diff options
Diffstat (limited to 'net/bridge/br_input.c')
| -rw-r--r-- | net/bridge/br_input.c | 138 |
1 files changed, 94 insertions, 44 deletions
diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c index 88e4aa9cb1f..366c4364907 100644 --- a/net/bridge/br_input.c +++ b/net/bridge/br_input.c @@ -16,11 +16,10 @@ #include <linux/netdevice.h> #include <linux/etherdevice.h> #include <linux/netfilter_bridge.h> +#include <linux/export.h> +#include <linux/rculist.h> #include "br_private.h" -/* Bridge group multicast address 802.1d (pg 51). */ -const u8 br_group_address[ETH_ALEN] = { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 }; - /* Hook for brouter */ br_should_route_hook_t __rcu *br_should_route_hook __read_mostly; EXPORT_SYMBOL(br_should_route_hook); @@ -29,15 +28,30 @@ static int br_pass_frame_up(struct sk_buff *skb) { struct net_device *indev, *brdev = BR_INPUT_SKB_CB(skb)->brdev; struct net_bridge *br = netdev_priv(brdev); - struct br_cpu_netstats *brstats = this_cpu_ptr(br->stats); + struct pcpu_sw_netstats *brstats = this_cpu_ptr(br->stats); + struct net_port_vlans *pv; u64_stats_update_begin(&brstats->syncp); brstats->rx_packets++; brstats->rx_bytes += skb->len; u64_stats_update_end(&brstats->syncp); + /* Bridge is just like any other port. Make sure the + * packet is allowed except in promisc modue when someone + * may be running packet capture. + */ + pv = br_get_vlan_info(br); + if (!(brdev->flags & IFF_PROMISC) && + !br_allowed_egress(br, pv, skb)) { + kfree_skb(skb); + return NET_RX_DROP; + } + indev = skb->dev; skb->dev = brdev; + skb = br_handle_vlan(br, pv, skb); + if (!skb) + return NET_RX_DROP; return NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_IN, skb, indev, NULL, netif_receive_skb); @@ -52,16 +66,22 @@ int br_handle_frame_finish(struct sk_buff *skb) struct net_bridge_fdb_entry *dst; struct net_bridge_mdb_entry *mdst; struct sk_buff *skb2; + bool unicast = true; + u16 vid = 0; if (!p || p->state == BR_STATE_DISABLED) goto drop; + if (!br_allowed_ingress(p->br, nbp_get_vlan_info(p), skb, &vid)) + goto out; + /* insert into forwarding database after filtering to avoid spoofing */ br = p->br; - br_fdb_update(br, p, eth_hdr(skb)->h_source); + if (p->flags & BR_LEARNING) + br_fdb_update(br, p, eth_hdr(skb)->h_source, vid, false); - if (is_multicast_ether_addr(dest) && - br_multicast_rcv(br, p, skb)) + if (!is_broadcast_ether_addr(dest) && is_multicast_ether_addr(dest) && + br_multicast_rcv(br, p, skb, vid)) goto drop; if (p->state == BR_STATE_LEARNING) @@ -77,9 +97,13 @@ int br_handle_frame_finish(struct sk_buff *skb) dst = NULL; - if (is_multicast_ether_addr(dest)) { - mdst = br_mdb_get(br, skb); - if (mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) { + if (is_broadcast_ether_addr(dest)) { + skb2 = skb; + unicast = false; + } else if (is_multicast_ether_addr(dest)) { + mdst = br_mdb_get(br, skb, vid); + if ((mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) && + br_multicast_querier_exists(br, eth_hdr(skb))) { if ((mdst && mdst->mglist) || br_multicast_is_router(br)) skb2 = skb; @@ -90,18 +114,21 @@ int br_handle_frame_finish(struct sk_buff *skb) } else skb2 = skb; + unicast = false; br->dev->stats.multicast++; - } else if ((dst = __br_fdb_get(br, dest)) && dst->is_local) { + } else if ((dst = __br_fdb_get(br, dest, vid)) && + dst->is_local) { skb2 = skb; /* Do not forward the packet since it's local. */ skb = NULL; } if (skb) { - if (dst) + if (dst) { + dst->used = jiffies; br_forward(dst->dst, skb, skb2); - else - br_flood_forward(br, skb, skb2); + } else + br_flood_forward(br, skb, skb2, unicast); } if (skb2) @@ -118,59 +145,80 @@ drop: static int br_handle_local_finish(struct sk_buff *skb) { struct net_bridge_port *p = br_port_get_rcu(skb->dev); + u16 vid = 0; - br_fdb_update(p->br, p, eth_hdr(skb)->h_source); + /* check if vlan is allowed, to avoid spoofing */ + if (p->flags & BR_LEARNING && br_should_learn(p, skb, &vid)) + br_fdb_update(p->br, p, eth_hdr(skb)->h_source, vid, false); return 0; /* process further */ } -/* Does address match the link local multicast address. - * 01:80:c2:00:00:0X - */ -static inline int is_link_local(const unsigned char *dest) -{ - __be16 *a = (__be16 *)dest; - static const __be16 *b = (const __be16 *)br_group_address; - static const __be16 m = cpu_to_be16(0xfff0); - - return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | ((a[2] ^ b[2]) & m)) == 0; -} - /* * Return NULL if skb is handled * note: already called with rcu_read_lock */ -struct sk_buff *br_handle_frame(struct sk_buff *skb) +rx_handler_result_t br_handle_frame(struct sk_buff **pskb) { struct net_bridge_port *p; + struct sk_buff *skb = *pskb; const unsigned char *dest = eth_hdr(skb)->h_dest; br_should_route_hook_t *rhook; if (unlikely(skb->pkt_type == PACKET_LOOPBACK)) - return skb; + return RX_HANDLER_PASS; if (!is_valid_ether_addr(eth_hdr(skb)->h_source)) goto drop; skb = skb_share_check(skb, GFP_ATOMIC); if (!skb) - return NULL; + return RX_HANDLER_CONSUMED; p = br_port_get_rcu(skb->dev); - if (unlikely(is_link_local(dest))) { - /* Pause frames shouldn't be passed up by driver anyway */ - if (skb->protocol == htons(ETH_P_PAUSE)) + if (unlikely(is_link_local_ether_addr(dest))) { + u16 fwd_mask = p->br->group_fwd_mask_required; + + /* + * See IEEE 802.1D Table 7-10 Reserved addresses + * + * Assignment Value + * Bridge Group Address 01-80-C2-00-00-00 + * (MAC Control) 802.3 01-80-C2-00-00-01 + * (Link Aggregation) 802.3 01-80-C2-00-00-02 + * 802.1X PAE address 01-80-C2-00-00-03 + * + * 802.1AB LLDP 01-80-C2-00-00-0E + * + * Others reserved for future standardization + */ + switch (dest[5]) { + case 0x00: /* Bridge Group Address */ + /* If STP is turned off, + then must forward to keep loop detection */ + if (p->br->stp_enabled == BR_NO_STP || + fwd_mask & (1u << dest[5])) + goto forward; + break; + + case 0x01: /* IEEE MAC (Pause) */ goto drop; - /* If STP is turned off, then forward */ - if (p->br->stp_enabled == BR_NO_STP) - goto forward; + default: + /* Allow selective forwarding for most other protocols */ + fwd_mask |= p->br->group_fwd_mask; + if (fwd_mask & (1u << dest[5])) + goto forward; + } + /* Deliver packet to local host only */ if (NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_IN, skb, skb->dev, - NULL, br_handle_local_finish)) - return NULL; /* frame consumed by filter */ - else - return skb; /* continue processing */ + NULL, br_handle_local_finish)) { + return RX_HANDLER_CONSUMED; /* consumed by filter */ + } else { + *pskb = skb; + return RX_HANDLER_PASS; /* continue processing */ + } } forward: @@ -178,13 +226,15 @@ forward: case BR_STATE_FORWARDING: rhook = rcu_dereference(br_should_route_hook); if (rhook) { - if ((*rhook)(skb)) - return skb; + if ((*rhook)(skb)) { + *pskb = skb; + return RX_HANDLER_PASS; + } dest = eth_hdr(skb)->h_dest; } /* fall through */ case BR_STATE_LEARNING: - if (!compare_ether_addr(p->br->dev->dev_addr, dest)) + if (ether_addr_equal(p->br->dev->dev_addr, dest)) skb->pkt_type = PACKET_HOST; NF_HOOK(NFPROTO_BRIDGE, NF_BR_PRE_ROUTING, skb, skb->dev, NULL, @@ -194,5 +244,5 @@ forward: drop: kfree_skb(skb); } - return NULL; + return RX_HANDLER_CONSUMED; } |
