wireshark/epan/dissectors/packet-wtp.c

1071 lines
39 KiB
C

/* packet-wtp.c
*
* Routines to dissect WTP component of WAP traffic.
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* WAP dissector based on original work by Ben Fowler
* Updated by Neil Hunter <neil.hunter@energis-squared.com>
* WTLS support by Alexandre P. Ferreira (Splice IP)
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "config.h"
#ifdef DEBUG
#include <stdio.h>
#endif
#include <epan/packet.h>
#include <epan/reassemble.h>
#include "packet-wap.h"
#include "packet-wtp.h"
#include "packet-wsp.h"
void proto_register_wtp(void);
void proto_reg_handoff_wtp(void);
static const true_false_string continue_truth = {
"TPI Present" ,
"No TPI"
};
static const true_false_string RID_truth = {
"Re-Transmission",
"First transmission"
};
static const true_false_string TIDNew_truth = {
"TID is new" ,
"TID is valid"
};
static const true_false_string tid_response_truth = {
"Response" ,
"Original"
};
static const true_false_string UP_truth = {
"User Acknowledgement required" ,
"User Acknowledgement optional"
};
static const true_false_string TVETOK_truth = {
"True",
"False"
};
static const value_string vals_wtp_pdu_type[] = {
{ 0, "Not Allowed" },
{ 1, "Invoke" },
{ 2, "Result" },
{ 3, "Ack" },
{ 4, "Abort" },
{ 5, "Segmented Invoke" },
{ 6, "Segmented Result" },
{ 7, "Negative Ack" },
{ 0, NULL }
};
static const value_string vals_transaction_trailer[] = {
{ 0, "Not last packet" },
{ 1, "Last packet of message" },
{ 2, "Last packet of group" },
{ 3, "Re-assembly not supported" },
{ 0, NULL }
};
static const value_string vals_version[] = {
{ 0, "Current" },
{ 1, "Undefined" },
{ 2, "Undefined" },
{ 3, "Undefined" },
{ 0, NULL }
};
static const value_string vals_abort_type[] = {
{ 0, "Provider" },
{ 1, "User (WSP)" },
{ 0, NULL }
};
static const value_string vals_abort_reason_provider[] = {
{ 0x00, "Unknown" },
{ 0x01, "Protocol Error" },
{ 0x02, "Invalid TID" },
{ 0x03, "Not Implemented Class 2" },
{ 0x04, "Not Implemented SAR" },
{ 0x05, "Not Implemented User Acknowledgement" },
{ 0x06, "WTP Version Zero" },
{ 0x07, "Capacity Temporarily Exceeded" },
{ 0x08, "No Response" },
{ 0x09, "Message Too Large" },
{ 0x00, NULL }
};
static const value_string vals_transaction_classes[] = {
{ 0x00, "Unreliable Invoke without Result" },
{ 0x01, "Reliable Invoke without Result" },
{ 0x02, "Reliable Invoke with Reliable Result" },
{ 0x00, NULL }
};
static const value_string vals_tpi_type[] = {
{ 0x00, "Error" },
{ 0x01, "Info" },
{ 0x02, "Option" },
{ 0x03, "Packet sequence number" },
{ 0x04, "SDU boundary" },
{ 0x05, "Frame boundary" },
{ 0x00, NULL }
};
static const value_string vals_tpi_opt[] = {
{ 0x01, "Maximum receive unit" },
{ 0x02, "Total message size" },
{ 0x03, "Delay transmission timer" },
{ 0x04, "Maximum group" },
{ 0x05, "Current TID" },
{ 0x06, "No cached TID" },
{ 0x00, NULL }
};
/* File scoped variables for the protocol and registered fields */
static int proto_wtp = -1;
/* These fields used by fixed part of header */
static int hf_wtp_header_sub_pdu_size = -1;
static int hf_wtp_header_flag_continue = -1;
static int hf_wtp_header_pdu_type = -1;
static int hf_wtp_header_flag_Trailer = -1;
static int hf_wtp_header_flag_RID = -1;
static int hf_wtp_header_flag_TID = -1;
static int hf_wtp_header_flag_TID_response = -1;
/* These fields used by Invoke packets */
static int hf_wtp_header_Inv_version = -1;
static int hf_wtp_header_Inv_flag_TIDNew = -1;
static int hf_wtp_header_Inv_flag_UP = -1;
static int hf_wtp_header_Inv_Reserved = -1;
static int hf_wtp_header_Inv_TransactionClass = -1;
/* static int hf_wtp_header_variable_part = -1; */
/* static int hf_wtp_data = -1; */
static int hf_wtp_tpi_type = -1;
static int hf_wtp_tpi_psn = -1;
static int hf_wtp_tpi_opt = -1;
static int hf_wtp_tpi_optval = -1;
static int hf_wtp_tpi_info = -1;
static int hf_wtp_header_Ack_flag_TVETOK = -1;
static int hf_wtp_header_Abort_type = -1;
static int hf_wtp_header_Abort_reason_provider = -1;
static int hf_wtp_header_Abort_reason_user = -1;
static int hf_wtp_header_sequence_number = -1;
static int hf_wtp_header_missing_packets = -1;
static int hf_wtp_payload = -1;
/* These fields used when reassembling WTP fragments */
static int hf_wtp_fragments = -1;
static int hf_wtp_fragment = -1;
static int hf_wtp_fragment_overlap = -1;
