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 1.10 2024/09/02 16:15:33 christos Exp $"); 27 #endif 28 29 #include <config.h> 30 31 #include "netdissect-stdinc.h" 32 33 #include "netdissect.h" 34 #include "extract.h" 35 36 /* 37 * Trivial File Transfer Protocol (IEN-133) 38 */ 39 40 /* 41 * Packet types. 42 */ 43 #define RRQ 01 /* read request */ 44 #define WRQ 02 /* write request */ 45 #define DATA 03 /* data packet */ 46 #define ACK 04 /* acknowledgement */ 47 #define TFTP_ERROR 05 /* error code */ 48 #define OACK 06 /* option acknowledgement */ 49 50 /* 51 * Error codes. 52 */ 53 #define EUNDEF 0 /* not defined */ 54 #define ENOTFOUND 1 /* file not found */ 55 #define EACCESS 2 /* access violation */ 56 #define ENOSPACE 3 /* disk full or allocation exceeded */ 57 #define EBADOP 4 /* illegal TFTP operation */ 58 #define EBADID 5 /* unknown transfer ID */ 59 #define EEXISTS 6 /* file already exists */ 60 #define ENOUSER 7 /* no such user */ 61 62 63 /* op code to string mapping */ 64 static const struct tok op2str[] = { 65 { RRQ, "RRQ" }, /* read request */ 66 { WRQ, "WRQ" }, /* write request */ 67 { DATA, "DATA" }, /* data packet */ 68 { ACK, "ACK" }, /* acknowledgement */ 69 { TFTP_ERROR, "ERROR" }, /* error code */ 70 { OACK, "OACK" }, /* option acknowledgement */ 71 { 0, NULL } 72 }; 73 74 /* error code to string mapping */ 75 static const struct tok err2str[] = { 76 { EUNDEF, "EUNDEF" }, /* not defined */ 77 { ENOTFOUND, "ENOTFOUND" }, /* file not found */ 78 { EACCESS, "EACCESS" }, /* access violation */ 79 { ENOSPACE, "ENOSPACE" }, /* disk full or allocation exceeded */ 80 { EBADOP, "EBADOP" }, /* illegal TFTP operation */ 81 { EBADID, "EBADID" }, /* unknown transfer ID */ 82 { EEXISTS, "EEXISTS" }, /* file already exists */ 83 { ENOUSER, "ENOUSER" }, /* no such user */ 84 { 0, NULL } 85 }; 86 87 /* 88 * Print trivial file transfer program requests 89 */ 90 void 91 tftp_print(netdissect_options *ndo, 92 const u_char *bp, u_int length) 93 { 94 const char *cp; 95 u_int opcode; 96 u_int ui; 97 98 ndo->ndo_protocol = "tftp"; 99 100 /* Print protocol */ 101 nd_print_protocol_caps(ndo); 102 /* Print length */ 103 ND_PRINT(", length %u", length); 104 105 /* Print tftp request type */ 106 if (length < 2) 107 goto trunc; 108 opcode = GET_BE_U_2(bp); 109 cp = tok2str(op2str, "tftp-#%u", opcode); 110 ND_PRINT(", %s", cp); 111 /* Bail if bogus opcode */ 112 if (*cp == 't') 113 return; 114 bp += 2; 115 length -= 2; 116 117 switch (opcode) { 118 119 case RRQ: 120 case WRQ: 121 if (length == 0) 122 goto trunc; 123 ND_PRINT(" "); 124 /* Print filename */ 125 ND_PRINT("\""); 126 ui = nd_printztn(ndo, bp, length, ndo->ndo_snapend); 127 ND_PRINT("\""); 128 if (ui == 0) 129 goto trunc; 130 bp += ui; 131 length -= ui; 132 133 /* Print the mode - RRQ and WRQ only */ 134 if (length == 0) 135 goto trunc; /* no mode */ 136 ND_PRINT(" "); 137 ui = nd_printztn(ndo, bp, length, ndo->ndo_snapend); 138 if (ui == 0) 139 goto trunc; 140 bp += ui; 141 length -= ui; 142 143 /* Print options, if any */ 144 while (length != 0) { 145 if (GET_U_1(bp) != '\0') 146 ND_PRINT(" "); 147 ui = nd_printztn(ndo, bp, length, ndo->ndo_snapend); 148 if (ui == 0) 149 goto trunc; 150 bp += ui; 151 length -= ui; 152 } 153 break; 154 155 case OACK: 156 /* Print options */ 157 while (length != 0) { 158 if (GET_U_1(bp) != '\0') 159 ND_PRINT(" "); 160 ui = nd_printztn(ndo, bp, length, ndo->ndo_snapend); 161 if (ui == 0) 162 goto trunc; 163 bp += ui; 164 length -= ui; 165 } 166 break; 167 168 case ACK: 169 case DATA: 170 if (length < 2) 171 goto trunc; /* no block number */ 172 ND_PRINT(" block %u", GET_BE_U_2(bp)); 173 break; 174 175 case TFTP_ERROR: 176 /* Print error code string */ 177 if (length < 2) 178 goto trunc; /* no error code */ 179 ND_PRINT(" %s", tok2str(err2str, "tftp-err-#%u \"", 180 GET_BE_U_2(bp))); 181 bp += 2; 182 length -= 2; 183 /* Print error message string */ 184 if (length == 0) 185 goto trunc; /* no error message */ 186 ND_PRINT(" \""); 187 ui = nd_printztn(ndo, bp, length, ndo->ndo_snapend); 188 ND_PRINT("\""); 189 if (ui == 0) 190 goto trunc; 191 break; 192 193 default: 194 /* We shouldn't get here */ 195 ND_PRINT("(unknown #%u)", opcode); 196 break; 197 } 198 return; 199 trunc: 200 nd_print_trunc(ndo); 201 } 202