kernel-imq.patch

   1 net: add Intermediate Queueing Device (imq)
   2
   3 From: Jussi Kivilinna <jussi.kivilinna@iki.fi>
   4
   5 See: http://linuximq.net/
   6
   7 Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
   8 ---
   9  drivers/net/Kconfig                     |  119 ++++
  10  drivers/net/Makefile                    |    1
  11  drivers/net/imq.c                       | 1001 +++++++++++++++++++++++++++++++
  12  include/linux/imq.h                     |   13
  13  include/linux/netfilter/xt_IMQ.h        |    9
  14  include/linux/netfilter_ipv4/ipt_IMQ.h  |   10
  15  include/linux/netfilter_ipv6/ip6t_IMQ.h |   10
  16  include/linux/skbuff.h                  |   23 +
  17  include/net/netfilter/nf_queue.h        |    6
  18  include/uapi/linux/netfilter.h          |    3
  19  net/core/dev.c                          |    8
  20  net/core/skbuff.c                       |  112 +++
  21  net/ipv6/ip6_output.c                   |   10
  22  net/netfilter/Kconfig                   |   12
  23  net/netfilter/Makefile                  |    1
  24  net/netfilter/core.c                    |    6
  25  net/netfilter/nf_internals.h            |    2
  26  net/netfilter/nf_queue.c                |   36 +
  27  net/netfilter/xt_IMQ.c                  |   72 ++
  28  19 files changed, 1444 insertions(+), 10 deletions(-)
  29  create mode 100644 drivers/net/imq.c
  30  create mode 100644 include/linux/imq.h
  31  create mode 100644 include/linux/netfilter/xt_IMQ.h
  32  create mode 100644 include/linux/netfilter_ipv4/ipt_IMQ.h
  33  create mode 100644 include/linux/netfilter_ipv6/ip6t_IMQ.h
  34  create mode 100644 net/netfilter/xt_IMQ.c
  35
  36 diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
  37 index 3835321..77550a9 100644
  38 --- a/drivers/net/Kconfig
  39 +++ b/drivers/net/Kconfig
  40 @@ -207,6 +207,125 @@ config RIONET_RX_SIZE
  41         depends on RIONET
  42         default "128"
  43
  44 +config IMQ
  45 +       tristate "IMQ (intermediate queueing device) support"
  46 +       depends on NETDEVICES && NETFILTER
  47 +       ---help---
  48 +         The IMQ device(s) is used as placeholder for QoS queueing
  49 +         disciplines. Every packet entering/leaving the IP stack can be
  50 +         directed through the IMQ device where it's enqueued/dequeued to the
  51 +         attached qdisc. This allows you to treat network devices as classes
  52 +         and distribute bandwidth among them. Iptables is used to specify
  53 +         through which IMQ device, if any, packets travel.
  54 +
  55 +         More information at: http://www.linuximq.net/
  56 +
  57 +         To compile this driver as a module, choose M here: the module
  58 +         will be called imq.  If unsure, say N.
  59 +
  60 +choice
  61 +       prompt "IMQ behavior (PRE/POSTROUTING)"
  62 +       depends on IMQ
  63 +       default IMQ_BEHAVIOR_AB
  64 +       help
  65 +         This setting defines how IMQ behaves in respect to its
  66 +         hooking in PREROUTING and POSTROUTING.
  67 +
  68 +         IMQ can work in any of the following ways:
  69 +
  70 +             PREROUTING   |      POSTROUTING
  71 +         -----------------|-------------------
  72 +         #1  After NAT    |      After NAT
  73 +         #2  After NAT    |      Before NAT
  74 +         #3  Before NAT   |      After NAT
  75 +         #4  Before NAT   |      Before NAT
  76 +
  77 +         The default behavior is to hook before NAT on PREROUTING
  78 +         and after NAT on POSTROUTING (#3).
  79 +
  80 +         This settings are specially usefull when trying to use IMQ
  81 +         to shape NATed clients.
  82 +
  83 +         More information can be found at: www.linuximq.net
  84 +
  85 +         If not sure leave the default settings alone.
  86 +
  87 +config IMQ_BEHAVIOR_AA
  88 +       bool "IMQ AA"
  89 +       help
  90 +         This setting defines how IMQ behaves in respect to its
  91 +         hooking in PREROUTING and POSTROUTING.
  92 +
  93 +         Choosing this option will make IMQ hook like this:
  94 +
  95 +         PREROUTING:   After NAT
  96 +         POSTROUTING:  After NAT
  97 +
  98 +         More information can be found at: www.linuximq.net
  99 +
 100 +         If not sure leave the default settings alone.
 101 +
 102 +config IMQ_BEHAVIOR_AB
 103 +       bool "IMQ AB"
 104 +       help
 105 +         This setting defines how IMQ behaves in respect to its
 106 +         hooking in PREROUTING and POSTROUTING.
 107 +
 108 +         Choosing this option will make IMQ hook like this:
 109 +
 110 +         PREROUTING:   After NAT
 111 +         POSTROUTING:  Before NAT
 112 +
 113 +         More information can be found at: www.linuximq.net
 114 +
 115 +         If not sure leave the default settings alone.
 116 +
 117 +config IMQ_BEHAVIOR_BA
 118 +       bool "IMQ BA"
 119 +       help
 120 +         This setting defines how IMQ behaves in respect to its
 121 +         hooking in PREROUTING and POSTROUTING.
 122 +
 123 +         Choosing this option will make IMQ hook like this:
 124 +
 125 +         PREROUTING:   Before NAT
 126 +         POSTROUTING:  After NAT
 127 +
 128 +         More information can be found at: www.linuximq.net
 129 +
 130 +         If not sure leave the default settings alone.
 131 +
 132 +config IMQ_BEHAVIOR_BB
 133 +       bool "IMQ BB"
 134 +       help
 135 +         This setting defines how IMQ behaves in respect to its
 136 +         hooking in PREROUTING and POSTROUTING.
 137 +
 138 +         Choosing this option will make IMQ hook like this:
 139 +
 140 +         PREROUTING:   Before NAT
 141 +         POSTROUTING:  Before NAT
 142 +
 143 +         More information can be found at: www.linuximq.net
 144 +
 145 +         If not sure leave the default settings alone.
 146 +
 147 +endchoice
 148 +
 149 +config IMQ_NUM_DEVS
 150 +       int "Number of IMQ devices"
 151 +       range 2 16
 152 +       depends on IMQ
 153 +       default "16"
 154 +       help
 155 +         This setting defines how many IMQ devices will be created.
 156 +
 157 +         The default value is 16.
 158 +
 159 +         More information can be found at: www.linuximq.net
 160 +
 161 +         If not sure leave the default settings alone.
 162 +
 163  config TUN
 164         tristate "Universal TUN/TAP device driver support"
 165         select CRC32
 166 diff --git a/drivers/net/Makefile b/drivers/net/Makefile
 167 index ef3d090..b474ff4 100644
 168 --- a/drivers/net/Makefile
 169 +++ b/drivers/net/Makefile
 170 @@ -9,6 +9,7 @@ obj-$(CONFIG_BONDING) += bonding/
 171  obj-$(CONFIG_DUMMY) += dummy.o
 172  obj-$(CONFIG_EQUALIZER) += eql.o
 173  obj-$(CONFIG_IFB) += ifb.o
 174 +obj-$(CONFIG_IMQ) += imq.o
 175  obj-$(CONFIG_MACVLAN) += macvlan.o
 176  obj-$(CONFIG_MACVTAP) += macvtap.o
 177  obj-$(CONFIG_MII) += mii.o
 178 diff --git a/drivers/net/imq.c b/drivers/net/imq.c
 179 new file mode 100644
 180 index 0000000..fd3e6c5
 181 --- /dev/null
 182 +++ b/drivers/net/imq.c
 183 @@ -0,0 +1,1001 @@
 184 +/*
 185 + *             Pseudo-driver for the intermediate queue device.
 186 + *
 187 + *             This program is free software; you can redistribute it and/or
 188 + *             modify it under the terms of the GNU General Public License
 189 + *             as published by the Free Software Foundation; either version
 190 + *             2 of the License, or (at your option) any later version.
 191 + *
 192 + * Authors:    Patrick McHardy, <kaber@trash.net>
 193 + *
 194 + *            The first version was written by Martin Devera, <devik@cdi.cz>
 195 + *
 196 + * Credits:    Jan Rafaj <imq2t@cedric.vabo.cz>
 197 + *              - Update patch to 2.4.21
 198 + *             Sebastian Strollo <sstrollo@nortelnetworks.com>
 199 + *              - Fix "Dead-loop on netdevice imq"-issue
 200 + *             Marcel Sebek <sebek64@post.cz>
 201 + *              - Update to 2.6.2-rc1
 202 + *
 203 + *            After some time of inactivity there is a group taking care
 204 + *            of IMQ again: http://www.linuximq.net
 205 + *
 206 + *
 207 + *            2004/06/30 - New version of IMQ patch to kernels <=2.6.7
 208 + *             including the following changes:
 209 + *
 210 + *            - Correction of ipv6 support "+"s issue (Hasso Tepper)
 211 + *            - Correction of imq_init_devs() issue that resulted in
 212 + *            kernel OOPS unloading IMQ as module (Norbert Buchmuller)
 213 + *            - Addition of functionality to choose number of IMQ devices
 214 + *            during kernel config (Andre Correa)
 215 + *            - Addition of functionality to choose how IMQ hooks on
 216 + *            PRE and POSTROUTING (after or before NAT) (Andre Correa)
 217 + *            - Cosmetic corrections (Norbert Buchmuller) (Andre Correa)
 218 + *
 219 + *
 220 + *             2005/12/16 - IMQ versions between 2.6.7 and 2.6.13 were
 221 + *             released with almost no problems. 2.6.14-x was released
 222 + *             with some important changes: nfcache was removed; After
 223 + *             some weeks of trouble we figured out that some IMQ fields
 224 + *             in skb were missing in skbuff.c - skb_clone and copy_skb_header.
