diff options
Diffstat (limited to 'print-tftp.c')
| -rw-r--r-- | print-tftp.c | 222 |
1 files changed, 222 insertions, 0 deletions
diff --git a/print-tftp.c b/print-tftp.c new file mode 100644 index 000000000000..69bc601fdda4 --- /dev/null +++ b/print-tftp.c @@ -0,0 +1,222 @@ +/* + * 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 */ + +struct tftphdr { + unsigned short th_opcode; /* packet type */ + union { + unsigned short tu_block; /* block # */ + unsigned short tu_code; /* error code */ + char tu_stuff[1]; /* request packet stuff */ + } th_u; + char th_data[1]; /* data or error string */ +}; + +#define th_block th_u.tu_block +#define th_code th_u.tu_code +#define th_stuff th_u.tu_stuff +#define th_msg th_data + +/* + * 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 struct tftphdr *tp; + register const char *cp; + register const u_char *p; + register int opcode; + u_int ui; + + tp = (const struct tftphdr *)bp; + + /* Print length */ + ND_PRINT((ndo, " %d", length)); + + /* Print tftp request type */ + if (length < 2) + goto trunc; + ND_TCHECK(tp->th_opcode); + opcode = EXTRACT_16BITS(&tp->th_opcode); + cp = tok2str(op2str, "tftp-#%d", opcode); + length -= 2; + ND_PRINT((ndo, " %s", cp)); + /* Bail if bogus opcode */ + if (*cp == 't') + return; + + switch (opcode) { + + case RRQ: + case WRQ: + p = (const u_char *)tp->th_stuff; + if (length == 0) + goto trunc; + ND_PRINT((ndo, " ")); + /* Print filename */ + ND_PRINT((ndo, "\"")); + ui = fn_printztn(ndo, p, length, ndo->ndo_snapend); + ND_PRINT((ndo, "\"")); + if (ui == 0) + goto trunc; + p += ui; + length -= ui; + + /* Print the mode - RRQ and WRQ only */ + if (length == 0) + goto trunc; /* no mode */ + ND_PRINT((ndo, " ")); + ui = fn_printztn(ndo, p, length, ndo->ndo_snapend); + if (ui == 0) + goto trunc; + p += ui; + length -= ui; + + /* Print options, if any */ + while (length != 0) { + ND_TCHECK(*p); + if (*p != '\0') + ND_PRINT((ndo, " ")); + ui = fn_printztn(ndo, p, length, ndo->ndo_snapend); + if (ui == 0) + goto trunc; + p += ui; + length -= ui; + } + break; + + case OACK: + p = (const u_char *)tp->th_stuff; + /* Print options */ + while (length != 0) { + ND_TCHECK(*p); + if (*p != '\0') + ND_PRINT((ndo, " ")); + ui = fn_printztn(ndo, p, length, ndo->ndo_snapend); + if (ui == 0) + goto trunc; + p += ui; + length -= ui; + } + break; + + case ACK: + case DATA: + if (length < 2) + goto trunc; /* no block number */ + ND_TCHECK(tp->th_block); + ND_PRINT((ndo, " block %d", EXTRACT_16BITS(&tp->th_block))); + break; + + case TFTP_ERROR: + /* Print error code string */ + if (length < 2) + goto trunc; /* no error code */ + ND_TCHECK(tp->th_code); + ND_PRINT((ndo, " %s", tok2str(err2str, "tftp-err-#%d \"", + EXTRACT_16BITS(&tp->th_code)))); + length -= 2; + /* Print error message string */ + if (length == 0) + goto trunc; /* no error message */ + ND_PRINT((ndo, " \"")); + ui = fn_printztn(ndo, (const u_char *)tp->th_data, 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; +} |