/* packet-tcp.c
* Routines for TCP packet disassembly
*
- * $Id: packet-tcp.c,v 1.10 1998/12/21 03:43:29 gerald Exp $
+ * $Id: packet-tcp.c,v 1.96 2001/01/09 05:53:20 guy Exp $
*
* Ethereal - Network traffic analyzer
* By Gerald Combs <gerald@zing.org>
# include "config.h"
#endif
-#include <gtk/gtk.h>
-
-#include <stdio.h>
-
#ifdef HAVE_SYS_TYPES_H
# include <sys/types.h>
#endif
# include <netinet/in.h>
#endif
-#include "ethereal.h"
-#include "packet.h"
+#include <stdio.h>
+#include <string.h>
+#include <glib.h>
+#include "in_cksum.h"
+
+#ifdef NEED_SNPRINTF_H
+# include "snprintf.h"
+#endif
+
+#include "globals.h"
#include "resolv.h"
#include "follow.h"
+#include "prefs.h"
+#include "plugins.h"
+#include "packet-tcp.h"
+#include "packet-ip.h"
+#include "conversation.h"
+#include "strutil.h"
+
+/* Place TCP summary in proto tree */
+static gboolean tcp_summary_in_tree = TRUE;
extern FILE* data_out_file;
-extern packet_info pi;
-static gchar info_str[COL_MAX_LEN];
-static int info_len;
+guint16 tcp_urgent_pointer;
+
+static int proto_tcp = -1;
+static int hf_tcp_srcport = -1;
+static int hf_tcp_dstport = -1;
+static int hf_tcp_port = -1;
+static int hf_tcp_seq = -1;
+static int hf_tcp_nxtseq = -1;
+static int hf_tcp_ack = -1;
+static int hf_tcp_hdr_len = -1;
+static int hf_tcp_flags = -1;
+static int hf_tcp_flags_cwr = -1;
+static int hf_tcp_flags_ecn = -1;
+static int hf_tcp_flags_urg = -1;
+static int hf_tcp_flags_ack = -1;
+static int hf_tcp_flags_push = -1;
+static int hf_tcp_flags_reset = -1;
+static int hf_tcp_flags_syn = -1;
+static int hf_tcp_flags_fin = -1;
+static int hf_tcp_window_size = -1;
+static int hf_tcp_checksum = -1;
+static int hf_tcp_urgent_pointer = -1;
+
+static gint ett_tcp = -1;
+static gint ett_tcp_flags = -1;
+static gint ett_tcp_options = -1;
+static gint ett_tcp_option_sack = -1;
+
+static dissector_table_t subdissector_table;
+static heur_dissector_list_t heur_subdissector_list;
+static conv_dissector_list_t conv_subdissector_list;
+
+/* TCP Ports */
+
+#define TCP_PORT_SMTP 25
+
+/* TCP structs and definitions */
+
+typedef struct _e_tcphdr {
+ guint16 th_sport;
+ guint16 th_dport;
+ guint32 th_seq;
+ guint32 th_ack;
+ guint8 th_off_x2; /* combines th_off and th_x2 */
+ guint8 th_flags;
+#define TH_FIN 0x01
+#define TH_SYN 0x02
+#define TH_RST 0x04
+#define TH_PUSH 0x08
+#define TH_ACK 0x10
+#define TH_URG 0x20
+#define TH_ECN 0x40
+#define TH_CWR 0x80
+ guint16 th_win;
+ guint16 th_sum;
+ guint16 th_urp;
+} e_tcphdr;
+
+/*
+ * TCP option
+ */
+
+#define TCPOPT_NOP 1 /* Padding */
+#define TCPOPT_EOL 0 /* End of options */
+#define TCPOPT_MSS 2 /* Segment size negotiating */
+#define TCPOPT_WINDOW 3 /* Window scaling */
+#define TCPOPT_SACK_PERM 4 /* SACK Permitted */
+#define TCPOPT_SACK 5 /* SACK Block */
+#define TCPOPT_ECHO 6
+#define TCPOPT_ECHOREPLY 7
+#define TCPOPT_TIMESTAMP 8 /* Better RTT estimations/PAWS */
+#define TCPOPT_CC 11
+#define TCPOPT_CCNEW 12
+#define TCPOPT_CCECHO 13
