/* packet-ftp.c
* Routines for ftp packet dissection
* Copyright 1999, Richard Sharpe <rsharpe@ns.aus.com>
+ * Copyright 2001, Juan Toledo <toledo@users.sourceforge.net> (Passive FTP)
*
- * $Id: packet-ftp.c,v 1.21 2000/11/10 08:02:34 guy Exp $
+ * $Id: packet-ftp.c,v 1.52 2003/06/10 23:12:15 guy Exp $
*
* Ethereal - Network traffic analyzer
- * By Gerald Combs <gerald@zing.org>
+ * By Gerald Combs <gerald@ethereal.com>
* Copyright 1998 Gerald Combs
*
* Copied from packet-pop.c
- *
+ *
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
- *
+ *
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
- *
+ *
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
#include <stdio.h>
#include <stdlib.h>
-
-#ifdef HAVE_SYS_TYPES_H
-# include <sys/types.h>
-#endif
-
-#ifdef HAVE_NETINET_IN_H
-# include <netinet/in.h>
-#endif
+#include <ctype.h>
#include <string.h>
#include <glib.h>
-#include "packet.h"
-#include "strutil.h"
+#include <epan/packet.h>
+#include <epan/strutil.h>
+#include <epan/conversation.h>
static int proto_ftp = -1;
static int proto_ftp_data = -1;
static int hf_ftp_response = -1;
static int hf_ftp_request = -1;
static int hf_ftp_request_command = -1;
-static int hf_ftp_request_data = -1;
+static int hf_ftp_request_arg = -1;
static int hf_ftp_response_code = -1;
-static int hf_ftp_response_data = -1;
+static int hf_ftp_response_arg = -1;
static gint ett_ftp = -1;
+static gint ett_ftp_reqresp = -1;
static gint ett_ftp_data = -1;
+static dissector_handle_t ftpdata_handle;
+
#define TCP_PORT_FTPDATA 20
#define TCP_PORT_FTP 21
+static const value_string response_table[] = {
+ { 110, "Restart marker reply" },
+ { 120, "Service ready in nnn minutes" },
+ { 125, "Data connection already open; transfer starting" },
+ { 150, "File status okay; about to open data connection" },
+ { 200, "Command okay" },
+ { 202, "Command not implemented, superfluous at this site" },
+ { 211, "System status, or system help reply" },
+ { 212, "Directory status" },
+ { 213, "File status" },
+ { 214, "Help message" },
+ { 215, "NAME system type" },
+ { 220, "Service ready for new user" },
+ { 221, "Service closing control connection" },
+ { 225, "Data connection open; no transfer in progress" },
+ { 226, "Closing data connection" },
+ { 227, "Entering Passive Mode" },
+ { 230, "User logged in, proceed" },
+ { 250, "Requested file action okay, completed" },
+ { 257, "PATHNAME created" },
+ { 331, "User name okay, need password" },
+ { 332, "Need account for login" },
+ { 350, "Requested file action pending further information" },
+ { 421, "Service not available, closing control connection" },
+ { 425, "Can't open data connection" },
+ { 426, "Connection closed; transfer aborted" },
+ { 450, "Requested file action not taken" },
+ { 451, "Requested action aborted: local error in processing" },
+ { 452, "Requested action not taken. Insufficient storage space in system" },
+ { 500, "Syntax error, command unrecognized" },
+ { 501, "Syntax error in parameters or arguments" },
+ { 502, "Command not implemented" },
+ { 503, "Bad sequence of commands" },
+ { 504, "Command not implemented for that parameter" },
+ { 530, "Not logged in" },
+ { 532, "Need account for storing files" },
+ { 550, "Requested action not taken: File unavailable" },
+ { 551, "Requested action aborted: page type unknown" },
+ { 552, "Requested file action aborted: Exceeded storage allocation" },
+ { 553, "Requested action not taken: File name not allowed" },
+ { 0, NULL }
+};
+
+static void
+dissect_ftpdata(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);
+
+/*
+ * Handle a response to a PASV command.
+ *
+ * We ignore the IP address in the reply, and use the address from which
+ * the request came.
+ *
+ * XXX - are there cases where they differ? What if the FTP server is
+ * behind a NAT box, so that the address it puts into the reply isn't
+ * the address at which you should contact it? Do all NAT boxes detect
+ * FTP PASV replies and rewrite the address? (I suspect not.)
+ *
+ * RFC 959 doesn't say much about the syntax of the 227 reply.