 225 + *             These functions are correctly patched by this new patch version.
 226 + *
 227 + *             Thanks for all who helped to figure out all the problems with
 228 + *             2.6.14.x: Patrick McHardy, Rune Kock, VeNoMouS, Max CtRiX,
 229 + *             Kevin Shanahan, Richard Lucassen, Valery Dachev (hopefully
 230 + *             I didn't forget anybody). I apologize again for my lack of time.
 231 + *
 232 + *
 233 + *             2008/06/17 - 2.6.25 - Changed imq.c to use qdisc_run() instead
 234 + *             of qdisc_restart() and moved qdisc_run() to tasklet to avoid
 235 + *             recursive locking. New initialization routines to fix 'rmmod' not
 236 + *             working anymore. Used code from ifb.c. (Jussi Kivilinna)
 237 + *
 238 + *             2008/08/06 - 2.6.26 - (JK)
 239 + *              - Replaced tasklet with 'netif_schedule()'.
 240 + *              - Cleaned up and added comments for imq_nf_queue().
 241 + *
 242 + *             2009/04/12
 243 + *              - Add skb_save_cb/skb_restore_cb helper functions for backuping
 244 + *                control buffer. This is needed because qdisc-layer on kernels
 245 + *                2.6.27 and newer overwrite control buffer. (Jussi Kivilinna)
 246 + *              - Add better locking for IMQ device. Hopefully this will solve
 247 + *                SMP issues. (Jussi Kivilinna)
 248 + *              - Port to 2.6.27
 249 + *              - Port to 2.6.28
 250 + *              - Port to 2.6.29 + fix rmmod not working
 251 + *
 252 + *             2009/04/20 - (Jussi Kivilinna)
 253 + *              - Use netdevice feature flags to avoid extra packet handling
 254 + *                by core networking layer and possibly increase performance.
 255 + *
 256 + *             2009/09/26 - (Jussi Kivilinna)
 257 + *              - Add imq_nf_reinject_lockless to fix deadlock with
 258 + *                imq_nf_queue/imq_nf_reinject.
 259 + *
 260 + *             2009/12/08 - (Jussi Kivilinna)
 261 + *              - Port to 2.6.32
 262 + *              - Add check for skb->nf_queue_entry==NULL in imq_dev_xmit()
 263 + *              - Also add better error checking for skb->nf_queue_entry usage
 264 + *
 265 + *             2010/02/25 - (Jussi Kivilinna)
 266 + *              - Port to 2.6.33
 267 + *
 268 + *             2010/08/15 - (Jussi Kivilinna)
 269 + *              - Port to 2.6.35
 270 + *              - Simplify hook registration by using nf_register_hooks.
 271 + *              - nf_reinject doesn't need spinlock around it, therefore remove
 272 + *                imq_nf_reinject function. Other nf_reinject users protect
 273 + *                their own data with spinlock. With IMQ however all data is
 274 + *                needed is stored per skbuff, so no locking is needed.
 275 + *              - Changed IMQ to use 'separate' NF_IMQ_QUEUE instead of
 276 + *                NF_QUEUE, this allows working coexistance of IMQ and other
 277 + *                NF_QUEUE users.
 278 + *              - Make IMQ multi-queue. Number of IMQ device queues can be
 279 + *                increased with 'numqueues' module parameters. Default number
 280 + *                of queues is 1, in other words by default IMQ works as
 281 + *                single-queue device. Multi-queue selection is based on
 282 + *                IFB multi-queue patch by Changli Gao <xiaosuo@gmail.com>.
 283 + *
 284 + *             2011/03/18 - (Jussi Kivilinna)
 285 + *              - Port to 2.6.38
 286 + *
 287 + *             2011/07/12 - (syoder89@gmail.com)
 288 + *              - Crash fix that happens when the receiving interface has more
 289 + *                than one queue (add missing skb_set_queue_mapping in
 290 + *                imq_select_queue).
 291 + *
 292 + *             2011/07/26 - (Jussi Kivilinna)
 293 + *              - Add queue mapping checks for packets exiting IMQ.
 294 + *              - Port to 3.0
 295 + *
 296 + *             2011/08/16 - (Jussi Kivilinna)
 297 + *              - Clear IFF_TX_SKB_SHARING flag that was added for linux 3.0.2
 298 + *
 299 + *             2011/11/03 - Germano Michel <germanomichel@gmail.com>
 300 + *              - Fix IMQ for net namespaces
 301 + *
 302 + *             2011/11/04 - Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
 303 + *              - Port to 3.1
 304 + *              - Clean-up, move 'get imq device pointer by imqX name' to
 305 + *                separate function from imq_nf_queue().
 306 + *
 307 + *             2012/01/05 - Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
 308 + *              - Port to 3.2
 309 + *
 310 + *             2012/03/19 - Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
 311 + *              - Port to 3.3
 312 + *
 313 + *             2012/12/12 - Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
 314 + *              - Port to 3.7
 315 + *              - Fix checkpatch.pl warnings
 316 + *
 317 + *             2013/09/10 - Jussi Kivilinna <jussi.kivilinna@iki.fi>
 318 + *              - Fixed GSO handling for 3.10, see imq_nf_queue() for comments.
 319 + *              - Don't copy skb->cb_next when copying or cloning skbuffs.
 320 + *
 321 + *            Also, many thanks to pablo Sebastian Greco for making the initial
 322 + *            patch and to those who helped the testing.
 323 + *
 324 + *             More info at: http://www.linuximq.net/ (Andre Correa)
 325 + */
 326 +
 327 +#include <linux/module.h>
 328 +#include <linux/kernel.h>
 329 +#include <linux/moduleparam.h>
 330 +#include <linux/list.h>
 331 +#include <linux/skbuff.h>
 332 +#include <linux/netdevice.h>
 333 +#include <linux/etherdevice.h>
 334 +#include <linux/rtnetlink.h>
 335 +#include <linux/if_arp.h>
 336 +#include <linux/netfilter.h>
 337 +#include <linux/netfilter_ipv4.h>
 338 +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 339 +       #include <linux/netfilter_ipv6.h>
 340 +#endif
 341 +#include <linux/imq.h>
 342 +#include <net/pkt_sched.h>
 343 +#include <net/netfilter/nf_queue.h>
 344 +#include <net/sock.h>
 345 +#include <linux/ip.h>
 346 +#include <linux/ipv6.h>
 347 +#include <linux/if_vlan.h>
 348 +#include <linux/if_pppox.h>
 349 +#include <net/ip.h>
 350 +#include <net/ipv6.h>
 351 +
 352 +static int imq_nf_queue(struct nf_queue_entry *entry, unsigned queue_num);
 353 +
 354 +static nf_hookfn imq_nf_hook;
 355 +
 356 +static struct nf_hook_ops imq_ops[] = {
 357 +       {
 358 +       /* imq_ingress_ipv4 */
 359 +               .hook           = imq_nf_hook,
 360 +               .owner          = THIS_MODULE,
 361 +               .pf             = PF_INET,
 362 +               .hooknum        = NF_INET_PRE_ROUTING,
 363 +#if defined(CONFIG_IMQ_BEHAVIOR_BA) || defined(CONFIG_IMQ_BEHAVIOR_BB)
 364 +               .priority       = NF_IP_PRI_MANGLE + 1,
 365 +#else
 366 +               .priority       = NF_IP_PRI_NAT_DST + 1,
 367 +#endif
 368 +       },
 369 +       {
 370 +       /* imq_egress_ipv4 */
 371 +               .hook           = imq_nf_hook,
 372 +               .owner          = THIS_MODULE,
 373 +               .pf             = PF_INET,
 374 +               .hooknum        = NF_INET_POST_ROUTING,
 375 +#if defined(CONFIG_IMQ_BEHAVIOR_AA) || defined(CONFIG_IMQ_BEHAVIOR_BA)
 376 +               .priority       = NF_IP_PRI_LAST,
 377 +#else
 378 +               .priority       = NF_IP_PRI_NAT_SRC - 1,
 379 +#endif
 380 +       },
 381 +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 382 +       {
 383 +       /* imq_ingress_ipv6 */
 384 +               .hook           = imq_nf_hook,
 385 +               .owner          = THIS_MODULE,
 386 +               .pf             = PF_INET6,
 387 +               .hooknum        = NF_INET_PRE_ROUTING,
 388 +#if defined(CONFIG_IMQ_BEHAVIOR_BA) || defined(CONFIG_IMQ_BEHAVIOR_BB)
 389 +               .priority       = NF_IP6_PRI_MANGLE + 1,
 390 +#else
 391 +               .priority       = NF_IP6_PRI_NAT_DST + 1,
 392 +#endif
 393 +       },
 394 +       {
 395 +       /* imq_egress_ipv6 */
 396 +               .hook           = imq_nf_hook,
 397 +               .owner          = THIS_MODULE,
 398 +               .pf             = PF_INET6,
 399 +               .hooknum        = NF_INET_POST_ROUTING,
 400 +#if defined(CONFIG_IMQ_BEHAVIOR_AA) || defined(CONFIG_IMQ_BEHAVIOR_BA)
 401 +               .priority       = NF_IP6_PRI_LAST,
 402 +#else
 403 +               .priority       = NF_IP6_PRI_NAT_SRC - 1,
 404 +#endif
 405 +       },
 406 +#endif
 407 +};
 408 +
 409 +#if defined(CONFIG_IMQ_NUM_DEVS)
 410 +static int numdevs = CONFIG_IMQ_NUM_DEVS;
 411 +#else
 412 +static int numdevs = IMQ_MAX_DEVS;
 413 +#endif
 414 +
 415 +static struct net_device *imq_devs_cache[IMQ_MAX_DEVS];
 416 +
 417 +#define IMQ_MAX_QUEUES 32
 418 +static int numqueues = 1;
 419 +static u32 imq_hashrnd;
 420 +
 421 +static inline __be16 pppoe_proto(const struct sk_buff *skb)
 422 +{
 423 +       return *((__be16 *)(skb_mac_header(skb) + ETH_HLEN +
 424 +                       sizeof(struct pppoe_hdr)));
 425 +}
 426 +
 427 +static u16 imq_hash(struct net_device *dev, struct sk_buff *skb)
 428 +{
 429 +       unsigned int pull_len;
 430 +       u16 protocol = skb->protocol;
 431 +       u32 addr1, addr2;
 432 +       u32 hash, ihl = 0;
 433 +       union {
 434 +               u16 in16[2];
 435 +               u32 in32;
 436 +       } ports;
 437 +       u8 ip_proto;
 438 +
 439 +       pull_len = 0;
 440 +
 441 +recheck:
 442 +       switch (protocol) {
 443 +       case htons(ETH_P_8021Q): {
 444 +               if (unlikely(skb_pull(skb, VLAN_HLEN) == NULL))
 445 +                       goto other;
 446 +
 447 +               pull_len += VLAN_HLEN;
 448 +               skb->network_header += VLAN_HLEN;
 449 +
 450 +               protocol = vlan_eth_hdr(skb)->h_vlan_encapsulated_proto;
 451 +               goto recheck;
 452 +       }
 453 +
 454 +       case htons(ETH_P_PPP_SES): {
 455 +               if (unlikely(skb_pull(skb, PPPOE_SES_HLEN) == NULL))
 456 +                       goto other;
 457 +
 458 +               pull_len += PPPOE_SES_HLEN;
 459 +               skb->network_header += PPPOE_SES_HLEN;
 460 +
 461 +               protocol = pppoe_proto(skb);
 462 +               goto recheck;
 463 +       }
 464 +
 465 +       case htons(ETH_P_IP): {
 466 +               const struct iphdr *iph = ip_hdr(skb);
 467 +
 468 +               if (unlikely(!pskb_may_pull(skb, sizeof(struct iphdr))))
 469 +                       goto other;
 470 +
 471 +               addr1 = iph->daddr;
 472 +               addr2 = iph->saddr;
 473 +
 474 +               ip_proto = !(ip_hdr(skb)->frag_off & htons(IP_MF | IP_OFFSET)) ?
