kernel-imq.patch

   1 diff -urNp -x '*.orig' linux-4.4/drivers/net/Kconfig linux-4.4/drivers/net/Kconfig
   2 --- linux-4.4/drivers/net/Kconfig       2021-02-24 16:53:23.647128839 +0100
   3 +++ linux-4.4/drivers/net/Kconfig       2021-02-24 16:53:35.787510557 +0100
   4 @@ -234,6 +234,125 @@ config RIONET_RX_SIZE
   5         depends on RIONET
   6         default "128"
   7
   8 +config IMQ
   9 +       tristate "IMQ (intermediate queueing device) support"
  10 +       depends on NETDEVICES && NETFILTER
  11 +       ---help---
  12 +         The IMQ device(s) is used as placeholder for QoS queueing
  13 +         disciplines. Every packet entering/leaving the IP stack can be
  14 +         directed through the IMQ device where it's enqueued/dequeued to the
  15 +         attached qdisc. This allows you to treat network devices as classes
  16 +         and distribute bandwidth among them. Iptables is used to specify
  17 +         through which IMQ device, if any, packets travel.
  18 +
  19 +         More information at: https://github.com/imq/linuximq
  20 +
  21 +         To compile this driver as a module, choose M here: the module
  22 +         will be called imq.  If unsure, say N.
  23 +
  24 +choice
  25 +       prompt "IMQ behavior (PRE/POSTROUTING)"
  26 +       depends on IMQ
  27 +       default IMQ_BEHAVIOR_AB
  28 +       help
  29 +         This setting defines how IMQ behaves in respect to its
  30 +         hooking in PREROUTING and POSTROUTING.
  31 +
  32 +         IMQ can work in any of the following ways:
  33 +
  34 +             PREROUTING   |      POSTROUTING
  35 +         -----------------|-------------------
  36 +         #1  After NAT    |      After NAT
  37 +         #2  After NAT    |      Before NAT
  38 +         #3  Before NAT   |      After NAT
  39 +         #4  Before NAT   |      Before NAT
  40 +
  41 +         The default behavior is to hook before NAT on PREROUTING
  42 +         and after NAT on POSTROUTING (#3).
  43 +
  44 +         This settings are specially usefull when trying to use IMQ
  45 +         to shape NATed clients.
  46 +
  47 +         More information can be found at: https://github.com/imq/linuximq
  48 +
  49 +         If not sure leave the default settings alone.
  50 +
  51 +config IMQ_BEHAVIOR_AA
  52 +       bool "IMQ AA"
  53 +       help
  54 +         This setting defines how IMQ behaves in respect to its
  55 +         hooking in PREROUTING and POSTROUTING.
  56 +
  57 +         Choosing this option will make IMQ hook like this:
  58 +
  59 +         PREROUTING:   After NAT
  60 +         POSTROUTING:  After NAT
  61 +
  62 +         More information can be found at: https://github.com/imq/linuximq
  63 +
  64 +         If not sure leave the default settings alone.
  65 +
  66 +config IMQ_BEHAVIOR_AB
  67 +       bool "IMQ AB"
  68 +       help
  69 +         This setting defines how IMQ behaves in respect to its
  70 +         hooking in PREROUTING and POSTROUTING.
  71 +
  72 +         Choosing this option will make IMQ hook like this:
  73 +
  74 +         PREROUTING:   After NAT
  75 +         POSTROUTING:  Before NAT
  76 +
  77 +         More information can be found at: https://github.com/imq/linuximq
  78 +
  79 +         If not sure leave the default settings alone.
  80 +
  81 +config IMQ_BEHAVIOR_BA
  82 +       bool "IMQ BA"
  83 +       help
  84 +         This setting defines how IMQ behaves in respect to its
  85 +         hooking in PREROUTING and POSTROUTING.
  86 +
  87 +         Choosing this option will make IMQ hook like this:
  88 +
  89 +         PREROUTING:   Before NAT
  90 +         POSTROUTING:  After NAT
  91 +
  92 +         More information can be found at: https://github.com/imq/linuximq
  93 +
  94 +         If not sure leave the default settings alone.
  95 +
  96 +config IMQ_BEHAVIOR_BB
  97 +       bool "IMQ BB"
  98 +       help
  99 +         This setting defines how IMQ behaves in respect to its
 100 +         hooking in PREROUTING and POSTROUTING.
 101 +
 102 +         Choosing this option will make IMQ hook like this:
 103 +
 104 +         PREROUTING:   Before NAT
 105 +         POSTROUTING:  Before NAT
 106 +
 107 +         More information can be found at: https://github.com/imq/linuximq
 108 +
 109 +         If not sure leave the default settings alone.
 110 +
 111 +endchoice
 112 +
 113 +config IMQ_NUM_DEVS
 114 +       int "Number of IMQ devices"
 115 +       range 2 16
 116 +       depends on IMQ
 117 +       default "16"
 118 +       help
 119 +         This setting defines how many IMQ devices will be created.
 120 +
 121 +         The default value is 16.
 122 +
 123 +         More information can be found at: https://github.com/imq/linuximq
 124 +
 125 +         If not sure leave the default settings alone.
 126 +
 127  config TUN
 128         tristate "Universal TUN/TAP device driver support"
 129         depends on INET
 130 diff -urNp -x '*.orig' linux-4.4/drivers/net/Makefile linux-4.4/drivers/net/Makefile
 131 --- linux-4.4/drivers/net/Makefile      2016-01-11 00:01:32.000000000 +0100
 132 +++ linux-4.4/drivers/net/Makefile      2021-02-24 16:53:35.787510557 +0100
 133 @@ -10,6 +10,7 @@ obj-$(CONFIG_IPVLAN) += ipvlan/
 134  obj-$(CONFIG_DUMMY) += dummy.o
 135  obj-$(CONFIG_EQUALIZER) += eql.o
 136  obj-$(CONFIG_IFB) += ifb.o
 137 +obj-$(CONFIG_IMQ) += imq.o
 138  obj-$(CONFIG_MACVLAN) += macvlan.o
 139  obj-$(CONFIG_MACVTAP) += macvtap.o
 140  obj-$(CONFIG_MII) += mii.o
 141 diff -urNp -x '*.orig' linux-4.4/drivers/net/imq.c linux-4.4/drivers/net/imq.c
 142 --- linux-4.4/drivers/net/imq.c 1970-01-01 01:00:00.000000000 +0100
 143 +++ linux-4.4/drivers/net/imq.c 2021-02-24 16:53:35.787510557 +0100
 144 @@ -0,0 +1,903 @@
 145 +/*
 146 + *             Pseudo-driver for the intermediate queue device.
 147 + *
 148 + *             This program is free software; you can redistribute it and/or
 149 + *             modify it under the terms of the GNU General Public License
 150 + *             as published by the Free Software Foundation; either version
 151 + *             2 of the License, or (at your option) any later version.
