linux/net/ipv6/ip6_udp_tunnel.c
Alexander Duyck f3750817a9 ip6_udp_tunnel: Fix checksum calculation
The UDP checksum calculation for VXLAN tunnels is currently using the
socket addresses instead of the actual packet source and destination
addresses.  As a result the checksum calculated is incorrect in some
cases.

Also uh->check was being set twice, first it was set to 0, and then it is
set again in udp6_set_csum.  This change removes the redundant assignment
to 0.

Fixes: acbf74a7 ("vxlan: Refactor vxlan driver to make use of the common UDP tunnel functions.")

Cc: Andy Zhou <azhou@nicira.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-25 14:12:12 -05:00

106 lines
2.6 KiB
C

#include <linux/module.h>
#include <linux/errno.h>
#include <linux/socket.h>
#include <linux/udp.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/in6.h>
#include <net/udp.h>
#include <net/udp_tunnel.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>
#include <net/ip6_tunnel.h>
#include <net/ip6_checksum.h>
int udp_sock_create6(struct net *net, struct udp_port_cfg *cfg,
struct socket **sockp)
{
struct sockaddr_in6 udp6_addr;
int err;
struct socket *sock = NULL;
err = sock_create_kern(AF_INET6, SOCK_DGRAM, 0, &sock);
if (err < 0)
goto error;
sk_change_net(sock->sk, net);
udp6_addr.sin6_family = AF_INET6;
memcpy(&udp6_addr.sin6_addr, &cfg->local_ip6,
sizeof(udp6_addr.sin6_addr));
udp6_addr.sin6_port = cfg->local_udp_port;
err = kernel_bind(sock, (struct sockaddr *)&udp6_addr,
sizeof(udp6_addr));
if (err < 0)
goto error;
if (cfg->peer_udp_port) {
udp6_addr.sin6_family = AF_INET6;
memcpy(&udp6_addr.sin6_addr, &cfg->peer_ip6,
sizeof(udp6_addr.sin6_addr));
udp6_addr.sin6_port = cfg->peer_udp_port;
err = kernel_connect(sock,
(struct sockaddr *)&udp6_addr,
sizeof(udp6_addr), 0);
}
if (err < 0)
goto error;
udp_set_no_check6_tx(sock->sk, !cfg->use_udp6_tx_checksums);
udp_set_no_check6_rx(sock->sk, !cfg->use_udp6_rx_checksums);
*sockp = sock;
return 0;
error:
if (sock) {
kernel_sock_shutdown(sock, SHUT_RDWR);
sk_release_kernel(sock->sk);
}
*sockp = NULL;
return err;
}
EXPORT_SYMBOL_GPL(udp_sock_create6);
int udp_tunnel6_xmit_skb(struct socket *sock, struct dst_entry *dst,
struct sk_buff *skb, struct net_device *dev,
struct in6_addr *saddr, struct in6_addr *daddr,
__u8 prio, __u8 ttl, __be16 src_port, __be16 dst_port)
{
struct udphdr *uh;
struct ipv6hdr *ip6h;
struct sock *sk = sock->sk;
__skb_push(skb, sizeof(*uh));
skb_reset_transport_header(skb);
uh = udp_hdr(skb);
uh->dest = dst_port;
uh->source = src_port;
uh->len = htons(skb->len);
memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED
| IPSKB_REROUTED);
skb_dst_set(skb, dst);
udp6_set_csum(udp_get_no_check6_tx(sk), skb, saddr, daddr, skb->len);
__skb_push(skb, sizeof(*ip6h));
skb_reset_network_header(skb);
ip6h = ipv6_hdr(skb);
ip6_flow_hdr(ip6h, prio, htonl(0));
ip6h->payload_len = htons(skb->len);
ip6h->nexthdr = IPPROTO_UDP;
ip6h->hop_limit = ttl;
ip6h->daddr = *daddr;
ip6h->saddr = *saddr;
ip6tunnel_xmit(skb, dev);
return 0;
}
EXPORT_SYMBOL_GPL(udp_tunnel6_xmit_skb);
MODULE_LICENSE("GPL");