rohc_decomp_rfc3095.h File Reference

#include "rohc_decomp.h"
#include "rohc_decomp_internals.h"
#include "rohc_packets.h"
#include "rohc_utils.h"
#include "schemes/decomp_wlsb.h"
#include "schemes/ip_id_offset.h"
#include "schemes/decomp_list.h"
#include "protocols/udp_lite.h"
#include "ip.h"
#include "crc.h"
#include <stddef.h>
#include <stdbool.h>

Include dependency graph for rohc_decomp_rfc3095.h:

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Go to the source code of this file.

Data Structures
struct	rohc_extr_ip_bits
struct	rohc_extr_bits
	The bits extracted from ROHC UO* base headers. More...
struct	rohc_decoded_ip_values
struct	rohc_decoded_values
	The values decoded from the bits extracted from ROHC header. More...
struct	rohc_decomp_rfc3095_changes
	Store information about an IP header between the different decompressions of IP packets. More...
struct	rohc_decomp_rfc3095_ctxt
	The generic decompression context for RFC3095-based profiles. More...
Functions
bool	rohc_decomp_rfc3095_create (const struct rohc_decomp_ctxt *const context, struct rohc_decomp_rfc3095_ctxt **const persist_ctxt, struct rohc_decomp_volat_ctxt *const volat_ctxt, rohc_trace_callback2_t trace_cb, void *const trace_cb_priv, const int profile_id)
	Create the RFC3095 volatile and persistent parts of the context.
void	rohc_decomp_rfc3095_destroy (struct rohc_decomp_rfc3095_ctxt *const rfc3095_ctxt, const struct rohc_decomp_volat_ctxt *const volat_ctxt)
	Destroy the context.
bool	rfc3095_decomp_parse_pkt (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)
	Parse one IR, IR-DYN, UO-0, UO-1*, or UOR-2* packet.
rohc_status_t	rfc3095_decomp_build_hdrs (const struct rohc_decomp *const decomp, const struct rohc_decomp_ctxt *const context, const rohc_packet_t packet_type, const struct rohc_decomp_crc *const extr_crc, const struct rohc_decoded_values *const decoded, const size_t payload_len, struct rohc_buf *const uncomp_hdrs, size_t *const uncomp_hdrs_len)
	Build the uncompressed headers.
bool	rfc3095_decomp_decode_bits (const struct rohc_decomp_ctxt *const context, const struct rohc_extr_bits *const bits, const size_t payload_len, struct rohc_decoded_values *const decoded)
	Decode values from extracted bits.
void	rfc3095_decomp_update_ctxt (struct rohc_decomp_ctxt *const context, const struct rohc_decoded_values *const decoded, const size_t payload_len, bool *const do_change_mode)
	Update context with decoded values.
bool	rfc3095_decomp_attempt_repair (const struct rohc_decomp *const decomp, const struct rohc_decomp_ctxt *const context, const struct rohc_ts pkt_arrival_time, struct rohc_decomp_crc_corr_ctxt *const crc_corr, struct rohc_extr_bits *const extr_bits)
	Attempt a packet/context repair upon CRC failure.
uint32_t	rohc_decomp_rfc3095_get_sn (const struct rohc_decomp_ctxt *const context)
	Get the reference SN value of the context.
static bool	is_ipv4_pkt (const struct rohc_extr_ip_bits *const bits)
	Is the given IP header IPV4 wrt packet?
static bool	is_ipv4_rnd_pkt (const struct rohc_extr_ip_bits *const bits)
	Is the given IP header IPv4 and its IP-ID random wrt packet?
static bool	is_ipv4_non_rnd_pkt (const struct rohc_extr_ip_bits *const bits)
	Is the given IP header IPv4 and its IP-ID non-random wrt packet?

---

Function Documentation

static bool is_ipv4_non_rnd_pkt

(

const struct rohc_extr_ip_bits *const

bits

)

[inline, static]

Is the given IP header IPv4 and its IP-ID non-random wrt packet?

Parameters:

bits

The bits extracted from packet

Returns:

true if IPv4 and non-random, false otherwise

static bool is_ipv4_pkt

(

const struct rohc_extr_ip_bits *const

bits

)

[inline, static]

Is the given IP header IPV4 wrt packet?

Parameters:

bits

The bits extracted from packet

Returns:

true if IPv4, false if IPv6

static bool is_ipv4_rnd_pkt

(

const struct rohc_extr_ip_bits *const

bits

)

[inline, static]

Is the given IP header IPv4 and its IP-ID random wrt packet?

Parameters:

bits

The bits extracted from packet

Returns:

true if IPv4 and random, false otherwise

bool rfc3095_decomp_attempt_repair	(	const struct rohc_decomp *const	decomp,
		const struct rohc_decomp_ctxt *const	context,
		const struct rohc_ts	pkt_arrival_time,
		struct rohc_decomp_crc_corr_ctxt *const	crc_corr,
		struct rohc_extr_bits *const	extr_bits
	)

Attempt a packet/context repair upon CRC failure.

