forked from osmocom/wireshark
d47551982b
Mirror it after protocol dissector API. Change-Id: I7985bcfa9e07654c7cf005efec94efc205d7a304 Reviewed-on: https://code.wireshark.org/review/18496 Reviewed-by: Michael Mann <mmann78@netscape.net>
1297 lines
48 KiB
C
1297 lines
48 KiB
C
/* packet-udp.c
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* Routines for UDP/UDP-Lite packet disassembly
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*
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* Wireshark - Network traffic analyzer
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* By Gerald Combs <gerald@wireshark.org>
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* Copyright 1998 Gerald Combs
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*
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* Richard Sharpe, 13-Feb-1999, added dispatch table support and
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* support for tftp.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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*/
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#define NEW_PROTO_TREE_API
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#include "config.h"
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#include <epan/packet.h>
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#include <epan/capture_dissectors.h>
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#include <epan/addr_resolv.h>
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#include <epan/ipproto.h>
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#include <epan/in_cksum.h>
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#include <epan/prefs.h>
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#include <epan/follow.h>
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#include <epan/expert.h>
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#include <epan/exceptions.h>
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#include <epan/show_exception.h>
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#include <epan/proto_data.h>
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#include <wsutil/utf8_entities.h>
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#include <wsutil/pint.h>
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#include "packet-udp.h"
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#include <epan/conversation.h>
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#include <epan/conversation_table.h>
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#include <epan/dissector_filters.h>
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#include <epan/exported_pdu.h>
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#include <epan/decode_as.h>
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void proto_register_udp(void);
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void proto_reg_handoff_udp(void);
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static dissector_handle_t udp_handle;
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static dissector_handle_t udplite_handle;
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static int udp_tap = -1;
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static int udp_follow_tap = -1;
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static int exported_pdu_tap = -1;
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static header_field_info *hfi_udp = NULL;
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static header_field_info *hfi_udplite = NULL;
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#define UDP_HFI_INIT HFI_INIT(proto_udp)
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#define UDPLITE_HFI_INIT HFI_INIT(proto_udplite)
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static header_field_info hfi_udp_srcport UDP_HFI_INIT =
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{ "Source Port", "udp.srcport", FT_UINT16, BASE_PT_UDP, NULL, 0x0,
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NULL, HFILL };
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static header_field_info hfi_udp_dstport UDP_HFI_INIT =
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{ "Destination Port", "udp.dstport", FT_UINT16, BASE_PT_UDP, NULL, 0x0,
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NULL, HFILL };
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static header_field_info hfi_udp_port UDP_HFI_INIT =
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{ "Source or Destination Port", "udp.port", FT_UINT16, BASE_PT_UDP, NULL, 0x0,
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NULL, HFILL };
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static header_field_info hfi_udp_stream UDP_HFI_INIT =
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{ "Stream index", "udp.stream", FT_UINT32, BASE_DEC, NULL, 0x0,
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NULL, HFILL };
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static header_field_info hfi_udp_length UDP_HFI_INIT =
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{ "Length", "udp.length", FT_UINT16, BASE_DEC, NULL, 0x0,
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NULL, HFILL };
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static header_field_info hfi_udp_checksum UDP_HFI_INIT =
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{ "Checksum", "udp.checksum", FT_UINT16, BASE_HEX, NULL, 0x0,
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"Details at: http://www.wireshark.org/docs/wsug_html_chunked/ChAdvChecksums.html", HFILL };
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static header_field_info hfi_udp_checksum_calculated UDP_HFI_INIT =
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{ "Calculated Checksum", "udp.checksum_calculated", FT_UINT16, BASE_HEX, NULL, 0x0,
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"The expected UDP checksum field as calculated from the UDP packet", HFILL };
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static header_field_info hfi_udp_checksum_status UDP_HFI_INIT =
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{ "Checksum Status", "udp.checksum.status", FT_UINT8, BASE_NONE, VALS(proto_checksum_vals), 0x0,
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NULL, HFILL };
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static header_field_info hfi_udp_proc_src_uid UDP_HFI_INIT =
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{ "Source process user ID", "udp.proc.srcuid", FT_UINT32, BASE_DEC, NULL, 0x0,
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NULL, HFILL};
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static header_field_info hfi_udp_proc_src_pid UDP_HFI_INIT =
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{ "Source process ID", "udp.proc.srcpid", FT_UINT32, BASE_DEC, NULL, 0x0,
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NULL, HFILL};
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static header_field_info hfi_udp_proc_src_uname UDP_HFI_INIT =
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{ "Source process user name", "udp.proc.srcuname", FT_STRING, BASE_NONE, NULL, 0x0,
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NULL, HFILL};
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static header_field_info hfi_udp_proc_src_cmd UDP_HFI_INIT =
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{ "Source process name", "udp.proc.srccmd", FT_STRING, BASE_NONE, NULL, 0x0,
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"Source process command name", HFILL};
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static header_field_info hfi_udp_proc_dst_uid UDP_HFI_INIT =
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{ "Destination process user ID", "udp.proc.dstuid", FT_UINT32, BASE_DEC, NULL, 0x0,
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NULL, HFILL};
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static header_field_info hfi_udp_proc_dst_pid UDP_HFI_INIT =
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{ "Destination process ID", "udp.proc.dstpid", FT_UINT32, BASE_DEC, NULL, 0x0,
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NULL, HFILL};
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static header_field_info hfi_udp_proc_dst_uname UDP_HFI_INIT =
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{ "Destination process user name", "udp.proc.dstuname", FT_STRING, BASE_NONE, NULL, 0x0,
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NULL, HFILL};
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static header_field_info hfi_udp_proc_dst_cmd UDP_HFI_INIT =
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{ "Destination process name", "udp.proc.dstcmd", FT_STRING, BASE_NONE, NULL, 0x0,
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"Destination process command name", HFILL};
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static header_field_info hfi_udp_pdu_size UDP_HFI_INIT =
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{ "PDU Size", "udp.pdu.size", FT_UINT32, BASE_DEC, NULL, 0x0,
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"The size of this PDU", HFILL };
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static header_field_info hfi_udplite_checksum_coverage UDPLITE_HFI_INIT =
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{ "Checksum coverage", "udp.checksum_coverage", FT_UINT16, BASE_DEC, NULL, 0x0,
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NULL, HFILL };
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static gint ett_udp = -1;
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static gint ett_udp_checksum = -1;
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static gint ett_udp_process_info = -1;
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static expert_field ei_udp_possible_traceroute = EI_INIT;
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static expert_field ei_udp_length_bad = EI_INIT;
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static expert_field ei_udplite_checksum_coverage_bad = EI_INIT;
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static expert_field ei_udp_checksum_zero = EI_INIT;
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static expert_field ei_udp_checksum_bad = EI_INIT;
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static expert_field ei_udp_length_bad_zero = EI_INIT;
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/* Preferences */
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/* Place UDP summary in proto tree */
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static gboolean udp_summary_in_tree = TRUE;
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/* Check UDP checksums */
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static gboolean udp_check_checksum = FALSE;
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/* Collect IPFIX process flow information */
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static gboolean udp_process_info = FALSE;
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/* Ignore an invalid checksum coverage field for UDP-Lite */
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static gboolean udplite_ignore_checksum_coverage = TRUE;
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/* Check UDP-Lite checksums */
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static gboolean udplite_check_checksum = FALSE;
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static dissector_table_t udp_dissector_table;
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static heur_dissector_list_t heur_subdissector_list;
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static guint32 udp_stream_count;
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/* Determine if there is a sub-dissector and call it. This has been */
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/* separated into a stand alone routine so other protocol dissectors */
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/* can call to it, ie. socks */
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static gboolean try_heuristic_first = FALSE;
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/* Per-packet-info for UDP */
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typedef struct
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{
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heur_dtbl_entry_t *heur_dtbl_entry;
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} udp_p_info_t;
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static void
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udp_src_prompt(packet_info *pinfo, gchar *result)
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{
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g_snprintf(result, MAX_DECODE_AS_PROMPT_LEN, "source (%u%s)", pinfo->srcport, UTF8_RIGHTWARDS_ARROW);
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}
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static gpointer
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udp_src_value(packet_info *pinfo)
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{
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return GUINT_TO_POINTER(pinfo->srcport);
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}
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static void
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udp_dst_prompt(packet_info *pinfo, gchar *result)
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{
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g_snprintf(result, MAX_DECODE_AS_PROMPT_LEN, "destination (%s%u)", UTF8_RIGHTWARDS_ARROW, pinfo->destport);
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}
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static gpointer
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udp_dst_value(packet_info *pinfo)
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{
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return GUINT_TO_POINTER(pinfo->destport);
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}
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static void
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udp_both_prompt(packet_info *pinfo, gchar *result)
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{
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g_snprintf(result, MAX_DECODE_AS_PROMPT_LEN, "Both (%u%s%u)", pinfo->srcport, UTF8_LEFT_RIGHT_ARROW, pinfo->destport);
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}
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/* Conversation and process code originally copied from packet-tcp.c */
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static struct udp_analysis *
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init_udp_conversation_data(void)
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{
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struct udp_analysis *udpd;
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/* Initialize the udp protocol data structure to add to the udp conversation */
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udpd = wmem_new0(wmem_file_scope(), struct udp_analysis);
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/*
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udpd->flow1.username = NULL;
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udpd->flow1.command = NULL;
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udpd->flow2.username = NULL;
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udpd->flow2.command = NULL;
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*/
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udpd->stream = udp_stream_count++;
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return udpd;
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}
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struct udp_analysis *
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get_udp_conversation_data(conversation_t *conv, packet_info *pinfo)
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{
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int direction;
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struct udp_analysis *udpd=NULL;
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/* Did the caller supply the conversation pointer? */
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if (conv == NULL)
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conv = find_or_create_conversation(pinfo);
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/* Get the data for this conversation */
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udpd=(struct udp_analysis *)conversation_get_proto_data(conv, hfi_udp->id);
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/* If the conversation was just created or it matched a
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* conversation with template options, udpd will not
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* have been initialized. So, initialize
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* a new udpd structure for the conversation.