static int hf_wtp_fragment_overlap_conflict = -1;
static int hf_wtp_fragment_multiple_tails = -1;
static int hf_wtp_fragment_too_long_fragment = -1;
static int hf_wtp_fragment_error = -1;
static int hf_wtp_fragment_count = -1;
static int hf_wtp_reassembled_in = -1;
static int hf_wtp_reassembled_length = -1;
/* Initialize the subtree pointers */
static gint ett_wtp = -1;
static gint ett_wtp_sub_pdu_tree = -1;
static gint ett_header = -1;
static gint ett_tpilist = -1;
static gint ett_wsp_fragments = -1;
static gint ett_wtp_fragment = -1;
static const fragment_items wtp_frag_items = {
&ett_wtp_fragment,
&ett_wsp_fragments,
&hf_wtp_fragments,
&hf_wtp_fragment,
&hf_wtp_fragment_overlap,
&hf_wtp_fragment_overlap_conflict,
&hf_wtp_fragment_multiple_tails,
&hf_wtp_fragment_too_long_fragment,
&hf_wtp_fragment_error,
&hf_wtp_fragment_count,
&hf_wtp_reassembled_in,
&hf_wtp_reassembled_length,
/* Reassembled data field */
NULL,
"fragments"
};
/* Handle for WSP dissector */
static dissector_handle_t wsp_handle;
static dissector_handle_t wtp_fromudp_handle;
/*
* reassembly of WSP
*/
static reassembly_table wtp_reassembly_table;
/*
* Extract some bitfields
*/
#define pdu_type(octet) (((octet) >> 3) & 0x0F) /* Note pdu type must not be 0x00 */
#define transaction_class(octet) ((octet) & 0x03) /* ......XX */
#define transmission_trailer(octet) (((octet) >> 1) & 0x01) /* ......X. */
static char retransmission_indicator(unsigned char octet)
{
switch (pdu_type(octet)) {
case INVOKE:
case RESULT:
case ACK:
case SEGMENTED_INVOKE:
case SEGMENTED_RESULT:
case NEGATIVE_ACK:
return octet & 0x01; /* .......X */
default:
return 0;
}
}
/*
* dissect a TPI
*/
static void
wtp_handle_tpi(proto_tree *tree, tvbuff_t *tvb)
{
int offset = 0;
unsigned char tByte;
unsigned char tType;
unsigned char tLen;
proto_tree *subTree = NULL;
proto_item *pi;
tByte = tvb_get_guint8(tvb, offset++);
tType = (tByte & 0x78) >> 3;
if (tByte & 0x04) /* Long TPI */
tLen = tvb_get_guint8(tvb, offset++);
else
tLen = tByte & 0x03;
pi = proto_tree_add_uint(tree, hf_wtp_tpi_type,
tvb, 0, tvb_captured_length(tvb), tType);
subTree = proto_item_add_subtree(pi, ett_tpilist);
switch (tType) {
case 0x00: /* Error*/
/* \todo */
break;
case 0x01: /* Info */
/* Beware, untested case here */
proto_tree_add_item(subTree, hf_wtp_tpi_info,
tvb, offset, tLen, ENC_NA);
break;
case 0x02: /* Option */
proto_tree_add_item(subTree, hf_wtp_tpi_opt,
tvb, offset++, 1, ENC_LITTLE_ENDIAN);
proto_tree_add_item(subTree, hf_wtp_tpi_optval,
tvb, offset, tLen - 1, ENC_NA);
break;
case 0x03: /* PSN */
proto_tree_add_item(subTree, hf_wtp_tpi_psn,
tvb, offset, 1, ENC_LITTLE_ENDIAN);
break;
case 0x04: /* SDU boundary */
/* \todo */
break;
case 0x05: /* Frame boundary */
/* \todo */
break;
default:
break;
}
}
/* Code to actually dissect the packets */
static void
dissect_wtp_common(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
char *szInfo;
int offCur = 0; /* current offset from start of WTP data */
gint returned_length, str_index = 0;
unsigned char b0;
/* continuation flag */
unsigned char fCon; /* Continue flag */
unsigned char fRID; /* Re-transmission indicator*/
unsigned char fTTR = '\0'; /* Transmission trailer */
guint cbHeader = 0; /* Fixed header length */
guint vHeader = 0; /* Variable header length*/
int abortType = 0;
/* Set up structures we'll need to add the protocol subtree and manage it */
proto_item *ti = NULL;
proto_tree *wtp_tree = NULL;
char pdut;
char clsTransaction = 3;
int numMissing = 0; /* Number of missing packets in a negative ack */
int i;
tvbuff_t *wsp_tvb = NULL;
guint8 psn = 0; /* Packet sequence number*/
guint16 TID = 0; /* Transaction-Id */
int dataOffset;
gint dataLen;
#define SZINFO_SIZE 256
szInfo=(char *)wmem_alloc(wmem_packet_scope(), SZINFO_SIZE);
b0 = tvb_get_guint8 (tvb, offCur + 0);
/* Discover Concatenated PDUs */
if (b0 == 0) {
guint c_fieldlen = 0; /* Length of length-field */
guint c_pdulen = 0; /* Length of conc. PDU */
if (tree) {
ti = proto_tree_add_item(tree, proto_wtp,
tvb, offCur, 1, ENC_NA);
wtp_tree = proto_item_add_subtree(ti, ett_wtp_sub_pdu_tree);
proto_item_append_text(ti, ", PDU concatenation");
}
offCur = 1;
i = 1;
while (offCur < (int) tvb_reported_length(tvb)) {
tvbuff_t *wtp_tvb;
/* The length of an embedded WTP PDU is coded as either:
* - a 7-bit value contained in one octet with highest bit == 0.
