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wireshark/epan/dissectors/packet-sndcp-xid.c

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/* packet-sndcp-xid.c
* Routines for Subnetwork Dependent Convergence Protocol (SNDCP) XID dissection
* Used to dissect XID compression parameters negotiated in GSM (TS44.065)
* Copyright 2008, Vincent Helfre <vincent.helfre [AT] ericsson.com>
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "config.h"
#include <epan/packet.h>
/* Parameter types: TS 44.065 8
*/
#define SNDCP_VERSION_PAR_TYPE 0
#define DATA_COMPRESSION_PAR_TYPE 1
#define PROTOCOL_COMPRESSION_PAR_TYPE 2
/* Algorithm identifiers: TS 44.065 6.6.1.1.4 and 6.5.1.1.4
*/
#define ALGO_V42BIS 0
#define ALGO_V44 1
#define ALGO_RFC1144 0
#define ALGO_RFC2507 1
#define ALGO_ROHC 2
void proto_register_sndcp_xid(void);
static const value_string sndcp_xid_dcomp_algo_str[] = {
{0x0, "V.42 bis"},
{0x1, "V.44"},
{0, NULL}
};
static const value_string sndcp_xid_pcomp_algo_str[] = {
{0x0, "RFC 1144"},
{0x1, "RFC 2507"},
{0x2, "ROHC (RFC 3095)"},
{0, NULL}
};
typedef struct
{
guint8 nb_of_dcomp_pcomp; /* note that a DCOMP or a PCOMP is 4 bit wide */
guint16 (**func_array_ptr) (tvbuff_t *, proto_tree *, guint16);
} algo_parameters_t;
/* Initialize the protocol and registered fields
*/
static int proto_sndcp_xid = -1;
/* These fields are used to store store the algorithm ID
* When the P bit is not set, try to decode the algo based on what whas stored.
* Entity ranges from 0 to 31 (6.5.1.1.3)
*/
static guint8 dcomp_entity_algo_id[32]={-1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1};
static guint8 pcomp_entity_algo_id[32]={-1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1};
/* L3 XID parsing */
static int hf_sndcp_xid_type = -1;
static int hf_sndcp_xid_len = -1;
static int hf_sndcp_xid_value = -1;
static int hf_sndcp_xid_comp_pbit = -1;
static int hf_sndcp_xid_comp_spare_byte1 = -1;
static int hf_sndcp_xid_comp_entity = -1;
static int hf_sndcp_xid_comp_spare_byte2 = -1;
static int hf_sndcp_xid_comp_algo_id = -1;
static int hf_sndcp_xid_comp_len = -1;
/* There is currently a maximum of 15 DCOMP/PCOMP: 6.5.1.1.5 */
static int hf_sndcp_xid_comp[15] = {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1};
static int hf_sndcp_xid_comp_spare = -1;
static int hf_element_applicable_nsapi_15 = -1;
static int hf_element_applicable_nsapi_14 = -1;
static int hf_element_applicable_nsapi_13 = -1;
static int hf_element_applicable_nsapi_12 = -1;
static int hf_element_applicable_nsapi_11 = -1;
static int hf_element_applicable_nsapi_10 = -1;
static int hf_element_applicable_nsapi_9 = -1;
static int hf_element_applicable_nsapi_8 = -1;
static int hf_element_applicable_nsapi_7 = -1;
static int hf_element_applicable_nsapi_6 = -1;
static int hf_element_applicable_nsapi_5 = -1;
static int hf_element_applicable_nsapi_spare = -1;
static int hf_sndcp_xid_rfc1144_s0 = -1;
static int hf_sndcp_xid_rfc2507_f_max_period_msb = -1;
static int hf_sndcp_xid_rfc2507_f_max_period_lsb = -1;
static int hf_sndcp_xid_rfc2507_f_max_time = -1;
static int hf_sndcp_xid_rfc2507_max_header = -1;
static int hf_sndcp_xid_rfc2507_tcp_space = -1;
static int hf_sndcp_xid_rfc2507_non_tcp_space_msb = -1;
static int hf_sndcp_xid_rfc2507_non_tcp_space_lsb = -1;
static int hf_sndcp_xid_rohc_max_cid_spare = -1;
static int hf_sndcp_xid_rohc_max_cid_msb = -1;
static int hf_sndcp_xid_rohc_max_cid_lsb = -1;
static int hf_sndcp_xid_rohc_max_header = -1;
static int hf_sndcp_xid_rohc_profile_msb = -1;
static int hf_sndcp_xid_rohc_profile_lsb = -1;
static int hf_sndcp_xid_V42bis_p0_spare = -1;
static int hf_sndcp_xid_V42bis_p0 = -1;
static int hf_sndcp_xid_V42bis_p1_msb = -1;
static int hf_sndcp_xid_V42bis_p1_lsb = -1;
static int hf_sndcp_xid_V42bis_p2 = -1;