 475 +                                iph->protocol : 0;
 476 +               ihl = ip_hdrlen(skb);
 477 +
 478 +               break;
 479 +       }
 480 +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 481 +       case htons(ETH_P_IPV6): {
 482 +               const struct ipv6hdr *iph = ipv6_hdr(skb);
 483 +               __be16 fo = 0;
 484 +
 485 +               if (unlikely(!pskb_may_pull(skb, sizeof(struct ipv6hdr))))
 486 +                       goto other;
 487 +
 488 +               addr1 = iph->daddr.s6_addr32[3];
 489 +               addr2 = iph->saddr.s6_addr32[3];
 490 +               ihl = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &ip_proto,
 491 +                                      &fo);
 492 +               if (unlikely(ihl < 0))
 493 +                       goto other;
 494 +
 495 +               break;
 496 +       }
 497 +#endif
 498 +       default:
 499 +other:
 500 +               if (pull_len != 0) {
 501 +                       skb_push(skb, pull_len);
 502 +                       skb->network_header -= pull_len;
 503 +               }
 504 +
 505 +               return (u16)(ntohs(protocol) % dev->real_num_tx_queues);
 506 +       }
 507 +
 508 +       if (addr1 > addr2)
 509 +               swap(addr1, addr2);
 510 +
 511 +       switch (ip_proto) {
 512 +       case IPPROTO_TCP:
 513 +       case IPPROTO_UDP:
 514 +       case IPPROTO_DCCP:
 515 +       case IPPROTO_ESP:
 516 +       case IPPROTO_AH:
 517 +       case IPPROTO_SCTP:
 518 +       case IPPROTO_UDPLITE: {
 519 +               if (likely(skb_copy_bits(skb, ihl, &ports.in32, 4) >= 0)) {
 520 +                       if (ports.in16[0] > ports.in16[1])
 521 +                               swap(ports.in16[0], ports.in16[1]);
 522 +                       break;
 523 +               }
 524 +               /* fall-through */
 525 +       }
 526 +       default:
 527 +               ports.in32 = 0;
 528 +               break;
 529 +       }
 530 +
 531 +       if (pull_len != 0) {
 532 +               skb_push(skb, pull_len);
 533 +               skb->network_header -= pull_len;
 534 +       }
 535 +
 536 +       hash = jhash_3words(addr1, addr2, ports.in32, imq_hashrnd ^ ip_proto);
 537 +
 538 +       return (u16)(((u64)hash * dev->real_num_tx_queues) >> 32);
 539 +}
 540 +
 541 +static inline bool sk_tx_queue_recorded(struct sock *sk)
 542 +{
 543 +       return (sk_tx_queue_get(sk) >= 0);
 544 +}
 545 +
 546 +static struct netdev_queue *imq_select_queue(struct net_device *dev,
 547 +                                               struct sk_buff *skb)
 548 +{
 549 +       u16 queue_index = 0;
 550 +       u32 hash;
 551 +
 552 +       if (likely(dev->real_num_tx_queues == 1))
 553 +               goto out;
 554 +
 555 +       /* IMQ can be receiving ingress or engress packets. */
 556 +
 557 +       /* Check first for if rx_queue is set */
 558 +       if (skb_rx_queue_recorded(skb)) {
 559 +               queue_index = skb_get_rx_queue(skb);
 560 +               goto out;
 561 +       }
 562 +
 563 +       /* Check if socket has tx_queue set */
 564 +       if (sk_tx_queue_recorded(skb->sk)) {
 565 +               queue_index = sk_tx_queue_get(skb->sk);
 566 +               goto out;
 567 +       }
 568 +
 569 +       /* Try use socket hash */
 570 +       if (skb->sk && skb->sk->sk_hash) {
 571 +               hash = skb->sk->sk_hash;
 572 +               queue_index =
 573 +                       (u16)(((u64)hash * dev->real_num_tx_queues) >> 32);
 574 +               goto out;
 575 +       }
 576 +
 577 +       /* Generate hash from packet data */
 578 +       queue_index = imq_hash(dev, skb);
 579 +
 580 +out:
 581 +       if (unlikely(queue_index >= dev->real_num_tx_queues))
 582 +               queue_index = (u16)((u32)queue_index % dev->real_num_tx_queues);
 583 +
 584 +       skb_set_queue_mapping(skb, queue_index);
 585 +       return netdev_get_tx_queue(dev, queue_index);
 586 +}
 587 +
 588 +static struct net_device_stats *imq_get_stats(struct net_device *dev)
 589 +{
 590 +       return &dev->stats;
 591 +}
 592 +
 593 +/* called for packets kfree'd in qdiscs at places other than enqueue */
 594 +static void imq_skb_destructor(struct sk_buff *skb)
 595 +{
 596 +       struct nf_queue_entry *entry = skb->nf_queue_entry;
 597 +
 598 +       skb->nf_queue_entry = NULL;
 599 +
 600 +       if (entry) {
 601 +               nf_queue_entry_release_refs(entry);
 602 +               kfree(entry);
 603 +       }
 604 +
 605 +       skb_restore_cb(skb); /* kfree backup */
 606 +}
 607 +
 608 +static void imq_done_check_queue_mapping(struct sk_buff *skb,
 609 +                                        struct net_device *dev)
 610 +{
 611 +       unsigned int queue_index;
 612 +
 613 +       /* Don't let queue_mapping be left too large after exiting IMQ */
 614 +       if (likely(skb->dev != dev && skb->dev != NULL)) {
 615 +               queue_index = skb_get_queue_mapping(skb);
 616 +               if (unlikely(queue_index >= skb->dev->real_num_tx_queues)) {
 617 +                       queue_index = (u16)((u32)queue_index %
 618 +                                               skb->dev->real_num_tx_queues);
 619 +                       skb_set_queue_mapping(skb, queue_index);
 620 +               }
 621 +       } else {
 622 +               /* skb->dev was IMQ device itself or NULL, be on safe side and
 623 +                * just clear queue mapping.
 624 +                */
 625 +               skb_set_queue_mapping(skb, 0);
 626 +       }
 627 +}
 628 +
 629 +static netdev_tx_t imq_dev_xmit(struct sk_buff *skb, struct net_device *dev)
 630 +{
 631 +       struct nf_queue_entry *entry = skb->nf_queue_entry;
 632 +
 633 +       skb->nf_queue_entry = NULL;
 634 +       dev->trans_start = jiffies;
 635 +
 636 +       dev->stats.tx_bytes += skb->len;
 637 +       dev->stats.tx_packets++;
 638 +
 639 +       if (unlikely(entry == NULL)) {
 640 +               /* We don't know what is going on here.. packet is queued for
 641 +                * imq device, but (probably) not by us.
 642 +                *
 643 +                * If this packet was not send here by imq_nf_queue(), then
 644 +                * skb_save_cb() was not used and skb_free() should not show:
 645 +                *   WARNING: IMQ: kfree_skb: skb->cb_next:..
