forked from osmocom/wireshark
![Guy Harris](/assets/img/avatar_default.png)
"proto_tree_add_item_hidden()", to add the "checksum bad" flags to packets; the value should be "TRUE", not the numerical value of the checksum field. svn path=/trunk/; revision=3202
751 lines
21 KiB
C
751 lines
21 KiB
C
/* packet-tcp.c
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* Routines for TCP packet disassembly
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*
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* $Id: packet-tcp.c,v 1.101 2001/03/28 21:33:31 guy Exp $
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*
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* Ethereal - Network traffic analyzer
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* By Gerald Combs <gerald@zing.org>
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* Copyright 1998 Gerald Combs
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*
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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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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*/
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#ifdef HAVE_CONFIG_H
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# include "config.h"
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#endif
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#ifdef HAVE_SYS_TYPES_H
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# include <sys/types.h>
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#endif
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#ifdef HAVE_NETINET_IN_H
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# include <netinet/in.h>
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#endif
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#include <stdio.h>
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#include <string.h>
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#include <glib.h>
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#include "in_cksum.h"
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#ifdef NEED_SNPRINTF_H
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# include "snprintf.h"
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#endif
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#include "globals.h"
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#include "resolv.h"
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#include "follow.h"
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#include "prefs.h"
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#include "packet-tcp.h"
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#include "packet-ip.h"
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#include "conversation.h"
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#include "strutil.h"
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/* Place TCP summary in proto tree */
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static gboolean tcp_summary_in_tree = TRUE;
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extern FILE* data_out_file;
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guint16 tcp_urgent_pointer;
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static int proto_tcp = -1;
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static int hf_tcp_srcport = -1;
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static int hf_tcp_dstport = -1;
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static int hf_tcp_port = -1;
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static int hf_tcp_seq = -1;
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static int hf_tcp_nxtseq = -1;
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static int hf_tcp_ack = -1;
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static int hf_tcp_hdr_len = -1;
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static int hf_tcp_flags = -1;
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static int hf_tcp_flags_cwr = -1;
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static int hf_tcp_flags_ecn = -1;
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static int hf_tcp_flags_urg = -1;
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static int hf_tcp_flags_ack = -1;
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static int hf_tcp_flags_push = -1;
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static int hf_tcp_flags_reset = -1;
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static int hf_tcp_flags_syn = -1;
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static int hf_tcp_flags_fin = -1;
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static int hf_tcp_window_size = -1;
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static int hf_tcp_checksum = -1;
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static int hf_tcp_checksum_bad = -1;
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static int hf_tcp_urgent_pointer = -1;
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static gint ett_tcp = -1;
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static gint ett_tcp_flags = -1;
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static gint ett_tcp_options = -1;
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static gint ett_tcp_option_sack = -1;
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static dissector_table_t subdissector_table;
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static heur_dissector_list_t heur_subdissector_list;
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static conv_dissector_list_t conv_subdissector_list;
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/* TCP Ports */
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#define TCP_PORT_SMTP 25
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/* TCP structs and definitions */
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typedef struct _e_tcphdr {
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guint16 th_sport;
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guint16 th_dport;
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guint32 th_seq;
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guint32 th_ack;
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guint8 th_off_x2; /* combines th_off and th_x2 */
