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 22 /* \summary: Trivial File Transfer Protocol (TFTP) printer */ 23 24 #include <sys/cdefs.h> 25 #ifndef lint 26 __RCSID("$NetBSD: print-tftp.c,v 1.9 2023/08/17 20:19:40 christos Exp $"); 27 #endif 28 29 #ifdef HAVE_CONFIG_H 30 #include <config.h> 31 #endif 32 33 #include "netdissect-stdinc.h" 34 35 #include "netdissect.h" 36 #include "extract.h" 37 38 /* 39 * Trivial File Transfer Protocol (IEN-133) 40 */ 41 42 /* 43 * Packet types. 44 */ 45 #define RRQ 01 /* read request */ 46 #define WRQ 02 /* write request */ 47 #define DATA 03 /* data packet */ 48 #define ACK 04 /* acknowledgement */ 49 #define TFTP_ERROR 05 /* error code */ 50 #define OACK 06 /* option acknowledgement */ 51 52 /* 53 * Error codes. 54 */ 55 #define EUNDEF 0 /* not defined */ 56 #define ENOTFOUND 1 /* file not found */ 57 #define EACCESS 2 /* access violation */ 58 #define ENOSPACE 3 /* disk full or allocation exceeded */ 59 #define EBADOP 4 /* illegal TFTP operation */ 60 #define EBADID 5 /* unknown transfer ID */ 61 #define EEXISTS 6 /* file already exists */ 62 #define ENOUSER 7 /* no such user */ 63 64 65 /* op code to string mapping */ 66 static const struct tok op2str[] = { 67 { RRQ, "RRQ" }, /* read request */ 68 { WRQ, "WRQ" }, /* write request */ 69 { DATA, "DATA" }, /* data packet */ 70 { ACK, "ACK" }, /* acknowledgement */ 71 { TFTP_ERROR, "ERROR" }, /* error code */ 72 { OACK, "OACK" }, /* option acknowledgement */ 73 { 0, NULL } 74 }; 75 76 /* error code to string mapping */ 77 static const struct tok err2str[] = { 78 { EUNDEF, "EUNDEF" }, /* not defined */ 79 { ENOTFOUND, "ENOTFOUND" }, /* file not found */ 80 { EACCESS, "EACCESS" }, /* access violation */ 81 { ENOSPACE, "ENOSPACE" }, /* disk full or allocation exceeded */ 82 { EBADOP, "EBADOP" }, /* illegal TFTP operation */ 83 { EBADID, "EBADID" }, /* unknown transfer ID */ 84 { EEXISTS, "EEXISTS" }, /* file already exists */ 85 { ENOUSER, "ENOUSER" }, /* no such user */ 86 { 0, NULL } 87 }; 88 89 /* 90 * Print trivial file transfer program requests 91 */ 92 void 93 tftp_print(netdissect_options *ndo, 94 const u_char *bp, u_int length) 95 { 96 const char *cp; 97 u_int opcode; 98 u_int ui; 99 100 ndo->ndo_protocol = "tftp"; 101 102 /* Print protocol */ 103 nd_print_protocol_caps(ndo); 104 /* Print length */ 105 ND_PRINT(", length %u", length); 106 107 /* Print tftp request type */ 108 if (length < 2) 109 goto trunc; 110 opcode = GET_BE_U_2(bp); 111 cp = tok2str(op2str, "tftp-#%u", opcode); 112 ND_PRINT(", %s", cp); 113 /* Bail if bogus opcode */ 114 if (*cp == 't') 115 return; 116 bp += 2; 117 length -= 2; 118 119 switch (opcode) { 120 121 case RRQ: 122 case WRQ: 123 if (length == 0) 124 goto trunc; 125 ND_PRINT(" "); 126 /* Print filename */ 127 ND_PRINT("\""); 128 ui = nd_printztn(ndo, bp, length, ndo->ndo_snapend); 129 ND_PRINT("\""); 130 if (ui == 0) 131 goto trunc; 132 bp += ui; 133 length -= ui; 134 135 /* Print the mode - RRQ and WRQ only */ 136 if (length == 0) 137 goto trunc; /* no mode */ 138 ND_PRINT(" "); 139 ui = nd_printztn(ndo, bp, length, ndo->ndo_snapend); 140 if (ui == 0) 141 goto trunc; 142 bp += ui; 143 length -= ui; 144 145 /* Print options, if any */ 146 while (length != 0) { 147 if (GET_U_1(bp) != '\0') 148 ND_PRINT(" "); 149 ui = nd_printztn(ndo, bp, length, ndo->ndo_snapend); 150 if (ui == 0) 151 goto trunc; 152 bp += ui; 153 length -= ui; 154 } 155 break; 156 157 case OACK: 158 /* Print options */ 159 while (length != 0) { 160 if (GET_U_1(bp) != '\0') 161 ND_PRINT(" "); 162 ui = nd_printztn(ndo, bp, length, ndo->ndo_snapend); 163 if (ui == 0) 164 goto trunc; 165 bp += ui; 166 length -= ui; 167 } 168 break; 169 170 case ACK: 171 case DATA: 172 if (length < 2) 173 goto trunc; /* no block number */ 174 ND_PRINT(" block %u", GET_BE_U_2(bp)); 175 break; 176 177 case TFTP_ERROR: 178 /* Print error code string */ 179 if (length < 2) 180 goto trunc; /* no error code */ 181 ND_PRINT(" %s", tok2str(err2str, "tftp-err-#%u \"", 182 GET_BE_U_2(bp))); 183 bp += 2; 184 length -= 2; 185 /* Print error message string */ 186 if (length == 0) 187 goto trunc; /* no error message */ 188 ND_PRINT(" \""); 189 ui = nd_printztn(ndo, bp, length, ndo->ndo_snapend); 190 ND_PRINT("\""); 191 if (ui == 0) 192 goto trunc; 193 break; 194 195 default: 196 /* We shouldn't get here */ 197 ND_PRINT("(unknown #%u)", opcode); 198 break; 199 } 200 return; 201 trunc: 202 nd_print_trunc(ndo); 203 } 204