/* packet-wtp.c * * Routines to dissect WTP component of WAP traffic. * * $Id: packet-wtp.c,v 1.62 2004/01/27 00:20:37 obiot Exp $ * * Ethereal - Network traffic analyzer * By Gerald Combs * Copyright 1998 Gerald Combs * * WAP dissector based on original work by Ben Fowler * Updated by Neil Hunter * WTLS support by Alexandre P. Ferreira (Splice IP) * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #ifdef HAVE_CONFIG_H # include "config.h" #endif #include #include #ifdef NEED_SNPRINTF_H # include "snprintf.h" #endif #include #include #include #include "reassemble.h" #include "packet-wap.h" #include "packet-wtp.h" #include "packet-wsp.h" 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 = HF_EMPTY; /* These fields used by fixed part of header */ static int hf_wtp_header_sub_pdu_size = HF_EMPTY; static int hf_wtp_header_flag_continue = HF_EMPTY; static int hf_wtp_header_pdu_type = HF_EMPTY; static int hf_wtp_header_flag_Trailer = HF_EMPTY; static int hf_wtp_header_flag_RID = HF_EMPTY; static int hf_wtp_header_flag_TID = HF_EMPTY; static int hf_wtp_header_flag_TID_response = HF_EMPTY; /* These fields used by Invoke packets */ static int hf_wtp_header_Inv_version = HF_EMPTY; static int hf_wtp_header_Inv_flag_TIDNew = HF_EMPTY; static int hf_wtp_header_Inv_flag_UP = HF_EMPTY; static int hf_wtp_header_Inv_Reserved = HF_EMPTY; static int hf_wtp_header_Inv_TransactionClass = HF_EMPTY; static int hf_wtp_header_variable_part = HF_EMPTY; static int hf_wtp_data = HF_EMPTY; static int hf_wtp_tpi_type = HF_EMPTY; static int hf_wtp_tpi_psn = HF_EMPTY; static int hf_wtp_tpi_opt = HF_EMPTY; static int hf_wtp_tpi_optval = HF_EMPTY; static int hf_wtp_tpi_info = HF_EMPTY; static int hf_wtp_header_Ack_flag_TVETOK = HF_EMPTY; static int hf_wtp_header_Abort_type = HF_EMPTY; static int hf_wtp_header_Abort_reason_provider = HF_EMPTY; static int hf_wtp_header_Abort_reason_user = HF_EMPTY; static int hf_wtp_header_sequence_number = HF_EMPTY; static int hf_wtp_header_missing_packets = HF_EMPTY; /* These fields used when reassembling WTP fragments */ static int hf_wtp_fragments = HF_EMPTY; static int hf_wtp_fragment = HF_EMPTY; static int hf_wtp_fragment_overlap = HF_EMPTY; static int hf_wtp_fragment_overlap_conflict = HF_EMPTY; static int hf_wtp_fragment_multiple_tails = HF_EMPTY; static int hf_wtp_fragment_too_long_fragment = HF_EMPTY; static int hf_wtp_fragment_error = HF_EMPTY; static int hf_wtp_reassembled_in = HF_EMPTY; /* Initialize the subtree pointers */ static gint ett_wtp = ETT_EMPTY; static gint ett_wtp_sub_pdu_tree = ETT_EMPTY; static gint ett_header = ETT_EMPTY; static gint ett_tpilist = ETT_EMPTY; static gint ett_wsp_fragments = ETT_EMPTY; static gint ett_wtp_fragment = ETT_EMPTY; 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_reassembled_in, "fragments" }; /* Handle for WSP dissector */ static dissector_handle_t wsp_handle; /* * reassembly of WSP */ static GHashTable *wtp_fragment_table = NULL; static void wtp_defragment_init(void) { fragment_table_init(&wtp_fragment_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_item *subTree = NULL; 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; subTree = proto_tree_add_uint(tree, hf_wtp_tpi_type, tvb, 0, tvb_length(tvb), tType); proto_item_add_subtree(subTree, 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, bo_little_endian); break; case 0x02: /* Option */ proto_tree_add_item(subTree, hf_wtp_tpi_opt, tvb, offset++, 1, bo_little_endian); proto_tree_add_item(subTree, hf_wtp_tpi_optval, tvb, offset, tLen - 1, bo_little_endian); break; case 0x03: /* PSN */ proto_tree_add_item(subTree, hf_wtp_tpi_psn, tvb, offset, 1, bo_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) { static GString *szInfo = NULL; int offCur = 0; /* current offset from start of WTP data */ 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 = ' '; 