forked from mirrors/linux
bridge: suppress arp pkts on BR_NEIGH_SUPPRESS ports
This patch avoids flooding and proxies arp packets for BR_NEIGH_SUPPRESS ports. Moves existing br_do_proxy_arp to br_do_proxy_suppress_arp to support both proxy arp and neigh suppress. Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Roopa Prabhu
David S. Miller
parent
821f1b21ca
commit
057658cb33
4 changed files with 205 additions and 58 deletions
|
|
@ -14,6 +14,14 @@
|
|||
*/
|
||||
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/netdevice.h>
|
||||
#include <linux/etherdevice.h>
|
||||
#include <linux/neighbour.h>
|
||||
#include <net/arp.h>
|
||||
#include <linux/if_vlan.h>
|
||||
#include <linux/inetdevice.h>
|
||||
#include <net/addrconf.h>
|
||||
|
||||
#include "br_private.h"
|
||||
|
||||
void br_recalculate_neigh_suppress_enabled(struct net_bridge *br)
|
||||
|
|
@ -30,3 +38,183 @@ void br_recalculate_neigh_suppress_enabled(struct net_bridge *br)
|
|||
|
||||
br->neigh_suppress_enabled = neigh_suppress;
|
||||
}
|
||||
|
||||
#if IS_ENABLED(CONFIG_INET)
|
||||
static void br_arp_send(struct net_bridge *br, struct net_bridge_port *p,
|
||||
struct net_device *dev, __be32 dest_ip, __be32 src_ip,
|
||||
const unsigned char *dest_hw,
|
||||
const unsigned char *src_hw,
|
||||
const unsigned char *target_hw,
|
||||
__be16 vlan_proto, u16 vlan_tci)
|
||||
{
|
||||
struct net_bridge_vlan_group *vg;
|
||||
struct sk_buff *skb;
|
||||
u16 pvid;
|
||||
|
||||
netdev_dbg(dev, "arp send dev %s dst %pI4 dst_hw %pM src %pI4 src_hw %pM\n",
|
||||
dev->name, &dest_ip, dest_hw, &src_ip, src_hw);
|
||||
|
||||
if (!vlan_tci) {
|
||||
arp_send(ARPOP_REPLY, ETH_P_ARP, dest_ip, dev, src_ip,
|
||||
dest_hw, src_hw, target_hw);
|
||||
return;
|
||||
}
|
||||
|
||||
skb = arp_create(ARPOP_REPLY, ETH_P_ARP, dest_ip, dev, src_ip,
|
||||
dest_hw, src_hw, target_hw);
|
||||
if (!skb)
|
||||
return;
|
||||
|
||||
if (p)
|
||||
vg = nbp_vlan_group_rcu(p);
|
||||
else
|
||||
vg = br_vlan_group_rcu(br);
|
||||
pvid = br_get_pvid(vg);
|
||||
if (pvid == (vlan_tci & VLAN_VID_MASK))
|
||||
vlan_tci = 0;
|
||||
|
||||
if (vlan_tci)
|
||||
__vlan_hwaccel_put_tag(skb, vlan_proto, vlan_tci);
|
||||
|
||||
if (p) {
|
||||
arp_xmit(skb);
|
||||
} else {
|
||||
skb_reset_mac_header(skb);
|
||||
__skb_pull(skb, skb_network_offset(skb));
|
||||
skb->ip_summed = CHECKSUM_UNNECESSARY;
|
||||
skb->pkt_type = PACKET_HOST;
|
||||
|
||||
netif_rx_ni(skb);
|
||||
}
|
||||
}
|
||||
|
||||
static int br_chk_addr_ip(struct net_device *dev, void *data)
|
||||
{
|
||||
__be32 ip = *(__be32 *)data;
|
||||
struct in_device *in_dev;
|
||||
__be32 addr = 0;
|
||||
|
||||
in_dev = __in_dev_get_rcu(dev);
|
||||
if (in_dev)
|
||||
addr = inet_confirm_addr(dev_net(dev), in_dev, 0, ip,
|
||||
RT_SCOPE_HOST);
|
||||
|
||||
if (addr == ip)
|
||||
return 1;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static bool br_is_local_ip(struct net_device *dev, __be32 ip)
