diff options
author | Michael Tüxen <tuexen@fh-muenster.de> | 2012-12-27 17:11:24 +0000 |
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committer | Michael Tüxen <tuexen@fh-muenster.de> | 2012-12-27 17:11:24 +0000 |
commit | c541aa4ab52013bc0319f62bf98d2cea814e18d3 (patch) | |
tree | fd136d96a579d3ed22ed0c5ddc393c149e3bee2a /epan/dissectors/packet-rtcdc.c | |
parent | cbec3bbaf7de34fd032c4ef8de52a919aa3a0787 (diff) |
Add initial support for
http://tools.ietf.org/html/draft-jesup-rtcweb-data-protocol-03
I'll improve the dissector as the ID evolves...
svn path=/trunk/; revision=46809
Diffstat (limited to 'epan/dissectors/packet-rtcdc.c')
-rw-r--r-- | epan/dissectors/packet-rtcdc.c | 237 |
1 files changed, 237 insertions, 0 deletions
diff --git a/epan/dissectors/packet-rtcdc.c b/epan/dissectors/packet-rtcdc.c new file mode 100644 index 0000000000..843902303d --- /dev/null +++ b/epan/dissectors/packet-rtcdc.c @@ -0,0 +1,237 @@ +/* packet-rtcdc.c + * Routines for the RTCWeb Data Channel Protocol dissection + * as specified in + * http://tools.ietf.org/html/draft-jesup-rtcweb-data-protocol-03 + * + * Copyright 2012, Michael Tuexen <tuexen@wireshark.org> + * + * $Id$ + * + * 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 <glib.h> + +#include <epan/expert.h> +#include <epan/packet.h> +#include <epan/prefs.h> + +void proto_reg_handoff_rtcdc(void); + +/* PPID used for this protocol */ +static guint32 rtcdc_ppid = 50; + +/* Initialize the protocol and registered fields */ +static int proto_rtcdc = -1; +static int hf_message_type = -1; +static int hf_channel_type = -1; +static int hf_flags = -1; +static int hf_flags_reserved = -1; +static int hf_unordered_allowed = -1; +static int hf_reliability = -1; +static int hf_priority = -1; +static int hf_label = -1; +static int hf_error = -1; +static int hf_sid = -1; + +/* Initialize the subtree pointers */ +static gint ett_rtcdc = -1; +static gint ett_flags = -1; + +#define DATA_CHANNEL_OPEN_REQUEST 0x00 +#define DATA_CHANNEL_OPEN_RESPONSE 0x01 +#define DATA_CHANNEL_ACK 0x02 + +static const value_string message_type_values[] = { + { DATA_CHANNEL_OPEN_REQUEST, "DATA_CHANNEL_OPEN_REQUEST" }, + { DATA_CHANNEL_OPEN_RESPONSE, "DATA_CHANNEL_OPEN_RESPONSE" }, + { DATA_CHANNEL_ACK, "DATA_CHANNEL_ACK" }, + { 0, NULL } +}; + +#define DATA_CHANNEL_RELIABLE 0x00 +#define DATA_CHANNEL_PARTIAL_RELIABLE_REXMIT 0x01 +#define DATA_CHANNEL_PARTIAL_RELIABLE_TIMED 0x02 + +static const value_string channel_type_values[] = { + { DATA_CHANNEL_RELIABLE, "DATA_CHANNEL_RELIABLE" }, + { DATA_CHANNEL_PARTIAL_RELIABLE_REXMIT, "DATA_CHANNEL_PARTIAL_RELIABLE_REXMIT" }, + { DATA_CHANNEL_PARTIAL_RELIABLE_TIMED, "DATA_CHANNEL_PARTIAL_RELIABLE_TIMED" }, + { 0, NULL } +}; + +#define MESSAGE_TYPE_LENGTH 1 +#define CHANNEL_TYPE_LENGTH 1 +#define FLAGS_LENGTH 2 +#define RELIABILITY_LENGTH 2 +#define PRIORITY_LENGTH 2 + +#define MESSAGE_TYPE_OFFSET 0 +#define CHANNEL_TYPE_OFFSET (MESSAGE_TYPE_OFFSET + MESSAGE_TYPE_LENGTH) +#define FLAGS_OFFSET (CHANNEL_TYPE_OFFSET + CHANNEL_TYPE_LENGTH) +#define