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*/
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if (!udpd) {
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udpd = init_udp_conversation_data();
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conversation_add_proto_data(conv, hfi_udp->id, udpd);
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}
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if (!udpd) {
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return NULL;
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}
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/* check direction and get ua lists */
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direction=cmp_address(&pinfo->src, &pinfo->dst);
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/* if the addresses are equal, match the ports instead */
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if (direction == 0) {
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direction= (pinfo->srcport > pinfo->destport) ? 1 : -1;
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}
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if (direction >= 0) {
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udpd->fwd=&(udpd->flow1);
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udpd->rev=&(udpd->flow2);
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} else {
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udpd->fwd=&(udpd->flow2);
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udpd->rev=&(udpd->flow1);
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}
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return udpd;
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}
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static const char* udp_conv_get_filter_type(conv_item_t* conv, conv_filter_type_e filter)
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{
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if (filter == CONV_FT_SRC_PORT)
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return "udp.srcport";
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if (filter == CONV_FT_DST_PORT)
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return "udp.dstport";
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if (filter == CONV_FT_ANY_PORT)
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return "udp.port";
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if(!conv) {
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return CONV_FILTER_INVALID;
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}
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if (filter == CONV_FT_SRC_ADDRESS) {
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if (conv->src_address.type == AT_IPv4)
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return "ip.src";
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if (conv->src_address.type == AT_IPv6)
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return "ipv6.src";
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}
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if (filter == CONV_FT_DST_ADDRESS) {
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if (conv->dst_address.type == AT_IPv4)
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return "ip.dst";
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if (conv->dst_address.type == AT_IPv6)
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return "ipv6.dst";
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}
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if (filter == CONV_FT_ANY_ADDRESS) {
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if (conv->src_address.type == AT_IPv4)
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return "ip.addr";
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if (conv->src_address.type == AT_IPv6)
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return "ipv6.addr";
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}
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return CONV_FILTER_INVALID;
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}
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static ct_dissector_info_t udp_ct_dissector_info = {&udp_conv_get_filter_type};
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static int
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udpip_conversation_packet(void *pct, packet_info *pinfo, epan_dissect_t *edt _U_, const void *vip)
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{
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conv_hash_t *hash = (conv_hash_t*) pct;
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const e_udphdr *udphdr=(const e_udphdr *)vip;
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add_conversation_table_data_with_conv_id(hash, &udphdr->ip_src, &udphdr->ip_dst, udphdr->uh_sport, udphdr->uh_dport, (conv_id_t) udphdr->uh_stream, 1, pinfo->fd->pkt_len, &pinfo->rel_ts, &pinfo->abs_ts, &udp_ct_dissector_info, PT_UDP);
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return 1;
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}
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static const char* udp_host_get_filter_type(hostlist_talker_t* host, conv_filter_type_e filter)
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{
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if (filter == CONV_FT_SRC_PORT)
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return "udp.srcport";
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if (filter == CONV_FT_DST_PORT)
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return "udp.dstport";
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if (filter == CONV_FT_ANY_PORT)
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return "udp.port";
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if(!host) {
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return CONV_FILTER_INVALID;
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}
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if (filter == CONV_FT_SRC_ADDRESS || filter == CONV_FT_DST_ADDRESS || filter == CONV_FT_ANY_ADDRESS) {
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if (host->myaddress.type == AT_IPv4)
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return "ip.src";
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if (host->myaddress.type == AT_IPv6)
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return "ipv6.src";
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}
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return CONV_FILTER_INVALID;
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}
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static hostlist_dissector_info_t udp_host_dissector_info = {&udp_host_get_filter_type};
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static int
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udpip_hostlist_packet(void *pit, packet_info *pinfo, epan_dissect_t *edt _U_, const void *vip)
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{
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conv_hash_t *hash = (conv_hash_t*) pit;
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const e_udphdr *udphdr=(const e_udphdr *)vip;
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/* Take two "add" passes per packet, adding for each direction, ensures that all
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packets are counted properly (even if address is sending to itself)
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XXX - this could probably be done more efficiently inside hostlist_table */
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add_hostlist_table_data(hash, &udphdr->ip_src, udphdr->uh_sport, TRUE, 1, pinfo->fd->pkt_len, &udp_host_dissector_info, PT_UDP);
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add_hostlist_table_data(hash, &udphdr->ip_dst, udphdr->uh_dport, FALSE, 1, pinfo->fd->pkt_len, &udp_host_dissector_info, PT_UDP);
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return 1;
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}
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static gboolean
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udp_filter_valid(packet_info *pinfo)
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{
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return proto_is_frame_protocol(pinfo->layers, "udp");
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}
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static gchar*
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udp_build_filter(packet_info *pinfo)
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{
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if( pinfo->net_src.type == AT_IPv4 && pinfo->net_dst.type == AT_IPv4 ) {
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/* UDP over IPv4 */
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return g_strdup_printf("(ip.addr eq %s and ip.addr eq %s) and (udp.port eq %d and udp.port eq %d)",
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address_to_str(pinfo->pool, &pinfo->net_src),
