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