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; if (szInfo == NULL) szInfo = g_string_sized_new(32); 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, bo_little_endian); 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 && check_col(pinfo->cinfo, COL_INFO)) { col_append_str(pinfo->cinfo, COL_INFO, ", "); } /* Skip the length field for the WTP sub-tvb */ wtp_tvb = tvb_new_subset(tvb, offCur + c_fieldlen, c_pdulen, 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 printf("WTP packet %u: tree = %p, pdu = %s (%u) length: %u\n", pinfo->fd->num, tree, match_strval(pdut, vals_wtp_pdu_type), pdut, tvb_length(tvb)); #endif /* Develop the string to put in the Info column */ g_string_sprintf(szInfo, "WTP %s", val_to_str(pdut, vals_wtp_pdu_type, "Unknown PDU type 0x%x")); 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)); g_string_sprintfa(szInfo, " Class %d", clsTransaction); 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) g_string_sprintfa(szInfo, " (%u)", psn); 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) { g_string_append( szInfo, " R" ); }; /* 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, 0, bo_little_endian); #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, bo_little_endian); switch(pdut) { case INVOKE: proto_tree_add_item(wtp_tree, hf_wtp_header_flag_Trailer, tvb, offCur, 1, bo_little_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_flag_RID, tvb, offCur, 1, bo_little_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID_response, tvb, offCur + 1, 2, bo_big_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID, tvb, offCur + 1, 2, bo_big_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_Inv_version , tvb, offCur + 3, 1, bo_little_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_Inv_flag_TIDNew, tvb, offCur + 3, 1, bo_little_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_Inv_flag_UP, tvb, offCur + 3, 1, bo_little_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_Inv_Reserved, tvb, offCur + 3, 1, bo_little_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_Inv_TransactionClass, tvb, offCur + 3, 1, bo_little_endian); proto_item_append_text(ti, ", PDU: Invoke (%u)" ", Transaction Class: %s (%u)", INVOKE, match_strval(clsTransaction, vals_transaction_classes), clsTransaction); break; case RESULT: proto_tree_add_item(wtp_tree, hf_wtp_header_flag_Trailer, tvb, offCur, 1, bo_little_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_flag_RID, tvb, offCur, 1, bo_little_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID_response, tvb, offCur + 1, 2, bo_big_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID, tvb, offCur + 1, 2, bo_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, bo_big_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_flag_RID, tvb, offCur, 1, bo_little_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID_response, tvb, offCur + 1, 2, bo_big_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID, tvb, offCur + 1, 2, bo_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, bo_little_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID_response, tvb, offCur + 1, 2, bo_big_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID, tvb, offCur + 1, 2, bo_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, bo_little_endian); proto_item_append_text(ti, ", PDU: Abort (%u)" ", Type: Provider (%u)" ", Reason: %s (%u)", ABORT, PROVIDER, match_strval(reason, vals_abort_reason_provider), 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, bo_little_endian); proto_item_append_text(ti, ", PDU: Abort (%u)" ", Type: User (%u)" ", Reason: %s (%u)", ABORT, PROVIDER, match_strval(reason, vals_wsp_reason_codes), reason); } break; case SEGMENTED_INVOKE: proto_tree_add_item(wtp_tree, hf_wtp_header_flag_Trailer, tvb, offCur, 1, bo_little_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_flag_RID, tvb, offCur, 