target/linux/generic/patches-4.1/645-bridge_multicast_to_unicast.patch

   1 From: Felix Fietkau <nbd@nbd.name>
   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  extern void brioctl_set(int (*ioctl_hook)(struct net *, unsigned int, void __user *));
  15
  16 --- a/net/bridge/br_multicast.c
  17 +++ b/net/bridge/br_multicast.c
  18 @@ -635,7 +635,8 @@ struct net_bridge_port_group *br_multica
  19                         struct net_bridge_port *port,
  20                         struct br_ip *group,
  21                         struct net_bridge_port_group __rcu *next,
  22 -                       unsigned char state)
  23 +                       unsigned char state,
  24 +                       const unsigned char *src)
  25  {
  26         struct net_bridge_port_group *p;
  27
  28 @@ -650,12 +651,33 @@ struct net_bridge_port_group *br_multica
  29         hlist_add_head(&p->mglist, &port->mglist);
  30         setup_timer(&p->timer, br_multicast_port_group_expired,
  31                     (unsigned long)p);
  32 +       if ((port->flags & BR_MULTICAST_TO_UCAST) && src) {
  33 +               memcpy(p->eth_addr, src, ETH_ALEN);
  34 +               p->unicast = true;
  35 +       }
  36         return p;
  37  }
  38
  39 +static bool br_port_group_equal(struct net_bridge_port_group *p,
  40 +                               struct net_bridge_port *port,
  41 +                               const unsigned char *src)
  42 +{
  43 +       if (p->port != port)
  44 +               return false;
  45 +
  46 +       if (!p->unicast)
  47 +               return true;
  48 +
  49 +       if (!src)
  50 +               return false;
  51 +
  52 +       return ether_addr_equal(src, p->eth_addr);
  53 +}
  54 +
  55  static int br_multicast_add_group(struct net_bridge *br,
  56                                   struct net_bridge_port *port,
  57 -                                 struct br_ip *group)
  58 +                                 struct br_ip *group,
  59 +                                 const unsigned char *src)
  60  {
  61         struct net_bridge_mdb_entry *mp;
  62         struct net_bridge_port_group *p;
  63 @@ -682,13 +704,13 @@ static int br_multicast_add_group(struct
  64         for (pp = &mp->ports;
  65              (p = mlock_dereference(*pp, br)) != NULL;
  66              pp = &p->next) {
  67 -               if (p->port == port)
  68 +               if (br_port_group_equal(p, port, src))
  69                         goto found;
  70                 if ((unsigned long)p->port < (unsigned long)port)
  71                         break;
  72         }
  73
  74 -       p = br_multicast_new_port_group(port, group, *pp, MDB_TEMPORARY);
  75 +       p = br_multicast_new_port_group(port, group, *pp, MDB_TEMPORARY, src);
  76         if (unlikely(!p))
  77                 goto err;
  78         rcu_assign_pointer(*pp, p);
  79 @@ -707,7 +729,7 @@ err:
  80  static int br_ip4_multicast_add_group(struct net_bridge *br,
  81                                       struct net_bridge_port *port,
  82                                       __be32 group,
  83 -                                     __u16 vid)
  84 +                                     __u16 vid, const unsigned char *src)
  85  {
  86         struct br_ip br_group;
  87
  88 @@ -718,14 +740,14 @@ static int br_ip4_multicast_add_group(st
  89         br_group.proto = htons(ETH_P_IP);
  90         br_group.vid = vid;
  91
  92 -       return br_multicast_add_group(br, port, &br_group);
  93 +       return br_multicast_add_group(br, port, &br_group, src);
  94  }
  95
  96  #if IS_ENABLED(CONFIG_IPV6)
  97  static int br_ip6_multicast_add_group(struct net_bridge *br,
  98                                       struct net_bridge_port *port,
  99                                       const struct in6_addr *group,
 100 -                                     __u16 vid)
 101 +                                     __u16 vid, const unsigned char *src)
 102  {
 103         struct br_ip br_group;
 104
 105 @@ -736,7 +758,7 @@ static int br_ip6_multicast_add_group(st
 106         br_group.proto = htons(ETH_P_IPV6);
 107         br_group.vid = vid;
 108
 109 -       return br_multicast_add_group(br, port, &br_group);
