xref: /openbsd/usr.sbin/tcpdump/print-tftp.c (revision 73471bf0)
1 /*	$OpenBSD: print-tftp.c,v 1.14 2020/01/24 22:46:37 procter Exp $	*/
2 
3 /*
4  * Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996, 1997
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that: (1) source code distributions
9  * retain the above copyright notice and this paragraph in its entirety, (2)
10  * distributions including binary code include the above copyright notice and
11  * this paragraph in its entirety in the documentation or other materials
12  * provided with the distribution, and (3) all advertising materials mentioning
13  * features or use of this software display the following acknowledgement:
14  * ``This product includes software developed by the University of California,
15  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
16  * the University nor the names of its contributors may be used to endorse
17  * or promote products derived from this software without specific prior
18  * written permission.
19  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
20  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
21  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
22  *
23  * Format and print trivial file transfer protocol packets.
24  */
25 
26 #include <sys/time.h>
27 
28 #include <netinet/in.h>
29 
30 #ifdef SEGSIZE
31 #undef SEGSIZE					/* SINIX sucks */
32 #endif
33 #include <arpa/tftp.h>
34 
35 #include <ctype.h>
36 #include <stdio.h>
37 #include <string.h>
38 
39 #include "interface.h"
40 #include "addrtoname.h"
41 
42 /* op code to string mapping */
43 static struct tok op2str[] = {
44 	{ RRQ,		"RRQ" },	/* read request */
45 	{ WRQ,		"WRQ" },	/* write request */
46 	{ DATA,		"DATA" },	/* data packet */
47 	{ ACK,		"ACK" },	/* acknowledgement */
48 	{ ERROR,	"ERROR" },	/* error code */
49 	{ 0,		NULL }
50 };
51 
52 /* error code to string mapping */
53 static struct tok err2str[] = {
54 	{ EUNDEF,	"EUNDEF" },	/* not defined */
55 	{ ENOTFOUND,	"ENOTFOUND" },	/* file not found */
56 	{ EACCESS,	"EACCESS" },	/* access violation */
57 	{ ENOSPACE,	"ENOSPACE" },	/* disk full or allocation exceeded */
58 	{ EBADOP,	"EBADOP" },	/* illegal TFTP operation */
59 	{ EBADID,	"EBADID" },	/* unknown transfer ID */
60 	{ EEXISTS,	"EEXISTS" },	/* file already exists */
61 	{ ENOUSER,	"ENOUSER" },	/* no such user */
62 	{ 0,		NULL }
63 };
64 
65 /*
66  * Print trivial file transfer program requests
67  */
68 void
69 tftp_print(const u_char *bp, u_int length)
70 {
71 	const struct tftphdr *tp;
72 	const char *cp;
73 	const u_char *p;
74 	int opcode, i;
75 	static char tstr[] = " [|tftp]";
76 
77 	tp = (const struct tftphdr *)bp;
78 
79 	/* Print length */
80 	printf("%d", length);
81 
82 	/* Print tftp request type */
83 	TCHECK(tp->th_opcode);
84 	opcode = ntohs(tp->th_opcode);
85 	cp = tok2str(op2str, "tftp-#%d", opcode);
86 	printf(" %s", cp);
87 	/* Bail if bogus opcode */
88 	if (*cp == 't')
89 		return;
90 
91 	switch (opcode) {
92 
93 	case RRQ:
94 	case WRQ:
95 		/*
96 		 * XXX Not all arpa/tftp.h's specify th_stuff as any
97 		 * array; use address of th_block instead
98 		 */
99 #ifdef notdef
100 		p = (u_char *)tp->th_stuff;
101 #else
102 		p = (u_char *)&tp->th_block;
103 #endif
104 		printf(" \"");
105 		i = fn_print(p, snapend);
106 		putchar('"');
107 		if (i)
108 			goto trunc;
109 		break;
110 
111 	case ACK:
112 	case DATA:
113 		TCHECK(tp->th_block);
114 		printf(" block %d", ntohs(tp->th_block));
115 		break;
116 
117 	case ERROR:
118 		/* Print error code string */
119 		TCHECK(tp->th_code);
120 		printf(" %s ", tok2str(err2str, "tftp-err-#%d \"",
121 				       ntohs(tp->th_code)));
122 		/* Print error message string */
123 		putchar('"');
124 		i = fn_print((const u_char *)tp->th_data, snapend);
125 		putchar('"');
126 		if (i)
127 			goto trunc;
128 		break;
129 
130 	default:
131 		/* We shouldn't get here */
132 		printf("(unknown #%d)", opcode);
133 		break;
134 	}
135 	return;
136 trunc:
137 	printf("%s", tstr);
138 	return;
139 }
140