+ *
+ * A proposal from Dan Bernstein at
+ *
+ * http://cr.yp.to/ftp/retr.html
+ *
+ * "recommend[s] that clients use the following strategy to parse the
+ * response line: look for the first digit after the initial space; look
+ * for the fourth comma after that digit; read two (possibly negative)
+ * integers, separated by a comma; the TCP port number is p1*256+p2, where
+ * p1 is the first integer modulo 256 and p2 is the second integer modulo
+ * 256."
+ *
+ * wget 1.5.3 looks for a digit, although it doesn't handle negative
+ * integers.
+ *
+ * The FTP code in the source of the cURL library, at
+ *
+ * http://curl.haxx.se/lxr/source/lib/ftp.c
+ *
+ * says that cURL "now scans for a sequence of six comma-separated numbers
+ * and will take them as IP+port indicators"; it loops, doing "sscanf"s
+ * looking for six numbers separated by commas, stepping the start pointer
+ * in the scanf one character at a time - i.e., it tries rather exhaustively.
+ *
+ * An optimization would be to scan for a digit, and start there, and if
+ * the scanf doesn't find six values, scan for the next digit and try
+ * again; this will probably succeed on the first try.
+ *
+ * The cURL code also says that "found reply-strings include":
+ *
+ * "227 Entering Passive Mode (127,0,0,1,4,51)"
+ * "227 Data transfer will passively listen to 127,0,0,1,4,51"
+ * "227 Entering passive mode. 127,0,0,1,4,51"
+ *
+ * so it appears that you can't assume there are parentheses around
+ * the address and port number.
+ */
+static void
+handle_pasv_response(const guchar *line, int linelen, packet_info *pinfo)
+{
+ char *args;
+ char *p;
+ guchar c;
+ int i;
+ int address[4], port[2];
+ guint16 server_port;
+ conversation_t *conversation;
+
+ /*
+ * Copy the rest of the line into a null-terminated buffer.
+ */
+ args = g_malloc(linelen + 1);
+ memcpy(args, line, linelen);
+ args[linelen] = '\0';
+ p = args;
+
+ for (;;) {
+ /*
+ * Look for a digit.
+ */
+ while ((c = *p) != '\0' && !isdigit(c))
+ p++;
+
+ if (*p == '\0') {
+ /*
+ * We ran out of text without finding anything.
+ */
+ break;
+ }
+
+ /*
+ * See if we have six numbers.
+ */
+ i = sscanf(p, "%d,%d,%d,%d,%d,%d",
+ &address[0], &address[1], &address[2], &address[3],
+ &port[0], &port[1]);
+ if (i == 6) {
+ /*
+ * We have a winner!
+ * Set up a conversation, to be dissected as FTP data.
+ */
+ server_port = ((port[0] & 0xFF)<<8) | (port[1] & 0xFF);
+
+ /*
+ * XXX - should this call to "find_conversation()"
+ * just use "pinfo->src" and "server_port", and
+ * wildcard everything else?
+ */
+ conversation = find_conversation(&pinfo->src,
+ &pinfo->dst, PT_TCP, server_port, 0, NO_PORT_B);
+ if (conversation == NULL) {
+ /*
+ * XXX - should this call to
+ * "conversation_new()" just use "pinfo->src"
+ * 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 conversaton code handle
+ * conversations not in the hash table?
+ */
+ conversation = conversation_new(&pinfo->src,
+ &pinfo->dst, PT_TCP, server_port, 0,
+ NO_PORT2);
+ conversation_set_dissector(conversation,
+ ftpdata_handle);
+ }
+ break;
+ }
+
+ /*
+ * Well, that didn't work. Skip the first number we found,
+ * and keep trying.
+ */
+ while ((c = *p) != '\0' && isdigit(c))
+ p++;
+ }
+
+ g_free(args);
+}
+
static void
dissect_ftp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
gboolean is_request;
- proto_tree *ftp_tree;
+ proto_tree *ftp_tree = NULL;
+ proto_tree *reqresp_tree = NULL;
proto_item *ti;
gint offset = 0;
- const u_char *line;
+ const guchar *line;
+ guint32 code;
+ gchar code_str[4];
+ gboolean is_pasv_response = FALSE;
gint next_offset;
int linelen;
int tokenlen;
- const u_char *next_token;
-
- CHECK_DISPLAY_AS_DATA(proto_ftp, tvb, pinfo, tree);
+ const guchar *next_token;
if (pinfo->match_port == pinfo->destport)
is_request = TRUE;
else
is_request = FALSE;
- pinfo->current_proto = "FTP";
-
- if (check_col(pinfo->fd, COL_PROTOCOL))
- col_add_str(pinfo->fd, COL_PROTOCOL, "FTP");
+ if (check_col(pinfo->cinfo, COL_PROTOCOL))
+ 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, offset, -1, &next_offset);
+ linelen = tvb_find_line_end(tvb, offset, -1, &next_offset, FALSE);
line = tvb_get_ptr(tvb, offset, linelen);
- if (check_col(pinfo->fd, COL_INFO)) {
+ if (check_col(pinfo->cinfo, COL_INFO)) {
/*
- * Put the first line from the buffer into the summary.