|
||||
{
|
||||
if (br_chk_addr_ip(dev, &ip))
|
||||
return true;
|
||||
|
||||
/* check if ip is configured on upper dev */
|
||||
if (netdev_walk_all_upper_dev_rcu(dev, br_chk_addr_ip, &ip))
|
||||
return true;
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
void br_do_proxy_suppress_arp(struct sk_buff *skb, struct net_bridge *br,
|
||||
u16 vid, struct net_bridge_port *p)
|
||||
{
|
||||
struct net_device *dev = br->dev;
|
||||
struct net_device *vlandev = dev;
|
||||
struct neighbour *n;
|
||||
struct arphdr *parp;
|
||||
u8 *arpptr, *sha;
|
||||
__be32 sip, tip;
|
||||
|
||||
BR_INPUT_SKB_CB(skb)->proxyarp_replied = false;
|
||||
|
||||
if ((dev->flags & IFF_NOARP) ||
|
||||
!pskb_may_pull(skb, arp_hdr_len(dev)))
|
||||
return;
|
||||
|
||||
parp = arp_hdr(skb);
|
||||
|
||||
if (parp->ar_pro != htons(ETH_P_IP) ||
|
||||
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;
|
||||
|
||||
if (br->neigh_suppress_enabled) {
|
||||
if (p && (p->flags & BR_NEIGH_SUPPRESS))
|
||||
return;
|
||||
if (ipv4_is_zeronet(sip) || sip == tip) {
|
||||
/* prevent flooding to neigh suppress ports */
|
||||
BR_INPUT_SKB_CB(skb)->proxyarp_replied = true;
|
||||
return;
|
||||
}
|
||||
}
|
||||
|
||||
if (parp->ar_op != htons(ARPOP_REQUEST))
|
||||
return;
|
||||
|
||||
if (vid != 0) {
|
||||
vlandev = __vlan_find_dev_deep_rcu(br->dev, skb->vlan_proto,
|
||||
vid);
|
||||
if (!vlandev)
|
||||
return;
|
||||
}
|
||||
|
||||
if (br->neigh_suppress_enabled && br_is_local_ip(vlandev, tip)) {
|
||||
/* its our local ip, so don't proxy reply
|
||||
* and don't forward to neigh suppress ports
|
||||
*/
|
||||
BR_INPUT_SKB_CB(skb)->proxyarp_replied = true;
|
||||
return;
|
||||
}
|
||||
|
||||
n = neigh_lookup(&arp_tbl, &tip, vlandev);
|
||||
if (n) {
|
||||
struct net_bridge_fdb_entry *f;
|
||||
|
||||
if (!(n->nud_state & NUD_VALID)) {
|
||||
neigh_release(n);
|
||||
return;
|
||||
}
|
||||
|
||||
f = br_fdb_find_rcu(br, n->ha, vid);
|
||||
if (f) {
|
||||
bool replied = false;
|
||||
|
||||
if ((p && (p->flags & BR_PROXYARP)) ||
|
||||
(f->dst && (f->dst->flags & (BR_PROXYARP_WIFI |
|
||||
BR_NEIGH_SUPPRESS)))) {
|
||||
if (!vid)
|
||||
br_arp_send(br, p, skb->dev, sip, tip,
|
||||
sha, n->ha, sha, 0, 0);
|
||||
else
|
||||
br_arp_send(br, p, skb->dev, sip, tip,
|
||||
sha, n->ha, sha,
|
||||
skb->vlan_proto,
|
||||
skb_vlan_tag_get(skb));
|
||||
replied = true;
|
||||
}
|
||||
|
||||
/* If we have replied or as long as we know the
|
||||
* mac, indicate to arp replied
|
||||
*/
|
||||
if (replied || br->neigh_suppress_enabled)
|
||||
BR_INPUT_SKB_CB(skb)->proxyarp_replied = true;
|
||||
}
|
||||
|
||||
neigh_release(n);
|
||||
}
|
||||
}
|
||||
#endif
|
||||
|
|
|
|||
|
|
@ -39,6 +39,7 @@ netdev_tx_t br_dev_xmit(struct sk_buff *skb, struct net_device *dev)
|
|||
struct pcpu_sw_netstats *brstats = this_cpu_ptr(br->stats);
|
