK.o
1173  obj-$(CONFIG_NETFILTER_XT_TARGET_NFLOG) += xt_NFLOG.o
1174 diff -uNr linux-2.6.34/net/netfilter/nf_queue.c linux-2.6.34-imq/net/netfilter/nf_queue.c
1175 --- linux-2.6.34/net/netfilter/nf_queue.c       2010-05-17 00:17:36.000000000 +0300
1176 +++ linux-2.6.34-imq/net/netfilter/nf_queue.c   2010-06-02 10:05:45.762097870 +0300
1177 @@ -21,6 +21,26 @@
1178
1179  static DEFINE_MUTEX(queue_handler_mutex);
1180
1181 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1182 +static const struct nf_queue_handler *queue_imq_handler;
1183 +
1184 +void nf_register_queue_imq_handler(const struct nf_queue_handler *qh)
1185 +{
1186 +       mutex_lock(&queue_handler_mutex);
1187 +       rcu_assign_pointer(queue_imq_handler, qh);
1188 +       mutex_unlock(&queue_handler_mutex);
1189 +}
1190 +EXPORT_SYMBOL(nf_register_queue_imq_handler);
1191 +
1192 +void nf_unregister_queue_imq_handler(void)
1193 +{
1194 +       mutex_lock(&queue_handler_mutex);
1195 +       rcu_assign_pointer(queue_imq_handler, NULL);
1196 +       mutex_unlock(&queue_handler_mutex);
1197 +}
1198 +EXPORT_SYMBOL(nf_unregister_queue_imq_handler);
1199 +#endif
1200 +
1201  /* return EBUSY when somebody else is registered, return EEXIST if the
1202   * same handler is registered, return 0 in case of success. */
1203  int nf_register_queue_handler(u_int8_t pf, const struct nf_queue_handler *qh)
1204 @@ -81,7 +101,7 @@
1205  }
1206  EXPORT_SYMBOL_GPL(nf_unregister_queue_handlers);
1207
1208 -static void nf_queue_entry_release_refs(struct nf_queue_entry *entry)
1209 +void nf_queue_entry_release_refs(struct nf_queue_entry *entry)
1210  {
1211         /* Release those devices we held, or Alexey will kill me. */
1212         if (entry->indev)
1213 @@ -101,6 +121,7 @@
1214         /* Drop reference to owner of hook which queued us. */
1215         module_put(entry->elem->owner);
1216  }
1217 +EXPORT_SYMBOL_GPL(nf_queue_entry_release_refs);
1218
1219  /*
1220   * Any packet that leaves via this function must come back
1221 @@ -122,12 +143,26 @@
1222  #endif
1223         const struct nf_afinfo *afinfo;
1224         const struct nf_queue_handler *qh;
1225 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1226 +       const struct nf_queue_handler *qih = NULL;
1227 +#endif
1228
1229         /* QUEUE == DROP if noone is waiting, to be safe. */
1230         rcu_read_lock();
1231
1232         qh = rcu_dereference(queue_handler[pf]);
1233 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1234 +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1235 +       if (pf == PF_INET || pf == PF_INET6)
1236 +#else
1237 +       if (pf == PF_INET)
1238 +#endif
1239 +               qih = rcu_dereference(queue_imq_handler);
1240 +
1241 +       if (!qh && !qih)
1242 +#else /* !IMQ */
1243         if (!qh)
1244 +#endif
1245                 goto err_unlock;
1246
1247         afinfo = nf_get_afinfo(pf);
1248 @@ -146,6 +181,10 @@
1249                 .indev  = indev,
1250                 .outdev = outdev,
1251                 .okfn   = okfn,
1252 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1253 +               .next_outfn = qh ? qh->outfn : NULL,
1254 +               .next_queuenum = queuenum,
1255 +#endif
1256         };
1257
1258         /* If it's going away, ignore hook. */
1259 @@ -171,8 +210,19 @@
1260         }