static int hf_sndcp_xid_V44_c0 = -1;
static int hf_sndcp_xid_V44_c0_spare = -1;
static int hf_sndcp_xid_V44_p0_spare = -1;
static int hf_sndcp_xid_V44_p0 = -1;
static int hf_sndcp_xid_V44_p1t_msb = -1;
static int hf_sndcp_xid_V44_p1t_lsb = -1;
static int hf_sndcp_xid_V44_p1r_msb = -1;
static int hf_sndcp_xid_V44_p1r_lsb = -1;
static int hf_sndcp_xid_V44_p3t_msb = -1;
static int hf_sndcp_xid_V44_p3t_lsb = -1;
static int hf_sndcp_xid_V44_p3r_msb = -1;
static int hf_sndcp_xid_V44_p3r_lsb = -1;
/* Initialize the subtree pointers
*/
static gint ett_sndcp_xid = -1;
static gint ett_sndcp_xid_version_field = -1;
static gint ett_sndcp_comp_field = -1;
static void parse_compression_parameters(tvbuff_t *tvb, proto_tree *tree, gboolean dcomp);
/******************************************************/
/* Compression algorithms element dissector functions */
/******************************************************/
static guint16 parse_applicable_nsapi(tvbuff_t *tvb, proto_tree *tree, guint16 offset)
{
guint8 nsapi_byte1, nsapi_byte2;
nsapi_byte1 = tvb_get_guint8(tvb, offset);
nsapi_byte2 = tvb_get_guint8(tvb, offset+1);
proto_tree_add_uint(tree, hf_element_applicable_nsapi_15, tvb, offset, 1, nsapi_byte1);
proto_tree_add_uint(tree, hf_element_applicable_nsapi_14, tvb, offset, 1, nsapi_byte1);
proto_tree_add_uint(tree, hf_element_applicable_nsapi_13, tvb, offset, 1, nsapi_byte1);
proto_tree_add_uint(tree, hf_element_applicable_nsapi_12, tvb, offset, 1, nsapi_byte1);
proto_tree_add_uint(tree, hf_element_applicable_nsapi_11, tvb, offset, 1, nsapi_byte1);
proto_tree_add_uint(tree, hf_element_applicable_nsapi_10, tvb, offset, 1, nsapi_byte1);
proto_tree_add_uint(tree, hf_element_applicable_nsapi_9, tvb, offset, 1, nsapi_byte1);
proto_tree_add_uint(tree, hf_element_applicable_nsapi_8, tvb, offset, 1, nsapi_byte1);
proto_tree_add_uint(tree, hf_element_applicable_nsapi_7, tvb, offset+1, 1, nsapi_byte2);
proto_tree_add_uint(tree, hf_element_applicable_nsapi_6, tvb, offset+1, 1, nsapi_byte2);
proto_tree_add_uint(tree, hf_element_applicable_nsapi_5, tvb, offset+1, 1, nsapi_byte2);
proto_tree_add_uint(tree, hf_element_applicable_nsapi_spare, tvb, offset+1, 1, nsapi_byte2);
return 2U;
}
static guint16 parse_rfc1144_s0(tvbuff_t *tvb, proto_tree *tree, guint16 offset)
{
guint8 s0;
s0 = tvb_get_guint8(tvb, offset);
proto_tree_add_uint(tree, hf_sndcp_xid_rfc1144_s0, tvb, offset, 1, s0);
return 1U;
}
static guint16 parse_rfc2507_f_max_period(tvbuff_t *tvb, proto_tree *tree, guint16 offset)
{
guint8 f_max_period_byte1, f_max_period_byte2;
f_max_period_byte1 = tvb_get_guint8(tvb, offset);
f_max_period_byte2 = tvb_get_guint8(tvb, offset+1);
proto_tree_add_uint(tree, hf_sndcp_xid_rfc2507_f_max_period_msb, tvb, offset, 1, f_max_period_byte1);
proto_tree_add_uint(tree, hf_sndcp_xid_rfc2507_f_max_period_lsb, tvb, offset, 1, f_max_period_byte2);
return 2U;
}
static guint16 parse_rfc2507_f_max_time(tvbuff_t *tvb, proto_tree *tree, guint16 offset)
{
guint8 f_max_time;
f_max_time = tvb_get_guint8(tvb, offset);
proto_tree_add_uint(tree, hf_sndcp_xid_rfc2507_f_max_time, tvb, offset, 1, f_max_time);
return 1U;
}
static guint16 parse_rfc2507_max_header(tvbuff_t *tvb, proto_tree *tree, guint16 offset)
{
guint8 max_header;
max_header = tvb_get_guint8(tvb, offset);
proto_tree_add_uint(tree, hf_sndcp_xid_rfc2507_max_header, tvb, offset, 1, max_header);
return 1U;
}
static guint16 parse_rfc2507_tcp_space(tvbuff_t *tvb, proto_tree *tree, guint16 offset)
{
guint8 tcp_space;
tcp_space = tvb_get_guint8(tvb, offset);
proto_tree_add_uint(tree, hf_sndcp_xid_rfc2507_tcp_space, tvb, offset, 1, tcp_space);
return 1U;
}
static guint16 parse_rfc2507_non_tcp_space(tvbuff_t *tvb, proto_tree *tree, guint16 offset)
{
guint8 tcp_space_msb, tcp_space_lsb;
