xref: /freebsd/contrib/tcpdump/print-tftp.c (revision d056fa046c6a91b90cd98165face0e42a33a5173)
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 1.37 2003/11/16 09:36:40 guy 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 #include <arpa/tftp.h>
39 
40 #include <stdio.h>
41 #include <string.h>
42 
43 #include "interface.h"
44 #include "addrtoname.h"
45 #include "extract.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 	{ ERROR,	"ERROR" },	/* error code */
54 	{ 0,		NULL }
55 };
56 
57 /* error code to string mapping */
58 static struct tok err2str[] = {
59 	{ EUNDEF,	"EUNDEF" },	/* not defined */
60 	{ ENOTFOUND,	"ENOTFOUND" },	/* file not found */
61 	{ EACCESS,	"EACCESS" },	/* access violation */
62 	{ ENOSPACE,	"ENOSPACE" },	/* disk full or allocation exceeded */
63 	{ EBADOP,	"EBADOP" },	/* illegal TFTP operation */
64 	{ EBADID,	"EBADID" },	/* unknown transfer ID */
65 	{ EEXISTS,	"EEXISTS" },	/* file already exists */
66 	{ ENOUSER,	"ENOUSER" },	/* no such user */
67 	{ 0,		NULL }
68 };
69 
70 /*
71  * Print trivial file transfer program requests
72  */
73 void
74 tftp_print(register const u_char *bp, u_int length)
75 {
76 	register const struct tftphdr *tp;
77 	register const char *cp;
78 	register const u_char *p;
79 	register int opcode, i;
80 	static char tstr[] = " [|tftp]";
81 
82 	tp = (const struct tftphdr *)bp;
83 
84 	/* Print length */
85 	printf(" %d", length);
86 
87 	/* Print tftp request type */
88 	TCHECK(tp->th_opcode);
89 	opcode = EXTRACT_16BITS(&tp->th_opcode);
90 	cp = tok2str(op2str, "tftp-#%d", opcode);
91 	printf(" %s", cp);
92 	/* Bail if bogus opcode */
93 	if (*cp == 't')
94 		return;
95 
96 	switch (opcode) {
97 
98 	case RRQ:
99 	case WRQ:
100 		/*
101 		 * XXX Not all arpa/tftp.h's specify th_stuff as any
102 		 * array; use address of th_block instead
103 		 */
104 #ifdef notdef
105 		p = (u_char *)tp->th_stuff;
106 #else
107 		p = (u_char *)&tp->th_block;
108 #endif
109 		fputs(" \"", stdout);
110 		i = fn_print(p, snapend);
111 		putchar('"');
112 
113 		/* Print the mode and any options */
114 		while ((p = (const u_char *)strchr((const char *)p, '\0')) != NULL) {
115 			if (length <= (u_int)(p - (const u_char *)&tp->th_block))
116 				break;
117 			p++;
118 			if (*p != '\0') {
119 				putchar(' ');
120 				fn_print(p, snapend);
121 			}
122 		}
123 
124 		if (i)
125 			goto trunc;
126 		break;
127 
128 	case ACK:
129 	case DATA:
130 		TCHECK(tp->th_block);
131 		printf(" block %d", EXTRACT_16BITS(&tp->th_block));
132 		break;
133 
134 	case ERROR:
135 		/* Print error code string */
136 		TCHECK(tp->th_code);
137 		printf(" %s ", tok2str(err2str, "tftp-err-#%d \"",
138 				       EXTRACT_16BITS(&tp->th_code)));
139 		/* Print error message string */
140 		i = fn_print((const u_char *)tp->th_data, snapend);
141 		putchar('"');
142 		if (i)
143 			goto trunc;
144 		break;
145 
146 	default:
147 		/* We shouldn't get here */
148 		printf("(unknown #%d)", opcode);
149 		break;
150 	}
151 	return;
152 trunc:
153 	fputs(tstr, stdout);
154 	return;
155 }
156