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guint8 th_flags;
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#define TH_FIN 0x01
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#define TH_SYN 0x02
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#define TH_RST 0x04
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#define TH_PUSH 0x08
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#define TH_ACK 0x10
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#define TH_URG 0x20
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#define TH_ECN 0x40
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#define TH_CWR 0x80
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guint16 th_win;
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guint16 th_sum;
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guint16 th_urp;
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} e_tcphdr;
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/*
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* TCP option
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*/
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#define TCPOPT_NOP 1 /* Padding */
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#define TCPOPT_EOL 0 /* End of options */
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#define TCPOPT_MSS 2 /* Segment size negotiating */
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#define TCPOPT_WINDOW 3 /* Window scaling */
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#define TCPOPT_SACK_PERM 4 /* SACK Permitted */
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#define TCPOPT_SACK 5 /* SACK Block */
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#define TCPOPT_ECHO 6
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#define TCPOPT_ECHOREPLY 7
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#define TCPOPT_TIMESTAMP 8 /* Better RTT estimations/PAWS */
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#define TCPOPT_CC 11
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#define TCPOPT_CCNEW 12
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#define TCPOPT_CCECHO 13
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#define TCPOPT_MD5 19 /* RFC2385 */
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/*
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* TCP option lengths
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*/
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#define TCPOLEN_MSS 4
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#define TCPOLEN_WINDOW 3
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#define TCPOLEN_SACK_PERM 2
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#define TCPOLEN_SACK_MIN 2
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#define TCPOLEN_ECHO 6
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#define TCPOLEN_ECHOREPLY 6
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#define TCPOLEN_TIMESTAMP 10
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#define TCPOLEN_CC 6
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#define TCPOLEN_CCNEW 6
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#define TCPOLEN_CCECHO 6
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#define TCPOLEN_MD5 18
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static void
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tcp_info_append_uint(frame_data *fd, const char *abbrev, guint32 val)
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{
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if (check_col(fd, COL_INFO))
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col_append_fstr(fd, COL_INFO, " %s=%u", abbrev, val);
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}
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static void
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dissect_tcpopt_maxseg(const ip_tcp_opt *optp, tvbuff_t *tvb,
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int offset, guint optlen, frame_data *fd, proto_tree *opt_tree)
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{
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guint16 mss;
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mss = tvb_get_ntohs(tvb, offset + 2);
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proto_tree_add_text(opt_tree, tvb, offset, optlen,
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"%s: %u bytes", optp->name, mss);
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tcp_info_append_uint(fd, "MSS", mss);
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}
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static void
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dissect_tcpopt_wscale(const ip_tcp_opt *optp, tvbuff_t *tvb,
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int offset, guint optlen, frame_data *fd, proto_tree *opt_tree)
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{
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guint8 ws;
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ws = tvb_get_guint8(tvb, offset + 2);
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proto_tree_add_text(opt_tree, tvb, offset, optlen,
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"%s: %u bytes", optp->name, ws);
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tcp_info_append_uint(fd, "WS", ws);
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}
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static void
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dissect_tcpopt_sack(const ip_tcp_opt *optp, tvbuff_t *tvb,
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int offset, guint optlen, frame_data *fd, proto_tree *opt_tree)
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{
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proto_tree *field_tree = NULL;
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proto_item *tf;
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guint leftedge, rightedge;
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tf = proto_tree_add_text(opt_tree, tvb, offset, optlen, "%s:", optp->name);
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offset += 2; /* skip past type and length */