 646 +                * and/or
 647 +                *   WARNING: IMQ: kfree_skb: skb->nf_queue_entry...
 648 +                *
 649 +                * However if this message is shown, then IMQ is somehow broken
 650 +                * and you should report this to linuximq.net.
 651 +                */
 652 +
 653 +               /* imq_dev_xmit is black hole that eats all packets, report that
 654 +                * we eat this packet happily and increase dropped counters.
 655 +                */
 656 +
 657 +               dev->stats.tx_dropped++;
 658 +               dev_kfree_skb(skb);
 659 +
 660 +               return NETDEV_TX_OK;
 661 +       }
 662 +
 663 +       skb_restore_cb(skb); /* restore skb->cb */
 664 +
 665 +       skb->imq_flags = 0;
 666 +       skb->destructor = NULL;
 667 +
 668 +       imq_done_check_queue_mapping(skb, dev);
 669 +
 670 +       nf_reinject(entry, NF_ACCEPT);
 671 +
 672 +       return NETDEV_TX_OK;
 673 +}
 674 +
 675 +static struct net_device *get_imq_device_by_index(int index)
 676 +{
 677 +       struct net_device *dev = NULL;
 678 +       struct net *net;
 679 +       char buf[8];
 680 +
 681 +       /* get device by name and cache result */
 682 +       snprintf(buf, sizeof(buf), "imq%d", index);
 683 +
 684 +       /* Search device from all namespaces. */
 685 +       for_each_net(net) {
 686 +               dev = dev_get_by_name(net, buf);
 687 +               if (dev)
 688 +                       break;
 689 +       }
 690 +
 691 +       if (WARN_ON_ONCE(dev == NULL)) {
 692 +               /* IMQ device not found. Exotic config? */
 693 +               return ERR_PTR(-ENODEV);
 694 +       }
 695 +
 696 +       imq_devs_cache[index] = dev;
 697 +       dev_put(dev);
 698 +
 699 +       return dev;
 700 +}
 701 +
 702 +static struct nf_queue_entry *nf_queue_entry_dup(struct nf_queue_entry *e)
 703 +{
 704 +       struct nf_queue_entry *entry = kmemdup(e, e->size, GFP_ATOMIC);
 705 +       if (entry) {
 706 +               if (nf_queue_entry_get_refs(entry))
 707 +                       return entry;
 708 +               kfree(entry);
 709 +       }
 710 +       return NULL;
 711 +}
 712 +
 713 +#ifdef CONFIG_BRIDGE_NETFILTER
 714 +/* When called from bridge netfilter, skb->data must point to MAC header
 715 + * before calling skb_gso_segment(). Else, original MAC header is lost
 716 + * and segmented skbs will be sent to wrong destination.
 717 + */
 718 +static void nf_bridge_adjust_skb_data(struct sk_buff *skb)
 719 +{
 720 +       if (skb->nf_bridge)
 721 +               __skb_push(skb, skb->network_header - skb->mac_header);
 722 +}
 723 +
 724 +static void nf_bridge_adjust_segmented_data(struct sk_buff *skb)
 725 +{
 726 +       if (skb->nf_bridge)
 727 +               __skb_pull(skb, skb->network_header - skb->mac_header);
 728 +}
 729 +#else
 730 +#define nf_bridge_adjust_skb_data(s) do {} while (0)
 731 +#define nf_bridge_adjust_segmented_data(s) do {} while (0)
 732 +#endif
 733 +
 734 +static void free_entry(struct nf_queue_entry *entry)
 735 +{
 736 +       nf_queue_entry_release_refs(entry);
 737 +       kfree(entry);
 738 +}
 739 +
 740 +static int __imq_nf_queue(struct nf_queue_entry *entry, struct net_device *dev);
 741 +
 742 +static int __imq_nf_queue_gso(struct nf_queue_entry *entry,
 743 +                             struct net_device *dev, struct sk_buff *skb)
 744 +{
 745 +       int ret = -ENOMEM;
 746 +       struct nf_queue_entry *entry_seg;
 747 +
 748 +       nf_bridge_adjust_segmented_data(skb);
 749 +
 750 +       if (skb->next == NULL) { /* last packet, no need to copy entry */
 751 +               struct sk_buff *gso_skb = entry->skb;
 752 +               entry->skb = skb;
 753 +               ret = __imq_nf_queue(entry, dev);
 754 +               if (ret)
 755 +                       entry->skb = gso_skb;
 756 +               return ret;
 757 +       }
 758 +
 759 +       skb->next = NULL;
 760 +
 761 +       entry_seg = nf_queue_entry_dup(entry);
 762 +       if (entry_seg) {
 763 +               entry_seg->skb = skb;
 764 +               ret = __imq_nf_queue(entry_seg, dev);
 765 +               if (ret)
 766 +                       free_entry(entry_seg);
 767 +       }
 768 +       return ret;
 769 +}
 770 +
 771 +static int imq_nf_queue(struct nf_queue_entry *entry, unsigned queue_num)
 772 +{
 773 +       struct sk_buff *skb, *segs;
 774 +       struct net_device *dev;
 775 +       unsigned int queued;
 776 +       int index, retval, err;
 777 +
 778 +       index = entry->skb->imq_flags & IMQ_F_IFMASK;
 779 +       if (unlikely(index > numdevs - 1)) {
 780 +               if (net_ratelimit())
 781 +                       pr_warn("IMQ: invalid device specified, highest is %u\n",
 782 +                               numdevs - 1);
 783 +               retval = -EINVAL;
 784 +               goto out_no_dev;
 785 +       }
 786 +
 787 +       /* check for imq device by index from cache */
 788 +       dev = imq_devs_cache[index];
 789 +       if (unlikely(!dev)) {
 790 +               dev = get_imq_device_by_index(index);
 791 +               if (IS_ERR(dev)) {
 792 +                       retval = PTR_ERR(dev);
 793 +                       goto out_no_dev;
 794 +               }
 795 +       }
 796 +
 797 +       if (unlikely(!(dev->flags & IFF_UP))) {
 798 +               entry->skb->imq_flags = 0;
 799 +               retval = -ECANCELED;
 800 +               goto out_no_dev;
 801 +       }
 802 +
 803 +       if (!skb_is_gso(entry->skb))
 804 +               return __imq_nf_queue(entry, dev);
 805 +
 806 +       /* Since 3.10.x, GSO handling moved here as result of upstream commit
 807 +        * a5fedd43d5f6c94c71053a66e4c3d2e35f1731a2 (netfilter: move
 808 +        * skb_gso_segment into nfnetlink_queue module).
 809 +        *
 810 +        * Following code replicates the gso handling from
 811 +        * 'net/netfilter/nfnetlink_queue_core.c':nfqnl_enqueue_packet().
 812 +        */
 813 +
 814 +       skb = entry->skb;
 815 +
 816 +       switch (entry->pf) {
 817 +       case NFPROTO_IPV4:
 818 +               skb->protocol = htons(ETH_P_IP);
 819 +               break;
 820 +       case NFPROTO_IPV6:
 821 +               skb->protocol = htons(ETH_P_IPV6);
 822 +               break;
 823 +       }
 824 +
 825 +       nf_bridge_adjust_skb_data(skb);
 826 +       segs = skb_gso_segment(skb, 0);
 827 +       /* Does not use PTR_ERR to limit the number of error codes that can be
 828 +        * returned by nf_queue.  For instance, callers rely on -ECANCELED to
 829 +        * mean 'ignore this hook'.
