[deliverable/linux.git] / net / 6lowpan / nhc.h

#ifndef __6LOWPAN_NHC_H
#define __6LOWPAN_NHC_H

#include <linux/skbuff.h>
#include <linux/rbtree.h>
#include <linux/module.h>

#include <net/6lowpan.h>
#include <net/ipv6.h>

/**
 * LOWPAN_NHC - helper macro to generate nh id fields and lowpan_nhc struct
 *
 * @__nhc: variable name of the lowpan_nhc struct.
 * @_name: const char * of common header compression name.
 * @_nexthdr: ipv6 nexthdr field for the header compression.
 * @_nexthdrlen: ipv6 nexthdr len for the reserved space.
 * @_idsetup: callback to setup id and mask values.
 * @_idlen: len for the next header id and mask, should be always the same.
 * @_uncompress: callback for uncompression call.
 * @_compress: callback for compression call.
 */
#define LOWPAN_NHC(__nhc, _name, _nexthdr,	\
		   _hdrlen, _idsetup, _idlen,	\
		   _uncompress, _compress)	\
static u8 __nhc##_val[_idlen];			\
static u8 __nhc##_mask[_idlen];			\
static struct lowpan_nhc __nhc = {		\
	.name		= _name,		\
	.nexthdr	= _nexthdr,		\
	.nexthdrlen	= _hdrlen,		\
	.id		= __nhc##_val,		\
	.idmask		= __nhc##_mask,		\
	.idlen		= _idlen,		\
	.idsetup	= _idsetup,		\
	.uncompress	= _uncompress,		\
	.compress	= _compress,		\
}

#define module_lowpan_nhc(__nhc)		\
static int __init __nhc##_init(void)		\
{						\
	return lowpan_nhc_add(&(__nhc));	\
}						\
module_init(__nhc##_init);			\
static void __exit __nhc##_exit(void)		\
{						\
	lowpan_nhc_del(&(__nhc));		\
}						\
module_exit(__nhc##_exit);

/**
 * struct lowpan_nhc - hold 6lowpan next hdr compression ifnformation
 *
 * @node: holder for the rbtree.
 * @name: name of the specific next header compression
 * @nexthdr: next header value of the protocol which should be compressed.
 * @nexthdrlen: ipv6 nexthdr len for the reserved space.
 * @id: array for nhc id. Note this need to be in network byteorder.
 * @mask: array for nhc id mask. Note this need to be in network byteorder.
 * @len: the length of the next header id and mask.
 * @setup: callback to setup fill the next header id value and mask.
 * @compress: callback to do the header compression.
 * @uncompress: callback to do the header uncompression.
 */
struct lowpan_nhc {
	struct rb_node	node;
	const char	*name;
	const u8	nexthdr;
	const size_t	nexthdrlen;
	u8		*id;
	u8		*idmask;
	const size_t	idlen;

	void		(*idsetup)(struct lowpan_nhc *nhc);
	int		(*uncompress)(struct sk_buff *skb, size_t needed);
	int		(*compress)(struct sk_buff *skb, u8 **hc_ptr);
};

/**
 * lowpan_nhc_by_nexthdr - return the 6lowpan nhc by ipv6 nexthdr.
 *
 * @nexthdr: ipv6 nexthdr value.
 */
struct lowpan_nhc *lowpan_nhc_by_nexthdr(u8 nexthdr);

/**
 * lowpan_nhc_check_compression - checks if we support compression format. If
 *	we support the nhc by nexthdr field, the 6LoWPAN iphc NHC bit will be
 *	set. If we don't support nexthdr will be added as inline data to the
 *	6LoWPAN header.
 *
 * @skb: skb of 6LoWPAN header to read nhc and replace header.
 * @hdr: ipv6hdr to check the nexthdr value
 * @hc_ptr: pointer for 6LoWPAN header which should increment at the end of
 *	    replaced header.
 * @iphc0: iphc0 pointer to set the 6LoWPAN NHC bit
 */
int lowpan_nhc_check_compression(struct sk_buff *skb,
				 const struct ipv6hdr *hdr, u8 **hc_ptr,
				 u8 *iphc0);