+ * Put the first line from the buffer into the summary
* (but leave out the line terminator).
*/
- col_add_fstr(pinfo->fd, COL_INFO, "%s: %s",
+ col_add_fstr(pinfo->cinfo, COL_INFO, "%s: %s",
is_request ? "Request" : "Response",
format_text(line, linelen));
}
if (tree) {
- ti = proto_tree_add_item(tree, proto_ftp, tvb, offset,
- tvb_length_remaining(tvb, offset), FALSE);
+ ti = proto_tree_add_item(tree, proto_ftp, tvb, offset, -1,
+ FALSE);
ftp_tree = proto_item_add_subtree(ti, ett_ftp);
if (is_request) {
hf_ftp_response, tvb, 0, 0, TRUE);
}
+ /*
+ * Put the line into the protocol tree.
+ */
+ ti = proto_tree_add_text(ftp_tree, tvb, offset,
+ next_offset - offset, "%s",
+ tvb_format_text(tvb, offset, next_offset - 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 or reply code.
+ * token, add it as the request.
*/
tokenlen = get_token_len(line, line + linelen, &next_token);
if (tokenlen != 0) {
- if (is_request) {
- proto_tree_add_string_format(ftp_tree,
+ if (tree) {
+ proto_tree_add_item(reqresp_tree,
hf_ftp_request_command, tvb, offset,
- tokenlen, line, "Request: %s",
- format_text(line, tokenlen));
- } else {
- proto_tree_add_uint_format(ftp_tree,
- hf_ftp_response_code, tvb, offset,
- tokenlen, atoi(line), "Response: %s",
- format_text(line, tokenlen));
+ tokenlen, FALSE);
}
- offset += next_token - line;
- linelen -= next_token - line;
- line = next_token;
}
+ } 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 && isdigit(line[0]) && isdigit(line[1])
+ && isdigit(line[2])) {
+ /*
+ * One-line reply, or first or last line
+ * of a multi-line reply.
+ */
+ tvb_get_nstringz0(tvb, offset, sizeof(code_str), code_str);
+ code = strtoul(code_str, NULL, 10);
+
+ if (tree) {
+ proto_tree_add_uint(reqresp_tree,
+ hf_ftp_response_code, tvb, offset, 3, code);
+ }
+ /*
+ * See if it's a passive-mode response.
+ *
+ * XXX - check for "229" responses to EPSV
+ * commands, to handle IPv6, as per RFC 2428?
+ *
+ * XXX - does anybody do FOOBAR, as per RFC
+ * 1639, or has that been supplanted by RFC 2428?
+ */
+ if (code == 227)
+ is_pasv_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 += next_token - line;
+ linelen -= next_token - line;
+ line = next_token;
+
+ /*
+ * If this is a PASV response, handle it if we haven't
+ * already processed this frame.
+ */
+ if (!pinfo->fd->flags.visited && is_pasv_response) {
+ if (linelen != 0) {
+ /*
+ * We haven't processed this frame, and it contains
+ * a PASV response; set up a conversation for the
+ * data.
+ */
+ handle_pasv_response(line, linelen, pinfo);
+ }
+ }
+
+ if (tree) {
/*
* Add the rest of the first line as request or
* reply data.
*/
if (linelen != 0) {
if (is_request) {
- proto_tree_add_string_format(ftp_tree,
- hf_ftp_request_data, tvb, offset,
- linelen, line, "Request Arg: %s",
- format_text(line, linelen));
+ proto_tree_add_item(reqresp_tree,
+ hf_ftp_request_arg, tvb, offset,
+ linelen, FALSE);
} else {
- proto_tree_add_string_format(ftp_tree,
- hf_ftp_response_data, tvb, offset,
- linelen, line, "Response Arg: %s",
- format_text(line, linelen));
+ proto_tree_add_item(reqresp_tree,
+ hf_ftp_response_arg, tvb, offset,
+ linelen, FALSE);
}
}
offset = next_offset;
/*
* 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_length_remaining(tvb, offset)) {
+ while (tvb_offset_exists(tvb, offset)) {
/*
* Find the end of the line.