 830 +        */
 831 +       err = -ENOBUFS;
 832 +       if (IS_ERR(segs))
 833 +               goto out_err;
 834 +       queued = 0;
 835 +       err = 0;
 836 +       do {
 837 +               struct sk_buff *nskb = segs->next;
 838 +               if (nskb && nskb->next)
 839 +                       nskb->cb_next = NULL;
 840 +               if (err == 0)
 841 +                       err = __imq_nf_queue_gso(entry, dev, segs);
 842 +               if (err == 0)
 843 +                       queued++;
 844 +               else
 845 +                       kfree_skb(segs);
 846 +               segs = nskb;
 847 +       } while (segs);
 848 +
 849 +       if (queued) {
 850 +               if (err) /* some segments are already queued */
 851 +                       free_entry(entry);
 852 +               kfree_skb(skb);
 853 +               return 0;
 854 +       }
 855 +
 856 +out_err:
 857 +       nf_bridge_adjust_segmented_data(skb);
 858 +       retval = err;
 859 +out_no_dev:
 860 +       return retval;
 861 +}
 862 +
 863 +static int __imq_nf_queue(struct nf_queue_entry *entry, struct net_device *dev)
 864 +{
 865 +       struct sk_buff *skb_orig, *skb, *skb_shared;
 866 +       struct Qdisc *q;
 867 +       struct netdev_queue *txq;
 868 +       spinlock_t *root_lock;
 869 +       int users;
 870 +       int retval = -EINVAL;
 871 +       unsigned int orig_queue_index;
 872 +
 873 +       dev->last_rx = jiffies;
 874 +
 875 +       skb = entry->skb;
 876 +       skb_orig = NULL;
 877 +
 878 +       /* skb has owner? => make clone */
 879 +       if (unlikely(skb->destructor)) {
 880 +               skb_orig = skb;
 881 +               skb = skb_clone(skb, GFP_ATOMIC);
 882 +               if (unlikely(!skb)) {
 883 +                       retval = -ENOMEM;
 884 +                       goto out;
 885 +               }
 886 +               skb->cb_next = NULL;
 887 +               entry->skb = skb;
 888 +       }
 889 +
 890 +       skb->nf_queue_entry = entry;
 891 +
 892 +       dev->stats.rx_bytes += skb->len;
 893 +       dev->stats.rx_packets++;
 894 +
 895 +       if (!skb->dev) {
 896 +               /* skb->dev == NULL causes problems, try the find cause. */
 897 +               if (net_ratelimit()) {
 898 +                       dev_warn(&dev->dev,
 899 +                                "received packet with skb->dev == NULL\n");
 900 +                       dump_stack();
 901 +               }
 902 +
 903 +               skb->dev = dev;
 904 +       }
 905 +
 906 +       /* Disables softirqs for lock below */
 907 +       rcu_read_lock_bh();
 908 +
 909 +       /* Multi-queue selection */
 910 +       orig_queue_index = skb_get_queue_mapping(skb);
 911 +       txq = imq_select_queue(dev, skb);
 912 +
 913 +       q = rcu_dereference(txq->qdisc);
 914 +       if (unlikely(!q->enqueue))
 915 +               goto packet_not_eaten_by_imq_dev;
 916 +
 917 +       root_lock = qdisc_lock(q);
 918 +       spin_lock(root_lock);
 919 +
 920 +       users = atomic_read(&skb->users);
 921 +
 922 +       skb_shared = skb_get(skb); /* increase reference count by one */
 923 +
 924 +       /* backup skb->cb, as qdisc layer will overwrite it */
 925 +       skb_save_cb(skb_shared);
 926 +       qdisc_enqueue_root(skb_shared, q); /* might kfree_skb */
 927 +
 928 +       if (likely(atomic_read(&skb_shared->users) == users + 1)) {
 929 +               kfree_skb(skb_shared); /* decrease reference count by one */
 930 +
 931 +               skb->destructor = &imq_skb_destructor;
 932 +
 933 +               /* cloned? */
 934 +               if (unlikely(skb_orig))
 935 +                       kfree_skb(skb_orig); /* free original */
 936 +
 937 +               spin_unlock(root_lock);
 938 +               rcu_read_unlock_bh();
 939 +
 940 +               /* schedule qdisc dequeue */
 941 +               __netif_schedule(q);
 942 +
 943 +               retval = 0;
 944 +               goto out;
 945 +       } else {
 946 +               skb_restore_cb(skb_shared); /* restore skb->cb */
 947 +               skb->nf_queue_entry = NULL;
 948 +               /*
 949 +                * qdisc dropped packet and decreased skb reference count of
 950 +                * skb, so we don't really want to and try refree as that would
 951 +                * actually destroy the skb.
 952 +                */
 953 +               spin_unlock(root_lock);
 954 +               goto packet_not_eaten_by_imq_dev;
 955 +       }
 956 +
 957 +packet_not_eaten_by_imq_dev:
 958 +       skb_set_queue_mapping(skb, orig_queue_index);
 959 +       rcu_read_unlock_bh();
 960 +
 961 +       /* cloned? restore original */
 962 +       if (unlikely(skb_orig)) {
 963 +               kfree_skb(skb);
 964 +               entry->skb = skb_orig;
 965 +       }
 966 +       retval = -1;
 967 +out:
 968 +       return retval;
 969 +}
 970 +
 971 +static unsigned int imq_nf_hook(unsigned int hook, struct sk_buff *pskb,
 972 +                               const struct net_device *indev,
 973 +                               const struct net_device *outdev,
 974 +                               int (*okfn)(struct sk_buff *))
 975 +{
 976 +       return (pskb->imq_flags & IMQ_F_ENQUEUE) ? NF_IMQ_QUEUE : NF_ACCEPT;
 977 +}
 978 +
 979 +static int imq_close(struct net_device *dev)
 980 +{
 981 +       netif_stop_queue(dev);
 982 +       return 0;
 983 +}
 984 +
 985 +static int imq_open(struct net_device *dev)
 986 +{
 987 +       netif_start_queue(dev);
 988 +       return 0;
 989 +}
 990 +
 991 +static const struct net_device_ops imq_netdev_ops = {
 992 +       .ndo_open               = imq_open,
 993 +       .ndo_stop               = imq_close,
 994 +       .ndo_start_xmit         = imq_dev_xmit,
 995 +       .ndo_get_stats          = imq_get_stats,
 996 +};
 997 +
 998 +static void imq_setup(struct net_device *dev)
 999 +{
1000 +       dev->netdev_ops         = &imq_netdev_ops;
1001 +       dev->type               = ARPHRD_VOID;
1002 +       dev->mtu                = 16000; /* too small? */
1003 +       dev->tx_queue_len       = 11000; /* too big? */
1004 +       dev->flags              = IFF_NOARP;
1005 +       dev->features           = NETIF_F_SG | NETIF_F_FRAGLIST |
1006 +                                 NETIF_F_GSO | NETIF_F_HW_CSUM |
1007 +                                 NETIF_F_HIGHDMA;
1008 +       dev->priv_flags         &= ~(IFF_XMIT_DST_RELEASE |
1009 +                                    IFF_TX_SKB_SHARING);
1010 +}
1011 +
1012 +static int imq_validate(struct nlattr *tb[], struct nlattr *data[])
1013 +{
1014 +       int ret = 0;
1015 +
1016 +       if (tb[IFLA_ADDRESS]) {
1017 +               if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) {
1018 +                       ret = -EINVAL;
1019 +                       goto end;
1020 +               }
1021 +               if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) {
1022 +                       ret = -EADDRNOTAVAIL;
1023 +                       goto end;
1024 +               }
1025 +       }
1026 +       return 0;
1027 +end:
1028 +       pr_warn("IMQ: imq_validate failed (%d)\n", ret);
1029 +       return ret;
1030 +}
1031 +
1032 +static struct rtnl_link_ops imq_link_ops __read_mostly = {
1033 +       .kind           = "imq",
1034 +       .priv_size      = 0,
1035 +       .setup          = imq_setup,
1036 +       .validate       = imq_validate,
1037 +};
1038 +
1039 +static const struct nf_queue_handler imq_nfqh = {
1040 +       .outfn = imq_nf_queue,
1041 +};
1042 +
1043 +static int __init imq_init_hooks(void)
1044 +{
1045 +       int ret;
1046 +
1047 +       nf_register_queue_imq_handler(&imq_nfqh);
1048 +
1049 +       ret = nf_register_hooks(imq_ops, ARRAY_SIZE(imq_ops));
1050 +       if (ret < 0)
1051 +               nf_unregister_queue_imq_handler();
1052 +
1053 +       return ret;
1054 +}
1055 +
1056 +static int __init imq_init_one(int index)
1057 +{
1058 +       struct net_device *dev;
1059 +       int ret;
1060 +
1061 +       dev = alloc_netdev_mq(0, "imq%d", imq_setup, numqueues);
1062 +       if (!dev)
1063 +               return -ENOMEM;
1064 +
1065 +       ret = dev_alloc_name(dev, dev->name);
1066 +       if (ret < 0)
1067 +               goto fail;
1068 +
1069 +       dev->rtnl_link_ops = &imq_link_ops;
1070 +       ret = register_netdevice(dev);
1071 +       if (ret < 0)
1072 +               goto fail;
1073 +
1074 +       return 0;
1075 +fail:
1076 +       free_netdev(dev);
1077 +       return ret;
1078 +}
1079 +
1080 +static int __init imq_init_devs(void)
1081 +{
1082 +       int err, i;
1083 +
1084 +       if (numdevs < 1 || numdevs > IMQ_MAX_DEVS) {
1085 +               pr_err("IMQ: numdevs has to be betweed 1 and %u\n",
1086 +                      IMQ_MAX_DEVS);
1087 +               return -EINVAL;
1088 +       }
1089 +
1090 +       if (numqueues < 1 || numqueues > IMQ_MAX_QUEUES) {