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address_to_str(pinfo->pool, &pinfo->net_dst),
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pinfo->srcport, pinfo->destport );
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}
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if( pinfo->net_src.type == AT_IPv6 && pinfo->net_dst.type == AT_IPv6 ) {
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/* UDP over IPv6 */
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return g_strdup_printf("(ipv6.addr eq %s and ipv6.addr eq %s) and (udp.port eq %d and udp.port eq %d)",
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address_to_str(pinfo->pool, &pinfo->net_src),
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address_to_str(pinfo->pool, &pinfo->net_dst),
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pinfo->srcport, pinfo->destport );
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}
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return NULL;
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}
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static gchar* udp_follow_conv_filter(packet_info *pinfo, int* stream)
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{
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conversation_t *conv;
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struct udp_analysis *udpd;
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if( ((pinfo->net_src.type == AT_IPv4 && pinfo->net_dst.type == AT_IPv4) ||
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(pinfo->net_src.type == AT_IPv6 && pinfo->net_dst.type == AT_IPv6))
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&& (conv=find_conversation(pinfo->num, &pinfo->src, &pinfo->dst, pinfo->ptype,
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pinfo->srcport, pinfo->destport, 0)) != NULL )
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{
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/* UDP over IPv4/6 */
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udpd=get_udp_conversation_data(conv, pinfo);
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if (udpd == NULL)
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return NULL;
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*stream = udpd->stream;
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return g_strdup_printf("udp.stream eq %d", udpd->stream);
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}
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return NULL;
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}
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static gchar* udp_follow_index_filter(int stream)
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{
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return g_strdup_printf("udp.stream eq %d", stream);
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}
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static gchar* udp_follow_address_filter(address* src_addr, address* dst_addr, int src_port, int dst_port)
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{
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const gchar *ip_version = src_addr->type == AT_IPv6 ? "v6" : "";
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gchar src_addr_str[MAX_IP6_STR_LEN];
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gchar dst_addr_str[MAX_IP6_STR_LEN];
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address_to_str_buf(src_addr, src_addr_str, sizeof(src_addr_str));
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address_to_str_buf(dst_addr, dst_addr_str, sizeof(dst_addr_str));
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return g_strdup_printf("((ip%s.src eq %s and udp.srcport eq %d) and "
|
|
"(ip%s.dst eq %s and udp.dstport eq %d))"
|
|
" or "
|
|
"((ip%s.src eq %s and udp.srcport eq %d) and "
|
|
"(ip%s.dst eq %s and udp.dstport eq %d))",
|
|
ip_version, src_addr_str, src_port,
|
|
ip_version, dst_addr_str, dst_port,
|
|
ip_version, dst_addr_str, dst_port,
|
|
ip_version, src_addr_str, src_port);
|
|
}
|
|
|
|
|
|
/* Attach process info to a flow */
|
|
/* XXX - We depend on the UDP dissector finding the conversation first */
|
|
void
|
|
add_udp_process_info(guint32 frame_num, address *local_addr, address *remote_addr, guint16 local_port, guint16 remote_port, guint32 uid, guint32 pid, gchar *username, gchar *command) {
|
|
conversation_t *conv;
|
|
struct udp_analysis *udpd;
|
|
udp_flow_t *flow = NULL;
|
|
|
|
if (!udp_process_info) {
|
|
return;
|
|
}
|
|
|
|
conv = find_conversation(frame_num, local_addr, remote_addr, PT_UDP, local_port, remote_port, 0);
|
|
if (!conv) {
|
|
return;
|
|
}
|
|
|
|
udpd = (struct udp_analysis *)conversation_get_proto_data(conv, hfi_udp->id);
|
|
if (!udpd) {
|
|
return;
|
|
}
|
|
|
|
if ((cmp_address(local_addr, &conv->key_ptr->addr1) == 0) && (local_port == conv->key_ptr->port1)) {
|
|
flow = &udpd->flow1;
|
|
} else if ((cmp_address(remote_addr, &conv->key_ptr->addr1) == 0) && (remote_port == conv->key_ptr->port1)) {
|
|
flow = &udpd->flow2;
|
|
}
|
|
if (!flow || flow->command) {
|
|
return;
|
|
}
|
|
|
|
flow->process_uid = uid;
|
|
flow->process_pid = pid;
|
|
flow->username = wmem_strdup(wmem_file_scope(), username);
|
|
flow->command = wmem_strdup(wmem_file_scope(), command);
|
|
}
|
|
|
|
|
|
/* Return the current stream count */
|
|
guint32 get_udp_stream_count(void)
|
|
{
|
|
return udp_stream_count;
|
|
}
|
|
|
|
static void
|
|
handle_export_pdu_dissection_table(packet_info *pinfo, tvbuff_t *tvb, guint32 port)
|
|
{
|
|
if (have_tap_listener(exported_pdu_tap)) {
|
|
exp_pdu_data_item_t exp_pdu_data_table_value = {exp_pdu_data_dissector_table_num_value_size, exp_pdu_data_dissector_table_num_value_populate_data, NULL};
|
|
|
|
const exp_pdu_data_item_t *udp_exp_pdu_items[] = {
|
|
&exp_pdu_data_src_ip,
|
|
&exp_pdu_data_dst_ip,
|
|
&exp_pdu_data_port_type,
|
|
&exp_pdu_data_src_port,
|
|
&exp_pdu_data_dst_port,
|
|
&exp_pdu_data_orig_frame_num,
|
|
&exp_pdu_data_table_value,
|
|
NULL
|
|
};
|
|
|
|
exp_pdu_data_t *exp_pdu_data;
|
|
|
|
exp_pdu_data_table_value.data = GUINT_TO_POINTER(port);
|
|
|
|
exp_pdu_data = export_pdu_create_tags(pinfo, "udp.port", EXP_PDU_TAG_DISSECTOR_TABLE_NAME, udp_exp_pdu_items);
|
|
exp_pdu_data->tvb_captured_length = tvb_captured_length(tvb);
|
|
exp_pdu_data->tvb_reported_length = tvb_reported_length(tvb);
|
|
exp_pdu_data->pdu_tvb = tvb;
|
|
|
|
tap_queue_packet(exported_pdu_tap, pinfo, exp_pdu_data);
|
|
}
|
|
}
|
|
|
|
static void
|
|
handle_export_pdu_heuristic(packet_info *pinfo, tvbuff_t *tvb, heur_dtbl_entry_t *hdtbl_entry)
|
|
{
|
|
exp_pdu_data_t *exp_pdu_data = NULL;
|
|
|
|
if (have_tap_listener(exported_pdu_tap)) {
|
|
if ((!hdtbl_entry->enabled) ||
|
|
(hdtbl_entry->protocol != NULL && !proto_is_protocol_enabled(hdtbl_entry->protocol))) {
|
|
exp_pdu_data = export_pdu_create_common_tags(pinfo, "data", EXP_PDU_TAG_PROTO_NAME);
|
|
} else if (hdtbl_entry->protocol != NULL) {
|
|
exp_pdu_data = export_pdu_create_common_tags(pinfo, hdtbl_entry->short_name, EXP_PDU_TAG_HEUR_PROTO_NAME);
|
|
}
|
|
|
|
if (exp_pdu_data != NULL) {
|
|
exp_pdu_data->tvb_captured_length = tvb_captured_length(tvb);
|
|
exp_pdu_data->tvb_reported_length = tvb_reported_length(tvb);
|
|
exp_pdu_data->pdu_tvb = tvb;
|
|
|
|
tap_queue_packet(exported_pdu_tap, pinfo, exp_pdu_data);
|
|
}
|
|
}
|
|
}
|
|
|
|
static void
|
|
handle_export_pdu_conversation(packet_info *pinfo, tvbuff_t *tvb, int uh_dport, int uh_sport)
|
|
{
|
|
if (have_tap_listener(exported_pdu_tap)) {
|
|
conversation_t *conversation = find_conversation(pinfo->num, &pinfo->dst, &pinfo->src, PT_UDP, uh_dport, uh_sport, 0);
|
|
if (conversation != NULL)
|
|
{
|
|
dissector_handle_t handle = (dissector_handle_t)wmem_tree_lookup32_le(conversation->dissector_tree, pinfo->num);
|
|
if (handle != NULL)
|
|
{
|
|
exp_pdu_data_t *exp_pdu_data = export_pdu_create_common_tags(pinfo, dissector_handle_get_dissector_name(handle), EXP_PDU_TAG_PROTO_NAME);
|
|
exp_pdu_data->tvb_captured_length = tvb_captured_length(tvb);
|
|
exp_pdu_data->tvb_reported_length = tvb_reported_length(tvb);
|
|
exp_pdu_data->pdu_tvb = tvb;
|
|
|
|
tap_queue_packet(exported_pdu_tap, pinfo, exp_pdu_data);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
void
|
|
decode_udp_ports(tvbuff_t *tvb, int offset, packet_info *pinfo,
|
|
proto_tree *tree, int uh_sport, int uh_dport, int uh_ulen)
|
|
{
|
|
tvbuff_t *next_tvb;
|
|
int low_port, high_port;
|
|
gint len, reported_len;
|
|
udp_p_info_t *udp_p_info = NULL;
|
|
/* Save curr_layer_num as it might be changed by subdissector */
|
|
guint8 curr_layer_num = pinfo->curr_layer_num;
|
|
heur_dtbl_entry_t *hdtbl_entry;
|
|
exp_pdu_data_t *exp_pdu_data;
|
|
|
|
len = tvb_captured_length_remaining(tvb, offset);
|
|
reported_len = tvb_reported_length_remaining(tvb, offset);
|
|
if (uh_ulen != -1) {
|
|
/* This is the length from the UDP header; the payload should be cut
|
|
off at that length. (If our caller passed a value here, they
|
|
are assumed to have checked that it's >= 8, and hence >= offset.)
