forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
485 lines
11 KiB
485 lines
11 KiB
// SPDX-License-Identifier: GPL-2.0-or-later |
|
/* |
|
* Handle bridge arp/nd proxy/suppress |
|
* |
|
* Copyright (C) 2017 Cumulus Networks |
|
* Copyright (c) 2017 Roopa Prabhu <[email protected]> |
|
* |
|
* Authors: |
|
* Roopa Prabhu <[email protected]> |
|
*/ |
|
|
|
#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 <net/ipv6_stubs.h> |
|
#if IS_ENABLED(CONFIG_IPV6) |
|
#include <net/ip6_checksum.h> |
|
#endif |
|
|
|
#include "br_private.h" |
|
|
|
void br_recalculate_neigh_suppress_enabled(struct net_bridge *br) |
|
{ |
|
struct net_bridge_port *p; |
|
bool neigh_suppress = false; |
|
|
|
list_for_each_entry(p, &br->port_list, list) { |
|
if (p->flags & BR_NEIGH_SUPPRESS) { |
|
neigh_suppress = true; |
|
break; |
|
} |
|
} |
|
|
|
br_opt_toggle(br, BROPT_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, |
|
struct netdev_nested_priv *priv) |
|
{ |
|
__be32 ip = *(__be32 *)priv->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) |
|
{ |
|
struct netdev_nested_priv priv = { |
|
.data = (void *)&ip, |
|
}; |
|
|
|
if (br_chk_addr_ip(dev, &priv)) |
|
return true; |
|
|
|
/* check if ip is configured on upper dev */ |
|
if (netdev_walk_all_upper_dev_rcu(dev, br_chk_addr_ip, &priv)) |
|
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 = 0; |
|
|
|
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_opt_get(br, BROPT_NEIGH_SUPPRESS_ENABLED)) { |
|
if (p && (p->flags & BR_NEIGH_SUPPRESS)) |
|
return; |
|
if (parp->ar_op != htons(ARPOP_RREQUEST) && |
|
parp->ar_op != htons(ARPOP_RREPLY) && |
|
(ipv4_is_zeronet(sip) || sip == tip)) { |
|
/* prevent flooding to neigh suppress ports */ |
|
BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1; |
|
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_opt_get(br, BROPT_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 = 1; |
|
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_opt_get(br, BROPT_NEIGH_SUPPRESS_ENABLED)) |
|
BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1; |
|
} |
|
|
|
neigh_release(n); |
|
} |
|
} |
|
#endif |
|
|
|
#if IS_ENABLED(CONFIG_IPV6) |
|
struct nd_msg *br_is_nd_neigh_msg(struct sk_buff *skb, struct nd_msg *msg) |
|
{ |
|
struct nd_msg *m; |
|
|
|
m = skb_header_pointer(skb, skb_network_offset(skb) + |
|
sizeof(struct ipv6hdr), sizeof(*msg), msg); |
|
if (!m) |
|
return NULL; |
|
|
|
if (m->icmph.icmp6_code != 0 || |
|
(m->icmph.icmp6_type != NDISC_NEIGHBOUR_SOLICITATION && |
|
m->icmph.icmp6_type != NDISC_NEIGHBOUR_ADVERTISEMENT)) |
|
return NULL; |
|
|
|
return m; |
|
} |
|
|
|
static void br_nd_send(struct net_bridge *br, struct net_bridge_port *p, |
|
struct sk_buff *request, struct neighbour *n, |
|
__be16 vlan_proto, u16 vlan_tci, struct nd_msg *ns) |
|
{ |
|
struct net_device *dev = request->dev; |
|
struct net_bridge_vlan_group *vg; |
|
struct sk_buff *reply; |
|
struct nd_msg *na; |
|