 110 +       return br_multicast_add_group(br, port, &br_group, src);
 111  }
 112  #endif
 113
 114 @@ -966,6 +988,7 @@ static int br_ip4_multicast_igmp3_report
 115                                          struct sk_buff *skb,
 116                                          u16 vid)
 117  {
 118 +       const unsigned char *src;
 119         struct igmpv3_report *ih;
 120         struct igmpv3_grec *grec;
 121         int i;
 122 @@ -1009,7 +1032,8 @@ static int br_ip4_multicast_igmp3_report
 123                         continue;
 124                 }
 125
 126 -               err = br_ip4_multicast_add_group(br, port, group, vid);
 127 +               src = eth_hdr(skb)->h_source;
 128 +               err = br_ip4_multicast_add_group(br, port, group, vid, src);
 129                 if (err)
 130                         break;
 131         }
 132 @@ -1023,6 +1047,7 @@ static int br_ip6_multicast_mld2_report(
 133                                         struct sk_buff *skb,
 134                                         u16 vid)
 135  {
 136 +       const unsigned char *src = eth_hdr(skb)->h_source;
 137         struct icmp6hdr *icmp6h;
 138         struct mld2_grec *grec;
 139         int i;
 140 @@ -1071,7 +1096,7 @@ static int br_ip6_multicast_mld2_report(
 141                 }
 142
 143                 err = br_ip6_multicast_add_group(br, port, &grec->grec_mca,
 144 -                                                vid);
 145 +                                                vid, src);
 146                 if (err)
 147                         break;
 148         }
 149 @@ -1407,7 +1432,8 @@ br_multicast_leave_group(struct net_brid
 150                          struct net_bridge_port *port,
 151                          struct br_ip *group,
 152                          struct bridge_mcast_other_query *other_query,
 153 -                        struct bridge_mcast_own_query *own_query)
 154 +                        struct bridge_mcast_own_query *own_query,
 155 +                        const unsigned char *src)
 156  {
 157         struct net_bridge_mdb_htable *mdb;
 158         struct net_bridge_mdb_entry *mp;
 159 @@ -1457,7 +1483,7 @@ br_multicast_leave_group(struct net_brid
 160                 for (pp = &mp->ports;
 161                      (p = mlock_dereference(*pp, br)) != NULL;
 162                      pp = &p->next) {
 163 -                       if (p->port != port)
 164 +                       if (!br_port_group_equal(p, port, src))
 165                                 continue;
 166
 167                         rcu_assign_pointer(*pp, p->next);
 168 @@ -1491,7 +1517,7 @@ br_multicast_leave_group(struct net_brid
 169         for (p = mlock_dereference(mp->ports, br);
 170              p != NULL;
 171              p = mlock_dereference(p->next, br)) {
 172 -               if (p->port != port)
 173 +               if (!br_port_group_equal(p, port, src))
 174                         continue;
 175
 176                 if (!hlist_unhashed(&p->mglist) &&
 177 @@ -1509,8 +1535,8 @@ out:
 178
 179  static void br_ip4_multicast_leave_group(struct net_bridge *br,
 180                                          struct net_bridge_port *port,
 181 -                                        __be32 group,
 182 -                                        __u16 vid)
 183 +                                        __be32 group, __u16 vid,
 184 +                                        const unsigned char *src)
 185  {
 186         struct br_ip br_group;
 187         struct bridge_mcast_own_query *own_query;
 188 @@ -1525,14 +1551,14 @@ static void br_ip4_multicast_leave_group
 189         br_group.vid = vid;
 190
 191         br_multicast_leave_group(br, port, &br_group, &br->ip4_other_query,
 192 -                                own_query);
 193 +                                own_query, src);
 194  }
 195
 196  #if IS_ENABLED(CONFIG_IPV6)
 197  static void br_ip6_multicast_leave_group(struct net_bridge *br,
 198                                          struct net_bridge_port *port,
 199                                          const struct in6_addr *group,
 200 -                                        __u16 vid)
 201 +                                        __u16 vid, const unsigned char *src)
