1 /* $NetBSD: pf_osfp.c,v 1.10 2010/04/12 13:57:38 ahoka Exp $ */ 2 /* $OpenBSD: pf_osfp.c,v 1.12 2006/12/13 18:14:10 itojun Exp $ */ 3 4 /* 5 * Copyright (c) 2003 Mike Frantzen <frantzen@w4g.org> 6 * 7 * Permission to use, copy, modify, and distribute this software for any 8 * purpose with or without fee is hereby granted, provided that the above 9 * copyright notice and this permission notice appear in all copies. 10 * 11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18 * 19 */ 20 21 #include <sys/cdefs.h> 22 __KERNEL_RCSID(0, "$NetBSD: pf_osfp.c,v 1.10 2010/04/12 13:57:38 ahoka Exp $"); 23 24 #ifdef _KERNEL_OPT 25 #include "opt_inet.h" 26 #endif 27 28 #include <sys/param.h> 29 #include <sys/socket.h> 30 #ifdef _KERNEL 31 # include <sys/systm.h> 32 #endif /* _KERNEL */ 33 #include <sys/mbuf.h> 34 35 #include <netinet/in.h> 36 #include <netinet/in_systm.h> 37 #include <netinet/ip.h> 38 #include <netinet/tcp.h> 39 40 #include <net/if.h> 41 #include <net/pfvar.h> 42 43 #include <netinet/ip6.h> 44 #ifdef _KERNEL 45 #include <netinet6/in6_var.h> 46 #endif 47 48 49 #ifdef _KERNEL 50 # define DPFPRINTF(format, x...) \ 51 if (pf_status.debug >= PF_DEBUG_NOISY) \ 52 printf(format , ##x) 53 typedef struct pool pool_t; 54 55 #else 56 /* Userland equivalents so we can lend code to tcpdump et al. */ 57 58 # include <arpa/inet.h> 59 # include <errno.h> 60 # include <stdio.h> 61 # include <stdlib.h> 62 # include <string.h> 63 # include <netdb.h> 64 # define pool_t int 65 # define pool_get(pool, flags) malloc(*(pool)) 66 # define pool_put(pool, item) free(item) 67 # define pool_init(pool, size, a, ao, f, m, p) (*(pool)) = (size) 68 69 # ifdef PFDEBUG 70 # include <sys/stdarg.h> 71 # define DPFPRINTF(format, x...) fprintf(stderr, format , ##x) 72 # else 73 # define DPFPRINTF(format, x...) ((void)0) 74 # endif /* PFDEBUG */ 75 #endif /* _KERNEL */ 76 77 78 SLIST_HEAD(pf_osfp_list, pf_os_fingerprint) pf_osfp_list; 79 pool_t pf_osfp_entry_pl; 80 pool_t pf_osfp_pl; 81 82 struct pf_os_fingerprint *pf_osfp_find(struct pf_osfp_list *, 83 struct pf_os_fingerprint *, u_int8_t); 84 struct pf_os_fingerprint *pf_osfp_find_exact(struct pf_osfp_list *, 85 struct pf_os_fingerprint *); 86 void pf_osfp_insert(struct pf_osfp_list *, 87 struct pf_os_fingerprint *); 88 89 90 #ifdef _KERNEL 91 /* 92 * Passively fingerprint the OS of the host (IPv4 TCP SYN packets only) 93 * Returns the list of possible OSes. 94 */ 95 struct pf_osfp_enlist * 96 pf_osfp_fingerprint(struct