 152 + *
 153 + * Authors:    Patrick McHardy, <kaber@trash.net>
 154 + *
 155 + *            The first version was written by Martin Devera, <devik@cdi.cz>
 156 + *
 157 + *                        See Creditis.txt
 158 + */
 159 +
 160 +#include <linux/module.h>
 161 +#include <linux/kernel.h>
 162 +#include <linux/moduleparam.h>
 163 +#include <linux/list.h>
 164 +#include <linux/skbuff.h>
 165 +#include <linux/netdevice.h>
 166 +#include <linux/etherdevice.h>
 167 +#include <linux/rtnetlink.h>
 168 +#include <linux/if_arp.h>
 169 +#include <linux/netfilter.h>
 170 +#include <linux/netfilter_ipv4.h>
 171 +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 172 +       #include <linux/netfilter_ipv6.h>
 173 +#endif
 174 +#include <linux/imq.h>
 175 +#include <net/pkt_sched.h>
 176 +#include <net/netfilter/nf_queue.h>
 177 +#include <net/sock.h>
 178 +#include <linux/ip.h>
 179 +#include <linux/ipv6.h>
 180 +#include <linux/if_vlan.h>
 181 +#include <linux/if_pppox.h>
 182 +#include <net/ip.h>
 183 +#include <net/ipv6.h>
 184 +
 185 +static int imq_nf_queue(struct nf_queue_entry *entry, unsigned queue_num);
 186 +
 187 +static nf_hookfn imq_nf_hook;
 188 +
 189 +static struct nf_hook_ops imq_ops[] = {
 190 +       {
 191 +       /* imq_ingress_ipv4 */
 192 +               .hook           = imq_nf_hook,
 193 +               .pf             = PF_INET,
 194 +               .hooknum        = NF_INET_PRE_ROUTING,
 195 +#if defined(CONFIG_IMQ_BEHAVIOR_BA) || defined(CONFIG_IMQ_BEHAVIOR_BB)
 196 +               .priority       = NF_IP_PRI_MANGLE + 1,
 197 +#else
 198 +               .priority       = NF_IP_PRI_NAT_DST + 1,
 199 +#endif
 200 +       },
 201 +       {
 202 +       /* imq_egress_ipv4 */
 203 +               .hook           = imq_nf_hook,
 204 +               .pf             = PF_INET,
 205 +               .hooknum        = NF_INET_POST_ROUTING,
 206 +#if defined(CONFIG_IMQ_BEHAVIOR_AA) || defined(CONFIG_IMQ_BEHAVIOR_BA)
 207 +               .priority       = NF_IP_PRI_LAST,
 208 +#else
 209 +               .priority       = NF_IP_PRI_NAT_SRC - 1,
 210 +#endif
 211 +       },
 212 +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 213 +       {
 214 +       /* imq_ingress_ipv6 */
 215 +               .hook           = imq_nf_hook,
 216 +               .pf             = PF_INET6,
 217 +               .hooknum        = NF_INET_PRE_ROUTING,
 218 +#if defined(CONFIG_IMQ_BEHAVIOR_BA) || defined(CONFIG_IMQ_BEHAVIOR_BB)
 219 +               .priority       = NF_IP6_PRI_MANGLE + 1,
 220 +#else
 221 +               .priority       = NF_IP6_PRI_NAT_DST + 1,
 222 +#endif
 223 +       },
 224 +       {
 225 +       /* imq_egress_ipv6 */
 226 +               .hook           = imq_nf_hook,
 227 +               .pf             = PF_INET6,
 228 +               .hooknum        = NF_INET_POST_ROUTING,
 229 +#if defined(CONFIG_IMQ_BEHAVIOR_AA) || defined(CONFIG_IMQ_BEHAVIOR_BA)
 230 +               .priority       = NF_IP6_PRI_LAST,
 231 +#else
 232 +               .priority       = NF_IP6_PRI_NAT_SRC - 1,
 233 +#endif
 234 +       },
 235 +#endif
 236 +};
 237 +
 238 +#if defined(CONFIG_IMQ_NUM_DEVS)
 239 +static int numdevs = CONFIG_IMQ_NUM_DEVS;
 240 +#else
 241 +static int numdevs = IMQ_MAX_DEVS;
 242 +#endif
 243 +
 244 +static struct net_device *imq_devs_cache[IMQ_MAX_DEVS];
 245 +
 246 +#define IMQ_MAX_QUEUES 32
 247 +static int numqueues = 1;
 248 +static u32 imq_hashrnd;
 249 +static int imq_dev_accurate_stats = 1;
 250 +
 251 +static inline __be16 pppoe_proto(const struct sk_buff *skb)
 252 +{
 253 +       return *((__be16 *)(skb_mac_header(skb) + ETH_HLEN +
 254 +                       sizeof(struct pppoe_hdr)));
 255 +}
 256 +
 257 +static u16 imq_hash(struct net_device *dev, struct sk_buff *skb)
 258 +{
 259 +       unsigned int pull_len;
 260 +       u16 protocol = skb->protocol;
 261 +       u32 addr1, addr2;
 262 +       u32 hash, ihl = 0;
 263 +       union {
 264 +               u16 in16[2];
 265 +               u32 in32;
 266 +       } ports;
 267 +       u8 ip_proto;
 268 +
 269 +       pull_len = 0;
 270 +
 271 +recheck:
 272 +       switch (protocol) {
 273 +       case htons(ETH_P_8021Q): {
 274 +               if (unlikely(skb_pull(skb, VLAN_HLEN) == NULL))
 275 +                       goto other;
 276 +
 277 +               pull_len += VLAN_HLEN;
 278 +               skb->network_header += VLAN_HLEN;
 279 +
 280 +               protocol = vlan_eth_hdr(skb)->h_vlan_encapsulated_proto;
 281 +               goto recheck;
 282 +       }
 283 +
 284 +       case htons(ETH_P_PPP_SES): {
 285 +               if (unlikely(skb_pull(skb, PPPOE_SES_HLEN) == NULL))
 286 +                       goto other;
 287 +
 288 +               pull_len += PPPOE_SES_HLEN;
 289 +               skb->network_header += PPPOE_SES_HLEN;
 290 +
 291 +               protocol = pppoe_proto(skb);
 292 +               goto recheck;
 293 +       }
 294 +
 295 +       case htons(ETH_P_IP): {
 296 +               const struct iphdr *iph = ip_hdr(skb);
 297 +
 298 +               if (unlikely(!pskb_may_pull(skb, sizeof(struct iphdr))))
 299 +                       goto other;
 300 +
 301 +               addr1 = iph->daddr;
 302 +               addr2 = iph->saddr;
 303 +
 304 +               ip_proto = !(ip_hdr(skb)->frag_off & htons(IP_MF | IP_OFFSET)) ?
 305 +                                iph->protocol : 0;
 306 +               ihl = ip_hdrlen(skb);
 307 +
 308 +               break;
 309 +       }
 310 +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 311 +       case htons(ETH_P_IPV6): {
 312 +               const struct ipv6hdr *iph = ipv6_hdr(skb);
 313 +               __be16 fo = 0;
 314 +
 315 +               if (unlikely(!pskb_may_pull(skb, sizeof(struct ipv6hdr))))
 316 +                       goto other;
 317 +
 318 +               addr1 = iph->daddr.s6_addr32[3];
 319 +               addr2 = iph->saddr.s6_addr32[3];
 320 +               ihl = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &ip_proto,
 321 +                                      &fo);
 322 +               if (unlikely(ihl < 0))
 323 +                       goto other;
 324 +
 325 +               break;
 326 +       }
 327 +#endif
 328 +       default:
 329 +other:
 330 +               if (pull_len != 0) {
 331 +                       skb_push(skb, pull_len);
 332 +                       skb->network_header -= pull_len;
 333 +               }
 334 +
 335 +               return (u16)(ntohs(protocol) % dev->real_num_tx_queues);
 336 +       }
 337 +
 338 +       if (addr1 > addr2)
 339 +               swap(addr1, addr2);
 340 +
 341 +       switch (ip_proto) {
 342 +       case IPPROTO_TCP:
 343 +       case IPPROTO_UDP:
 344 +       case IPPROTO_DCCP:
 345 +       case IPPROTO_ESP:
 346 +       case IPPROTO_AH:
 347 +       case IPPROTO_SCTP:
 348 +       case IPPROTO_UDPLITE: {
 349 +               if (likely(skb_copy_bits(skb, ihl, &ports.in32, 4) >= 0)) {
 350 +                       if (ports.in16[0] > ports.in16[1])
 351 +                               swap(ports.in16[0], ports.in16[1]);
 352 +                       break;
 353 +               }
 354 +               /* fall-through */
 355 +       }
 356 +       default:
 357 +               ports.in32 = 0;
 358 +               break;
 359 +       }
 360 +
 361 +       if (pull_len != 0) {
 362 +               skb_push(skb, pull_len);
 363 +               skb->network_header -= pull_len;
 364 +       }
 365 +
 366 +       hash = jhash_3words(addr1, addr2, ports.in32, imq_hashrnd ^ ip_proto);
 367 +
 368 +       return (u16)(((u64)hash * dev->real_num_tx_queues) >> 32);
 369 +}
 370 +
 371 +static inline bool sk_tx_queue_recorded(struct sock *sk)
 372 +{
 373 +       return (sk_tx_queue_get(sk) >= 0);
 374 +}
 375 +
 376 +static struct netdev_queue *imq_select_queue(struct net_device *dev,
 377 +                                               struct sk_buff *skb)
 378 +{
 379 +       u16 queue_index = 0;
 380 +       u32 hash;
 381 +
 382 +       if (likely(dev->real_num_tx_queues == 1))
 383 +               goto out;
 384 +
 385 +       /* IMQ can be receiving ingress or engress packets. */
 386 +
 387 +       /* Check first for if rx_queue is set */
 388 +       if (skb_rx_queue_recorded(skb)) {
 389 +               queue_index = skb_get_rx_queue(skb);
 390 +               goto out;
 391 +       }
 392 +
 393 +       /* Check if socket has tx_queue set */
 394 +       if (sk_tx_queue_recorded(skb->sk)) {
 395 +               queue_index = sk_tx_queue_get(skb->sk);
 396 +               goto out;
 397 +       }
 398 +
 399 +       /* Try use socket hash */
 400 +       if (skb->sk && skb->sk->sk_hash) {
 401 +               hash = skb->sk->sk_hash;
 402 +               queue_index =
 403 +                       (u16)(((u64)hash * dev->real_num_tx_queues) >> 32);
 404 +               goto out;
 405 +       }
 406 +
 407 +       /* Generate hash from packet data */
 408 +       queue_index = imq_hash(dev, skb);
 409 +
 410 +out:
 411 +       if (unlikely(queue_index >= dev->real_num_tx_queues))
 412 +               queue_index = (u16)((u32)queue_index % dev->real_num_tx_queues);
 413 +
 414 +       skb_set_queue_mapping(skb, queue_index);
 415 +       return netdev_get_tx_queue(dev, queue_index);
 416 +}
 417 +
 418 +static struct net_device_stats *imq_get_stats(struct net_device *dev)
 419 +{
 420 +       return &dev->stats;
 421 +}
 422 +
 423 +/* called for packets kfree'd in qdiscs at places other than enqueue */
 424 +static void imq_skb_destructor(struct sk_buff *skb)
 425 +{
 426 +       struct nf_queue_entry *entry = skb->nf_queue_entry;
 427 +
 428 +       skb->nf_queue_entry = NULL;
 429 +
 430 +       if (entry) {
 431 +               nf_queue_entry_release_refs(entry);
 432 +               kfree(entry);
 433 +       }
 434 +
 435 +       skb_restore_cb(skb); /* kfree backup */
 436 +}
 437 +
 438 +static void imq_done_check_queue_mapping(struct sk_buff *skb,
 439 +                                        struct net_device *dev)
 440 +{
 441 +       unsigned int queue_index;
 442 +
 443 +       /* Don't let queue_mapping be left too large after exiting IMQ */
 444 +       if (likely(skb->dev != dev && skb->dev != NULL)) {
 445 +               queue_index = skb_get_queue_mapping(skb);
 446 +               if (unlikely(queue_index >= skb->dev->real_num_tx_queues)) {
 447 +                       queue_index = (u16)((u32)queue_index %
 448 +                                               skb->dev->real_num_tx_queues);
 449 +                       skb_set_queue_mapping(skb, queue_index);
 450 +               }
 451 +       } else {
 452 +               /* skb->dev was IMQ device itself or NULL, be on safe side and
 453 +                * just clear queue mapping.
