rohc_comp.c File Reference

ROHC compression routines. More...

#include "rohc_comp.h"
#include "rohc_comp_internals.h"
#include "rohc_packets.h"
#include "rohc_traces.h"
#include "rohc_traces_internal.h"
#include "rohc_time_internal.h"
#include "rohc_debug.h"
#include "rohc_utils.h"
#include "sdvl.h"
#include "rohc_add_cid.h"
#include "rohc_bit_ops.h"
#include "ip.h"
#include "crc.h"
#include "protocols/udp.h"
#include "protocols/ip_numbers.h"
#include "feedback_parse.h"
#include "config.h"
#include <string.h>
#include <stdlib.h>
#include <stdbool.h>
#include <assert.h>
#include <stdarg.h>

Include dependency graph for rohc_comp.c:

Functions
static struct rohc_comp_profile *	rohc_get_profile_from_id (const struct rohc_comp *comp, const rohc_profile_t profile_id)
	Find out a ROHC profile given a profile ID.
static struct rohc_comp_profile *	c_get_profile_from_packet (const struct rohc_comp const comp, const struct net_pkt const packet)
	Find out a ROHC profile given an IP protocol ID.
static bool	c_create_contexts (struct rohc_comp *const comp)
	Create the array of compression contexts.
static void	c_destroy_contexts (struct rohc_comp *const comp)
	Destroy all the compression contexts in the context array.
static struct rohc_comp_ctxt *	c_create_context (struct rohc_comp const comp, const struct rohc_comp_profile const profile, const struct net_pkt *const packet, const struct rohc_ts arrival_time)
	Create a compression context.
static struct rohc_comp_ctxt *	rohc_comp_find_ctxt (struct rohc_comp const comp, const struct net_pkt const packet, const int profile_id_hint, const struct rohc_ts arrival_time)
	Find a compression context given an IP packet.
static struct rohc_comp_ctxt *	c_get_context (struct rohc_comp *const comp, const rohc_cid_t cid)
	Find out a context given its CID.
static bool	__rohc_comp_deliver_feedback (struct rohc_comp const comp, const uint8_t const packet, const size_t size)
	Deliver a feedback packet to the compressor.
static bool	rohc_comp_feedback_parse_cid (const struct rohc_comp const comp, const uint8_t const feedback, const size_t feedback_len, rohc_cid_t const cid, size_t const cid_len)
	Parse ROHC feedback CID.
static bool	rohc_comp_feedback_parse_opt_sn (const struct rohc_comp_ctxt const context, const uint8_t const feedback_data, const size_t feedback_data_len, uint32_t const sn_bits, size_t const sn_bits_nr)
	Parse the FEEDBACK-2 SN option.
static bool	rohc_comp_feedback_check_opts (const struct rohc_comp_ctxt *const context, const size_t opts_present[ROHC_FEEDBACK_OPT_MAX])
	Check FEEDBACK-2 options.
struct rohc_comp *	rohc_comp_new2 (const rohc_cid_type_t cid_type, const rohc_cid_t max_cid, const rohc_comp_random_cb_t rand_cb, void *const rand_priv)
	Create a new ROHC compressor.
void	rohc_comp_free (struct rohc_comp *const comp)
	Destroy the given ROHC compressor.
bool	rohc_comp_set_traces_cb2 (struct rohc_comp const comp, rohc_trace_callback2_t callback, void const priv_ctxt)
	Set the callback function used to manage traces in compressor.
rohc_status_t	rohc_compress4 (struct rohc_comp const comp, const struct rohc_buf uncomp_packet, struct rohc_buf const rohc_packet)
	Compress the given uncompressed packet into a ROHC packet.
rohc_status_t	rohc_comp_get_segment2 (struct rohc_comp const comp, struct rohc_buf const segment)
	Get the next ROHC segment if any.
bool	rohc_comp_force_contexts_reinit (struct rohc_comp *const comp)
	Force the compressor to re-initialize all its contexts.
bool	rohc_comp_set_wlsb_window_width (struct rohc_comp *const comp, const size_t width)
	Set the window width for the W-LSB encoding scheme.
bool	rohc_comp_set_periodic_refreshes (struct rohc_comp *const comp, const size_t ir_timeout, const size_t fo_timeout)
