forked from osmocom/wireshark
![Michael Mann](/assets/img/avatar_default.png)
This saves many dissectors the need to find the data dissector and store a handle to it. There were also some that were finding it, but not using it. For others this was the only reason for their handoff function, so it could be eliminated. Change-Id: I5d3f951ee1daa3d30c060d21bd12bbc881a8027b Reviewed-on: https://code.wireshark.org/review/14530 Petri-Dish: Michael Mann <mmann78@netscape.net> Reviewed-by: Michael Mann <mmann78@netscape.net>
728 lines
24 KiB
C
728 lines
24 KiB
C
/* packet-tftp.c
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* Routines for tftp packet dissection
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*
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* Richard Sharpe <rsharpe@ns.aus.com>
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* Craig Newell <CraigN@cheque.uq.edu.au>
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* RFC2347 TFTP Option Extension
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* Joerg Mayer (see AUTHORS file)
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* RFC2348 TFTP Blocksize Option
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*
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* Wireshark - Network traffic analyzer
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* By Gerald Combs <gerald@wireshark.org>
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* Copyright 1998 Gerald Combs
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*
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* Copied from packet-bootp.c
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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*/
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/* Documentation:
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* RFC 1350: THE TFTP PROTOCOL (REVISION 2)
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* RFC 2090: TFTP Multicast Option
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* (not yet implemented)
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* RFC 2347: TFTP Option Extension
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* RFC 2348: TFTP Blocksize Option
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* RFC 2349: TFTP Timeout Interval and Transfer Size Options
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* (not yet implemented)
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*/
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#include "config.h"
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#include <stdlib.h>
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#include <epan/packet.h>
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#include <epan/conversation.h>
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#include <epan/expert.h>
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#include <epan/prefs.h>
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#include <epan/tap.h>
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#include "packet-tftp.h"
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void proto_register_tftp(void);
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/* Things we may want to remember for a whole conversation */
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typedef struct _tftp_conv_info_t {
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guint16 blocksize;
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gchar *source_file, *destination_file;
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/* Sequence analysis */
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guint next_block_num;
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gboolean blocks_missing;
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/* When exporting file object, build up list of data blocks here */
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guint next_tap_block_num;
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GSList *block_list;
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guint file_length;
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} tftp_conv_info_t;
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static int proto_tftp = -1;
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static int hf_tftp_opcode = -1;
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static int hf_tftp_source_file = -1;
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static int hf_tftp_destination_file = -1;
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static int hf_tftp_transfer_type = -1;
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static int hf_tftp_blocknum = -1;
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static int hf_tftp_error_code = -1;
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static int hf_tftp_error_string = -1;
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static int hf_tftp_option_name = -1;
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static int hf_tftp_option_value = -1;
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static int hf_tftp_data = -1;
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static gint ett_tftp = -1;
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static gint ett_tftp_option = -1;
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static expert_field ei_tftp_blocksize_range = EI_INIT;
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static dissector_handle_t tftp_handle;
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#define UDP_PORT_TFTP_RANGE "69"
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void proto_reg_handoff_tftp (void);
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/* User definable values */
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static range_t *global_tftp_port_range;
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/* minimum length is an ACK message of 4 bytes */
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#define MIN_HDR_LEN 4
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#define TFTP_RRQ 1
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#define TFTP_WRQ 2
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#define TFTP_DATA 3
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#define TFTP_ACK 4
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#define TFTP_ERROR 5
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#define TFTP_OACK 6
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#define TFTP_INFO 255
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static const value_string tftp_opcode_vals[] = {
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{ TFTP_RRQ, "Read Request" },
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{ TFTP_WRQ, "Write Request" },
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{ TFTP_DATA, "Data Packet" },
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{ TFTP_ACK, "Acknowledgement" },