 454 +                */
 455 +               skb_set_queue_mapping(skb, 0);
 456 +       }
 457 +}
 458 +
 459 +static netdev_tx_t imq_dev_xmit(struct sk_buff *skb, struct net_device *dev)
 460 +{
 461 +       struct nf_queue_entry *entry = skb->nf_queue_entry;
 462 +
 463 +       skb->nf_queue_entry = NULL;
 464 +       dev->trans_start = jiffies;
 465 +
 466 +       dev->stats.tx_bytes += skb->len;
 467 +       dev->stats.tx_packets++;
 468 +
 469 +       if (unlikely(entry == NULL)) {
 470 +               /* We don't know what is going on here.. packet is queued for
 471 +                * imq device, but (probably) not by us.
 472 +                *
 473 +                * If this packet was not send here by imq_nf_queue(), then
 474 +                * skb_save_cb() was not used and skb_free() should not show:
 475 +                *   WARNING: IMQ: kfree_skb: skb->cb_next:..
 476 +                * and/or
 477 +                *   WARNING: IMQ: kfree_skb: skb->nf_queue_entry...
 478 +                *
 479 +                * However if this message is shown, then IMQ is somehow broken
 480 +                * and you should report this to linuximq.net.
 481 +                */
 482 +
 483 +               /* imq_dev_xmit is black hole that eats all packets, report that
 484 +                * we eat this packet happily and increase dropped counters.
 485 +                */
 486 +
 487 +               dev->stats.tx_dropped++;
 488 +               dev_kfree_skb(skb);
 489 +
 490 +               return NETDEV_TX_OK;
 491 +       }
 492 +
 493 +       skb_restore_cb(skb); /* restore skb->cb */
 494 +
 495 +       skb->imq_flags = 0;
 496 +       skb->destructor = NULL;
 497 +
 498 +       imq_done_check_queue_mapping(skb, dev);
 499 +
 500 +       nf_reinject(entry, NF_ACCEPT);
 501 +
 502 +       return NETDEV_TX_OK;
 503 +}
 504 +
 505 +static struct net_device *get_imq_device_by_index(int index)
 506 +{
 507 +       struct net_device *dev = NULL;
 508 +       struct net *net;
 509 +       char buf[8];
 510 +
 511 +       /* get device by name and cache result */
 512 +       snprintf(buf, sizeof(buf), "imq%d", index);
 513 +
 514 +       /* Search device from all namespaces. */
 515 +       for_each_net(net) {
 516 +               dev = dev_get_by_name(net, buf);
 517 +               if (dev)
 518 +                       break;
 519 +       }
 520 +
 521 +       if (WARN_ON_ONCE(dev == NULL)) {
 522 +               /* IMQ device not found. Exotic config? */
 523 +               return ERR_PTR(-ENODEV);
 524 +       }
 525 +
 526 +       imq_devs_cache[index] = dev;
 527 +       dev_put(dev);
 528 +
 529 +       return dev;
 530 +}
 531 +
 532 +static struct nf_queue_entry *nf_queue_entry_dup(struct nf_queue_entry *e)
 533 +{
 534 +       struct nf_queue_entry *entry = kmemdup(e, e->size, GFP_ATOMIC);
 535 +       if (entry) {
 536 +               nf_queue_entry_get_refs(entry);
 537 +                       return entry;
 538 +       }
 539 +       return NULL;
 540 +}
 541 +
 542 +#ifdef CONFIG_BRIDGE_NETFILTER
 543 +/* When called from bridge netfilter, skb->data must point to MAC header
 544 + * before calling skb_gso_segment(). Else, original MAC header is lost
 545 + * and segmented skbs will be sent to wrong destination.
 546 + */
 547 +static void nf_bridge_adjust_skb_data(struct sk_buff *skb)
 548 +{
 549 +       if (skb->nf_bridge)
 550 +               __skb_push(skb, skb->network_header - skb->mac_header);
 551 +}
 552 +
 553 +static void nf_bridge_adjust_segmented_data(struct sk_buff *skb)
 554 +{
 555 +       if (skb->nf_bridge)
 556 +               __skb_pull(skb, skb->network_header - skb->mac_header);
 557 +}
 558 +#else
 559 +#define nf_bridge_adjust_skb_data(s) do {} while (0)
 560 +#define nf_bridge_adjust_segmented_data(s) do {} while (0)
 561 +#endif
 562 +
 563 +static void free_entry(struct nf_queue_entry *entry)
 564 +{
 565 +       nf_queue_entry_release_refs(entry);
 566 +       kfree(entry);
 567 +}
 568 +
 569 +static int __imq_nf_queue(struct nf_queue_entry *entry, struct net_device *dev);
 570 +
 571 +static int __imq_nf_queue_gso(struct nf_queue_entry *entry,
 572 +                             struct net_device *dev, struct sk_buff *skb)
 573 +{
 574 +       int ret = -ENOMEM;
 575 +       struct nf_queue_entry *entry_seg;
 576 +
 577 +       nf_bridge_adjust_segmented_data(skb);
 578 +
 579 +       if (skb->next == NULL) { /* last packet, no need to copy entry */
 580 +               struct sk_buff *gso_skb = entry->skb;
 581 +               entry->skb = skb;
 582 +               ret = __imq_nf_queue(entry, dev);
 583 +               if (ret)
 584 +                       entry->skb = gso_skb;
 585 +               return ret;
 586 +       }
 587 +
 588 +       skb->next = NULL;
 589 +
 590 +       entry_seg = nf_queue_entry_dup(entry);
 591 +       if (entry_seg) {
 592 +               entry_seg->skb = skb;
 593 +               ret = __imq_nf_queue(entry_seg, dev);
 594 +               if (ret)
 595 +                       free_entry(entry_seg);
 596 +       }
 597 +       return ret;
 598 +}
 599 +
 600 +static int imq_nf_queue(struct nf_queue_entry *entry, unsigned queue_num)
 601 +{
 602 +       struct sk_buff *skb, *segs;
 603 +       struct net_device *dev;
 604 +       unsigned int queued;
 605 +       int index, retval, err;
 606 +
 607 +       index = entry->skb->imq_flags & IMQ_F_IFMASK;
 608 +       if (unlikely(index > numdevs - 1)) {
 609 +               if (net_ratelimit())
 610 +                       pr_warn("IMQ: invalid device specified, highest is %u\n",
 611 +                               numdevs - 1);
 612 +               retval = -EINVAL;
 613 +               goto out_no_dev;
 614 +       }
 615 +
 616 +       /* check for imq device by index from cache */
 617 +       dev = imq_devs_cache[index];
 618 +       if (unlikely(!dev)) {
 619 +               dev = get_imq_device_by_index(index);
 620 +               if (IS_ERR(dev)) {
 621 +                       retval = PTR_ERR(dev);
 622 +                       goto out_no_dev;
 623 +               }
 624 +       }
 625 +
 626 +       if (unlikely(!(dev->flags & IFF_UP))) {
 627 +               entry->skb->imq_flags = 0;
 628 +               retval = -ECANCELED;
 629 +               goto out_no_dev;
 630 +       }
 631 +
 632 +       /* Since 3.10.x, GSO handling moved here as result of upstream commit
 633 +        * a5fedd43d5f6c94c71053a66e4c3d2e35f1731a2 (netfilter: move
 634 +        * skb_gso_segment into nfnetlink_queue module).
 635 +        *
 636 +        * Following code replicates the gso handling from
 637 +        * 'net/netfilter/nfnetlink_queue_core.c':nfqnl_enqueue_packet().
 638 +        */
 639 +
 640 +       skb = entry->skb;
 641 +
 642 +       switch (entry->state.pf) {
 643 +       case NFPROTO_IPV4:
 644 +               skb->protocol = htons(ETH_P_IP);
 645 +               break;
 646 +       case NFPROTO_IPV6:
 647 +               skb->protocol = htons(ETH_P_IPV6);
 648 +               break;
 649 +       }
 650 +
 651 +       if (!skb_is_gso(entry->skb))
 652 +               return __imq_nf_queue(entry, dev);
 653 +
 654 +       nf_bridge_adjust_skb_data(skb);
 655 +       segs = skb_gso_segment(skb, 0);
 656 +       /* Does not use PTR_ERR to limit the number of error codes that can be
 657 +        * returned by nf_queue.  For instance, callers rely on -ECANCELED to
 658 +        * mean 'ignore this hook'.