1091 +               pr_err("IMQ: numqueues has to be betweed 1 and %u\n",
1092 +                      IMQ_MAX_QUEUES);
1093 +               return -EINVAL;
1094 +       }
1095 +
1096 +       get_random_bytes(&imq_hashrnd, sizeof(imq_hashrnd));
1097 +
1098 +       rtnl_lock();
1099 +       err = __rtnl_link_register(&imq_link_ops);
1100 +
1101 +       for (i = 0; i < numdevs && !err; i++)
1102 +               err = imq_init_one(i);
1103 +
1104 +       if (err) {
1105 +               __rtnl_link_unregister(&imq_link_ops);
1106 +               memset(imq_devs_cache, 0, sizeof(imq_devs_cache));
1107 +       }
1108 +       rtnl_unlock();
1109 +
1110 +       return err;
1111 +}
1112 +
1113 +static int __init imq_init_module(void)
1114 +{
1115 +       int err;
1116 +
1117 +#if defined(CONFIG_IMQ_NUM_DEVS)
1118 +       BUILD_BUG_ON(CONFIG_IMQ_NUM_DEVS > 16);
1119 +       BUILD_BUG_ON(CONFIG_IMQ_NUM_DEVS < 2);
1120 +       BUILD_BUG_ON(CONFIG_IMQ_NUM_DEVS - 1 > IMQ_F_IFMASK);
1121 +#endif
1122 +
1123 +       err = imq_init_devs();
1124 +       if (err) {
1125 +               pr_err("IMQ: Error trying imq_init_devs(net)\n");
1126 +               return err;
1127 +       }
1128 +
1129 +       err = imq_init_hooks();
1130 +       if (err) {
1131 +               pr_err(KERN_ERR "IMQ: Error trying imq_init_hooks()\n");
1132 +               rtnl_link_unregister(&imq_link_ops);
1133 +               memset(imq_devs_cache, 0, sizeof(imq_devs_cache));
1134 +               return err;
1135 +       }
1136 +
1137 +       pr_info("IMQ driver loaded successfully. (numdevs = %d, numqueues = %d)\n",
1138 +               numdevs, numqueues);
1139 +
1140 +#if defined(CONFIG_IMQ_BEHAVIOR_BA) || defined(CONFIG_IMQ_BEHAVIOR_BB)
1141 +       pr_info("\tHooking IMQ before NAT on PREROUTING.\n");
1142 +#else
1143 +       pr_info("\tHooking IMQ after NAT on PREROUTING.\n");
1144 +#endif
1145 +#if defined(CONFIG_IMQ_BEHAVIOR_AB) || defined(CONFIG_IMQ_BEHAVIOR_BB)
1146 +       pr_info("\tHooking IMQ before NAT on POSTROUTING.\n");
1147 +#else
1148 +       pr_info("\tHooking IMQ after NAT on POSTROUTING.\n");
1149 +#endif
1150 +
1151 +       return 0;
1152 +}
1153 +
1154 +static void __exit imq_unhook(void)
1155 +{
1156 +       nf_unregister_hooks(imq_ops, ARRAY_SIZE(imq_ops));
1157 +       nf_unregister_queue_imq_handler();
1158 +}
1159 +
1160 +static void __exit imq_cleanup_devs(void)
1161 +{
1162 +       rtnl_link_unregister(&imq_link_ops);
1163 +       memset(imq_devs_cache, 0, sizeof(imq_devs_cache));
1164 +}
1165 +
1166 +static void __exit imq_exit_module(void)
1167 +{
1168 +       imq_unhook();
1169 +       imq_cleanup_devs();
1170 +       pr_info("IMQ driver unloaded successfully.\n");
1171 +}
1172 +
1173 +module_init(imq_init_module);
1174 +module_exit(imq_exit_module);
1175 +
1176 +module_param(numdevs, int, 0);
1177 +module_param(numqueues, int, 0);
1178 +MODULE_PARM_DESC(numdevs, "number of IMQ devices (how many imq* devices will be created)");
1179 +MODULE_PARM_DESC(numqueues, "number of queues per IMQ device");
1180 +MODULE_AUTHOR("http://www.linuximq.net");
1181 +MODULE_DESCRIPTION("Pseudo-driver for the intermediate queue device. See http://www.linuximq.net/ for more information.");
1182 +MODULE_LICENSE("GPL");
1183 +MODULE_ALIAS_RTNL_LINK("imq");
1184 +
1185 diff --git a/include/linux/imq.h b/include/linux/imq.h
1186 new file mode 100644
1187 index 0000000..1babb09
1188 --- /dev/null
1189 +++ b/include/linux/imq.h
1190 @@ -0,0 +1,13 @@
1191 +#ifndef _IMQ_H
1192 +#define _IMQ_H
1193 +
1194 +/* IFMASK (16 device indexes, 0 to 15) and flag(s) fit in 5 bits */
1195 +#define IMQ_F_BITS     5
1196 +
1197 +#define IMQ_F_IFMASK   0x0f
1198 +#define IMQ_F_ENQUEUE  0x10
1199 +
1200 +#define IMQ_MAX_DEVS   (IMQ_F_IFMASK + 1)
1201 +
1202 +#endif /* _IMQ_H */
1203 +
1204 diff --git a/include/linux/netfilter/xt_IMQ.h b/include/linux/netfilter/xt_IMQ.h
1205 new file mode 100644
1206 index 0000000..9b07230
1207 --- /dev/null
1208 +++ b/include/linux/netfilter/xt_IMQ.h
1209 @@ -0,0 +1,9 @@
1210 +#ifndef _XT_IMQ_H
1211 +#define _XT_IMQ_H
1212 +
1213 +struct xt_imq_info {
1214 +       unsigned int todev;     /* target imq device */
1215 +};
1216 +
1217 +#endif /* _XT_IMQ_H */
1218 +
1219 diff --git a/include/linux/netfilter_ipv4/ipt_IMQ.h b/include/linux/netfilter_ipv4/ipt_IMQ.h
1220 new file mode 100644
1221 index 0000000..7af320f
1222 --- /dev/null
1223 +++ b/include/linux/netfilter_ipv4/ipt_IMQ.h
1224 @@ -0,0 +1,10 @@
1225 +#ifndef _IPT_IMQ_H
1226 +#define _IPT_IMQ_H
1227 +
1228 +/* Backwards compatibility for old userspace */
1229 +#include <linux/netfilter/xt_IMQ.h>
1230 +
1231 +#define ipt_imq_info xt_imq_info
1232 +
1233 +#endif /* _IPT_IMQ_H */
1234 +
1235 diff --git a/include/linux/netfilter_ipv6/ip6t_IMQ.h b/include/linux/netfilter_ipv6/ip6t_IMQ.h
1236 new file mode 100644
1237 index 0000000..198ac01
1238 --- /dev/null
1239 +++ b/include/linux/netfilter_ipv6/ip6t_IMQ.h
1240 @@ -0,0 +1,10 @@
1241 +#ifndef _IP6T_IMQ_H
1242 +#define _IP6T_IMQ_H
1243 +
1244 +/* Backwards compatibility for old userspace */
1245 +#include <linux/netfilter/xt_IMQ.h>
1246 +
1247 +#define ip6t_imq_info xt_imq_info
1248 +
1249 +#endif /* _IP6T_IMQ_H */
1250 +
1251 diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
1252 index dec1748..1f17280 100644
1253 --- a/include/linux/skbuff.h
1254 +++ b/include/linux/skbuff.h
1255 @@ -33,6 +33,9 @@
1256  #include <linux/dma-mapping.h>
1257  #include <linux/netdev_features.h>
1258  #include <net/flow_keys.h>
1259 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1260 +#include <linux/imq.h>
1261 +#endif
1262
1263  /* Don't change this without changing skb_csum_unnecessary! */
1264  #define CHECKSUM_NONE 0
1265 @@ -420,6 +423,9 @@ struct sk_buff {
1266          * first. This is owned by whoever has the skb queued ATM.
1267          */
1268         char                    cb[48] __aligned(8);
1269 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1270 +       void                    *cb_next;
1271 +#endif
1272
1273         unsigned long           _skb_refdst;
1274  #ifdef CONFIG_XFRM
1275 @@ -458,6 +464,9 @@ struct sk_buff {
1276  #ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
1277         struct sk_buff          *nfct_reasm;
1278  #endif
1279 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1280 +       struct nf_queue_entry   *nf_queue_entry;
1281 +#endif
1282  #ifdef CONFIG_BRIDGE_NETFILTER
1283         struct nf_bridge_info   *nf_bridge;
1284  #endif
1285 @@ -497,6 +506,10 @@ struct sk_buff {
1286         /* 7/9 bit hole (depending on ndisc_nodetype presence) */
1287         kmemcheck_bitfield_end(flags2);
1288
1289 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1290 +       __u8                    imq_flags:IMQ_F_BITS;
1291 +#endif
1292 +
1293  #ifdef CONFIG_NET_DMA
1294         dma_cookie_t            dma_cookie;
1295  #endif
1296 @@ -626,6 +639,12 @@ static inline struct rtable *skb_rtable(const struct sk_buff *skb)
1297         return (struct rtable *)skb_dst(skb);
1298  }
1299
1300 +
1301 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1302 +extern int skb_save_cb(struct sk_buff *skb);
1303 +extern int skb_restore_cb(struct sk_buff *skb);
1304 +#endif
1305 +
1306  extern void kfree_skb(struct sk_buff *skb);
1307  extern void kfree_skb_list(struct sk_buff *segs);
1308  extern void skb_tx_error(struct sk_buff *skb);
1309 @@ -2754,6 +2773,10 @@ static inline void __nf_copy(struct sk_buff *dst, const struct sk_buff *src)
1310         dst->nfct_reasm = src->nfct_reasm;
1311         nf_conntrack_get_reasm(src->nfct_reasm);
1312  #endif
1313 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1314 +       dst->imq_flags = src->imq_flags;
1315 +       dst->nf_queue_entry = src->nf_queue_entry;
1316 +#endif
1317  #ifdef CONFIG_BRIDGE_NETFILTER
1318         dst->nf_bridge  = src->nf_bridge;
1319         nf_bridge_get(src->nf_bridge);
1320 diff --git a/include/net/netfilter/nf_queue.h b/include/net/netfilter/nf_queue.h
1321 index aaba4bb..f6e92a4 100644
1322 --- a/include/net/netfilter/nf_queue.h
1323 +++ b/include/net/netfilter/nf_queue.h
1324 @@ -29,6 +29,12 @@ struct nf_queue_handler {
1325  void nf_register_queue_handler(const struct nf_queue_handler *qh);
1326  void nf_unregister_queue_handler(void);
1327  extern void nf_reinject(struct nf_queue_entry *entry, unsigned int verdict);
1328 +extern void nf_queue_entry_release_refs(struct nf_queue_entry *entry);
1329 +
1330 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1331 +extern void nf_register_queue_imq_handler(const struct nf_queue_handler *qh);
1332 +extern void nf_unregister_queue_imq_handler(void);
1333 +#endif
1334
1335  bool nf_queue_entry_get_refs(struct nf_queue_entry *entry);
1336  void nf_queue_entry_release_refs(struct nf_queue_entry *entry);
1337 diff --git a/include/uapi/linux/netfilter.h b/include/uapi/linux/netfilter.h
1338 index f7dc0eb..58c46a9 100644
