1 /* 2 * Copyright (c) 1988-1990 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: 7 * 1. Source code distributions retain the above copyright 8 * notice and this paragraph in its entirety 9 * 2. Distributions including binary code include the above copyright 10 * notice and this paragraph in its entirety in the documentation 11 * or other materials provided with the distribution, and 12 * 3. Neither the name of the University nor the names of its contributors 13 * may be used to endorse or promote products derived from this software 14 * without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED 17 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF 18 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 19 * 20 * Format and print bootp packets. 21 * 22 * This file was copied from tcpdump-2.1.1 and modified. 23 * There is an e-mail list for tcpdump: <tcpdump@ee.lbl.gov> 24 * 25 * $FreeBSD$ 26 */ 27 28 #include <stdio.h> 29 30 #include <sys/param.h> 31 #include <sys/types.h> 32 #include <sys/socket.h> 33 34 #include <sys/time.h> /* for struct timeval in net/if.h */ 35 #include <net/if.h> 36 #include <netinet/in.h> 37 38 #include <string.h> 39 #include <ctype.h> 40 41 #include "bootp.h" 42 #include "bootptest.h" 43 44 /* These decode the vendor data. */ 45 static void rfc1048_print(u_char *bp, int length); 46 static void cmu_print(u_char *bp, int length); 47 static void other_print(u_char *bp, int length); 48 static void dump_hex(u_char *bp, int len); 49 50 /* 51 * Print bootp requests 52 */ 53 void 54 bootp_print(bp, length, sport, dport) 55 struct bootp *bp; 56 int length; 57 u_short sport, dport; 58 { 59 static char tstr[] = " [|bootp]"; 60 static unsigned char vm_cmu[4] = VM_CMU; 61 static unsigned char vm_rfc1048[4] = VM_RFC1048; 62 u_char *ep; 63 int vdlen; 64 65 #define TCHECK(var, l) if ((u_char *)&(var) > ep - l) goto trunc 66 67 /* Note funny sized packets */ 68 if (length != sizeof(struct bootp)) 69 (void) printf(" [len=%d]", length); 70 71 /* 'ep' points to the end of avaible data. */ 72 ep = (u_char *) snapend; 73 74 switch (bp->bp_op) { 75 76 case BOOTREQUEST: 77 /* Usually, a request goes from a client to a server */ 78 if (sport != IPPORT_BOOTPC || dport != IPPORT_BOOTPS) 79 printf(" (request)"); 80 break; 81 82 case BOOTREPLY: 83 /* Usually, a reply goes from a server to a client */ 84 if (sport != IPPORT_BOOTPS || dport != IPPORT_BOOTPC) 85 printf(" (reply)"); 86 break; 87 88 default: 89 printf(" bootp-#%d", bp->bp_op); 90 } 91 92 /* The usual hardware address type is 1 (10Mb Ethernet) */ 93 if (bp->bp_htype != 1) 94 printf(" htype:%d", bp->bp_htype); 95 96 /* The usual length for 10Mb Ethernet address is 6 bytes */ 97 if (bp->bp_hlen != 6) 98 printf(" hlen:%d", bp->bp_hlen); 99 100 /* Client's Hardware address */ 101 if (bp->bp_hlen) { 102 struct ether_header *eh; 103 char *e; 104 105 TCHECK(bp->bp_chaddr[0], 6); 106 eh = (struct ether_header *) packetp; 107 if (bp->bp_op == BOOTREQUEST) 108 e = (char *) ESRC(eh); 109 else if (bp->bp_op == BOOTREPLY) 110 e = (char *) EDST(eh); 111 else 112 e = NULL; 113 if (e == NULL || bcmp((char *) bp->bp_chaddr, e, 6)) 114 dump_hex(bp->bp_chaddr, bp->bp_hlen); 115 } 116 /* Only print interesting fields */ 117 if (bp->bp_hops) 118 