* - a 15-bit value contained in two octets (little endian)
* if the 1st octet has its highest bit == 1.
* This means that this is NOT encoded as an uintvar-integer!!!
*/
b0 = tvb_get_guint8(tvb, offCur + 0);
if (b0 & 0x80) {
c_fieldlen = 2;
c_pdulen = ((b0 & 0x7f) << 8) | tvb_get_guint8(tvb, offCur + 1);
} else {
c_fieldlen = 1;
c_pdulen = b0;
}
if (tree) {
proto_tree_add_uint(wtp_tree, hf_wtp_header_sub_pdu_size,
tvb, offCur, c_fieldlen, c_pdulen);
}
if (i > 1) {
col_append_str(pinfo->cinfo, COL_INFO, ", ");
}
/* Skip the length field for the WTP sub-tvb */
wtp_tvb = tvb_new_subset_length(tvb, offCur + c_fieldlen, c_pdulen);
dissect_wtp_common(wtp_tvb, pinfo, wtp_tree);
offCur += c_fieldlen + c_pdulen;
i++;
}
if (tree) {
proto_item_append_text(ti, ", PDU count: %u", i);
}
return;
}
/* No concatenation */
fCon = b0 & 0x80;
fRID = retransmission_indicator(b0);
pdut = pdu_type(b0);
#ifdef DEBUG
proto_tree_add_debug_text(tree, "WTP packet %u: tree = %p, pdu = %s (%u) length: %u\n",
pinfo->num, tree,
val_to_str(pdut, vals_wtp_pdu_type, "Unknown PDU type 0x%x"),
pdut, tvb_captured_length(tvb));
#endif
/* Develop the string to put in the Info column */
returned_length = g_snprintf(szInfo, SZINFO_SIZE, "WTP %s",
val_to_str(pdut, vals_wtp_pdu_type, "Unknown PDU type 0x%x"));
str_index += MIN(returned_length, SZINFO_SIZE-str_index);
switch (pdut) {
case INVOKE:
fTTR = transmission_trailer(b0);
TID = tvb_get_ntohs(tvb, offCur + 1);
psn = 0;
clsTransaction = transaction_class(tvb_get_guint8(tvb, offCur + 3));
returned_length = g_snprintf(&szInfo[str_index], SZINFO_SIZE-str_index,
" Class %d", clsTransaction);
str_index += MIN(returned_length, SZINFO_SIZE-str_index);
cbHeader = 4;
break;
case SEGMENTED_INVOKE:
case SEGMENTED_RESULT:
fTTR = transmission_trailer(b0);
TID = tvb_get_ntohs(tvb, offCur + 1);
psn = tvb_get_guint8(tvb, offCur + 3);
if (psn != 0) {
returned_length = g_snprintf(&szInfo[str_index], SZINFO_SIZE-str_index,
" (%u)", psn);
str_index += MIN(returned_length, SZINFO_SIZE-str_index);
}
cbHeader = 4;
break;
case ABORT:
cbHeader = 4;
break;
case RESULT:
fTTR = transmission_trailer(b0);
TID = tvb_get_ntohs(tvb, offCur + 1);
psn = 0;
cbHeader = 3;
break;
case ACK:
cbHeader = 3;
break;
case NEGATIVE_ACK:
/* Variable number of missing packets */
numMissing = tvb_get_guint8(tvb, offCur + 3);
cbHeader = numMissing + 4;
break;
default:
break;
};
if (fRID) {
/*returned_length =*/ g_snprintf(&szInfo[str_index], SZINFO_SIZE-str_index, " R" );
/*str_index += MIN(returned_length, SZINFO_SIZE-str_index);*/
};
/* In the interest of speed, if "tree" is NULL, don't do any work not
necessary to generate protocol tree items. */
if (tree) {
#ifdef DEBUG
fprintf(stderr, "dissect_wtp: cbHeader = %d\n", cbHeader);
#endif
/* NOTE - Length will be set when we process the TPI */
ti = proto_tree_add_item(tree, proto_wtp, tvb, offCur, -1, ENC_NA);
#ifdef DEBUG
fprintf(stderr, "dissect_wtp: (7) Returned from proto_tree_add_item\n");
#endif
wtp_tree = proto_item_add_subtree(ti, ett_wtp);
/* Code to process the packet goes here */
#ifdef DEBUG
fprintf(stderr, "dissect_wtp: cbHeader = %d\n", cbHeader);
fprintf(stderr, "dissect_wtp: offCur = %d\n", offCur);
#endif
/* Add common items: only CON and PDU Type */
proto_tree_add_item(
wtp_tree, /* tree */
hf_wtp_header_flag_continue, /* id */
tvb,
offCur, /* start of highlight */
1, /* length of highlight*/
b0 /* value */
);
proto_tree_add_item(wtp_tree, hf_wtp_header_pdu_type, tvb, offCur, 1, ENC_LITTLE_ENDIAN);
switch(pdut) {
case INVOKE:
