forked from osmocom/wireshark
![Evan Huus](/assets/img/avatar_default.png)
Change-Id: Ie40a195db622ebfb096fa5088c5467a1385e69bf Reviewed-on: https://code.wireshark.org/review/9062 Reviewed-by: Evan Huus <eapache@gmail.com>
1064 lines
37 KiB
C
1064 lines
37 KiB
C
/* packet-ftp.c
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* Routines for ftp packet dissection
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* Copyright 1999, Richard Sharpe <rsharpe@ns.aus.com>
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* Copyright 2001, Juan Toledo <toledo@users.sourceforge.net> (Passive FTP)
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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-pop.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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#include "config.h"
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#include <stdio.h>
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#include <stdlib.h>
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#include <epan/packet.h>
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#include <epan/strutil.h>
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#include <epan/conversation.h>
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#include <epan/expert.h>
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#include <epan/addr_resolv.h>
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void proto_register_ftp(void);
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void proto_reg_handoff_ftp(void);
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static int proto_ftp = -1;
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static int proto_ftp_data = -1;
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static int hf_ftp_response = -1;
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static int hf_ftp_request = -1;
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static int hf_ftp_request_command = -1;
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static int hf_ftp_request_arg = -1;
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static int hf_ftp_response_code = -1;
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static int hf_ftp_response_arg = -1;
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static int hf_ftp_pasv_ip = -1 ;
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static int hf_ftp_pasv_port = -1;
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static int hf_ftp_pasv_nat = -1;
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static int hf_ftp_active_ip = -1;
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static int hf_ftp_active_port = -1;
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static int hf_ftp_active_nat = -1;
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static int hf_ftp_eprt_af = -1;
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static int hf_ftp_eprt_ip = -1;
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static int hf_ftp_eprt_ipv6 = -1;
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static int hf_ftp_eprt_port = -1;
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static int hf_ftp_epsv_ip = -1;
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static int hf_ftp_epsv_ipv6 = -1;
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static int hf_ftp_epsv_port = -1;
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static gint ett_ftp = -1;
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static gint ett_ftp_reqresp = -1;
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static expert_field ei_ftp_eprt_args_invalid = EI_INIT;
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static expert_field ei_ftp_epsv_args_invalid = EI_INIT;
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static dissector_handle_t ftpdata_handle;
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#define TCP_PORT_FTPDATA 20
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#define TCP_PORT_FTP 21
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static const value_string response_table[] = {
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{ 110, "Restart marker reply" },
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{ 120, "Service ready in nnn minutes" },
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{ 125, "Data connection already open; transfer starting" },
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{ 150, "File status okay; about to open data connection" },
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{ 200, "Command okay" },
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{ 202, "Command not implemented, superfluous at this site" },
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{ 211, "System status, or system help reply" },
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{ 212, "Directory status" },
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{ 213, "File status" },
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{ 214, "Help message" },
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{ 215, "NAME system type" },
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{ 220, "Service ready for new user" },
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{ 221, "Service closing control connection" },
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{ 225, "Data connection open; no transfer in progress" },
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{ 226, "Closing data connection" },
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{ 227, "Entering Passive Mode" },
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{ 229, "Entering Extended Passive Mode" },
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{ 230, "User logged in, proceed" },
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{ 232, "User logged in, authorized by security data exchange" },
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{ 234, "Security data exchange complete" },
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{ 235, "Security data exchange completed successfully" },
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{ 250, "Requested file action okay, completed" },
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{ 257, "PATHNAME created" },
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{ 331, "User name okay, need password" },
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{ 332, "Need account for login" },
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{ 334, "Requested security mechanism is ok" },
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{ 335, "Security data is acceptable, more is required" },
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{ 336, "Username okay, need password. Challenge is ..." },
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{ 350, "Requested file action pending further information" },
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{ 421, "Service not available, closing control connection" },
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{ 425, "Can't open data connection" },
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{ 426, "Connection closed; transfer aborted" },
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{ 431, "Need some unavailable resource to process security" },
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{ 450, "Requested file action not taken" },
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{ 451, "Requested action aborted: local error in processing" },
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{ 452, "Requested action not taken. Insufficient storage space in system" },
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{ 500, "Syntax error, command unrecognized" },
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{ 501, "Syntax error in parameters or arguments" },
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{ 502, "Command not implemented" },
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{ 503, "Bad sequence of commands" },
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{ 504, "Command not implemented for that parameter" },
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{ 522, "Network protocol not supported" },
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{ 530, "Not logged in" },
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{ 532, "Need account for storing files" },
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{ 533, "Command protection level denied for policy reasons" },
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{ 534, "Request denied for policy reasons" },
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{ 535, "Failed security check (hash, sequence, etc)" },
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{ 536, "Requested PROT level not supported by mechanism" },
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{ 537, "Command protection level not supported by security mechanism" },
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{ 550, "Requested action not taken: File unavailable" },
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{ 551, "Requested action aborted: page type unknown" },
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{ 552, "Requested file action aborted: Exceeded storage allocation" },
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{ 553, "Requested action not taken: File name not allowed" },
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{ 631, "Integrity protected reply" },
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{ 632, "Confidentiality and integrity protected reply" },
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{ 633, "Confidentiality protected reply" },
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{ 0, NULL }
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};
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static value_string_ext response_table_ext = VALUE_STRING_EXT_INIT(response_table);
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#define EPRT_AF_IPv4 1
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#define EPRT_AF_IPv6 2
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static const value_string eprt_af_vals[] = {
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{ EPRT_AF_IPv4, "IPv4" },
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{ EPRT_AF_IPv6, "IPv6" },
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{ 0, NULL }
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};
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/*
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* Parse the address and port information in a PORT command or in the
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* response to a PASV command. Return TRUE if we found an address and
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* port, and supply the address and port; return FALSE if we didn't find
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* them.
