l2tp: call udp{6}_set_csum

Call common functions to set checksum for UDP tunnel.

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 49 deletions

diff --git a/net/l2tp/l2tp_core.c b/net/l2tp/l2tp_core.c
index 379558014b60..bea259043205 100644
--- a/net/l2tp/l2tp_core.c
+++ b/net/l2tp/l2tp_core.c
@@ -1095,33 +1095,6 @@ static int l2tp_xmit_core(struct l2tp_session *session, struct sk_buff *skb,
         return 0;
 }
 
-#if IS_ENABLED(CONFIG_IPV6)
-static void l2tp_xmit_ipv6_csum(struct sock *sk, struct sk_buff *skb,
-                                int udp_len)
-{
-        struct ipv6_pinfo *np = inet6_sk(sk);
-        struct udphdr *uh = udp_hdr(skb);
-
-        if (udp_get_no_check6_tx(sk))
-                skb->ip_summed = CHECKSUM_NONE;
-        else if (!skb_dst(skb) || !skb_dst(skb)->dev ||
-            !(skb_dst(skb)->dev->features & NETIF_F_IPV6_CSUM)) {
-                __wsum csum = skb_checksum(skb, 0, udp_len, 0);
-                skb->ip_summed = CHECKSUM_UNNECESSARY;
-                uh->check = csum_ipv6_magic(&np->saddr, &sk->sk_v6_daddr, udp_len,
-                                            IPPROTO_UDP, csum);
-                if (uh->check == 0)
-                        uh->check = CSUM_MANGLED_0;
-        } else {
-                skb->ip_summed = CHECKSUM_PARTIAL;
-                skb->csum_start = skb_transport_header(skb) - skb->head;
-                skb->csum_offset = offsetof(struct udphdr, check);
-                uh->check = ~csum_ipv6_magic(&np->saddr, &sk->sk_v6_daddr,
-                                             udp_len, IPPROTO_UDP, 0);
-        }
-}
-#endif
-
 /* If caller requires the skb to have a ppp header, the header must be
  * inserted in the skb data before calling this function.
  */
@@ -1133,7 +1106,6 @@ int l2tp_xmit_skb(struct l2tp_session *session, struct sk_buff *skb, int hdr_len
         struct flowi *fl;
         struct udphdr *uh;
         struct inet_sock *inet;
-        __wsum csum;
         int headroom;
         int uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0;
         int udp_len;
@@ -1182,33 +1154,17 @@ int l2tp_xmit_skb(struct l2tp_session *session, struct sk_buff *skb, int hdr_len
                 uh->dest = inet->inet_dport;
                 udp_len = uhlen + hdr_len + data_len;
                 uh->len = htons(udp_len);
-                uh->check = 0;
 
                 /* Calculate UDP checksum if configured to do so */
 #if IS_ENABLED(CONFIG_IPV6)
                 if (sk->sk_family == PF_INET6 && !tunnel->v4mapped)
-                        l2tp_xmit_ipv6_csum(sk, skb, udp_len);
+                        udp6_set_csum(udp_get_no_check6_tx(sk),
+                                      skb, &inet6_sk(sk)->saddr,
+                                      &sk->sk_v6_daddr, udp_len);
                 else
 #endif
-                if (sk->sk_no_check_tx)
-                        skb->ip_summed = CHECKSUM_NONE;
-                else if ((skb_dst(skb) && skb_dst(skb)->dev) &&
-                         (!(skb_dst(skb)->dev->features & NETIF_F_V4_CSUM))) {
-                        skb->ip_summed = CHECKSUM_COMPLETE;
-                        csum = skb_checksum(skb, 0, udp_len, 0);
-                        uh->check = csum_tcpudp_magic(inet->inet_saddr,
-                                                      inet->inet_daddr,
-                                                      udp_len, IPPROTO_UDP, csum);
-                        if (uh->check == 0)
-                                uh->check = CSUM_MANGLED_0;
-                } else {
-                        skb->ip_summed = CHECKSUM_PARTIAL;
-                        skb->csum_start = skb_transport_header(skb) - skb->head;
-                        skb->csum_offset = offsetof(struct udphdr, check);
-                        uh->check = ~csum_tcpudp_magic(inet->inet_saddr,
-                                                       inet->inet_daddr,
-                                                       udp_len, IPPROTO_UDP, 0);
-                }
+                udp_set_csum(sk->sk_no_check_tx, skb, inet->inet_saddr,
+                             inet->inet_daddr, udp_len);
                 break;
 
         case L2TP_ENCAPTYPE_IP: