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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-10 20:34:10 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-10 20:34:10 +0000
commite4ba6dbc3f1e76890b22773807ea37fe8fa2b1bc (patch)
tree68cb5ef9081156392f1dd62a00c6ccc1451b93df /epan/dissectors/packet-nb_rtpmux.c
parentInitial commit. (diff)
downloadwireshark-e4ba6dbc3f1e76890b22773807ea37fe8fa2b1bc.tar.xz
wireshark-e4ba6dbc3f1e76890b22773807ea37fe8fa2b1bc.zip
Adding upstream version 4.2.2.upstream/4.2.2
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'epan/dissectors/packet-nb_rtpmux.c')
-rw-r--r--epan/dissectors/packet-nb_rtpmux.c260
1 files changed, 260 insertions, 0 deletions
diff --git a/epan/dissectors/packet-nb_rtpmux.c b/epan/dissectors/packet-nb_rtpmux.c
new file mode 100644
index 00000000..3e877295
--- /dev/null
+++ b/epan/dissectors/packet-nb_rtpmux.c
@@ -0,0 +1,260 @@
+/* packet-nb_rtpmux.c
+ * Routines for 3GPP RTP Multiplex dissection, 3GPP TS 29.414
+ * Copyright 2009, ip.access ltd <amp@ipaccess.com>
+ *
+ * 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>
+
+void proto_register_nb_rtpmux(void);
+void proto_reg_handoff_nb_rtpmux(void);
+
+/* Initialize the protocol and registered fields */
+static int proto_nb_rtpmux = -1;
+static int hf_nb_rtpmux_compressed = -1;
+static int hf_nb_rtpmux_dstport = -1;
+static int hf_nb_rtpmux_length = -1;
+static int hf_nb_r_bit = -1;
+static int hf_nb_rtpmux_srcport = -1;
+static int hf_nb_rtpmux_data = -1;
+static int hf_nb_rtpmux_cmp_rtp_sequence_no = -1;
+static int hf_nb_rtpmux_cmp_rtp_timestamp = -1;
+static int hf_nb_rtpmux_cmp_rtp_data = -1;
+
+/* Initialize the subtree pointers */
+static gint ett_nb_rtpmux = -1;
+static gint ett_nb_rtpmux_cmp_rtp_hdr = -1;
+
+static dissector_handle_t nb_rtpmux_handle;
+static dissector_handle_t rtpdissector;
+
+static int
+dissect_nb_rtpmux(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
+{
+ /* Set up structures needed to add the protocol subtree and manage it */
+ proto_item *ti;
+ proto_tree *nb_rtpmux_tree, *nb_rtpmux_cmp_rtp_tree;
+ unsigned int offset = 0;
+ gboolean first_rtp_payload_seen = FALSE;
+
+ /* First, if at all possible, do some heuristics to check if the packet cannot
+ * possibly belong to your protocol. This is especially important for
+ * protocols directly on top of TCP or UDP where port collisions are
+ * common place (e.g., even though your protocol uses a well known port,
+ * someone else may set up, for example, a web server on that port which,
+ * if someone analyzed that web server's traffic in Wireshark, would result
+ * in Wireshark handing an HTTP packet to your dissector). For example:
+ */
+
+ /*
+ * XXX - this is *FAR* too weak a heuristic; it could cause all sorts
+ * of stuff to be incorrectly identified as Nb_RTPmux. Either this
+ * needs a stronger heuristic, or it needs to have a preference to
+ * set the port on which to dissect it, or it needs to be a non-heuristic
+ * dissector and *require* that a user use "Decode As..." to decode
+ * traffic as Nb_RTPmux.
+ *
+ * Look for a payload that looks like an RTP packet, using the
+ * same (weakish) heuristics as RTP uses?
+ */
+
+ /* Check that there's enough data */
+ if (tvb_captured_length(tvb) < 6)
+ return 0;
+
+ /* Make entries in Protocol column and Info column on summary display */
+ col_set_str(pinfo->cinfo, COL_PROTOCOL, "NB_RTPMUX");
+
+ /* NOTE: The offset and length values in the call to
+ "proto_tree_add_item()" define what data bytes to highlight in the hex
+ display window when the line in the protocol tree display
+ corresponding to that item is selected.