pf_pdesc *pd, struct mbuf *m, int off, 97 const struct tcphdr *tcp) 98 { 99 struct ip *ip; 100 struct ip6_hdr *ip6; 101 char hdr[60]; 102 103 if ((pd->af != PF_INET && pd->af != PF_INET6) || 104 pd->proto != IPPROTO_TCP || (tcp->th_off << 2) < sizeof(*tcp)) 105 return (NULL); 106 107 if (pd->af == PF_INET) { 108 ip = mtod(m, struct ip *); 109 ip6 = (struct ip6_hdr *)NULL; 110 } else { 111 ip = (struct ip *)NULL; 112 ip6 = mtod(m, struct ip6_hdr *); 113 } 114 if (!pf_pull_hdr(m, off, hdr, tcp->th_off << 2, NULL, NULL, 115 pd->af)) return (NULL); 116 117 return (pf_osfp_fingerprint_hdr(ip, ip6, (struct tcphdr *)hdr)); 118 } 119 #endif /* _KERNEL */ 120 121 struct pf_osfp_enlist * 122 pf_osfp_fingerprint_hdr(const struct ip *ip, const struct ip6_hdr *ip6, const struct tcphdr *tcp) 123 { 124 struct pf_os_fingerprint fp, *fpresult; 125 int cnt, optlen = 0; 126 const u_int8_t *optp; 127 #ifdef _KERNEL 128 char srcname[128]; 129 #else 130 char srcname[NI_MAXHOST]; 131 #endif 132 133 if ((tcp->th_flags & (TH_SYN|TH_ACK)) != TH_SYN) 134 return (NULL); 135 if (ip) { 136 if ((ip->ip_off & htons(IP_OFFMASK)) != 0) 137 return (NULL); 138 } 139 140 memset(&fp, 0, sizeof(fp)); 141 142 if (ip) { 143 #ifndef _KERNEL 144 struct sockaddr_in sin; 145 #endif 146 147 fp.fp_psize = ntohs(ip->ip_len); 148 fp.fp_ttl = ip->ip_ttl; 149 if (ip->ip_off & htons(IP_DF)) 150 fp.fp_flags |= PF_OSFP_DF; 151 #ifdef _KERNEL 152 strlcpy(srcname, inet_ntoa(ip->ip_src), sizeof(srcname)); 153 #else 154 memset(&sin, 0, sizeof(sin)); 155 sin.sin_family = AF_INET; 156 sin.sin_len = sizeof(struct sockaddr_in); 157 sin.sin_addr = ip->ip_src; 158 (void)getnameinfo((struct sockaddr *)&sin, 159 sizeof(struct sockaddr_in), srcname, sizeof(srcname), 160 NULL, 0, NI_NUMERICHOST); 161 #endif 162 } 163 #ifdef INET6 164 else if (ip6) { 165 #ifndef _KERNEL 166 struct sockaddr_in6 sin6; 167 #endif 168 169 /* jumbo payload? */ 170 fp.fp_psize = sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen); 171 fp.fp_ttl = ip6->ip6_hlim; 172 fp.fp_flags |= PF_OSFP_DF; 173 fp.fp_flags |= PF_OSFP_INET6; 174 #ifdef _KERNEL 175 strlcpy(srcname, 176 ip6_sprintf((const struct in6_addr *)&ip6->ip6_src), 177 sizeof(srcname)); 178 #else 179 memset(&sin6, 0, sizeof(sin6)); 180 sin6.sin6_family = AF_INET6; 181 sin6.sin6_len = sizeof(struct sockaddr_in6); 182 sin6.sin6_addr = ip6->ip6_src; 183 (void)getnameinfo((struct sockaddr *)&sin6, 184 sizeof(struct sockaddr_in6), srcname, sizeof(srcname), 185 NULL, 