|
|
|
|
XXX - what if it's *greater* than the reported length? */
|
|
if ((uh_ulen - offset) < reported_len)
|
|
reported_len = uh_ulen - offset;
|
|
if (len > reported_len)
|
|
len = reported_len;
|
|
}
|
|
|
|
next_tvb = tvb_new_subset(tvb, offset, len, reported_len);
|
|
|
|
/* If the user has a "Follow UDP Stream" window loading, pass a pointer
|
|
* to the payload tvb through the tap system. */
|
|
if (have_tap_listener(udp_follow_tap))
|
|
tap_queue_packet(udp_follow_tap, pinfo, next_tvb);
|
|
|
|
if (pinfo->fd->flags.visited) {
|
|
udp_p_info = (udp_p_info_t*)p_get_proto_data(wmem_file_scope(), pinfo, hfi_udp->id, pinfo->curr_layer_num);
|
|
if (udp_p_info) {
|
|
call_heur_dissector_direct(udp_p_info->heur_dtbl_entry, next_tvb, pinfo, tree, NULL);
|
|
handle_export_pdu_heuristic(pinfo, next_tvb, udp_p_info->heur_dtbl_entry);
|
|
return;
|
|
}
|
|
}
|
|
|
|
/* determine if this packet is part of a conversation and call dissector */
|
|
/* for the conversation if available */
|
|
if (try_conversation_dissector(&pinfo->dst, &pinfo->src, PT_UDP,
|
|
uh_dport, uh_sport, next_tvb, pinfo, tree, NULL)) {
|
|
handle_export_pdu_conversation(pinfo, next_tvb, uh_dport, uh_sport);
|
|
return;
|
|
}
|
|
|
|
if (try_heuristic_first) {
|
|
/* Do lookup with the heuristic subdissector table */
|
|
if (dissector_try_heuristic(heur_subdissector_list, next_tvb, pinfo, tree, &hdtbl_entry, NULL)) {
|
|
if (!udp_p_info) {
|
|
udp_p_info = wmem_new0(wmem_file_scope(), udp_p_info_t);
|
|
udp_p_info->heur_dtbl_entry = hdtbl_entry;
|
|
p_add_proto_data(wmem_file_scope(), pinfo, hfi_udp->id, curr_layer_num, udp_p_info);
|
|
}
|
|
|
|
handle_export_pdu_heuristic(pinfo, next_tvb, udp_p_info->heur_dtbl_entry);
|
|
return;
|
|
}
|
|
}
|
|
|
|
/* Do lookups with the subdissector table.
|
|
We try the port number with the lower value first, followed by the
|
|
port number with the higher value. This means that, for packets
|
|
where a dissector is registered for *both* port numbers:
|
|
|
|
1) we pick the same dissector for traffic going in both directions;
|
|
|
|
2) we prefer the port number that's more likely to be the right
|
|
one (as that prefers well-known ports to reserved ports);
|
|
|
|
although there is, of course, no guarantee that any such strategy
|
|
will always pick the right port number.
|
|
|
|
XXX - we ignore port numbers of 0, as some dissectors use a port
|
|
number of 0 to disable the port, and as RFC 768 says that the source
|
|
port in UDP datagrams is optional and is 0 if not used. */
|
|
if (uh_sport > uh_dport) {
|
|
low_port = uh_dport;
|
|
high_port = uh_sport;
|
|
} else {
|
|
low_port = uh_sport;
|
|
high_port = uh_dport;
|
|
}
|
|
if ((low_port != 0) &&
|
|
dissector_try_uint(udp_dissector_table, low_port, next_tvb, pinfo, tree)) {
|
|
handle_export_pdu_dissection_table(pinfo, next_tvb, low_port);
|
|
return;
|
|
}
|
|
if ((high_port != 0) &&
|
|
dissector_try_uint(udp_dissector_table, high_port, next_tvb, pinfo, tree)) {
|
|
handle_export_pdu_dissection_table(pinfo, next_tvb, high_port);
|
|
return;
|
|
}
|
|
|
|
if (!try_heuristic_first) {
|
|
/* Do lookup with the heuristic subdissector table */
|
|
if (dissector_try_heuristic(heur_subdissector_list, next_tvb, pinfo, tree, &hdtbl_entry, NULL)) {
|
|
if (!udp_p_info) {
|
|
udp_p_info = wmem_new0(wmem_file_scope(), udp_p_info_t);
|
|
udp_p_info->heur_dtbl_entry = hdtbl_entry;
|
|
p_add_proto_data(wmem_file_scope(), pinfo, hfi_udp->id, curr_layer_num, udp_p_info);
|
|
}
|
|
|
|
handle_export_pdu_heuristic(pinfo, next_tvb, udp_p_info->heur_dtbl_entry);
|
|
return;
|
|
}
|
|
}
|
|
|
|
call_data_dissector(next_tvb, pinfo, tree);
|
|
|
|
if (have_tap_listener(exported_pdu_tap)) {
|
|
exp_pdu_data = export_pdu_create_common_tags(pinfo, "data", EXP_PDU_TAG_PROTO_NAME);
|
|
exp_pdu_data->tvb_captured_length = tvb_captured_length(next_tvb);
|
|
exp_pdu_data->tvb_reported_length = tvb_reported_length(next_tvb);
|
|
exp_pdu_data->pdu_tvb = next_tvb;
|
|
|
|
tap_queue_packet(exported_pdu_tap, pinfo, exp_pdu_data);
|
|
}
|
|
}
|
|
|
|
int
|
|
udp_dissect_pdus(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree,
|
|
guint fixed_len, gboolean (*heuristic_check)(packet_info *, tvbuff_t *, int, void*),
|
|
guint (*get_pdu_len)(packet_info *, tvbuff_t *, int, void*),
|
|
dissector_t dissect_pdu, void* dissector_data)
|
|
{
|
|
volatile int offset = 0;
|
|
int offset_before;
|
|
guint captured_length_remaining;
|
|
volatile guint plen;
|
|
guint length;
|
|
tvbuff_t *next_tvb;
|
|
proto_item *item=NULL;
|
|
const char *saved_proto;
|
|
guint8 curr_layer_num;
|
|
wmem_list_frame_t *frame;
|
|
|
|
while (tvb_reported_length_remaining(tvb, offset) > 0) {
|
|
/*
|
|
* We use "tvb_ensure_captured_length_remaining()" to make
|
|
* sure there actually *is* data remaining. The protocol
|
|
* we're handling could conceivably consists of a sequence of
|
|
* fixed-length PDUs, and therefore the "get_pdu_len" routine
|
|
* might not actually fetch anything from the tvbuff, and thus
|
|
* might not cause an exception to be thrown if we've run past
|
|
* the end of the tvbuff.
|
|
*
|
|
* This means we're guaranteed that "captured_length_remaining" is positive.
|
|
*/
|
|
captured_length_remaining = tvb_ensure_captured_length_remaining(tvb, offset);
|
|
|
|
/*
|
|
* If there is a heuristic function, check it
|
|
*/
|
|
if ((heuristic_check != NULL) &&
|
|
((*heuristic_check)(pinfo, tvb, offset, dissector_data) == FALSE)) {
|
|
return offset;
|
|
}
|
|
|
|
/*
|
|
* Get the length of the PDU.
