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Diffstat (limited to 'net/ipv6/ip6_checksum.c')
-rw-r--r--net/ipv6/ip6_checksum.c63
1 files changed, 44 insertions, 19 deletions
diff --git a/net/ipv6/ip6_checksum.c b/net/ipv6/ip6_checksum.c
index ee7a97f510c..9a4d7322fb2 100644
--- a/net/ipv6/ip6_checksum.c
+++ b/net/ipv6/ip6_checksum.c
@@ -75,25 +75,50 @@ int udp6_csum_init(struct sk_buff *skb, struct udphdr *uh, int proto)
return err;
}
- if (uh->check == 0) {
- /* RFC 2460 section 8.1 says that we SHOULD log
- this error. Well, it is reasonable.
- */
- LIMIT_NETDEBUG(KERN_INFO "IPv6: udp checksum is 0 for [%pI6c]:%u->[%pI6c]:%u\n",
- &ipv6_hdr(skb)->saddr, ntohs(uh->source),
- &ipv6_hdr(skb)->daddr, ntohs(uh->dest));
- return 1;
- }
- if (skb->ip_summed == CHECKSUM_COMPLETE &&
- !csum_ipv6_magic(&ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
- skb->len, proto, skb->csum))
- skb->ip_summed = CHECKSUM_UNNECESSARY;
+ /* To support RFC 6936 (allow zero checksum in UDP/IPV6 for tunnels)
+ * we accept a checksum of zero here. When we find the socket
+ * for the UDP packet we'll check if that socket allows zero checksum
+ * for IPv6 (set by socket option).
+ */
+ return skb_checksum_init_zero_check(skb, proto, uh->check,
+ ip6_compute_pseudo);
+}
+EXPORT_SYMBOL(udp6_csum_init);
+
+/* Function to set UDP checksum for an IPv6 UDP packet. This is intended
+ * for the simple case like when setting the checksum for a UDP tunnel.
+ */
+void udp6_set_csum(bool nocheck, struct sk_buff *skb,
+ const struct in6_addr *saddr,
+ const struct in6_addr *daddr, int len)
+{
+ struct udphdr *uh = udp_hdr(skb);
+
+ if (nocheck)
+ uh->check = 0;
+ else if (skb_is_gso(skb))
+ uh->check = ~udp_v6_check(len, saddr, daddr, 0);
+ else if (skb_dst(skb) && skb_dst(skb)->dev &&
+ (skb_dst(skb)->dev->features & NETIF_F_IPV6_CSUM)) {
- if (!skb_csum_unnecessary(skb))
- skb->csum = ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
- &ipv6_hdr(skb)->daddr,
- skb->len, proto, 0));
+ BUG_ON(skb->ip_summed == CHECKSUM_PARTIAL);
- return 0;
+ skb->ip_summed = CHECKSUM_PARTIAL;
+ skb->csum_start = skb_transport_header(skb) - skb->head;
+ skb->csum_offset = offsetof(struct udphdr, check);
+ uh->check = ~udp_v6_check(len, saddr, daddr, 0);
+ } else {
+ __wsum csum;
+
+ BUG_ON(skb->ip_summed == CHECKSUM_PARTIAL);
+
+ uh->check = 0;
+ csum = skb_checksum(skb, 0, len, 0);
+ uh->check = udp_v6_check(len, saddr, daddr, csum);
+ if (uh->check == 0)
+ uh->check = CSUM_MANGLED_0;
+
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+ }
}
-EXPORT_SYMBOL(udp6_csum_init);
+EXPORT_SYMBOL(udp6_set_csum);