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*
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* We ignore the IP address in the reply, and use the address from which
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* the request came.
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*
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* XXX - are there cases where they differ? What if the FTP server is
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* behind a NAT box, so that the address it puts into the reply isn't
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* the address at which you should contact it? Do all NAT boxes detect
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* FTP PASV replies and rewrite the address? (I suspect not.)
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*
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* RFC 959 doesn't say much about the syntax of the 227 reply.
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*
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* A proposal from Dan Bernstein at
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*
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* http://cr.yp.to/ftp/retr.html
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*
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* "recommend[s] that clients use the following strategy to parse the
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* response line: look for the first digit after the initial space; look
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* for the fourth comma after that digit; read two (possibly negative)
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* integers, separated by a comma; the TCP port number is p1*256+p2, where
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* p1 is the first integer modulo 256 and p2 is the second integer modulo
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* 256."
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*
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* wget 1.5.3 looks for a digit, although it doesn't handle negative
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* integers.
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*
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* The FTP code in the source of the cURL library, at
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*
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* http://curl.haxx.se/lxr/source/lib/ftp.c
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*
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* says that cURL "now scans for a sequence of six comma-separated numbers
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* and will take them as IP+port indicators"; it loops, doing "sscanf"s
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* looking for six numbers separated by commas, stepping the start pointer
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* in the scanf one character at a time - i.e., it tries rather exhaustively.
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*
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* An optimization would be to scan for a digit, and start there, and if
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* the scanf doesn't find six values, scan for the next digit and try
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* again; this will probably succeed on the first try.
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*
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* The cURL code also says that "found reply-strings include":
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*
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* "227 Entering Passive Mode (127,0,0,1,4,51)"
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* "227 Data transfer will passively listen to 127,0,0,1,4,51"
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* "227 Entering passive mode. 127,0,0,1,4,51"
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*
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* so it appears that you can't assume there are parentheses around
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* the address and port number.
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*/
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static gboolean
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parse_port_pasv(const guchar *line, int linelen, guint32 *ftp_ip, guint16 *ftp_port,
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guint32 *pasv_offset, guint *ftp_ip_len, guint *ftp_port_len)
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{
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char *args;
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char *p;
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guchar c;
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int i;
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int ip_address[4], port[2];
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gboolean ret = FALSE;
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/*
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* Copy the rest of the line into a null-terminated buffer.
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*/
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args = wmem_strndup(wmem_packet_scope(), line, linelen);
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p = args;
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for (;;) {
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/*
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* Look for a digit.
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*/
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while ((c = *p) != '\0' && !g_ascii_isdigit(c))
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p++;
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if (*p == '\0') {
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/*
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* We ran out of text without finding anything.
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*/
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break;
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}
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/*
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* See if we have six numbers.
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*/
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i = sscanf(p, "%d,%d,%d,%d,%d,%d",
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&ip_address[0], &ip_address[1], &ip_address[2], &ip_address[3],
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&port[0], &port[1]);
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if (i == 6) {
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/*
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* We have a winner!
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*/
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*ftp_port = ((port[0] & 0xFF)<<8) | (port[1] & 0xFF);
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*ftp_ip = g_htonl((ip_address[0] << 24) | (ip_address[1] <<16) | (ip_address[2] <<8) | ip_address[3]);
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*pasv_offset = (guint32)(p - args);
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*ftp_port_len = (port[0] < 10 ? 1 : (port[0] < 100 ? 2 : 3 )) + 1 +
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(port[1] < 10 ? 1 : (port[1] < 100 ? 2 : 3 ));
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*ftp_ip_len = (ip_address[0] < 10 ? 1 : (ip_address[0] < 100 ? 2 : 3)) + 1 +
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(ip_address[1] < 10 ? 1 : (ip_address[1] < 100 ? 2 : 3)) + 1 +
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(ip_address[2] < 10 ? 1 : (ip_address[2] < 100 ? 2 : 3)) + 1 +
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(ip_address[3] < 10 ? 1 : (ip_address[3] < 100 ? 2 : 3));
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ret = TRUE;
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break;
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}
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/*
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* Well, that didn't work. Skip the first number we found,
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* and keep trying.
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*/
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while ((c = *p) != '\0' && g_ascii_isdigit(c))
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p++;
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}
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return ret;
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}
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static gboolean
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isvalid_rfc2428_delimiter(const guchar c)
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{
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/* RFC2428 sect. 2 states rules for a valid delimiter */
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const gchar *forbidden = "0123456789abcdef.:";
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if (!g_ascii_isgraph(c))
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return FALSE;
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if (strchr(forbidden, g_ascii_tolower(c)))
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return FALSE;
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return TRUE;
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}
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/*
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* RFC2428 states...
