static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh,
__be32 *addr, __be32 new_addr)
{
int transport_len = skb->len - skb_transport_offset(skb);
if (nh->protocol == IPPROTO_TCP) {
if (likely(transport_len >= sizeof(struct tcphdr)))
inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb,
*addr, new_addr, 1);
} else if (nh->protocol == IPPROTO_UDP) {
if (likely(transport_len >= sizeof(struct udphdr))) {
struct udphdr *uh = udp_hdr(skb);
if (uh->check ||
get_ip_summed(skb) == OVS_CSUM_PARTIAL) {
inet_proto_csum_replace4(&uh->check, skb,
*addr, new_addr, 1);
if (!uh->check)
uh->check = CSUM_MANGLED_0;
}
}
}
csum_replace4(&nh->check, *addr, new_addr);
skb_clear_rxhash(skb);
*addr = new_addr;
}
/**
* ovs_tnl_rcv - ingress point for generic tunnel code
*
* @vport: port this packet was received on
* @skb: received packet
* @tos: ToS from encapsulating IP packet, used to copy ECN bits
*
* Must be called with rcu_read_lock.
*
* Packets received by this function are in the following state:
* - skb->data points to the inner Ethernet header.
* - The inner Ethernet header is in the linear data area.
* - skb->csum does not include the inner Ethernet header.
* - The layer pointers are undefined.
*/
void ovs_tnl_rcv(struct vport *vport, struct sk_buff *skb,
struct ovs_key_ipv4_tunnel *tun_key)
{
struct ethhdr *eh;
skb_reset_mac_header(skb);
eh = eth_hdr(skb);
if (likely(ntohs(eh->h_proto) >= ETH_P_802_3_MIN))
skb->protocol = eh->h_proto;
else
skb->protocol = htons(ETH_P_802_2);
skb_dst_drop(skb);
nf_reset(skb);
skb_clear_rxhash(skb);
secpath_reset(skb);
vlan_set_tci(skb, 0);
if (unlikely(compute_ip_summed(skb, false))) {
kfree_skb(skb);
return;
}
ovs_vport_receive(vport, skb, tun_key);
}
/* Must follow make_writable() since that can move the skb data. */
static void set_tp_port(struct sk_buff *skb, __be16 *port,
__be16 new_port, __sum16 *check)
{
inet_proto_csum_replace2(check, skb, *port, new_port, 0);
*port = new_port;
skb_clear_rxhash(skb);
}
int iptunnel_pull_header(struct sk_buff *skb, int hdr_len, __be16 inner_proto)
{
if (unlikely(!pskb_may_pull(skb, hdr_len)))
return -ENOMEM;
skb_pull_rcsum(skb, hdr_len);
if (inner_proto == htons(ETH_P_TEB)) {
struct ethhdr *eh;
if (unlikely(!pskb_may_pull(skb, ETH_HLEN)))
return -ENOMEM;
eh = (struct ethhdr *)skb->data;
if (likely(ntohs(eh->h_proto) >= ETH_P_802_3_MIN))
skb->protocol = eh->h_proto;
else
skb->protocol = htons(ETH_P_802_2);
} else {
skb->protocol = inner_proto;
}
nf_reset(skb);
secpath_reset(skb);
skb_clear_rxhash(skb);
skb_dst_drop(skb);
vlan_set_tci(skb, 0);
skb_set_queue_mapping(skb, 0);
skb->pkt_type = PACKET_HOST;
return 0;
}
static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto,
__be32 addr[4], const __be32 new_addr[4],
bool recalculate_csum)
{
if (recalculate_csum)
update_ipv6_checksum(skb, l4_proto, addr, new_addr);
skb_clear_rxhash(skb);
memcpy(addr, new_addr, sizeof(__be32[4]));
}
static void set_udp_port(struct sk_buff *skb, __be16 *port, __be16 new_port)
{
struct udphdr *uh = udp_hdr(skb);
if (uh->check && get_ip_summed(skb) != OVS_CSUM_PARTIAL) {
set_tp_port(skb, port, new_port, &uh->check);
if (!uh->check)
uh->check = CSUM_MANGLED_0;
} else {
*port = new_port;
skb_clear_rxhash(skb);
}
}
int iptunnel_xmit(struct net *net, struct rtable *rt,
struct sk_buff *skb,
__be32 src, __be32 dst, __u8 proto,
__u8 tos, __u8 ttl, __be16 df)
{
int pkt_len = skb->len;
struct iphdr *iph;
int err;
nf_reset(skb);
secpath_reset(skb);
skb_clear_rxhash(skb);
skb_dst_drop(skb);
skb_dst_set(skb, &rt_dst(rt));
#if 0
/* Do not clear ovs_skb_cb. It will be done in gso code. */
memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
#endif
/* Push down and install the IP header. */
__skb_push(skb, sizeof(struct iphdr));
skb_reset_network_header(skb);
iph = ip_hdr(skb);
iph->version = 4;
iph->ihl = sizeof(struct iphdr) >> 2;
iph->frag_off = df;
iph->protocol = proto;
iph->tos = tos;
iph->daddr = dst;
iph->saddr = src;
iph->ttl = ttl;
tunnel_ip_select_ident(skb,
(const struct iphdr *)skb_inner_network_header(skb),
&rt_dst(rt));
err = ip_local_out(skb);
if (unlikely(net_xmit_eval(err)))
pkt_len = 0;
return pkt_len;
}