tcp_space_msb = tvb_get_guint8(tvb, offset);
tcp_space_lsb = tvb_get_guint8(tvb, offset+1);
proto_tree_add_uint(tree, hf_sndcp_xid_rfc2507_non_tcp_space_msb, tvb, offset, 1, tcp_space_msb);
proto_tree_add_uint(tree, hf_sndcp_xid_rfc2507_non_tcp_space_lsb, tvb, offset, 1, tcp_space_lsb);
return 2U;
}
static guint16 parse_rohc_max_cid(tvbuff_t *tvb, proto_tree *tree, guint16 offset)
{
guint8 max_cid_msb, max_cid_lsb;
max_cid_msb = tvb_get_guint8(tvb, offset);
max_cid_lsb = tvb_get_guint8(tvb, offset+1);
proto_tree_add_uint(tree, hf_sndcp_xid_rohc_max_cid_spare, tvb, offset, 1, max_cid_msb);
proto_tree_add_uint(tree, hf_sndcp_xid_rohc_max_cid_msb, tvb, offset, 1, max_cid_msb);
proto_tree_add_uint(tree, hf_sndcp_xid_rohc_max_cid_lsb, tvb, offset+1, 1, max_cid_lsb);
return 2U;
}
static guint16 parse_rohc_max_header(tvbuff_t *tvb, proto_tree *tree, guint16 offset)
{
guint8 max_header;
max_header = tvb_get_guint8(tvb, offset+1);
proto_tree_add_uint(tree, hf_sndcp_xid_rohc_max_header, tvb, offset+1, 1, max_header);
return 2U;
}
static guint16 parse_rohc_profile(tvbuff_t *tvb, proto_tree *tree, guint16 offset)
{
guint8 profile_msb, profile_lsb;
profile_msb = tvb_get_guint8(tvb, offset);
profile_lsb = tvb_get_guint8(tvb, offset+1);
proto_tree_add_uint(tree, hf_sndcp_xid_rohc_profile_msb, tvb, offset, 1, profile_msb);
proto_tree_add_uint(tree, hf_sndcp_xid_rohc_profile_lsb, tvb, offset+1, 1, profile_lsb);
return 2U;
}
static guint16 parse_V42bis_p0(tvbuff_t *tvb, proto_tree *tree, guint16 offset)
{
guint8 p0;
p0 = tvb_get_guint8(tvb, offset);
proto_tree_add_uint(tree, hf_sndcp_xid_V42bis_p0_spare, tvb, offset, 1, p0);
proto_tree_add_uint(tree, hf_sndcp_xid_V42bis_p0, tvb, offset, 1, p0);
return 1U;
}
static guint16 parse_V42bis_p1(tvbuff_t *tvb, proto_tree *tree, guint16 offset)
{
guint8 p1_msb, p1_lsb;
p1_msb = tvb_get_guint8(tvb, offset);
p1_lsb = tvb_get_guint8(tvb, offset+1);
proto_tree_add_uint(tree, hf_sndcp_xid_V42bis_p1_msb, tvb, offset, 1, p1_msb);
proto_tree_add_uint(tree, hf_sndcp_xid_V42bis_p1_lsb, tvb, offset+1, 1, p1_lsb);
return 2U;
}
static guint16 parse_V42bis_p2(tvbuff_t *tvb, proto_tree *tree, guint16 offset)
{
guint8 p2;
p2 = tvb_get_guint8(tvb, offset);
proto_tree_add_uint(tree, hf_sndcp_xid_V42bis_p2, tvb, offset, 1, p2);
return 1U;
}
static guint16 parse_V44_c0(tvbuff_t *tvb, proto_tree *tree, guint16 offset)
{
guint8 c0;
c0 = tvb_get_guint8(tvb, offset);
proto_tree_add_uint(tree, hf_sndcp_xid_V44_c0_spare, tvb, offset, 1, c0);
proto_tree_add_uint(tree, hf_sndcp_xid_V44_c0, tvb, offset, 1, c0);
return 1U;
}
static guint16 parse_V44_p0(tvbuff_t *tvb, proto_tree *tree, guint16 offset)
{
guint8 p0;
p0 = tvb_get_guint8(tvb, offset);
proto_tree_add_uint(tree, hf_sndcp_xid_V44_p0_spare, tvb, offset, 1, p0);
proto_tree_add_uint(tree, hf_sndcp_xid_V44_p0, tvb, offset, 1, p0);
return 1U;
}
static guint16 parse_V44_p1t(tvbuff_t *tvb, proto_tree *tree, guint16 offset)
{
guint8 p1t_msb, p1t_lsb;
p1t_msb = tvb_get_guint8(tvb, offset);
p1t_lsb = tvb_get_guint8(tvb, offset+1);
proto_tree_add_uint(tree, hf_sndcp_xid_V44_p1t_msb, tvb, offset, 1, p1t_msb);
proto_tree_add_uint(tree, hf_sndcp_xid_V44_p1t_lsb, tvb, offset+1, 1, p1t_lsb);
return 2U;
}
static guint16 parse_V44_p1r(tvbuff_t *tvb, proto_tree *tree, guint16 offset)
{
guint8 p1r_msb, p1r_lsb;
p1r_msb = tvb_get_guint8(tvb, offset);
p1r_lsb = tvb_get_guint8(tvb, offset+1);
proto_tree_add_uint(tree, hf_sndcp_xid_V44_p1r_msb, tvb, offset, 1, p1r_msb);
proto_tree_add_uint(tree, hf_sndcp_xid_V44_p1r_lsb, tvb, offset+1, 1, p1r_lsb);
return 2U;
}
static guint16 parse_V44_p3t(tvbuff_t *tvb, proto_tree *tree, guint16 offset)
{
guint8 p3t_msb, p3t_lsb;
p3t_msb = tvb_get_guint8(tvb, offset);
p3t_lsb = tvb_get_guint8(tvb, offset+1);