 659 +        */
 660 +       err = -ENOBUFS;
 661 +       if (IS_ERR(segs))
 662 +               goto out_err;
 663 +       queued = 0;
 664 +       err = 0;
 665 +       do {
 666 +               struct sk_buff *nskb = segs->next;
 667 +               if (nskb && nskb->next)
 668 +                       nskb->cb_next = NULL;
 669 +               if (err == 0)
 670 +                       err = __imq_nf_queue_gso(entry, dev, segs);
 671 +               if (err == 0)
 672 +                       queued++;
 673 +               else
 674 +                       kfree_skb(segs);
 675 +               segs = nskb;
 676 +       } while (segs);
 677 +
 678 +       if (queued) {
 679 +               if (err) /* some segments are already queued */
 680 +                       free_entry(entry);
 681 +               kfree_skb(skb);
 682 +               return 0;
 683 +       }
 684 +
 685 +out_err:
 686 +       nf_bridge_adjust_segmented_data(skb);
 687 +       retval = err;
 688 +out_no_dev:
 689 +       return retval;
 690 +}
 691 +
 692 +static int __imq_nf_queue(struct nf_queue_entry *entry, struct net_device *dev)
 693 +{
 694 +       struct sk_buff *skb_orig, *skb, *skb_shared, *skb_popd;
 695 +       struct Qdisc *q;
 696 +       struct netdev_queue *txq;
 697 +       spinlock_t *root_lock;
 698 +       int users;
 699 +       int retval = -EINVAL;
 700 +       unsigned int orig_queue_index;
 701 +
 702 +       dev->last_rx = jiffies;
 703 +
 704 +       skb = entry->skb;
 705 +       skb_orig = NULL;
 706 +
 707 +       /* skb has owner? => make clone */
 708 +       if (unlikely(skb->destructor)) {
 709 +               skb_orig = skb;
 710 +               skb = skb_clone(skb, GFP_ATOMIC);
 711 +               if (unlikely(!skb)) {
 712 +                       retval = -ENOMEM;
 713 +                       goto out;
 714 +               }
 715 +               skb->cb_next = NULL;
 716 +               entry->skb = skb;
 717 +       }
 718 +
 719 +       dev->stats.rx_bytes += skb->len;
 720 +       dev->stats.rx_packets++;
 721 +
 722 +       if (!skb->dev) {
 723 +               /* skb->dev == NULL causes problems, try the find cause. */
 724 +               if (net_ratelimit()) {
 725 +                       dev_warn(&dev->dev,
 726 +                                "received packet with skb->dev == NULL\n");
 727 +                       dump_stack();
 728 +               }
 729 +
 730 +               skb->dev = dev;
 731 +       }
 732 +
 733 +       /* Disables softirqs for lock below */
 734 +       rcu_read_lock_bh();
 735 +
 736 +       /* Multi-queue selection */
 737 +       orig_queue_index = skb_get_queue_mapping(skb);
 738 +       txq = imq_select_queue(dev, skb);
 739 +
 740 +       q = rcu_dereference(txq->qdisc);
 741 +       if (unlikely(!q->enqueue))
 742 +               goto packet_not_eaten_by_imq_dev;
 743 +
 744 +       skb->nf_queue_entry = entry;
 745 +       root_lock = qdisc_lock(q);
 746 +       spin_lock(root_lock);
 747 +
 748 +       users = atomic_read(&skb->users);
 749 +
 750 +       skb_shared = skb_get(skb); /* increase reference count by one */
 751 +
 752 +       /* backup skb->cb, as qdisc layer will overwrite it */
 753 +       skb_save_cb(skb_shared);
 754 +       qdisc_enqueue_root(skb_shared, q); /* might kfree_skb */
 755 +       if (likely(atomic_read(&skb_shared->users) == users + 1)) {
 756 +               bool validate;
 757 +
 758 +               kfree_skb(skb_shared); /* decrease reference count by one */
 759 +
 760 +               skb->destructor = &imq_skb_destructor;
 761 +
 762 +               skb_popd = qdisc_dequeue_skb(q, &validate);
 763 +
 764 +               /* cloned? */
 765 +               if (unlikely(skb_orig))
 766 +                       kfree_skb(skb_orig); /* free original */
 767 +
 768 +               spin_unlock(root_lock);
 769 +
 770 +#if 0
 771 +               /* schedule qdisc dequeue */
 772 +               __netif_schedule(q);
 773 +#else
 774 +               if (likely(skb_popd)) {
 775 +                       /* Note that we validate skb (GSO, checksum, ...) outside of locks */
 776 +                       if (validate)
 777 +                       skb_popd = validate_xmit_skb_list(skb_popd, dev);
 778 +
 779 +                       if (skb_popd) {
 780 +                               int dummy_ret;
 781 +                               int cpu = smp_processor_id(); /* ok because BHs are off */
 782 +
 783 +                               txq = skb_get_tx_queue(dev, skb_popd);
 784 +                               /*
 785 +                               IMQ device will not be frozen or stoped, and it always be successful.
 786 +                               So we need not check its status and return value to accelerate.
 787 +                               */
 788 +                               if (imq_dev_accurate_stats && txq->xmit_lock_owner != cpu) {
 789 +                                       HARD_TX_LOCK(dev, txq, cpu);
 790 +                                       if (!netif_xmit_frozen_or_stopped(txq)) {
 791 +                                               dev_hard_start_xmit(skb_popd, dev, txq, &dummy_ret);
 792 +                                       }
 793 +                                       HARD_TX_UNLOCK(dev, txq);
 794 +                               } else {
 795 +                                       if (!netif_xmit_frozen_or_stopped(txq)) {
 796 +                                               dev_hard_start_xmit(skb_popd, dev, txq, &dummy_ret);
 797 +                                       }
 798 +                               }
 799 +                       }
 800 +               } else {
 801 +                       /* No ready skb, then schedule it */
 802 +                       __netif_schedule(q);
 803 +               }
 804 +#endif
 805 +               rcu_read_unlock_bh();
 806 +               retval = 0;
 807 +               goto out;
 808 +       } else {
 809 +               skb_restore_cb(skb_shared); /* restore skb->cb */
 810 +               skb->nf_queue_entry = NULL;
 811 +               /*
 812 +                * qdisc dropped packet and decreased skb reference count of
 813 +                * skb, so we don't really want to and try refree as that would
 814 +                * actually destroy the skb.
 815 +                */
 816 +               spin_unlock(root_lock);
 817 +               goto packet_not_eaten_by_imq_dev;
 818 +       }
 819 +
 820 +packet_not_eaten_by_imq_dev:
 821 +       skb_set_queue_mapping(skb, orig_queue_index);
 822 +       rcu_read_unlock_bh();
 823 +
 824 +       /* cloned? restore original */
 825 +       if (unlikely(skb_orig)) {
 826 +               kfree_skb(skb);
 827 +               entry->skb = skb_orig;
 828 +       }
 829 +       retval = -1;
 830 +out:
 831 +       return retval;
 832 +}
 833 +static unsigned int imq_nf_hook(void *priv,
 834 +                               struct sk_buff *skb,
 835 +                               const struct nf_hook_state *state)
 836 +{
 837 +       return (skb->imq_flags & IMQ_F_ENQUEUE) ? NF_IMQ_QUEUE : NF_ACCEPT;
 838 +}
 839 +
 840 +static int imq_close(struct net_device *dev)
 841 +{
 842 +       netif_stop_queue(dev);
 843 +       return 0;
 844 +}
 845 +
 846 +static int imq_open(struct net_device *dev)
 847 +{
 848 +       netif_start_queue(dev);
 849 +       return 0;
 850 +}
 851 +
 852 +static const struct net_device_ops imq_netdev_ops = {
 853 +       .ndo_open               = imq_open,
 854 +       .ndo_stop               = imq_close,
 855 +       .ndo_start_xmit         = imq_dev_xmit,
 856 +       .ndo_get_stats          = imq_get_stats,
 857 +};
 858 +
 859 +static void imq_setup(struct net_device *dev)
 860 +{
 861 +       dev->netdev_ops         = &imq_netdev_ops;
 862 +       dev->type               = ARPHRD_VOID;
 863 +       dev->mtu                = 16000; /* too small? */
 864 +       dev->tx_queue_len       = 11000; /* too big? */
 865 +       dev->flags              = IFF_NOARP;
 866 +       dev->features           = NETIF_F_SG | NETIF_F_FRAGLIST |
 867 +                                 NETIF_F_GSO | NETIF_F_HW_CSUM |
 868 +                                 NETIF_F_HIGHDMA;
 869 +       dev->priv_flags         &= ~(IFF_XMIT_DST_RELEASE |
 870 +                                    IFF_TX_SKB_SHARING);
 871 +}
 872 +
 873 +static int imq_validate(struct nlattr *tb[], struct nlattr *data[])
 874 +{
 875 +       int ret = 0;
 876 +
 877 +       if (tb[IFLA_ADDRESS]) {
 878 +               if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) {
 879 +                       ret = -EINVAL;
 880 +                       goto end;
 881 +               }
 882 +               if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) {
 883 +                       ret = -EADDRNOTAVAIL;
 884 +                       goto end;
 885 +               }
 886 +       }
 887 +       return 0;
 888 +end:
 889 +       pr_warn("IMQ: imq_validate failed (%d)\n", ret);