+#define TCPOPT_MD5 19 /* RFC2385 */
+
+/*
+ * TCP option lengths
+ */
+
+#define TCPOLEN_MSS 4
+#define TCPOLEN_WINDOW 3
+#define TCPOLEN_SACK_PERM 2
+#define TCPOLEN_SACK_MIN 2
+#define TCPOLEN_ECHO 6
+#define TCPOLEN_ECHOREPLY 6
+#define TCPOLEN_TIMESTAMP 10
+#define TCPOLEN_CC 6
+#define TCPOLEN_CCNEW 6
+#define TCPOLEN_CCECHO 6
+#define TCPOLEN_MD5 18
static void
-tcp_info_append_uint(const char *abbrev, guint32 val) {
- int add_len = 0;
-
- if (info_len > 0)
- if(info_len > 0)
- add_len = snprintf(&info_str[info_len], COL_MAX_LEN - info_len, " %s=%u",
- abbrev, val);
- if (add_len > 0)
- info_len += add_len;
+tcp_info_append_uint(frame_data *fd, const char *abbrev, guint32 val)
+{
+ if (check_col(fd, COL_INFO))
+ col_append_fstr(fd, COL_INFO, " %s=%u", abbrev, val);
+}
static void
-dissect_tcpopt_maxseg(GtkWidget *opt_tree, const char *name, const u_char *opd,
- int offset, guint optlen)
+dissect_tcpopt_maxseg(const ip_tcp_opt *optp, tvbuff_t *tvb,
+ int offset, guint optlen, frame_data *fd, proto_tree *opt_tree)
{
- add_item_to_tree(opt_tree, offset, optlen,
- "%s: %u bytes", name, pntohs(opd));
- tcp_info_append_uint("MSS", pntohs(opd));
+ guint16 mss;
+
+ mss = tvb_get_ntohs(tvb, offset + 2);
+ proto_tree_add_text(opt_tree, tvb, offset, optlen,
+ "%s: %u bytes", optp->name, mss);
+ tcp_info_append_uint(fd, "MSS", mss);
}
static void
-dissect_tcpopt_wscale(GtkWidget *opt_tree, const char *name, const u_char *opd,
- int offset, guint optlen)
+dissect_tcpopt_wscale(const ip_tcp_opt *optp, tvbuff_t *tvb,
+ int offset, guint optlen, frame_data *fd, proto_tree *opt_tree)
{
- add_item_to_tree(opt_tree, offset, optlen,
- "%s: %u bytes", name, *opd);
- tcp_info_append_uint("WS", *opd);
+ guint8 ws;
+
+ ws = tvb_get_guint8(tvb, offset + 2);
+ proto_tree_add_text(opt_tree, tvb, offset, optlen,
+ "%s: %u bytes", optp->name, ws);
+ tcp_info_append_uint(fd, "WS", ws);
}
static void
-dissect_tcpopt_sack(GtkWidget *opt_tree, const char *name, const u_char *opd,
- int offset, guint optlen)
+dissect_tcpopt_sack(const ip_tcp_opt *optp, tvbuff_t *tvb,
+ int offset, guint optlen, frame_data *fd, proto_tree *opt_tree)
{
- int add_len = 0;
-
- GtkWidget *field_tree = NULL, *tf;
+ proto_tree *field_tree = NULL;
+ proto_item *tf;
guint leftedge, rightedge;
- tf = add_item_to_tree(opt_tree, offset, optlen, "%s:", name);
+ tf = proto_tree_add_text(opt_tree, tvb, offset, optlen, "%s:", optp->name);
offset += 2; /* skip past type and length */
optlen -= 2; /* subtract size of type and length */
while (optlen > 0) {
if (field_tree == NULL) {
/* Haven't yet made a subtree out of this option. Do so. */
- field_tree = gtk_tree_new();
- add_subtree(tf, field_tree, ETT_TCP_OPTION_SACK);
+ field_tree = proto_item_add_subtree(tf, *optp->subtree_index);
}
if (optlen < 4) {
- add_item_to_tree(field_tree, offset, optlen,
+ proto_tree_add_text(field_tree, tvb, offset, optlen,
"(suboption would go past end of option)");
break;
}
- /* XXX - check whether it goes past end of packet */