proto_tree_add_uint(tree, hf_sndcp_xid_V44_p3t_msb, tvb, offset, 1, p3t_msb);
proto_tree_add_uint(tree, hf_sndcp_xid_V44_p3t_lsb, tvb, offset+1, 1, p3t_lsb);
return 2U;
}
static guint16 parse_V44_p3r(tvbuff_t *tvb, proto_tree *tree, guint16 offset)
{
guint8 p3r_msb, p3r_lsb;
p3r_msb = tvb_get_guint8(tvb, offset);
p3r_lsb = tvb_get_guint8(tvb, offset+1);
proto_tree_add_uint(tree, hf_sndcp_xid_V44_p3r_msb, tvb, offset, 1, p3r_msb);
proto_tree_add_uint(tree, hf_sndcp_xid_V44_p3r_lsb, tvb, offset+1, 1, p3r_lsb);
return 2U;
}
/***************************************************/
/* Compression algorithms element dissector arrays */
/***************************************************/
static guint16 (*rfc1144_elem_fcn[])(tvbuff_t *, proto_tree *, guint16) = {
parse_applicable_nsapi,
parse_rfc1144_s0,
NULL
};
static guint16 (*rfc2507_elem_fcn[])(tvbuff_t *, proto_tree *, guint16) = {
parse_applicable_nsapi,
parse_rfc2507_f_max_period,
parse_rfc2507_f_max_time,
parse_rfc2507_max_header,
parse_rfc2507_tcp_space,
parse_rfc2507_non_tcp_space,
NULL
};
static guint16 (*rohc_elem_fcn[])(tvbuff_t *, proto_tree *, guint16) = {
parse_applicable_nsapi,
parse_rohc_max_cid,
parse_rohc_max_header,
parse_rohc_profile, /* Profile 1 */
parse_rohc_profile, /* Profile 2 */
parse_rohc_profile, /* Profile 3 */
parse_rohc_profile, /* Profile 4 */
parse_rohc_profile, /* Profile 5 */
parse_rohc_profile, /* Profile 6 */
parse_rohc_profile, /* Profile 7 */
parse_rohc_profile, /* Profile 8 */
parse_rohc_profile, /* Profile 9 */
parse_rohc_profile, /* Profile 10 */
parse_rohc_profile, /* Profile 11 */
parse_rohc_profile, /* Profile 12 */
parse_rohc_profile, /* Profile 13 */
parse_rohc_profile, /* Profile 14 */
parse_rohc_profile, /* Profile 15 */
parse_rohc_profile, /* Profile 16 */
NULL
};
/* Array containing the number of pcomp and the function array pointer */
static algo_parameters_t pcomp_algo_pars[] = {
{2, rfc1144_elem_fcn},
{5, rfc2507_elem_fcn},
{2, rohc_elem_fcn}
};
/* Data compression algorithms */
static guint16 (*v42bis_elem_fcn[])(tvbuff_t *, proto_tree *, guint16) = {
parse_applicable_nsapi,
parse_V42bis_p0,
parse_V42bis_p1,
parse_V42bis_p2,
NULL
};
static guint16 (*v44_elem_fcn[])(tvbuff_t *, proto_tree *, guint16) = {
parse_applicable_nsapi,
parse_V44_c0,
parse_V44_p0,
parse_V44_p1t,
parse_V44_p1r,
parse_V44_p3t,
parse_V44_p3r,
NULL
};
/* Array containing the number of dcomp and the function array pointer */
static algo_parameters_t dcomp_algo_pars[] = {
{1, v42bis_elem_fcn},
{2, v44_elem_fcn},
};
/* Code to actually dissect the packets
*/
static int
dissect_sndcp_xid(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree, void* data _U_)
{
/* Set up structures needed to add the protocol subtree and manage it
*/
proto_item *ti, *dcomp_item;
proto_tree *sndcp_tree, *version_tree, *dcomp_tree, *pcomp_tree;
guint16 offset = 0, l3_param_len;
guint8 parameter_type, parameter_len;
/* create display subtree for the protocol
*/
ti = proto_tree_add_item(tree, proto_sndcp_xid, tvb, 0, -1, ENC_NA);
sndcp_tree = proto_item_add_subtree(ti, ett_sndcp_xid);
l3_param_len = tvb_reported_length(tvb);
while (offset < l3_param_len-1)
{
parameter_type = tvb_get_guint8(tvb, offset);
parameter_len = tvb_get_guint8(tvb, offset+1);
if (parameter_type == SNDCP_VERSION_PAR_TYPE)
{
guint8 value = tvb_get_guint8(tvb, offset+2);
version_tree = proto_tree_add_subtree_format(sndcp_tree, tvb, offset, parameter_len+2,
ett_sndcp_xid_version_field, NULL, "Version (SNDCP version number) - Value %d", value);
proto_tree_add_uint(version_tree, hf_sndcp_xid_type, tvb, offset,
1, parameter_type);
proto_tree_add_uint(version_tree, hf_sndcp_xid_len, tvb, offset+1,
1, parameter_len);
proto_tree_add_uint(version_tree, hf_sndcp_xid_value, tvb, offset+2,
1, value);
offset += 3;
}
