xref: /freebsd/contrib/tcpdump/print-tftp.c (revision 2f02600abfddfc4e9f20dd384a2e729b451e16bd)
1 /*
2  * Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996, 1997
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that: (1) source code distributions
7  * retain the above copyright notice and this paragraph in its entirety, (2)
8  * distributions including binary code include the above copyright notice and
9  * this paragraph in its entirety in the documentation or other materials
10  * provided with the distribution, and (3) all advertising materials mentioning
11  * features or use of this software display the following acknowledgement:
12  * ``This product includes software developed by the University of California,
13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14  * the University nor the names of its contributors may be used to endorse
15  * or promote products derived from this software without specific prior
16  * written permission.
17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20  *
21  * Format and print trivial file transfer protocol packets.
22  */
23 
24 #ifndef lint
25 static const char rcsid[] _U_ =
26     "@(#) $Header: /tcpdump/master/tcpdump/print-tftp.c,v 1.39 2008-04-11 16:47:38 gianluca Exp $ (LBL)";
27 #endif
28 
29 #ifdef HAVE_CONFIG_H
30 #include "config.h"
31 #endif
32 
33 #include <tcpdump-stdinc.h>
34 
35 #ifdef SEGSIZE
36 #undef SEGSIZE					/* SINIX sucks */
37 #endif
38 
39 #include <stdio.h>
40 #include <string.h>
41 
42 #include "interface.h"
43 #include "addrtoname.h"
44 #include "extract.h"
45 #include "tftp.h"
46 
47 /* op code to string mapping */
48 static struct tok op2str[] = {
49 	{ RRQ,		"RRQ" },	/* read request */
50 	{ WRQ,		"WRQ" },	/* write request */
51 	{ DATA,		"DATA" },	/* data packet */
52 	{ ACK,		"ACK" },	/* acknowledgement */
53 	{ TFTP_ERROR,	"ERROR" },	/* error code */
54 	{ OACK,		"OACK" },	/* option acknowledgement */
55 	{ 0,		NULL }
56 };
57 
58 /* error code to string mapping */
59 static struct tok err2str[] = {
60 	{ EUNDEF,	"EUNDEF" },	/* not defined */
61 	{ ENOTFOUND,	"ENOTFOUND" },	/* file not found */
62 	{ EACCESS,	"EACCESS" },	/* access violation */
63 	{ ENOSPACE,	"ENOSPACE" },	/* disk full or allocation exceeded */
64 	{ EBADOP,	"EBADOP" },	/* illegal TFTP operation */
65 	{ EBADID,	"EBADID" },	/* unknown transfer ID */
66 	{ EEXISTS,	"EEXISTS" },	/* file already exists */
67 	{ ENOUSER,	"ENOUSER" },	/* no such user */
68 	{ 0,		NULL }
69 };
70 
71 /*
72  * Print trivial file transfer program requests
73  */
74 void
75 tftp_print(register const u_char *bp, u_int length)
76 {
77 	register const struct tftphdr *tp;
78 	register const char *cp;
79 	register const u_char *p;
80 	register int opcode, i;
81 	static char tstr[] = " [|tftp]";
82 
83 	tp = (const struct tftphdr *)bp;
84 
85 	/* Print length */
86 	printf(" %d", length);
87 
88 	/* Print tftp request type */
89 	TCHECK(tp->th_opcode);
90 	opcode = EXTRACT_16BITS(&tp->th_opcode);
91 	cp = tok2str(op2str, "tftp-#%d", opcode);
92 	printf(" %s", cp);
93 	/* Bail if bogus opcode */
94 	if (*cp == 't')
95 		return;
96 
97 	switch (opcode) {
98 
99 	case RRQ:
100 	case WRQ:
101 	case OACK:
102 		p = (u_char *)tp->th_stuff;
103 		putchar(' ');
104 		/* Print filename or first option */
105 		if (opcode != OACK)
106 			putchar('"');
107 		i = fn_print(p, snapend);
108 		if (opcode != OACK)
109 			putchar('"');
110 
111 		/* Print the mode (RRQ and WRQ only) and any options */
112 		while ((p = (const u_char *)strchr((const char *)p, '\0')) != NULL) {
113 			if (length <= (u_int)(p - (const u_char *)&tp->th_block))
114 				break;
115 			p++;
116 			if (*p != '\0') {
117 				putchar(' ');
118 				fn_print(p, snapend);
119 			}
120 		}
121 
122 		if (i)
123 			goto trunc;
124 		break;
125 
126 	case ACK:
127 	case DATA:
128 		TCHECK(tp->th_block);
129 		printf(" block %d", EXTRACT_16BITS(&tp->th_block));
130 		break;
131 
132 	case TFTP_ERROR:
133 		/* Print error code string */
134 		TCHECK(tp->th_code);
135 		printf(" %s \"", tok2str(err2str, "tftp-err-#%d \"",
136 				       EXTRACT_16BITS(&tp->th_code)));
137 		/* Print error message string */
138 		i = fn_print((const u_char *)tp->th_data, snapend);
139 		putchar('"');
140 		if (i)
141 			goto trunc;
142 		break;
143 
144 	default:
145 		/* We shouldn't get here */
146 		printf("(unknown #%d)", opcode);
147 		break;
148 	}
149 	return;
150 trunc:
151 	fputs(tstr, stdout);
152 	return;
153 }
154