/**
 * lowpan_nhc_do_compression - calling compress callback for nhc
 *
 * @skb: skb of 6LoWPAN header to read nhc and replace header.
 * @hdr: ipv6hdr to set the nexthdr value
 * @hc_ptr: pointer for 6LoWPAN header which should increment at the end of
 *	    replaced header.
 */
int lowpan_nhc_do_compression(struct sk_buff *skb, const struct ipv6hdr *hdr,
			      u8 **hc_ptr);

/**
 * lowpan_nhc_do_uncompression - calling uncompress callback for nhc
 *
 * @nhc: 6LoWPAN nhc context, get by lowpan_nhc_by_ functions.
 * @skb: skb of 6LoWPAN header, skb->data should be pointed to nhc id value.
 * @dev: netdevice for print logging information.
 * @hdr: ipv6hdr for setting nexthdr value.
 */
int lowpan_nhc_do_uncompression(struct sk_buff *skb,
				const struct net_device *dev,
				struct ipv6hdr *hdr);

/**
 * lowpan_nhc_add - register a next header compression to framework
 *
 * @nhc: nhc which should be add.
 */
int lowpan_nhc_add(struct lowpan_nhc *nhc);

/**
 * lowpan_nhc_del - delete a next header compression from framework
 *
 * @nhc: nhc which should be delete.
 */
void lowpan_nhc_del(struct lowpan_nhc *nhc);

/**
 * lowpan_nhc_init - adding all default nhcs
 */
void lowpan_nhc_init(void);