 202  {
 203         struct br_ip br_group;
 204         struct bridge_mcast_own_query *own_query;
 205 @@ -1547,7 +1573,7 @@ static void br_ip6_multicast_leave_group
 206         br_group.vid = vid;
 207
 208         br_multicast_leave_group(br, port, &br_group, &br->ip6_other_query,
 209 -                                own_query);
 210 +                                own_query, src);
 211  }
 212  #endif
 213
 214 @@ -1556,6 +1582,7 @@ static int br_multicast_ipv4_rcv(struct
 215                                  struct sk_buff *skb,
 216                                  u16 vid)
 217  {
 218 +       const unsigned char *src;
 219         struct sk_buff *skb2 = skb;
 220         const struct iphdr *iph;
 221         struct igmphdr *ih;
 222 @@ -1624,12 +1651,13 @@ static int br_multicast_ipv4_rcv(struct
 223
 224         BR_INPUT_SKB_CB(skb)->igmp = 1;
 225         ih = igmp_hdr(skb2);
 226 +       src = eth_hdr(skb)->h_source;
 227
 228         switch (ih->type) {
 229         case IGMP_HOST_MEMBERSHIP_REPORT:
 230         case IGMPV2_HOST_MEMBERSHIP_REPORT:
 231                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
 232 -               err = br_ip4_multicast_add_group(br, port, ih->group, vid);
 233 +               err = br_ip4_multicast_add_group(br, port, ih->group, vid, src);
 234                 break;
 235         case IGMPV3_HOST_MEMBERSHIP_REPORT:
 236                 err = br_ip4_multicast_igmp3_report(br, port, skb2, vid);
 237 @@ -1638,7 +1666,7 @@ static int br_multicast_ipv4_rcv(struct
 238                 err = br_ip4_multicast_query(br, port, skb2, vid);
 239                 break;
 240         case IGMP_HOST_LEAVE_MESSAGE:
 241 -               br_ip4_multicast_leave_group(br, port, ih->group, vid);
 242 +               br_ip4_multicast_leave_group(br, port, ih->group, vid, src);
 243                 break;
 244         }
 245
 246 @@ -1656,6 +1684,7 @@ static int br_multicast_ipv6_rcv(struct
 247                                  struct sk_buff *skb,
 248                                  u16 vid)
 249  {
 250 +       const unsigned char *src;
 251         struct sk_buff *skb2;
 252         const struct ipv6hdr *ip6h;
 253         u8 icmp6_type;
 254 @@ -1763,9 +1792,11 @@ static int br_multicast_ipv6_rcv(struct
 255                         err = -EINVAL;
 256                         goto out;
 257                 }
 258 +               src = eth_hdr(skb)->h_source;
 259                 mld = (struct mld_msg *)skb_transport_header(skb2);
 260                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
 261 -               err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid);
 262 +               err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid,
 263 +                                                src);
 264                 break;
 265             }
 266         case ICMPV6_MLD2_REPORT:
 267 @@ -1781,8 +1812,9 @@ static int br_multicast_ipv6_rcv(struct
 268                         err = -EINVAL;
 269                         goto out;
 270                 }
 271 +               src = eth_hdr(skb)->h_source;
 272                 mld = (struct mld_msg *)skb_transport_header(skb2);
 273 -               br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid);
 274 +               br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid, src);
 275             }
 276         }
 277
 278 --- a/net/bridge/br_private.h
 279 +++ b/net/bridge/br_private.h
 280 @@ -113,6 +113,9 @@ struct net_bridge_port_group {
 281         struct timer_list               timer;
 282         struct br_ip                    addr;
 283         unsigned char                   state;
 284 +
 285 +       unsigned char                   eth_addr[ETH_ALEN];
 286 +       bool                            unicast;
 287  };
 288
 289  struct net_bridge_mdb_entry
 290 @@ -481,7 +484,8 @@ void br_multicast_free_pg(struct rcu_hea
 291  struct net_bridge_port_group *
 292  br_multicast_new_port_group(struct net_bridge_port *port, struct br_ip *group,
 293                             struct net_bridge_port_group __rcu *next,
 294 -                           unsigned char state);
 295 +                           unsigned char state,