else if (parameter_type == DATA_COMPRESSION_PAR_TYPE)
{
tvbuff_t * dcomp_tvb;
dcomp_tree = proto_tree_add_subtree(sndcp_tree, tvb, offset, parameter_len+2,
ett_sndcp_comp_field, &dcomp_item, "Data Compression");
proto_tree_add_uint(dcomp_tree, hf_sndcp_xid_type, tvb, offset,
1, parameter_type);
proto_tree_add_uint(dcomp_tree, hf_sndcp_xid_len, tvb, offset+1,
1, parameter_len);
offset += 2;
dcomp_tvb = tvb_new_subset_length(tvb, offset, parameter_len);
parse_compression_parameters(dcomp_tvb, dcomp_tree, TRUE);
offset += parameter_len;
}
else if (parameter_type == PROTOCOL_COMPRESSION_PAR_TYPE)
{
tvbuff_t * pcomp_tvb;
pcomp_tree = proto_tree_add_subtree(sndcp_tree, tvb, offset, parameter_len+2,
ett_sndcp_comp_field, NULL, "Protocol Control Information Compression");
proto_tree_add_uint(pcomp_tree, hf_sndcp_xid_type, tvb, offset,
1, parameter_type);
proto_tree_add_uint(pcomp_tree, hf_sndcp_xid_len, tvb, offset+1,
1, parameter_len);
offset += 2;
pcomp_tvb = tvb_new_subset_length(tvb, offset, parameter_len);
parse_compression_parameters(pcomp_tvb, pcomp_tree, FALSE);
offset += parameter_len;
}
else
{
break; /* error: exit */
}
}
return tvb_captured_length(tvb);
}
static void parse_compression_parameters(tvbuff_t *tvb, proto_tree *tree, gboolean dcomp)
{
guint8 entity, len, algo_id;
guint8 number_of_comp, i;
gboolean p_bit_set;
algo_parameters_t * algo_pars;
guint8 function_index;
proto_tree *comp_entity_tree = NULL;
guint16 tvb_len, offset=0 , new_offset, entity_offset;
value_string const * comp_algo_str;
tvb_len = tvb_reported_length(tvb);
if (tvb_len < 3) return; /* entity, algo and length bytes should always be present 6.5.1.1 and 6.6.1.1 */
/* Loop to decode each entity (cf Figure 10) */
while (offset < tvb_len)
{
/* Read the entity byte */
entity = tvb_get_guint8(tvb, offset);
p_bit_set = ((entity & 0x80) == 0x80) ? 1 : 0;
entity = entity & 0x1F;
/* P bit is set: means that algo identifier and dcomp are present */
if (p_bit_set)
{
/* Read the algorithm id. TODO: store the algo in a different variable for each different entity */
algo_id = tvb_get_guint8(tvb, offset+1) & 0x1F;
/* sanity check: check that the algo id that will be used inside the array has a valid range */
if (dcomp)
{
if(algo_id <= ALGO_V44)
{
algo_pars = dcomp_algo_pars;
dcomp_entity_algo_id[entity] = algo_id;
comp_algo_str = sndcp_xid_dcomp_algo_str;
}
else return;
}
else
{
if (algo_id <= ALGO_ROHC)
{
algo_pars = pcomp_algo_pars;
pcomp_entity_algo_id[entity] = algo_id;
comp_algo_str = sndcp_xid_pcomp_algo_str;
}
else return;
}
/* Read the length */
len = tvb_get_guint8(tvb, offset+2);
comp_entity_tree = proto_tree_add_subtree_format(tree, tvb, offset, len + 3,
ett_sndcp_comp_field, NULL, "Entity %d, Algorithm %s",
entity & 0x1F, val_to_str(algo_id & 0x1F, comp_algo_str,"Undefined Algorithm Identifier:%X"));
proto_tree_add_uint(comp_entity_tree, hf_sndcp_xid_comp_pbit, tvb, offset, 1, p_bit_set << 7);
proto_tree_add_uint(comp_entity_tree, hf_sndcp_xid_comp_spare_byte1, tvb, offset, 1, entity);
proto_tree_add_uint(comp_entity_tree, hf_sndcp_xid_comp_entity, tvb, offset, 1, entity);
proto_tree_add_uint(comp_entity_tree, hf_sndcp_xid_comp_spare_byte2, tvb, offset+1, 1, algo_id);
proto_tree_add_uint(comp_entity_tree, hf_sndcp_xid_comp_algo_id, tvb, offset+1, 1, algo_id);
proto_tree_add_uint(comp_entity_tree, hf_sndcp_xid_comp_len, tvb, offset+2, 1, len);
/* Read the dcomp/pcomp field */
offset += 3; /* entity_offset will be used as the offset from length byte */
number_of_comp = algo_pars[algo_id].nb_of_dcomp_pcomp;
for (i=0; i < (number_of_comp+1) / 2; i++)
{
guint8 byte;
byte = tvb_get_guint8(tvb, offset+i);
proto_tree_add_uint(comp_entity_tree, hf_sndcp_xid_comp[2*i], tvb, offset+i, 1, byte);
/* if there is an even number of dcomp/pcomp */