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_Trailer, tvb, offCur, 1, ENC_LITTLE_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_RID, tvb, offCur, 1, ENC_LITTLE_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID_response, tvb, offCur + 1, 2, ENC_BIG_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID, tvb, offCur + 1, 2, ENC_BIG_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_Inv_version , tvb, offCur + 3, 1, ENC_LITTLE_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_Inv_flag_TIDNew, tvb, offCur + 3, 1, ENC_LITTLE_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_Inv_flag_UP, tvb, offCur + 3, 1, ENC_LITTLE_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_Inv_Reserved, tvb, offCur + 3, 1, ENC_LITTLE_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_Inv_TransactionClass, tvb, offCur + 3, 1, ENC_LITTLE_ENDIAN);
proto_item_append_text(ti,
", PDU: Invoke (%u)"
", Transaction Class: %s (%u)",
INVOKE,
val_to_str_const(clsTransaction, vals_transaction_classes, "Undefined"),
clsTransaction);
break;
case RESULT:
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_Trailer, tvb, offCur, 1, ENC_LITTLE_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_RID, tvb, offCur, 1, ENC_LITTLE_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID_response, tvb, offCur + 1, 2, ENC_BIG_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID, tvb, offCur + 1, 2, ENC_BIG_ENDIAN);
proto_item_append_text(ti, ", PDU: Result (%u)", RESULT);
break;
case ACK:
proto_tree_add_item(wtp_tree, hf_wtp_header_Ack_flag_TVETOK, tvb, offCur, 1, ENC_BIG_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_RID, tvb, offCur, 1, ENC_LITTLE_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID_response, tvb, offCur + 1, 2, ENC_BIG_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID, tvb, offCur + 1, 2, ENC_BIG_ENDIAN);
proto_item_append_text(ti, ", PDU: ACK (%u)", ACK);
break;
case ABORT:
abortType = tvb_get_guint8 (tvb, offCur) & 0x07;
proto_tree_add_item(wtp_tree, hf_wtp_header_Abort_type , tvb, offCur , 1, ENC_LITTLE_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID_response, tvb, offCur + 1, 2, ENC_BIG_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID, tvb, offCur + 1, 2, ENC_BIG_ENDIAN);
if (abortType == PROVIDER) {
guint8 reason = tvb_get_guint8(tvb, offCur + 3);
proto_tree_add_item( wtp_tree, hf_wtp_header_Abort_reason_provider , tvb, offCur + 3 , 1, ENC_LITTLE_ENDIAN);
proto_item_append_text(ti,
", PDU: Abort (%u)"
", Type: Provider (%u)"
", Reason: %s (%u)",
ABORT,
PROVIDER,
val_to_str_const(reason, vals_abort_reason_provider, "Undefined"),
reason);
}
else if (abortType == USER) {
guint8 reason = tvb_get_guint8(tvb, offCur + 3);
proto_tree_add_item(wtp_tree, hf_wtp_header_Abort_reason_user , tvb, offCur + 3 , 1, ENC_LITTLE_ENDIAN);
proto_item_append_text(ti,
", PDU: Abort (%u)"
", Type: User (%u)"
", Reason: %s (%u)",
ABORT,
PROVIDER,
val_to_str_ext_const(reason, &vals_wsp_reason_codes_ext, "Undefined"),
reason);
}
break;
case SEGMENTED_INVOKE:
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_Trailer, tvb, offCur, 1, ENC_LITTLE_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_RID, tvb, offCur, 1, ENC_LITTLE_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID_response, tvb, offCur + 1, 2, ENC_BIG_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID, tvb, offCur + 1, 2, ENC_BIG_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_sequence_number , tvb, offCur + 3, 1, ENC_LITTLE_ENDIAN);
proto_item_append_text(ti,
", PDU: Segmented Invoke (%u)"
", Packet Sequence Number: %u",
SEGMENTED_INVOKE, psn);
break;
case SEGMENTED_RESULT:
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_Trailer, tvb, offCur, 1, ENC_LITTLE_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_RID, tvb, offCur, 1, ENC_LITTLE_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID_response, tvb, offCur + 1, 2, ENC_BIG_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID, tvb, offCur + 1, 2, ENC_BIG_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_sequence_number , tvb, offCur + 3, 1, ENC_LITTLE_ENDIAN);