|
|
*/
|
|
plen = (*get_pdu_len)(pinfo, tvb, offset, dissector_data);
|
|
if (plen == 0) {
|
|
/*
|
|
* Either protocol has variable length (which isn't supposed by UDP)
|
|
* or packet doesn't belong to protocol
|
|
*/
|
|
return offset;
|
|
}
|
|
|
|
if (plen < fixed_len) {
|
|
/*
|
|
* Either:
|
|
*
|
|
* 1) the length value extracted from the fixed-length portion
|
|
* doesn't include the fixed-length portion's length, and
|
|
* was so large that, when the fixed-length portion's
|
|
* length was added to it, the total length overflowed;
|
|
*
|
|
* 2) the length value extracted from the fixed-length portion
|
|
* includes the fixed-length portion's length, and the value
|
|
* was less than the fixed-length portion's length, i.e. it
|
|
* was bogus.
|
|
*
|
|
* Report this as a bounds error.
|
|
*/
|
|
show_reported_bounds_error(tvb, pinfo, tree);
|
|
return offset;
|
|
}
|
|
|
|
curr_layer_num = pinfo->curr_layer_num-1;
|
|
frame = wmem_list_frame_prev(wmem_list_tail(pinfo->layers));
|
|
while (frame && (hfi_udp->id != (gint) GPOINTER_TO_UINT(wmem_list_frame_data(frame)))) {
|
|
frame = wmem_list_frame_prev(frame);
|
|
curr_layer_num--;
|
|
}
|
|
|
|
/*
|
|
* Display the PDU length as a field
|
|
*/
|
|
item=proto_tree_add_uint((proto_tree *)p_get_proto_data(pinfo->pool, pinfo, hfi_udp->id, curr_layer_num),
|
|
&hfi_udp_pdu_size,
|
|
tvb, offset, plen, plen);
|
|
PROTO_ITEM_SET_GENERATED(item);
|
|
|
|
/*
|
|
* Construct a tvbuff containing the amount of the payload we have
|
|
* available. Make its reported length the amount of data in the PDU.
|
|
*/
|
|
length = captured_length_remaining;
|
|
if (length > plen)
|
|
length = plen;
|
|
next_tvb = tvb_new_subset(tvb, offset, length, plen);
|
|
|
|
/*
|
|
* Dissect the PDU.
|
|
*
|
|
* If it gets an error that means there's no point in
|
|
* dissecting any more PDUs, rethrow the exception in
|
|
* question.
|
|
*
|
|
* If it gets any other error, report it and continue, as that
|
|
* means that PDU got an error, but that doesn't mean we should
|
|
* stop dissecting PDUs within this frame or chunk of reassembled
|
|
* data.
|
|
*/
|
|
saved_proto = pinfo->current_proto;
|
|
TRY {
|
|
(*dissect_pdu)(next_tvb, pinfo, tree, dissector_data);
|
|
}
|
|
CATCH_NONFATAL_ERRORS {
|
|
/* Restore the private_data structure in case one of the
|
|
* called dissectors modified it (and, due to the exception,
|
|
* was unable to restore it).
|
|
*/
|
|
show_exception(tvb, pinfo, tree, EXCEPT_CODE, GET_MESSAGE);
|
|
|
|
/*
|
|
* Restore the saved protocol as well; we do this after
|
|
* show_exception(), so that the "Malformed packet" indication
|
|
* shows the protocol for which dissection failed.
|
|
*/
|
|
pinfo->current_proto = saved_proto;
|
|
}
|
|
ENDTRY;
|
|
|
|
/*
|
|
* Step to the next PDU.
|
|
* Make sure we don't overflow.
|
|
*/
|
|
offset_before = offset;
|
|
offset += plen;
|
|
if (offset <= offset_before)
|
|
break;
|
|
}
|
|
|
|
return offset;
|
|
}
|
|
|
|
static gboolean
|
|
capture_udp(const guchar *pd _U_, int offset _U_, int len _U_, capture_packet_info_t *cpinfo, const union wtap_pseudo_header *pseudo_header _U_)
|
|
{
|
|
guint16 src_port, dst_port, low_port, high_port;
|
|
|
|
if (!BYTES_ARE_IN_FRAME(offset, len, 4))
|
|
return FALSE;
|
|
|
|
capture_dissector_increment_count(cpinfo, hfi_udp->id);
|
|
|
|
src_port = pntoh16(&pd[offset]);
|
|
dst_port = pntoh16(&pd[offset+2]);
|
|
|
|
if (src_port > dst_port) {
|
|
low_port = dst_port;
|
|
high_port = src_port;
|
|
} else {
|
|
low_port = src_port;
|
|
high_port = dst_port;
|
|
}
|
|
|
|
if (low_port != 0 &&
|
|
try_capture_dissector("udp.port", low_port, pd, offset+20, len, cpinfo, pseudo_header))
|
|
return TRUE;
|
|
|
|
if (high_port != 0 &&
|
|
try_capture_dissector("udp.port", high_port, pd, offset+20, len, cpinfo, pseudo_header))
|
|
return TRUE;
|
|
|
|
/* We've at least identified one type of packet, so this shouldn't be "other" */
|
|
return TRUE;
|
|
}
|
|
|
|
static void
|
|
dissect(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, guint32 ip_proto)
|
|
{
|
|
proto_tree *udp_tree = NULL;
|
|
proto_item *ti, *item, *hidden_item, *calc_item;
|
|
proto_item *src_port_item, *dst_port_item, *len_cov_item;
|
|
guint len;
|
|
guint reported_len;
|
|
vec_t cksum_vec[4];
|
|
guint32 phdr[2];
|
|
guint16 computed_cksum;
|
|
int offset = 0;
|
|
e_udphdr *udph;
|
|
proto_tree *checksum_tree;
|
|
conversation_t *conv = NULL;
|
|
struct udp_analysis *udpd = NULL;
|
|
proto_tree *process_tree;
|
|
gboolean udp_jumbogram = FALSE;
|
|
|
|
udph = wmem_new0(wmem_packet_scope(), e_udphdr);
|
|
udph->uh_sport = tvb_get_ntohs(tvb, offset);
|
|
udph->uh_dport = tvb_get_ntohs(tvb, offset + 2);
|
|
copy_address_shallow(&udph->ip_src, &pinfo->src);
|
|
copy_address_shallow(&udph->ip_dst, &pinfo->dst);
|
|
|
|
col_set_str(pinfo->cinfo, COL_PROTOCOL, (ip_proto == IP_PROTO_UDP) ? "UDP" : "UDP-Lite");
|
|
col_clear(pinfo->cinfo, COL_INFO);
|
|
col_append_ports(pinfo->cinfo, COL_INFO, PT_UDP, udph->uh_sport, udph->uh_dport);
|
|
|
|
reported_len = tvb_reported_length(tvb);
|
|
len = tvb_captured_length(tvb);
|
|
|
|
ti = proto_tree_add_item(tree, (ip_proto == IP_PROTO_UDP) ? hfi_udp : hfi_udplite, tvb, offset, 8, ENC_NA);
|
|
if (udp_summary_in_tree) {
|
|
proto_item_append_text(ti, ", Src Port: %s, Dst Port: %s",
|
|
port_with_resolution_to_str(wmem_packet_scope(), PT_UDP, udph->uh_sport),
|
