1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
|
/* packet-smpte-2110-20.c
* SMPTE ST2110-20
*
* Copyright 2023, Sergey V. Lobanov <sergey@lobanov.in>
*
* References:
* SMPTE ST 2110-20:2022, Uncompressed Active Video
* RFC4175, RTP Payload Format for Uncompressed Video
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "config.h"
#include <epan/packet.h>
#include <epan/prefs.h>
#include <epan/proto.h>
#include <epan/proto_data.h>
#include "packet-rtp.h"
void proto_reg_handoff_st2110_20(void);
void proto_register_st2110_20(void);
static dissector_handle_t st2110_20_handle;
/* Initialize the protocol and registered fields */
static int proto_st2110_20 = -1;
static int proto_rtp = -1;
static int hf_st2110_ext_seqno = -1;
static int hf_st2110_seqno = -1;
static int hf_st2110_rtp_time = -1;
static int hf_st2110_srd_index = -1;
static int hf_st2110_srd_length = -1;
static int hf_st2110_field_ident = -1;
static int hf_st2110_row_num = -1;
static int hf_st2110_continuation = -1;
static int hf_st2110_srd_offset = -1;
static int hf_st2110_srd_data = -1;
static int hf_st2110_srd_rows = -1;
/* Initialize the subtree pointers */
static gint ett_st2110_20 = -1;
static gint ett_st2110_20_srd_row = -1;
static int
dissect_st2110_20(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree _U_, void* data _U_)
{
proto_item *item;
proto_tree *st2110_20_tree;
gint offset = 0;
struct _rtp_packet_info *rtp_pkt_info = (struct _rtp_packet_info *)p_get_proto_data(wmem_file_scope(), pinfo, proto_rtp, RTP_CONVERSATION_PROTO_DATA);
col_set_str(pinfo->cinfo, COL_PROTOCOL, "ST2110-20");
item = proto_tree_add_item(tree, proto_st2110_20, tvb, 0, -1, ENC_NA);
st2110_20_tree = proto_item_add_subtree(item, ett_st2110_20);
/* Extract original RTP sequence number from low bits */
guint32 rtp_seqno = (rtp_pkt_info != NULL) ? (rtp_pkt_info->extended_seqno & 0xFFFF) : 0;
/* ST2110-20 extended sequence number field */
guint32 ext_seqno = tvb_get_guint16(tvb, offset, ENC_BIG_ENDIAN);
/* Sequence number (RTP seqno is low bits, ST2110-20 ext seqno is high bits) */
guint32 seqno = (ext_seqno << 16) + rtp_seqno;
/* Extract original RTP timestamp */
guint32 rtp_time = (rtp_pkt_info != NULL) ? (guint32)(rtp_pkt_info->extended_timestamp & 0xFFFFFFFF) : 0;
proto_tree_add_item(st2110_20_tree, hf_st2110_ext_seqno, tvb, offset, 2, ENC_BIG_ENDIAN);
PROTO_ITEM_SET_GENERATED(
proto_tree_add_uint(st2110_20_tree, hf_st2110_seqno, tvb, offset, 2, seqno)
);
PROTO_ITEM_SET_GENERATED(
proto_tree_add_uint(st2110_20_tree, hf_st2110_rtp_time, NULL, 0, 0, rtp_time)
);
offset += 2; /* st2110-20 ext seqno */
/* According to ST2110-20:2022 6.2.1, max three SRD headers might be in a packet */
guint16 srd_lengths[3] = {0, 0, 0}; /* store for second pass */
proto_tree* srd_header_trees[3] = {NULL, NULL, NULL}; /* store for second pass */
guint8 srd_rows = 0; /* rows count */
guint16 first_row; /* first row number */
for (guint8 srd_idx = 0; srd_idx < 3 ; srd_idx++) {
proto_tree *srd_header_tree = proto_tree_add_subtree_format(st2110_20_tree, tvb, offset, 6,
ett_st2110_20_srd_row, &item, "Sample Row Data %u", srd_idx);
srd_header_trees[srd_idx] = srd_header_tree;
PROTO_ITEM_SET_GENERATED(
proto_tree_add_uint(srd_header_tree, hf_st2110_srd_index, NULL, 0, 0, srd_idx)
);
srd_lengths[srd_idx] = tvb_get_guint16(tvb, offset, ENC_BIG_ENDIAN);
proto_tree_add_item(srd_header_tree, hf_st2110_srd_length, tvb, offset, 2, ENC_BIG_ENDIAN);
offset += 2;
