X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=include%2Fnet%2Finet_ecn.h;h=d599c6bfbb86bc5eb0e83f91f9f7fb417d4631f2;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=55dc2b3be699e6b34b1b456df74a494ae5e30f8f;hpb=5273a3df6485dc2ad6aa7ddd441b9a21970f003b;p=linux-2.6.git

diff --git a/include/net/inet_ecn.h b/include/net/inet_ecn.h
index 55dc2b3be..d599c6bfb 100644
--- a/include/net/inet_ecn.h
+++ b/include/net/inet_ecn.h
@@ -2,67 +2,129 @@
 #define _INET_ECN_H_
 
 #include <linux/ip.h>
+#include <linux/skbuff.h>
+
+#include <net/inet_sock.h>
+#include <net/dsfield.h>
+
+enum {
+	INET_ECN_NOT_ECT = 0,
+	INET_ECN_ECT_1 = 1,
+	INET_ECN_ECT_0 = 2,
+	INET_ECN_CE = 3,
+	INET_ECN_MASK = 3,
+};
 
 static inline int INET_ECN_is_ce(__u8 dsfield)
 {
-	return (dsfield&3) == 3;
+	return (dsfield & INET_ECN_MASK) == INET_ECN_CE;
 }
 
-static inline int INET_ECN_is_not_ce(__u8 dsfield)
+static inline int INET_ECN_is_not_ect(__u8 dsfield)
 {
-	return (dsfield&3) == 2;
+	return (dsfield & INET_ECN_MASK) == INET_ECN_NOT_ECT;
 }
 
 static inline int INET_ECN_is_capable(__u8 dsfield)
 {
-	return (dsfield&2);
+	return (dsfield & INET_ECN_ECT_0);
 }
 
 static inline __u8 INET_ECN_encapsulate(__u8 outer, __u8 inner)
 {
-	outer &= ~3;
-	if (INET_ECN_is_capable(inner))
-		outer |= (inner & 3);
+	outer &= ~INET_ECN_MASK;
+	outer |= !INET_ECN_is_ce(inner) ? (inner & INET_ECN_MASK) :
+					  INET_ECN_ECT_0;
 	return outer;
 }
 
-#define	INET_ECN_xmit(sk) do { inet_sk(sk)->tos |= 2; } while (0)
-#define	INET_ECN_dontxmit(sk) do { inet_sk(sk)->tos &= ~3; } while (0)
+#define	INET_ECN_xmit(sk) do { inet_sk(sk)->tos |= INET_ECN_ECT_0; } while (0)
+#define	INET_ECN_dontxmit(sk) \
+	do { inet_sk(sk)->tos &= ~INET_ECN_MASK; } while (0)
 
-#define IP6_ECN_flow_init(label) do {	\
-      (label) &= ~htonl(3<<20);		\
+#define IP6_ECN_flow_init(label) do {		\
+      (label) &= ~htonl(INET_ECN_MASK << 20);	\
     } while (0)
 
-#define	IP6_ECN_flow_xmit(sk, label) do {			\
-	if (INET_ECN_is_capable(inet_sk(sk)->tos))		\
-		(label) |= __constant_htons(2 << 4);		\
+#define	IP6_ECN_flow_xmit(sk, label) do {				\
+	if (INET_ECN_is_capable(inet_sk(sk)->tos))			\
+		(label) |= __constant_htons(INET_ECN_ECT_0 << 4);	\
     } while (0)
 
-static inline void IP_ECN_set_ce(struct iphdr *iph)
+static inline int IP_ECN_set_ce(struct iphdr *iph)
 {
 	u32 check = iph->check;
-	check += __constant_htons(0xFFFE);
+	u32 ecn = (iph->tos + 1) & INET_ECN_MASK;
+
+	/*
+	 * After the last operation we have (in binary):
+	 * INET_ECN_NOT_ECT => 01
+	 * INET_ECN_ECT_1   => 10
+	 * INET_ECN_ECT_0   => 11
+	 * INET_ECN_CE      => 00
+	 */
+	if (!(ecn & 2))
+		return !ecn;
+
+	/*
+	 * The following gives us:
+	 * INET_ECN_ECT_1 => check += htons(0xFFFD)
+	 * INET_ECN_ECT_0 => check += htons(0xFFFE)
+	 */
+	check += htons(0xFFFB) + htons(ecn);
+
 	iph->check = check + (check>=0xFFFF);
-	iph->tos |= 1;
+	iph->tos |= INET_ECN_CE;
+	return 1;
 }
 
 static inline void IP_ECN_clear(struct iphdr *iph)
 {
-	iph->tos &= ~3;
+	iph->tos &= ~INET_ECN_MASK;
+}
+
+static inline void ipv4_copy_dscp(struct iphdr *outer, struct iphdr *inner)
+{
+	u32 dscp = ipv4_get_dsfield(outer) & ~INET_ECN_MASK;
+	ipv4_change_dsfield(inner, INET_ECN_MASK, dscp);
 }
 
 struct ipv6hdr;
 
-static inline void IP6_ECN_set_ce(struct ipv6hdr *iph)
+static inline int IP6_ECN_set_ce(struct ipv6hdr *iph)
 {
-	*(u32*)iph |= htonl(1<<20);
+	if (INET_ECN_is_not_ect(ipv6_get_dsfield(iph)))
+		return 0;
+	*(u32*)iph |= htonl(INET_ECN_CE << 20);
+	return 1;
 }
 
 static inline void IP6_ECN_clear(struct ipv6hdr *iph)
 {
-	*(u32*)iph &= ~htonl(3<<20);
+	*(u32*)iph &= ~htonl(INET_ECN_MASK << 20);
 }
 
-#define ip6_get_dsfield(iph) ((ntohs(*(u16*)(iph)) >> 4) & 0xFF)
+static inline void ipv6_copy_dscp(struct ipv6hdr *outer, struct ipv6hdr *inner)
+{
+	u32 dscp = ipv6_get_dsfield(outer) & ~INET_ECN_MASK;
+	ipv6_change_dsfield(inner, INET_ECN_MASK, dscp);
+}
+
+static inline int INET_ECN_set_ce(struct sk_buff *skb)
+{
+	switch (skb->protocol) {
+	case __constant_htons(ETH_P_IP):
+		if (skb->nh.raw + sizeof(struct iphdr) <= skb->tail)
+			return IP_ECN_set_ce(skb->nh.iph);
+		break;
+
+	case __constant_htons(ETH_P_IPV6):
+		if (skb->nh.raw + sizeof(struct ipv6hdr) <= skb->tail)
+			return IP6_ECN_set_ce(skb->nh.ipv6h);
+		break;
+	}
+
+	return 0;
+}
 
 #endif