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{ TFTP_ERROR, "Error Code" },
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{ TFTP_OACK, "Option Acknowledgement" },
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{ TFTP_INFO, "Information (MSDP)" },
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{ 0, NULL }
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};
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#define TFTP_ERR_NOT_DEF 0
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#define TFTP_ERR_NOT_FOUND 1
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#define TFTP_ERR_NOT_ALLOWED 2
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#define TFTP_ERR_DISK_FULL 3
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#define TFTP_ERR_BAD_OP 4
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#define TFTP_ERR_BAD_ID 5
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#define TFTP_ERR_EXISTS 6
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#define TFTP_ERR_NO_USER 7
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#define TFTP_ERR_OPT_FAIL 8
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static const value_string tftp_error_code_vals[] = {
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{ TFTP_ERR_NOT_DEF, "Not defined" },
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{ TFTP_ERR_NOT_FOUND, "File not found" },
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{ TFTP_ERR_NOT_ALLOWED, "Access violation" },
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{ TFTP_ERR_DISK_FULL, "Disk full or allocation exceeded" },
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{ TFTP_ERR_BAD_OP, "Illegal TFTP Operation" },
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{ TFTP_ERR_BAD_ID, "Unknown transfer ID" }, /* Does not cause termination */
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{ TFTP_ERR_EXISTS, "File already exists" },
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{ TFTP_ERR_NO_USER, "No such user" },
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{ TFTP_ERR_OPT_FAIL, "Option negotiation failed" },
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{ 0, NULL }
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};
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static int tftp_eo_tap = -1;
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static void
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tftp_dissect_options(tvbuff_t *tvb, packet_info *pinfo, int offset,
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proto_tree *tree, guint16 opcode, tftp_conv_info_t *tftp_info)
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{
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int option_len, value_len;
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int value_offset;
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const char *optionname;
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const char *optionvalue;
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proto_tree *opt_tree;
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while (tvb_offset_exists(tvb, offset)) {
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/* option_len and value_len include the trailing 0 byte */
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option_len = tvb_strsize(tvb, offset);
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value_offset = offset + option_len;
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value_len = tvb_strsize(tvb, value_offset);
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/* use xxx_len-1 to exclude the trailing 0 byte, it would be
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displayed as nonprinting character
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tvb_format_text() creates a temporary 0-terminated buffer */
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optionname = tvb_format_text(tvb, offset, option_len-1);
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optionvalue = tvb_format_text(tvb, value_offset, value_len-1);
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opt_tree = proto_tree_add_subtree_format(tree, tvb, offset, option_len+value_len,
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ett_tftp_option, NULL, "Option: %s = %s", optionname, optionvalue);
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proto_tree_add_item(opt_tree, hf_tftp_option_name, tvb, offset,
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option_len, ENC_ASCII|ENC_NA);
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proto_tree_add_item(opt_tree, hf_tftp_option_value, tvb, value_offset,
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value_len, ENC_ASCII|ENC_NA);
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offset += option_len + value_len;
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col_append_fstr(pinfo->cinfo, COL_INFO, ", %s=%s",
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optionname, optionvalue);
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/* Special code to handle individual options */
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if (!g_ascii_strcasecmp((const char *)optionname, "blksize") &&
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opcode == TFTP_OACK) {
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gint blocksize = (gint)strtol((const char *)optionvalue, NULL, 10);
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if (blocksize < 8 || blocksize > 65464) {
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expert_add_info(pinfo, NULL, &ei_tftp_blocksize_range);
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} else {
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tftp_info->blocksize = blocksize;
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}
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}
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}
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}
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static void cleanup_tftp_blocks(tftp_conv_info_t *conv)
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{
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GSList *block_iterator;
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/* Walk list of block items */
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for (block_iterator = conv->block_list; block_iterator; block_iterator = block_iterator->next) {
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file_block_t *block = (file_block_t*)block_iterator->data;
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/* Free block data */
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wmem_free(NULL, block->data);
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/* Free block itself */
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g_free(block);
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}