printf(" hops:%d", bp->bp_hops); 119 120 if (bp->bp_xid) 121 printf(" xid:%ld", (long)ntohl(bp->bp_xid)); 122 123 if (bp->bp_secs) 124 printf(" secs:%d", ntohs(bp->bp_secs)); 125 126 /* Client's ip address */ 127 TCHECK(bp->bp_ciaddr, sizeof(bp->bp_ciaddr)); 128 if (bp->bp_ciaddr.s_addr) 129 printf(" C:%s", ipaddr_string(&bp->bp_ciaddr)); 130 131 /* 'your' ip address (bootp client) */ 132 TCHECK(bp->bp_yiaddr, sizeof(bp->bp_yiaddr)); 133 if (bp->bp_yiaddr.s_addr) 134 printf(" Y:%s", ipaddr_string(&bp->bp_yiaddr)); 135 136 /* Server's ip address */ 137 TCHECK(bp->bp_siaddr, sizeof(bp->bp_siaddr)); 138 if (bp->bp_siaddr.s_addr) 139 printf(" S:%s", ipaddr_string(&bp->bp_siaddr)); 140 141 /* Gateway's ip address */ 142 TCHECK(bp->bp_giaddr, sizeof(bp->bp_giaddr)); 143 if (bp->bp_giaddr.s_addr) 144 printf(" G:%s", ipaddr_string(&bp->bp_giaddr)); 145 146 TCHECK(bp->bp_sname[0], sizeof(bp->bp_sname)); 147 if (*bp->bp_sname) { 148 printf(" sname:"); 149 if (printfn(bp->bp_sname, ep)) { 150 fputs(tstr + 1, stdout); 151 return; 152 } 153 } 154 TCHECK(bp->bp_file[0], sizeof(bp->bp_file)); 155 if (*bp->bp_file) { 156 printf(" file:"); 157 if (printfn(bp->bp_file, ep)) { 158 fputs(tstr + 1, stdout); 159 return; 160 } 161 } 162 /* Don't try to decode the vendor buffer unless we're verbose */ 163 if (vflag <= 0) 164 return; 165 166 vdlen = sizeof(bp->bp_vend); 167 /* Vendor data can extend to the end of the packet. */ 168 if (vdlen < (ep - bp->bp_vend)) 169 vdlen = (ep - bp->bp_vend); 170 171 TCHECK(bp->bp_vend[0], vdlen); 172 printf(" vend"); 173 if (!bcmp(bp->bp_vend, vm_rfc1048, sizeof(u_int32))) 174 rfc1048_print(bp->bp_vend, vdlen); 175 else if (!bcmp(bp->bp_vend, vm_cmu, sizeof(u_int32))) 176 cmu_print(bp->bp_vend, vdlen); 177 else 178 other_print(bp->bp_vend, vdlen); 179 180 return; 181 trunc: 182 fputs(tstr, stdout); 183 #undef TCHECK 184 } 185 186 /* 187 * Option description data follows. 188 * These are described in: RFC-1048, RFC-1395, RFC-1497, RFC-1533 189 * 190 * The first char of each option string encodes the data format: 191 * ?: unknown 192 * a: ASCII 193 * b: byte (8-bit) 194 * i: inet address 195 * l: int32 196 * s: short (16-bit) 197 */ 198 char * 199 rfc1048_opts[] = { 200 /* Originally from RFC-1048: */ 201 "?PAD", /* 0: Padding - special, no data. */ 202 "iSM", /* 1: subnet mask (RFC950)*/ 203 "lTZ", /* 2: time offset, seconds from UTC */ 204 "iGW", /* 3: gateways (or routers) */ 205 "iTS", /* 4: time servers (RFC868) */ 206 "iINS", /* 5: IEN name servers (IEN116) */ 207 "iDNS", /* 6: domain name servers (RFC1035)(1034?) */ 208 "iLOG", /* 7: MIT log servers */ 209 "iCS", /* 8: cookie servers (RFC865) */ 210 "iLPR", /* 9: lpr server (RFC1179) */ 211 "iIPS", /* 10: impress servers (Imagen) */ 212 "iRLP", /* 11: resource location servers (RFC887) */ 213 "aHN", /* 12: host name (ASCII) */ 214 "sBFS", /* 13: boot file size (in 512 byte blocks) */ 215 216 /* Added by RFC-1395: */ 217 "aDUMP", /* 14: Merit Dump File */ 218 "aDNAM", /* 15: Domain Name (for DNS) */ 219 "iSWAP", /* 16: Swap Server */ 220 "aROOT", /* 17: Root Path */ 221 222 /* Added by RFC-1497: */ 223 "aEXTF", /* 18: Extensions Path (more options) */ 224 225 /* Added by RFC-1533: (many, many options...) */ 226 #if 1 /* These might