1261  #endif
1262         afinfo->saveroute(skb, entry);
1263 +
1264 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1265 +       if (qih) {
1266 +               status = qih->outfn(entry, queuenum);
1267 +               goto imq_skip_queue;
1268 +       }
1269 +#endif
1270 +
1271         status = qh->outfn(entry, queuenum);
1272
1273 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1274 +imq_skip_queue:
1275 +#endif
1276         rcu_read_unlock();
1277
1278         if (status < 0) {
1279 diff -uNr linux-2.6.34/net/netfilter/xt_IMQ.c linux-2.6.34-imq/net/netfilter/xt_IMQ.c
1280 --- linux-2.6.34/net/netfilter/xt_IMQ.c 1970-01-01 02:00:00.000000000 +0200
1281 +++ linux-2.6.34-imq/net/netfilter/xt_IMQ.c     2010-06-02 10:05:45.762097870 +0300
1282 @@ -0,0 +1,73 @@
1283 +/*
1284 + * This target marks packets to be enqueued to an imq device
1285 + */
1286 +#include <linux/module.h>
1287 +#include <linux/skbuff.h>
1288 +#include <linux/netfilter/x_tables.h>
1289 +#include <linux/netfilter/xt_IMQ.h>
1290 +#include <linux/imq.h>
1291 +
1292 +static unsigned int imq_target(struct sk_buff *pskb,
1293 +                               const struct xt_target_param *par)
1294 +{
1295 +       const struct xt_imq_info *mr = par->targinfo;
1296 +
1297 +       pskb->imq_flags = (mr->todev & IMQ_F_IFMASK) | IMQ_F_ENQUEUE;
1298 +
1299 +       return XT_CONTINUE;
1300 +}
1301 +
1302 +static bool imq_checkentry(const struct xt_tgchk_param *par)
1303 +{
1304 +       struct xt_imq_info *mr = par->targinfo;
1305 +
1306 +       if (mr->todev > IMQ_MAX_DEVS - 1) {
1307 +               printk(KERN_WARNING
1308 +                      "IMQ: invalid device specified, highest is %u\n",
1309 +                      IMQ_MAX_DEVS - 1);
1310 +               return 0;
1311 +       }
1312 +
1313 +       return 1;
1314 +}
1315 +
1316 +static struct xt_target xt_imq_reg[] __read_mostly = {
1317 +       {
1318 +               .name           = "IMQ",
1319 +               .family         = AF_INET,
1320 +               .checkentry     = imq_checkentry,
1321 +               .target         = imq_target,
1322 +               .targetsize     = sizeof(struct xt_imq_info),
1323 +               .table          = "mangle",
1324 +               .me             = THIS_MODULE
1325 +       },
1326 +       {
1327 +               .name           = "IMQ",
1328 +               .family         = AF_INET6,
1329 +               .checkentry     = imq_checkentry,
1330 +               .target         = imq_target,
1331 +               .targetsize     = sizeof(struct xt_imq_info),
1332 +               .table          = "mangle",
1333 +               .me             = THIS_MODULE
1334 +       },
1335 +};
1336 +
1337 +static int __init imq_init(void)
1338 +{
1339 +       return xt_register_targets(xt_imq_reg, ARRAY_SIZE(xt_imq_reg));
1340 +}
1341 +
1342 +static void __exit imq_fini(void)
1343 +{
1344 +       xt_unregister_targets(xt_imq_reg, ARRAY_SIZE(xt_imq_reg));
1345 +}
1346 +
1347 +module_init(imq_init);
1348 +module_exit(imq_fini);
1349 +
1350 +MODULE_AUTHOR("http://www.linuximq.net");
1351 +MODULE_DESCRIPTION("Pseudo-driver for the intermediate queue device. See http://www.linuximq.net/ for more information.");
1352 +MODULE_LICENSE("GPL");
1353 +MODULE_ALIAS("ipt_IMQ");
1354 +MODULE_ALIAS("ip6t_IMQ");
1355 +