if (2*i+1 < number_of_comp)
{
proto_tree_add_uint(comp_entity_tree, hf_sndcp_xid_comp[2*i+1], tvb, offset+i, 1, byte);
}
/* else there is padding in the end */
else
{
proto_tree_add_uint(comp_entity_tree, hf_sndcp_xid_comp_spare, tvb, offset+i, 1, byte);
}
}
entity_offset = i;
function_index = 0;
/* Process the elements byte per byte */
while ((entity_offset < len) && (algo_pars[algo_id].func_array_ptr[function_index] != NULL))
{
new_offset = offset+entity_offset;
entity_offset += algo_pars[algo_id].func_array_ptr[function_index](tvb, comp_entity_tree, new_offset);
function_index++;
}
offset += entity_offset;
}
else /* P bit not set */
{
len = tvb_get_guint8(tvb, offset+1);
if (dcomp)
{
algo_pars = dcomp_algo_pars;
algo_id = dcomp_entity_algo_id[entity];
comp_algo_str = sndcp_xid_dcomp_algo_str;
}
else
{
algo_pars = pcomp_algo_pars;
algo_id = pcomp_entity_algo_id[entity];
comp_algo_str = sndcp_xid_pcomp_algo_str;
}
comp_entity_tree = proto_tree_add_subtree_format(tree, tvb, offset, len + 2,
ett_sndcp_comp_field, NULL, "Entity %d decoded as Algorithm %s",
entity & 0x1F, val_to_str(algo_id & 0x1F, comp_algo_str,"Undefined Algorithm Identifier:%X"));
proto_tree_add_uint(comp_entity_tree, hf_sndcp_xid_comp_pbit, tvb, offset, 1, p_bit_set << 7);
proto_tree_add_uint(comp_entity_tree, hf_sndcp_xid_comp_spare_byte1, tvb, offset, 1, entity);
proto_tree_add_uint(comp_entity_tree, hf_sndcp_xid_comp_entity, tvb, offset, 1, entity);
proto_tree_add_uint(comp_entity_tree, hf_sndcp_xid_comp_len, tvb, offset+2, 1, len);
offset += 2;
entity_offset = 0;
function_index = 0;
if (dcomp)
{
if (algo_id > ALGO_V44) return;
}
else
{
if (algo_id > ALGO_ROHC) return;
}
/* Process the elements byte per byte */
while ((entity_offset < len) && (algo_pars[algo_id].func_array_ptr[function_index] != NULL))
{
new_offset = offset+entity_offset;
entity_offset += algo_pars[algo_id].func_array_ptr[function_index](tvb, comp_entity_tree, new_offset);
function_index++;
}
offset += entity_offset;
}
}
/* Else if length is lower than 3, the packet is not correctly formatted */
}
/* Register the protocol with Wireshark
this format is required because a script is used to build the C function
that calls all the protocol registration.
*/
void
proto_register_sndcp_xid(void)
{
/* Setup list of header fields
*/
static hf_register_info hf[] = {
/* L3 XID Parameter Parsing Info */
{&hf_sndcp_xid_type,
{ "Parameter type","llcgprs.l3xidpartype", FT_UINT8, BASE_DEC, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_len,
{ "Length","llcgprs.l3xidparlen", FT_UINT8, BASE_DEC, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_value,
{ "Value","llcgprs.l3xidparvalue", FT_UINT8, BASE_DEC, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_comp_pbit,
{ "P bit","llcgprs.l3xiddcomppbit", FT_UINT8, BASE_DEC, NULL, 0x80, "Data", HFILL}},
{&hf_sndcp_xid_comp_spare_byte1,
{ "Spare","llcgprs.l3xidspare", FT_UINT8, BASE_HEX, NULL, 0x60, "Ignore", HFILL}},
{&hf_sndcp_xid_comp_entity,
{ "Entity","llcgprs.l3xidentity", FT_UINT8, BASE_DEC, NULL, 0x1F, "Data", HFILL}},
{&hf_sndcp_xid_comp_spare_byte2,
{ "Spare","llcgprs.l3xidspare", FT_UINT8, BASE_HEX, NULL, 0xE0, "Ignore", HFILL}},
{&hf_sndcp_xid_comp_algo_id,
{ "Algorithm identifier","llcgprs.l3xidalgoid", FT_UINT8, BASE_DEC, NULL, 0x1F, "Data", HFILL}},
{&hf_sndcp_xid_comp_len,
{ "Length","llcgprs.l3xidcomplen", FT_UINT8, BASE_DEC, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_comp[0],
{ "DCOMP1","llcgprs.l3xiddcomp", FT_UINT8, BASE_DEC, NULL, 0xF0, "Data", HFILL}},
{&hf_sndcp_xid_comp[1],
{ "DCOMP2","llcgprs.l3xiddcomp", FT_UINT8, BASE_DEC, NULL, 0x0F, "Data", HFILL}},
{&hf_sndcp_xid_comp[2],
{ "DCOMP3","llcgprs.l3xiddcomp", FT_UINT8, BASE_DEC, NULL, 0xF0, "Data", HFILL}},
{&hf_sndcp_xid_comp[3],