- leftedge = pntohl(opd);
- opd += 4;
+ leftedge = tvb_get_ntohl(tvb, offset);
optlen -= 4;
if (optlen < 4) {
- add_item_to_tree(field_tree, offset, optlen,
+ proto_tree_add_text(field_tree, tvb, offset, optlen,
"(suboption would go past end of option)");
break;
}
/* XXX - check whether it goes past end of packet */
- rightedge = pntohl(opd);
- opd += 4;
+ rightedge = tvb_get_ntohl(tvb, offset + 4);
optlen -= 4;
- add_item_to_tree(field_tree, offset, 8,
+ proto_tree_add_text(field_tree, tvb, offset, 8,
"left edge = %u, right edge = %u", leftedge, rightedge);
- tcp_info_append_uint("SLE", leftedge);
- tcp_info_append_uint("SRE", rightedge);
+ tcp_info_append_uint(fd, "SLE", leftedge);
+ tcp_info_append_uint(fd, "SRE", rightedge);
offset += 8;
}
}
static void
-dissect_tcpopt_echo(GtkWidget *opt_tree, const char *name, const u_char *opd,
- int offset, guint optlen)
+dissect_tcpopt_echo(const ip_tcp_opt *optp, tvbuff_t *tvb,
+ int offset, guint optlen, frame_data *fd, proto_tree *opt_tree)
{
- add_item_to_tree(opt_tree, offset, optlen,
- "%s: %u", name, pntohl(opd));
- tcp_info_append_uint("ECHO", pntohl(opd));
+ guint32 echo;
+
+ echo = tvb_get_ntohl(tvb, offset + 2);
+ proto_tree_add_text(opt_tree, tvb, offset, optlen,
+ "%s: %u", optp->name, echo);
+ tcp_info_append_uint(fd, "ECHO", echo);
}
static void
-dissect_tcpopt_timestamp(GtkWidget *opt_tree, const char *name,
- const u_char *opd, int offset, guint optlen)
+dissect_tcpopt_timestamp(const ip_tcp_opt *optp, tvbuff_t *tvb,
+ int offset, guint optlen, frame_data *fd, proto_tree *opt_tree)
{
- add_item_to_tree(opt_tree, offset, optlen,
- "%s: tsval %u, tsecr %u", name, pntohl(opd), pntohl(opd + 4));
- tcp_info_append_uint("TSV", pntohl(opd));
- tcp_info_append_uint("TSER", pntohl(opd + 4));
+ guint32 tsv, tser;
+
+ tsv = tvb_get_ntohl(tvb, offset + 2);
+ tser = tvb_get_ntohl(tvb, offset + 6);
+ proto_tree_add_text(opt_tree, tvb, offset, optlen,
+ "%s: tsval %u, tsecr %u", optp->name, tsv, tser);
+ tcp_info_append_uint(fd, "TSV", tsv);
+ tcp_info_append_uint(fd, "TSER", tser);
}
static void
-dissect_tcpopt_cc(GtkWidget *opt_tree, const char *name, const u_char *opd,
- int offset, guint optlen)
+dissect_tcpopt_cc(const ip_tcp_opt *optp, tvbuff_t *tvb,
+ int offset, guint optlen, frame_data *fd, proto_tree *opt_tree)
{
- add_item_to_tree(opt_tree, offset, optlen,
- "%s: %u", name, pntohl(opd));
- tcp_info_append_uint("CC", pntohl(opd));
+ guint32 cc;
+
+ cc = tvb_get_ntohl(tvb, offset + 2);
+ proto_tree_add_text(opt_tree, tvb, offset, optlen,
+ "%s: %u", optp->name, cc);
+ tcp_info_append_uint(fd, "CC", cc);
}
-static ip_tcp_opt tcpopts[] = {
+static const ip_tcp_opt tcpopts[] = {
{
TCPOPT_EOL,
"EOL",
+ NULL,
NO_LENGTH,
0,
NULL,
{
TCPOPT_NOP,
"NOP",
+ NULL,
NO_LENGTH,
0,
NULL,
{
TCPOPT_MSS,
"Maximum segment size",
+ NULL,
FIXED_LENGTH,
TCPOLEN_MSS,
dissect_tcpopt_maxseg
{
TCPOPT_WINDOW,
"Window scale",
+ NULL,
FIXED_LENGTH,
TCPOLEN_WINDOW,
dissect_tcpopt_wscale
{
TCPOPT_SACK_PERM,
