target/linux/generic/patches-4.4/645-bridge_multicast_to_unicast.patch

   1 From: Felix Fietkau <nbd@openwrt.org>
   2 Subject: [PATCH] bridge: multicast to unicast
   3
   4 Implement optinal multicast->unicast conversion for igmp snooping
   5 ---
   6 --- a/include/linux/if_bridge.h
   7 +++ b/include/linux/if_bridge.h
   8 @@ -46,6 +46,7 @@ struct br_ip_list {
   9  #define BR_LEARNING_SYNC       BIT(9)
  10  #define BR_PROXYARP_WIFI       BIT(10)
  11  #define BR_ISOLATE_MODE        BIT(11)
  12 +#define BR_MULTICAST_TO_UCAST  BIT(12)
  13
  14  /* values as per ieee8021QBridgeFdbAgingTime */
  15  #define BR_MIN_AGEING_TIME     (10 * HZ)
  16 --- a/net/bridge/br_multicast.c
  17 +++ b/net/bridge/br_multicast.c
  18 @@ -42,12 +42,13 @@ static void br_multicast_add_router(stru
  19  static void br_ip4_multicast_leave_group(struct net_bridge *br,
  20                                          struct net_bridge_port *port,
  21                                          __be32 group,
  22 -                                        __u16 vid);
  23 +                                        __u16 vid,
  24 +                                        const unsigned char *src);
  25  #if IS_ENABLED(CONFIG_IPV6)
  26  static void br_ip6_multicast_leave_group(struct net_bridge *br,
  27                                          struct net_bridge_port *port,
  28                                          const struct in6_addr *group,
  29 -                                        __u16 vid);
  30 +                                        __u16 vid, const unsigned char *src);
  31  #endif
  32  unsigned int br_mdb_rehash_seq;
  33
  34 @@ -649,7 +650,8 @@ struct net_bridge_port_group *br_multica
  35                         struct net_bridge_port *port,
  36                         struct br_ip *group,
  37                         struct net_bridge_port_group __rcu *next,
  38 -                       unsigned char state)
  39 +                       unsigned char state,
  40 +                       const unsigned char *src)
  41  {
  42         struct net_bridge_port_group *p;
  43
  44 @@ -664,12 +666,33 @@ struct net_bridge_port_group *br_multica
  45         hlist_add_head(&p->mglist, &port->mglist);
  46         setup_timer(&p->timer, br_multicast_port_group_expired,
  47                     (unsigned long)p);
  48 +       if ((port->flags & BR_MULTICAST_TO_UCAST) && src) {
  49 +               memcpy(p->eth_addr, src, ETH_ALEN);
  50 +               p->unicast = true;
  51 +       }
  52         return p;
  53  }
  54
  55 +static bool br_port_group_equal(struct net_bridge_port_group *p,
  56 +                               struct net_bridge_port *port,
  57 +                               const unsigned char *src)
  58 +{
  59 +       if (p->port != port)
  60 +               return false;
  61 +
  62 +       if (!p->unicast)
  63 +               return true;
  64 +
  65 +       if (!src)
  66 +               return false;
  67 +
  68 +       return ether_addr_equal(src, p->eth_addr);
  69 +}
  70 +
  71  static int br_multicast_add_group(struct net_bridge *br,
  72                                   struct net_bridge_port *port,
  73 -                                 struct br_ip *group)
  74 +                                 struct br_ip *group,
  75 +                                 const unsigned char *src)
  76  {
  77         struct net_bridge_mdb_entry *mp;
  78         struct net_bridge_port_group *p;
  79 @@ -696,13 +719,13 @@ static int br_multicast_add_group(struct
  80         for (pp = &mp->ports;
  81              (p = mlock_dereference(*pp, br)) != NULL;
  82              pp = &p->next) {
  83 -               if (p->port == port)
  84 +               if (br_port_group_equal(p, port, src))
  85                         goto found;