RELIABILITY_OFFSET (FLAGS_OFFSET + FLAGS_LENGTH) +#define PRIORITY_OFFSET (RELIABILITY_OFFSET + RELIABILITY_LENGTH) +#define LABEL_OFFSET (PRIORITY_OFFSET + PRIORITY_LENGTH) + +#define DATA_CHANNEL_FLAG_OUT_OF_ORDER_ALLOWED_MASK 0x0001 +#define DATA_CHANNEL_FLAG_RESERVED_MASK 0xFFFE + +static void +dissect_open_request_message(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *rtcdc_tree, proto_item *rtcdc_item _U_) { + if (rtcdc_tree) { + proto_tree *flags_tree; + proto_item *flags_item; + + proto_tree_add_item(rtcdc_tree, hf_channel_type, tvb, CHANNEL_TYPE_OFFSET, CHANNEL_TYPE_LENGTH, ENC_BIG_ENDIAN); + flags_item = proto_tree_add_item(rtcdc_tree, hf_flags, tvb, FLAGS_OFFSET, FLAGS_LENGTH, ENC_BIG_ENDIAN); + flags_tree = proto_item_add_subtree(flags_item, ett_flags); + proto_tree_add_item(flags_tree, hf_flags_reserved, tvb, FLAGS_OFFSET, FLAGS_LENGTH, ENC_BIG_ENDIAN); + proto_tree_add_item(flags_tree, hf_unordered_allowed, tvb, FLAGS_OFFSET, FLAGS_LENGTH, ENC_BIG_ENDIAN); + proto_tree_add_item(rtcdc_tree, hf_reliability, tvb, RELIABILITY_OFFSET, RELIABILITY_LENGTH, ENC_BIG_ENDIAN); + proto_tree_add_item(rtcdc_tree, hf_priority, tvb, PRIORITY_OFFSET, PRIORITY_LENGTH, ENC_BIG_ENDIAN); + proto_tree_add_item(rtcdc_tree, hf_label, tvb, LABEL_OFFSET, -1, ENC_BIG_ENDIAN); + } + return; +} + +#define ERROR_LENGTH 1 +#define SID_LENGTH 2 +#define DATA_CHANNEL_RESPONSE_LENGTH (MESSAGE_TYPE_LENGTH + ERROR_LENGTH + FLAGS_LENGTH + SID_LENGTH) + +#define ERROR_OFFSET (MESSAGE_TYPE_OFFSET + MESSAGE_TYPE_LENGTH) +#define SID_OFFSET (FLAGS_OFFSET + FLAGS_LENGTH) + +static void +dissect_open_response_message(tvbuff_t *tvb, packet_info *pinfo, proto_tree *rtcdc_tree, proto_item *rtcdc_item) { + if (tvb_length(tvb) > DATA_CHANNEL_RESPONSE_LENGTH) { + expert_add_info_format(pinfo, rtcdc_item, PI_MALFORMED, PI_ERROR, "Message too long"); + } + if (rtcdc_tree) { + proto_tree_add_item(rtcdc_tree, hf_error, tvb, ERROR_OFFSET, ERROR_LENGTH, ENC_BIG_ENDIAN); + proto_tree_add_item(rtcdc_tree, hf_flags, tvb, FLAGS_OFFSET, FLAGS_LENGTH, ENC_BIG_ENDIAN); + proto_tree_add_item(rtcdc_tree, hf_sid, tvb, SID_OFFSET, SID_LENGTH, ENC_BIG_ENDIAN); + } + return; +} + +#define DATA_CHANNEL_ACK_LENGTH MESSAGE_TYPE_LENGTH + +static void +dissect_open_ack_message(tvbuff_t *tvb, packet_info *pinfo, proto_tree *rtcdc_tree _U_, proto_item *rtcdc_item) { + if (tvb_length(tvb) > DATA_CHANNEL_ACK_LENGTH) { + expert_add_info_format(pinfo, rtcdc_item, PI_MALFORMED, PI_ERROR, "Message too long"); + } + return; +} + +static int +dissect_rtcdc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_) +{ + proto_item *rtcdc_item; + proto_tree *rtcdc_tree; + guint8 message_type; + + message_type = tvb_get_guint8(tvb, MESSAGE_TYPE_OFFSET); + + col_set_str(pinfo->cinfo, COL_PROTOCOL, "RTCDC"); + col_add_fstr(pinfo->cinfo, COL_INFO, "%s ", val_to_str_const(message_type, message_type_values, "reserved")); + if (tree) { + rtcdc_item = proto_tree_add_item(tree, proto_rtcdc, tvb, 0, -1, ENC_NA); + rtcdc_tree = proto_item_add_subtree(rtcdc_item, ett_rtcdc); + proto_tree_add_item(rtcdc_tree, hf_message_type, tvb, MESSAGE_TYPE_OFFSET, MESSAGE_TYPE_LENGTH, ENC_BIG_ENDIAN); + } else { + rtcdc_item = NULL; + rtcdc_tree = NULL; + } + switch (message_type) { + case DATA_CHANNEL_OPEN_REQUEST: + dissect_open_request_message(tvb, pinfo, rtcdc_tree, rtcdc_item); + break; + case DATA_CHANNEL_OPEN_RESPONSE: + dissect_open_response_message(tvb, pinfo, rtcdc_tree, rtcdc_item); + break; + case DATA_CHANNEL_ACK: + dissect_open_ack_message(tvb, pinfo, rtcdc_tree, rtcdc_item); + break; + default: + expert_add_info_format(pinfo, rtcdc_item, PI_MALFORMED, PI_ERROR, "Unknown message type"); + break; + } + return tvb_length(tvb); +} + +void +proto_register_rtcdc(void) +{ + module_t *rtcdc_module; + static hf_register_info hf[] = { + { &hf_message_type, { "Message type", "rtcdc.message_type", FT_UINT8, BASE_DEC, VALS(message_type_values), 0x0, NULL, HFILL } }, + { &hf_channel_type, { "Channel type", "rtcdc.channel_type", FT_UINT8, BASE_DEC, VALS(channel_type_values), 0x0, NULL, HFILL } }, + { &hf_flags, { "Flags", "rtcdc.flags", FT_UINT16, BASE_HEX, NULL, 0x0, NULL, HFILL } }, + { &hf_flags_reserved, { "Reserved", "rtcdc.flags_reserved", FT_UINT16, BASE_HEX, NULL, DATA_CHANNEL_FLAG_RESERVED_MASK, NULL, HFILL } }, + { &hf_unordered_allowed, { "Unordered allowed", "rtcdc.flags_unordered_allowed", FT_BOOLEAN, 16, NULL, DATA_CHANNEL_FLAG_OUT_OF_ORDER_ALLOWED_MASK, NULL, HFILL } }, + { &hf_reliability, { "Reliability parameter", "rtcdc.reliability_parameter", FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL } }, + { &hf_priority, { "Priority", "rtcdc.priority", FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL } }, + { &hf_label, { "Label", "rtcdc.label", FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL } }, + { &hf_error, { "Error", "rtcdc.error", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL } }, + { &hf_sid, { "Reverse stream identifier", "rtcdc.reverse_stream_id", FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL } } + }; + static gint *ett[] = { + &ett_rtcdc, + &ett_flags + }; + + proto_rtcdc = proto_register_protocol("WebRTC Datachannel Protocol", "RTCDC", "rtcdc"); + proto_register_field_array(proto_rtcdc, hf, array_length(hf)); + proto_register_subtree_array(ett, array_length(ett)); + rtcdc_module = prefs_register_protocol(proto_rtcdc, proto_reg_handoff_rtcdc); + prefs_register_uint_preference(rtcdc_module, "sctp.ppi", "RTCDC SCTP PPID", "RTCDC SCTP PPID if other than the default", 10, &rtcdc_ppid); +} + +void +proto_reg_handoff_rtcdc(void) +{ + static gboolean initialized = FALSE; + static dissector_handle_t rtcdc_handle; + static guint32 current_ppid; + + if (!initialized) { + rtcdc_handle = new_create_dissector_handle(dissect_rtcdc, proto_rtcdc); + initialized = TRUE; + } else { + dissector_delete_uint("sctp.ppi", current_ppid, rtcdc_handle); + } + current_ppid = rtcdc_ppid; + dissector_add_uint("sctp.ppi", current_ppid, rtcdc_handle); +} + +/* + * 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: + */ |