1 files changed, 55 insertions, 2 deletions

diff --git a/include/net/inet_ecn.h b/include/net/inet_ecn.h
index c8e2bebd8d93..0f0d1efe06dd 100644
--- a/include/net/inet_ecn.h
+++ b/include/net/inet_ecn.h
@@ -99,6 +99,20 @@ static inline int IP_ECN_set_ce(struct iphdr *iph)
 	return 1;
 }
 
+static inline int IP_ECN_set_ect1(struct iphdr *iph)
+{
+	u32 check = (__force u32)iph->check;
+
+	if ((iph->tos & INET_ECN_MASK) != INET_ECN_ECT_0)
+		return 0;
+
+	check += (__force u16)htons(0x100);
+
+	iph->check = (__force __sum16)(check + (check>=0xFFFF));
+	iph->tos ^= INET_ECN_MASK;
+	return 1;
+}
+
 static inline void IP_ECN_clear(struct iphdr *iph)
 {
 	iph->tos &= ~INET_ECN_MASK;
@@ -134,6 +148,22 @@ static inline int IP6_ECN_set_ce(struct sk_buff *skb, struct ipv6hdr *iph)
 	return 1;
 }
 
+static inline int IP6_ECN_set_ect1(struct sk_buff *skb, struct ipv6hdr *iph)
+{
+	__be32 from, to;
+
+	if ((ipv6_get_dsfield(iph) & INET_ECN_MASK) != INET_ECN_ECT_0)
+		return 0;
+
+	from = *(__be32 *)iph;
+	to = from ^ htonl(INET_ECN_MASK << 20);
+	*(__be32 *)iph = to;
+	if (skb->ip_summed == CHECKSUM_COMPLETE)
+		skb->csum = csum_add(csum_sub(skb->csum, (__force __wsum)from),
+				     (__force __wsum)to);
+	return 1;
+}
+
 static inline void ipv6_copy_dscp(unsigned int dscp, struct ipv6hdr *inner)
 {
 	dscp &= ~INET_ECN_MASK;
@@ -159,6 +189,25 @@ static inline int INET_ECN_set_ce(struct sk_buff *skb)
 	return 0;
 }
 
+static inline int INET_ECN_set_ect1(struct sk_buff *skb)
+{
+	switch (skb->protocol) {
+	case cpu_to_be16(ETH_P_IP):
+		if (skb_network_header(skb) + sizeof(struct iphdr) <=
+		    skb_tail_pointer(skb))
+			return IP_ECN_set_ect1(ip_hdr(skb));
+		break;
+
+	case cpu_to_be16(ETH_P_IPV6):
+		if (skb_network_header(skb) + sizeof(struct ipv6hdr) <=
+		    skb_tail_pointer(skb))
+			return IP6_ECN_set_ect1(skb, ipv6_hdr(skb));
+		break;
+	}
+
+	return 0;
+}
+
 /*
  * RFC 6040 4.2
  *  To decapsulate the inner header at the tunnel egress, a compliant
@@ -208,8 +257,12 @@ static inline int INET_ECN_decapsulate(struct sk_buff *skb,
 	int rc;
 
 	rc = __INET_ECN_decapsulate(outer, inner, &set_ce);
-	if (!rc && set_ce)
-		INET_ECN_set_ce(skb);
+	if (!rc) {
+		if (set_ce)
+			INET_ECN_set_ce(skb);
+		else if ((outer & INET_ECN_MASK) == INET_ECN_ECT_1)
+			INET_ECN_set_ect1(skb);
+	}
 
 	return rc;
 }