  86                 if ((unsigned long)p->port < (unsigned long)port)
  87                         break;
  88         }
  89
  90 -       p = br_multicast_new_port_group(port, group, *pp, MDB_TEMPORARY);
  91 +       p = br_multicast_new_port_group(port, group, *pp, MDB_TEMPORARY, src);
  92         if (unlikely(!p))
  93                 goto err;
  94         rcu_assign_pointer(*pp, p);
  95 @@ -721,7 +744,7 @@ err:
  96  static int br_ip4_multicast_add_group(struct net_bridge *br,
  97                                       struct net_bridge_port *port,
  98                                       __be32 group,
  99 -                                     __u16 vid)
 100 +                                     __u16 vid, const unsigned char *src)
 101  {
 102         struct br_ip br_group;
 103
 104 @@ -732,14 +755,14 @@ static int br_ip4_multicast_add_group(st
 105         br_group.proto = htons(ETH_P_IP);
 106         br_group.vid = vid;
 107
 108 -       return br_multicast_add_group(br, port, &br_group);
 109 +       return br_multicast_add_group(br, port, &br_group, src);
 110  }
 111
 112  #if IS_ENABLED(CONFIG_IPV6)
 113  static int br_ip6_multicast_add_group(struct net_bridge *br,
 114                                       struct net_bridge_port *port,
 115                                       const struct in6_addr *group,
 116 -                                     __u16 vid)
 117 +                                     __u16 vid, const unsigned char *src)
 118  {
 119         struct br_ip br_group;
 120
 121 @@ -750,7 +773,7 @@ static int br_ip6_multicast_add_group(st
 122         br_group.proto = htons(ETH_P_IPV6);
 123         br_group.vid = vid;
 124
 125 -       return br_multicast_add_group(br, port, &br_group);
 126 +       return br_multicast_add_group(br, port, &br_group, src);
 127  }
 128  #endif
 129
 130 @@ -995,6 +1018,7 @@ static int br_ip4_multicast_igmp3_report
 131                                          struct sk_buff *skb,
 132                                          u16 vid)
 133  {
 134 +       const unsigned char *src;
 135         struct igmpv3_report *ih;
 136         struct igmpv3_grec *grec;
 137         int i;
 138 @@ -1035,12 +1059,13 @@ static int br_ip4_multicast_igmp3_report
 139                         continue;
 140                 }
 141
 142 +               src = eth_hdr(skb)->h_source;
 143                 if ((type == IGMPV3_CHANGE_TO_INCLUDE ||
 144                      type == IGMPV3_MODE_IS_INCLUDE) &&
 145                     ntohs(grec->grec_nsrcs) == 0) {
 146 -                       br_ip4_multicast_leave_group(br, port, group, vid);
 147 +                       br_ip4_multicast_leave_group(br, port, group, vid, src);
 148                 } else {
 149 -                       err = br_ip4_multicast_add_group(br, port, group, vid);
 150 +                       err = br_ip4_multicast_add_group(br, port, group, vid, src);
 151                         if (err)
 152                                 break;
 153                 }
 154 @@ -1055,6 +1080,7 @@ static int br_ip6_multicast_mld2_report(
 155                                         struct sk_buff *skb,
 156                                         u16 vid)
 157  {
 158 +       const unsigned char *src = eth_hdr(skb)->h_source;
 159         struct icmp6hdr *icmp6h;
 160         struct mld2_grec *grec;
 161         int i;
 162 @@ -1106,10 +1132,10 @@ static int br_ip6_multicast_mld2_report(
 163                      grec->grec_type == MLD2_MODE_IS_INCLUDE) &&
 164                     ntohs(*nsrcs) == 0) {
 165                         br_ip6_multicast_leave_group(br, port, &grec->grec_mca,
 166 -                                                    vid);
 167 +                                                    vid, src);