1, bo_little_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID_response, tvb, offCur + 1, 2, bo_big_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID, tvb, offCur + 1, 2, bo_big_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_sequence_number , tvb, offCur + 3, 1, bo_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, bo_little_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_flag_RID, tvb, offCur, 1, bo_little_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID_response, tvb, offCur + 1, 2, bo_big_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID, tvb, offCur + 1, 2, bo_big_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_sequence_number , tvb, offCur + 3, 1, bo_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, bo_little_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID_response, tvb, offCur + 1, 2, bo_big_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID, tvb, offCur + 1, 2, bo_big_endian); proto_tree_add_item(wtp_tree, hf_wtp_header_missing_packets , tvb, offCur + 3, 1, bo_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, bo_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 */ unsigned char tCon; unsigned char tByte; unsigned char 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(tvb, offCur + cbHeader + vHeader, tpiLen, 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_data *fd_wtp = NULL; guint32 reassembled_in = 0; gboolean save_fragmented = pinfo->fragmented; pinfo->fragmented = TRUE; fd_wtp = fragment_add_seq(tvb, dataOffset, pinfo, TID, wtp_fragment_table, psn, dataLen, !fTTR); /* XXX - fragment_add_seq() yields NULL unless Ethereal knows * that the packet is part of a reassembled whole. This means * that fd_wtp will be NULL as long as Ethereal did not encounter * (and process) the packet containing the last fragment. * This implies that Ethereal 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 printf("WTP: Packet %u %s -> %d: wsp_tvb = %p, fd_wtp = %p, frame = %u\n", pinfo->fd->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->fd->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 */ if (check_col(pinfo->cinfo, COL_INFO)) { col_append_fstr(pinfo->cinfo, COL_INFO, "%s (WTP payload reassembled in packet %u)", szInfo->str, fd_wtp->reassembled_in); } if (tree) { proto_tree_add_text(wtp_tree, tvb, dataOffset, -1, "Payload"); } } } else { /* Not reassembled yet, or not reassembled at all */ if (check_col(pinfo->cinfo, COL_INFO)) { col_append_fstr(pinfo->cinfo, COL_INFO, "%s (Unreassembled fragment %u)", szInfo->str, psn); } if (tree) { proto_tree_add_text(wtp_tree, tvb, dataOffset, -1, "Payload"); } } /* 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(tvb, dataOffset, -1, -1); /* We can safely hand the tvb to the WSP dissector */ call_dissector(wsp_handle, wsp_tvb, pinfo, tree); } else { /* Nothing to hand to subdissector */ if (check_col(pinfo->cinfo, COL_INFO)) col_append_str(pinfo->cinfo, COL_INFO, szInfo->str); } } else { /* Nothing to hand to subdissector */ if (check_col(pinfo->cinfo, COL_INFO)) col_append_str(pinfo->cinfo, COL_INFO, szInfo->str); } } /* * Called directly from UDP. * Put "WTP+WSP" into the "Protocol" column. */ static void dissect_wtp_fromudp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { if (check_col(pinfo->cinfo, COL_PROTOCOL)) col_set_str(pinfo->cinfo, COL_PROTOCOL, "WTP+WSP" ); if (check_col(pinfo->cinfo, COL_INFO)) col_clear(pinfo->cinfo, COL_INFO); dissect_wtp_common(tvb, pinfo, tree); } /* * 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 void dissect_wtp_fromwtls(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { if (check_col(pinfo->cinfo, COL_PROTOCOL)) col_set_str(pinfo->cinfo, COL_PROTOCOL, "WTLS+WTP+WSP" ); if (check_col(pinfo->cinfo, COL_INFO)) col_clear(pinfo->cinfo, COL_INFO); dissect_wtp_common(tvb, pinfo, tree); } /* Register