|
port_with_resolution_to_str(wmem_packet_scope(), PT_UDP, udph->uh_dport));
|
|
}
|
|
udp_tree = proto_item_add_subtree(ti, ett_udp);
|
|
p_add_proto_data(pinfo->pool, pinfo, hfi_udp->id, pinfo->curr_layer_num, udp_tree);
|
|
|
|
src_port_item = proto_tree_add_item(udp_tree, &hfi_udp_srcport, tvb, offset, 2, ENC_BIG_ENDIAN);
|
|
dst_port_item = proto_tree_add_item(udp_tree, &hfi_udp_dstport, tvb, offset + 2, 2, ENC_BIG_ENDIAN);
|
|
|
|
hidden_item = proto_tree_add_item(udp_tree, &hfi_udp_port, tvb, offset, 2, ENC_BIG_ENDIAN);
|
|
PROTO_ITEM_SET_HIDDEN(hidden_item);
|
|
hidden_item = proto_tree_add_item(udp_tree, &hfi_udp_port, tvb, offset + 2, 2, ENC_BIG_ENDIAN);
|
|
PROTO_ITEM_SET_HIDDEN(hidden_item);
|
|
|
|
/* The beginning port number, 32768 + 666 (33434), is from LBL's traceroute.c source code and this code
|
|
* further assumes that 3 attempts are made per hop */
|
|
if ((udph->uh_sport > (32768 + 666)) && (udph->uh_sport <= (32768 + 666 + 30))) {
|
|
expert_add_info_format(pinfo, src_port_item, &ei_udp_possible_traceroute, "Possible traceroute: hop #%u, attempt #%u",
|
|
((udph->uh_sport - 32768 - 666 - 1) / 3) + 1,
|
|
((udph->uh_sport - 32768 - 666 - 1) % 3) + 1);
|
|
}
|
|
if ((udph->uh_dport > (32768 + 666)) && (udph->uh_dport <= (32768 + 666 + 30))) {
|
|
expert_add_info_format(pinfo, dst_port_item, &ei_udp_possible_traceroute, "Possible traceroute: hop #%u, attempt #%u",
|
|
((udph->uh_dport - 32768 - 666 - 1) / 3) + 1,
|
|
((udph->uh_dport - 32768 - 666 - 1) % 3) + 1);
|
|
}
|
|
|
|
udph->uh_ulen = udph->uh_sum_cov = tvb_get_ntohs(tvb, offset + 4);
|
|
if (ip_proto == IP_PROTO_UDP) {
|
|
len_cov_item = proto_tree_add_item(udp_tree, &hfi_udp_length, tvb, offset + 4, 2, ENC_BIG_ENDIAN);
|
|
if (udph->uh_ulen == 0 && pinfo->src.type == AT_IPv6) {
|
|
/* RFC 2675 (section 4) - UDP Jumbograms */
|
|
udph->uh_ulen = udph->uh_sum_cov = reported_len;
|
|
udp_jumbogram = TRUE;
|
|
}
|
|
if (udph->uh_ulen < 8) {
|
|
/* Bogus length - it includes the header, so it must be >= 8. */
|
|
proto_item_append_text(len_cov_item, " (bogus, must be >= 8)");
|
|
expert_add_info_format(pinfo, len_cov_item, &ei_udp_length_bad, "Bad length value %u < 8", udph->uh_ulen);
|
|
col_append_fstr(pinfo->cinfo, COL_INFO, " [BAD UDP LENGTH %u < 8]", udph->uh_ulen);
|
|
return;
|
|
}
|
|
if ((udph->uh_ulen > reported_len) && (!pinfo->fragmented) && (!pinfo->flags.in_error_pkt)) {
|
|
/* Bogus length - it goes past the end of the IP payload */
|
|
proto_item_append_text(len_cov_item, " (bogus, payload length %u)", reported_len);
|
|
expert_add_info_format(pinfo, len_cov_item, &ei_udp_length_bad, "Bad length value %u > IP payload length", udph->uh_ulen);
|
|
col_append_fstr(pinfo->cinfo, COL_INFO, " [BAD UDP LENGTH %u > IP PAYLOAD LENGTH]", udph->uh_ulen);
|
|
/*return;*/
|
|
}
|
|
if (udp_jumbogram && (udph->uh_ulen < 65536)) {
|
|
expert_add_info(pinfo, len_cov_item, &ei_udp_length_bad_zero);
|
|
}
|
|
} else {
|
|
len_cov_item = proto_tree_add_item(udp_tree, &hfi_udplite_checksum_coverage, tvb, offset + 4, 2, ENC_BIG_ENDIAN);
|
|
udph->uh_ulen = reported_len;
|
|
if (udph->uh_sum_cov == 0) {
|
|
udph->uh_sum_cov = reported_len;
|
|
}
|
|
item = proto_tree_add_uint(udp_tree, &hfi_udp_length, tvb, offset + 4, 0, udph->uh_ulen);
|
|
PROTO_ITEM_SET_GENERATED(item);
|
|
if ((udph->uh_sum_cov < 8) || (udph->uh_sum_cov > udph->uh_ulen)) {
|
|
/* Bogus coverage - it includes the header, so it must be >= 8, and no larger then the IP payload size. */
|
|
proto_item_append_text(len_cov_item, " (bogus, must be >= 8 and <= %u)", udph->uh_ulen);
|
|
expert_add_info_format(pinfo, len_cov_item, &ei_udplite_checksum_coverage_bad, "Bad checksum coverage length value %u < 8 or > %u",
|
|
udph->uh_sum_cov, udph->uh_ulen);
|
|
col_append_fstr(pinfo->cinfo, COL_INFO, " [BAD LIGHTWEIGHT UDP CHECKSUM COVERAGE LENGTH %u < 8 or > %u]",
|
|
udph->uh_sum_cov, udph->uh_ulen);
|
|
if (!udplite_ignore_checksum_coverage) {
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
|
|
col_append_str_uint(pinfo->cinfo, COL_INFO, "Len", udph->uh_ulen - 8, " "); /* Payload length */
|
|
if (udp_jumbogram)
|
|
col_append_str(pinfo->cinfo, COL_INFO, " [Jumbogram]");
|
|
|
|
udph->uh_sum = tvb_get_ntohs(tvb, offset + 6);
|
|
if (udph->uh_sum == 0) {
|
|
/* No checksum supplied in the packet. */
|
|
if (((ip_proto == IP_PROTO_UDP) && (pinfo->src.type == AT_IPv4)) || pinfo->flags.in_error_pkt) {
|
|
proto_tree_add_checksum(udp_tree, tvb, offset + 6, hfi_udp_checksum.id, hfi_udp_checksum_status.id, &ei_udp_checksum_bad,
|
|
pinfo, 0, ENC_BIG_ENDIAN, PROTO_CHECKSUM_NO_FLAGS);
|
|
} else {
|
|
item = proto_tree_add_uint_format_value(udp_tree, hfi_udp_checksum.id, tvb, offset + 6, 2, 0, "0 (Illegal)");
|
|
checksum_tree = proto_item_add_subtree(item, ett_udp_checksum);
|
|
|
|
expert_add_info(pinfo, item, &ei_udp_checksum_zero);
|
|
col_append_str(pinfo->cinfo, COL_INFO, " [ILLEGAL CHECKSUM (0)]");
|
|
|
|
/* XXX - What should this special status be? */
|
|
item = proto_tree_add_uint(checksum_tree, &hfi_udp_checksum_status, tvb,
|
|
offset + 6, 0, 4);
|
|
PROTO_ITEM_SET_GENERATED(item);
|
|
}
|
|
} else if (!pinfo->fragmented && (len >= reported_len) &&
|
|
(len >= udph->uh_sum_cov) && (reported_len >= udph->uh_sum_cov) &&
|
|
(udph->uh_sum_cov >= 8)) {
|
|
/* The packet isn't part of a fragmented datagram and isn't
|
|
truncated, so we can checksum it.
