d_udp_lite.c File Reference

ROHC decompression context for the UDP-Lite profile. More...

#include "d_ip.h"
#include "d_udp.h"
#include "rohc_decomp_rfc3095.h"
#include "rohc_bit_ops.h"
#include "rohc_traces_internal.h"
#include "rohc_debug.h"
#include "rohc_utils.h"
#include "rohc_packets.h"
#include "crc.h"
#include "protocols/udp_lite.h"
#include <string.h>

Include dependency graph for d_udp_lite.c:

Data Structures
struct	d_udp_lite_context
	Define the UDP-Lite part of the decompression profile context. More...
Functions
static bool	d_udp_lite_create (const struct rohc_decomp_ctxt const context, struct rohc_decomp_rfc3095_ctxt const persist_ctxt, struct rohc_decomp_volat_ctxt const volat_ctxt)
	Create the UDP-Lite decompression context.
static void	d_udp_lite_destroy (struct rohc_decomp_rfc3095_ctxt const rfc3095_ctxt, const struct rohc_decomp_volat_ctxt const volat_ctxt)
	Destroy the context.
static rohc_packet_t	udp_lite_detect_packet_type (const struct rohc_decomp_ctxt const context, const uint8_t const rohc_packet, const size_t rohc_length, const size_t large_cid_len)
	Detect the type of ROHC packet for the UDP-Lite profile.
static bool	d_udp_lite_parse (const struct rohc_decomp_ctxt const context, const struct rohc_buf rohc_packet, const size_t large_cid_len, rohc_packet_t const packet_type, struct rohc_decomp_crc const extr_crc, struct rohc_extr_bits const bits, size_t *const rohc_hdr_len)
	Decode one IR, IR-DYN or UO* packet for UDP-Lite profile.
static int	udp_lite_parse_dynamic_udp (const struct rohc_decomp_ctxt const context, const uint8_t packet, const size_t length, struct rohc_extr_bits *const bits)
	Parse the UDP-Lite dynamic part of the ROHC packet.
static int	udp_lite_parse_uo_remainder (const struct rohc_decomp_ctxt const context, const uint8_t packet, unsigned int length, struct rohc_extr_bits *const bits)
	Parse the UDP-Lite remainder of the UO* ROHC packets.
static bool	udp_lite_decode_values_from_bits (const struct rohc_decomp_ctxt context, const struct rohc_extr_bits const bits, struct rohc_decoded_values *const decoded)
	Decode UDP-Lite values from extracted bits.
static int	udp_lite_build_uncomp_udp (const struct rohc_decomp_ctxt const context, const struct rohc_decoded_values const decoded, uint8_t *const dest, const unsigned int payload_len)
	Build an uncompressed UDP-Lite header.
static void	udp_lite_update_context (struct rohc_decomp_ctxt const context, const struct rohc_decoded_values const decoded)
	Update context with decoded UDP-Lite values.
Variables
struct rohc_decomp_profile	d_udplite_profile
	Define the decompression part of the UDP-Lite profile as described in the RFC 4019.

Detailed Description

ROHC decompression context for the UDP-Lite profile.

Author:: Didier Barvaux <didier.barvaux@toulouse.viveris.com>; Didier Barvaux <didier@barvaux.org>

Function Documentation

static bool d_udp_lite_create	(	const struct rohc_decomp_ctxt *const	context,
		struct rohc_decomp_rfc3095_ctxt **const	persist_ctxt,
		struct rohc_decomp_volat_ctxt *const	volat_ctxt
	)			`[static]`

Create the UDP-Lite decompression context.

This function is one of the functions that must exist in one profile for the framework to work.

Parameters:

	context	The main decompression context
`[out]`	persist_ctxt	The persistent part of the decompression context
`[out]`	volat_ctxt	The volatile part of the decompression context

Returns:: true if the UDP-Lite context was successfully created, false if a problem occurred

static void d_udp_lite_destroy	(	struct rohc_decomp_rfc3095_ctxt *const	rfc3095_ctxt,
		const struct rohc_decomp_volat_ctxt *const	volat_ctxt
	)			`[static]`

Destroy the context.

This function is one of the functions that must exist in one profile for the framework to work.

Parameters:

	rfc3095_ctxt	The persistent decompression context for the RFC3095 profiles
	volat_ctxt	The volatile decompression context

static bool d_udp_lite_parse	(	const struct rohc_decomp_ctxt *const	context,
		const struct rohc_buf	rohc_packet,
		const size_t	large_cid_len,
		rohc_packet_t *const	packet_type,
		struct rohc_decomp_crc *const	extr_crc,
		struct rohc_extr_bits *const	bits,
		size_t *const	rohc_hdr_len
	)			`[static]`

Decode one IR, IR-DYN or UO* packet for UDP-Lite profile.

This function is one of the functions that must exist in one profile for the framework to work.