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conv->block_list = NULL;
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conv->file_length = 0;
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}
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static void dissect_tftp_message(tftp_conv_info_t *tftp_info,
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tvbuff_t *tvb, packet_info *pinfo,
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proto_tree *tree)
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{
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proto_tree *tftp_tree;
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proto_item *ti;
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gint offset = 0;
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guint16 opcode;
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guint16 bytes;
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guint16 blocknum;
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guint i1;
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guint16 error;
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tvbuff_t *data_tvb = NULL;
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col_set_str(pinfo->cinfo, COL_PROTOCOL, "TFTP");
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/* Protocol root */
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ti = proto_tree_add_item(tree, proto_tftp, tvb, offset, -1, ENC_NA);
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tftp_tree = proto_item_add_subtree(ti, ett_tftp);
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/* Opcode */
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opcode = tvb_get_ntohs(tvb, offset);
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proto_tree_add_uint(tftp_tree, hf_tftp_opcode, tvb, offset, 2, opcode);
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col_add_str(pinfo->cinfo, COL_INFO,
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val_to_str(opcode, tftp_opcode_vals, "Unknown (0x%04x)"));
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offset += 2;
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/* read and write requests contain file names
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for other messages, we add the filenames from the conversation */
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if (opcode!=TFTP_RRQ && opcode!=TFTP_WRQ) {
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if (tftp_info->source_file) {
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ti = proto_tree_add_string(tftp_tree, hf_tftp_source_file, tvb,
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0, 0, tftp_info->source_file);
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PROTO_ITEM_SET_GENERATED(ti);
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}
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if (tftp_info->destination_file) {
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ti = proto_tree_add_string(tftp_tree, hf_tftp_destination_file, tvb,
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0, 0, tftp_info->destination_file);
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PROTO_ITEM_SET_GENERATED(ti);
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}
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}
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switch (opcode) {
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case TFTP_RRQ:
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i1 = tvb_strsize(tvb, offset);
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proto_tree_add_item(tftp_tree, hf_tftp_source_file,
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tvb, offset, i1, ENC_ASCII|ENC_NA);
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tftp_info->source_file = tvb_get_string_enc(wmem_file_scope(), tvb, offset, i1, ENC_ASCII);
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/* we either have a source file name (for read requests) or a
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destination file name (for write requests)
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when we set one of the names, we clear the other */
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tftp_info->destination_file = NULL;
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col_append_fstr(pinfo->cinfo, COL_INFO, ", File: %s",
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tvb_format_stringzpad(tvb, offset, i1));
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offset += i1;
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i1 = tvb_strsize(tvb, offset);
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proto_tree_add_item(tftp_tree, hf_tftp_transfer_type,
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tvb, offset, i1, ENC_ASCII|ENC_NA);
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col_append_fstr(pinfo->cinfo, COL_INFO, ", Transfer type: %s",
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tvb_format_stringzpad(tvb, offset, i1));
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offset += i1;
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tftp_dissect_options(tvb, pinfo, offset, tftp_tree,
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opcode, tftp_info);
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break;
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case TFTP_WRQ:
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i1 = tvb_strsize(tvb, offset);
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proto_tree_add_item(tftp_tree, hf_tftp_destination_file,
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tvb, offset, i1, ENC_ASCII|ENC_NA);
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tftp_info->destination_file =
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tvb_get_string_enc(wmem_file_scope(), tvb, offset, i1, ENC_ASCII);
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tftp_info->source_file = NULL; /* see above */
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col_append_fstr(pinfo->cinfo, COL_INFO, ", File: %s",
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tvb_format_stringzpad(tvb, offset, i1));
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offset += i1;
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i1 = tvb_strsize(tvb, offset);
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proto_tree_add_item(tftp_tree, hf_tftp_transfer_type,
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tvb, offset, i1, ENC_ASCII|ENC_NA);
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col_append_fstr(pinfo->cinfo, COL_INFO, ", Transfer type: %s",
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tvb_format_stringzpad(tvb, offset, i1));
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offset += i1;
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tftp_dissect_options(tvb, pinfo, offset, tftp_tree,