proto_item_append_text(ti,
", PDU: Segmented Result (%u)"
", Packet Sequence Number: %u",
SEGMENTED_RESULT, psn);
break;
case NEGATIVE_ACK:
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_RID, tvb, offCur, 1, ENC_LITTLE_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID_response, tvb, offCur + 1, 2, ENC_BIG_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID, tvb, offCur + 1, 2, ENC_BIG_ENDIAN);
proto_tree_add_item(wtp_tree, hf_wtp_header_missing_packets , tvb, offCur + 3, 1, ENC_LITTLE_ENDIAN);
/* Iterate through missing packets */
for (i = 0; i < numMissing; i++)
{
proto_tree_add_item(wtp_tree, hf_wtp_header_sequence_number, tvb, offCur + 4 + i, 1, ENC_LITTLE_ENDIAN);
}
proto_item_append_text(ti,
", PDU: Negative Ack (%u)"
", Missing Packets: %u",
NEGATIVE_ACK, numMissing);
break;
default:
break;
};
if (fRID) {
proto_item_append_text(ti, ", Retransmission");
}
} else { /* tree is NULL */
#ifdef DEBUG
fprintf(stderr, "dissect_wtp: (4) tree was %p\n", tree);
#endif
}
/* Process the variable part */
if (fCon) { /* Now, analyze variable part */
guint8 tCon;
guint8 tByte;
guint tpiLen;
tvbuff_t *tmp_tvb;
vHeader = 0; /* Start scan all over */
do {
tByte = tvb_get_guint8(tvb, offCur + cbHeader + vHeader);
tCon = tByte & 0x80;
if (tByte & 0x04) /* Long TPI */
tpiLen = 2 + tvb_get_guint8(tvb, offCur + cbHeader + vHeader + 1);
else
tpiLen = 1 + (tByte & 0x03);
if (tree)
{
tmp_tvb = tvb_new_subset_length(tvb, offCur + cbHeader + vHeader, tpiLen);
wtp_handle_tpi(wtp_tree, tmp_tvb);
}
vHeader += tpiLen;
} while (tCon);
} else {
/* There is no variable part */
} /* End of variable part of header */
/* Set the length of the WTP protocol part now we know the length of the
* fixed and variable WTP headers */
if (tree)
proto_item_set_len(ti, cbHeader + vHeader);
#ifdef DEBUG
fprintf( stderr, "dissect_wtp: cbHeader = %d\n", cbHeader );
#endif
/*
* Any remaining data ought to be WSP data (if not WTP ACK, NACK
* or ABORT pdu), so, if we have any remaining data, and it's
* not an ACK, NACK, or ABORT PDU, hand it off (defragmented) to the
* WSP dissector.
* Note that the last packet of a fragmented WTP message needn't
* contain any data, so we allow payloadless packets to be
* reassembled. (XXX - does the reassembly code handle this
* for packets other than the last packet?)
*
* Try calling a subdissector only if:
* - The WTP payload is ressembled in this very packet,
* - The WTP payload is not fragmented across packets.
*/
dataOffset = offCur + cbHeader + vHeader;
dataLen = tvb_reported_length_remaining(tvb, dataOffset);
if ((dataLen >= 0) &&
! ((pdut==ACK) || (pdut==NEGATIVE_ACK) || (pdut==ABORT)))
{
/* Try to reassemble if needed, and hand over to WSP
* A fragmented WTP packet is either:
* - An INVOKE with fTTR (transmission trailer) not set,
* - a SEGMENTED_INVOKE,
* - A RESULT with fTTR (transmission trailer) not set,
* - a SEGMENTED_RESULT.
*/
if ( ( (pdut == SEGMENTED_INVOKE) || (pdut == SEGMENTED_RESULT)
|| ( ((pdut == INVOKE) || (pdut == RESULT)) && (!fTTR) )
) && tvb_bytes_exist(tvb, dataOffset, dataLen) )
{
/* Try reassembling fragments */
fragment_head *fd_wtp = NULL;
guint32 reassembled_in = 0;
gboolean save_fragmented = pinfo->fragmented;
pinfo->fragmented = TRUE;
fd_wtp = fragment_add_seq(&wtp_reassembly_table, tvb, dataOffset,
pinfo, TID, NULL, psn, dataLen, !fTTR, 0);
/* XXX - fragment_add_seq() yields NULL unless Wireshark knows
* that the packet is part of a reassembled whole. This means
* that fd_wtp will be NULL as long as Wireshark did not encounter
* (and process) the packet containing the last fragment.