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optlen -= 2; /* subtract size of type and length */
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while (optlen > 0) {
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if (field_tree == NULL) {
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/* Haven't yet made a subtree out of this option. Do so. */
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field_tree = proto_item_add_subtree(tf, *optp->subtree_index);
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}
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if (optlen < 4) {
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proto_tree_add_text(field_tree, tvb, offset, optlen,
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"(suboption would go past end of option)");
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break;
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}
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leftedge = tvb_get_ntohl(tvb, offset);
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optlen -= 4;
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if (optlen < 4) {
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proto_tree_add_text(field_tree, tvb, offset, optlen,
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"(suboption would go past end of option)");
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break;
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}
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/* XXX - check whether it goes past end of packet */
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rightedge = tvb_get_ntohl(tvb, offset + 4);
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optlen -= 4;
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proto_tree_add_text(field_tree, tvb, offset, 8,
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"left edge = %u, right edge = %u", leftedge, rightedge);
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tcp_info_append_uint(fd, "SLE", leftedge);
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tcp_info_append_uint(fd, "SRE", rightedge);
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offset += 8;
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}
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}
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static void
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dissect_tcpopt_echo(const ip_tcp_opt *optp, tvbuff_t *tvb,
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int offset, guint optlen, frame_data *fd, proto_tree *opt_tree)
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{
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guint32 echo;
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echo = tvb_get_ntohl(tvb, offset + 2);
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proto_tree_add_text(opt_tree, tvb, offset, optlen,
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"%s: %u", optp->name, echo);
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tcp_info_append_uint(fd, "ECHO", echo);
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}
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static void
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dissect_tcpopt_timestamp(const ip_tcp_opt *optp, tvbuff_t *tvb,
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int offset, guint optlen, frame_data *fd, proto_tree *opt_tree)
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{
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guint32 tsv, tser;
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tsv = tvb_get_ntohl(tvb, offset + 2);
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tser = tvb_get_ntohl(tvb, offset + 6);
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proto_tree_add_text(opt_tree, tvb, offset, optlen,
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"%s: tsval %u, tsecr %u", optp->name, tsv, tser);
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tcp_info_append_uint(fd, "TSV", tsv);
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tcp_info_append_uint(fd, "TSER", tser);
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}
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static void
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dissect_tcpopt_cc(const ip_tcp_opt *optp, tvbuff_t *tvb,
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int offset, guint optlen, frame_data *fd, proto_tree *opt_tree)
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{
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guint32 cc;
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cc = tvb_get_ntohl(tvb, offset + 2);
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proto_tree_add_text(opt_tree, tvb, offset, optlen,
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"%s: %u", optp->name, cc);
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tcp_info_append_uint(fd, "CC", cc);
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}
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static const ip_tcp_opt tcpopts[] = {
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{
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TCPOPT_EOL,
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"EOL",
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NULL,
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NO_LENGTH,
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0,
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NULL,
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},
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{
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TCPOPT_NOP,
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"NOP",
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NULL,
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NO_LENGTH,
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0,
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NULL,
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},
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{
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TCPOPT_MSS,
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"Maximum segment size",
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NULL,
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FIXED_LENGTH,