 890 +       return ret;
 891 +}
 892 +
 893 +static struct rtnl_link_ops imq_link_ops __read_mostly = {
 894 +       .kind           = "imq",
 895 +       .priv_size      = 0,
 896 +       .setup          = imq_setup,
 897 +       .validate       = imq_validate,
 898 +};
 899 +
 900 +static const struct nf_queue_handler imq_nfqh = {
 901 +       .outfn = imq_nf_queue,
 902 +};
 903 +
 904 +static int __init imq_init_hooks(void)
 905 +{
 906 +       int ret;
 907 +
 908 +       nf_register_queue_imq_handler(&imq_nfqh);
 909 +
 910 +       ret = nf_register_hooks(imq_ops, ARRAY_SIZE(imq_ops));
 911 +       if (ret < 0)
 912 +               nf_unregister_queue_imq_handler();
 913 +
 914 +       return ret;
 915 +}
 916 +
 917 +static int __init imq_init_one(int index)
 918 +{
 919 +       struct net_device *dev;
 920 +       int ret;
 921 +
 922 +       dev = alloc_netdev_mq(0, "imq%d", NET_NAME_UNKNOWN, imq_setup, numqueues);
 923 +       if (!dev)
 924 +               return -ENOMEM;
 925 +
 926 +       ret = dev_alloc_name(dev, dev->name);
 927 +       if (ret < 0)
 928 +               goto fail;
 929 +
 930 +       dev->rtnl_link_ops = &imq_link_ops;
 931 +       ret = register_netdevice(dev);
 932 +       if (ret < 0)
 933 +               goto fail;
 934 +
 935 +       return 0;
 936 +fail:
 937 +       free_netdev(dev);
 938 +       return ret;
 939 +}
 940 +
 941 +static int __init imq_init_devs(void)
 942 +{
 943 +       int err, i;
 944 +
 945 +       if (numdevs < 1 || numdevs > IMQ_MAX_DEVS) {
 946 +               pr_err("IMQ: numdevs has to be betweed 1 and %u\n",
 947 +                      IMQ_MAX_DEVS);
 948 +               return -EINVAL;
 949 +       }
 950 +
 951 +       if (numqueues < 1 || numqueues > IMQ_MAX_QUEUES) {
 952 +               pr_err("IMQ: numqueues has to be betweed 1 and %u\n",
 953 +                      IMQ_MAX_QUEUES);
 954 +               return -EINVAL;
 955 +       }
 956 +
 957 +       get_random_bytes(&imq_hashrnd, sizeof(imq_hashrnd));
 958 +
 959 +       rtnl_lock();
 960 +       err = __rtnl_link_register(&imq_link_ops);
 961 +
 962 +       for (i = 0; i < numdevs && !err; i++)
 963 +               err = imq_init_one(i);
 964 +
 965 +       if (err) {
 966 +               __rtnl_link_unregister(&imq_link_ops);
 967 +               memset(imq_devs_cache, 0, sizeof(imq_devs_cache));
 968 +       }
 969 +       rtnl_unlock();
 970 +
 971 +       return err;
 972 +}
 973 +
 974 +static int __init imq_init_module(void)
 975 +{
 976 +       int err;
 977 +
 978 +#if defined(CONFIG_IMQ_NUM_DEVS)
 979 +       BUILD_BUG_ON(CONFIG_IMQ_NUM_DEVS > 16);
 980 +       BUILD_BUG_ON(CONFIG_IMQ_NUM_DEVS < 2);
 981 +       BUILD_BUG_ON(CONFIG_IMQ_NUM_DEVS - 1 > IMQ_F_IFMASK);
 982 +#endif
 983 +
 984 +       err = imq_init_devs();
 985 +       if (err) {
 986 +               pr_err("IMQ: Error trying imq_init_devs(net)\n");
 987 +               return err;
 988 +       }
 989 +
 990 +       err = imq_init_hooks();
 991 +       if (err) {
 992 +               pr_err(KERN_ERR "IMQ: Error trying imq_init_hooks()\n");
 993 +               rtnl_link_unregister(&imq_link_ops);
 994 +               memset(imq_devs_cache, 0, sizeof(imq_devs_cache));
 995 +               return err;
 996 +       }
 997 +
 998 +       pr_info("IMQ driver loaded successfully. (numdevs = %d, numqueues = %d, imq_dev_accurate_stats = %d)\n",
 999 +               numdevs, numqueues, imq_dev_accurate_stats);
1000 +
1001 +#if defined(CONFIG_IMQ_BEHAVIOR_BA) || defined(CONFIG_IMQ_BEHAVIOR_BB)
1002 +       pr_info("\tHooking IMQ before NAT on PREROUTING.\n");
1003 +#else
1004 +       pr_info("\tHooking IMQ after NAT on PREROUTING.\n");
1005 +#endif
1006 +#if defined(CONFIG_IMQ_BEHAVIOR_AB) || defined(CONFIG_IMQ_BEHAVIOR_BB)
1007 +       pr_info("\tHooking IMQ before NAT on POSTROUTING.\n");
1008 +#else
1009 +       pr_info("\tHooking IMQ after NAT on POSTROUTING.\n");
1010 +#endif
1011 +
1012 +       return 0;
1013 +}
1014 +
1015 +static void __exit imq_unhook(void)
1016 +{
1017 +       nf_unregister_hooks(imq_ops, ARRAY_SIZE(imq_ops));
1018 +       nf_unregister_queue_imq_handler();
1019 +}
1020 +
1021 +static void __exit imq_cleanup_devs(void)
1022 +{
1023 +       rtnl_link_unregister(&imq_link_ops);
1024 +       memset(imq_devs_cache, 0, sizeof(imq_devs_cache));
1025 +}
1026 +
1027 +static void __exit imq_exit_module(void)
1028 +{
1029 +       imq_unhook();
1030 +       imq_cleanup_devs();
1031 +       pr_info("IMQ driver unloaded successfully.\n");
1032 +}
1033 +
1034 +module_init(imq_init_module);
1035 +module_exit(imq_exit_module);
1036 +
1037 +module_param(numdevs, int, 0);
1038 +module_param(numqueues, int, 0);
1039 +module_param(imq_dev_accurate_stats, int, 0);
1040 +MODULE_PARM_DESC(numdevs, "number of IMQ devices (how many imq* devices will be created)");
1041 +MODULE_PARM_DESC(numqueues, "number of queues per IMQ device");
1042 +MODULE_PARM_DESC(imq_dev_accurate_stats, "Notify if need the accurate imq device stats");
1043 +
1044 +MODULE_AUTHOR("http://https://github.com/imq/linuximq");
1045 +MODULE_DESCRIPTION("Pseudo-driver for the intermediate queue device. See https://github.com/imq/linuximq/wiki for more information.");
1046 +MODULE_LICENSE("GPL");
1047 +MODULE_ALIAS_RTNL_LINK("imq");
1048 diff -urNp -x '*.orig' linux-4.4/include/linux/imq.h linux-4.4/include/linux/imq.h
1049 --- linux-4.4/include/linux/imq.h       1970-01-01 01:00:00.000000000 +0100
1050 +++ linux-4.4/include/linux/imq.h       2021-02-24 16:53:35.787510557 +0100
1051 @@ -0,0 +1,13 @@
1052 +#ifndef _IMQ_H
1053 +#define _IMQ_H
1054 +
1055 +/* IFMASK (16 device indexes, 0 to 15) and flag(s) fit in 5 bits */
1056 +#define IMQ_F_BITS     5
1057 +
1058 +#define IMQ_F_IFMASK   0x0f
1059 +#define IMQ_F_ENQUEUE  0x10
1060 +
1061 +#define IMQ_MAX_DEVS   (IMQ_F_IFMASK + 1)
1062 +
1063 +#endif /* _IMQ_H */
1064 +
1065 diff -urNp -x '*.orig' linux-4.4/include/linux/netdevice.h linux-4.4/include/linux/netdevice.h
1066 --- linux-4.4/include/linux/netdevice.h 2021-02-24 16:53:24.400485858 +0100
1067 +++ linux-4.4/include/linux/netdevice.h 2021-02-24 16:53:35.787510557 +0100
1068 @@ -3421,6 +3421,19 @@ static inline void netif_tx_unlock_bh(st
1069         }                                               \
1070  }
1071
1072 +#define HARD_TX_LOCK_BH(dev, txq) {           \
1073 +    if ((dev->features & NETIF_F_LLTX) == 0) {  \
1074 +        __netif_tx_lock_bh(txq);      \
1075 +    }                       \
1076 +}
1077 +
1078 +#define HARD_TX_UNLOCK_BH(dev, txq) {          \
1079 +    if ((dev->features & NETIF_F_LLTX) == 0) {  \
1080 +        __netif_tx_unlock_bh(txq);         \
1081 +    }                       \
1082 +}
1083 +
1084 +
1085  static inline void netif_tx_disable(struct net_device *dev)
1086  {
1087         unsigned int i;
1088 diff -urNp -x '*.orig' linux-4.4/include/linux/netfilter/xt_IMQ.h linux-4.4/include/linux/netfilter/xt_IMQ.h
1089 --- linux-4.4/include/linux/netfilter/xt_IMQ.h  1970-01-01 01:00:00.000000000 +0100
1090 +++ linux-4.4/include/linux/netfilter/xt_IMQ.h  2021-02-24 16:53:35.787510557 +0100
1091 @@ -0,0 +1,9 @@
1092 +#ifndef _XT_IMQ_H
1093 +#define _XT_IMQ_H
1094 +
1095 +struct xt_imq_info {
1096 +       unsigned int todev;     /* target imq device */
1097 +};
1098 +
1099 +#endif /* _XT_IMQ_H */
1100 +
1101 diff -urNp -x '*.orig' linux-4.4/include/linux/netfilter_ipv4/ipt_IMQ.h linux-4.4/include/linux/netfilter_ipv4/ipt_IMQ.h
1102 --- linux-4.4/include/linux/netfilter_ipv4/ipt_IMQ.h    1970-01-01 01:00:00.000000000 +0100
1103 +++ linux-4.4/include/linux/netfilter_ipv4/ipt_IMQ.h    2021-02-24 16:53:35.790843996 +0100
1104 @@ -0,0 +1,10 @@
1105 +#ifndef _IPT_IMQ_H
1106 +#define _IPT_IMQ_H
1107 +
1108 +/* Backwards compatibility for old userspace */
1109 +#include <linux/netfilter/xt_IMQ.h>
1110 +
1111 +#define ipt_imq_info xt_imq_info
1112 +
1113 +#endif /* _IPT_IMQ_H */
1114 +
1115 diff -urNp -x '*.orig' linux-4.4/include/linux/netfilter_ipv6/ip6t_IMQ.h linux-4.4/include/linux/netfilter_ipv6/ip6t_IMQ.h
1116 --- linux-4.4/include/linux/netfilter_ipv6/ip6t_IMQ.h   1970-01-01 01:00:00.000000000 +0100
1117 +++ linux-4.4/include/linux/netfilter_ipv6/ip6t_IMQ.h   2021-02-24 16:53:35.790843996 +0100
1118 @@ -0,0 +1,10 @@
1119 +#ifndef _IP6T_IMQ_H
1120 +#define _IP6T_IMQ_H
1121 +
1122 +/* Backwards compatibility for old userspace */
1123 +#include <linux/netfilter/xt_IMQ.h>
1124 +
1125 +#define ip6t_imq_info xt_imq_info
1126 +
1127 +#endif /* _IP6T_IMQ_H */
1128 +
1129 diff -urNp -x '*.orig' linux-4.4/include/linux/skbuff.h linux-4.4/include/linux/skbuff.h
1130 --- linux-4.4/include/linux/skbuff.h    2021-02-24 16:53:24.410486173 +0100
1131 +++ linux-4.4/include/linux/skbuff.h    2021-02-24 16:53:35.790843996 +0100
1132 @@ -38,6 +38,10 @@
1133  #include <linux/splice.h>
1134  #include <linux/in6.h>
1135  #include <net/flow.h>
1136 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1137 +#include <linux/imq.h>
1138 +#endif
1139 +
1140
1141  /* A. Checksumming of received packets by device.