struct ipv6hdr *pip6; |
|
int na_olen = 8; /* opt hdr + ETH_ALEN for target */ |
|
int ns_olen; |
|
int i, len; |
|
u8 *daddr; |
|
u16 pvid; |
|
|
|
if (!dev) |
|
return; |
|
|
|
len = LL_RESERVED_SPACE(dev) + sizeof(struct ipv6hdr) + |
|
sizeof(*na) + na_olen + dev->needed_tailroom; |
|
|
|
reply = alloc_skb(len, GFP_ATOMIC); |
|
if (!reply) |
|
return; |
|
|
|
reply->protocol = htons(ETH_P_IPV6); |
|
reply->dev = dev; |
|
skb_reserve(reply, LL_RESERVED_SPACE(dev)); |
|
skb_push(reply, sizeof(struct ethhdr)); |
|
skb_set_mac_header(reply, 0); |
|
|
|
daddr = eth_hdr(request)->h_source; |
|
|
|
/* Do we need option processing ? */ |
|
ns_olen = request->len - (skb_network_offset(request) + |
|
sizeof(struct ipv6hdr)) - sizeof(*ns); |
|
for (i = 0; i < ns_olen - 1; i += (ns->opt[i + 1] << 3)) { |
|
if (!ns->opt[i + 1]) { |
|
kfree_skb(reply); |
|
return; |
|
} |
|
if (ns->opt[i] == ND_OPT_SOURCE_LL_ADDR) { |
|
daddr = ns->opt + i + sizeof(struct nd_opt_hdr); |
|
break; |
|
} |
|
} |
|
|
|
/* Ethernet header */ |
|
ether_addr_copy(eth_hdr(reply)->h_dest, daddr); |
|
ether_addr_copy(eth_hdr(reply)->h_source, n->ha); |
|
eth_hdr(reply)->h_proto = htons(ETH_P_IPV6); |
|
reply->protocol = htons(ETH_P_IPV6); |
|
|
|
skb_pull(reply, sizeof(struct ethhdr)); |
|
skb_set_network_header(reply, 0); |
|
skb_put(reply, sizeof(struct ipv6hdr)); |
|
|
|
/* IPv6 header */ |
|
pip6 = ipv6_hdr(reply); |
|
memset(pip6, 0, sizeof(struct ipv6hdr)); |
|
pip6->version = 6; |
|
pip6->priority = ipv6_hdr(request)->priority; |
|
pip6->nexthdr = IPPROTO_ICMPV6; |
|
pip6->hop_limit = 255; |
|
pip6->daddr = ipv6_hdr(request)->saddr; |
|
pip6->saddr = *(struct in6_addr *)n->primary_key; |
|
|
|
skb_pull(reply, sizeof(struct ipv6hdr)); |
|
skb_set_transport_header(reply, 0); |
|
|
|
na = (struct nd_msg *)skb_put(reply, sizeof(*na) + na_olen); |
|
|
|
/* Neighbor Advertisement */ |
|
memset(na, 0, sizeof(*na) + na_olen); |
|
na->icmph.icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT; |
|
na->icmph.icmp6_router = (n->flags & NTF_ROUTER) ? 1 : 0; |
|
na->icmph.icmp6_override = 1; |
|
na->icmph.icmp6_solicited = 1; |
|
na->target = ns->target; |
|
ether_addr_copy(&na->opt[2], n->ha); |
|
na->opt[0] = ND_OPT_TARGET_LL_ADDR; |
|
na->opt[1] = na_olen >> 3; |
|
|
|
na->icmph.icmp6_cksum = csum_ipv6_magic(&pip6->saddr, |
|
&pip6->daddr, |
|
sizeof(*na) + na_olen, |
|
IPPROTO_ICMPV6, |
|
csum_partial(na, sizeof(*na) + na_olen, 0)); |
|
|
|
pip6->payload_len = htons(sizeof(*na) + na_olen); |
|
|
|
skb_push(reply, sizeof(struct ipv6hdr)); |
|
skb_push(reply, sizeof(struct ethhdr)); |
|
|
|
reply->ip_summed = CHECKSUM_UNNECESSARY; |
|
|
|
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(reply, vlan_proto, vlan_tci); |
|
|
|
netdev_dbg(dev, "nd send dev %s dst %pI6 dst_hw %pM src %pI6 src_hw %pM\n", |
|
dev->name, &pip6->daddr, daddr, &pip6->saddr, n->ha); |
|
|
|
if (p) { |
|
dev_queue_xmit(reply); |
|
} else { |
|
skb_reset_mac_header(reply); |