* This implies that Wireshark needs two passes over the data for
* correct reassembly. At the first pass, a capture containing
* three fragments plus a retransmssion of the last fragment
* will progressively show:
*
* Packet 1: (Unreassembled fragment 1)
* Packet 2: (Unreassembled fragment 2)
* Packet 3: (Reassembled WTP)
* Packet 4: (WTP payload reassembled in packet 3)
*
* However at subsequent evaluation (e.g., by applying a display
* filter) the packet summary will show:
*
* Packet 1: (WTP payload reassembled in packet 3)
* Packet 2: (WTP payload reassembled in packet 3)
* Packet 3: (Reassembled WTP)
* Packet 4: (WTP payload reassembled in packet 3)
*
* This is important to know, and also affects read filters!
*/
wsp_tvb = process_reassembled_data(tvb, dataOffset, pinfo,
"Reassembled WTP", fd_wtp, &wtp_frag_items,
NULL, wtp_tree);
#ifdef DEBUG
proto_tree_add_debug_text(tree, "WTP: Packet %u %s -> %d: wsp_tvb = %p, fd_wtp = %p, frame = %u\n",
pinfo->num,
fd_wtp ? "Reassembled" : "Not reassembled",
fd_wtp ? fd_wtp->reassembled_in : -1,
wsp_tvb,
fd_wtp
);
#endif
if (fd_wtp) {
/* Reassembled */
reassembled_in = fd_wtp->reassembled_in;
if (pinfo->num == reassembled_in) {
/* Reassembled in this very packet:
* We can safely hand the tvb to the WSP dissector */
call_dissector(wsp_handle, wsp_tvb, pinfo, tree);
} else {
/* Not reassembled in this packet */
col_append_fstr(pinfo->cinfo, COL_INFO,
"%s (WTP payload reassembled in packet %u)",
szInfo, fd_wtp->reassembled_in);
proto_tree_add_item(wtp_tree, hf_wtp_payload, tvb, dataOffset, -1, ENC_NA);
}
} else {
/* Not reassembled yet, or not reassembled at all */
col_append_fstr(pinfo->cinfo, COL_INFO,
"%s (Unreassembled fragment %u)",
szInfo, psn);
proto_tree_add_item(wtp_tree, hf_wtp_payload, tvb, dataOffset, -1, ENC_NA);
}
/* Now reset fragmentation information in pinfo */
pinfo->fragmented = save_fragmented;
}
else if ( ((pdut == INVOKE) || (pdut == RESULT)) && (fTTR) )
{
/* Non-fragmented payload */
wsp_tvb = tvb_new_subset_remaining(tvb, dataOffset);
/* We can safely hand the tvb to the WSP dissector */
call_dissector(wsp_handle, wsp_tvb, pinfo, tree);
}
else
{
/* Nothing to hand to subdissector */
col_append_str(pinfo->cinfo, COL_INFO, szInfo);
}
}
else
{
/* Nothing to hand to subdissector */
col_append_str(pinfo->cinfo, COL_INFO, szInfo);
}
}
/*
* Called directly from UDP.
* Put "WTP+WSP" into the "Protocol" column.
*/
static int
dissect_wtp_fromudp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
{
col_set_str(pinfo->cinfo, COL_PROTOCOL, "WTP+WSP");
col_clear(pinfo->cinfo, COL_INFO);
dissect_wtp_common(tvb, pinfo, tree);
return tvb_captured_length(tvb);
}
/*
* Called from a higher-level WAP dissector, presumably WTLS.
* Put "WTLS+WSP+WTP" to the "Protocol" column.
*
* XXX - is this supposed to be called from WTLS? If so, we're not
* calling it....
*
* XXX - can this be called from any other dissector?