0, NI_NUMERICHOST); 186 #endif 187 } 188 #endif 189 else 190 return (NULL); 191 fp.fp_wsize = ntohs(tcp->th_win); 192 193 194 cnt = (tcp->th_off << 2) - sizeof(*tcp); 195 optp = (const u_int8_t *)((const char *)tcp + sizeof(*tcp)); 196 for (; cnt > 0; cnt -= optlen, optp += optlen) { 197 if (*optp == TCPOPT_EOL) 198 break; 199 200 fp.fp_optcnt++; 201 if (*optp == TCPOPT_NOP) { 202 fp.fp_tcpopts = (fp.fp_tcpopts << PF_OSFP_TCPOPT_BITS) | 203 PF_OSFP_TCPOPT_NOP; 204 optlen = 1; 205 } else { 206 if (cnt < 2) 207 return (NULL); 208 optlen = optp[1]; 209 if (optlen > cnt || optlen < 2) 210 return (NULL); 211 switch (*optp) { 212 case TCPOPT_MAXSEG: 213 if (optlen >= TCPOLEN_MAXSEG) 214 memcpy(&fp.fp_mss, &optp[2], 215 sizeof(fp.fp_mss)); 216 fp.fp_tcpopts = (fp.fp_tcpopts << 217 PF_OSFP_TCPOPT_BITS) | PF_OSFP_TCPOPT_MSS; 218 NTOHS(fp.fp_mss); 219 break; 220 case TCPOPT_WINDOW: 221 if (optlen >= TCPOLEN_WINDOW) 222 memcpy(&fp.fp_wscale, &optp[2], 223 sizeof(fp.fp_wscale)); 224 NTOHS(fp.fp_wscale); 225 fp.fp_tcpopts = (fp.fp_tcpopts << 226 PF_OSFP_TCPOPT_BITS) | 227 PF_OSFP_TCPOPT_WSCALE; 228 break; 229 case TCPOPT_SACK_PERMITTED: 230 fp.fp_tcpopts = (fp.fp_tcpopts << 231 PF_OSFP_TCPOPT_BITS) | PF_OSFP_TCPOPT_SACK; 232 break; 233 case TCPOPT_TIMESTAMP: 234 if (optlen >= TCPOLEN_TIMESTAMP) { 235 u_int32_t ts; 236 memcpy(&ts, &optp[2], sizeof(ts)); 237 if (ts == 0) 238 fp.fp_flags |= PF_OSFP_TS0; 239 240 } 241 fp.fp_tcpopts = (fp.fp_tcpopts << 242 PF_OSFP_TCPOPT_BITS) | PF_OSFP_TCPOPT_TS; 243 break; 244 default: 245 return (NULL); 246 } 247 } 248 optlen = MAX(optlen, 1); /* paranoia */ 249 } 250 251 DPFPRINTF("fingerprinted %s:%d %d:%d:%d:%d:%llx (%d) " 252 "(TS=%s,M=%s%d,W=%s%d)\n", 253 srcname, ntohs(tcp->th_sport), 254 fp.fp_wsize, fp.fp_ttl, (fp.fp_flags & PF_OSFP_DF) != 0, 255 fp.fp_psize, (long long int)fp.fp_tcpopts, fp.fp_optcnt, 256 (fp.fp_flags & PF_OSFP_TS0) ? "0" : "", 257 (fp.fp_flags & PF_OSFP_MSS_MOD) ? "%" : 258 (fp.fp_flags & PF_OSFP_MSS_DC) ? "*" : "", 259 fp.fp_mss, 260 (fp.fp_flags & PF_OSFP_WSCALE_MOD) ? "%" : 261 (fp.fp_flags & PF_OSFP_WSCALE_DC) ? "*" : "", 262 fp.fp_wscale); 263 264 if ((fpresult = pf_osfp_find(&pf_osfp_list, &fp, 265 PF_OSFP_MAXTTL_OFFSET))) 266 return (&fpresult->fp_oses); 267 return (NULL); 268 } 269 270 /* Match a fingerprint ID against a list of OSes */ 271 int 272 pf_osfp_match(struct pf_osfp_enlist *list, pf_osfp_t os) 273 { 274 struct pf_osfp_entry *entry; 275 int os_class, os_version, os_subtype; 