Parameters:

	context	The decompression context
	rohc_packet	The ROHC packet to decode
	large_cid_len	The length of the optional large CID field
`[in,out]`	packet_type	IN: The type of the ROHC packet to parse OUT: The type of the parsed ROHC packet
`[out]`	extr_crc	The CRC bits extracted from the ROHC header
`[out]`	bits	The bits extracted from the ROHC header
`[out]`	rohc_hdr_len	The length of the ROHC header (in bytes)

Returns:: true if packet is successfully parsed, false otherwise

static int udp_lite_build_uncomp_udp	(	const struct rohc_decomp_ctxt *const	context,
		const struct rohc_decoded_values *const	decoded,
		uint8_t *const	dest,
		const unsigned int	payload_len
	)			`[static]`

Build an uncompressed UDP-Lite header.

Todo:: check for dest size before writing into it

Parameters:

	context	The decompression context
	decoded	The values decoded from the ROHC header
	dest	The buffer to store the UDP-Lite header
	payload_len	The length of the UDP-Lite payload

Returns:: The length of the next header (ie. the UDP-Lite header), -1 in case of error

static bool udp_lite_decode_values_from_bits	(	const struct rohc_decomp_ctxt *	context,
		const struct rohc_extr_bits *const	bits,
		struct rohc_decoded_values *const	decoded
	)			`[static]`

Decode UDP-Lite values from extracted bits.

The following values are decoded:

UDP-Lite source port
UDP-Lite destination port
UDP-Lite checksum
UDP-Lite Checksum Coverage (CC)

Parameters:

	context	The decompression context
	bits	The extracted bits
	decoded	OUT: The corresponding decoded values

Returns:: true if decoding is successful, false otherwise

static rohc_packet_t udp_lite_detect_packet_type	(	const struct rohc_decomp_ctxt *const	context,
		const uint8_t *const	rohc_packet,
		const size_t	rohc_length,
		const size_t	large_cid_len
	)			`[static]`

Detect the type of ROHC packet for the UDP-Lite profile.

Parse optional CCE packet type, then normal packet type.

Parameters:

	context	The decompression context
	rohc_packet	The ROHC packet
	rohc_length	The length of the ROHC packet
	large_cid_len	The length of the optional large CID field

Returns:: The packet type

static int udp_lite_parse_dynamic_udp	(	const struct rohc_decomp_ctxt *const	context,
		const uint8_t *	packet,
		const size_t	length,
		struct rohc_extr_bits *const	bits
	)			`[static]`

Parse the UDP-Lite dynamic part of the ROHC packet.

Parameters:

	context	The decompression context
	packet	The ROHC packet to parse
	length	The length of the ROHC packet
	bits	OUT: The bits extracted from the ROHC header

Returns:: The number of bytes read in the ROHC packet, -1 in case of failure

static int udp_lite_parse_uo_remainder	(	const struct rohc_decomp_ctxt *const	context,
		const uint8_t *	packet,
		unsigned int	length,
		struct rohc_extr_bits *const	bits
	)			`[static]`

Parse the UDP-Lite remainder of the UO* ROHC packets.

Parameters:

	context	The decompression context
	packet	The ROHC packet to parse
	length	The length of the ROHC packet
	bits	OUT: The bits extracted from the ROHC header

Returns:: The number of bytes read in the ROHC packet, -1 in case of failure

static void udp_lite_update_context	(	struct rohc_decomp_ctxt *const	context,
		const struct rohc_decoded_values *const	decoded
	)			`[static]`

Update context with decoded UDP-Lite values.

The following decoded values are updated in context:

UDP-Lite source port
UDP-Lite destination port

Parameters:

	context	The decompression context
	decoded	The decoded values to update in the context

Variable Documentation

struct rohc_decomp_profile d_udplite_profile

Initial value:

{
        .id              = ROHC_PROFILE_UDPLITE, 
        .msn_max_bits    = 16,
        .new_context     = (rohc_decomp_new_context_t) d_udp_lite_create,
        .free_context    = (rohc_decomp_free_context_t) d_udp_lite_destroy,
        .detect_pkt_type = udp_lite_detect_packet_type,
        .parse_pkt       = (rohc_decomp_parse_pkt_t) d_udp_lite_parse,
        .decode_bits     = (rohc_decomp_decode_bits_t) rfc3095_decomp_decode_bits,
        .build_hdrs      = (rohc_decomp_build_hdrs_t) rfc3095_decomp_build_hdrs,
        .update_ctxt     = (rohc_decomp_update_ctxt_t) rfc3095_decomp_update_ctxt,
        .attempt_repair  = (rohc_decomp_attempt_repair_t) rfc3095_decomp_attempt_repair,
        .get_sn          = rohc_decomp_rfc3095_get_sn,
}

Define the decompression part of the UDP-Lite profile as described in the RFC 4019.

d_udp_lite.c File Reference

Data Structures

Functions

Variables

Detailed Description

Function Documentation

Variable Documentation