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