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*
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* AF Number Protocol
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* --------- --------
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* 1 Internet Protocol, Version 4
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* 2 Internet Protocol, Version 6
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*
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* AF Number Address Format Example
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* --------- -------------- -------
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* 1 dotted decimal 132.235.1.2
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* 2 IPv6 string 1080::8:800:200C:417A
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* representations
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* defined in
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*
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* The following are sample EPRT commands:
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* EPRT |1|132.235.1.2|6275|
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* EPRT |2|1080::8:800:200C:417A|5282|
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*
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* The first command specifies that the server should use IPv4 to open a
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* data connection to the host "132.235.1.2" on TCP port 6275. The
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* second command specifies that the server should use the IPv6 network
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* protocol and the network address "1080::8:800:200C:417A" to open a
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* TCP data connection on port 5282.
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*
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* ... which means in fact that RFC2428 is capable to handle both,
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* IPv4 and IPv6 so we have to care about the address family and properly
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* act depending on it.
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*
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*/
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static gboolean
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parse_eprt_request(const guchar* line, gint linelen, guint32 *eprt_af,
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guint32 *eprt_ip, guint16 *eprt_ipv6, guint16 *ftp_port,
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guint32 *eprt_ip_len, guint32 *ftp_port_len)
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{
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gint delimiters_seen = 0;
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gchar delimiter;
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gint fieldlen;
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gchar *field;
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gint n;
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gint lastn;
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char *args, *p;
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gboolean ret = TRUE;
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/* line contains the EPRT parameters, we need at least the 4 delimiters */
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if (!line || linelen<4)
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return FALSE;
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/* Copy the rest of the line into a null-terminated buffer. */
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args = wmem_strndup(wmem_packet_scope(), line, linelen);
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p = args;
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/*
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* Handle a NUL being in the line; if there's a NUL in the line,
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* strlen(args) will terminate at the NUL and will thus return
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* a value less than linelen.
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*/
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if ((gint)strlen(args) < linelen)
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linelen = (gint)strlen(args);
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/*
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* RFC2428 sect. 2 states ...
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*
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* The EPRT command keyword MUST be followed by a single space (ASCII
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* 32). Following the space, a delimiter character (<d>) MUST be
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* specified.
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*
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* ... the preceding <space> is already stripped so we know that the first
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* character must be the delimiter and has just to be checked to be valid.
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*/
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if (!isvalid_rfc2428_delimiter(*p))
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return FALSE; /* EPRT command does not follow a vaild delimiter;
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* malformed EPRT command - immediate escape */
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delimiter = *p;
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/* Validate that the delimiter occurs 4 times in the string */
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for (n = 0; n < linelen; n++) {
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if (*(p+n) == delimiter)
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delimiters_seen++;
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}
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if (delimiters_seen != 4)
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return FALSE; /* delimiter doesn't occur 4 times
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* probably no EPRT request - immediate escape */
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/* we know that the first character is a delimiter... */
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delimiters_seen = 1;
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lastn = 0;
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/* ... so we can start searching from the 2nd onwards */
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for (n=1; n < linelen; n++) {
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if (*(p+n) != delimiter)
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continue;
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/* we found a delimiter */
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delimiters_seen++;
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fieldlen = n - lastn - 1;
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if (fieldlen<=0)
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return FALSE; /* all fields must have data in them */
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field = p + lastn + 1;
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if (delimiters_seen == 2) { /* end of address family field */
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gchar *af_str;
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af_str = wmem_strndup(wmem_packet_scope(), field, fieldlen);
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*eprt_af = atoi(af_str);
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}
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else if (delimiters_seen == 3) {/* end of IP address field */
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gchar *ip_str;
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ip_str = wmem_strndup(wmem_packet_scope(), field, fieldlen);
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if (*eprt_af == EPRT_AF_IPv4) {
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if (str_to_ip(ip_str, eprt_ip))
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ret = TRUE;
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else
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ret = FALSE;
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}
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else if (*eprt_af == EPRT_AF_IPv6) {
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if (str_to_ip6(ip_str, eprt_ipv6))
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ret = TRUE;
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else
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ret = FALSE;
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}
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else
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return FALSE; /* invalid/unknown address family */
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*eprt_ip_len = fieldlen;
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}
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else if (delimiters_seen == 4) {/* end of port field */
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gchar *pt_str;
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pt_str = wmem_strndup(wmem_packet_scope(), field, fieldlen);
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*ftp_port = atoi(pt_str);
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*ftp_port_len = fieldlen;
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}
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lastn = n;
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}
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return ret;
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}
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/*
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* RFC2428 states ....
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*
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* The first two fields contained in the parenthesis MUST be blank. The
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* third field MUST be the string representation of the TCP port number
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* on which the server is listening for a data connection.
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*
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* The network protocol used by the data connection will be the same network
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* protocol used by the control connection. In addition, the network
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* address used to establish the data connection will be the same
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* network address used for the control connection.
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*
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* An example response string follows:
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*
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* Entering Extended Passive Mode (|||6446|)
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*
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* ... which in fact means that again both address families IPv4 and IPv6
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* are supported. But gladly it's not necessary to parse because it doesn't
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* occur in EPSV responses. We can leverage ftp_ip_address which is
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* protocol independent and already set.
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*
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*/
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static gboolean
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parse_extended_pasv_response(const guchar *line, gint linelen, guint16 *ftp_port,
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guint *pasv_offset, guint *ftp_port_len)
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{
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gint n;
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gchar *args;
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gchar *p;
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gchar *e;
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guchar c;
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gboolean ret = FALSE;
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gboolean delimiters_seen = FALSE;
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/*
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* Copy the rest of the line into a null-terminated buffer.