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opcode, tftp_info);
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break;
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case TFTP_INFO:
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tftp_dissect_options(tvb, pinfo, offset, tftp_tree,
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opcode, tftp_info);
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break;
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case TFTP_DATA:
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blocknum = tvb_get_ntohs(tvb, offset);
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proto_tree_add_uint(tftp_tree, hf_tftp_blocknum, tvb, offset, 2,
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blocknum);
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/* Sequence analysis on blocknums (first pass only) */
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if (!pinfo->fd->flags.visited) {
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if (blocknum > tftp_info->next_block_num) {
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/* There is a gap. Don't try to recover from this. */
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tftp_info->next_block_num = blocknum + 1;
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tftp_info->blocks_missing = TRUE;
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/* TODO: add info to a result table for showing expert info in later passes */
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}
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else if (blocknum == tftp_info->next_block_num) {
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/* OK, inc what we expect next */
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tftp_info->next_block_num++;
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}
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}
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offset += 2;
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/* Show number of bytes in this block, and whether it is the end of the file */
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bytes = tvb_reported_length_remaining(tvb, offset);
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col_append_fstr(pinfo->cinfo, COL_INFO, ", Block: %i%s",
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blocknum,
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(bytes < tftp_info->blocksize)?" (last)":"" );
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/* Show data in tree */
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if (bytes > 0) {
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data_tvb = tvb_new_subset(tvb, offset, -1, bytes);
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call_data_dissector(data_tvb, pinfo, tree);
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}
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/* If Export Object tap is listening, need to accumulate blocks info list
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to send to tap. But if already know there are blocks missing, there is no
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point in trying. */
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if (have_tap_listener(tftp_eo_tap) && !tftp_info->blocks_missing) {
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file_block_t *block;
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if (blocknum == 1) {
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/* Reset data for this conversation, freeing any accumulated blocks! */
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cleanup_tftp_blocks(tftp_info);
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tftp_info->next_tap_block_num = 1;
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}
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if (blocknum != tftp_info->next_tap_block_num) {
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/* Ignore. Could be missing frames, or just clicking previous frame */
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return;
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}
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if (bytes > 0) {
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/* Create a block for this block */
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block = (file_block_t*)g_malloc(sizeof(file_block_t));
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block->length = bytes;
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block->data = tvb_memdup(NULL, data_tvb, 0, bytes);
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/* Add to the end of the list (does involve traversing whole list..) */
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tftp_info->block_list = g_slist_append(tftp_info->block_list, block);
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tftp_info->file_length += bytes;
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/* Look for next blocknum next time */
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tftp_info->next_tap_block_num++;
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}
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/* Tap export object only when reach end of file */
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if (bytes < tftp_info->blocksize) {
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tftp_eo_t *eo_info;
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/* If don't have a filename, won't tap file info */
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if ((tftp_info->source_file == NULL) && (tftp_info->destination_file == NULL)) {
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cleanup_tftp_blocks(tftp_info);
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return;
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}
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/* Create the eo_info to pass to the listener */
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eo_info = wmem_new(wmem_packet_scope(), tftp_eo_t);
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/* Set filename */
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if (tftp_info->source_file) {
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eo_info->filename = g_strdup(tftp_info->source_file);
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}
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else if (tftp_info->destination_file) {
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eo_info->filename = g_strdup(tftp_info->destination_file);
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}
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/* Send block list, which will be combined and freed at tap. */
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eo_info->payload_len = tftp_info->file_length;
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eo_info->pkt_num = blocknum;