1142   *
1143 @@ -573,6 +577,9 @@ struct sk_buff {
1144          * first. This is owned by whoever has the skb queued ATM.
1145          */
1146         char                    cb[48] __aligned(8);
1147 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1148 +       void                    *cb_next;
1149 +#endif
1150
1151         unsigned long           _skb_refdst;
1152         void                    (*destructor)(struct sk_buff *skb);
1153 @@ -582,6 +589,9 @@ struct sk_buff {
1154  #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
1155         struct nf_conntrack     *nfct;
1156  #endif
1157 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1158 +       struct nf_queue_entry   *nf_queue_entry;
1159 +#endif
1160  #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
1161         struct nf_bridge_info   *nf_bridge;
1162  #endif
1163 @@ -648,6 +658,9 @@ struct sk_buff {
1164         __u8                    inner_protocol_type:1;
1165         __u8                    remcsum_offload:1;
1166         /* 3 or 5 bit hole */
1167 +       #if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1168 +       __u8                    imq_flags:IMQ_F_BITS;
1169 +       #endif
1170
1171  #ifdef CONFIG_NET_SCHED
1172         __u16                   tc_index;       /* traffic control index */
1173 @@ -804,6 +817,12 @@ void kfree_skb_list(struct sk_buff *segs
1174  void skb_tx_error(struct sk_buff *skb);
1175  void consume_skb(struct sk_buff *skb);
1176  void  __kfree_skb(struct sk_buff *skb);
1177 +
1178 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1179 +int skb_save_cb(struct sk_buff *skb);
1180 +int skb_restore_cb(struct sk_buff *skb);
1181 +#endif
1182 +
1183  extern struct kmem_cache *skbuff_head_cache;
1184
1185  void kfree_skb_partial(struct sk_buff *skb, bool head_stolen);
1186 @@ -3443,6 +3462,10 @@ static inline void __nf_copy(struct sk_b
1187         if (copy)
1188                 dst->nfctinfo = src->nfctinfo;
1189  #endif
1190 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1191 +       dst->imq_flags = src->imq_flags;
1192 +       dst->nf_queue_entry = src->nf_queue_entry;
1193 +#endif
1194  #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
1195         dst->nf_bridge  = src->nf_bridge;
1196         nf_bridge_get(src->nf_bridge);
1197 diff -urNp -x '*.orig' linux-4.4/include/net/netfilter/nf_queue.h linux-4.4/include/net/netfilter/nf_queue.h
1198 --- linux-4.4/include/net/netfilter/nf_queue.h  2021-02-24 16:53:24.427153363 +0100
1199 +++ linux-4.4/include/net/netfilter/nf_queue.h  2021-02-24 16:53:35.790843996 +0100
1200 @@ -31,6 +31,12 @@ struct nf_queue_handler {
1201  void nf_register_queue_handler(struct net *net, const struct nf_queue_handler *qh);
1202  void nf_unregister_queue_handler(struct net *net);
1203  void nf_reinject(struct nf_queue_entry *entry, unsigned int verdict);
1204 +void nf_queue_entry_release_refs(struct nf_queue_entry *entry);
1205 +
1206 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1207 +void nf_register_queue_imq_handler(const struct nf_queue_handler *qh);
1208 +void nf_unregister_queue_imq_handler(void);
1209 +#endif
1210
1211  void nf_queue_entry_get_refs(struct nf_queue_entry *entry);
1212  void nf_queue_entry_release_refs(struct nf_queue_entry *entry);
1213 diff -urNp -x '*.orig' linux-4.4/include/net/pkt_sched.h linux-4.4/include/net/pkt_sched.h
1214 --- linux-4.4/include/net/pkt_sched.h   2016-01-11 00:01:32.000000000 +0100
1215 +++ linux-4.4/include/net/pkt_sched.h   2021-02-24 16:53:35.790843996 +0100
1216 @@ -104,6 +104,8 @@ int sch_direct_xmit(struct sk_buff *skb,
1217
1218  void __qdisc_run(struct Qdisc *q);
1219
1220 +struct sk_buff *qdisc_dequeue_skb(struct Qdisc *q, bool *validate);
1221 +
1222  static inline void qdisc_run(struct Qdisc *q)
1223  {
1224         if (qdisc_run_begin(q))
1225 diff -urNp -x '*.orig' linux-4.4/include/net/sch_generic.h linux-4.4/include/net/sch_generic.h
1226 --- linux-4.4/include/net/sch_generic.h 2021-02-24 16:53:24.430486801 +0100
1227 +++ linux-4.4/include/net/sch_generic.h 2021-02-24 16:53:35.790843996 +0100
1228 @@ -521,6 +521,12 @@ static inline int qdisc_enqueue(struct s
1229         return sch->enqueue(skb, sch);
1230  }
1231
1232 +static inline int qdisc_enqueue_root(struct sk_buff *skb, struct Qdisc *sch)
1233 +{
1234 +    qdisc_skb_cb(skb)->pkt_len = skb->len;
1235 +    return qdisc_enqueue(skb, sch) & NET_XMIT_MASK;
1236 +}
1237 +
1238  static inline bool qdisc_is_percpu_stats(const struct Qdisc *q)
1239  {
1240         return q->flags & TCQ_F_CPUSTATS;
1241 diff -urNp -x '*.orig' linux-4.4/include/uapi/linux/netfilter.h linux-4.4/include/uapi/linux/netfilter.h
1242 --- linux-4.4/include/uapi/linux/netfilter.h    2016-01-11 00:01:32.000000000 +0100
1243 +++ linux-4.4/include/uapi/linux/netfilter.h    2021-02-24 16:53:35.790843996 +0100
1244 @@ -14,7 +14,8 @@
1245  #define NF_QUEUE 3
1246  #define NF_REPEAT 4
1247  #define NF_STOP 5
1248 -#define NF_MAX_VERDICT NF_STOP
1249 +#define NF_IMQ_QUEUE 6
1250 +#define NF_MAX_VERDICT NF_IMQ_QUEUE
1251
1252  /* we overload the higher bits for encoding auxiliary data such as the queue
1253   * number or errno values. Not nice, but better than additional function
1254 diff -urNp -x '*.orig' linux-4.4/net/core/dev.c linux-4.4/net/core/dev.c
1255 --- linux-4.4/net/core/dev.c    2021-02-24 16:53:24.560490888 +0100
1256 +++ linux-4.4/net/core/dev.c    2021-02-24 16:53:35.790843996 +0100
1257 @@ -138,6 +138,9 @@
1258  #include <linux/errqueue.h>
1259  #include <linux/hrtimer.h>
1260  #include <linux/netfilter_ingress.h>
1261 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1262 +#include <linux/imq.h>
1263 +#endif
1264
1265  #include "net-sysfs.h"
1266
1267 @@ -2769,7 +2772,12 @@ static int xmit_one(struct sk_buff *skb,
1268         unsigned int len;
1269         int rc;
1270
1271 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1272 +       if ((!list_empty(&ptype_all) || !list_empty(&dev->ptype_all)) &&
1273 +               !(skb->imq_flags & IMQ_F_ENQUEUE))
1274 +#else
1275         if (!list_empty(&ptype_all) || !list_empty(&dev->ptype_all))
1276 +#endif
1277                 dev_queue_xmit_nit(skb, dev);
1278
1279         len = skb->len;
1280 @@ -2807,6 +2815,7 @@ out:
1281         *ret = rc;
1282         return skb;
1283  }
1284 +EXPORT_SYMBOL(dev_hard_start_xmit);
1285
1286  static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb,
1287                                           netdev_features_t features)
1288 diff -urNp -x '*.orig' linux-4.4/net/core/skbuff.c linux-4.4/net/core/skbuff.c
1289 --- linux-4.4/net/core/skbuff.c 2021-02-24 16:53:24.567157765 +0100
1290 +++ linux-4.4/net/core/skbuff.c 2021-02-24 16:53:35.790843996 +0100
1291 @@ -81,6 +81,87 @@ struct kmem_cache *skbuff_head_cache __r
1292  static struct kmem_cache *skbuff_fclone_cache __read_mostly;
1293  int sysctl_max_skb_frags __read_mostly = MAX_SKB_FRAGS;
1294  EXPORT_SYMBOL(sysctl_max_skb_frags);
1295 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1296 +static struct kmem_cache *skbuff_cb_store_cache __read_mostly;
1297 +#endif
