d_esp.c File Reference

ROHC ESP decompression profile. More...

#include "rohc_decomp_rfc3095.h"
#include "d_ip.h"
#include "rohc_traces_internal.h"
#include "rohc_debug.h"
#include "rohc_utils.h"
#include "crc.h"
#include "protocols/esp.h"
#include "schemes/decomp_wlsb.h"
#include <stdint.h>
#include <string.h>
#include <assert.h>

Include dependency graph for d_esp.c:

Data Structures
struct	d_esp_context
	Define the ESP part of the decompression profile context. More...

Functions
static bool	d_esp_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 ESP decompression context. More...
static void	d_esp_destroy (struct rohc_decomp_rfc3095_ctxt *const rfc3095_ctxt, const struct rohc_decomp_volat_ctxt *const volat_ctxt)
	Destroy the context. More...
static int	esp_parse_static_esp (const struct rohc_decomp_ctxt *const context, const uint8_t *packet, size_t length, struct rohc_extr_bits *const bits)
	Parse the ESP static part of the ROHC packet. More...
static int	esp_parse_dynamic_esp (const struct rohc_decomp_ctxt *const context, const uint8_t *packet, const size_t length, struct rohc_extr_bits *const bits)
	Parse the ESP dynamic part of the ROHC packet. More...
static bool	esp_decode_values_from_bits (const struct rohc_decomp_ctxt *context, const struct rohc_extr_bits *const bits, struct rohc_decoded_values *const decoded)
	Decode ESP values from extracted bits. More...
static int	esp_build_uncomp_esp (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 ESP header. More...
static void	esp_update_context (struct rohc_decomp_ctxt *const context, const struct rohc_decoded_values *const decoded)
	Update context with decoded ESP values. More...

Variables
const struct rohc_decomp_profile	d_esp_profile
	Define the decompression part of the ESP profile as described in the RFC 3095. More...

Detailed Description

ROHC ESP decompression profile.

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_esp_create()

static bool d_esp_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 ESP 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 ESP context was successfully created, false if a problem occurred

d_esp_destroy()

static void d_esp_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

esp_build_uncomp_esp()

static int esp_build_uncomp_esp ( 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 ESP header.

Parameters

context	The decompression context
decoded	The values decoded from the ROHC header
dest	The buffer to store the ESP header (MUST be at least of sizeof(struct esphdr) length)
payload_len	The length of the ESP payload

Returns

The length of the next header (ie. the ESP header), -1 in case of error

esp_decode_values_from_bits()

static bool esp_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 ESP values from extracted bits.

The following values are decoded:

• ESP SPI

Parameters

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

Returns

true if decoding is successful, false otherwise

esp_parse_dynamic_esp()

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

static

Parse the ESP dynamic part of the ROHC packet.

Parameters

context	The decompression context
packet	The ROHC packet to decode
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

esp_parse_static_esp()

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

static

Parse the ESP static part of the ROHC packet.

Parameters

context	The decompression context
packet	The ROHC packet to decode
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

esp_update_context()

static void esp_update_context ( struct rohc_decomp_ctxt *const  context, const struct rohc_decoded_values *const  decoded  )

static

Update context with decoded ESP values.

The following decoded values are updated in context:

• ESP SPI

Parameters

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

Variable Documentation

d_esp_profile

const struct rohc_decomp_profile d_esp_profile

Initial value:

=
{
        .id              = ROHC_PROFILE_ESP, 
        .msn_max_bits    = 32,
        .new_context     = (rohc_decomp_new_context_t) d_esp_create,
        .free_context    = (rohc_decomp_free_context_t) d_esp_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 ESP profile as described in the RFC 3095.