 168                 } else {
 169                         err = br_ip6_multicast_add_group(br, port,
 170 -                                                        &grec->grec_mca, vid);
 171 +                                                        &grec->grec_mca, vid, src);
 172                         if (!err)
 173                                 break;
 174                 }
 175 @@ -1422,7 +1448,8 @@ br_multicast_leave_group(struct net_brid
 176                          struct net_bridge_port *port,
 177                          struct br_ip *group,
 178                          struct bridge_mcast_other_query *other_query,
 179 -                        struct bridge_mcast_own_query *own_query)
 180 +                        struct bridge_mcast_own_query *own_query,
 181 +                        const unsigned char *src)
 182  {
 183         struct net_bridge_mdb_htable *mdb;
 184         struct net_bridge_mdb_entry *mp;
 185 @@ -1446,7 +1473,7 @@ br_multicast_leave_group(struct net_brid
 186                 for (pp = &mp->ports;
 187                      (p = mlock_dereference(*pp, br)) != NULL;
 188                      pp = &p->next) {
 189 -                       if (p->port != port)
 190 +                       if (!br_port_group_equal(p, port, src))
 191                                 continue;
 192
 193                         rcu_assign_pointer(*pp, p->next);
 194 @@ -1509,7 +1536,7 @@ br_multicast_leave_group(struct net_brid
 195         for (p = mlock_dereference(mp->ports, br);
 196              p != NULL;
 197              p = mlock_dereference(p->next, br)) {
 198 -               if (p->port != port)
 199 +               if (!br_port_group_equal(p, port, src))
 200                         continue;
 201
 202                 if (!hlist_unhashed(&p->mglist) &&
 203 @@ -1527,8 +1554,8 @@ out:
 204
 205  static void br_ip4_multicast_leave_group(struct net_bridge *br,
 206                                          struct net_bridge_port *port,
 207 -                                        __be32 group,
 208 -                                        __u16 vid)
 209 +                                        __be32 group, __u16 vid,
 210 +                                        const unsigned char *src)
 211  {
 212         struct br_ip br_group;
 213         struct bridge_mcast_own_query *own_query;
 214 @@ -1543,14 +1570,14 @@ static void br_ip4_multicast_leave_group
 215         br_group.vid = vid;
 216
 217         br_multicast_leave_group(br, port, &br_group, &br->ip4_other_query,
 218 -                                own_query);
 219 +                                own_query, src);
 220  }
 221
 222  #if IS_ENABLED(CONFIG_IPV6)
 223  static void br_ip6_multicast_leave_group(struct net_bridge *br,
 224                                          struct net_bridge_port *port,
 225                                          const struct in6_addr *group,
 226 -                                        __u16 vid)
 227 +                                        __u16 vid, const unsigned char *src)
 228  {
 229         struct br_ip br_group;
 230         struct bridge_mcast_own_query *own_query;
 231 @@ -1565,7 +1592,7 @@ static void br_ip6_multicast_leave_group
 232         br_group.vid = vid;
 233
 234         br_multicast_leave_group(br, port, &br_group, &br->ip6_other_query,
 235 -                                own_query);
 236 +                                own_query, src);
 237  }
 238  #endif
 239
 240 @@ -1574,6 +1601,7 @@ static int br_multicast_ipv4_rcv(struct
 241                                  struct sk_buff *skb,
 242                                  u16 vid)
 243  {
 244 +       const unsigned char *src;
 245         struct sk_buff *skb_trimmed = NULL;
 246         struct igmphdr *ih;
 247         int err;
 248 @@ -1590,12 +1618,13 @@ static int br_multicast_ipv4_rcv(struct
 249
 250         BR_INPUT_SKB_CB(skb)->igmp = 1;
 251         ih = igmp_hdr(skb);
 252 +       src = eth_hdr(skb)->h_source;
 253
 254         switch (ih->type) {
 255         case IGMP_HOST_MEMBERSHIP_REPORT:
 256         case IGMPV2_HOST_MEMBERSHIP_REPORT:
 257                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
 258 -               err = br_ip4_multicast_add_group(br, port, ih->group, vid);
 259 +               err = br_ip4_multicast_add_group(br, port, ih->group, vid, src);
 260                 break;
 261         case IGMPV3_HOST_MEMBERSHIP_REPORT:
 262                 err = br_ip4_multicast_igmp3_report(br, port, skb_trimmed, vid);
 263 @@ -1604,7 +1633,7 @@ static int br_multicast_ipv4_rcv(struct
 264                 err = br_ip4_multicast_query(br, port, skb_trimmed, vid);
 265                 break;
 266         case IGMP_HOST_LEAVE_MESSAGE:
 267 -               br_ip4_multicast_leave_group(br, port, ih->group, vid);
 268 +               br_ip4_multicast_leave_group(br, port, ih->group, vid, src);
 269                 break;
 270         }
 271
 272 @@ -1620,6 +1649,7 @@ static int br_multicast_ipv6_rcv(struct
 273                                  struct sk_buff *skb,
 274                                  u16 vid)
 275  {
 276 +       const unsigned char *src;
 277         struct sk_buff *skb_trimmed = NULL;
 278         struct mld_msg *mld;
 279         int err;
 280 @@ -1639,8 +1669,9 @@ static int br_multicast_ipv6_rcv(struct
 281
 282         switch (mld->mld_type) {
 283         case ICMPV6_MGM_REPORT:
 284 +               src = eth_hdr(skb)->h_source;
 285                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
 286 -               err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid);
 287 +               err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid, src);
 288                 break;
 289         case ICMPV6_MLD2_REPORT:
 290                 err = br_ip6_multicast_mld2_report(br, port, skb_trimmed, vid);
 291 @@ -1649,7 +1680,8 @@ static int br_multicast_ipv6_rcv(struct
 292                 err = br_ip6_multicast_query(br, port, skb_trimmed, vid);
 293                 break;
 294         case ICMPV6_MGM_REDUCTION:
 295 -               br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid);
 296 +               src = eth_hdr(skb)->h_source;
 297 +               br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid, src);
 298                 break;
 299         }
 300
 301 --- a/net/bridge/br_private.h
 302 +++ b/net/bridge/br_private.h
 303 @@ -158,6 +158,9 @@ struct net_bridge_port_group {
 304         struct timer_list               timer;
 305         struct br_ip                    addr;
 306         unsigned char                   state;
 307 +
 308 +       unsigned char                   eth_addr[ETH_ALEN];
 309 +       bool                            unicast;
 310  };
 311
 312  struct net_bridge_mdb_entry
 313 @@ -554,7 +557,8 @@ void br_multicast_free_pg(struct rcu_hea
 314  struct net_bridge_port_group *
 315  br_multicast_new_port_group(struct net_bridge_port *port, struct br_ip *group,
 316                             struct net_bridge_port_group __rcu *next,
 317 -                           unsigned char state);
 318 +                           unsigned char state,
 319 +                      const unsigned char *src);
 320  void br_mdb_init(void);
 321  void br_mdb_uninit(void);
 322  void br_mdb_notify(struct net_device *dev, struct net_bridge_port *port,
 323 --- a/net/bridge/br_mdb.c
 324 +++ b/net/bridge/br_mdb.c
 325 @@ -416,7 +416,7 @@ static int br_mdb_add_group(struct net_b
 326                         break;
 327         }
 328
 329 -       p = br_multicast_new_port_group(port, group, *pp, state);