*/
static int
dissect_wtp_fromwtls(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
{
col_set_str(pinfo->cinfo, COL_PROTOCOL, "WTLS+WTP+WSP");
col_clear(pinfo->cinfo, COL_INFO);
dissect_wtp_common(tvb, pinfo, tree);
return tvb_captured_length(tvb);
}
/* Register the protocol with Wireshark */
void
proto_register_wtp(void)
{
/* Setup list of header fields */
static hf_register_info hf[] = {
{ &hf_wtp_header_sub_pdu_size,
{ "Sub PDU size", "wtp.sub_pdu_size",
FT_UINT16, BASE_DEC, NULL, 0x0,
"Size of Sub-PDU (bytes)", HFILL
}
},
{ &hf_wtp_header_flag_continue,
{ "Continue Flag", "wtp.continue_flag",
FT_BOOLEAN, 8, TFS( &continue_truth ), 0x80,
NULL, HFILL
}
},
{ &hf_wtp_header_pdu_type,
{ "PDU Type", "wtp.pdu_type",
FT_UINT8, BASE_HEX, VALS( vals_wtp_pdu_type ), 0x78,
NULL, HFILL
}
},
{ &hf_wtp_header_flag_Trailer,
{ "Trailer Flags", "wtp.trailer_flags",
FT_UINT8, BASE_HEX, VALS( vals_transaction_trailer ), 0x06,
NULL, HFILL
}
},
{ &hf_wtp_header_flag_RID,
{ "Re-transmission Indicator", "wtp.RID",
FT_BOOLEAN, 8, TFS( &RID_truth ), 0x01,
NULL, HFILL
}
},
{ &hf_wtp_header_flag_TID_response,
{ "TID Response", "wtp.TID.response",
FT_BOOLEAN, 16, TFS( &tid_response_truth ), 0x8000,
NULL, HFILL
}
},
{ &hf_wtp_header_flag_TID,
{ "Transaction ID", "wtp.TID",
FT_UINT16, BASE_HEX, NULL, 0x7FFF,
NULL, HFILL
}
},
{ &hf_wtp_header_Inv_version,
{ "Version", "wtp.header.version",
FT_UINT8, BASE_HEX, VALS( vals_version ), 0xC0,
NULL, HFILL
}
},
{ &hf_wtp_header_Inv_flag_TIDNew,
{ "TIDNew", "wtp.header.TIDNew",
FT_BOOLEAN, 8, TFS( &TIDNew_truth ), 0x20,
NULL, HFILL
}
},
{ &hf_wtp_header_Inv_flag_UP,
{ "U/P flag", "wtp.header.UP",
FT_BOOLEAN, 8, TFS( &UP_truth ), 0x10,
NULL, HFILL
}
},
{ &hf_wtp_header_Inv_Reserved,
{ "Reserved", "wtp.inv.reserved",
FT_UINT8, BASE_HEX, NULL, 0x0C,
NULL, HFILL
}
},
{ &hf_wtp_header_Inv_TransactionClass,
{ "Transaction Class", "wtp.inv.transaction_class",
FT_UINT8, BASE_HEX, VALS( vals_transaction_classes ), 0x03,
NULL, HFILL
}
},
{ &hf_wtp_header_Ack_flag_TVETOK,
{ "Tve/Tok flag", "wtp.ack.tvetok",
FT_BOOLEAN, 8, TFS( &TVETOK_truth ), 0x04,
NULL, HFILL
}
},
{ &hf_wtp_header_Abort_type,
{ "Abort Type", "wtp.abort.type",
FT_UINT8, BASE_HEX, VALS ( vals_abort_type ), 0x07,
NULL, HFILL
}
},
{ &hf_wtp_header_Abort_reason_provider,
{ "Abort Reason", "wtp.abort.reason.provider",
FT_UINT8, BASE_HEX, VALS ( vals_abort_reason_provider ), 0x00,
NULL, HFILL
}
},
/* Assume WSP is the user and use its reason codes */
{ &hf_wtp_header_Abort_reason_user,
{ "Abort Reason", "wtp.abort.reason.user",
FT_UINT8, BASE_HEX|BASE_EXT_STRING, &vals_wsp_reason_codes_ext, 0x00,
NULL, HFILL
}
},
{ &hf_wtp_header_sequence_number,
{ "Packet Sequence Number", "wtp.header.sequence",
FT_UINT8, BASE_DEC, NULL, 0x00,
NULL, HFILL
}
},
{ &hf_wtp_header_missing_packets,
{ "Missing Packets", "wtp.header.missing_packets",
FT_UINT8, BASE_DEC, NULL, 0x00,
NULL, HFILL
}
},
{ &hf_wtp_payload,
{ "Payload", "wtp.payload",
FT_BYTES, BASE_NONE, NULL, 0x00,
NULL, HFILL
}
},
#if 0
{ &hf_wtp_header_variable_part,
{ "Header: Variable part", "wtp.header_variable_part",
FT_BYTES, BASE_NONE, NULL, 0x0,
"Variable part of the header", HFILL
}
},
{ &hf_wtp_data,
{ "Data", "wtp.header_data",
FT_BYTES, BASE_NONE, NULL, 0x0,
NULL, HFILL
}
},
#endif
{ &hf_wtp_tpi_type,
{ "TPI", "wtp.tpi",
FT_UINT8, BASE_HEX, VALS(vals_tpi_type), 0x00,
"Identification of the Transport Information Item", HFILL
}
},
{ &hf_wtp_tpi_psn,
{ "Packet sequence number", "wtp.tpi.psn",
FT_UINT8, BASE_DEC, NULL, 0x00,
"Sequence number of this packet", HFILL
}
},
{ &hf_wtp_tpi_opt,