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*/
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args = wmem_strndup(wmem_packet_scope(), line, linelen);
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p = args;
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/*
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* Look for ( <d> <d> <d>
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(Try to cope with '(' in description)
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*/
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for (; !delimiters_seen;) {
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guchar delimiter = '\0';
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while ((c = *p) != '\0' && (c != '('))
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p++;
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if (*p == '\0') {
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return FALSE;
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}
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/* Skip '(' */
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p++;
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/* Make sure same delimiter is used 3 times */
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for (n=0; n<3; n++) {
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if ((c = *p) != '\0') {
|
|
if (delimiter == '\0' && isvalid_rfc2428_delimiter(c)) {
|
|
delimiter = c;
|
|
}
|
|
if (c != delimiter) {
|
|
break;
|
|
}
|
|
p++;
|
|
}
|
|
else {
|
|
break;
|
|
}
|
|
}
|
|
delimiters_seen = TRUE;
|
|
}
|
|
|
|
/*
|
|
* Should now be at digits.
|
|
*/
|
|
if (*p != '\0') {
|
|
/*
|
|
* We didn't run out of text without finding anything.
|
|
*/
|
|
*ftp_port = atoi(p);
|
|
*pasv_offset = (guint32)(p - args);
|
|
|
|
ret = TRUE;
|
|
|
|
/* get port string length */
|
|
if ((e=strchr(p,')')) == NULL) {
|
|
ret = FALSE;
|
|
}
|
|
else {
|
|
*ftp_port_len = (guint)(--e - p);
|
|
}
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
|
|
static void
|
|
dissect_ftp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
|
|
{
|
|
gboolean is_request;
|
|
proto_tree *ftp_tree;
|
|
proto_tree *reqresp_tree;
|
|
proto_item *ti, *hidden_item;
|
|
gint offset;
|
|
const guchar *line;
|
|
guint32 code;
|
|
gchar code_str[4];
|
|
gboolean is_port_request = FALSE;
|
|
gboolean is_eprt_request = FALSE;
|
|
gboolean is_pasv_response = FALSE;
|
|
gboolean is_epasv_response = FALSE;
|
|
gint next_offset;
|
|
int linelen;
|
|
int tokenlen = 0;
|
|
const guchar *next_token;
|
|
guint32 pasv_ip;
|
|
guint32 pasv_offset;
|
|
guint32 ftp_ip;
|
|
guint32 ftp_ip_len;
|
|
guint32 eprt_offset;
|
|
guint32 eprt_af = 0;
|
|
guint32 eprt_ip;
|
|
guint16 eprt_ipv6[8];
|
|
guint32 eprt_ip_len = 0;
|
|
guint16 ftp_port;
|
|
guint32 ftp_port_len;
|
|
address ftp_ip_address;
|
|
gboolean ftp_nat;
|
|
conversation_t *conversation;
|
|
|
|
ftp_ip_address = pinfo->src;
|
|
|
|
if (pinfo->match_uint == pinfo->destport)
|
|
is_request = TRUE;
|
|
else
|
|
is_request = FALSE;
|
|
|
|
col_set_str(pinfo->cinfo, COL_PROTOCOL, "FTP");
|
|
|
|
/*
|
|
* Find the end of the first line.
|
|
*
|
|
* Note that "tvb_find_line_end()" will return a value that is
|
|
* not longer than what's in the buffer, so the "tvb_get_ptr()"
|
|
* call won't throw an exception.
|
|
*/
|
|
linelen = tvb_find_line_end(tvb, 0, -1, &next_offset, FALSE);
|
|
line = tvb_get_ptr(tvb, 0, linelen);
|
|
|
|
/*
|
|
* Put the first line from the buffer into the summary
|
|
* (but leave out the line terminator).
|
|
*/
|
|
col_add_fstr(pinfo->cinfo, COL_INFO, "%s: %s",
|
|
is_request ? "Request" : "Response",
|
|
format_text(line, linelen));
|
|
|
|
ti = proto_tree_add_item(tree, proto_ftp, tvb, 0, -1, ENC_NA);
|
|
ftp_tree = proto_item_add_subtree(ti, ett_ftp);
|
|
|
|
hidden_item = proto_tree_add_boolean(ftp_tree,
|
|
hf_ftp_request, tvb, 0, 0, is_request);
|
|
PROTO_ITEM_SET_HIDDEN(hidden_item);
|
|
hidden_item = proto_tree_add_boolean(ftp_tree,
|
|
hf_ftp_response, tvb, 0, 0, is_request == FALSE);
|
|
PROTO_ITEM_SET_HIDDEN(hidden_item);
|
|
|
|
/* Put the line into the protocol tree. */
|
|
ti = proto_tree_add_format_text(ftp_tree, tvb, 0, next_offset);
|
|
reqresp_tree = proto_item_add_subtree(ti, ett_ftp_reqresp);
|
|
|
|
if (is_request) {
|
|
/*
|
|
* Extract the first token, and, if there is a first
|
|
* token, add it as the request.
