[net-next-2.6.git] / include / net / inet_ecn.h

#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) |= __constant_htons(INET_ECN_ECT_0 << 4);	\
    } while (0)

static inline int IP_ECN_set_ce(struct iphdr *iph)
{
	u32 check = 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 += htons(0xFFFB) + htons(ecn);

	iph->check = 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;
	*(u32*)iph |= htonl(INET_ECN_CE << 20);
	return 1;
}

static inline void IP6_ECN_clear(struct ipv6hdr *iph)
{
	*(u32*)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
Commit	Line	Data
1da177e4 LT	1	#ifndef _INET_ECN_H_
	2	#define _INET_ECN_H_
	3
	4	#include <linux/ip.h>
2566a509	5	#include <linux/skbuff.h>
14c85021 ACM	6
14c85021 ACM	7	#include <net/inet_sock.h>
1da177e4 LT	8	#include <net/dsfield.h>
	9
	10	enum {
	11	INET_ECN_NOT_ECT = 0,
	12	INET_ECN_ECT_1 = 1,
	13	INET_ECN_ECT_0 = 2,
	14	INET_ECN_CE = 3,
	15	INET_ECN_MASK = 3,
	16	};
	17
	18	static inline int INET_ECN_is_ce(__u8 dsfield)
	19	{
	20	return (dsfield & INET_ECN_MASK) == INET_ECN_CE;
	21	}
	22
	23	static inline int INET_ECN_is_not_ect(__u8 dsfield)
	24	{
	25	return (dsfield & INET_ECN_MASK) == INET_ECN_NOT_ECT;
	26	}
	27
	28	static inline int INET_ECN_is_capable(__u8 dsfield)
	29	{
	30	return (dsfield & INET_ECN_ECT_0);
	31	}
	32
	33	static inline __u8 INET_ECN_encapsulate(__u8 outer, __u8 inner)
	34	{
	35	outer &= ~INET_ECN_MASK;
	36	outer \|= !INET_ECN_is_ce(inner) ? (inner & INET_ECN_MASK) :
	37	INET_ECN_ECT_0;
	38	return outer;
	39	}
	40
	41	#define INET_ECN_xmit(sk) do { inet_sk(sk)->tos \|= INET_ECN_ECT_0; } while (0)
	42	#define INET_ECN_dontxmit(sk) \
	43	do { inet_sk(sk)->tos &= ~INET_ECN_MASK; } while (0)
	44
	45	#define IP6_ECN_flow_init(label) do { \
	46	(label) &= ~htonl(INET_ECN_MASK << 20); \
	47	} while (0)
	48
	49	#define IP6_ECN_flow_xmit(sk, label) do { \
	50	if (INET_ECN_is_capable(inet_sk(sk)->tos)) \
	51	(label) \|= __constant_htons(INET_ECN_ECT_0 << 4); \
	52	} while (0)
	53
2566a509	54	static inline int IP_ECN_set_ce(struct iphdr *iph)
1da177e4 LT	55	{
	56	u32 check = iph->check;
	57	u32 ecn = (iph->tos + 1) & INET_ECN_MASK;
	58
	59	/*
	60	* After the last operation we have (in binary):
	61	* INET_ECN_NOT_ECT => 01
	62	* INET_ECN_ECT_1 => 10
	63	* INET_ECN_ECT_0 => 11
	64	* INET_ECN_CE => 00
	65	*/
	66	if (!(ecn & 2))
2566a509	67	return !ecn;
1da177e4 LT	68
	69	/*
	70	* The following gives us:
	71	* INET_ECN_ECT_1 => check += htons(0xFFFD)
	72	* INET_ECN_ECT_0 => check += htons(0xFFFE)
	73	*/
	74	check += htons(0xFFFB) + htons(ecn);
	75
	76	iph->check = check + (check>=0xFFFF);
	77	iph->tos \|= INET_ECN_CE;
2566a509	78	return 1;
1da177e4 LT	79	}
	80
	81	static inline void IP_ECN_clear(struct iphdr *iph)
	82	{
	83	iph->tos &= ~INET_ECN_MASK;
	84	}
	85
	86	static inline void ipv4_copy_dscp(struct iphdr outer, struct iphdr inner)
	87	{
	88	u32 dscp = ipv4_get_dsfield(outer) & ~INET_ECN_MASK;
	89	ipv4_change_dsfield(inner, INET_ECN_MASK, dscp);
	90	}
	91
	92	struct ipv6hdr;
	93
2566a509	94	static inline int IP6_ECN_set_ce(struct ipv6hdr *iph)
1da177e4 LT	95	{
1da177e4 LT	96	if (INET_ECN_is_not_ect(ipv6_get_dsfield(iph)))
2566a509	97	return 0;
1da177e4	98	(u32)iph \|= htonl(INET_ECN_CE << 20);
2566a509	99	return 1;
1da177e4 LT	100	}
	101
	102	static inline void IP6_ECN_clear(struct ipv6hdr *iph)
	103	{
	104	(u32)iph &= ~htonl(INET_ECN_MASK << 20);
	105	}
	106
	107	static inline void ipv6_copy_dscp(struct ipv6hdr outer, struct ipv6hdr inner)
	108	{
	109	u32 dscp = ipv6_get_dsfield(outer) & ~INET_ECN_MASK;
	110	ipv6_change_dsfield(inner, INET_ECN_MASK, dscp);
	111	}
	112
2566a509 TG	113	static inline int INET_ECN_set_ce(struct sk_buff *skb)
	114	{
	115	switch (skb->protocol) {
	116	case __constant_htons(ETH_P_IP):
	117	if (skb->nh.raw + sizeof(struct iphdr) <= skb->tail)
	118	return IP_ECN_set_ce(skb->nh.iph);
	119	break;
	120
	121	case __constant_htons(ETH_P_IPV6):
	122	if (skb->nh.raw + sizeof(struct ipv6hdr) <= skb->tail)
	123	return IP6_ECN_set_ce(skb->nh.ipv6h);
	124	break;
	125	}
	126
	127	return 0;
	128	}
	129
1da177e4	130	#endif