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TCPOLEN_MSS,
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dissect_tcpopt_maxseg
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},
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{
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TCPOPT_WINDOW,
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"Window scale",
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NULL,
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FIXED_LENGTH,
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TCPOLEN_WINDOW,
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dissect_tcpopt_wscale
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},
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{
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TCPOPT_SACK_PERM,
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"SACK permitted",
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NULL,
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FIXED_LENGTH,
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TCPOLEN_SACK_PERM,
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NULL,
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},
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{
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TCPOPT_SACK,
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"SACK",
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&ett_tcp_option_sack,
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VARIABLE_LENGTH,
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TCPOLEN_SACK_MIN,
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dissect_tcpopt_sack
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},
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{
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TCPOPT_ECHO,
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"Echo",
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NULL,
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FIXED_LENGTH,
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TCPOLEN_ECHO,
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dissect_tcpopt_echo
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},
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{
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TCPOPT_ECHOREPLY,
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"Echo reply",
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NULL,
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FIXED_LENGTH,
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TCPOLEN_ECHOREPLY,
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dissect_tcpopt_echo
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},
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{
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TCPOPT_TIMESTAMP,
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"Time stamp",
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NULL,
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FIXED_LENGTH,
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TCPOLEN_TIMESTAMP,
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dissect_tcpopt_timestamp
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},
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{
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TCPOPT_CC,
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"CC",
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NULL,
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FIXED_LENGTH,
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TCPOLEN_CC,
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dissect_tcpopt_cc
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},
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{
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TCPOPT_CCNEW,
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"CC.NEW",
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NULL,
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FIXED_LENGTH,
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TCPOPT_CCNEW,
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dissect_tcpopt_cc
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},
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{
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TCPOPT_CCECHO,
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"CC.ECHO",
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NULL,
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FIXED_LENGTH,
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TCPOLEN_CCECHO,
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dissect_tcpopt_cc
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},
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{
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TCPOPT_MD5,
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"TCP MD5 signature",
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NULL,
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FIXED_LENGTH,
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TCPOLEN_MD5,
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NULL
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}
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};
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#define N_TCP_OPTS (sizeof tcpopts / sizeof tcpopts[0])
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/* TCP flags flag */
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static const true_false_string flags_set_truth = {
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"Set",
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"Not set"
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};
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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 to other protocol dissectors */
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/* can call to it, ie. socks */
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void
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decode_tcp_ports(tvbuff_t *tvb, int offset, packet_info *pinfo,
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proto_tree *tree, int src_port, int dst_port)