+
+ Supplying a length of -1 is the way to highlight all data from the
+ offset to the end of the packet. */
+
+ /* create display subtree for the protocol */
+ while (offset < tvb_reported_length(tvb)-5)
+ {
+ guint16 dstport, srcport;
+ unsigned int length;
+ gint captured_length;
+ tvbuff_t *next_tvb;
+ gboolean tbit;
+
+ length = tvb_get_guint8(tvb, offset+2);
+ ti = proto_tree_add_item(tree, proto_nb_rtpmux, tvb, offset, length+5, ENC_NA);
+ nb_rtpmux_tree = proto_item_add_subtree(ti, ett_nb_rtpmux);
+
+ /* T bit */
+ proto_tree_add_item(nb_rtpmux_tree, hf_nb_rtpmux_compressed, tvb, offset, 2, ENC_BIG_ENDIAN);
+ tbit = tvb_get_guint8(tvb,offset)>>7;
+ if(tbit == 1){
+ /* 6.4.2.4 Transport Format for multiplexing with RTP header compression */
+ dstport = (tvb_get_ntohs(tvb, offset) & 0x7fff) << 1;
+ proto_tree_add_uint(nb_rtpmux_tree, hf_nb_rtpmux_dstport, tvb, offset, 2, dstport );
+ proto_tree_add_item(nb_rtpmux_tree, hf_nb_rtpmux_length, tvb, offset+2, 1, ENC_BIG_ENDIAN);
+ proto_tree_add_item(nb_rtpmux_tree, hf_nb_r_bit, tvb, offset+3, 2, ENC_BIG_ENDIAN);
+ srcport = (tvb_get_ntohs(tvb, offset+3) & 0x7fff) << 1;
+ proto_tree_add_uint(nb_rtpmux_tree, hf_nb_rtpmux_srcport, tvb, offset+3, 2, srcport );
+ nb_rtpmux_cmp_rtp_tree = proto_tree_add_subtree( nb_rtpmux_tree, tvb, offset+5, 3, ett_nb_rtpmux_cmp_rtp_hdr, NULL, "Compressed RTP header" );
+ /* Sequence Number (SN) */
+ proto_tree_add_item(nb_rtpmux_cmp_rtp_tree, hf_nb_rtpmux_cmp_rtp_sequence_no, tvb, offset+5, 1, ENC_BIG_ENDIAN);
+ /* Timestamp (TS) */
+ proto_tree_add_item(nb_rtpmux_cmp_rtp_tree, hf_nb_rtpmux_cmp_rtp_timestamp, tvb, offset+6, 2, ENC_BIG_ENDIAN);
+ if (length != 0)
+ proto_tree_add_item(nb_rtpmux_cmp_rtp_tree, hf_nb_rtpmux_cmp_rtp_data,tvb, offset+8, length-3, ENC_NA);
+
+ /* Not trying to decompress... */
+
+ /* Add summary to protocol root */
+ proto_item_append_text(ti, ", Src Port: %u, Dst Port: %u Length: %u", srcport, dstport, length);
+
+ }else{
+ /* 6.4.2.3 Transport Format for multiplexing without RTP Header Compression */
+ dstport = (tvb_get_ntohs(tvb, offset) & 0x7fff) << 1;
+ proto_tree_add_uint(nb_rtpmux_tree, hf_nb_rtpmux_dstport, tvb, offset, 2, dstport );
+ proto_tree_add_item(nb_rtpmux_tree,
+ hf_nb_rtpmux_length, tvb, offset+2, 1, ENC_BIG_ENDIAN);
+ proto_tree_add_item(nb_rtpmux_tree, hf_nb_r_bit, tvb, offset+3, 1, ENC_BIG_ENDIAN);
+ srcport = (tvb_get_ntohs(tvb, offset+3) & 0x7fff) << 1;
+ proto_tree_add_uint(nb_rtpmux_tree, hf_nb_rtpmux_srcport, tvb, offset+3, 2, srcport );
+
+ /* Add summary to protocol root */
+ proto_item_append_text(ti, ", Src Port: %u, Dst Port: %u Length: %u", srcport, dstport, length);
+
+ if (length != 0)
+ {
+ /* We have an RTP payload. */
+ if (rtpdissector)
+ {
+ captured_length = tvb_reported_length_remaining(tvb, offset + 5);
+ if (captured_length > (gint)length)