 296 +                      const unsigned char *src);
 297  void br_mdb_init(void);
 298  void br_mdb_uninit(void);
 299  void br_mdb_notify(struct net_device *dev, struct net_bridge_port *port,
 300 --- a/net/bridge/br_mdb.c
 301 +++ b/net/bridge/br_mdb.c
 302 @@ -343,7 +343,7 @@ static int br_mdb_add_group(struct net_b
 303                         break;
 304         }
 305
 306 -       p = br_multicast_new_port_group(port, group, *pp, state);
 307 +       p = br_multicast_new_port_group(port, group, *pp, state, NULL);
 308         if (unlikely(!p))
 309                 return -ENOMEM;
 310         rcu_assign_pointer(*pp, p);
 311 --- a/net/bridge/br_forward.c
 312 +++ b/net/bridge/br_forward.c
 313 @@ -170,6 +170,34 @@ out:
 314         return p;
 315  }
 316
 317 +static struct net_bridge_port *maybe_deliver_addr(
 318 +       struct net_bridge_port *prev, struct net_bridge_port *p,
 319 +       struct sk_buff *skb, const unsigned char *addr,
 320 +       void (*__packet_hook)(const struct net_bridge_port *p,
 321 +                             struct sk_buff *skb))
 322 +{
 323 +       struct net_device *dev = BR_INPUT_SKB_CB(skb)->brdev;
 324 +       const unsigned char *src = eth_hdr(skb)->h_source;
 325 +
 326 +       if (!should_deliver(p, skb))
 327 +               return prev;
 328 +
 329 +       /* Even with hairpin, no soliloquies - prevent breaking IPv6 DAD */
 330 +       if (skb->dev == p->dev && ether_addr_equal(src, addr))
 331 +               return prev;
 332 +
 333 +       skb = skb_copy(skb, GFP_ATOMIC);
 334 +       if (!skb) {
 335 +               dev->stats.tx_dropped++;
 336 +               return prev;
 337 +       }
 338 +
 339 +       memcpy(eth_hdr(skb)->h_dest, addr, ETH_ALEN);
 340 +       __packet_hook(p, skb);
 341 +
 342 +       return prev;
 343 +}
 344 +
 345  /* called under bridge lock */
 346  static void br_flood(struct net_bridge *br, struct sk_buff *skb,
 347                      struct sk_buff *skb0,
 348 @@ -242,6 +270,7 @@ static void br_multicast_flood(struct ne
 349         struct net_bridge_port *prev = NULL;
 350         struct net_bridge_port_group *p;
 351         struct hlist_node *rp;
 352 +       const unsigned char *addr;
 353
 354         rp = rcu_dereference(hlist_first_rcu(&br->router_list));
 355         p = mdst ? rcu_dereference(mdst->ports) : NULL;
 356 @@ -252,10 +281,19 @@ static void br_multicast_flood(struct ne
 357                 rport = rp ? hlist_entry(rp, struct net_bridge_port, rlist) :
 358                              NULL;
 359
 360 -               port = (unsigned long)lport > (unsigned long)rport ?
 361 -                      lport : rport;
 362 -
 363 -               prev = maybe_deliver(prev, port, skb, __packet_hook);
 364 +               if ((unsigned long)lport > (unsigned long)rport) {
 365 +                       port = lport;
 366 +                       addr = p->unicast ? p->eth_addr : NULL;
 367 +               } else {
 368 +                       port = rport;
 369 +                       addr = NULL;
 370 +               }
 371 +
 372 +               if (addr)
 373 +                       prev = maybe_deliver_addr(prev, port, skb, addr,
 374 +                                                 __packet_hook);
 375 +               else
 376 +                       prev = maybe_deliver(prev, port, skb, __packet_hook);
 377                 if (IS_ERR(prev))
 378                         goto out;
 379
 380 --- a/net/bridge/br_sysfs_if.c
 381 +++ b/net/bridge/br_sysfs_if.c
 382 @@ -204,6 +204,7 @@ static BRPORT_ATTR(multicast_router, S_I
 383                    store_multicast_router);
 384
 385  BRPORT_ATTR_FLAG(multicast_fast_leave, BR_MULTICAST_FAST_LEAVE);
 386 +BRPORT_ATTR_FLAG(multicast_to_unicast, BR_MULTICAST_TO_UCAST);
 387  #endif
 388
 389  static const struct brport_attribute *brport_attrs[] = {
 390 @@ -230,6 +231,7 @@ static const struct brport_attribute *br
 391  #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
 392         &brport_attr_multicast_router,
 393         &brport_attr_multicast_fast_leave,
 394 +       &brport_attr_multicast_to_unicast,
 395  #endif
 396         &brport_attr_proxyarp,
 397         &brport_attr_proxyarp_wifi,