276 int en_class, en_version, en_subtype; 277 278 if (os == PF_OSFP_ANY) 279 return (1); 280 if (list == NULL) { 281 DPFPRINTF("osfp no match against %x\n", os); 282 return (os == PF_OSFP_UNKNOWN); 283 } 284 PF_OSFP_UNPACK(os, os_class, os_version, os_subtype); 285 SLIST_FOREACH(entry, list, fp_entry) { 286 PF_OSFP_UNPACK(entry->fp_os, en_class, en_version, en_subtype); 287 if ((os_class == PF_OSFP_ANY || en_class == os_class) && 288 (os_version == PF_OSFP_ANY || en_version == os_version) && 289 (os_subtype == PF_OSFP_ANY || en_subtype == os_subtype)) { 290 DPFPRINTF("osfp matched %s %s %s %x==%x\n", 291 entry->fp_class_nm, entry->fp_version_nm, 292 entry->fp_subtype_nm, os, entry->fp_os); 293 return (1); 294 } 295 } 296 DPFPRINTF("fingerprint 0x%x didn't match\n", os); 297 return (0); 298 } 299 300 /* Initialize the OS fingerprint system */ 301 void 302 pf_osfp_initialize(void) 303 { 304 #ifdef __NetBSD__ 305 pool_init(&pf_osfp_entry_pl, sizeof(struct pf_osfp_entry), 0, 0, 0, 306 "pfosfpen", &pool_allocator_nointr, IPL_NONE); 307 pool_init(&pf_osfp_pl, sizeof(struct pf_os_fingerprint), 0, 0, 0, 308 "pfosfp", &pool_allocator_nointr, IPL_NONE); 309 #else 310 pool_init(&pf_osfp_entry_pl, sizeof(struct pf_osfp_entry), 0, 0, 0, 311 "pfosfpen", &pool_allocator_nointr); 312 pool_init(&pf_osfp_pl, sizeof(struct pf_os_fingerprint), 0, 0, 0, 313 "pfosfp", &pool_allocator_nointr); 314 #endif /* !__NetBSD__ */ 315 SLIST_INIT(&pf_osfp_list); 316 } 317 318 #ifdef _MODULE 319 void 320 pf_osfp_destroy(void) 321 { 322 pf_osfp_flush(); 323 324 pool_destroy(&pf_osfp_pl); 325 pool_destroy(&pf_osfp_entry_pl); 326 } 327 #endif /* _MODULE */ 328 329 /* Flush the fingerprint list */ 330 void 331 pf_osfp_flush(void) 332 { 333 struct pf_os_fingerprint *fp; 334 struct pf_osfp_entry *entry; 335 336 while ((fp = SLIST_FIRST(&pf_osfp_list))) { 337 SLIST_REMOVE_HEAD(&pf_osfp_list, fp_next); 338 while ((entry = SLIST_FIRST(&fp->fp_oses))) { 339 SLIST_REMOVE_HEAD(&fp->fp_oses, fp_entry); 340 pool_put(&pf_osfp_entry_pl, entry); 341 } 342 pool_put(&pf_osfp_pl, fp); 343 } 344 } 345 346 347 /* Add a fingerprint */ 348 int 349 pf_osfp_add(struct pf_osfp_ioctl *fpioc) 350 { 351 struct pf_os_fingerprint *fp, fpadd; 352 struct pf_osfp_entry *entry; 353 354 memset(&fpadd, 0, sizeof(fpadd)); 355 fpadd.fp_tcpopts = fpioc->fp_tcpopts; 356 fpadd.fp_wsize = fpioc->fp_wsize; 357 fpadd.fp_psize = fpioc->fp_psize; 358 fpadd.fp_mss = fpioc->fp_mss; 359 fpadd.fp_flags = fpioc->fp_flags; 