|
|
XXX - make a bigger scatter-gather list once we do fragment
|
|
reassembly? */
|
|
|
|
if (((ip_proto == IP_PROTO_UDP) && udp_check_checksum) ||
|
|
((ip_proto == IP_PROTO_UDPLITE) && udplite_check_checksum)) {
|
|
/* Set up the fields of the pseudo-header. */
|
|
SET_CKSUM_VEC_PTR(cksum_vec[0], (const guint8 *)pinfo->src.data, pinfo->src.len);
|
|
SET_CKSUM_VEC_PTR(cksum_vec[1], (const guint8 *)pinfo->dst.data, pinfo->dst.len);
|
|
switch (pinfo->src.type) {
|
|
|
|
case AT_IPv4:
|
|
if (ip_proto == IP_PROTO_UDP)
|
|
phdr[0] = g_htonl((ip_proto<<16) | udph->uh_ulen);
|
|
else
|
|
phdr[0] = g_htonl((ip_proto<<16) | reported_len);
|
|
SET_CKSUM_VEC_PTR(cksum_vec[2], (const guint8 *)&phdr, 4);
|
|
break;
|
|
|
|
case AT_IPv6:
|
|
if (ip_proto == IP_PROTO_UDP)
|
|
phdr[0] = g_htonl(udph->uh_ulen);
|
|
else
|
|
phdr[0] = g_htonl(reported_len);
|
|
phdr[1] = g_htonl(ip_proto);
|
|
SET_CKSUM_VEC_PTR(cksum_vec[2], (const guint8 *)&phdr, 8);
|
|
break;
|
|
|
|
default:
|
|
/* UDP runs only atop IPv4 and IPv6.... */
|
|
DISSECTOR_ASSERT_NOT_REACHED();
|
|
break;
|
|
}
|
|
SET_CKSUM_VEC_TVB(cksum_vec[3], tvb, offset, udph->uh_sum_cov);
|
|
computed_cksum = in_cksum(&cksum_vec[0], 4);
|
|
|
|
item = proto_tree_add_checksum(udp_tree, tvb, offset+6, hfi_udp_checksum.id, hfi_udp_checksum_status.id, &ei_udp_checksum_bad,
|
|
pinfo, computed_cksum, ENC_BIG_ENDIAN, PROTO_CHECKSUM_VERIFY|PROTO_CHECKSUM_IN_CKSUM);
|
|
checksum_tree = proto_item_add_subtree(item, ett_udp_checksum);
|
|
|
|
if (computed_cksum != 0) {
|
|
proto_item_append_text(item, "(maybe caused by \"UDP checksum offload\"?)");
|
|
col_append_str(pinfo->cinfo, COL_INFO, " [UDP CHECKSUM INCORRECT]");
|
|
calc_item = proto_tree_add_uint(checksum_tree, &hfi_udp_checksum_calculated,
|
|
tvb, offset + 6, 2, in_cksum_shouldbe(udph->uh_sum, computed_cksum));
|
|
} else {
|
|
calc_item = proto_tree_add_uint(checksum_tree, &hfi_udp_checksum_calculated,
|
|
tvb, offset + 6, 2, udph->uh_sum);
|
|
}
|
|
PROTO_ITEM_SET_GENERATED(calc_item);
|
|
|
|
} else {
|
|
proto_tree_add_checksum(udp_tree, tvb, offset + 6, hfi_udp_checksum.id, hfi_udp_checksum_status.id, &ei_udp_checksum_bad, pinfo, 0, ENC_BIG_ENDIAN, PROTO_CHECKSUM_NO_FLAGS);
|
|
}
|
|
} else {
|
|
proto_tree_add_checksum(udp_tree, tvb, offset + 6, hfi_udp_checksum.id, hfi_udp_checksum_status.id, &ei_udp_checksum_bad, pinfo, 0, ENC_BIG_ENDIAN, PROTO_CHECKSUM_NO_FLAGS);
|
|
}
|
|
|
|
/* Skip over header */
|
|
offset += 8;
|
|
|
|
pinfo->ptype = PT_UDP;
|
|
pinfo->srcport = udph->uh_sport;
|
|
pinfo->destport = udph->uh_dport;
|
|
|
|
/* find(or create if needed) the conversation for this udp session */
|
|
conv = find_or_create_conversation(pinfo);
|
|
udpd = get_udp_conversation_data(conv, pinfo);
|
|
if (udpd) {
|
|
item = proto_tree_add_uint(udp_tree, &hfi_udp_stream, tvb, offset, 0, udpd->stream);
|
|
PROTO_ITEM_SET_GENERATED(item);
|
|
|
|
/* Copy the stream index into the header as well to make it available
|
|
* to tap listeners.
|
|
*/
|
|
udph->uh_stream = udpd->stream;
|
|
}
|
|
|
|
tap_queue_packet(udp_tap, pinfo, udph);
|
|
|
|
if (udpd && ((udpd->fwd && udpd->fwd->command) || (udpd->rev && udpd->rev->command))) {
|
|
process_tree = proto_tree_add_subtree(udp_tree, tvb, offset, 0, ett_udp_process_info, &ti, "Process Information");
|
|
PROTO_ITEM_SET_GENERATED(ti);
|
|
if (udpd->fwd && udpd->fwd->command) {
|
|
proto_tree_add_uint_format_value(process_tree, hfi_udp_proc_dst_uid.id, tvb, 0, 0,
|
|
udpd->fwd->process_uid, "%u", udpd->fwd->process_uid);
|
|
proto_tree_add_uint_format_value(process_tree, hfi_udp_proc_dst_pid.id, tvb, 0, 0,
|
|
udpd->fwd->process_pid, "%u", udpd->fwd->process_pid);
|
|
proto_tree_add_string_format_value(process_tree, hfi_udp_proc_dst_uname.id, tvb, 0, 0,
|
|
udpd->fwd->username, "%s", udpd->fwd->username);
|
|
proto_tree_add_string_format_value(process_tree, hfi_udp_proc_dst_cmd.id, tvb, 0, 0,
|
|
udpd->fwd->command, "%s", udpd->fwd->command);
|
|
}
|
|
if (udpd->rev->command) {
|
|
proto_tree_add_uint_format_value(process_tree, hfi_udp_proc_src_uid.id, tvb, 0, 0,
|
|
udpd->rev->process_uid, "%u", udpd->rev->process_uid);
|
|
proto_tree_add_uint_format_value(process_tree, hfi_udp_proc_src_pid.id, tvb, 0, 0,
|
|
udpd->rev->process_pid, "%u", udpd->rev->process_pid);
|
|
proto_tree_add_string_format_value(process_tree, hfi_udp_proc_src_uname.id, tvb, 0, 0,
|
|
udpd->rev->username, "%s", udpd->rev->username);
|
|
proto_tree_add_string_format_value(process_tree, hfi_udp_proc_src_cmd.id, tvb, 0, 0,
|
|
udpd->rev->command, "%s", udpd->rev->command);
|
|
}
|
|
}
|
|
|
|
if (udph->uh_ulen == 8) {
|
|
/* Empty UDP payload, nothing left to do. */
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Call sub-dissectors.
|
|
*
|
|
* XXX - should we do this if this is included in an error packet?
|
|
* It might be nice to see the details of the packet that caused the
|
|
* ICMP error, but it might not be nice to have the dissector update
|
|
* state based on it.
|
|
* Also, we probably don't want to run UDP taps on those packets.
|
|
*
|
|
* We definitely don't want to do it for an error packet if there's
|
|
* nothing left in the packet.