{ "DCOMP4","llcgprs.l3xiddcomp", FT_UINT8, BASE_DEC, NULL, 0x0F, "Data", HFILL}},
{&hf_sndcp_xid_comp[4],
{ "DCOMP5","llcgprs.l3xiddcomp", FT_UINT8, BASE_DEC, NULL, 0xF0, "Data", HFILL}},
{&hf_sndcp_xid_comp[5],
{ "DCOMP6","llcgprs.l3xiddcomp", FT_UINT8, BASE_DEC, NULL, 0x0F, "Data", HFILL}},
{&hf_sndcp_xid_comp[6],
{ "DCOMP7","llcgprs.l3xiddcomp", FT_UINT8, BASE_DEC, NULL, 0xF0, "Data", HFILL}},
{&hf_sndcp_xid_comp[7],
{ "DCOMP8","llcgprs.l3xiddcomp", FT_UINT8, BASE_DEC, NULL, 0x0F, "Data", HFILL}},
{&hf_sndcp_xid_comp[8],
{ "DCOMP9","llcgprs.l3xiddcomp", FT_UINT8, BASE_DEC, NULL, 0xF0, "Data", HFILL}},
{&hf_sndcp_xid_comp[9],
{ "DCOMP10","llcgprs.l3xiddcomp", FT_UINT8, BASE_DEC, NULL, 0x0F, "Data", HFILL}},
{&hf_sndcp_xid_comp[10],
{ "DCOMP11","llcgprs.l3xiddcomp", FT_UINT8, BASE_DEC, NULL, 0xF0, "Data", HFILL}},
{&hf_sndcp_xid_comp[11],
{ "DCOMP12","llcgprs.l3xiddcomp", FT_UINT8, BASE_DEC, NULL, 0x0F, "Data", HFILL}},
{&hf_sndcp_xid_comp[12],
{ "DCOMP13","llcgprs.l3xiddcomp", FT_UINT8, BASE_DEC, NULL, 0xF0, "Data", HFILL}},
{&hf_sndcp_xid_comp[13],
{ "DCOMP14","llcgprs.l3xiddcomp", FT_UINT8, BASE_DEC, NULL, 0x0F, "Data", HFILL}},
{&hf_sndcp_xid_comp[14],
{ "DCOMP15","llcgprs.l3xiddcomp", FT_UINT8, BASE_DEC, NULL, 0xF0, "Data", HFILL}},
{&hf_sndcp_xid_comp_spare,
{ "Spare","llcgprs.l3xidspare", FT_UINT8, BASE_HEX, NULL, 0x0F, "Ignore", HFILL}},
{&hf_element_applicable_nsapi_15,
{ "NSAPI 15","sndcpxid.nsapi15", FT_UINT8, BASE_DEC, NULL, 0x80, "Data", HFILL}},
{&hf_element_applicable_nsapi_14,
{ "NSAPI 14","sndcpxid.nsapi14", FT_UINT8, BASE_DEC, NULL, 0x40, "Data", HFILL}},
{&hf_element_applicable_nsapi_13,
{ "NSAPI 13","sndcpxid.nsapi13", FT_UINT8, BASE_DEC, NULL, 0x20, "Data", HFILL}},
{&hf_element_applicable_nsapi_12,
{ "NSAPI 12","sndcpxid.nsapi12", FT_UINT8, BASE_DEC, NULL, 0x10, "Data", HFILL}},
{&hf_element_applicable_nsapi_11,
{ "NSAPI 11","sndcpxid.nsapi11", FT_UINT8, BASE_DEC, NULL, 0x08, "Data", HFILL}},
{&hf_element_applicable_nsapi_10,
{ "NSAPI 10","sndcpxid.nsapi10", FT_UINT8, BASE_DEC, NULL, 0x04, "Data", HFILL}},
{&hf_element_applicable_nsapi_9,
{ "NSAPI 9","sndcpxid.nsapi9", FT_UINT8, BASE_DEC, NULL, 0x02, "Data", HFILL}},
{&hf_element_applicable_nsapi_8,
{ "NSAPI 8","sndcpxid.nsapi8", FT_UINT8, BASE_DEC, NULL, 0x01, "Data", HFILL}},
{&hf_element_applicable_nsapi_7,
{ "NSAPI 7","sndcpxid.nsapi7", FT_UINT8, BASE_DEC, NULL, 0x80, "Data", HFILL}},
{&hf_element_applicable_nsapi_6,
{ "NSAPI 6","sndcpxid.nsapi6", FT_UINT8, BASE_DEC, NULL, 0x40, "Data", HFILL}},
{&hf_element_applicable_nsapi_5,
{ "NSAPI 5","sndcpxid.nsapi5", FT_UINT8, BASE_DEC, NULL, 0x20, "Data", HFILL}},
{&hf_element_applicable_nsapi_spare,
{ "Spare","sndcpxid.spare", FT_UINT8, BASE_DEC, NULL, 0x1F, "Ignore", HFILL}},
{&hf_sndcp_xid_rfc1144_s0,
{ "S0 - 1","sndcpxid.rfc1144_s0", FT_UINT8, BASE_DEC, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_rfc2507_f_max_period_msb,
{ "F Max Period MSB","sndcpxid.rfc2507_f_max_period_msb", FT_UINT8, BASE_HEX, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_rfc2507_f_max_period_lsb,
{ "F Max Period LSB","sndcpxid.rfc2507_f_max_period_lsb", FT_UINT8, BASE_HEX, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_rfc2507_f_max_time,
{ "F Max Time","sndcpxid.rfc2507_f_max_time", FT_UINT8, BASE_DEC, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_rfc2507_max_header,
{ "Max Header","sndcpxid.rfc2507_max_header", FT_UINT8, BASE_DEC, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_rfc2507_tcp_space,
{ "TCP Space","sndcpxid.rfc2507_max_tcp_space", FT_UINT8, BASE_DEC, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_rfc2507_non_tcp_space_msb,
{ "TCP non space MSB","sndcpxid.rfc2507_max_non_tcp_space_msb", FT_UINT8, BASE_HEX, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_rfc2507_non_tcp_space_lsb,