1298 +
1299 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1300 +/* Control buffer save/restore for IMQ devices */
1301 +struct skb_cb_table {
1302 +       char                    cb[48] __aligned(8);
1303 +       void                    *cb_next;
1304 +       atomic_t                refcnt;
1305 +};
1306 +
1307 +static DEFINE_SPINLOCK(skb_cb_store_lock);
1308 +
1309 +int skb_save_cb(struct sk_buff *skb)
1310 +{
1311 +       struct skb_cb_table *next;
1312 +
1313 +       next = kmem_cache_alloc(skbuff_cb_store_cache, GFP_ATOMIC);
1314 +       if (!next)
1315 +               return -ENOMEM;
1316 +
1317 +       BUILD_BUG_ON(sizeof(skb->cb) != sizeof(next->cb));
1318 +
1319 +       memcpy(next->cb, skb->cb, sizeof(skb->cb));
1320 +       next->cb_next = skb->cb_next;
1321 +
1322 +       atomic_set(&next->refcnt, 1);
1323 +
1324 +       skb->cb_next = next;
1325 +       return 0;
1326 +}
1327 +EXPORT_SYMBOL(skb_save_cb);
1328 +
1329 +int skb_restore_cb(struct sk_buff *skb)
1330 +{
1331 +       struct skb_cb_table *next;
1332 +
1333 +       if (!skb->cb_next)
1334 +               return 0;
1335 +
1336 +       next = skb->cb_next;
1337 +
1338 +       BUILD_BUG_ON(sizeof(skb->cb) != sizeof(next->cb));
1339 +
1340 +       memcpy(skb->cb, next->cb, sizeof(skb->cb));
1341 +       skb->cb_next = next->cb_next;
1342 +
1343 +       spin_lock(&skb_cb_store_lock);
1344 +
1345 +       if (atomic_dec_and_test(&next->refcnt))
1346 +               kmem_cache_free(skbuff_cb_store_cache, next);
1347 +
1348 +       spin_unlock(&skb_cb_store_lock);
1349 +
1350 +       return 0;
1351 +}
1352 +EXPORT_SYMBOL(skb_restore_cb);
1353 +
1354 +static void skb_copy_stored_cb(struct sk_buff *   , const struct sk_buff *     ) __attribute__ ((unused));
1355 +static void skb_copy_stored_cb(struct sk_buff *new, const struct sk_buff *__old)
1356 +{
1357 +       struct skb_cb_table *next;
1358 +       struct sk_buff *old;
1359 +
1360 +       if (!__old->cb_next) {
1361 +               new->cb_next = NULL;
1362 +               return;
1363 +       }
1364 +
1365 +       spin_lock(&skb_cb_store_lock);
1366 +
1367 +       old = (struct sk_buff *)__old;
1368 +
1369 +       next = old->cb_next;
1370 +       atomic_inc(&next->refcnt);
1371 +       new->cb_next = next;
1372 +
1373 +       spin_unlock(&skb_cb_store_lock);
1374 +}
1375 +#endif
1376
1377  /**
1378   *     skb_panic - private function for out-of-line support
1379 @@ -658,6 +739,28 @@ static void skb_release_head_state(struc
1380                 WARN_ON(in_irq());
1381                 skb->destructor(skb);
1382         }
1383 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1384 +       /*
1385 +        * This should not happen. When it does, avoid memleak by restoring
1386 +        * the chain of cb-backups.
1387 +        */
1388 +       while (skb->cb_next != NULL) {
1389 +               if (net_ratelimit())
1390 +                       pr_warn("IMQ: kfree_skb: skb->cb_next: %08x\n",
1391 +                               (unsigned int)(uintptr_t)skb->cb_next);
1392 +
1393 +               skb_restore_cb(skb);
1394 +       }
1395 +       /*
1396 +        * This should not happen either, nf_queue_entry is nullified in
1397 +        * imq_dev_xmit(). If we have non-NULL nf_queue_entry then we are
1398 +        * leaking entry pointers, maybe memory. We don't know if this is
1399 +        * pointer to already freed memory, or should this be freed.
1400 +        * If this happens we need to add refcounting, etc for nf_queue_entry.
1401 +        */
1402 +       if (skb->nf_queue_entry && net_ratelimit())
1403 +               pr_warn("%s\n", "IMQ: kfree_skb: skb->nf_queue_entry != NULL");
1404 +#endif
1405  #if IS_ENABLED(CONFIG_NF_CONNTRACK)
1406         nf_conntrack_put(skb->nfct);
1407  #endif
1408 @@ -780,6 +883,10 @@ static void __copy_skb_header(struct sk_
1409         new->sp                 = secpath_get(old->sp);
1410  #endif
1411         __nf_copy(new, old, false);
1412 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1413 +       new->cb_next = NULL;
1414 +       /*skb_copy_stored_cb(new, old);*/
1415 +#endif
1416
1417         /* Note : this field could be in headers_start/headers_end section
1418          * It is not yet because we do not want to have a 16 bit hole
1419 @@ -3390,6 +3497,13 @@ void __init skb_init(void)
1420                                                 0,
1421                                                 SLAB_HWCACHE_ALIGN|SLAB_PANIC,
1422                                                 NULL);
1423 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1424 +       skbuff_cb_store_cache = kmem_cache_create("skbuff_cb_store_cache",
1425 +                                                 sizeof(struct skb_cb_table),
1426 +                                                 0,
1427 +                                                 SLAB_HWCACHE_ALIGN|SLAB_PANIC,
1428 +                                                 NULL);
1429 +#endif
1430  }
1431
1432  static int
1433 diff -urNp -x '*.orig' linux-4.4/net/ipv6/ip6_output.c linux-4.4/net/ipv6/ip6_output.c
1434 --- linux-4.4/net/ipv6/ip6_output.c     2021-02-24 16:53:24.600492146 +0100
1435 +++ linux-4.4/net/ipv6/ip6_output.c     2021-02-24 16:53:35.794177433 +0100
1436 @@ -65,9 +65,6 @@ static int ip6_finish_output2(struct net
1437         struct in6_addr *nexthop;
1438         int ret;
1439
1440 -       skb->protocol = htons(ETH_P_IPV6);
1441 -       skb->dev = dev;
1442 -
1443         if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) {
1444                 struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
1445
1446 @@ -142,6 +139,13 @@ int ip6_output(struct net *net, struct s
1447                 return 0;
1448         }
1449
1450 +       /*
1451 +       * IMQ-patch: moved setting skb->dev and skb->protocol from
1452 +       * ip6_finish_output2 to fix crashing at netif_skb_features().
1453 +       */
1454 +       skb->protocol = htons(ETH_P_IPV6);
1455 +       skb->dev = dev;
1456 +
1457         return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
1458                             net, sk, skb, NULL, dev,
1459                             ip6_finish_output,
1460 diff -urNp -x '*.orig' linux-4.4/net/netfilter/Kconfig linux-4.4/net/netfilter/Kconfig
1461 --- linux-4.4/net/netfilter/Kconfig     2021-02-24 16:53:25.017171913 +0100
1462 +++ linux-4.4/net/netfilter/Kconfig     2021-02-24 16:53:35.794177433 +0100
1463 @@ -785,6 +785,18 @@ config NETFILTER_XT_TARGET_LOG
1464
1465           To compile it as a module, choose M here.  If unsure, say N.
1466
1467 +config NETFILTER_XT_TARGET_IMQ
1468 +        tristate '"IMQ" target support'
1469 +       depends on NETFILTER_XTABLES
1470 +       depends on IP_NF_MANGLE || IP6_NF_MANGLE
1471 +       select IMQ
1472 +       default m if NETFILTER_ADVANCED=n
1473 +        help
1474 +          This option adds a `IMQ' target which is used to specify if and
1475 +          to which imq device packets should get enqueued/dequeued.
1476 +
1477 +          To compile it as a module, choose M here.  If unsure, say N.