"SACK permitted",
+ NULL,
FIXED_LENGTH,
TCPOLEN_SACK_PERM,
NULL,
{
TCPOPT_SACK,
"SACK",
+ &ett_tcp_option_sack,
VARIABLE_LENGTH,
TCPOLEN_SACK_MIN,
dissect_tcpopt_sack
{
TCPOPT_ECHO,
"Echo",
+ NULL,
FIXED_LENGTH,
TCPOLEN_ECHO,
dissect_tcpopt_echo
{
TCPOPT_ECHOREPLY,
"Echo reply",
+ NULL,
FIXED_LENGTH,
TCPOLEN_ECHOREPLY,
dissect_tcpopt_echo
{
TCPOPT_TIMESTAMP,
"Time stamp",
+ NULL,
FIXED_LENGTH,
TCPOLEN_TIMESTAMP,
dissect_tcpopt_timestamp
{
TCPOPT_CC,
"CC",
+ NULL,
FIXED_LENGTH,
TCPOLEN_CC,
dissect_tcpopt_cc
{
TCPOPT_CCNEW,
"CC.NEW",
+ NULL,
FIXED_LENGTH,
TCPOPT_CCNEW,
dissect_tcpopt_cc
{
TCPOPT_CCECHO,
"CC.ECHO",
+ NULL,
FIXED_LENGTH,
TCPOLEN_CCECHO,
dissect_tcpopt_cc
+ },
+ {
+ TCPOPT_MD5,
+ "TCP MD5 signature",
+ NULL,
+ FIXED_LENGTH,
+ TCPOLEN_MD5,
+ NULL
}
};
#define N_TCP_OPTS (sizeof tcpopts / sizeof tcpopts[0])
+/* TCP flags flag */
+static const true_false_string flags_set_truth = {
+ "Set",
+ "Not set"
+};
+
+
+/* Determine if there is a sub-dissector and call it. This has been */
+/* separated into a stand alone routine to other protocol dissectors */
+/* can call to it, ie. socks */
+
void
-dissect_tcp(const u_char *pd, int offset, frame_data *fd, GtkTree *tree) {
+decode_tcp_ports(tvbuff_t *tvb, int offset, packet_info *pinfo,
+ proto_tree *tree, int src_port, int dst_port)
+{
+ tvbuff_t *next_tvb;
+#ifdef HAVE_PLUGINS
+ const u_char *next_pd;
+ int next_offset;
+#endif
+
+ next_tvb = tvb_new_subset(tvb, offset, -1, -1);
+
+/* determine if this packet is part of a conversation and call dissector */
+/* for the conversation if available */
+
+ if (try_conversation_dissector(&pinfo->src, &pinfo->dst, PT_TCP,
+ src_port, dst_port, next_tvb, pinfo, tree))
+ return;
+
+ /* try to apply the plugins */
+#ifdef HAVE_PLUGINS
+ {
+ plugin *pt_plug = plugin_list;
+
+ if (enabled_plugins_number > 0) {
+ tvb_compat(next_tvb, &next_pd, &next_offset);
+ while (pt_plug) {
+ if (pt_plug->enabled && strstr(pt_plug->protocol, "tcp") &&
+ tree && dfilter_apply(pt_plug->filter, tree, next_pd, pinfo->fd->cap_len)) {
+ pt_plug->dissector(next_pd, next_offset, pinfo->fd, tree);
+ return;
+ }
+ pt_plug = pt_plug->next;
+ }
+ }
+ }
+#endif
+
+ /* do lookup with the subdissector table */
+ if (dissector_try_port(subdissector_table, src_port, next_tvb, pinfo, tree) ||
+ dissector_try_port(subdissector_table, dst_port, next_tvb, pinfo, tree))
+ return;
+
+ /* do lookup with the heuristic subdissector table */
+ if (dissector_try_heuristic(heur_subdissector_list, next_tvb, pinfo, tree))
+ return;
+
+ /* Oh, well, we don't know this; dissect it as data. */
+ dissect_data(next_tvb, 0, pinfo, tree);
+}
+
+
+static void
+dissect_tcp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+{
e_tcphdr th;
- GtkWidget *tcp_tree, *ti, *field_tree = NULL, *tf;
+ proto_tree *tcp_tree = NULL, *field_tree = NULL;
+ proto_item *ti, *tf;
+ int offset = 0;
gchar flags[64] = "<None>";
- gchar *fstr[] = {"FIN", "SYN", "RST", "PSH", "ACK", "URG"};