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{
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tvbuff_t *next_tvb;
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next_tvb = tvb_new_subset(tvb, offset, -1, -1);
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/* determine if this packet is part of a conversation and call dissector */
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/* for the conversation if available */
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if (try_conversation_dissector(&pinfo->src, &pinfo->dst, PT_TCP,
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src_port, dst_port, next_tvb, pinfo, tree))
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return;
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/* do lookup with the subdissector table */
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if (dissector_try_port(subdissector_table, src_port, next_tvb, pinfo, tree) ||
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dissector_try_port(subdissector_table, dst_port, next_tvb, pinfo, tree))
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return;
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/* do lookup with the heuristic subdissector table */
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if (dissector_try_heuristic(heur_subdissector_list, next_tvb, pinfo, tree))
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return;
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/* Oh, well, we don't know this; dissect it as data. */
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dissect_data(next_tvb, 0, pinfo, tree);
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}
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static void
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dissect_tcp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
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{
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e_tcphdr th;
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proto_tree *tcp_tree = NULL, *field_tree = NULL;
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proto_item *ti, *tf;
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int offset = 0;
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gchar flags[64] = "<None>";
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gchar *fstr[] = {"FIN", "SYN", "RST", "PSH", "ACK", "URG", "ECN", "CWR" };
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gint fpos = 0, i;
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guint bpos;
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guint hlen;
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guint optlen;
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guint32 seglen;
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guint32 nxtseq;
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guint len;
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guint reported_len;
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vec_t cksum_vec[4];
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guint32 phdr[2];
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guint16 computed_cksum;
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guint length_remaining;
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if (check_col(pinfo->fd, COL_PROTOCOL))
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col_set_str(pinfo->fd, COL_PROTOCOL, "TCP");
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/* Clear out the Info column. */
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if (check_col(pinfo->fd, COL_INFO))
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col_clear(pinfo->fd, COL_INFO);
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/* Avoids alignment problems on many architectures. */
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tvb_memcpy(tvb, (guint8 *)&th, offset, sizeof(e_tcphdr));
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th.th_sport = ntohs(th.th_sport);
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th.th_dport = ntohs(th.th_dport);
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th.th_win = ntohs(th.th_win);
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th.th_sum = ntohs(th.th_sum);
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th.th_urp = ntohs(th.th_urp);
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th.th_seq = ntohl(th.th_seq);
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th.th_ack = ntohl(th.th_ack);
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/* Export the urgent pointer, for the benefit of protocols such as
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rlogin. */
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tcp_urgent_pointer = th.th_urp;
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if (check_col(pinfo->fd, COL_INFO) || tree) {
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for (i = 0; i < 8; i++) {
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bpos = 1 << i;
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if (th.th_flags & bpos) {
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if (fpos) {
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strcpy(&flags[fpos], ", ");
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fpos += 2;
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}
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strcpy(&flags[fpos], fstr[i]);
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fpos += 3;
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}
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}
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flags[fpos] = '\0';
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}
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hlen = hi_nibble(th.th_off_x2) * 4; /* TCP header length, in bytes */
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reported_len = tvb_reported_length(tvb);
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len = tvb_length(tvb);
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/* Compute the length of data in this segment. */
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seglen = reported_len - hlen;
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/* Compute the sequence number of next octet after this segment. */