|
|
*/
|
|
tokenlen = get_token_len(line, line + linelen, &next_token);
|
|
if (tokenlen != 0) {
|
|
proto_tree_add_item(reqresp_tree, hf_ftp_request_command,
|
|
tvb, 0, tokenlen, ENC_ASCII|ENC_NA);
|
|
if (strncmp(line, "PORT", tokenlen) == 0)
|
|
is_port_request = TRUE;
|
|
/*
|
|
* EPRT request command, as per RFC 2428
|
|
*/
|
|
else if (strncmp(line, "EPRT", tokenlen) == 0)
|
|
is_eprt_request = TRUE;
|
|
}
|
|
} else {
|
|
/*
|
|
* This is a response; the response code is 3 digits,
|
|
* followed by a space or hyphen, possibly followed by
|
|
* text.
|
|
*
|
|
* If the line doesn't start with 3 digits, it's part of
|
|
* a continuation.
|
|
*
|
|
* XXX - keep track of state in the first pass, and
|
|
* treat non-continuation lines not beginning with digits
|
|
* as errors?
|
|
*/
|
|
if (linelen >= 3 && g_ascii_isdigit(line[0]) && g_ascii_isdigit(line[1])
|
|
&& g_ascii_isdigit(line[2])) {
|
|
/*
|
|
* One-line reply, or first or last line
|
|
* of a multi-line reply.
|
|
*/
|
|
tvb_get_nstringz0(tvb, 0, sizeof(code_str), code_str);
|
|
code = (guint32)strtoul(code_str, NULL, 10);
|
|
|
|
proto_tree_add_uint(reqresp_tree,
|
|
hf_ftp_response_code, tvb, 0, 3, code);
|
|
|
|
/*
|
|
* See if it's a passive-mode response.
|
|
*
|
|
* XXX - does anybody do FOOBAR, as per RFC
|
|
* 1639, or has that been supplanted by RFC 2428?
|
|
*/
|
|
if (code == 227)
|
|
is_pasv_response = TRUE;
|
|
|
|
/*
|
|
* Responses to EPSV command, as per RFC 2428
|
|
*/
|
|
if (code == 229)
|
|
is_epasv_response = TRUE;
|
|
|
|
/*
|
|
* Skip the 3 digits and, if present, the
|
|
* space or hyphen.
|
|
*/
|
|
if (linelen >= 4)
|
|
next_token = line + 4;
|
|
else
|
|
next_token = line + linelen;
|
|
} else {
|
|
/*
|
|
* Line doesn't start with 3 digits; assume it's
|
|
* a line in the middle of a multi-line reply.
|
|
*/
|
|
next_token = line;
|
|
}
|
|
}
|
|
|
|
offset = (gint) (next_token - line);
|
|
linelen -= (int) (next_token - line);
|
|
line = next_token;
|
|
|
|
/*
|
|
* Add the rest of the first line as request or
|
|
* reply data.
|
|
*/
|
|
if (linelen != 0) {
|
|
if (is_request) {
|
|
proto_tree_add_item(reqresp_tree,
|
|
hf_ftp_request_arg, tvb, offset,
|
|
linelen, ENC_ASCII|ENC_NA);
|
|
} else {
|
|
proto_tree_add_item(reqresp_tree,
|
|
hf_ftp_response_arg, tvb, offset,
|
|
linelen, ENC_ASCII|ENC_NA);
|
|
}
|
|
}
|
|
offset = next_offset;
|
|
|
|
/*
|
|
* If this is a PORT request or a PASV response, handle it.
|
|
*/
|
|
if (is_port_request) {
|
|
if (parse_port_pasv(line, linelen, &ftp_ip, &ftp_port, &pasv_offset, &ftp_ip_len, &ftp_port_len)) {
|
|
proto_tree_add_ipv4(reqresp_tree, hf_ftp_active_ip,
|
|
tvb, pasv_offset + (tokenlen+1) , ftp_ip_len, ftp_ip);
|
|
proto_tree_add_uint(reqresp_tree, hf_ftp_active_port,
|
|
tvb, pasv_offset + 1 + (tokenlen+1) + ftp_ip_len, ftp_port_len, ftp_port);
|
|
SET_ADDRESS(&ftp_ip_address, AT_IPv4, 4, (const guint8 *)&ftp_ip);
|
|
ftp_nat = !ADDRESSES_EQUAL(&pinfo->src, &ftp_ip_address);
|
|
if (ftp_nat) {
|
|
proto_tree_add_boolean(reqresp_tree, hf_ftp_active_nat,
|
|
tvb, 0, 0, ftp_nat);
|
|
}
|
|
}
|
|
}
|
|
|
|
if (is_pasv_response) {
|
|
if (linelen != 0) {
|
|
/*
|
|
* This frame contains a PASV response; set up a
|
|
* conversation for the data.
|
|
*/
|
|
if (parse_port_pasv(line, linelen, &pasv_ip, &ftp_port, &pasv_offset, &ftp_ip_len, &ftp_port_len)) {
|
|
proto_tree_add_ipv4(reqresp_tree, hf_ftp_pasv_ip,
|
|
tvb, pasv_offset + 4, ftp_ip_len, pasv_ip);
|
|
proto_tree_add_uint(reqresp_tree, hf_ftp_pasv_port,
|
|
tvb, pasv_offset + 4 + 1 + ftp_ip_len, ftp_port_len, ftp_port);
|
|
SET_ADDRESS(&ftp_ip_address, AT_IPv4, 4,
|
|
(const guint8 *)&pasv_ip);
|
|
ftp_nat = !ADDRESSES_EQUAL(&pinfo->src, &ftp_ip_address);
|
|
if (ftp_nat) {
|
|
proto_tree_add_boolean(reqresp_tree, hf_ftp_pasv_nat,
|
|
tvb, 0, 0, ftp_nat);
|
|
}
|
|
|
|
/*
|
|
* We use "ftp_ip_address", so that if
|
|
* we're NAT'd we look for the un-NAT'd
|
|
* connection.