+ captured_length = length;
+ next_tvb = tvb_new_subset_length_caplen(tvb, offset+5, captured_length,
+ length);
+
+ if (first_rtp_payload_seen)
+ {
+ /* Don't want to clear the column, instead show where multiple
+ RTP frames are being carried */
+ col_append_str(pinfo->cinfo, COL_INFO, " | ");
+ col_set_fence(pinfo->cinfo, COL_INFO);
+ }
+
+ call_dissector(rtpdissector, next_tvb, pinfo, nb_rtpmux_tree);
+
+ first_rtp_payload_seen = TRUE;
+ }
+ else
+ {
+ proto_tree_add_item(nb_rtpmux_tree,
+ hf_nb_rtpmux_data, tvb, offset+5, length, ENC_NA);
+ }
+ }
+ } /* if tbit */
+ offset += 5+length;
+ }
+
+ /* Return the amount of data this dissector was able to dissect */
+ return tvb_reported_length(tvb);
+}
+
+
+/* Register the protocol with Wireshark */
+
+void
+proto_register_nb_rtpmux(void)
+{
+
+ static hf_register_info hf[] = {
+ { &hf_nb_rtpmux_compressed,
+ { "Compressed headers(T bit)", "nb_rtpmux.compressed",
+ FT_BOOLEAN, 16, NULL, 0x8000,
+ NULL, HFILL }
+ },
+ { &hf_nb_rtpmux_dstport,
+ { "Dst port", "nb_rtpmux.dstport",
+ FT_UINT16, BASE_DEC, NULL, 0x0,
+ NULL, HFILL }
+ },
+ { &hf_nb_rtpmux_length,
+ { "Length", "nb_rtpmux.length",
+ FT_UINT8, BASE_DEC, NULL, 0x00,
+ NULL, HFILL }
+ },
+ { &hf_nb_r_bit,
+ { "R bit", "nb_rtpmux.r_bit",
+ FT_BOOLEAN, 16, NULL, 0x8000,
+ NULL, HFILL }
+ },
+ { &hf_nb_rtpmux_srcport,
+ { "Src port", "nb_rtpmux.srcport",
+ FT_UINT16, BASE_DEC, NULL, 0x0,
+ NULL, HFILL }
+ },
+ { &hf_nb_rtpmux_data,
+ { "RTP Packet", "nb_rtpmux.data",
+ FT_BYTES, BASE_NONE, NULL, 0x00,
+ NULL, HFILL }
+ },
+ { &hf_nb_rtpmux_cmp_rtp_sequence_no,
+ { "Sequence Number", "nb_rtpmux.cmp_rtp.sequence_no",
+ FT_UINT16, BASE_DEC, NULL, 0x00,
+ NULL, HFILL }
+ },
+ { &hf_nb_rtpmux_cmp_rtp_timestamp,
+ { "Timestamp", "nb_rtpmux.cmp_rtp.timestamp",
+ FT_UINT16, BASE_DEC, NULL, 0x00,
+ NULL, HFILL }
+ },
+ { &hf_nb_rtpmux_cmp_rtp_data,
+ { "RTP Data", "nb_rtpmux.cmp_rtp.data",
+ FT_BYTES, BASE_NONE, NULL, 0x00,
+ NULL,HFILL }
+ }
+
+ };
+
+ /* Setup protocol subtree array */
+ static gint *ett[] = {
+ &ett_nb_rtpmux,
+ &ett_nb_rtpmux_cmp_rtp_hdr
+ };
+
+ /* Register the protocol name and description */
+ proto_nb_rtpmux = proto_register_protocol("3GPP Nb Interface RTP Multiplex", "NB_RTPMUX", "nb_rtpmux");
+ nb_rtpmux_handle = register_dissector("nb_rtpmux", dissect_nb_rtpmux, proto_nb_rtpmux);
+
+ /* Required function calls to register the header fields and subtrees used */
+ proto_register_field_array(proto_nb_rtpmux, hf, array_length(hf));
+ proto_register_subtree_array(ett, array_length(ett));
+}
+
+void
+proto_reg_handoff_nb_rtpmux(void)
+{
+ dissector_add_uint_range_with_preference("udp.port", "", nb_rtpmux_handle);
+
+ rtpdissector = find_dissector_add_dependency("rtp", proto_nb_rtpmux);
+}
+
+/*
+ * 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:
+ */