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eo_info->block_list = tftp_info->block_list;
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/* Send to tap */
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tap_queue_packet(tftp_eo_tap, pinfo, eo_info);
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/* Have sent, so forget list of blocks, and only pay attention if we
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get back to the first block again. */
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tftp_info->block_list = NULL;
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tftp_info->next_tap_block_num = 1;
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}
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}
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break;
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case TFTP_ACK:
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blocknum = tvb_get_ntohs(tvb, offset);
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proto_tree_add_uint(tftp_tree, hf_tftp_blocknum, tvb, offset, 2,
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blocknum);
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col_append_fstr(pinfo->cinfo, COL_INFO, ", Block: %i",
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blocknum);
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break;
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case TFTP_ERROR:
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error = tvb_get_ntohs(tvb, offset);
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proto_tree_add_uint(tftp_tree, hf_tftp_error_code, tvb, offset, 2,
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error);
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col_append_fstr(pinfo->cinfo, COL_INFO, ", Code: %s",
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val_to_str(error, tftp_error_code_vals, "Unknown (%u)"));
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offset += 2;
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i1 = tvb_strsize(tvb, offset);
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proto_tree_add_item(tftp_tree, hf_tftp_error_string, tvb, offset,
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i1, ENC_ASCII|ENC_NA);
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col_append_fstr(pinfo->cinfo, COL_INFO, ", Message: %s",
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tvb_format_stringzpad(tvb, offset, i1));
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expert_add_info(pinfo, NULL, &ei_tftp_blocksize_range);
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break;
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case TFTP_OACK:
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tftp_dissect_options(tvb, pinfo, offset, tftp_tree,
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opcode, tftp_info);
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break;
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default:
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proto_tree_add_item(tftp_tree, hf_tftp_data, tvb, offset, -1, ENC_NA);
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break;
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}
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}
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static gboolean
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dissect_embeddedtftp_heur(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
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{
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/* Used to dissect TFTP packets where one can not assume
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that the TFTP is the only protocol used by that port, and
|
|
that TFTP may not be carried by UDP */
|
|
conversation_t *conversation = NULL;
|
|
guint16 opcode;
|
|
tftp_conv_info_t *tftp_info;
|
|
|
|
/*
|
|
* We need to verify it could be a TFTP message before creating a conversation
|
|
*/
|
|
|
|
if (tvb_captured_length(tvb) < MIN_HDR_LEN)
|
|
return FALSE;
|
|
|
|
opcode = tvb_get_ntohs(tvb, 0);
|
|
|
|
switch (opcode) {
|
|
case TFTP_RRQ:
|
|
case TFTP_WRQ:
|
|
/* These 2 opcodes have a NULL-terminated source file name after opcode. Verify */
|
|
{
|
|
gint char_offset = 1;
|
|
while (tvb_captured_length_remaining(tvb, char_offset)) {
|
|
gchar c = (gchar)tvb_get_guint8(tvb, char_offset++);
|
|
if (c == '\0') {
|
|
/* NULL termination found - continue with dissection */
|
|
break;
|
|
}
|
|
else if (!g_ascii_isprint(c)) {
|
|
/* Not part of a file name - give up now */
|
|
return FALSE;
|
|
}
|
|
}
|
|
/* Would have to have a short capture length to not include the whole filename,
|
|
but fall through here anyway rather than returning FALSE */
|
|
}
|
|
/* Intentionally dropping through here... */
|
|
case TFTP_DATA:
|
|
case TFTP_ACK:
|
|
case TFTP_OACK:
|
|
case TFTP_INFO:
|
|
break;
|
|
case TFTP_ERROR:
|
|
/* for an error, we can verify the error code is legit */
|
|
switch (tvb_get_ntohs(tvb, 2)) {
|
|
case TFTP_ERR_NOT_DEF:
|
|
case TFTP_ERR_NOT_FOUND:
|
|
case TFTP_ERR_NOT_ALLOWED:
|
|
case TFTP_ERR_DISK_FULL:
|
|
case TFTP_ERR_BAD_OP:
|
|
case TFTP_ERR_BAD_ID:
|
|
case TFTP_ERR_EXISTS:
|
|
case TFTP_ERR_NO_USER:
|
|
case TFTP_ERR_OPT_FAIL:
|
|
break;
|
|
default:
|
|
return FALSE;
|
|
}
|
|
break;
|
|
default:
|
|
return FALSE;
|
|
}
|
|
|
|
conversation = find_or_create_conversation(pinfo);
|
|
|
|
tftp_info = (tftp_conv_info_t *)conversation_get_proto_data(conversation, proto_tftp);
|
|
if (!tftp_info) {
|
|
tftp_info = wmem_new(wmem_file_scope(), tftp_conv_info_t);
|
|
tftp_info->blocksize = 512; /* TFTP default block size */
|
|
tftp_info->source_file = NULL;
|
|
tftp_info->destination_file = NULL;
|
|
tftp_info->next_block_num = 1;
|
|
tftp_info->blocks_missing = FALSE;
|
|
tftp_info->next_tap_block_num = 1;
|
|
tftp_info->block_list = NULL;
|
|
tftp_info->file_length = 0;
|
|
|
|
conversation_add_proto_data(conversation, proto_tftp, tftp_info);
|
|
}
|
|
|
|
dissect_tftp_message(tftp_info, tvb, pinfo, tree);
|
|
return TRUE;
|
|
}
|
|
|
|
static int
|
|
dissect_tftp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
|
|
{
|
|
conversation_t *conversation = NULL;
|
|
tftp_conv_info_t *tftp_info;
|
|
|
|
/*
|
|
* The first TFTP packet goes to the TFTP port; the second one
|
|
* comes from some *other* port, but goes back to the same
|
|
* IP address and port as the ones from which the first packet
|
|
* came; all subsequent packets go between those two IP addresses
|
|
* and ports.
|
|
*
|
|
* If this packet went to the TFTP port (either to one of the ports
|
|
* set in the preferences or to a port set via Decode As), we check
|
|
* to see if there's already a conversation with one address/port pair
|
|
* matching the source IP address and port of this packet,
|
|
* the other address matching the destination IP address of this
|
|
* packet, and any destination port.
