diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h index 0bdb77e16875..7072d8325016 100644 --- a/include/uapi/linux/if_link.h +++ b/include/uapi/linux/if_link.h @@ -243,6 +243,7 @@ enum { IFLA_BRPORT_FAST_LEAVE, /* multicast fast leave */ IFLA_BRPORT_LEARNING, /* mac learning */ IFLA_BRPORT_UNICAST_FLOOD, /* flood unicast traffic */ + IFLA_BRPORT_PROXYARP, /* proxy ARP */ __IFLA_BRPORT_MAX }; #define IFLA_BRPORT_MAX (__IFLA_BRPORT_MAX - 1) diff --git a/net/bridge/br_forward.c b/net/bridge/br_forward.c index 992ec49a96aa..1510b54e6a2e 100644 --- a/net/bridge/br_forward.c +++ b/net/bridge/br_forward.c @@ -183,6 +183,11 @@ static void br_flood(struct net_bridge *br, struct sk_buff *skb, /* Do not flood unicast traffic to ports that turn it off */ if (unicast && !(p->flags & BR_FLOOD)) continue; + + /* Do not flood to ports that enable proxy ARP */ + if (p->flags & BR_PROXYARP) + continue; + prev = maybe_deliver(prev, p, skb, __packet_hook); if (IS_ERR(prev)) goto out; diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c index 6fd5522df696..1f1de715197c 100644 --- a/net/bridge/br_input.c +++ b/net/bridge/br_input.c @@ -16,6 +16,8 @@ #include #include #include +#include +#include #include #include #include "br_private.h" @@ -57,6 +59,60 @@ static int br_pass_frame_up(struct sk_buff *skb) netif_receive_skb); } +static void br_do_proxy_arp(struct sk_buff *skb, struct net_bridge *br, + u16 vid) +{ + struct net_device *dev = br->dev; + struct neighbour *n; + struct arphdr *parp; + u8 *arpptr, *sha; + __be32 sip, tip; + + if (dev->flags & IFF_NOARP) + return; + + if (!pskb_may_pull(skb, arp_hdr_len(dev))) { + dev->stats.tx_dropped++; + return; + } + parp = arp_hdr(skb); + + if (parp->ar_pro != htons(ETH_P_IP) || + parp->ar_op != htons(ARPOP_REQUEST) || + parp->ar_hln != dev->addr_len || + parp->ar_pln != 4) + return; + + arpptr = (u8 *)parp + sizeof(struct arphdr); + sha = arpptr; + arpptr += dev->addr_len; /* sha */ + memcpy(&sip, arpptr, sizeof(sip)); + arpptr += sizeof(sip); + arpptr += dev->addr_len; /* tha */ + memcpy(&tip, arpptr, sizeof(tip)); + + if (ipv4_is_loopback(tip) || + ipv4_is_multicast(tip)) + return; + + n = neigh_lookup(&arp_tbl, &tip, dev); + if (n) { + struct net_bridge_fdb_entry *f; + + if (!(n->nud_state & NUD_VALID)) { + neigh_release(n); + return; + } + + f = __br_fdb_get(br, n->ha, vid); + if (f) + arp_send(ARPOP_REPLY, ETH_P_ARP, sip, skb->dev, tip, + sha, n->ha, sha); + + neigh_release(n); + } +} + /* note: already called with rcu_read_lock */ int br_handle_frame_finish(struct sk_buff *skb) { @@ -98,6 +154,10 @@ int br_handle_frame_finish(struct sk_buff *skb) dst = NULL; if (is_broadcast_ether_addr(dest)) { + if (p->flags & BR_PROXYARP && + skb->protocol == htons(ETH_P_ARP)) + br_do_proxy_arp(skb, br, vid); + skb2 = skb; unicast = false; } else if (is_multicast_ether_addr(dest)) { diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c index 2ff9706647f2..86c239b06f6e 100644 --- a/net/bridge/br_netlink.c +++ b/net/bridge/br_netlink.c @@ -60,7 +60,8 @@ static int br_port_fill_attrs(struct sk_buff *skb, nla_put_u8(skb, IFLA_BRPORT_PROTECT, !!(p->flags & BR_ROOT_BLOCK)) || nla_put_u8(skb, IFLA_BRPORT_FAST_LEAVE, !!(p->flags & BR_MULTICAST_FAST_LEAVE)) || nla_put_u8(skb, IFLA_BRPORT_LEARNING, !!(p->flags & BR_LEARNING)) || - nla_put_u8(skb, IFLA_BRPORT_UNICAST_FLOOD, !!(p->flags & BR_FLOOD))) + nla_put_u8(skb, IFLA_BRPORT_UNICAST_FLOOD, !!(p->flags & BR_FLOOD)) || + nla_put_u8(skb, IFLA_BRPORT_PROXYARP, !!(p->flags & BR_PROXYARP))) return -EMSGSIZE; return 0; @@ -332,6 +333,7 @@ static int br_setport(struct net_bridge_port *p, struct nlattr *tb[]) br_set_port_flag(p, tb, IFLA_BRPORT_PROTECT, BR_ROOT_BLOCK); br_set_port_flag(p, tb, IFLA_BRPORT_LEARNING, BR_LEARNING); br_set_port_flag(p, tb, IFLA_BRPORT_UNICAST_FLOOD, BR_FLOOD); + br_set_port_flag(p, tb, IFLA_BRPORT_PROXYARP, BR_PROXYARP); if (tb[IFLA_BRPORT_COST]) { err = br_stp_set_path_cost(p, nla_get_u32(tb[IFLA_BRPORT_COST])); diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index 4d783d071305..8f3f08140258 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -172,6 +172,7 @@ struct net_bridge_port #define BR_FLOOD 0x00000040 #define BR_AUTO_MASK (BR_FLOOD | BR_LEARNING) #define BR_PROMISC 0x00000080 +#define BR_PROXYARP 0x00000100 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING struct bridge_mcast_own_query ip4_own_query; diff --git a/net/bridge/br_sysfs_if.c b/net/bridge/br_sysfs_if.c index e561cd59b8a6..2de5d91199e8 100644 --- a/net/bridge/br_sysfs_if.c +++ b/net/bridge/br_sysfs_if.c @@ -170,6 +170,7 @@ BRPORT_ATTR_FLAG(bpdu_guard, BR_BPDU_GUARD); BRPORT_ATTR_FLAG(root_block, BR_ROOT_BLOCK); BRPORT_ATTR_FLAG(learning, BR_LEARNING); BRPORT_ATTR_FLAG(unicast_flood, BR_FLOOD); +BRPORT_ATTR_FLAG(proxyarp, BR_PROXYARP); #ifdef CONFIG_BRIDGE_IGMP_SNOOPING static ssize_t show_multicast_router(struct net_bridge_port *p, char *buf) @@ -213,6 +214,7 @@ static const struct brport_attribute *brport_attrs[] = { &brport_attr_multicast_router, &brport_attr_multicast_fast_leave, #endif + &brport_attr_proxyarp, NULL };