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nxtseq = th.th_seq + seglen;
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if (check_col(pinfo->fd, COL_INFO)) {
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if (th.th_flags & TH_URG)
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col_append_fstr(pinfo->fd, COL_INFO, "%s > %s [%s] Seq=%u Ack=%u Win=%u Urg=%u Len=%d",
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get_tcp_port(th.th_sport), get_tcp_port(th.th_dport), flags,
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th.th_seq, th.th_ack, th.th_win, th.th_urp, seglen);
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else
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col_append_fstr(pinfo->fd, COL_INFO, "%s > %s [%s] Seq=%u Ack=%u Win=%u Len=%d",
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get_tcp_port(th.th_sport), get_tcp_port(th.th_dport), flags,
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th.th_seq, th.th_ack, th.th_win, seglen);
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}
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if (tree) {
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if (tcp_summary_in_tree) {
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ti = proto_tree_add_protocol_format(tree, proto_tcp, tvb, offset, hlen, "Transmission Control Protocol, Src Port: %s (%u), Dst Port: %s (%u), Seq: %u, Ack: %u", get_tcp_port(th.th_sport), th.th_sport, get_tcp_port(th.th_dport), th.th_dport, th.th_seq, th.th_ack);
|
|
}
|
|
else {
|
|
ti = proto_tree_add_item(tree, proto_tcp, tvb, offset, hlen, FALSE);
|
|
}
|
|
tcp_tree = proto_item_add_subtree(ti, ett_tcp);
|
|
proto_tree_add_uint_format(tcp_tree, hf_tcp_srcport, tvb, offset, 2, th.th_sport,
|
|
"Source port: %s (%u)", get_tcp_port(th.th_sport), th.th_sport);
|
|
proto_tree_add_uint_format(tcp_tree, hf_tcp_dstport, tvb, offset + 2, 2, th.th_dport,
|
|
"Destination port: %s (%u)", get_tcp_port(th.th_dport), th.th_dport);
|
|
proto_tree_add_uint_hidden(tcp_tree, hf_tcp_port, tvb, offset, 2, th.th_sport);
|
|
proto_tree_add_uint_hidden(tcp_tree, hf_tcp_port, tvb, offset + 2, 2, th.th_dport);
|
|
proto_tree_add_uint(tcp_tree, hf_tcp_seq, tvb, offset + 4, 4, th.th_seq);
|
|
if (nxtseq != th.th_seq)
|
|
proto_tree_add_uint(tcp_tree, hf_tcp_nxtseq, tvb, offset, 0, nxtseq);
|
|
if (th.th_flags & TH_ACK)
|
|
proto_tree_add_uint(tcp_tree, hf_tcp_ack, tvb, offset + 8, 4, th.th_ack);
|
|
proto_tree_add_uint_format(tcp_tree, hf_tcp_hdr_len, tvb, offset + 12, 1, hlen,
|
|
"Header length: %u bytes", hlen);
|
|
tf = proto_tree_add_uint_format(tcp_tree, hf_tcp_flags, tvb, offset + 13, 1,
|
|
th.th_flags, "Flags: 0x%04x (%s)", th.th_flags, flags);
|
|
field_tree = proto_item_add_subtree(tf, ett_tcp_flags);
|
|
proto_tree_add_boolean(field_tree, hf_tcp_flags_cwr, tvb, offset + 13, 1, th.th_flags);
|
|
proto_tree_add_boolean(field_tree, hf_tcp_flags_ecn, tvb, offset + 13, 1, th.th_flags);
|
|
proto_tree_add_boolean(field_tree, hf_tcp_flags_urg, tvb, offset + 13, 1, th.th_flags);
|
|
proto_tree_add_boolean(field_tree, hf_tcp_flags_ack, tvb, offset + 13, 1, th.th_flags);
|
|
proto_tree_add_boolean(field_tree, hf_tcp_flags_push, tvb, offset + 13, 1, th.th_flags);
|
|
proto_tree_add_boolean(field_tree, hf_tcp_flags_reset, tvb, offset + 13, 1, th.th_flags);
|
|
proto_tree_add_boolean(field_tree, hf_tcp_flags_syn, tvb, offset + 13, 1, th.th_flags);
|
|
proto_tree_add_boolean(field_tree, hf_tcp_flags_fin, tvb, offset + 13, 1, th.th_flags);
|
|
proto_tree_add_uint(tcp_tree, hf_tcp_window_size, tvb, offset + 14, 2, th.th_win);
|
|
if (!pinfo->fragmented && len >= reported_len) {
|
|
/* 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? */
|
|
|
|
/* Set up the fields of the pseudo-header. */
|
|
cksum_vec[0].ptr = pinfo->src.data;
|
|
cksum_vec[0].len = pinfo->src.len;
|
|
cksum_vec[1].ptr = pinfo->dst.data;
|
|
cksum_vec[1].len = pinfo->dst.len;
|
|
cksum_vec[2].ptr = (const guint8 *)&phdr;
|
|
switch (pinfo->src.type) {
|
|
|
|
case AT_IPv4:
|
|
phdr[0] = htonl((IP_PROTO_TCP<<16) + reported_len);
|
|
cksum_vec[2].len = 4;
|
|
break;
|
|
|
|
case AT_IPv6:
|
|
phdr[0] = htonl(reported_len);
|
|
phdr[1] = htonl(IP_PROTO_TCP);
|
|
cksum_vec[2].len = 8;
|
|
break;
|
|
|
|
default:
|
|
/* TCP runs only atop IPv4 and IPv6.... */
|
|
g_assert_not_reached();
|
|
break;
|
|
}
|
|
cksum_vec[3].ptr = tvb_get_ptr(tvb, offset, len);
|
|
cksum_vec[3].len = reported_len;
|
|
computed_cksum = in_cksum(&cksum_vec[0], 4);
|
|
if (computed_cksum == 0) {
|
|
proto_tree_add_uint_format(tcp_tree, hf_tcp_checksum, tvb,
|
|
offset + 16, 2, th.th_sum, "Checksum: 0x%04x (correct)", th.th_sum);
|
|
} else {
|
|
proto_tree_add_boolean_hidden(tcp_tree, hf_tcp_checksum_bad, tvb,
|
|
offset + 16, 2, TRUE);
|
|
proto_tree_add_uint_format(tcp_tree, hf_tcp_checksum, tvb,
|
|
offset + 16, 2, th.th_sum,
|
|
"Checksum: 0x%04x (incorrect, should be 0x%04x)", th.th_sum,
|
|
in_cksum_shouldbe(th.th_sum, computed_cksum));
|
|
}
|
|
} else {
|
|
proto_tree_add_uint_format(tcp_tree, hf_tcp_checksum, tvb,
|
|
offset + 16, 2, th.th_sum, "Checksum: 0x%04x", th.th_sum);
|
|
}
|
|
if (th.th_flags & TH_URG)
|
|
proto_tree_add_uint(tcp_tree, hf_tcp_urgent_pointer, tvb, offset + 18, 2, th.th_urp);
|
|
}
|
|
|
|
/* Decode TCP options, if any. */
|
|
if (tree && hlen > sizeof (e_tcphdr)) {
|
|
/* There's more than just the fixed-length header. Decode the
|
|
options. */
|
|
optlen = hlen - sizeof (e_tcphdr); /* length of options, in bytes */
|
|
tf = proto_tree_add_text(tcp_tree, tvb, offset + 20, optlen,
|
|
"Options: (%d bytes)", optlen);
|
|
field_tree = proto_item_add_subtree(tf, ett_tcp_options);
|
|
dissect_ip_tcp_options(tvb, offset + 20, optlen,
|
|
tcpopts, N_TCP_OPTS, TCPOPT_EOL, pinfo->fd, field_tree);
|
|
}
|
|
|
|
/* Skip over header + options */
|
|
offset += hlen;
|
|
|
|
pinfo->ptype = PT_TCP;
|
|
pinfo->srcport = th.th_sport;
|
|
pinfo->destport = th.th_dport;
|
|
|
|
/* Check the packet length to see if there's more data
|
|
(it could be an ACK-only packet) */
|
|
length_remaining = tvb_length_remaining(tvb, offset);
|
|
if (length_remaining != 0) {
|
|
if (th.th_flags & TH_RST) {
|
|
/*
|
|
* RFC1122 says:
|
|
*
|
|
* 4.2.2.12 RST Segment: RFC-793 Section 3.4
|
|
*
|
|
* A TCP SHOULD allow a received RST segment to include data.