|
|
*
|
|
* If not, we create one, with its address 1/port 1 pair being
|
|
* the source address/port of this packet, its address 2 being
|
|
* the destination address of this packet, and its port 2 being
|
|
* wildcarded, and give it the TFTP dissector as a dissector.
|
|
*/
|
|
if (value_is_in_range(global_tftp_port_range, pinfo->destport) ||
|
|
(pinfo->match_uint == pinfo->destport)) {
|
|
conversation = find_conversation(pinfo->num, &pinfo->src, &pinfo->dst, PT_UDP,
|
|
pinfo->srcport, 0, NO_PORT_B);
|
|
if( (conversation == NULL) || (conversation_get_dissector(conversation, pinfo->num) != tftp_handle) ){
|
|
conversation = conversation_new(pinfo->num, &pinfo->src, &pinfo->dst, PT_UDP,
|
|
pinfo->srcport, 0, NO_PORT2);
|
|
conversation_set_dissector(conversation, tftp_handle);
|
|
}
|
|
} else {
|
|
conversation = find_conversation(pinfo->num, &pinfo->src, &pinfo->dst,
|
|
pinfo->ptype, pinfo->srcport, pinfo->destport, 0);
|
|
if( (conversation == NULL) || (conversation_get_dissector(conversation, pinfo->num) != tftp_handle) ){
|
|
conversation = conversation_new(pinfo->num, &pinfo->src, &pinfo->dst, PT_UDP,
|
|
pinfo->destport, pinfo->srcport, 0);
|
|
conversation_set_dissector(conversation, tftp_handle);
|
|
} else if (conversation->options & NO_PORT_B) {
|
|
if (pinfo->destport == conversation->key_ptr->port1)
|
|
conversation_set_port2(conversation, pinfo->srcport);
|
|
else
|
|
return 0;
|
|
}
|
|
}
|
|
tftp_info = (tftp_conv_info_t *)conversation_get_proto_data(conversation, proto_tftp);
|
|
if (!tftp_info) {
|
|
tftp_info = wmem_new(wmem_file_scope(), tftp_conv_info_t);
|
|
tftp_info->blocksize = 512; /* TFTP default block size */
|
|
tftp_info->source_file = NULL;
|
|
tftp_info->destination_file = NULL;
|
|
tftp_info->next_block_num = 1;
|
|
tftp_info->blocks_missing = FALSE;
|
|
tftp_info->next_tap_block_num = 1;
|
|
tftp_info->block_list = NULL;
|
|
tftp_info->file_length = 0;
|
|
conversation_add_proto_data(conversation, proto_tftp, tftp_info);
|
|
}
|
|
|
|
dissect_tftp_message(tftp_info, tvb, pinfo, tree);
|
|
return tvb_captured_length(tvb);
|
|
}
|
|
|
|
|
|
void
|
|
proto_register_tftp(void)
|
|
{
|
|
static hf_register_info hf[] = {
|
|
{ &hf_tftp_opcode,
|
|
{ "Opcode", "tftp.opcode",
|
|
FT_UINT16, BASE_DEC, VALS(tftp_opcode_vals), 0x0,
|
|
"TFTP message type", HFILL }},
|
|
|
|
{ &hf_tftp_source_file,
|
|
{ "Source File", "tftp.source_file",
|
|
FT_STRINGZ, BASE_NONE, NULL, 0x0,
|
|
"TFTP source file name", HFILL }},
|
|
|
|
{ &hf_tftp_destination_file,
|
|
{ "DESTINATION File", "tftp.destination_file",
|
|
FT_STRINGZ, BASE_NONE, NULL, 0x0,
|
|
"TFTP source file name", HFILL }},
|
|
|
|
{ &hf_tftp_transfer_type,
|
|
{ "Type", "tftp.type",
|
|
FT_STRINGZ, BASE_NONE, NULL, 0x0,
|
|
"TFTP transfer type", HFILL }},
|
|
|
|
{ &hf_tftp_blocknum,
|
|
{ "Block", "tftp.block",
|
|
FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
"Block number", HFILL }},
|
|
|