the protocol with Ethereal */ 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, "Continue Flag", HFILL } }, { &hf_wtp_header_pdu_type, { "PDU Type", "wtp.pdu_type", FT_UINT8, BASE_HEX, VALS( vals_wtp_pdu_type ), 0x78, "PDU Type", HFILL } }, { &hf_wtp_header_flag_Trailer, { "Trailer Flags", "wtp.trailer_flags", FT_UINT8, BASE_HEX, VALS( vals_transaction_trailer ), 0x06, "Trailer Flags", HFILL } }, { &hf_wtp_header_flag_RID, { "Re-transmission Indicator", "wtp.RID", FT_BOOLEAN, 8, TFS( &RID_truth ), 0x01, "Re-transmission Indicator", HFILL } }, { &hf_wtp_header_flag_TID_response, { "TID Response", "wtp.TID.response", FT_BOOLEAN, 16, TFS( &tid_response_truth ), 0x8000, "TID Response", HFILL } }, { &hf_wtp_header_flag_TID, { "Transaction ID", "wtp.TID", FT_UINT16, BASE_HEX, NULL, 0x7FFF, "Transaction ID", HFILL } }, { &hf_wtp_header_Inv_version, { "Version", "wtp.header.version", FT_UINT8, BASE_HEX, VALS( vals_version ), 0xC0, "Version", HFILL } }, { &hf_wtp_header_Inv_flag_TIDNew, { "TIDNew", "wtp.header.TIDNew", FT_BOOLEAN, 8, TFS( &TIDNew_truth ), 0x20, "TIDNew", HFILL } }, { &hf_wtp_header_Inv_flag_UP, { "U/P flag", "wtp.header.UP", FT_BOOLEAN, 8, TFS( &UP_truth ), 0x10, "U/P Flag", HFILL } }, { &hf_wtp_header_Inv_Reserved, { "Reserved", "wtp.inv.reserved", FT_UINT8, BASE_HEX, NULL, 0x0C, "Reserved", HFILL } }, { &hf_wtp_header_Inv_TransactionClass, { "Transaction Class", "wtp.inv.transaction_class", FT_UINT8, BASE_HEX, VALS( vals_transaction_classes ), 0x03, "Transaction Class", HFILL } }, { &hf_wtp_header_Ack_flag_TVETOK, { "Tve/Tok flag", "wtp.ack.tvetok", FT_BOOLEAN, 8, TFS( &TVETOK_truth ), 0x04, "Tve/Tok flag", HFILL } }, { &hf_wtp_header_Abort_type, { "Abort Type", "wtp.abort.type", FT_UINT8, BASE_HEX, VALS ( vals_abort_type ), 0x07, "Abort Type", HFILL } }, { &hf_wtp_header_Abort_reason_provider, { "Abort Reason", "wtp.abort.reason.provider", FT_UINT8, BASE_HEX, VALS ( vals_abort_reason_provider ), 0x00, "Abort Reason", 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, VALS ( vals_wsp_reason_codes ), 0x00, "Abort Reason", HFILL } }, { &hf_wtp_header_sequence_number, { "Packet Sequence Number", "wtp.header.sequence", FT_UINT8, BASE_DEC, NULL, 0x00, "Packet Sequence Number", HFILL } }, { &hf_wtp_header_missing_packets, { "Missing Packets", "wtp.header.missing_packets", FT_UINT8, BASE_DEC, NULL, 0x00, "Missing Packets", HFILL } }, { &hf_wtp_header_variable_part, { "Header: Variable part", "wtp.header_variable_part", FT_BYTES, BASE_HEX, NULL, 0x0, "Variable part of the header", HFILL } }, { &hf_wtp_data, { "Data", "wtp.header_data", FT_BYTES, BASE_HEX, NULL, 0x0, "Data", HFILL } }, { &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_reassembled_in, { "Reassembled in", "wtp.reassembled.in", FT_FRAMENUM, BASE_NONE, NULL, 0x0, "WTP fragments are reassembled in the given packet", HFILL } }, { &hf_wtp_fragment, { "WTP Fragment", "wtp.fragment", FT_FRAMENUM, BASE_NONE, NULL, 0x0, "WTP Fragment", HFILL } }, { &hf_wtp_fragments, { "WTP Fragments", "wtp.fragments", FT_NONE, BASE_NONE, NULL, 0x0, "WTP Fragments", 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 ethereal */ "WTP", /* short version of name */ "wtp" /* Abbreviated protocol name, should Match IANA < URL:http://www.isi.edu/in-notes/iana/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); register_dissector("wtp-udp", dissect_wtp_fromudp, proto_wtp); register_init_routine(wtp_defragment_init); } void proto_reg_handoff_wtp(void) { dissector_handle_t wtp_fromudp_handle; /* * Get a handle for the connection-oriented WSP dissector - if WTP * PDUs have data, it is WSP. */ wsp_handle = find_dissector("wsp-co"); wtp_fromudp_handle = find_dissector("wtp-udp"); dissector_add("udp.port", UDP_PORT_WTP_WSP, wtp_fromudp_handle); dissector_add("gsm-sms-ud.udh.port", UDP_PORT_WTP_WSP, wtp_fromudp_handle); }