1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
|
/*
* Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996, 1997
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that: (1) source code distributions
* retain the above copyright notice and this paragraph in its entirety, (2)
* distributions including binary code include the above copyright notice and
* this paragraph in its entirety in the documentation or other materials
* provided with the distribution, and (3) all advertising materials mentioning
* features or use of this software display the following acknowledgement:
* ``This product includes software developed by the University of California,
* Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
* the University nor the names of its contributors may be used to endorse
* or promote products derived from this software without specific prior
* written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
/* \summary: Trivial File Transfer Protocol (TFTP) printer */
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <netdissect-stdinc.h>
#include <string.h>
#include "netdissect.h"
#include "extract.h"
/*
* Trivial File Transfer Protocol (IEN-133)
*/
/*
* Packet types.
*/
#define RRQ 01 /* read request */
#define WRQ 02 /* write request */
#define DATA 03 /* data packet */
#define ACK 04 /* acknowledgement */
#define TFTP_ERROR 05 /* error code */
#define OACK 06 /* option acknowledgement */
/*
* Error codes.
*/
#define EUNDEF 0 /* not defined */
#define ENOTFOUND 1 /* file not found */
#define EACCESS 2 /* access violation */
#define ENOSPACE 3 /* disk full or allocation exceeded */
#define EBADOP 4 /* illegal TFTP operation */
#define EBADID 5 /* unknown transfer ID */
#define EEXISTS 6 /* file already exists */
#define ENOUSER 7 /* no such user */
static const char tstr[] = " [|tftp]";
/* op code to string mapping */
static const struct tok op2str[] = {
{ RRQ, "RRQ" }, /* read request */
{ WRQ, "WRQ" }, /* write request */
{ DATA, "DATA" }, /* data packet */
{ ACK, "ACK" }, /* acknowledgement */
{ TFTP_ERROR, "ERROR" }, /* error code */
{ OACK, "OACK" }, /* option acknowledgement */
{ 0, NULL }
};
/* error code to string mapping */
static const struct tok err2str[] = {
{ EUNDEF, "EUNDEF" }, /* not defined */
{ ENOTFOUND, "ENOTFOUND" }, /* file not found */
{ EACCESS, "EACCESS" }, /* access violation */
{ ENOSPACE, "ENOSPACE" }, /* disk full or allocation exceeded */
{ EBADOP, "EBADOP" }, /* illegal TFTP operation */
{ EBADID, "EBADID" }, /* unknown transfer ID */
{ EEXISTS, "EEXISTS" }, /* file already exists */
{ ENOUSER, "ENOUSER" }, /* no such user */
{ 0, NULL }
};
/*
* Print trivial file transfer program requests
*/
void
tftp_print(netdissect_options *ndo,
register const u_char *bp, u_int length)
{
register const char *cp;
register int opcode;
u_int ui;
/* Print length */
ND_PRINT((ndo, " %d", length));
/* Print tftp request type */
if (length < 2)
goto trunc;
ND_TCHECK_16BITS(bp);
opcode = EXTRACT_16BITS(bp);
cp = tok2str(op2str, "tftp-#%d", opcode);
ND_PRINT((ndo, " %s", cp));
/* Bail if bogus opcode */
if (*cp == 't')
return;
bp += 2;
length -= 2;
switch (opcode) {
case RRQ:
case WRQ:
if (length == 0)
goto trunc;
ND_PRINT((ndo, " "));
/* Print filename */
ND_PRINT((ndo, "\""));
ui = fn_printztn(ndo, bp, length, ndo->ndo_snapend);
ND_PRINT((ndo, "\""));
if (ui == 0)
goto trunc;
bp += ui;
length -= ui;
/* Print the mode - RRQ and WRQ only */
if (length == 0)
goto trunc; /* no mode */
ND_PRINT((ndo, " "));
ui = fn_printztn(ndo, bp, length, ndo->ndo_snapend);
if (ui == 0)
goto trunc;
bp += ui;
length -= ui;
/* Print options, if any */
while (length != 0) {
ND_TCHECK(*bp);
if (*bp != '\0')
ND_PRINT((ndo, " "));
ui = fn_printztn(ndo, bp, length, ndo->ndo_snapend);
if (ui == 0)
goto trunc;
bp += ui;
length -= ui;
}
break;
case OACK:
/* Print options */
while (length != 0) {
ND_TCHECK(*bp);
if (*bp != '\0')
ND_PRINT((ndo, " "));
ui = fn_printztn(ndo, bp, length, ndo->ndo_snapend);
if (ui == 0)
goto trunc;
bp += ui;
length -= ui;
}
break;
case ACK:
case DATA:
if (length < 2)
goto trunc; /* no block number */
ND_TCHECK_16BITS(bp);
ND_PRINT((ndo, " block %d", EXTRACT_16BITS(bp)));
break;
case TFTP_ERROR:
/* Print error code string */
if (length < 2)
goto trunc; /* no error code */
ND_TCHECK_16BITS(bp);
ND_PRINT((ndo, " %s", tok2str(err2str, "tftp-err-#%d \"",
EXTRACT_16BITS(bp))));
bp += 2;
length -= 2;
/* Print error message string */
if (length == 0)
goto trunc; /* no error message */
ND_PRINT((ndo, " \""));
ui = fn_printztn(ndo, bp, length, ndo->ndo_snapend);
ND_PRINT((ndo, "\""));
if (ui == 0)
goto trunc;
break;
default:
/* We shouldn't get here */
ND_PRINT((ndo, "(unknown #%d)", opcode));
break;
}
return;
trunc:
ND_PRINT((ndo, "%s", tstr));
return;
}
|