	Set the timeout values for IR and FO periodic refreshes.
bool	rohc_comp_set_list_trans_nr (struct rohc_comp *const comp, const size_t list_trans_nr)
	Set the number of uncompressed transmissions for list compression.
bool	rohc_comp_set_rtp_detection_cb (struct rohc_comp const comp, rohc_rtp_detection_callback_t callback, void const rtp_private)
	Set the RTP detection callback function.
bool	rohc_comp_profile_enabled (const struct rohc_comp *const comp, const rohc_profile_t profile)
	Is the given compression profile enabled for a compressor?
bool	rohc_comp_enable_profile (struct rohc_comp *const comp, const rohc_profile_t profile)
	Enable a compression profile for a compressor.
bool	rohc_comp_disable_profile (struct rohc_comp *const comp, const rohc_profile_t profile)
	Disable a compression profile for a compressor.
bool	rohc_comp_enable_profiles (struct rohc_comp *const comp,...)
	Enable several compression profiles for a compressor.
bool	rohc_comp_disable_profiles (struct rohc_comp *const comp,...)
	Disable several compression profiles for a compressor.
bool	rohc_comp_set_mrru (struct rohc_comp *const comp, const size_t mrru)
	Set the Maximum Reconstructed Reception Unit (MRRU).
bool	rohc_comp_get_mrru (const struct rohc_comp const comp, size_t const mrru)
	Get the Maximum Reconstructed Reception Unit (MRRU).
bool	rohc_comp_get_max_cid (const struct rohc_comp const comp, size_t const max_cid)
	Get the maximal CID value the compressor uses.
bool	rohc_comp_get_cid_type (const struct rohc_comp const comp, rohc_cid_type_t const cid_type)
	Get the CID type that the compressor uses.
bool	rohc_comp_set_features (struct rohc_comp *const comp, const rohc_comp_features_t features)
	Enable/disable features for ROHC compressor.
bool	rohc_comp_deliver_feedback2 (struct rohc_comp *const comp, const struct rohc_buf feedback)
	Deliver a feedback packet to the compressor.
bool	rohc_comp_get_last_packet_info2 (const struct rohc_comp const comp, rohc_comp_last_packet_info2_t const info)
	Get some information about the last compressed packet.
bool	rohc_comp_get_general_info (const struct rohc_comp const comp, rohc_comp_general_info_t const info)
	Get some general information about the compressor.
const char *	rohc_comp_get_state_descr (const rohc_comp_state_t state)
	Give a description for the given ROHC compression context state.
void	rohc_comp_change_mode (struct rohc_comp_ctxt *const context, const rohc_mode_t new_mode)
	Change the mode of the context.
void	rohc_comp_change_state (struct rohc_comp_ctxt *const context, const rohc_comp_state_t new_state)
	Change the state of the context.
void	rohc_comp_periodic_down_transition (struct rohc_comp_ctxt *const context)
	Periodically change the context state after a certain number of packets.
bool	rohc_comp_reinit_context (struct rohc_comp_ctxt *const context)
	Re-initialize the given context.
bool	rohc_comp_feedback_parse_opts (const struct rohc_comp_ctxt const context, const uint8_t const packet, const size_t packet_len, const uint8_t const feedback_data, const size_t feedback_data_len, size_t opts_present[ROHC_FEEDBACK_OPT_MAX], uint32_t const sn_bits, size_t *const sn_bits_nr, uint8_t crc_in_packet, size_t crc_pos_from_end)
	Parse FEEDBACK-2 options.
Variables
struct rohc_comp_profile c_rtp_profile c_udp_profile c_udp_lite_profile c_esp_profile c_tcp_profile c_ip_profile	c_uncompressed_profile
	Define the compression part of the Uncompressed profile as described in the RFC 3095.
static struct rohc_comp_profile *const	rohc_comp_profiles [C_NUM_PROFILES]
	The compression parts of the ROHC profiles.

Detailed Description

ROHC compression routines.