1339 --- a/include/uapi/linux/netfilter.h
1340 +++ b/include/uapi/linux/netfilter.h
1341 @@ -13,7 +13,8 @@
1342  #define NF_QUEUE 3
1343  #define NF_REPEAT 4
1344  #define NF_STOP 5
1345 -#define NF_MAX_VERDICT NF_STOP
1346 +#define NF_IMQ_QUEUE 6
1347 +#define NF_MAX_VERDICT NF_IMQ_QUEUE
1348
1349  /* we overload the higher bits for encoding auxiliary data such as the queue
1350   * number or errno values. Not nice, but better than additional function
1351 diff --git a/net/core/dev.c b/net/core/dev.c
1352 index 7ddbb31..125b7b9 100644
1353 --- a/net/core/dev.c
1354 +++ b/net/core/dev.c
1355 @@ -129,6 +129,9 @@
1356  #include <linux/inetdevice.h>
1357  #include <linux/cpu_rmap.h>
1358  #include <linux/static_key.h>
1359 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1360 +#include <linux/imq.h>
1361 +#endif
1362
1363  #include "net-sysfs.h"
1364
1365 @@ -2573,7 +2576,12 @@ int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
1366                         }
1367                 }
1368
1369 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1370 +               if (!list_empty(&ptype_all) &&
1371 +                                       !(skb->imq_flags & IMQ_F_ENQUEUE))
1372 +#else
1373                 if (!list_empty(&ptype_all))
1374 +#endif
1375                         dev_queue_xmit_nit(skb, dev);
1376
1377                 skb_len = skb->len;
1378 diff --git a/net/core/skbuff.c b/net/core/skbuff.c
1379 index 1c1738c..5d1b75b 100644
1380 --- a/net/core/skbuff.c
1381 +++ b/net/core/skbuff.c
1382 @@ -73,6 +73,9 @@
1383
1384  struct kmem_cache *skbuff_head_cache __read_mostly;
1385  static struct kmem_cache *skbuff_fclone_cache __read_mostly;
1386 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1387 +static struct kmem_cache *skbuff_cb_store_cache __read_mostly;
1388 +#endif
1389
1390  static void sock_pipe_buf_release(struct pipe_inode_info *pipe,
1391                                   struct pipe_buffer *buf)
1392 @@ -92,6 +95,82 @@ static int sock_pipe_buf_steal(struct pipe_inode_info *pipe,
1393         return 1;
1394  }
1395
1396 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1397 +/* Control buffer save/restore for IMQ devices */
1398 +struct skb_cb_table {
1399 +       char                    cb[48] __aligned(8);
1400 +       void                    *cb_next;
1401 +       atomic_t                refcnt;
1402 +};
1403 +
1404 +static DEFINE_SPINLOCK(skb_cb_store_lock);
1405 +
1406 +int skb_save_cb(struct sk_buff *skb)
1407 +{
1408 +       struct skb_cb_table *next;
1409 +
1410 +       next = kmem_cache_alloc(skbuff_cb_store_cache, GFP_ATOMIC);
1411 +       if (!next)
1412 +               return -ENOMEM;
1413 +
1414 +       BUILD_BUG_ON(sizeof(skb->cb) != sizeof(next->cb));
1415 +
1416 +       memcpy(next->cb, skb->cb, sizeof(skb->cb));
1417 +       next->cb_next = skb->cb_next;
1418 +
1419 +       atomic_set(&next->refcnt, 1);
1420 +
1421 +       skb->cb_next = next;
1422 +       return 0;
1423 +}
1424 +EXPORT_SYMBOL(skb_save_cb);
1425 +
1426 +int skb_restore_cb(struct sk_buff *skb)
1427 +{
1428 +       struct skb_cb_table *next;
1429 +
1430 +       if (!skb->cb_next)
1431 +               return 0;
1432 +
1433 +       next = skb->cb_next;
1434 +
1435 +       BUILD_BUG_ON(sizeof(skb->cb) != sizeof(next->cb));
1436 +
1437 +       memcpy(skb->cb, next->cb, sizeof(skb->cb));
1438 +       skb->cb_next = next->cb_next;
1439 +
1440 +       spin_lock(&skb_cb_store_lock);
1441 +
1442 +       if (atomic_dec_and_test(&next->refcnt))
1443 +               kmem_cache_free(skbuff_cb_store_cache, next);
1444 +
1445 +       spin_unlock(&skb_cb_store_lock);
1446 +
1447 +       return 0;
1448 +}
1449 +EXPORT_SYMBOL(skb_restore_cb);
1450 +
1451 +static void skb_copy_stored_cb(struct sk_buff *new, const struct sk_buff *__old)
1452 +{
1453 +       struct skb_cb_table *next;
1454 +       struct sk_buff *old;
1455 +
1456 +       if (!__old->cb_next) {
1457 +               new->cb_next = NULL;
1458 +               return;
1459 +       }
1460 +
1461 +       spin_lock(&skb_cb_store_lock);
1462 +
1463 +       old = (struct sk_buff *)__old;
1464 +
1465 +       next = old->cb_next;
1466 +       atomic_inc(&next->refcnt);
1467 +       new->cb_next = next;
1468 +
1469 +       spin_unlock(&skb_cb_store_lock);
1470 +}
1471 +#endif
1472
1473  /* Pipe buffer operations for a socket. */
1474  static const struct pipe_buf_operations sock_pipe_buf_ops = {
1475 @@ -582,6 +661,28 @@ static void skb_release_head_state(struct sk_buff *skb)
1476                 WARN_ON(in_irq());
1477                 skb->destructor(skb);
1478         }
1479 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1480 +       /*
1481 +        * This should not happen. When it does, avoid memleak by restoring
1482 +        * the chain of cb-backups.
1483 +        */
1484 +       while (skb->cb_next != NULL) {
1485 +               if (net_ratelimit())
1486 +                       pr_warn("IMQ: kfree_skb: skb->cb_next: %08x\n",
1487 +                               (unsigned int)skb->cb_next);
1488 +
1489 +               skb_restore_cb(skb);
1490 +       }
1491 +       /*
1492 +        * This should not happen either, nf_queue_entry is nullified in
1493 +        * imq_dev_xmit(). If we have non-NULL nf_queue_entry then we are
1494 +        * leaking entry pointers, maybe memory. We don't know if this is
1495 +        * pointer to already freed memory, or should this be freed.
1496 +        * If this happens we need to add refcounting, etc for nf_queue_entry.
1497 +        */
1498 +       if (skb->nf_queue_entry && net_ratelimit())
1499 +               pr_warn("%s\n", "IMQ: kfree_skb: skb->nf_queue_entry != NULL");
1500 +#endif
1501  #if IS_ENABLED(CONFIG_NF_CONNTRACK)
1502         nf_conntrack_put(skb->nfct);
1503  #endif
1504 @@ -716,6 +817,10 @@ static void __copy_skb_header(struct sk_buff *new, const struct sk_buff *old)
1505         new->sp                 = secpath_get(old->sp);
1506  #endif
1507         memcpy(new->cb, old->cb, sizeof(old->cb));
1508 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1509 +       new->cb_next = NULL;
1510 +       /*skb_copy_stored_cb(new, old);*/
1511 +#endif
1512         new->csum               = old->csum;
1513         new->local_df           = old->local_df;
1514         new->pkt_type           = old->pkt_type;
1515 @@ -3095,6 +3200,13 @@ void __init skb_init(void)
1516                                                 0,
1517                                                 SLAB_HWCACHE_ALIGN|SLAB_PANIC,
1518                                                 NULL);
1519 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1520 +       skbuff_cb_store_cache = kmem_cache_create("skbuff_cb_store_cache",
1521 +                                                 sizeof(struct skb_cb_table),
1522 +                                                 0,
1523 +                                                 SLAB_HWCACHE_ALIGN|SLAB_PANIC,
1524 +                                                 NULL);
1525 +#endif
1526  }
1527
1528  /**
1529 diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
1530 index 6e3ddf8..ddae387 100644
1531 --- a/net/ipv6/ip6_output.c
1532 +++ b/net/ipv6/ip6_output.c
1533 @@ -89,9 +89,6 @@ static int ip6_finish_output2(struct sk_buff *skb)
1534         struct in6_addr *nexthop;
1535         int ret;
1536
1537 -       skb->protocol = htons(ETH_P_IPV6);
1538 -       skb->dev = dev;
1539 -
1540         if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) {
1541                 struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
1542
1543 @@ -167,6 +164,13 @@ int ip6_output(struct sk_buff *skb)
1544                 return 0;
1545         }
1546
1547 +       /*
1548 +        * IMQ-patch: moved setting skb->dev and skb->protocol from
1549 +        * ip6_finish_output2 to fix crashing at netif_skb_features().
1550 +        */
1551 +       skb->protocol = htons(ETH_P_IPV6);
1552 +       skb->dev = dev;
1553 +
1554         return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING, skb, NULL, dev,
1555                             ip6_finish_output,
1556                             !(IP6CB(skb)->flags & IP6SKB_REROUTED));
1557 diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig
1558 index 56d22ca..58f40f8 100644
1559 --- a/net/netfilter/Kconfig
1560 +++ b/net/netfilter/Kconfig
1561 @@ -641,6 +641,18 @@ config NETFILTER_XT_TARGET_LOG
1562
1563           To compile it as a module, choose M here.  If unsure, say N.
1564
1565 +config NETFILTER_XT_TARGET_IMQ
1566 +        tristate '"IMQ" target support'
1567 +       depends on NETFILTER_XTABLES
1568 +       depends on IP_NF_MANGLE || IP6_NF_MANGLE
1569 +       select IMQ
1570 +       default m if NETFILTER_ADVANCED=n
1571 +        help
1572 +          This option adds a `IMQ' target which is used to specify if and
1573 +          to which imq device packets should get enqueued/dequeued.