|
__skb_pull(reply, skb_network_offset(reply)); |
|
reply->ip_summed = CHECKSUM_UNNECESSARY; |
|
reply->pkt_type = PACKET_HOST; |
|
|
|
netif_rx_ni(reply); |
|
} |
|
} |
|
|
|
static int br_chk_addr_ip6(struct net_device *dev, |
|
struct netdev_nested_priv *priv) |
|
{ |
|
struct in6_addr *addr = (struct in6_addr *)priv->data; |
|
|
|
if (ipv6_chk_addr(dev_net(dev), addr, dev, 0)) |
|
return 1; |
|
|
|
return 0; |
|
} |
|
|
|
static bool br_is_local_ip6(struct net_device *dev, struct in6_addr *addr) |
|
|
|
{ |
|
struct netdev_nested_priv priv = { |
|
.data = (void *)addr, |
|
}; |
|
|
|
if (br_chk_addr_ip6(dev, &priv)) |
|
return true; |
|
|
|
/* check if ip is configured on upper dev */ |
|
if (netdev_walk_all_upper_dev_rcu(dev, br_chk_addr_ip6, &priv)) |
|
return true; |
|
|
|
return false; |
|
} |
|
|
|
void br_do_suppress_nd(struct sk_buff *skb, struct net_bridge *br, |
|
u16 vid, struct net_bridge_port *p, struct nd_msg *msg) |
|
{ |
|
struct net_device *dev = br->dev; |
|
struct net_device *vlandev = NULL; |
|
struct in6_addr *saddr, *daddr; |
|
struct ipv6hdr *iphdr; |
|
struct neighbour *n; |
|
|
|
BR_INPUT_SKB_CB(skb)->proxyarp_replied = 0; |
|
|
|
if (p && (p->flags & BR_NEIGH_SUPPRESS)) |
|
return; |
|
|
|
if (msg->icmph.icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT && |
|
!msg->icmph.icmp6_solicited) { |
|
/* prevent flooding to neigh suppress ports */ |
|
BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1; |
|
return; |
|
} |
|
|
|
if (msg->icmph.icmp6_type != NDISC_NEIGHBOUR_SOLICITATION) |
|
return; |
|
|
|
iphdr = ipv6_hdr(skb); |
|
saddr = &iphdr->saddr; |
|
daddr = &iphdr->daddr; |
|
|
|
if (ipv6_addr_any(saddr) || !ipv6_addr_cmp(saddr, daddr)) { |
|
/* prevent flooding to neigh suppress ports */ |
|
BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1; |
|
return; |
|
} |
|
|
|
if (vid != 0) { |
|
/* build neigh table lookup on the vlan device */ |
|
vlandev = __vlan_find_dev_deep_rcu(br->dev, skb->vlan_proto, |
|
vid); |
|
if (!vlandev) |
|
return; |
|
} else { |
|
vlandev = dev; |
|
} |
|
|
|
if (br_is_local_ip6(vlandev, &msg->target)) { |
|
/* its our own ip, so don't proxy reply |
|
* and don't forward to arp suppress ports |
|
*/ |
|
BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1; |
|
return; |
|
} |
|
|
|
n = neigh_lookup(ipv6_stub->nd_tbl, &msg->target, 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 (f->dst && (f->dst->flags & BR_NEIGH_SUPPRESS)) { |
|
if (vid != 0) |
|
br_nd_send(br, p, skb, n, |
|
skb->vlan_proto, |
|
skb_vlan_tag_get(skb), msg); |
|
else |
|
br_nd_send(br, p, skb, n, 0, 0, msg); |
|
replied = true; |
|
} |
|
|
|
/* If we have replied or as long as we know the |
|
* mac, indicate to NEIGH_SUPPRESS ports that we |
|
* have replied |
|
*/ |
|
if (replied || |
|
br_opt_get(br, BROPT_NEIGH_SUPPRESS_ENABLED)) |
|
BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1; |
|
} |
|
neigh_release(n); |
|
} |
|
} |
|
#endif
|
|
|