||||
const struct nf_br_ops *nf_ops;
|
||||
const unsigned char *dest;
|
||||
struct ethhdr *eth;
|
||||
u16 vid = 0;
|
||||
|
||||
rcu_read_lock();
|
||||
|
|
@ -57,11 +58,19 @@ netdev_tx_t br_dev_xmit(struct sk_buff *skb, struct net_device *dev)
|
|||
BR_INPUT_SKB_CB(skb)->brdev = dev;
|
||||
|
||||
skb_reset_mac_header(skb);
|
||||
eth = eth_hdr(skb);
|
||||
skb_pull(skb, ETH_HLEN);
|
||||
|
||||
if (!br_allowed_ingress(br, br_vlan_group_rcu(br), skb, &vid))
|
||||
goto out;
|
||||
|
||||
if (IS_ENABLED(CONFIG_INET) &&
|
||||
(eth->h_proto == htons(ETH_P_ARP) ||
|
||||
eth->h_proto == htons(ETH_P_RARP)) &&
|
||||
br->neigh_suppress_enabled) {
|
||||
br_do_proxy_suppress_arp(skb, br, vid, NULL);
|
||||
}
|
||||
|
||||
dest = eth_hdr(skb)->h_dest;
|
||||
if (is_broadcast_ether_addr(dest)) {
|
||||
br_flood(br, skb, BR_PKT_BROADCAST, false, true);
|
||||
|
|
|
|||
|
|
@ -71,62 +71,6 @@ static int br_pass_frame_up(struct sk_buff *skb)
|
|||
br_netif_receive_skb);
|
||||
}
|
||||
|
||||
static void br_do_proxy_arp(struct sk_buff *skb, struct net_bridge *br,
|
||||
u16 vid, struct net_bridge_port *p)
|
||||
{
|
||||
struct net_device *dev = br->dev;
|
||||
struct neighbour *n;
|
||||
struct arphdr *parp;
|
||||
u8 *arpptr, *sha;
|
||||
__be32 sip, tip;
|
||||
|
||||
BR_INPUT_SKB_CB(skb)->proxyarp_replied = false;
|
||||
|
||||
if ((dev->flags & IFF_NOARP) ||
|
||||
!pskb_may_pull(skb, arp_hdr_len(dev)))
|
||||
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_find_rcu(br, n->ha, vid);
|
||||
if (f && ((p->flags & BR_PROXYARP) ||
|
||||
(f->dst && (f->dst->flags & BR_PROXYARP_WIFI)))) {
|
||||
arp_send(ARPOP_REPLY, ETH_P_ARP, sip, skb->dev, tip,
|
||||
sha, n->ha, sha);
|
||||
BR_INPUT_SKB_CB(skb)->proxyarp_replied = true;
|
||||
}
|
||||
|
||||
neigh_release(n);
|
||||
}
|
||||
}
|
||||
|
||||
/* note: already called with rcu_read_lock */
|
||||
int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
|
||||
{
|
||||
|
|
@ -171,8 +115,11 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb
|
|||
|
||||
BR_INPUT_SKB_CB(skb)->brdev = br->dev;
|
||||
|
||||
if (IS_ENABLED(CONFIG_INET) && skb->protocol == htons(ETH_P_ARP))
|
||||
br_do_proxy_arp(skb, br, vid, p);
|
||||
if (IS_ENABLED(CONFIG_INET) &&
|
||||
(skb->protocol == htons(ETH_P_ARP) ||
|
||||
skb->protocol == htons(ETH_P_RARP))) {
|
||||
br_do_proxy_suppress_arp(skb, br, vid, p);
|
||||
}
|
||||
|
||||
switch (pkt_type) {
|
||||
case BR_PKT_MULTICAST:
|
||||
|
|
|
|||
|
|
@ -1140,5 +1140,8 @@ static inline void br_switchdev_frame_unmark(struct sk_buff *skb)
|
|||
}
|
||||
#endif /* CONFIG_NET_SWITCHDEV */
|
||||
|
||||
/* br_arp_nd_proxy.c */
|
||||
void br_recalculate_neigh_suppress_enabled(struct net_bridge *br);
|
||||
void br_do_proxy_suppress_arp(struct sk_buff *skb, struct net_bridge *br,
|
||||
u16 vid, struct net_bridge_port *p);
|
||||
#endif
|
||||
|
|
|
|||
Loading…
Reference in a new issue