1478 +
1479  config NETFILTER_XT_TARGET_MARK
1480         tristate '"MARK" target support'
1481         depends on NETFILTER_ADVANCED
1482 diff -urNp -x '*.orig' linux-4.4/net/netfilter/Makefile linux-4.4/net/netfilter/Makefile
1483 --- linux-4.4/net/netfilter/Makefile    2021-02-24 16:53:25.017171913 +0100
1484 +++ linux-4.4/net/netfilter/Makefile    2021-02-24 16:53:35.794177433 +0100
1485 @@ -108,6 +108,7 @@ obj-$(CONFIG_NETFILTER_XT_TARGET_CT) +=
1486  obj-$(CONFIG_NETFILTER_XT_TARGET_DSCP) += xt_DSCP.o
1487  obj-$(CONFIG_NETFILTER_XT_TARGET_HL) += xt_HL.o
1488  obj-$(CONFIG_NETFILTER_XT_TARGET_HMARK) += xt_HMARK.o
1489 +obj-$(CONFIG_NETFILTER_XT_TARGET_IMQ) += xt_IMQ.o
1490  obj-$(CONFIG_NETFILTER_XT_TARGET_LED) += xt_LED.o
1491  obj-$(CONFIG_NETFILTER_XT_TARGET_LOG) += xt_LOG.o
1492  obj-$(CONFIG_NETFILTER_XT_TARGET_NETMAP) += xt_NETMAP.o
1493 diff -urNp -x '*.orig' linux-4.4/net/netfilter/core.c linux-4.4/net/netfilter/core.c
1494 --- linux-4.4/net/netfilter/core.c      2016-01-11 00:01:32.000000000 +0100
1495 +++ linux-4.4/net/netfilter/core.c      2021-02-24 16:53:35.794177433 +0100
1496 @@ -311,9 +311,11 @@ next_hook:
1497                 ret = NF_DROP_GETERR(verdict);
1498                 if (ret == 0)
1499                         ret = -EPERM;
1500 -       } else if ((verdict & NF_VERDICT_MASK) == NF_QUEUE) {
1501 +       } else if ((verdict & NF_VERDICT_MASK) == NF_QUEUE ||
1502 +               (verdict & NF_VERDICT_MASK) == NF_IMQ_QUEUE) {
1503                 int err = nf_queue(skb, elem, state,
1504 -                                  verdict >> NF_VERDICT_QBITS);
1505 +                                  verdict >> NF_VERDICT_QBITS,
1506 +                                 verdict & NF_VERDICT_MASK);
1507                 if (err < 0) {
1508                         if (err == -ESRCH &&
1509                            (verdict & NF_VERDICT_FLAG_QUEUE_BYPASS))
1510 diff -urNp -x '*.orig' linux-4.4/net/netfilter/nf_internals.h linux-4.4/net/netfilter/nf_internals.h
1511 --- linux-4.4/net/netfilter/nf_internals.h      2016-01-11 00:01:32.000000000 +0100
1512 +++ linux-4.4/net/netfilter/nf_internals.h      2021-02-24 16:53:35.794177433 +0100
1513 @@ -18,7 +18,7 @@ unsigned int nf_iterate(struct list_head
1514
1515  /* nf_queue.c */
1516  int nf_queue(struct sk_buff *skb, struct nf_hook_ops *elem,
1517 -            struct nf_hook_state *state, unsigned int queuenum);
1518 +            struct nf_hook_state *state, unsigned int queuenum, unsigned int queuetype);
1519  void nf_queue_nf_hook_drop(struct net *net, struct nf_hook_ops *ops);
1520  int __init netfilter_queue_init(void);
1521
1522 diff -urNp -x '*.orig' linux-4.4/net/netfilter/nf_queue.c linux-4.4/net/netfilter/nf_queue.c
1523 --- linux-4.4/net/netfilter/nf_queue.c  2021-02-24 16:53:24.633826528 +0100
1524 +++ linux-4.4/net/netfilter/nf_queue.c  2021-02-24 16:53:35.794177433 +0100
1525 @@ -27,6 +27,23 @@
1526   * receives, no matter what.
1527   */
1528
1529 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1530 +static const struct nf_queue_handler __rcu *queue_imq_handler __read_mostly;
1531 +
1532 +void nf_register_queue_imq_handler(const struct nf_queue_handler *qh)
1533 +{
1534 +       rcu_assign_pointer(queue_imq_handler, qh);
1535 +}
1536 +EXPORT_SYMBOL_GPL(nf_register_queue_imq_handler);
1537 +
1538 +void nf_unregister_queue_imq_handler(void)
1539 +{
1540 +       RCU_INIT_POINTER(queue_imq_handler, NULL);
1541 +       synchronize_rcu();
1542 +}
1543 +EXPORT_SYMBOL_GPL(nf_unregister_queue_imq_handler);
1544 +#endif
1545 +
1546  /* return EBUSY when somebody else is registered, return EEXIST if the
1547   * same handler is registered, return 0 in case of success. */
1548  void nf_register_queue_handler(struct net *net, const struct nf_queue_handler *qh)
1549 @@ -114,7 +131,8 @@ void nf_queue_nf_hook_drop(struct net *n
1550  int nf_queue(struct sk_buff *skb,
1551              struct nf_hook_ops *elem,
1552              struct nf_hook_state *state,
1553 -            unsigned int queuenum)
1554 +            unsigned int queuenum,
1555 +                unsigned int queuetype)
1556  {
1557         int status = -ENOENT;
1558         struct nf_queue_entry *entry = NULL;
1559 @@ -123,7 +141,17 @@ int nf_queue(struct sk_buff *skb,
1560         struct net *net = state->net;
1561
1562         /* QUEUE == DROP if no one is waiting, to be safe. */
1563 -       qh = rcu_dereference(net->nf.queue_handler);
1564 +       if (queuetype == NF_IMQ_QUEUE) {
1565 +#if defined(CONFIG_IMQ) || defined(CONFIG_IMQ_MODULE)
1566 +               qh = rcu_dereference(queue_imq_handler);
1567 +#else
1568 +               BUG();
1569 +               goto err_unlock;
1570 +#endif
1571 +       } else {
1572 +               qh = rcu_dereference(net->nf.queue_handler);
1573 +       }
1574 +
1575         if (!qh) {
1576                 status = -ESRCH;
1577                 goto err;
1578 @@ -198,8 +226,10 @@ void nf_reinject(struct nf_queue_entry *
1579                 local_bh_enable();
1580                 break;
1581         case NF_QUEUE:
1582 +       case NF_IMQ_QUEUE:
1583                 err = nf_queue(skb, elem, &entry->state,
1584 -                              verdict >> NF_VERDICT_QBITS);
1585 +                              verdict >> NF_VERDICT_QBITS,
1586 +                                  verdict & NF_VERDICT_MASK);
1587                 if (err < 0) {
1588                         if (err == -ESRCH &&
1589                            (verdict & NF_VERDICT_FLAG_QUEUE_BYPASS))
1590 diff -urNp -x '*.orig' linux-4.4/net/netfilter/xt_IMQ.c linux-4.4/net/netfilter/xt_IMQ.c
1591 --- linux-4.4/net/netfilter/xt_IMQ.c    1970-01-01 01:00:00.000000000 +0100
1592 +++ linux-4.4/net/netfilter/xt_IMQ.c    2021-02-24 16:53:35.794177433 +0100
1593 @@ -0,0 +1,72 @@
1594 +/*
1595 + * This target marks packets to be enqueued to an imq device
1596 + */
1597 +#include <linux/module.h>
1598 +#include <linux/skbuff.h>
1599 +#include <linux/netfilter/x_tables.h>
1600 +#include <linux/netfilter/xt_IMQ.h>
1601 +#include <linux/imq.h>
1602 +
1603 +static unsigned int imq_target(struct sk_buff *pskb,
1604 +                               const struct xt_action_param *par)
1605 +{
1606 +       const struct xt_imq_info *mr = par->targinfo;
1607 +
1608 +       pskb->imq_flags = (mr->todev & IMQ_F_IFMASK) | IMQ_F_ENQUEUE;
1609 +
1610 +       return XT_CONTINUE;
1611 +}
1612 +
1613 +static int imq_checkentry(const struct xt_tgchk_param *par)
1614 +{
1615 +       struct xt_imq_info *mr = par->targinfo;
1616 +
1617 +       if (mr->todev > IMQ_MAX_DEVS - 1) {
1618 +               pr_warn("IMQ: invalid device specified, highest is %u\n",
1619 +                       IMQ_MAX_DEVS - 1);
1620 +               return -EINVAL;
1621 +       }
1622 +
1623 +       return 0;
1624 +}
1625 +
1626 +static struct xt_target xt_imq_reg[] __read_mostly = {
1627 +       {
1628 +               .name           = "IMQ",
1629 +               .family         = AF_INET,
1630 +               .checkentry     = imq_checkentry,
1631 +               .target         = imq_target,
1632 +               .targetsize     = sizeof(struct xt_imq_info),
1633 +               .table          = "mangle",
1634 +               .me             = THIS_MODULE
1635 +       },
1636 +       {
1637 +               .name           = "IMQ",
1638 +               .family         = AF_INET6,
1639 +               .checkentry     = imq_checkentry,
1640 +               .target         = imq_target,
1641 +               .targetsize     = sizeof(struct xt_imq_info),
1642 +               .table          = "mangle",
1643 +               .me             = THIS_MODULE
1644 +       },
1645 +};
1646 +
1647 +static int __init imq_init(void)
1648 +{
1649 +       return xt_register_targets(xt_imq_reg, ARRAY_SIZE(xt_imq_reg));
1650 +}
1651 +
1652 +static void __exit imq_fini(void)
1653 +{
1654 +       xt_unregister_targets(xt_imq_reg, ARRAY_SIZE(xt_imq_reg));
1655 +}
1656 +
1657 +module_init(imq_init);
1658 +module_exit(imq_fini);
1659 +
1660 +MODULE_AUTHOR("http://https://github.com/imq/linuximq");
1661 +MODULE_DESCRIPTION("Pseudo-driver for the intermediate queue device. See https://github.com/imq/linuximq/wiki for more information.");
1662 +MODULE_LICENSE("GPL");
1663 +MODULE_ALIAS("ipt_IMQ");
1664 +MODULE_ALIAS("ip6t_IMQ");
1665 +
1666 diff -urNp -x '*.orig' linux-4.4/net/sched/sch_generic.c linux-4.4/net/sched/sch_generic.c
1667 --- linux-4.4/net/sched/sch_generic.c   2021-02-24 16:53:24.657160594 +0100
1668 +++ linux-4.4/net/sched/sch_generic.c   2021-02-24 16:53:35.794177433 +0100
1669 @@ -110,6 +110,14 @@ static struct sk_buff *dequeue_skb(struc
1670         return skb;
1671  }
1672
1673 +struct sk_buff *qdisc_dequeue_skb(struct Qdisc *q, bool *validate)
1674 +{
1675 +       int packets;
1676 +
1677 +       return dequeue_skb(q, validate, &packets);
1678 +}
1679 +EXPORT_SYMBOL(qdisc_dequeue_skb);
1680 +
1681  static inline int handle_dev_cpu_collision(struct sk_buff *skb,
1682                                            struct netdev_queue *dev_queue,
1683                                            struct Qdisc *q)