Author:: Didier Barvaux <didier.barvaux@toulouse.viveris.com>; Didier Barvaux <didier@barvaux.org>; David Moreau from TAS

Function Documentation

static bool __rohc_comp_deliver_feedback	(	struct rohc_comp *const	comp,
		const uint8_t *const	packet,
		const size_t	size
	)			`[static]`

Deliver a feedback packet to the compressor.

When feedback is received by the decompressor, this function is called and delivers the feedback to the right profile/context of the compressor.

Parameters:

	comp	The ROHC compressor
	packet	The feedback data
	size	The length of the feedback packet

Returns:: true if the feedback was successfully taken into account, false if the feedback could not be taken into account

static struct rohc_comp_ctxt * c_create_context	(	struct rohc_comp *const	comp,
		const struct rohc_comp_profile *const	profile,
		const struct net_pkt *const	packet,
		const struct rohc_ts	arrival_time
	)			`[static, read]`

Create a compression context.

Parameters:

	comp	The ROHC compressor
	profile	The profile to associate the context with
	packet	The packet to create a compression context for
	arrival_time	The time at which packet was received (0 if unknown, or to disable time-related features in ROHC protocol)

Returns:: The compression context if successful, NULL otherwise

static bool c_create_contexts ( struct rohc_comp *const comp ) [static]

Create the array of compression contexts.

Parameters:

comp

The ROHC compressor

Returns:: true if the creation is successful, false otherwise

static void c_destroy_contexts ( struct rohc_comp *const comp ) [static]

Destroy all the compression contexts in the context array.

The profile-specific contexts are also destroyed.

Parameters:

comp

The ROHC compressor

static struct rohc_comp_ctxt * c_get_context	(	struct rohc_comp *const	comp,
		const rohc_cid_t	cid
	)			`[static, read]`

Find out a context given its CID.

Parameters:

	comp	The ROHC compressor
	cid	The CID of the context to find

Returns:: The context with the given CID if found, NULL otherwise

static struct rohc_comp_profile * c_get_profile_from_packet	(	const struct rohc_comp *const	comp,
		const struct net_pkt *const	packet
	)			`[static, read]`

Find out a ROHC profile given an IP protocol ID.

Parameters:

	comp	The ROHC compressor
	packet	The packet to find a compression profile for

Returns:: The ROHC profile if found, NULL otherwise

void rohc_comp_change_mode	(	struct rohc_comp_ctxt *const	context,
		const rohc_mode_t	new_mode
	)

Change the mode of the context.

Parameters:

	context	The compression context
	new_mode	The new mode the context must enter in

void rohc_comp_change_state	(	struct rohc_comp_ctxt *const	context,
		const rohc_comp_state_t	new_state
	)

Change the state of the context.

Parameters:

	context	The compression context
	new_state	The new state the context must enter in

static bool rohc_comp_feedback_check_opts	(	const struct rohc_comp_ctxt *const	context,
		const size_t	opts_present[ROHC_FEEDBACK_OPT_MAX]
	)			`[static]`

Check FEEDBACK-2 options.

sanity checks:

some profiles do not support all options
some options cannot be specified multiple times
some options cannot be specified without CRC

Parameters:

	context	The ROHC decompression context
	opts_present	Whether options are present or not

Returns:: true if feedback options are valid, false if feedback options are not valid

static bool rohc_comp_feedback_parse_cid	(	const struct rohc_comp *const	comp,
		const uint8_t *const	feedback,
		const size_t	feedback_len,
		rohc_cid_t *const	cid,
		size_t *const	cid_len
	)			`[static]`

Parse ROHC feedback CID.

Parameters:

	comp	The ROHC compressor
	feedback	The ROHC feedback data to parse
	feedback_len	The length of the ROHC feedback data
`[out]`	cid	The CID of the ROHC feedback
`[out]`	cid_len	The length of the CID of the ROHC feedback

Returns:: true if feedback CID was successfully parsed, false if feedback CID is malformed

static bool rohc_comp_feedback_parse_opt_sn	(	const struct rohc_comp_ctxt *const	context,
		const uint8_t *const	feedback_data,
		const size_t	feedback_data_len,
		uint32_t *const	sn_bits,
		size_t *const	sn_bits_nr
	)			`[static]`

Parse the FEEDBACK-2 SN option.