#endif /* __6LOWPAN_NHC_H */
Commit	Line	Data
92aa7c65 AA	1	#ifndef __6LOWPAN_NHC_H
	2	#define __6LOWPAN_NHC_H
	3
	4	#include <linux/skbuff.h>
	5	#include <linux/rbtree.h>
	6	#include <linux/module.h>
	7
	8	#include <net/6lowpan.h>
	9	#include <net/ipv6.h>
	10
92aa7c65 AA	11	/**
	12	* LOWPAN_NHC - helper macro to generate nh id fields and lowpan_nhc struct
	13	*
	14	* @__nhc: variable name of the lowpan_nhc struct.
	15	* @_name: const char * of common header compression name.
	16	* @_nexthdr: ipv6 nexthdr field for the header compression.
	17	* @_nexthdrlen: ipv6 nexthdr len for the reserved space.
	18	* @_idsetup: callback to setup id and mask values.
	19	* @_idlen: len for the next header id and mask, should be always the same.
	20	* @_uncompress: callback for uncompression call.
	21	* @_compress: callback for compression call.
	22	*/
	23	#define LOWPAN_NHC(__nhc, _name, _nexthdr, \
	24	_hdrlen, _idsetup, _idlen, \
	25	_uncompress, _compress) \
	26	static u8 __nhc##_val[_idlen]; \
	27	static u8 __nhc##_mask[_idlen]; \
	28	static struct lowpan_nhc __nhc = { \
	29	.name = _name, \
	30	.nexthdr = _nexthdr, \
	31	.nexthdrlen = _hdrlen, \
	32	.id = __nhc##_val, \
	33	.idmask = __nhc##_mask, \
	34	.idlen = _idlen, \
	35	.idsetup = _idsetup, \
	36	.uncompress = _uncompress, \
	37	.compress = _compress, \
	38	}
	39
	40	#define module_lowpan_nhc(__nhc) \
	41	static int __init __nhc##_init(void) \
	42	{ \
	43	return lowpan_nhc_add(&(__nhc)); \
	44	} \
	45	module_init(__nhc##_init); \
	46	static void __exit __nhc##_exit(void) \
	47	{ \
	48	lowpan_nhc_del(&(__nhc)); \
	49	} \
	50	module_exit(__nhc##_exit);
	51
	52	/**
	53	* struct lowpan_nhc - hold 6lowpan next hdr compression ifnformation
	54	*
	55	* @node: holder for the rbtree.
	56	* @name: name of the specific next header compression
	57	* @nexthdr: next header value of the protocol which should be compressed.
	58	* @nexthdrlen: ipv6 nexthdr len for the reserved space.
	59	* @id: array for nhc id. Note this need to be in network byteorder.
	60	* @mask: array for nhc id mask. Note this need to be in network byteorder.
	61	* @len: the length of the next header id and mask.
	62	* @setup: callback to setup fill the next header id value and mask.
	63	* @compress: callback to do the header compression.
	64	* @uncompress: callback to do the header uncompression.
	65	*/
	66	struct lowpan_nhc {
	67	struct rb_node node;
	68	const char *name;
	69	const u8 nexthdr;
	70	const size_t nexthdrlen;
	71	u8 *id;
	72	u8 *idmask;
	73	const size_t idlen;
	74
75	void (idsetup)(struct lowpan_nhc nhc);
76	int (uncompress)(struct sk_buff skb, size_t needed);
77	int (compress)(struct sk_buff skb, u8 **hc_ptr);
78	};
79
80	/**
81	* lowpan_nhc_by_nexthdr - return the 6lowpan nhc by ipv6 nexthdr.
82	*
83	* @nexthdr: ipv6 nexthdr value.
84	*/
85	struct lowpan_nhc *lowpan_nhc_by_nexthdr(u8 nexthdr);
86
87	/**
88	* lowpan_nhc_check_compression - checks if we support compression format. If
89	* we support the nhc by nexthdr field, the 6LoWPAN iphc NHC bit will be
90	* set. If we don't support nexthdr will be added as inline data to the
91	* 6LoWPAN header.
92	*
93	* @skb: skb of 6LoWPAN header to read nhc and replace header.
94	* @hdr: ipv6hdr to check the nexthdr value
95	* @hc_ptr: pointer for 6LoWPAN header which should increment at the end of
96	* replaced header.
97	* @iphc0: iphc0 pointer to set the 6LoWPAN NHC bit
98	*/
99	int lowpan_nhc_check_compression(struct sk_buff *skb,
100	const struct ipv6hdr hdr, u8 *hc_ptr,
101	u8 *iphc0);
102
103	/**
104	* lowpan_nhc_do_compression - calling compress callback for nhc
105	*
106	* @skb: skb of 6LoWPAN header to read nhc and replace header.
107	* @hdr: ipv6hdr to set the nexthdr value
108	* @hc_ptr: pointer for 6LoWPAN header which should increment at the end of
109	* replaced header.
110	*/
111	int lowpan_nhc_do_compression(struct sk_buff skb, const struct ipv6hdr hdr,
112	u8 **hc_ptr);
113
114	/**
115	* lowpan_nhc_do_uncompression - calling uncompress callback for nhc
116	*
117	* @nhc: 6LoWPAN nhc context, get by lowpan_nhc_by_ functions.
118	* @skb: skb of 6LoWPAN header, skb->data should be pointed to nhc id value.
119	* @dev: netdevice for print logging information.
120	* @hdr: ipv6hdr for setting nexthdr value.
121	*/
8911d774 AA	122	int lowpan_nhc_do_uncompression(struct sk_buff *skb,
8911d774 AA	123	const struct net_device *dev,
92aa7c65 AA	124	struct ipv6hdr *hdr);
	125
	126	/**
	127	* lowpan_nhc_add - register a next header compression to framework
	128	*
	129	* @nhc: nhc which should be add.
	130	*/
	131	int lowpan_nhc_add(struct lowpan_nhc *nhc);
	132
	133	/**
	134	* lowpan_nhc_del - delete a next header compression from framework
	135	*
	136	* @nhc: nhc which should be delete.
	137	*/
	138	void lowpan_nhc_del(struct lowpan_nhc *nhc);
	139
	140	/**
	141	* lowpan_nhc_init - adding all default nhcs
	142	*/
	143	void lowpan_nhc_init(void);
	144
	145	#endif /* __6LOWPAN_NHC_H */