|
|
*
|
|
* DISCUSSION
|
|
* It has been suggested that a RST segment could contain
|
|
* ASCII text that encoded and explained the cause of the
|
|
* RST. No standard has yet been established for such
|
|
* data.
|
|
*
|
|
* so for segments with RST we just display the data as text.
|
|
*/
|
|
proto_tree_add_text(tcp_tree, tvb, offset, length_remaining,
|
|
"Reset cause: %s",
|
|
tvb_format_text(tvb, offset, length_remaining));
|
|
} else
|
|
decode_tcp_ports( tvb, offset, pinfo, tree, th.th_sport, th.th_dport);
|
|
}
|
|
|
|
if( data_out_file ) {
|
|
reassemble_tcp( th.th_seq, /* sequence number */
|
|
seglen, /* data length */
|
|
tvb_get_ptr(tvb, offset, length_remaining), /* data */
|
|
length_remaining, /* captured data length */
|
|
( th.th_flags & TH_SYN ), /* is syn set? */
|
|
&pinfo->net_src,
|
|
&pinfo->net_dst,
|
|
pinfo->srcport,
|
|
pinfo->destport);
|
|
}
|
|
}
|
|
|
|
void
|
|
proto_register_tcp(void)
|
|
{
|
|
static hf_register_info hf[] = {
|
|
|
|
{ &hf_tcp_srcport,
|
|
{ "Source Port", "tcp.srcport", FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
"" }},
|
|
|
|
{ &hf_tcp_dstport,
|
|
{ "Destination Port", "tcp.dstport", FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
"" }},
|
|
|
|
{ &hf_tcp_port,
|
|
{ "Source or Destination Port", "tcp.port", FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
"" }},
|
|
|
|
{ &hf_tcp_seq,
|
|
{ "Sequence number", "tcp.seq", FT_UINT32, BASE_DEC, NULL, 0x0,
|
|
"" }},
|
|
|
|
{ &hf_tcp_nxtseq,
|
|
{ "Next sequence number", "tcp.nxtseq", FT_UINT32, BASE_DEC, NULL, 0x0,
|
|
"" }},
|
|
|
|
{ &hf_tcp_ack,
|
|
{ "Acknowledgement number", "tcp.ack", FT_UINT32, BASE_DEC, NULL, 0x0,
|
|
"" }},
|
|
|
|
{ &hf_tcp_hdr_len,
|
|
{ "Header Length", "tcp.hdr_len", FT_UINT8, BASE_DEC, NULL, 0x0,
|
|
"" }},
|
|
|
|
{ &hf_tcp_flags,
|
|
{ "Flags", "tcp.flags", FT_UINT8, BASE_HEX, NULL, 0x0,
|
|
"" }},
|
|
|
|
{ &hf_tcp_flags_cwr,
|
|
{ "Congestion Window Reduced (CWR)", "tcp.flags.cwr", FT_BOOLEAN, 8, TFS(&flags_set_truth), TH_CWR,
|
|
"" }},
|
|
|
|
{ &hf_tcp_flags_ecn,
|
|
{ "ECN-Echo", "tcp.flags.ecn", FT_BOOLEAN, 8, TFS(&flags_set_truth), TH_ECN,
|
|
"" }},
|
|
|
|
{ &hf_tcp_flags_urg,
|
|