Parameters:

	context	The ROHC decompression context
	feedback_data	The feedback data without the CID bits
	feedback_data_len	The length of the feedback data without the CID bits
`[out]`	sn_bits	in: the SN bits collected in base header out: the SN bits collected in base header and options
`[out]`	sn_bits_nr	in: the number of SN bits collected in base header out: the number of SN bits collected in base header and options

Returns:: true if feedback options were successfully parsed, false if feedback options were malformed or CRC is wrong

bool rohc_comp_feedback_parse_opts	(	const struct rohc_comp_ctxt *const	context,
		const uint8_t *const	packet,
		const size_t	packet_len,
		const uint8_t *const	feedback_data,
		const size_t	feedback_data_len,
		size_t	opts_present[ROHC_FEEDBACK_OPT_MAX],
		uint32_t *const	sn_bits,
		size_t *const	sn_bits_nr,
		uint8_t	crc_in_packet,
		size_t	crc_pos_from_end
	)

Parse FEEDBACK-2 options.

Parameters:

	context	The ROHC decompression context
	packet	The whole feedback packet with CID bits
	packet_len	The length of the whole feedback packet with CID bits
	feedback_data	The feedback data without the CID bits
	feedback_data_len	The length of the feedback data without the CID bits
`[out]`	opts_present	Whether options are present or not
`[out]`	sn_bits	in: the SN bits collected in base header out: the SN bits collected in base header and options
`[out]`	sn_bits_nr	in: the number of SN bits collected in base header out: the number of SN bits collected in base header and options
	crc_in_packet	The CRC of the feedback packet
	crc_pos_from_end	The position of the CRC byte from the end of the feedback packet

Returns:: true if feedback options were successfully parsed, false if feedback options were malformed or CRC is wrong

static struct rohc_comp_ctxt * rohc_comp_find_ctxt	(	struct rohc_comp *const	comp,
		const struct net_pkt *const	packet,
		const int	profile_id_hint,
		const struct rohc_ts	arrival_time
	)			`[static, read]`

Find a compression context given an IP packet.

Parameters:

	comp	The ROHC compressor
	packet	The packet to find a compression context for
	profile_id_hint	If positive, indicate the profile to use
	arrival_time	The time at which packet was received (0 if unknown, or to disable time-related features in the ROHC protocol)

Returns:: The context if found or successfully created, NULL if not found

void rohc_comp_periodic_down_transition ( struct rohc_comp_ctxt *const context )

Periodically change the context state after a certain number of packets.

Parameters:

context

The compression context

bool rohc_comp_reinit_context ( struct rohc_comp_ctxt *const context )

Re-initialize the given context.

Make the context restart its initialization with decompressor, ie. it goes in the lowest compression state.

Parameters:

context

The compression context to re-initialize

Returns:: true in case of success, false otherwise

static struct rohc_comp_profile * rohc_get_profile_from_id	(	const struct rohc_comp *	comp,
		const rohc_profile_t	profile_id
	)			`[static, read]`

Find out a ROHC profile given a profile ID.

Parameters:

	comp	The ROHC compressor
	profile_id	The ID of the ROHC profile to find out

Returns:: The ROHC profile if found, NULL otherwise

Variable Documentation

struct rohc_comp_profile c_rtp_profile c_udp_profile c_udp_lite_profile c_esp_profile c_tcp_profile c_ip_profile c_uncompressed_profile

Define the compression part of the Uncompressed profile as described in the RFC 3095.

struct rohc_comp_profile* const rohc_comp_profiles[C_NUM_PROFILES] [static]

Initial value:

{
        &c_rtp_profile,
        &c_udp_profile,  
        &c_udp_lite_profile,
        &c_esp_profile,
        &c_tcp_profile,
        &c_ip_profile,  
        &c_uncompressed_profile, 
}

The compression parts of the ROHC profiles.

The order of profiles declaration is important: they are evaluated in that order. The RTP profile shall be declared before the UDP one for example.

rohc_comp.c File Reference

Functions

Variables

Detailed Description

Function Documentation

Variable Documentation