 330 +       p = br_multicast_new_port_group(port, group, *pp, state, NULL);
 331         if (unlikely(!p))
 332                 return -ENOMEM;
 333         rcu_assign_pointer(*pp, p);
 334 --- a/net/bridge/br_forward.c
 335 +++ b/net/bridge/br_forward.c
 336 @@ -192,6 +192,34 @@ out:
 337         return p;
 338  }
 339
 340 +static struct net_bridge_port *maybe_deliver_addr(
 341 +       struct net_bridge_port *prev, struct net_bridge_port *p,
 342 +       struct sk_buff *skb, const unsigned char *addr,
 343 +       void (*__packet_hook)(const struct net_bridge_port *p,
 344 +                             struct sk_buff *skb))
 345 +{
 346 +       struct net_device *dev = BR_INPUT_SKB_CB(skb)->brdev;
 347 +       const unsigned char *src = eth_hdr(skb)->h_source;
 348 +
 349 +       if (!should_deliver(p, skb))
 350 +               return prev;
 351 +
 352 +       /* Even with hairpin, no soliloquies - prevent breaking IPv6 DAD */
 353 +       if (skb->dev == p->dev && ether_addr_equal(src, addr))
 354 +               return prev;
 355 +
 356 +       skb = skb_copy(skb, GFP_ATOMIC);
 357 +       if (!skb) {
 358 +               dev->stats.tx_dropped++;
 359 +               return prev;
 360 +       }
 361 +
 362 +       memcpy(eth_hdr(skb)->h_dest, addr, ETH_ALEN);
 363 +       __packet_hook(p, skb);
 364 +
 365 +       return prev;
 366 +}
 367 +
 368  /* called under bridge lock */
 369  static void br_flood(struct net_bridge *br, struct sk_buff *skb,
 370                      struct sk_buff *skb0,
 371 @@ -264,6 +292,7 @@ static void br_multicast_flood(struct ne
 372         struct net_bridge_port *prev = NULL;
 373         struct net_bridge_port_group *p;
 374         struct hlist_node *rp;
 375 +       const unsigned char *addr;
 376
 377         rp = rcu_dereference(hlist_first_rcu(&br->router_list));
 378         p = mdst ? rcu_dereference(mdst->ports) : NULL;
 379 @@ -274,10 +303,19 @@ static void br_multicast_flood(struct ne
 380                 rport = rp ? hlist_entry(rp, struct net_bridge_port, rlist) :
 381                              NULL;
 382
 383 -               port = (unsigned long)lport > (unsigned long)rport ?
 384 -                      lport : rport;
 385 -
 386 -               prev = maybe_deliver(prev, port, skb, __packet_hook);
 387 +               if ((unsigned long)lport > (unsigned long)rport) {
 388 +                       port = lport;
 389 +                       addr = p->unicast ? p->eth_addr : NULL;
 390 +               } else {
 391 +                       port = rport;
 392 +                       addr = NULL;
 393 +               }
 394 +
 395 +               if (addr)
 396 +                       prev = maybe_deliver_addr(prev, port, skb, addr,
 397 +                                                 __packet_hook);
 398 +               else
 399 +                       prev = maybe_deliver(prev, port, skb, __packet_hook);
 400                 if (IS_ERR(prev))
 401                         goto out;
 402
 403 --- a/net/bridge/br_sysfs_if.c
 404 +++ b/net/bridge/br_sysfs_if.c
 405 @@ -204,6 +204,7 @@ static BRPORT_ATTR(multicast_router, S_I
 406                    store_multicast_router);
 407
 408  BRPORT_ATTR_FLAG(multicast_fast_leave, BR_MULTICAST_FAST_LEAVE);
 409 +BRPORT_ATTR_FLAG(multicast_to_unicast, BR_MULTICAST_TO_UCAST);
 410  #endif
 411
 412  static const struct brport_attribute *brport_attrs[] = {
 413 @@ -230,6 +231,7 @@ static const struct brport_attribute *br
 414  #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
 415         &brport_attr_multicast_router,
 416         &brport_attr_multicast_fast_leave,
 417 +       &brport_attr_multicast_to_unicast,
 418  #endif
 419         &brport_attr_proxyarp,
 420         &brport_attr_proxyarp_wifi,