{ "Urgent", "tcp.flags.urg", FT_BOOLEAN, 8, TFS(&flags_set_truth), TH_URG,
|
|
"" }},
|
|
|
|
{ &hf_tcp_flags_ack,
|
|
{ "Acknowledgment", "tcp.flags.ack", FT_BOOLEAN, 8, TFS(&flags_set_truth), TH_ACK,
|
|
"" }},
|
|
|
|
{ &hf_tcp_flags_push,
|
|
{ "Push", "tcp.flags.push", FT_BOOLEAN, 8, TFS(&flags_set_truth), TH_PUSH,
|
|
"" }},
|
|
|
|
{ &hf_tcp_flags_reset,
|
|
{ "Reset", "tcp.flags.reset", FT_BOOLEAN, 8, TFS(&flags_set_truth), TH_RST,
|
|
"" }},
|
|
|
|
{ &hf_tcp_flags_syn,
|
|
{ "Syn", "tcp.flags.syn", FT_BOOLEAN, 8, TFS(&flags_set_truth), TH_SYN,
|
|
"" }},
|
|
|
|
{ &hf_tcp_flags_fin,
|
|
{ "Fin", "tcp.flags.fin", FT_BOOLEAN, 8, TFS(&flags_set_truth), TH_FIN,
|
|
"" }},
|
|
|
|
{ &hf_tcp_window_size,
|
|
{ "Window size", "tcp.window_size", FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
"" }},
|
|
|
|
{ &hf_tcp_checksum,
|
|
{ "Checksum", "tcp.checksum", FT_UINT16, BASE_HEX, NULL, 0x0,
|
|
"" }},
|
|
|
|
{ &hf_tcp_checksum_bad,
|
|
{ "Bad Checksum", "tcp.checksum_bad", FT_BOOLEAN, BASE_NONE, NULL, 0x0,
|
|
"" }},
|
|
|
|
{ &hf_tcp_urgent_pointer,
|
|
{ "Urgent pointer", "tcp.urgent_pointer", FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
"" }},
|
|
};
|
|
static gint *ett[] = {
|
|
&ett_tcp,
|
|
&ett_tcp_flags,
|
|
&ett_tcp_options,
|
|
&ett_tcp_option_sack,
|
|
};
|
|
module_t *tcp_module;
|
|
|
|
proto_tcp = proto_register_protocol("Transmission Control Protocol",
|
|
"TCP", "tcp");
|
|
proto_register_field_array(proto_tcp, hf, array_length(hf));
|
|
proto_register_subtree_array(ett, array_length(ett));
|
|
|
|
/* subdissector code */
|
|
subdissector_table = register_dissector_table("tcp.port");
|
|
register_heur_dissector_list("tcp", &heur_subdissector_list);
|
|
register_conv_dissector_list("tcp", &conv_subdissector_list);
|
|
|
|
/* Register configuration preferences */
|
|
tcp_module = prefs_register_protocol(proto_tcp, NULL);
|
|
prefs_register_bool_preference(tcp_module, "tcp_summary_in_tree",
|
|
"Show TCP summary in protocol tree",
|
|
"Whether the TCP summary line should be shown in the protocol tree",
|
|
&tcp_summary_in_tree);
|
|
}
|
|
|
|
void
|
|
proto_reg_handoff_tcp(void)
|
|
{
|
|
dissector_add("ip.proto", IP_PROTO_TCP, dissect_tcp, proto_tcp);
|
|
}
|