d_ip.c File Reference

ROHC decompression context for the IP-only profile. More...

#include "d_ip.h"
#include "rohc_traces_internal.h"
#include "rohc_bit_ops.h"
#include "rohc_packets.h"
#include "rohc_debug.h"
#include "rohc_utils.h"
#include "rohc_decomp_detect_packet.h"
#include <assert.h>

Include dependency graph for d_ip.c:

Functions
static bool	d_ip_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 IP decompression context.
static void	d_ip_destroy (struct rohc_decomp_rfc3095_ctxt const rfc3095_ctxt, const struct rohc_decomp_volat_ctxt const volat_ctxt)
	Destroy the given IP-only context.
rohc_packet_t	ip_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 IP-based non-RTP profiles.
int	ip_parse_dynamic_ip (const struct rohc_decomp_ctxt const context, const uint8_t packet, const size_t length, struct rohc_extr_bits *const bits)
	Parse the IP dynamic part of the ROHC packet.
int	ip_parse_ext3 (const struct rohc_decomp_ctxt const context, const uint8_t const rohc_data, const size_t rohc_data_len, const rohc_packet_t packet_type, struct rohc_extr_bits *const bits)
	Parse the extension 3 of the UOR-2 packet.
int	parse_inner_header_flags (const struct rohc_decomp_ctxt const context, const uint8_t const flags, const uint8_t fields, const size_t length, struct rohc_extr_ip_bits const bits)
	Parse the inner IP header flags and fields.
int	parse_outer_header_flags (const struct rohc_decomp_ctxt const context, const uint8_t const flags, const uint8_t fields, const size_t length, struct rohc_extr_ip_bits const bits)
	Parse the outer IP header flags and fields.
Variables
struct rohc_decomp_profile	d_ip_profile
	Define the decompression part of the IP-only profile as described in the RFC 3843.

Detailed Description

ROHC decompression context for the IP-only profile.

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

Function Documentation

static bool d_ip_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 IP decompression 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

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

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

Destroy the given IP-only 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

rohc_packet_t ip_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 IP-based non-RTP profiles.

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

int ip_parse_dynamic_ip	(	const struct rohc_decomp_ctxt *const	context,
		const uint8_t *	packet,
		const size_t	length,
		struct rohc_extr_bits *const	bits
	)

Parse the IP 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

int ip_parse_ext3	(	const struct rohc_decomp_ctxt *const	context,
		const uint8_t *const	rohc_data,
		const size_t	rohc_data_len,
		const rohc_packet_t	packet_type,
		struct rohc_extr_bits *const	bits
	)

Parse the extension 3 of the UOR-2 packet.


 Extension 3 for non-RTP profiles (5.7.5 & 5.11.4):

       0     1     2     3     4     5     6     7
    +-----+-----+-----+-----+-----+-----+-----+-----+
 1  |  1     1  |  S  |   Mode    |  I  | ip  | ip2 |
    +-----+-----+-----+-----+-----+-----+-----+-----+
 2  |            Inner IP header flags        |     |  if ip = 1
    +-----+-----+-----+-----+-----+-----+-----+-----+
 3  |            Outer IP header flags              |  if ip2 = 1
    +-----+-----+-----+-----+-----+-----+-----+-----+
 4  |                      SN                       |  if S = 1
    +-----+-----+-----+-----+-----+-----+-----+-----+
    |                                               |
 5  /            Inner IP header fields             /  variable,
    |                                               |  if ip = 1
    +-----+-----+-----+-----+-----+-----+-----+-----+
 6  |                     IP-ID                     |  2 octets, if I = 1
    +-----+-----+-----+-----+-----+-----+-----+-----+
    |                                               |
 7  /            Outer IP header fields             /  variable,
    |                                               |  if ip2 = 1
    +-----+-----+-----+-----+-----+-----+-----+-----+

Parameters:

	context	The decompression context
	rohc_data	The ROHC data to parse
	rohc_data_len	The length of the ROHC data to parse
	packet_type	The type of ROHC packet to parse
	bits	IN: the bits already found in base header OUT: the bits found in the extension header 3

Returns:: The data length read from the ROHC packet, -1 in case of error

int parse_inner_header_flags	(	const struct rohc_decomp_ctxt *const	context,
		const uint8_t *const	flags,
		const uint8_t *	fields,
		const size_t	length,
		struct rohc_extr_ip_bits *const	bits
	)

Parse the inner IP header flags and fields.