|
|
*
|
|
* XXX - should this call to
|
|
* "find_conversation()" just use
|
|
* "ftp_ip_address" and "server_port", and
|
|
* wildcard everything else?
|
|
*/
|
|
conversation = find_conversation(pinfo->fd->num, &ftp_ip_address,
|
|
&pinfo->dst, PT_TCP, ftp_port, 0,
|
|
NO_PORT_B);
|
|
if (conversation == NULL) {
|
|
/*
|
|
* XXX - should this call to "conversation_new()"
|
|
* just use "ftp_ip_address" and "server_port",
|
|
* and wildcard everything else?
|
|
*
|
|
* XXX - what if we did find a conversation? As
|
|
* we create it only on the first pass through the
|
|
* packets, if we find one, it's presumably an
|
|
* unrelated conversation. Should we remove the
|
|
* old one from the hash table and put this one in
|
|
* its place? Can the conversation code handle
|
|
* conversations not in the hash table? Or should
|
|
* we make conversations support start and end
|
|
* frames, as circuits do, and treat this as an
|
|
* indication that one conversation was closed and
|
|
* a new one was opened?
|
|
*/
|
|
conversation = conversation_new(
|
|
pinfo->fd->num, &ftp_ip_address, &pinfo->dst,
|
|
PT_TCP, ftp_port, 0, NO_PORT2);
|
|
conversation_set_dissector(conversation, ftpdata_handle);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if (is_eprt_request) {
|
|
/*
|
|
* RFC2428 - sect. 2
|
|
* This frame contains a EPRT request; let's dissect it and set up a
|
|
* conversation for the data connection.
|
|
*/
|
|
if (parse_eprt_request(line, linelen,
|
|
&eprt_af, &eprt_ip, eprt_ipv6, &ftp_port,
|
|
&eprt_ip_len, &ftp_port_len)) {
|
|
|
|
/* since parse_eprt_request() returned TRUE,
|
|
we know that we have a valid address family */
|
|
eprt_offset = tokenlen + 1 + 1; /* token, space, 1st delimiter */
|
|
proto_tree_add_uint(reqresp_tree, hf_ftp_eprt_af, tvb,
|
|
eprt_offset, 1, eprt_af);
|
|
eprt_offset += 1 + 1; /* addr family, 2nd delimiter */
|
|
|
|
if (eprt_af == EPRT_AF_IPv4) {
|
|
proto_tree_add_ipv4(reqresp_tree, hf_ftp_eprt_ip,
|
|
tvb, eprt_offset, eprt_ip_len, eprt_ip);
|
|
SET_ADDRESS(&ftp_ip_address, AT_IPv4, 4,
|
|
(const guint8 *)&eprt_ip);
|
|
}
|
|
else if (eprt_af == EPRT_AF_IPv6) {
|
|
proto_tree_add_ipv6(reqresp_tree, hf_ftp_eprt_ipv6,
|
|
tvb, eprt_offset, eprt_ip_len, (const guint8 *)eprt_ipv6);
|
|
SET_ADDRESS(&ftp_ip_address, AT_IPv6, 16,
|
|
(const guint8 *)&eprt_ipv6);
|
|
}
|
|
eprt_offset += eprt_ip_len + 1; /* addr, 3rd delimiter */
|
|
|
|
proto_tree_add_uint(reqresp_tree, hf_ftp_eprt_port,
|
|
tvb, eprt_offset, ftp_port_len, ftp_port);
|
|
|
|
/* Find/create conversation for data */
|
|
conversation = find_conversation(pinfo->fd->num,
|
|
&pinfo->src, &ftp_ip_address,
|
|
PT_TCP, ftp_port, 0, NO_PORT_B);
|
|
if (conversation == NULL) {
|
|
conversation = conversation_new(
|
|
pinfo->fd->num, &pinfo->src, &ftp_ip_address,
|
|
PT_TCP, ftp_port, 0, NO_PORT2);
|
|
conversation_set_dissector(conversation,
|
|
ftpdata_handle);
|
|
}
|
|
}
|
|
else {
|
|
proto_tree_add_expert(reqresp_tree, pinfo, &ei_ftp_eprt_args_invalid,
|
|
tvb, offset - linelen - 1, linelen);
|
|
}
|
|
}
|
|
|
|
if (is_epasv_response) {
|
|
if (linelen != 0) {
|
|
proto_item *addr_it;
|
|
/*
|
|
* RFC2428 - sect. 3
|
|
* This frame contains an EPSV response; set up a
|
|
* conversation for the data.