{ "TCP non space LSB","sndcpxid.rfc2507_max_non_tcp_space_lsb", FT_UINT8, BASE_HEX, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_rohc_max_cid_spare,
{ "Spare","sndcpxid.rohc_max_cid_spare", FT_UINT8, BASE_DEC, NULL, 0xC0, "Ignore", HFILL}},
{&hf_sndcp_xid_rohc_max_cid_msb,
{ "Max CID MSB","sndcpxid.rohc_max_cid_msb", FT_UINT8, BASE_HEX, NULL, 0x3F, "Data", HFILL}},
{&hf_sndcp_xid_rohc_max_cid_lsb,
{ "Max CID LSB","sndcpxid.rohc_max_cid_lsb", FT_UINT8, BASE_HEX, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_rohc_max_header,
{ "Max header","sndcpxid.rohc_max_header", FT_UINT8, BASE_DEC, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_rohc_profile_msb,
{ "Profile MSB","sndcpxid.rohc_profile_msb", FT_UINT8, BASE_HEX, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_rohc_profile_lsb,
{ "Profile LSB","sndcpxid.rohc_profile_lsb", FT_UINT8, BASE_HEX, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_V42bis_p0_spare,
{ "Spare","sndcpxid.V42bis_p0spare", FT_UINT8, BASE_DEC, NULL, 0xFC, "Ignore", HFILL}},
{&hf_sndcp_xid_V42bis_p0,
{ "P0","sndcpxid.V42bis_p0", FT_UINT8, BASE_HEX, NULL, 0x03, "Data", HFILL}},
{&hf_sndcp_xid_V42bis_p1_msb,
{ "P1 MSB","sndcpxid.V42bis_p1_msb", FT_UINT8, BASE_HEX, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_V42bis_p1_lsb,
{ "P1 LSB","sndcpxid.V42bis_p1_lsb", FT_UINT8, BASE_HEX, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_V42bis_p2,
{ "P2","sndcpxid.V42bis_p2", FT_UINT8, BASE_HEX, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_V44_c0_spare,
{ "P2","sndcpxid.V44_c0_spare", FT_UINT8, BASE_HEX, NULL, 0x3F, "Ignore", HFILL}},
{&hf_sndcp_xid_V44_c0,
{ "P2","sndcpxid.V44_c0", FT_UINT8, BASE_HEX, NULL, 0xC0, "Data", HFILL}},
{&hf_sndcp_xid_V44_p0_spare,
{ "Spare","sndcpxid.V44_p0spare", FT_UINT8, BASE_DEC, NULL, 0xFC, "Ignore", HFILL}},
{&hf_sndcp_xid_V44_p0,
{ "P0","sndcpxid.V44_p0", FT_UINT8, BASE_HEX, NULL, 0x03, "Data", HFILL}},
{&hf_sndcp_xid_V44_p1t_msb,
{ "P1t MSB","sndcpxid.V44_p1t_msb", FT_UINT8, BASE_HEX, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_V44_p1t_lsb,
{ "P1t LSB","sndcpxid.V44_p1t_lsb", FT_UINT8, BASE_HEX, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_V44_p1r_msb,
{ "P1r MSB","sndcpxid.V44_p1r_msb", FT_UINT8, BASE_HEX, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_V44_p1r_lsb,
{ "P1r LSB","sndcpxid.V44_p1r_lsb", FT_UINT8, BASE_HEX, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_V44_p3t_msb,
{ "P3t MSB","sndcpxid.V44_p3t_msb", FT_UINT8, BASE_HEX, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_V44_p3t_lsb,
{ "P3t LSB","sndcpxid.V44_p3t_lsb", FT_UINT8, BASE_HEX, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_V44_p3r_msb,
{ "P3r MSB","sndcpxid.V44_p3r_msb", FT_UINT8, BASE_HEX, NULL, 0xFF, "Data", HFILL}},
{&hf_sndcp_xid_V44_p3r_lsb,
{ "P3r LSB","sndcpxid.V44_p3r_lsb", FT_UINT8, BASE_HEX, NULL, 0xFF, "Data", HFILL}},
};
/* Setup protocol subtree array */
static gint *ett[] = {
&ett_sndcp_xid,
&ett_sndcp_xid_version_field,
&ett_sndcp_comp_field
};
/* Register the protocol name and description */
proto_sndcp_xid = proto_register_protocol("Subnetwork Dependent Convergence Protocol XID",
"SNDCP XID", "sndcpxid");
/* Required function calls to register the header fields and subtrees used */
proto_register_field_array(proto_sndcp_xid, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
register_dissector("sndcpxid", dissect_sndcp_xid, proto_sndcp_xid);
}
/*
* Editor modelines - http://www.wireshark.org/tools/modelines.html
*
* Local variables:
* c-basic-offset: 4
* tab-width: 8
* indent-tabs-mode: nil
* End:
*
* vi: set shiftwidth=4 tabstop=8 expandtab:
* :indentSize=4:tabSize=8:noTabs=true:
*/
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