|
|
*/
|
|
if (!pinfo->flags.in_error_pkt || (tvb_captured_length_remaining(tvb, offset) > 0))
|
|
decode_udp_ports(tvb, offset, pinfo, tree, udph->uh_sport, udph->uh_dport, udph->uh_ulen);
|
|
}
|
|
|
|
static int
|
|
dissect_udp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
|
|
{
|
|
dissect(tvb, pinfo, tree, IP_PROTO_UDP);
|
|
return tvb_captured_length(tvb);
|
|
}
|
|
|
|
static int
|
|
dissect_udplite(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
|
|
{
|
|
dissect(tvb, pinfo, tree, IP_PROTO_UDPLITE);
|
|
return tvb_captured_length(tvb);
|
|
}
|
|
|
|
static void
|
|
udp_init(void)
|
|
{
|
|
udp_stream_count = 0;
|
|
}
|
|
|
|
void
|
|
proto_register_udp(void)
|
|
{
|
|
module_t *udp_module;
|
|
module_t *udplite_module;
|
|
expert_module_t* expert_udp;
|
|
|
|
#ifndef HAVE_HFI_SECTION_INIT
|
|
static header_field_info *hfi[] = {
|
|
&hfi_udp_srcport,
|
|
&hfi_udp_dstport,
|
|
&hfi_udp_port,
|
|
&hfi_udp_stream,
|
|
&hfi_udp_length,
|
|
&hfi_udp_checksum,
|
|
&hfi_udp_checksum_calculated,
|
|
&hfi_udp_checksum_status,
|
|
&hfi_udp_proc_src_uid,
|
|
&hfi_udp_proc_src_pid,
|
|
&hfi_udp_proc_src_uname,
|
|
&hfi_udp_proc_src_cmd,
|
|
&hfi_udp_proc_dst_uid,
|
|
&hfi_udp_proc_dst_pid,
|
|
&hfi_udp_proc_dst_uname,
|
|
&hfi_udp_proc_dst_cmd,
|
|
&hfi_udp_pdu_size,
|
|
};
|
|
|
|
static header_field_info *hfi_lite[] = {
|
|
&hfi_udplite_checksum_coverage,
|
|
};
|
|
#endif
|
|
|
|
static gint *ett[] = {
|
|
&ett_udp,
|
|
&ett_udp_checksum,
|
|
&ett_udp_process_info
|
|
};
|
|
|
|
static ei_register_info ei[] = {
|
|
{ &ei_udp_possible_traceroute, { "udp.possible_traceroute", PI_SEQUENCE, PI_CHAT, "Possible traceroute", EXPFILL }},
|
|
{ &ei_udp_length_bad, { "udp.length.bad", PI_MALFORMED, PI_ERROR, "Bad length value", EXPFILL }},
|
|
{ &ei_udplite_checksum_coverage_bad, { "udplite.checksum_coverage.bad", PI_MALFORMED, PI_ERROR, "Bad checksum coverage length value", EXPFILL }},
|
|
{ &ei_udp_checksum_zero, { "udp.checksum.zero", PI_CHECKSUM, PI_ERROR, "Illegal Checksum value (0)", EXPFILL }},
|
|
{ &ei_udp_checksum_bad, { "udp.checksum.bad", PI_CHECKSUM, PI_ERROR, "Bad checksum", EXPFILL }},
|
|
{ &ei_udp_length_bad_zero, { "udp.length.bad_zero", PI_PROTOCOL, PI_WARN, "Length is zero but payload < 65536", EXPFILL }},
|
|
};
|
|
|
|
static build_valid_func udp_da_src_values[1] = {udp_src_value};
|
|
static build_valid_func udp_da_dst_values[1] = {udp_dst_value};
|
|
static build_valid_func udp_da_both_values[2] = {udp_src_value, udp_dst_value};
|
|
static decode_as_value_t udp_da_values[3] = {{udp_src_prompt, 1, udp_da_src_values}, {udp_dst_prompt, 1, udp_da_dst_values}, {udp_both_prompt, 2, udp_da_both_values}};
|
|
static decode_as_t udp_da = {"udp", "Transport", "udp.port", 3, 2, udp_da_values, "UDP", "port(s) as",
|
|
decode_as_default_populate_list, decode_as_default_reset, decode_as_default_change, NULL};
|
|
|
|
int proto_udp, proto_udplite;
|
|
|
|
proto_udp = proto_register_protocol("User Datagram Protocol",
|
|
"UDP", "udp");
|
|
hfi_udp = proto_registrar_get_nth(proto_udp);
|
|
udp_handle = register_dissector("udp", dissect_udp, proto_udp);
|
|
expert_udp = expert_register_protocol(proto_udp);
|
|
proto_register_fields(proto_udp, hfi, array_length(hfi));
|
|
|
|
proto_udplite = proto_register_protocol("Lightweight User Datagram Protocol",
|
|
"UDP-Lite", "udplite");
|
|
udplite_handle = create_dissector_handle(dissect_udplite, proto_udplite);
|
|
hfi_udplite = proto_registrar_get_nth(proto_udplite);
|
|
proto_register_fields(proto_udplite, hfi_lite, array_length(hfi_lite));
|
|
|
|
proto_register_subtree_array(ett, array_length(ett));
|
|
expert_register_field_array(expert_udp, ei, array_length(ei));
|
|
|
|
/* subdissector code */
|
|
udp_dissector_table = register_dissector_table("udp.port",
|
|
"UDP port", proto_udp, FT_UINT16, BASE_DEC);
|
|
heur_subdissector_list = register_heur_dissector_list("udp", proto_udp);
|
|
|
|
register_capture_dissector_table("udp.port", "UDP");
|
|
|
|
/* Register configuration preferences */
|
|
udp_module = prefs_register_protocol(proto_udp, NULL);
|
|
prefs_register_bool_preference(udp_module, "summary_in_tree",
|
|
"Show UDP summary in protocol tree",
|
|
"Whether the UDP summary line should be shown in the protocol tree",
|
|
&udp_summary_in_tree);
|
|
prefs_register_bool_preference(udp_module, "try_heuristic_first",
|
|
"Try heuristic sub-dissectors first",
|
|
"Try to decode a packet using an heuristic sub-dissector"
|
|
" before using a sub-dissector registered to a specific port",
|
|
&try_heuristic_first);
|
|
prefs_register_bool_preference(udp_module, "check_checksum",
|
|
"Validate the UDP checksum if possible",
|
|
"Whether to validate the UDP checksum",
|
|
&udp_check_checksum);
|
|
prefs_register_bool_preference(udp_module, "process_info",
|
|
"Collect process flow information",
|
|
"Collect process flow information from IPFIX",
|
|
&udp_process_info);
|
|
|
|
udplite_module = prefs_register_protocol(proto_udplite, NULL);
|
|
prefs_register_bool_preference(udplite_module, "ignore_checksum_coverage",
|
|
"Ignore UDP-Lite checksum coverage",
|
|
"Ignore an invalid checksum coverage field and continue dissection",
|
|
&udplite_ignore_checksum_coverage);
|
|
prefs_register_bool_preference(udplite_module, "check_checksum",
|
|
"Validate the UDP-Lite checksum if possible",
|
|
"Whether to validate the UDP-Lite checksum",
|
|
&udplite_check_checksum);
|
|
|
|
register_decode_as(&udp_da);
|
|
register_conversation_table(proto_udp, FALSE, udpip_conversation_packet, udpip_hostlist_packet);
|
|
register_conversation_filter("udp", "UDP", udp_filter_valid, udp_build_filter);
|
|
register_follow_stream(proto_udp, "udp_follow", udp_follow_conv_filter, udp_follow_index_filter, udp_follow_address_filter,
|
|
udp_port_to_display, follow_tvb_tap_listener);
|
|
|
|
register_init_routine(udp_init);
|
|
|
|
}
|
|
|
|
void
|
|
proto_reg_handoff_udp(void)
|
|
{
|
|
capture_dissector_handle_t udp_cap_handle;
|
|
|
|
dissector_add_uint("ip.proto", IP_PROTO_UDP, udp_handle);
|
|
dissector_add_uint("ip.proto", IP_PROTO_UDPLITE, udplite_handle);
|
|
|
|
udp_cap_handle = create_capture_dissector_handle(capture_udp, hfi_udp->id);
|
|
capture_dissector_add_uint("ip.proto", IP_PROTO_UDP, udp_cap_handle);
|
|
udp_cap_handle = create_capture_dissector_handle(capture_udp, hfi_udplite->id);
|
|
capture_dissector_add_uint("ip.proto", IP_PROTO_UDPLITE, udp_cap_handle);
|
|
|
|
udp_tap = register_tap("udp");
|
|
udp_follow_tap = register_tap("udp_follow");
|
|
exported_pdu_tap = find_tap_id(EXPORT_PDU_TAP_NAME_LAYER_4);
|
|
}
|
|
|
|
/*
|
|
* Editor modelines - http://www.wireshark.org/tools/modelines.html
|
|
*
|
|
* Local variables:
|
|
* c-basic-offset: 2
|
|
* tab-width: 8
|
|
* indent-tabs-mode: nil
|
|
* End:
|
|
*
|
|
* vi: set shiftwidth=2 tabstop=8 expandtab:
|
|
* :indentSize=2:tabSize=8:noTabs=true:
|
|
*/
|