|
|
*/
|
|
if (parse_extended_pasv_response(line, linelen,
|
|
&ftp_port, &pasv_offset, &ftp_port_len)) {
|
|
/* Add IP address and port number to tree */
|
|
|
|
if (ftp_ip_address.type == AT_IPv4) {
|
|
guint32 addr;
|
|
memcpy(&addr, ftp_ip_address.data, 4);
|
|
addr_it = proto_tree_add_ipv4(reqresp_tree,
|
|
hf_ftp_epsv_ip, tvb, 0, 0, addr);
|
|
PROTO_ITEM_SET_GENERATED(addr_it);
|
|
}
|
|
else if (ftp_ip_address.type == AT_IPv6) {
|
|
addr_it = proto_tree_add_ipv6(reqresp_tree,
|
|
hf_ftp_epsv_ipv6, tvb, 0, 0,
|
|
(const guint8*)ftp_ip_address.data);
|
|
PROTO_ITEM_SET_GENERATED(addr_it);
|
|
}
|
|
|
|
proto_tree_add_uint(reqresp_tree,
|
|
hf_ftp_epsv_port, tvb, pasv_offset + 4,
|
|
ftp_port_len, ftp_port);
|
|
|
|
/* Find/create conversation for data */
|
|
conversation = find_conversation(pinfo->fd->num, &ftp_ip_address,
|
|
&pinfo->dst, PT_TCP, ftp_port, 0,
|
|
NO_PORT_B);
|
|
if (conversation == NULL) {
|
|
conversation = conversation_new(
|
|
pinfo->fd->num, &ftp_ip_address, &pinfo->dst,
|
|
PT_TCP, ftp_port, 0, NO_PORT2);
|
|
conversation_set_dissector(conversation,
|
|
ftpdata_handle);
|
|
}
|
|
}
|
|
else {
|
|
proto_tree_add_expert(reqresp_tree, pinfo, &ei_ftp_epsv_args_invalid,
|
|
tvb, offset - linelen - 1, linelen);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Show the rest of the request or response as text,
|
|
* a line at a time.
|
|
* XXX - only if there's a continuation indicator?
|
|
*/
|
|
while (tvb_offset_exists(tvb, offset)) {
|
|
/*
|
|
* Find the end of the line.
|
|
*/
|
|
tvb_find_line_end(tvb, offset, -1, &next_offset, FALSE);
|
|
|
|
/*
|
|
* Put this line.
|
|
*/
|
|
proto_tree_add_format_text(ftp_tree, tvb, offset,
|
|
next_offset - offset);
|
|
offset = next_offset;
|
|
}
|
|
}
|
|
|
|
static void
|
|
dissect_ftpdata(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
|
|
{
|
|
proto_item *ti;
|
|
int data_length;
|
|
gboolean is_text = TRUE;
|
|
gint check_chars, i;
|
|
|
|
col_set_str(pinfo->cinfo, COL_PROTOCOL, "FTP-DATA");
|
|
|
|
col_add_fstr(pinfo->cinfo, COL_INFO, "FTP Data: %u bytes",
|
|
tvb_reported_length(tvb));
|
|
|
|
data_length = tvb_captured_length(tvb);
|
|
|
|
ti = proto_tree_add_item(tree, proto_ftp_data, tvb, 0, -1, ENC_NA);
|
|
|
|
/* Check the first few chars to see whether it looks like a text file or not */
|
|
check_chars = MIN(10, data_length);
|
|
for (i=0; i < check_chars; i++) {
|
|
if (!g_ascii_isprint(tvb_get_guint8(tvb, i))) {
|
|
is_text = FALSE;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (is_text) {
|
|
/* Show as string, but don't format more text than will be displayed */
|
|
proto_item_append_text(ti, " (%s)", tvb_format_text(tvb, 0, MIN(data_length, ITEM_LABEL_LENGTH)));
|
|
}
|
|
else {
|
|
/* Assume binary, just show the number of bytes */
|
|
proto_item_append_text(ti, " (%u bytes data)", data_length);
|
|
}
|
|
}
|
|
|
|
void
|
|
proto_register_ftp(void)
|
|
{
|
|
static hf_register_info hf[] = {
|
|
{ &hf_ftp_response,
|
|
{ "Response", "ftp.response",
|
|
FT_BOOLEAN, BASE_NONE, NULL, 0x0,
|
|
"TRUE if FTP response", HFILL }},
|
|
|
|
{ &hf_ftp_request,
|
|
{ "Request", "ftp.request",
|
|
FT_BOOLEAN, BASE_NONE, NULL, 0x0,
|
|
"TRUE if FTP request", HFILL }},
|
|
|
|
{ &hf_ftp_request_command,
|
|
{ "Request command", "ftp.request.command",
|
|
FT_STRING, BASE_NONE, NULL, 0x0,
|
|
NULL, HFILL }},
|
|
|
|
{ &hf_ftp_request_arg,
|
|
{ "Request arg", "ftp.request.arg",
|
|
FT_STRING, BASE_NONE, NULL, 0x0,
|
|
NULL, HFILL }},
|
|
|
|
{ &hf_ftp_response_code,
|
|
{ "Response code", "ftp.response.code",
|
|
FT_UINT32, BASE_DEC|BASE_EXT_STRING, &response_table_ext, 0x0,
|
|
NULL, HFILL }},
|
|
|
|