|
{ &hf_tftp_error_code,
|
|
{ "Error code", "tftp.error.code",
|
|
FT_UINT16, BASE_DEC, VALS(tftp_error_code_vals), 0x0,
|
|
"Error code in case of TFTP error message", HFILL }},
|
|
|
|
{ &hf_tftp_error_string,
|
|
{ "Error message", "tftp.error.message",
|
|
FT_STRINGZ, BASE_NONE, NULL, 0x0,
|
|
"Error string in case of TFTP error message", HFILL }},
|
|
|
|
{ &hf_tftp_option_name,
|
|
{ "Option name", "tftp.option.name",
|
|
FT_STRINGZ, BASE_NONE, NULL, 0x0,
|
|
NULL, HFILL }},
|
|
|
|
{ &hf_tftp_option_value,
|
|
{ "Option value", "tftp.option.value",
|
|
FT_STRINGZ, BASE_NONE, NULL, 0x0,
|
|
NULL, HFILL }},
|
|
|
|
{ &hf_tftp_data,
|
|
{ "Data", "tftp.data",
|
|
FT_BYTES, BASE_NONE, NULL, 0x0,
|
|
NULL, HFILL }},
|
|
};
|
|
static gint *ett[] = {
|
|
&ett_tftp,
|
|
&ett_tftp_option,
|
|
};
|
|
|
|
static ei_register_info ei[] = {
|
|
{ &ei_tftp_blocksize_range, { "tftp.blocksize_range", PI_RESPONSE_CODE, PI_WARN, "TFTP blocksize out of range", EXPFILL }},
|
|
};
|
|
|
|
module_t *tftp_module;
|
|
expert_module_t* expert_tftp;
|
|
|
|
proto_tftp = proto_register_protocol("Trivial File Transfer Protocol",
|
|
"TFTP", "tftp");
|
|
proto_register_field_array(proto_tftp, hf, array_length(hf));
|
|
proto_register_subtree_array(ett, array_length(ett));
|
|
expert_tftp = expert_register_protocol(proto_tftp);
|
|
expert_register_field_array(expert_tftp, ei, array_length(ei));
|
|
|
|
register_dissector("tftp", dissect_tftp, proto_tftp);
|
|
|
|
/* Set default UDP ports */
|
|
range_convert_str(&global_tftp_port_range, UDP_PORT_TFTP_RANGE, MAX_UDP_PORT);
|
|
|
|
tftp_module = prefs_register_protocol(proto_tftp, proto_reg_handoff_tftp);
|
|
prefs_register_range_preference(tftp_module, "udp_ports",
|
|
"TFTP port numbers",
|
|
"Port numbers used for TFTP traffic "
|
|
"(default " UDP_PORT_TFTP_RANGE ")",
|
|
&global_tftp_port_range, MAX_UDP_PORT);
|
|
|
|
/* Register the tap for the "Export Object" function */
|
|
tftp_eo_tap = register_tap("tftp_eo"); /* TFTP Export Object tap */
|
|
}
|
|
|
|
void
|
|
proto_reg_handoff_tftp(void)
|
|
{
|
|
static range_t *tftp_port_range;
|
|
static gboolean tftp_initialized = FALSE;
|
|
|
|
if (!tftp_initialized) {
|
|
tftp_handle = find_dissector("tftp");
|
|
heur_dissector_add("stun", dissect_embeddedtftp_heur, "TFTP over TURN", "tftp_stun", proto_tftp, HEURISTIC_ENABLE);
|
|
tftp_initialized = TRUE;
|
|
} else {
|
|
dissector_delete_uint_range("udp.port", tftp_port_range, tftp_handle);
|
|
g_free(tftp_port_range);
|
|
}
|
|
|
|
tftp_port_range = range_copy(global_tftp_port_range);
|
|
dissector_add_uint_range("udp.port", tftp_port_range, tftp_handle);
|
|
}
|
|
|
|
/*
|
|
* Editor modelines - http://www.wireshark.org/tools/modelines.html
|
|
*
|
|
* Local variables:
|
|
* c-basic-offset: 2
|
|
* tab-width: 8
|
|
* indent-tabs-mode: nil
|
|
* End:
|
|
*
|
|
* vi: set shiftwidth=2 tabstop=8 expandtab:
|
|
* :indentSize=2:tabSize=8:noTabs=true:
|
|
*/
|