/* Replicate the checks that IPv6 does on packet reception and pass the packet
* to ip6tables.
*/
unsigned int br_nf_pre_routing_ipv6(const struct nf_hook_ops *ops,
struct sk_buff *skb,
const struct nf_hook_state *state)
{
struct nf_bridge_info *nf_bridge;
if (br_validate_ipv6(skb))
return NF_DROP;
nf_bridge_put(skb->nf_bridge);
if (!nf_bridge_alloc(skb))
return NF_DROP;
if (!setup_pre_routing(skb))
return NF_DROP;
nf_bridge = nf_bridge_info_get(skb);
nf_bridge->ipv6_daddr = ipv6_hdr(skb)->daddr;
skb->protocol = htons(ETH_P_IPV6);
NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING, state->sk, skb,
skb->dev, NULL,
br_nf_pre_routing_finish_ipv6);
return NF_STOLEN;
}
static int br_nf_dev_queue_xmit(struct net *net, struct sock *sk, struct sk_buff *skb)
{
struct nf_bridge_info *nf_bridge;
unsigned int mtu_reserved;
mtu_reserved = nf_bridge_mtu_reduction(skb);
if (skb_is_gso(skb) || skb->len + mtu_reserved <= skb->dev->mtu) {
nf_bridge_info_free(skb);
return br_dev_queue_push_xmit(net, sk, skb);
}
nf_bridge = nf_bridge_info_get(skb);
/* This is wrong! We should preserve the original fragment
* boundaries by preserving frag_list rather than refragmenting.
*/
if (IS_ENABLED(CONFIG_NF_DEFRAG_IPV4) &&
skb->protocol == htons(ETH_P_IP)) {
struct brnf_frag_data *data;
if (br_validate_ipv4(net, skb))
goto drop;
IPCB(skb)->frag_max_size = nf_bridge->frag_max_size;
nf_bridge_update_protocol(skb);
data = this_cpu_ptr(&brnf_frag_data_storage);
data->vlan_tci = skb->vlan_tci;
data->vlan_proto = skb->vlan_proto;
data->encap_size = nf_bridge_encap_header_len(skb);
data->size = ETH_HLEN + data->encap_size;
skb_copy_from_linear_data_offset(skb, -data->size, data->mac,
data->size);
return br_nf_ip_fragment(net, sk, skb, br_nf_push_frag_xmit);
}
if (IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) &&
skb->protocol == htons(ETH_P_IPV6)) {
const struct nf_ipv6_ops *v6ops = nf_get_ipv6_ops();
struct brnf_frag_data *data;
if (br_validate_ipv6(net, skb))
goto drop;
IP6CB(skb)->frag_max_size = nf_bridge->frag_max_size;
nf_bridge_update_protocol(skb);
data = this_cpu_ptr(&brnf_frag_data_storage);
data->encap_size = nf_bridge_encap_header_len(skb);
data->size = ETH_HLEN + data->encap_size;
skb_copy_from_linear_data_offset(skb, -data->size, data->mac,
data->size);
if (v6ops)
return v6ops->fragment(net, sk, skb, br_nf_push_frag_xmit);
kfree_skb(skb);
return -EMSGSIZE;
}
nf_bridge_info_free(skb);
return br_dev_queue_push_xmit(net, sk, skb);
drop:
kfree_skb(skb);
return 0;
}
/* This is the 'purely bridged' case. For IP, we pass the packet to
* netfilter with indev and outdev set to the bridge device,
* but we are still able to filter on the 'real' indev/outdev
* because of the physdev module. For ARP, indev and outdev are the
* bridge ports. */
static unsigned int br_nf_forward_ip(void *priv,
struct sk_buff *skb,
const struct nf_hook_state *state)
{
struct nf_bridge_info *nf_bridge;
struct net_device *parent;
u_int8_t pf;
if (!skb->nf_bridge)
return NF_ACCEPT;
/* Need exclusive nf_bridge_info since we might have multiple
* different physoutdevs. */
if (!nf_bridge_unshare(skb))
return NF_DROP;
nf_bridge = nf_bridge_info_get(skb);
if (!nf_bridge)
return NF_DROP;
parent = bridge_parent(state->out);
if (!parent)
return NF_DROP;
if (IS_IP(skb) || IS_VLAN_IP(skb) || IS_PPPOE_IP(skb))
pf = NFPROTO_IPV4;
else if (IS_IPV6(skb) || IS_VLAN_IPV6(skb) || IS_PPPOE_IPV6(skb))
pf = NFPROTO_IPV6;
else
return NF_ACCEPT;
nf_bridge_pull_encap_header(skb);
if (skb->pkt_type == PACKET_OTHERHOST) {
skb->pkt_type = PACKET_HOST;
nf_bridge->pkt_otherhost = true;
}
if (pf == NFPROTO_IPV4) {
if (br_validate_ipv4(state->net, skb))
return NF_DROP;
IPCB(skb)->frag_max_size = nf_bridge->frag_max_size;
}
if (pf == NFPROTO_IPV6) {
if (br_validate_ipv6(state->net, skb))
return NF_DROP;
IP6CB(skb)->frag_max_size = nf_bridge->frag_max_size;
}
nf_bridge->physoutdev = skb->dev;
if (pf == NFPROTO_IPV4)
skb->protocol = htons(ETH_P_IP);
else
skb->protocol = htons(ETH_P_IPV6);
NF_HOOK(pf, NF_INET_FORWARD, state->net, NULL, skb,
brnf_get_logical_dev(skb, state->in),
parent, br_nf_forward_finish);
return NF_STOLEN;
}