+ gchar *fstr[] = {"FIN", "SYN", "RST", "PSH", "ACK", "URG", "ECN", "CWR" };
gint fpos = 0, i;
guint bpos;
guint hlen;
guint optlen;
+ guint32 seglen;
+ guint32 nxtseq;
+ guint len;
+ guint reported_len;
+ vec_t cksum_vec[4];
+ guint32 phdr[2];
+ guint16 computed_cksum;
+ guint length_remaining;
+
+ CHECK_DISPLAY_AS_DATA(proto_tcp, tvb, pinfo, tree);
+
+ pinfo->current_proto = "TCP";
+
+ if (check_col(pinfo->fd, COL_PROTOCOL))
+ col_set_str(pinfo->fd, COL_PROTOCOL, "TCP");
+
+ /* Clear out the Info column. */
+ if (check_col(pinfo->fd, COL_INFO))
+ col_clear(pinfo->fd, COL_INFO);
- /* To do: Check for {cap len,pkt len} < struct len */
/* Avoids alignment problems on many architectures. */
- memcpy(&th, &pd[offset], sizeof(e_tcphdr));
+ tvb_memcpy(tvb, (guint8 *)&th, offset, sizeof(e_tcphdr));
th.th_sport = ntohs(th.th_sport);
th.th_dport = ntohs(th.th_dport);
th.th_win = ntohs(th.th_win);
th.th_urp = ntohs(th.th_urp);
th.th_seq = ntohl(th.th_seq);
th.th_ack = ntohl(th.th_ack);
-
- info_len = 0;
- if (check_col(fd, COL_PROTOCOL) || tree) {
- for (i = 0; i < 6; i++) {
+ /* Export the urgent pointer, for the benefit of protocols such as
+ rlogin. */
+ tcp_urgent_pointer = th.th_urp;
+
+ if (check_col(pinfo->fd, COL_INFO) || tree) {
+ for (i = 0; i < 8; i++) {
bpos = 1 << i;
if (th.th_flags & bpos) {
if (fpos) {
flags[fpos] = '\0';
}
- hlen = th.th_off * 4; /* TCP header length, in bytes */
-
- if (check_col(fd, COL_RES_SRC_PORT))
- col_add_str(fd, COL_RES_SRC_PORT, get_tcp_port(th.th_sport));
- if (check_col(fd, COL_UNRES_SRC_PORT))
- col_add_fstr(fd, COL_UNRES_SRC_PORT, "%u", th.th_sport);
- if (check_col(fd, COL_RES_DST_PORT))
- col_add_str(fd, COL_RES_DST_PORT, get_tcp_port(th.th_dport));
- if (check_col(fd, COL_UNRES_DST_PORT))
- col_add_fstr(fd, COL_UNRES_DST_PORT, "%u", th.th_dport);
- if (check_col(fd, COL_PROTOCOL))
- col_add_str(fd, COL_PROTOCOL, "TCP");
- if (check_col(fd, COL_INFO)) {
- /* Copy the data into info_str in case one of the option handling
- routines needs to append to it. */
+ hlen = hi_nibble(th.th_off_x2) * 4; /* TCP header length, in bytes */
+
+ reported_len = tvb_reported_length(tvb);
+ len = tvb_length(tvb);
+
+ /* Compute the length of data in this segment. */
+ seglen = reported_len - hlen;
+
+ /* Compute the sequence number of next octet after this segment. */
+ nxtseq = th.th_seq + seglen;
+
+ if (check_col(pinfo->fd, COL_INFO)) {
if (th.th_flags & TH_URG)
- info_len = snprintf(info_str, COL_MAX_LEN, "%s > %s [%s] Seq=%u Ack=%u Win=%u Urg=%u",
+ col_append_fstr(pinfo->fd, COL_INFO, "%s > %s [%s] Seq=%u Ack=%u Win=%u Urg=%u Len=%d",
get_tcp_port(th.th_sport), get_tcp_port(th.th_dport), flags,
- th.th_seq, th.th_ack, th.th_win, th.th_urp);
+ th.th_seq, th.th_ack, th.th_win, th.th_urp, seglen);
else
- info_len = snprintf(info_str, COL_MAX_LEN, "%s > %s [%s] Seq=%u Ack=%u Win=%u",
+ col_append_fstr(pinfo->fd, COL_INFO, "%s > %s [%s] Seq=%u Ack=%u Win=%u Len=%d",
get_tcp_port(th.th_sport), get_tcp_port(th.th_dport), flags,
