decomp/schemes/rfc4996.c File Reference

Library of decoding methods from RFC4997 and RFC4996. More...

#include "rfc4996.h"
#include "rohc_bit_ops.h"
#include "rohc_traces_internal.h"
#include "rohc_decomp_internals.h"
#include "rohc_debug.h"
#include "rohc_utils.h"
#include "crc.h"
#include "protocols/tcp.h"
#include "rohc_packets.h"
#include "rohc_decomp.h"
#include <string.h>
#include <assert.h>

Include dependency graph for decomp/schemes/rfc4996.c:

Functions
int	d_static_or_irreg8 (const uint8_t *const rohc_data, const size_t rohc_len, const int indicator, struct rohc_lsb_field8 *const lsb)
	Decompress the 8-bit given value, according to the indicator. More...
int	d_static_or_irreg16 (const uint8_t *const rohc_data, const size_t rohc_len, const int indicator, struct rohc_lsb_field16 *const lsb)
	Decompress the 16-bit given value, according to the indicator. More...
int	d_static_or_irreg32 (const uint8_t *const rohc_data, const size_t rohc_len, const int indicator, struct rohc_lsb_field32 *const lsb)
	Decompress the 32-bit given value, according to the indicator. More...
int	variable_length_32_dec (const uint8_t *const rohc_data, const size_t rohc_len, const int indicator, struct rohc_lsb_field32 *const lsb)
	Decode the 32 bits value, according to the indicator. More...
unsigned int	rsf_index_dec (const unsigned int rsf_index)
	Calculate the rsf flags from the rsf index. More...
bool	d_ip_id_lsb (const struct rohc_decomp_ctxt *const context, const struct rohc_lsb_decode *const ip_id_lsb_ctxt, const uint16_t msn, const uint32_t ip_id_bits, const size_t ip_id_bits_nr, const rohc_lsb_shift_t p, uint16_t *const ip_id)
	Decompress the lower bits of IP-ID. More...
int	d_optional_ip_id_lsb (const struct rohc_decomp_ctxt *const context, const uint8_t *const rohc_data, const size_t data_len, const int behavior, const int indicator, struct rohc_lsb_field16 *const lsb)
	Decompress the IP-ID. More...

Detailed Description

Library of decoding methods from RFC4997 and RFC4996.

Author

FWX rohc_.nosp@m.team.nosp@m.@dial.nosp@m.ine..nosp@m.fr

Didier Barvaux didie.nosp@m.r@ba.nosp@m.rvaux.nosp@m..org

Function Documentation

d_ip_id_lsb()

bool d_ip_id_lsb	(	const struct rohc_decomp_ctxt *const	context,
		const struct rohc_lsb_decode *const	ip_id_lsb_ctxt,
		const uint16_t	msn,
		const uint32_t	ip_id_bits,
		const size_t	ip_id_bits_nr,
		const rohc_lsb_shift_t	p,
		uint16_t *const	ip_id
	)

Decompress the lower bits of IP-ID.

See RFC4996 page 75

Parameters

	context	The decompression context
	ip_id_lsb_ctxt	The LSB decoding context for the IP-ID offset
	msn	The Master Sequence Number
	ip_id_bits	The received IP-ID offset bits to decode
	ip_id_bits_nr	The number of received IP-ID offset bits to decode
	p	The offset parameter p to use for LSB decoding
[out]	ip_id	The decoded IP-ID value

Returns

true if IP-ID was successfully decoded, false if decoding failed

Todo:

TODO: could be merged with decomp/schemes/ip_id_offset.[ch] module

d_optional_ip_id_lsb()

int d_optional_ip_id_lsb	(	const struct rohc_decomp_ctxt *const	context,
		const uint8_t *const	rohc_data,
		const size_t	data_len,
		const int	behavior,
		const int	indicator,
		struct rohc_lsb_field16 *const	lsb
	)

Decompress the IP-ID.

See RFC4996 page 76

Parameters

	context	The decompression context
	rohc_data	The ROHC data to parse
	data_len	The length of the ROHC data to parse (in bytes)
	behavior	The IP-ID behavior
	indicator	The compression indicator
[out]	lsb	The LSB bits extracted from the ROHC packet

Returns

The length (in bytes) of the compressed value, -1 if ROHC data is malformed

d_static_or_irreg16()

int d_static_or_irreg16	(	const uint8_t *const	rohc_data,
		const size_t	rohc_len,
		const int	indicator,
		struct rohc_lsb_field16 *const	lsb
	)

Decompress the 16-bit given value, according to the indicator.

Parameters

	rohc_data	The ROHC data to parse
	rohc_len	The length of the ROHC data to parse (in bytes)
	indicator	The indicator of compression
[out]	lsb	The LSB bits extracted from the ROHC packet

Returns

The length (in bytes) of the compressed value, -1 if ROHC data is malformed

d_static_or_irreg32()

int d_static_or_irreg32	(	const uint8_t *const	rohc_data,
		const size_t	rohc_len,
		const int	indicator,
		struct rohc_lsb_field32 *const	lsb
	)

Decompress the 32-bit given value, according to the indicator.

Parameters

	rohc_data	The ROHC data to parse
	rohc_len	The length of the ROHC data to parse (in bytes)
	indicator	The indicator of compression
[out]	lsb	The LSB bits extracted from the ROHC packet

Returns

The length (in bytes) of the compressed value, -1 if ROHC data is malformed

d_static_or_irreg8()

int d_static_or_irreg8	(	const uint8_t *const	rohc_data,
		const size_t	rohc_len,
		const int	indicator,
		struct rohc_lsb_field8 *const	lsb
	)

Decompress the 8-bit given value, according to the indicator.

Parameters

	rohc_data	The ROHC data to parse
	rohc_len	The length of the ROHC data to parse (in bytes)
	indicator	The indicator of compression
[out]	lsb	The LSB bits extracted from the ROHC packet

Returns

The length (in bytes) of the compressed value, -1 if ROHC data is malformed

rsf_index_dec()

unsigned int rsf_index_dec

(

const unsigned int

rsf_index

)

Calculate the rsf flags from the rsf index.

See RFC4996 page 71

Parameters

rsf_index

The rsf index

Returns

The rsf flags

variable_length_32_dec()

int variable_length_32_dec	(	const uint8_t *const	rohc_data,
		const size_t	rohc_len,
		const int	indicator,
		struct rohc_lsb_field32 *const	lsb
	)

Decode the 32 bits value, according to the indicator.

See RFC4996 page 46

Parameters

	rohc_data	The ROHC data to parse
	rohc_len	The length of the ROHC data to parse (in bytes)
	indicator	The indicator of compression
[out]	lsb	The LSB bits extracted from the ROHC packet

Returns

The length (in bytes) of the compressed value, -1 if ROHC data is malformed