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