*/
linelen = tvb_find_line_end(tvb, offset, -1,
- &next_offset);
+ &next_offset, FALSE);
/*
* Put this line.
proto_tree *ti, *ftp_data_tree;
int data_length;
- pinfo->current_proto = "FTP-DATA";
-
- if (check_col(pinfo->fd, COL_PROTOCOL))
- col_add_str(pinfo->fd, COL_PROTOCOL, "FTP-DATA");
+ if (check_col(pinfo->cinfo, COL_PROTOCOL))
+ col_set_str(pinfo->cinfo, COL_PROTOCOL, "FTP-DATA");
- if (check_col(pinfo->fd, COL_INFO)) {
- col_add_fstr(pinfo->fd, COL_INFO, "FTP Data: %u bytes",
- tvb_length(tvb));
+ if (check_col(pinfo->cinfo, COL_INFO)) {
+ col_add_fstr(pinfo->cinfo, COL_INFO, "FTP Data: %u bytes",
+ tvb_reported_length(tvb));
}
if (tree) {
data_length = tvb_length(tvb);
- ti = proto_tree_add_item(tree, proto_ftp_data, tvb, 0,
- data_length, FALSE);
+ ti = proto_tree_add_item(tree, proto_ftp_data, tvb, 0, -1,
+ FALSE);
ftp_data_tree = proto_item_add_subtree(ti, ett_ftp_data);
/*
{ &hf_ftp_response,
{ "Response", "ftp.response",
FT_BOOLEAN, BASE_NONE, NULL, 0x0,
- "TRUE if FTP response" }},
+ "TRUE if FTP response", HFILL }},
{ &hf_ftp_request,
{ "Request", "ftp.request",
FT_BOOLEAN, BASE_NONE, NULL, 0x0,
- "TRUE if FTP request" }},
+ "TRUE if FTP request", HFILL }},
{ &hf_ftp_request_command,
{ "Request command", "ftp.request.command",
FT_STRING, BASE_NONE, NULL, 0x0,
- "" }},
+ "", HFILL }},
- { &hf_ftp_request_data,
- { "Request data", "ftp.request.data",
+ { &hf_ftp_request_arg,
+ { "Request arg", "ftp.request.arg",
FT_STRING, BASE_NONE, NULL, 0x0,
- "" }},
+ "", HFILL }},
{ &hf_ftp_response_code,
{ "Response code", "ftp.response.code",
- FT_UINT8, BASE_DEC, NULL, 0x0,
- "" }},
+ FT_UINT32, BASE_DEC, VALS(response_table), 0x0,
+ "", HFILL }},
- { &hf_ftp_response_data,
- { "Response data", "ftp.reponse.data",
+ { &hf_ftp_response_arg,
+ { "Response arg", "ftp.response.arg",
FT_STRING, BASE_NONE, NULL, 0x0,
- "" }}
+ "", HFILL }}
};
static gint *ett[] = {
&ett_ftp,
+ &ett_ftp_reqresp,
&ett_ftp_data,
};
- proto_ftp = proto_register_protocol("File Transfer Protocol (FTP)", "ftp");
- proto_ftp_data = proto_register_protocol("FTP Data", "ftp-data");
+ proto_ftp = proto_register_protocol("File Transfer Protocol (FTP)", "FTP",
+ "ftp");
+ proto_ftp_data = proto_register_protocol("FTP Data", "FTP-DATA", "ftp-data");
proto_register_field_array(proto_ftp, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
+
+ ftpdata_handle = create_dissector_handle(dissect_ftpdata, proto_ftp_data);
}
void
proto_reg_handoff_ftp(void)
{
- dissector_add("tcp.port", TCP_PORT_FTPDATA, &dissect_ftpdata);
- dissector_add("tcp.port", TCP_PORT_FTP, &dissect_ftp);
+ dissector_handle_t ftpdata_handle, ftp_handle;
+
+ ftpdata_handle = create_dissector_handle(dissect_ftpdata, proto_ftp_data);
+ dissector_add("tcp.port", TCP_PORT_FTPDATA, ftpdata_handle);
+ ftp_handle = create_dissector_handle(dissect_ftp, proto_ftp);
+ dissector_add("tcp.port", TCP_PORT_FTP, ftp_handle);
}
git.samba.org / obnox / wireshark / wip.git / blobdiff