1574 +
1575 +          To compile it as a module, choose M here.  If unsure, say N.
1576 +
1577  config NETFILTER_XT_TARGET_MARK
1578         tristate '"MARK" target support'
1579         depends on NETFILTER_ADVANCED
1580 diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile
1581 index a1abf87..2c0cbf4 100644
1582 --- a/net/netfilter/Makefile
1583 +++ b/net/netfilter/Makefile
1584 @@ -82,6 +82,7 @@ obj-$(CONFIG_NETFILTER_XT_TARGET_CT) += xt_CT.o
1585  obj-$(CONFIG_NETFILTER_XT_TARGET_DSCP) += xt_DSCP.o
1586  obj-$(CONFIG_NETFILTER_XT_TARGET_HL) += xt_HL.o
1587  obj-$(CONFIG_NETFILTER_XT_TARGET_HMARK) += xt_HMARK.o
1588 +obj-$(CONFIG_NETFILTER_XT_TARGET_IMQ) += xt_IMQ.o
1589  obj-$(CONFIG_NETFILTER_XT_TARGET_LED) += xt_LED.o
1590  obj-$(CONFIG_NETFILTER_XT_TARGET_LOG) += xt_LOG.o
1591  obj-$(CONFIG_NETFILTER_XT_TARGET_NETMAP) += xt_NETMAP.o
1592 diff --git a/net/netfilter/core.c b/net/netfilter/core.c
1593 index 857ca9f..93fe11b 100644
1594 --- a/net/netfilter/core.c
1595 +++ b/net/netfilter/core.c
1596 @@ -191,9 +191,11 @@ next_hook:
1597                 ret = NF_DROP_GETERR(verdict);
1598                 if (ret == 0)
1599                         ret = -EPERM;
1600 -       } else if ((verdict & NF_VERDICT_MASK) == NF_QUEUE) {
1601 +       } else if ((verdict & NF_VERDICT_MASK) == NF_QUEUE ||
1602 +                  (verdict & NF_VERDICT_MASK) == NF_IMQ_QUEUE) {
1603                 int err = nf_queue(skb, elem, pf, hook, indev, outdev, okfn,
1604 -                                               verdict >> NF_VERDICT_QBITS);
1605 +                                               verdict >> NF_VERDICT_QBITS,
1606 +                                               verdict & NF_VERDICT_MASK);
1607                 if (err < 0) {
1608                         if (err == -ECANCELED)
1609                                 goto next_hook;
1610 diff --git a/net/netfilter/nf_internals.h b/net/netfilter/nf_internals.h
1611 index 3deec99..c1a1397 100644
1612 --- a/net/netfilter/nf_internals.h
1613 +++ b/net/netfilter/nf_internals.h
1614 @@ -29,7 +29,7 @@ extern int nf_queue(struct sk_buff *skb,
1615                     struct net_device *indev,
1616                     struct net_device *outdev,
1617                     int (*okfn)(struct sk_buff *),
1618 -                   unsigned int queuenum);
1619 +                   unsigned int queuenum, unsigned int queuetype);
1620  extern int __init netfilter_queue_init(void);
1621
1622  /* nf_log.c */
1623 diff --git a/net/netfilter/nf_queue.c b/net/netfilter/nf_queue.c
1624 index 5d24b1f..28317dc 100644
1625 --- a/net/netfilter/nf_queue.c
1626 +++ b/net/netfilter/nf_queue.c
1627 @@ -27,6 +27,23 @@
1628   */
1629  static const struct nf_queue_handler __rcu *queue_handler __read_mostly;
1630
1631 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1632 +static const struct nf_queue_handler __rcu *queue_imq_handler __read_mostly;
1633 +
1634 +void nf_register_queue_imq_handler(const struct nf_queue_handler *qh)
1635 +{
1636 +       rcu_assign_pointer(queue_imq_handler, qh);
1637 +}
1638 +EXPORT_SYMBOL_GPL(nf_register_queue_imq_handler);
1639 +
1640 +void nf_unregister_queue_imq_handler(void)
1641 +{
1642 +       RCU_INIT_POINTER(queue_imq_handler, NULL);
1643 +       synchronize_rcu();
1644 +}
1645 +EXPORT_SYMBOL_GPL(nf_unregister_queue_imq_handler);
1646 +#endif
1647 +
1648  /* return EBUSY when somebody else is registered, return EEXIST if the
1649   * same handler is registered, return 0 in case of success. */
1650  void nf_register_queue_handler(const struct nf_queue_handler *qh)
1651 @@ -105,7 +122,8 @@ int nf_queue(struct sk_buff *skb,
1652                       struct net_device *indev,
1653                       struct net_device *outdev,
1654                       int (*okfn)(struct sk_buff *),
1655 -                     unsigned int queuenum)
1656 +                     unsigned int queuenum,
1657 +                     unsigned int queuetype)
1658  {
1659         int status = -ENOENT;
1660         struct nf_queue_entry *entry = NULL;
1661 @@ -115,7 +133,17 @@ int nf_queue(struct sk_buff *skb,
1662         /* QUEUE == DROP if no one is waiting, to be safe. */
1663         rcu_read_lock();
1664
1665 -       qh = rcu_dereference(queue_handler);
1666 +       if (queuetype == NF_IMQ_QUEUE) {
1667 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1668 +               qh = rcu_dereference(queue_imq_handler);
1669 +#else
1670 +               BUG();
1671 +               goto err_unlock;
1672 +#endif
1673 +       } else {
1674 +               qh = rcu_dereference(queue_handler);
1675 +       }
1676 +
1677         if (!qh) {
1678                 status = -ESRCH;
1679                 goto err_unlock;
1680 @@ -205,9 +233,11 @@ void nf_reinject(struct nf_queue_entry *entry, unsigned int verdict)
1681                 local_bh_enable();
1682                 break;
1683         case NF_QUEUE:
1684 +       case NF_IMQ_QUEUE:
1685                 err = nf_queue(skb, elem, entry->pf, entry->hook,
1686                                 entry->indev, entry->outdev, entry->okfn,
1687 -                               verdict >> NF_VERDICT_QBITS);
1688 +                               verdict >> NF_VERDICT_QBITS,
1689 +                               verdict & NF_VERDICT_MASK);
1690                 if (err < 0) {
1691                         if (err == -ECANCELED)
1692                                 goto next_hook;
1693 diff --git a/net/netfilter/xt_IMQ.c b/net/netfilter/xt_IMQ.c
1694 new file mode 100644
1695 index 0000000..1c3cd66
1696 --- /dev/null
1697 +++ b/net/netfilter/xt_IMQ.c
1698 @@ -0,0 +1,72 @@
1699 +/*
1700 + * This target marks packets to be enqueued to an imq device
1701 + */
1702 +#include <linux/module.h>
1703 +#include <linux/skbuff.h>
1704 +#include <linux/netfilter/x_tables.h>
1705 +#include <linux/netfilter/xt_IMQ.h>
1706 +#include <linux/imq.h>
1707 +
1708 +static unsigned int imq_target(struct sk_buff *pskb,
1709 +                               const struct xt_action_param *par)
1710 +{
1711 +       const struct xt_imq_info *mr = par->targinfo;
1712 +
1713 +       pskb->imq_flags = (mr->todev & IMQ_F_IFMASK) | IMQ_F_ENQUEUE;
1714 +
1715 +       return XT_CONTINUE;
1716 +}
1717 +
1718 +static int imq_checkentry(const struct xt_tgchk_param *par)
1719 +{
1720 +       struct xt_imq_info *mr = par->targinfo;
1721 +
1722 +       if (mr->todev > IMQ_MAX_DEVS - 1) {
1723 +               pr_warn("IMQ: invalid device specified, highest is %u\n",
1724 +                       IMQ_MAX_DEVS - 1);
1725 +               return -EINVAL;
1726 +       }
1727 +
1728 +       return 0;
1729 +}
1730 +
1731 +static struct xt_target xt_imq_reg[] __read_mostly = {
1732 +       {
1733 +               .name           = "IMQ",
1734 +               .family         = AF_INET,
1735 +               .checkentry     = imq_checkentry,
1736 +               .target         = imq_target,
1737 +               .targetsize     = sizeof(struct xt_imq_info),
1738 +               .table          = "mangle",
1739 +               .me             = THIS_MODULE
1740 +       },
1741 +       {
1742 +               .name           = "IMQ",
1743 +               .family         = AF_INET6,
1744 +               .checkentry     = imq_checkentry,
1745 +               .target         = imq_target,
1746 +               .targetsize     = sizeof(struct xt_imq_info),
1747 +               .table          = "mangle",
1748 +               .me             = THIS_MODULE
1749 +       },
1750 +};
1751 +
1752 +static int __init imq_init(void)
1753 +{
1754 +       return xt_register_targets(xt_imq_reg, ARRAY_SIZE(xt_imq_reg));
1755 +}
1756 +
1757 +static void __exit imq_fini(void)
1758 +{
1759 +       xt_unregister_targets(xt_imq_reg, ARRAY_SIZE(xt_imq_reg));
1760 +}
1761 +
1762 +module_init(imq_init);
1763 +module_exit(imq_fini);
1764 +
1765 +MODULE_AUTHOR("http://www.linuximq.net");
1766 +MODULE_DESCRIPTION("Pseudo-driver for the intermediate queue device. See http://www.linuximq.net/ for more information.");
1767 +MODULE_LICENSE("GPL");
1768 +MODULE_ALIAS("ipt_IMQ");
1769 +MODULE_ALIAS("ip6t_IMQ");
1770 +