{ &hf_ftp_response_arg,
|
|
{ "Response arg", "ftp.response.arg",
|
|
FT_STRING, BASE_NONE, NULL, 0x0,
|
|
NULL, HFILL }},
|
|
|
|
{ &hf_ftp_pasv_ip,
|
|
{ "Passive IP address", "ftp.passive.ip",
|
|
FT_IPv4, BASE_NONE, NULL,0x0,
|
|
"Passive IP address (check NAT)", HFILL}},
|
|
|
|
{ &hf_ftp_pasv_port,
|
|
{ "Passive port", "ftp.passive.port",
|
|
FT_UINT16, BASE_DEC, NULL,0x0,
|
|
"Passive FTP server port", HFILL }},
|
|
|
|
{ &hf_ftp_pasv_nat,
|
|
{"Passive IP NAT", "ftp.passive.nat",
|
|
FT_BOOLEAN, BASE_NONE, NULL, 0x0,
|
|
"NAT is active SIP and passive IP different", HFILL }},
|
|
|
|
{ &hf_ftp_active_ip,
|
|
{ "Active IP address", "ftp.active.cip",
|
|
FT_IPv4, BASE_NONE, NULL, 0x0,
|
|
"Active FTP client IP address", HFILL }},
|
|
|
|
{ &hf_ftp_active_port,
|
|
{"Active port", "ftp.active.port",
|
|
FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
"Active FTP client port", HFILL }},
|
|
|
|
{ &hf_ftp_active_nat,
|
|
{ "Active IP NAT", "ftp.active.nat",
|
|
FT_BOOLEAN, BASE_NONE, NULL, 0x0,
|
|
"NAT is active", HFILL}},
|
|
|
|
{ &hf_ftp_eprt_af,
|
|
{ "Extended active address family", "ftp.eprt.af",
|
|
FT_UINT8, BASE_DEC, VALS(eprt_af_vals), 0,
|
|
NULL, HFILL }},
|
|
|
|
{ &hf_ftp_eprt_ip,
|
|
{ "Extended active IP address", "ftp.eprt.ip",
|
|
FT_IPv4, BASE_NONE, NULL, 0,
|
|
"Extended active FTP client IPv4 address", HFILL }},
|
|
|
|
{ &hf_ftp_eprt_ipv6,
|
|
{ "Extended active IPv6 address", "ftp.eprt.ipv6",
|
|
FT_IPv6, BASE_NONE, NULL, 0,
|
|
"Extended active FTP client IPv6 address", HFILL }},
|
|
|
|
{ &hf_ftp_eprt_port,
|
|
{ "Extended active port", "ftp.eprt.port",
|
|
FT_UINT16, BASE_DEC, NULL, 0,
|
|
"Extended active FTP client listener port", HFILL }},
|
|
|
|
{ &hf_ftp_epsv_ip,
|
|
{ "Extended passive IPv4 address", "ftp.epsv.ip",
|
|
FT_IPv4, BASE_NONE, NULL, 0,
|
|
"Extended passive FTP server IPv4 address", HFILL }},
|
|
|
|
{ &hf_ftp_epsv_ipv6,
|
|
{ "Extended passive IPv6 address", "ftp.epsv.ipv6",
|
|
FT_IPv6, BASE_NONE, NULL, 0,
|
|
"Extended passive FTP server IPv6 address", HFILL }},
|
|
|
|
{ &hf_ftp_epsv_port,
|
|
{ "Extended passive port", "ftp.epsv.port",
|
|
FT_UINT16, BASE_DEC, NULL, 0,
|
|
"Extended passive FTP server port", HFILL }}
|
|
|
|
};
|
|
static gint *ett[] = {
|
|
&ett_ftp,
|
|
&ett_ftp_reqresp
|
|
};
|
|
|
|
static ei_register_info ei[] = {
|
|
{ &ei_ftp_eprt_args_invalid, { "ftp.eprt.args_invalid", PI_MALFORMED, PI_WARN, "EPRT arguments must have the form: |<family>|<addr>|<port>|", EXPFILL }},
|
|
{ &ei_ftp_epsv_args_invalid, { "ftp.epsv.args_invalid", PI_MALFORMED, PI_WARN, "EPSV arguments must have the form (|||<port>|)", EXPFILL }},
|
|
};
|
|
|
|
expert_module_t* expert_ftp;
|
|
|
|
proto_ftp = proto_register_protocol("File Transfer Protocol (FTP)", "FTP", "ftp");
|
|
|
|
register_dissector("ftp", dissect_ftp, proto_ftp);
|
|
proto_ftp_data = proto_register_protocol("FTP Data", "FTP-DATA", "ftp-data");
|
|
register_dissector("ftp-data", dissect_ftpdata, proto_ftp_data);
|
|
proto_register_field_array(proto_ftp, hf, array_length(hf));
|
|
proto_register_subtree_array(ett, array_length(ett));
|
|
expert_ftp = expert_register_protocol(proto_ftp);
|
|
expert_register_field_array(expert_ftp, ei, array_length(ei));
|
|
}
|
|
|
|
void
|
|
proto_reg_handoff_ftp(void)
|
|
{
|
|
dissector_handle_t ftp_handle;
|
|
|
|
ftpdata_handle = find_dissector("ftp-data");
|
|
dissector_add_uint("tcp.port", TCP_PORT_FTPDATA, ftpdata_handle);
|
|
ftp_handle = find_dissector("ftp");
|
|
dissector_add_uint("tcp.port", TCP_PORT_FTP, ftp_handle);
|
|
}
|
|
|
|
/*
|
|
* Editor modelines - http://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:
|
|
*/
|