not be worth recognizing by name. */ 227 228 /* IP Layer Parameters, per-host (RFC-1533, sect. 4) */ 229 "bIP-forward", /* 19: IP Forwarding flag */ 230 "bIP-srcroute", /* 20: IP Source Routing Enable flag */ 231 "iIP-filters", /* 21: IP Policy Filter (addr pairs) */ 232 "sIP-maxudp", /* 22: IP Max-UDP reassembly size */ 233 "bIP-ttlive", /* 23: IP Time to Live */ 234 "lIP-pmtuage", /* 24: IP Path MTU aging timeout */ 235 "sIP-pmtutab", /* 25: IP Path MTU plateau table */ 236 237 /* IP parameters, per-interface (RFC-1533, sect. 5) */ 238 "sIP-mtu-sz", /* 26: IP MTU size */ 239 "bIP-mtu-sl", /* 27: IP MTU all subnets local */ 240 "bIP-bcast1", /* 28: IP Broadcast Addr ones flag */ 241 "bIP-mask-d", /* 29: IP do mask discovery */ 242 "bIP-mask-s", /* 30: IP do mask supplier */ 243 "bIP-rt-dsc", /* 31: IP do router discovery */ 244 "iIP-rt-sa", /* 32: IP router solicitation addr */ 245 "iIP-routes", /* 33: IP static routes (dst,router) */ 246 247 /* Link Layer parameters, per-interface (RFC-1533, sect. 6) */ 248 "bLL-trailer", /* 34: do tralier encapsulation */ 249 "lLL-arp-tmo", /* 35: ARP cache timeout */ 250 "bLL-ether2", /* 36: Ethernet version 2 (IEEE 802.3) */ 251 252 /* TCP parameters (RFC-1533, sect. 7) */ 253 "bTCP-def-ttl", /* 37: default time to live */ 254 "lTCP-KA-tmo", /* 38: keepalive time interval */ 255 "bTCP-KA-junk", /* 39: keepalive sends extra junk */ 256 257 /* Application and Service Parameters (RFC-1533, sect. 8) */ 258 "aNISDOM", /* 40: NIS Domain (Sun YP) */ 259 "iNISSRV", /* 41: NIS Servers */ 260 "iNTPSRV", /* 42: NTP (time) Servers (RFC 1129) */ 261 "?VSINFO", /* 43: Vendor Specific Info (encapsulated) */ 262 "iNBiosNS", /* 44: NetBIOS Name Server (RFC-1001,1..2) */ 263 "iNBiosDD", /* 45: NetBIOS Datagram Dist. Server. */ 264 "bNBiosNT", /* 46: NetBIOS Note Type */ 265 "?NBiosS", /* 47: NetBIOS Scope */ 266 "iXW-FS", /* 48: X Window System Font Servers */ 267 "iXW-DM", /* 49: X Window System Display Managers */ 268 269 /* DHCP extensions (RFC-1533, sect. 9) */ 270 #endif 271 }; 272 #define KNOWN_OPTIONS (sizeof(rfc1048_opts) / sizeof(rfc1048_opts[0])) 273 274 static void 275 rfc1048_print(bp, length) 276 u_char *bp; 277 int length; 278 { 279 u_char tag; 280 u_char *ep; 281 int len; 282 u_int32 ul; 283 u_short us; 284 struct in_addr ia; 285 char *optstr; 286 287 printf("-rfc1395"); 288 289 /* Step over magic cookie */ 290 bp += sizeof(int32); 291 /* Setup end pointer */ 292 ep = bp + length; 293 while (bp < ep) { 294 tag = *bp++; 295 /* Check for tags with no data first. */ 296 if (tag == TAG_PAD) 297 continue; 298 if (tag == TAG_END) 299 return; 300 if (tag < KNOWN_OPTIONS) { 301 optstr = rfc1048_opts[tag]; 302 printf(" %s:", optstr + 1); 303 } else { 304 printf(" T%d:", tag); 305 optstr = "?"; 306 } 307 /* Now scan the length byte. */ 308 len = *bp++; 309 if (bp + len > ep) { 310 /* truncated option */ 311 printf(" |(%d>%td)", len, ep - bp); 312 return; 313 } 314 /* Print the option value(s). */ 315 switch (optstr[0]) { 316 317 case 'a': /* ASCII string */ 318 printfn(bp, bp + len); 319 bp += len; 320 len = 0; 321 break; 322 323 case 's': /* Word formats */ 324 while (len >= 2) { 325 bcopy((char *) bp, (char *) &us, 2); 326 printf("%d", ntohs(us)); 327 bp += 2; 328 len -= 2; 329 if (len) printf(","); 330 } 331 if (len) printf("(junk=%d)", len); 332 break; 333 334 case 'l': /* Long words */ 335 while (len >= 4) { 336 bcopy((char *) bp, (char *) &ul, 4); 337 printf("%ld", (long)ntohl(ul)); 338 bp += 4; 339 len -= 4; 340 if (len) printf(","); 341 } 342 if (len) printf("(junk=%d)", len); 343 break; 344 345 case 'i': /* INET addresses */ 346 while (len >= 4) { 347 bcopy((char *) bp, (char *) &ia, 4); 348 printf("%s", ipaddr_string(&ia)); 349 bp += 4; 350 len -= 4; 351 if (len) printf(","); 352 } 353 if (len) printf("(junk=%d)", len); 354 break; 355 356 case 'b': 357 default: 358 break; 359 360 } /* switch */ 361 362 /* Print as characters, if appropriate. */ 363 if (len) { 364 dump_hex(bp, len); 365 if (isascii(*bp) && isprint(*bp)) { 366 printf("("); 367 printfn(bp, bp + len); 368 printf(")"); 369 } 370 bp += len; 371 len = 0; 372 } 373 } /* while bp < ep */ 374 } 375 376 static void 377 cmu_print(bp, length) 378 u_char *bp; 379 int length; 380 { 381 struct cmu_vend *v; 382 383 printf("-cmu"); 384 385 v = (struct cmu_vend *) bp; 386 if (length < sizeof(*v)) { 387 printf(" |L=%d", length); 388 return; 389 } 390 391 /* Subnet mask */ 392 if (v->v_flags & VF_SMASK) { 393 printf(" SM:%s", ipaddr_string(&v->v_smask)); 394 } 395 /* Default gateway */ 396 if (v->v_dgate.s_addr) 397 printf(" GW:%s", ipaddr_string(&v->v_dgate)); 398 399 /* Domain name servers */ 400 if (v->v_dns1.s_addr) 401 printf(" DNS1:%s", ipaddr_string(&v->v_dns1)); 402 if (v->v_dns2.s_addr) 403 printf(" DNS2:%s", ipaddr_string(&v->v_dns2)); 404 405 /* IEN-116 name servers */ 406 if (v->v_ins1.s_addr) 407 printf(" INS1:%s", ipaddr_string(&v->v_ins1)); 408 if (v->v_ins2.s_addr) 409 printf(" INS2:%s", ipaddr_string(&v->v_ins2)); 410 411 /* Time servers */ 412 if (v->v_ts1.s_addr) 413 printf(" TS1:%s", ipaddr_string(&v->v_ts1)); 414 if (v->v_ts2.s_addr) 415 printf(" TS2:%s", ipaddr_string(&v->v_ts2)); 416 417 } 418 419 420 /* 421 * Print out arbitrary, unknown vendor data. 422 */ 423 424 static void 425 other_print(bp, length) 426 u_char *bp; 427 int length; 428 { 429 u_char *ep; /* end pointer */ 430 u_char *zp; /* points one past last non-zero byte */ 431 432 /* Setup end pointer */ 433 ep = bp + length; 434 435 /* Find the last non-zero byte. */ 436 for (zp = ep; zp > bp; zp--) { 437 if (zp[-1] != 0) 438 break; 439 } 440 441 /* Print the all-zero case in a compact representation. */ 442 if (zp == bp) { 443 printf("-all-zero"); 444 return; 445 } 446 printf("-unknown"); 447 448 /* Are there enough trailing zeros to make "00..." worthwhile? */ 449 if (zp + 2 > ep) 450 zp = ep; /* print them all normally */ 451 452 /* Now just print all the non-zero data. */ 453 while (bp < zp) { 454 printf(".%02X", *bp); 455 bp++; 456 } 457 458 if (zp < ep) 459 printf(".00..."); 460 461 return; 462 } 463 464 static void 465 dump_hex(bp, len) 466 u_char *bp; 467 int len; 468 { 469 while (len > 0) { 470 printf("%02X", *bp); 471 bp++; 472 len--; 473 if (len) printf("."); 474 } 475 } 476 477 /* 478 * Local Variables: 479 * tab-width: 4 480 * c-indent-level: 4 481 * c-argdecl-indent: 4 482 * c-continued-statement-offset: 4 483 * c-continued-brace-offset: -4 484 * c-label-offset: -4 485 * c-brace-offset: 0 486 * End: 487 */ 488