- th.th_seq, th.th_ack, th.th_win);
- /* The info column is actually written after the options are decoded */
+ th.th_seq, th.th_ack, th.th_win, seglen);
}
if (tree) {
- ti = add_item_to_tree(GTK_WIDGET(tree), offset, hlen,
- "Transmission Control Protocol");
- tcp_tree = gtk_tree_new();
- add_subtree(ti, tcp_tree, ETT_TCP);
- add_item_to_tree(tcp_tree, offset, 2, "Source port: %s (%u)",
- get_tcp_port(th.th_sport), th.th_sport);
- add_item_to_tree(tcp_tree, offset + 2, 2, "Destination port: %s (%u)",
- get_tcp_port(th.th_dport), th.th_dport);
- add_item_to_tree(tcp_tree, offset + 4, 4, "Sequence number: %u",
- th.th_seq);
+ if (tcp_summary_in_tree) {
+ 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)
- add_item_to_tree(tcp_tree, offset + 8, 4, "Acknowledgement number: %u",
- th.th_ack);
- add_item_to_tree(tcp_tree, offset + 12, 1, "Header length: %u bytes", hlen);
- add_item_to_tree(tcp_tree, offset + 13, 1, "Flags: %s", flags);
- add_item_to_tree(tcp_tree, offset + 14, 2, "Window size: %u", th.th_win);
- add_item_to_tree(tcp_tree, offset + 16, 2, "Checksum: 0x%04x", th.th_sum);
+ 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_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)
- add_item_to_tree(tcp_tree, offset + 18, 2, "Urgent pointer: 0x%04x",
- th.th_urp);
+ proto_tree_add_uint(tcp_tree, hf_tcp_urgent_pointer, tvb, offset + 18, 2, th.th_urp);
}
/* Decode TCP options, if any. */
- if (hlen > sizeof (e_tcphdr)) {
+ 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 */
- if (tree) {
- tf = add_item_to_tree(tcp_tree, offset + 20, optlen,
- "Options: (%d bytes)", optlen);
- field_tree = gtk_tree_new();
- add_subtree(tf, field_tree, ETT_TCP_OPTIONS);
- }
- dissect_ip_tcp_options(field_tree, &pd[offset + 20], offset + 20, optlen,
- tcpopts, N_TCP_OPTS, TCPOPT_EOL);
+ 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);
}
- if (check_col(fd, COL_INFO))
- col_add_str(fd, COL_INFO, info_str);
-
/* Skip over header + options */
offset += hlen;
- /* until we decode those options, I'll check the packet length
- to see if there's more data. -- gilbert */
- if (fd->cap_len > offset) {
- switch(MIN(th.th_sport, th.th_dport)) {
- case TCP_PORT_PRINTER:
- dissect_lpd(pd, offset, fd, tree);
- break;
- default:
- /* check existence of high level protocols */
-
- if (memcmp(&pd[offset], "GIOP", 4) == 0) {
- dissect_giop(pd, offset, fd, tree);
- }
- else {
- dissect_data(pd, offset, fd, tree);
- }
- }
+ 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);
}
- pi.srcport = th.th_sport;
- pi.destport = th.th_dport;
-
if( data_out_file ) {
- reassemble_tcp( th.th_seq, /* sequence number */
- ( pi.iplen -( pi.iphdrlen * 4 )-( th.th_off * 4 ) ), /* length */
- ( pd+offset ), /* data */
- ( th.th_flags & 0x02 ), /* is syn set? */
- pi.ip_src ); /* src ip */
+ 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_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);
+}
git.samba.org / obnox / wireshark / wip.git / blobdiff