Store the values in an IP header info structure.


  Inner IP header flags (5.7.5):

       0     1     2     3     4     5     6     7
     ..... ..... ..... ..... ..... ..... ..... .....
    | TOS | TTL | DF  | PR  | IPX | NBO | RND | ip2 |  if ip = 1
     ..... ..... ..... ..... ..... ..... ..... .....

  Inner IP header fields (5.7.5):

    ..... ..... ..... ..... ..... ..... ..... .....
   |         Type of Service/Traffic Class         |  if TOS = 1
    ..... ..... ..... ..... ..... ..... ..... .....
   |         Time to Live/Hop Limit                |  if TTL = 1
    ..... ..... ..... ..... ..... ..... ..... .....
   |         Protocol/Next Header                  |  if PR = 1
    ..... ..... ..... ..... ..... ..... ..... .....
   /         IP extension headers                  /  variable,
    ..... ..... ..... ..... ..... ..... ..... .....   if IPX = 1

Parameters:

	context	The decompression context
	flags	The ROHC flags that indicate which IP fields are present in the packet
	fields	The ROHC packet part that contains some IP header fields
	length	The length of the ROHC packet part that contains some IP header fields
	bits	OUT: The bits extracted from extension 3

Returns:: The data length read from the ROHC packet, -1 in case of error

int parse_outer_header_flags	(	const struct rohc_decomp_ctxt *const	context,
		const uint8_t *const	flags,
		const uint8_t *	fields,
		const size_t	length,
		struct rohc_extr_ip_bits *const	bits
	)

Parse the outer IP header flags and fields.

Store the values in an IP header info structure.


  Outer IP header flags (5.7.5):

       0     1     2     3     4     5     6     7
     ..... ..... ..... ..... ..... ..... ..... .....
    | TOS2| TTL2| DF2 | PR2 |IPX2 |NBO2 |RND2 |  I2 |  if ip2 = 1
     ..... ..... ..... ..... ..... ..... ..... .....

  Outer IP header fields

     ..... ..... ..... ..... ..... ..... ..... .....
    |      Type of Service/Traffic Class            |  if TOS2 = 1
     ..... ..... ..... ..... ..... ..... ..... .....
    |         Time to Live/Hop Limit                |  if TTL2 = 1
     ..... ..... ..... ..... ..... ..... ..... .....
    |         Protocol/Next Header                  |  if PR2 = 1
     ..... ..... ..... ..... ..... ..... ..... .....
    /         IP extension header(s)                /  variable,
     ..... ..... ..... ..... ..... ..... ..... .....    if IPX2 = 1
    |                  IP-ID                        |  2 octets,
     ..... ..... ..... ..... ..... ..... ..... .....    if I2 = 1

Parameters:

	context	The decompression context
	flags	The ROHC flags that indicate which IP fields are present in the packet
	fields	The ROHC packet part that contain some IP header fields
	length	The length of the ROHC packet part that contains some IP header fields
	bits	OUT: The bits extracted from extension 3

Returns:: The data length read from the ROHC packet, -1 in case of error

Variable Documentation

struct rohc_decomp_profile d_ip_profile

Initial value:

{
        .id              = ROHC_PROFILE_IP, 
        .msn_max_bits    = 16,
        .new_context     = (rohc_decomp_new_context_t) d_ip_create,
        .free_context    = (rohc_decomp_free_context_t) d_ip_destroy,
        .detect_pkt_type = ip_detect_packet_type,
        .parse_pkt       = (rohc_decomp_parse_pkt_t) rfc3095_decomp_parse_pkt,
        .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 IP-only profile as described in the RFC 3843.

d_ip.c File Reference

Functions

Variables

Detailed Description

Function Documentation

Variable Documentation