Parameters:

	decomp	The ROHC decompressor
	context	The decompression context
	pkt_arrival_time	The arrival time of the ROHC packet that caused the CRC failure
[in,out]	crc_corr	The context for corrections upon CRC failures
[in,out]	extr_bits	The bits extracted from the ROHC header

Returns:

true if repair is possible, false if not

rohc_status_t rfc3095_decomp_build_hdrs	(	const struct rohc_decomp *const	decomp,
		const struct rohc_decomp_ctxt *const	context,
		const rohc_packet_t	packet_type,
		const struct rohc_decomp_crc *const	extr_crc,
		const struct rohc_decoded_values *const	decoded,
		const size_t	payload_len,
		struct rohc_buf *const	uncomp_hdrs,
		size_t *const	uncomp_hdrs_len
	)

Build the uncompressed headers.

Todo:

check for uncomp_hdrs size before writing into it

Parameters:

	decomp	The ROHC decompressor
	context	The decompression context
	packet_type	The type of ROHC packet
	extr_crc	The CRC bits extracted from the ROHC header
	decoded	The values decoded from ROHC header
	payload_len	The length of the packet payload
[out]	uncomp_hdrs	The buffer to store the uncompressed headers
[out]	uncomp_hdrs_len	The length of the uncompressed headers written into the buffer

Returns:

Possible values:

• ROHC_STATUS_OK if headers are built successfully,
• ROHC_STATUS_BAD_CRC if headers do not match CRC,
• ROHC_STATUS_OUTPUT_TOO_SMALL if the output buffer is too small

bool rfc3095_decomp_decode_bits	(	const struct rohc_decomp_ctxt *const	context,
		const struct rohc_extr_bits *const	bits,
		const size_t	payload_len,
		struct rohc_decoded_values *const	decoded
	)

Decode values from extracted bits.

The following values are decoded:

• SN
• fields related to the outer IP header
• fields related to the inner IP header (if it exists)

Other fields may be decoded by the profile-specific callback named decode_values_from_bits.

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

Parameters:

	context	The decompression context
	bits	The bits extracted from the ROHC packet
	payload_len	The length of the packet payload (in bytes)
[out]	decoded	The corresponding decoded values

Returns:

true if decoding is successful, false otherwise

bool rfc3095_decomp_parse_pkt	(	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
	)

Parse one IR, IR-DYN, UO-0, UO-1*, or UOR-2* packet.

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

See also:

parse_ir

parse_irdyn

parse_uo0

parse_uo1

parse_uo1rtp

parse_uo1id

parse_uo1ts

parse_uor2

parse_uor2rtp

parse_uor2id

parse_uor2ts

void rfc3095_decomp_update_ctxt	(	struct rohc_decomp_ctxt *const	context,
		const struct rohc_decoded_values *const	decoded,
		const size_t	payload_len,
		bool *const	do_change_mode
	)

Update context with decoded values.

The following decoded values are updated in context:

• SN
• static & dynamic fields of the outer IP header
• static & dynamic fields of the inner IP header (if it exists)
• fields for the next header (optional, depends on profile)

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

Parameters:

	context	The decompression context
	decoded	The decoded values to update in the context
	payload_len	The length of the packet payload
[out]	do_change_mode	Whether the profile context wants to change its operational mode or not

bool rohc_decomp_rfc3095_create	(	const struct rohc_decomp_ctxt *const	context,
		struct rohc_decomp_rfc3095_ctxt **const	persist_ctxt,
		struct rohc_decomp_volat_ctxt *const	volat_ctxt,
		rohc_trace_callback2_t	trace_cb,
		void *const	trace_cb_priv,
		const int	profile_id
	)

Create the RFC3095 volatile and persistent parts of the context.

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

Parameters:

	context	The decompression context
[out]	persist_ctxt	The persistent part of the decompression context
[out]	volat_ctxt	The volatile part of the decompression context
	trace_cb	The function to call for printing traces
	trace_cb_priv	An optional private context, may be NULL
	profile_id	The ID of the associated decompression profile

Returns:

true if the Uncompressed context was successfully created, false if a problem occurred

void rohc_decomp_rfc3095_destroy	(	struct rohc_decomp_rfc3095_ctxt *const	rfc3095_ctxt,
		const struct rohc_decomp_volat_ctxt *const	volat_ctxt
	)

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 generic decompression context
	volat_ctxt	The volatile part of the decompression context

uint32_t rohc_decomp_rfc3095_get_sn

(

const struct rohc_decomp_ctxt *const

context

)

Get the reference SN value of the context.

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

Parameters:

context

The decompression context

Returns:

The reference SN value