first_row = (srd_idx == 0) ? (tvb_get_guint16(tvb, offset, ENC_BIG_ENDIAN) & 0x7FFF) : first_row;
proto_tree_add_item(srd_header_tree, hf_st2110_field_ident, tvb, offset, 2, ENC_BIG_ENDIAN);
proto_tree_add_item(srd_header_tree, hf_st2110_row_num, tvb, offset, 2, ENC_BIG_ENDIAN);
offset += 2;
guint16 cont_bit = tvb_get_guint16(tvb, offset, ENC_BIG_ENDIAN) >> 15;
proto_tree_add_item(srd_header_tree, hf_st2110_continuation, tvb, offset, 2, ENC_BIG_ENDIAN);
proto_tree_add_item(srd_header_tree, hf_st2110_srd_offset, tvb, offset, 2, ENC_BIG_ENDIAN);
offset += 2;
srd_rows++;
if (cont_bit != 1) /* if continuation is not set, then no more headers*/
break;
}
PROTO_ITEM_SET_GENERATED(
proto_tree_add_uint(st2110_20_tree, hf_st2110_srd_rows, NULL, 0, 0, srd_rows)
);
/* Second pass, get SRD data and add it to the same trees created for SRD headers */
for (guint8 srd_idx = 0; srd_idx < srd_rows ; srd_idx++) {
guint16 srd_length = srd_lengths[srd_idx];
proto_tree_add_item(srd_header_trees[srd_idx], hf_st2110_srd_data, tvb, offset, srd_length, ENC_NA);
offset += srd_length;
}
col_add_fstr(pinfo->cinfo, COL_INFO, "Seq=%u, Time=%u, FirstRow=%u, Rows=%u", seqno, rtp_time, first_row, srd_rows);
return offset;
}
void
proto_register_st2110_20(void)
{
module_t *st2110_20_module;
static hf_register_info hf[] = {
{ &hf_st2110_ext_seqno,
{ "Extended Sequence Number", "st2110_20.ext_seq",
FT_UINT16, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_st2110_seqno,
{ "Sequence Number", "st2110_20.seq",
FT_UINT16, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_st2110_rtp_time,
{ "RTP Timestamp", "st2110_20.rtp_timestamp",
FT_UINT32, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_st2110_srd_index,
{ "SRD Header Index", "st2110_20.srd_index",
FT_UINT8, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_st2110_srd_length,
{ "SRD Length", "st2110_20.srd_length",
FT_UINT16, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_st2110_field_ident,
{ "Field Identification Bit", "st2110_20.srd_field_ident",
FT_UINT16, BASE_DEC, NULL, 0x8000,
NULL, HFILL }
},
{ &hf_st2110_row_num,
{ "SRD Row Number", "st2110_20.srd_row_num",
FT_UINT16, BASE_DEC, NULL, 0x7FFF,
NULL, HFILL }
},
{ &hf_st2110_continuation,
{ "SRD Continuation Bit", "st2110_20.srd_cont_bit",
FT_UINT16, BASE_DEC, NULL, 0x8000,
NULL, HFILL }
},
{ &hf_st2110_srd_offset,
{ "SRD Offset", "st2110_20.srd_offset",
FT_UINT16, BASE_DEC, NULL, 0x7FFF,
NULL, HFILL }
},
{ &hf_st2110_srd_data,
{ "SRD Data", "st2110_20.srd_data",
FT_NONE, BASE_NONE, NULL, 0x0,
NULL, HFILL }
},
{ &hf_st2110_srd_rows,
{ "SRD Rows", "st2110_20.srd_rows",
FT_UINT8, BASE_DEC, NULL, 0x0,
NULL, HFILL }
}
};
static gint *ett[] =
{
&ett_st2110_20,
&ett_st2110_20_srd_row
};
proto_st2110_20 = proto_register_protocol("SMPTE ST2110-20 (Uncompressed Active Video)", "ST2110-20", "st2110_20");
proto_register_field_array(proto_st2110_20, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
st2110_20_module = prefs_register_protocol(proto_st2110_20, NULL);
prefs_register_obsolete_preference(st2110_20_module, "dynamic.payload.type");
st2110_20_handle = register_dissector("st2110_20", dissect_st2110_20, proto_st2110_20);
}
void
proto_reg_handoff_st2110_20(void)
{
dissector_add_string("rtp_dyn_payload_type" , "ST2110-20", st2110_20_handle);
dissector_add_uint_range_with_preference("rtp.pt", "", st2110_20_handle);
proto_rtp = proto_get_id_by_filter_name("rtp");
}
/*
* Editor modelines - https://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:
*/
|
