Creation of Cybook 2416 (actually Gen4) repository

include/net/inet_ecn.h

@@ -0,0 +1,130 @@
+#ifndef _INET_ECN_H_
+#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 & INET_ECN_MASK) == INET_ECN_CE;
+}
+
+static inline int INET_ECN_is_not_ect(__u8 dsfield)
+{
+	return (dsfield & INET_ECN_MASK) == INET_ECN_NOT_ECT;
+}
+
+static inline int INET_ECN_is_capable(__u8 dsfield)
+{
+	return (dsfield & INET_ECN_ECT_0);
+}
+
+static inline __u8 INET_ECN_encapsulate(__u8 outer, __u8 inner)
+{
+	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 |= 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(INET_ECN_MASK << 20);	\
+    } while (0)
+
+#define	IP6_ECN_flow_xmit(sk, label) do {				\
+	if (INET_ECN_is_capable(inet_sk(sk)->tos))			\
+		(label) |= htonl(INET_ECN_ECT_0 << 20);			\
+    } while (0)
+
+static inline int IP_ECN_set_ce(struct iphdr *iph)
+{
+	u32 check = (__force u32)iph->check;
+	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 += (__force u16)htons(0xFFFB) + (__force u16)htons(ecn);
+
+	iph->check = (__force __sum16)(check + (check>=0xFFFF));
+	iph->tos |= INET_ECN_CE;
+	return 1;
+}
+
+static inline void IP_ECN_clear(struct iphdr *iph)
+{
+	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 int IP6_ECN_set_ce(struct ipv6hdr *iph)
+{
+	if (INET_ECN_is_not_ect(ipv6_get_dsfield(iph)))
+		return 0;
+	*(__be32*)iph |= htonl(INET_ECN_CE << 20);
+	return 1;
+}
+
+static inline void IP6_ECN_clear(struct ipv6hdr *iph)
+{
+	*(__be32*)iph &= ~htonl(INET_ECN_MASK << 20);
+}
+
+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