{ "Option", "wtp.tpi.opt",
FT_UINT8, BASE_HEX, VALS(vals_tpi_opt), 0x00,
"The given option for this TPI", HFILL
}
},
{ &hf_wtp_tpi_optval,
{ "Option Value", "wtp.tpi.opt.val",
FT_NONE, BASE_NONE, NULL, 0x00,
"The value that is supplied with this option", HFILL
}
},
{ &hf_wtp_tpi_info,
{ "Information", "wtp.tpi.info",
FT_NONE, BASE_NONE, NULL, 0x00,
"The information being send by this TPI", HFILL
}
},
/* Fragment fields */
{ &hf_wtp_fragment_overlap,
{ "Fragment overlap", "wtp.fragment.overlap",
FT_BOOLEAN, BASE_NONE, NULL, 0x0,
"Fragment overlaps with other fragments", HFILL
}
},
{ &hf_wtp_fragment_overlap_conflict,
{ "Conflicting data in fragment overlap", "wtp.fragment.overlap.conflict",
FT_BOOLEAN, BASE_NONE, NULL, 0x0,
"Overlapping fragments contained conflicting data", HFILL
}
},
{ &hf_wtp_fragment_multiple_tails,
{ "Multiple tail fragments found", "wtp.fragment.multipletails",
FT_BOOLEAN, BASE_NONE, NULL, 0x0,
"Several tails were found when defragmenting the packet", HFILL
}
},
{ &hf_wtp_fragment_too_long_fragment,
{ "Fragment too long", "wtp.fragment.toolongfragment",
FT_BOOLEAN, BASE_NONE, NULL, 0x0,
"Fragment contained data past end of packet", HFILL
}
},
{ &hf_wtp_fragment_error,
{ "Defragmentation error", "wtp.fragment.error",
FT_FRAMENUM, BASE_NONE, NULL, 0x0,
"Defragmentation error due to illegal fragments", HFILL
}
},
{ &hf_wtp_fragment_count,
{ "Fragment count", "wtp.fragment.count",
FT_UINT32, BASE_DEC, NULL, 0x0,
NULL, HFILL
}
},
{ &hf_wtp_reassembled_in,
{ "Reassembled in", "wtp.reassembled.in",
FT_FRAMENUM, BASE_NONE, NULL, 0x0,
"WTP fragments are reassembled in the given packet", HFILL
}
},
{ &hf_wtp_reassembled_length,
{ "Reassembled WTP length", "wtp.reassembled.length",
FT_UINT32, BASE_DEC, NULL, 0x0,
"The total length of the reassembled payload", HFILL
}
},
{ &hf_wtp_fragment,
{ "WTP Fragment", "wtp.fragment",
FT_FRAMENUM, BASE_NONE, NULL, 0x0,
NULL, HFILL
}
},
{ &hf_wtp_fragments,
{ "WTP Fragments", "wtp.fragments",
FT_NONE, BASE_NONE, NULL, 0x0,
NULL, HFILL
}
},
};
/* Setup protocol subtree array */
static gint *ett[] = {
&ett_wtp,
&ett_wtp_sub_pdu_tree,
&ett_header,
&ett_tpilist,
&ett_wsp_fragments,
&ett_wtp_fragment,
};
/* Register the protocol name and description */
proto_wtp = proto_register_protocol(
"Wireless Transaction Protocol", /* protocol name for use by wireshark */
"WTP", /* short version of name */
"wtp" /* Abbreviated protocol name, should Match IANA
< URL:http://www.iana.org/assignments/port-numbers/ >
*/
);
/* Required calls to register the header fields and subtrees used */
proto_register_field_array(proto_wtp, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
register_dissector("wtp-wtls", dissect_wtp_fromwtls, proto_wtp);
wtp_fromudp_handle = register_dissector("wtp-udp", dissect_wtp_fromudp, proto_wtp);
reassembly_table_register(&wtp_reassembly_table,
&addresses_reassembly_table_functions);
}
void
proto_reg_handoff_wtp(void)
{
/*
* Get a handle for the connection-oriented WSP dissector - if WTP
* PDUs have data, it is WSP.
*/
wsp_handle = find_dissector_add_dependency("wsp-co", proto_wtp);
dissector_add_uint_with_preference("udp.port", UDP_PORT_WTP_WSP, wtp_fromudp_handle);
dissector_add_uint("gsm_sms_ud.udh.port", UDP_PORT_WTP_WSP, wtp_fromudp_handle);
dissector_add_uint("gsm_sms.udh.port", UDP_PORT_WTP_WSP, wtp_fromudp_handle);
}
/*
* Editor modelines - https://www.wireshark.org/tools/modelines.html
*
* Local variables:
* c-basic-offset: 4
* tab-width: 8
* indent-tabs-mode: nil
* End:
*
* vi: set shiftwidth=4 tabstop=8 expandtab:
* :indentSize=4:tabSize=8:noTabs=true:
*/