360 fpadd.fp_optcnt = fpioc->fp_optcnt; 361 fpadd.fp_wscale = fpioc->fp_wscale; 362 fpadd.fp_ttl = fpioc->fp_ttl; 363 364 DPFPRINTF("adding osfp %s %s %s = %s%d:%d:%d:%s%d:0x%llx %d " 365 "(TS=%s,M=%s%d,W=%s%d) %x\n", 366 fpioc->fp_os.fp_class_nm, fpioc->fp_os.fp_version_nm, 367 fpioc->fp_os.fp_subtype_nm, 368 (fpadd.fp_flags & PF_OSFP_WSIZE_MOD) ? "%" : 369 (fpadd.fp_flags & PF_OSFP_WSIZE_MSS) ? "S" : 370 (fpadd.fp_flags & PF_OSFP_WSIZE_MTU) ? "T" : 371 (fpadd.fp_flags & PF_OSFP_WSIZE_DC) ? "*" : "", 372 fpadd.fp_wsize, 373 fpadd.fp_ttl, 374 (fpadd.fp_flags & PF_OSFP_DF) ? 1 : 0, 375 (fpadd.fp_flags & PF_OSFP_PSIZE_MOD) ? "%" : 376 (fpadd.fp_flags & PF_OSFP_PSIZE_DC) ? "*" : "", 377 fpadd.fp_psize, 378 (long long int)fpadd.fp_tcpopts, fpadd.fp_optcnt, 379 (fpadd.fp_flags & PF_OSFP_TS0) ? "0" : "", 380 (fpadd.fp_flags & PF_OSFP_MSS_MOD) ? "%" : 381 (fpadd.fp_flags & PF_OSFP_MSS_DC) ? "*" : "", 382 fpadd.fp_mss, 383 (fpadd.fp_flags & PF_OSFP_WSCALE_MOD) ? "%" : 384 (fpadd.fp_flags & PF_OSFP_WSCALE_DC) ? "*" : "", 385 fpadd.fp_wscale, 386 fpioc->fp_os.fp_os); 387 388 389 if ((fp = pf_osfp_find_exact(&pf_osfp_list, &fpadd))) { 390 SLIST_FOREACH(entry, &fp->fp_oses, fp_entry) { 391 if (PF_OSFP_ENTRY_EQ(entry, &fpioc->fp_os)) 392 return (EEXIST); 393 } 394 if ((entry = pool_get(&pf_osfp_entry_pl, PR_NOWAIT)) == NULL) 395 return (ENOMEM); 396 } else { 397 if ((fp = pool_get(&pf_osfp_pl, PR_NOWAIT)) == NULL) 398 return (ENOMEM); 399 memset(fp, 0, sizeof(*fp)); 400 fp->fp_tcpopts = fpioc->fp_tcpopts; 401 fp->fp_wsize = fpioc->fp_wsize; 402 fp->fp_psize = fpioc->fp_psize; 403 fp->fp_mss = fpioc->fp_mss; 404 fp->fp_flags = fpioc->fp_flags; 405 fp->fp_optcnt = fpioc->fp_optcnt; 406 fp->fp_wscale = fpioc->fp_wscale; 407 fp->fp_ttl = fpioc->fp_ttl; 408 SLIST_INIT(&fp->fp_oses); 409 if ((entry = pool_get(&pf_osfp_entry_pl, PR_NOWAIT)) == NULL) { 410 pool_put(&pf_osfp_pl, fp); 411 return (ENOMEM); 412 } 413 pf_osfp_insert(&pf_osfp_list, fp); 414 } 415 memcpy(entry, &fpioc->fp_os, sizeof(*entry)); 416 417 /* Make sure the strings are NUL terminated */ 418 entry->fp_class_nm[sizeof(entry->fp_class_nm)-1] = '\0'; 419 entry->fp_version_nm[sizeof(entry->fp_version_nm)-1] = '\0'; 420 entry->fp_subtype_nm[sizeof(entry->fp_subtype_nm)-1] = '\0'; 421 422 SLIST_INSERT_HEAD(&fp->fp_oses, entry, fp_entry); 423 424 #ifdef PFDEBUG 425 if ((fp = pf_osfp_validate())) 426 printf("Invalid fingerprint list\n"); 427 #endif /* PFDEBUG */ 428 return (0); 429 } 430 431 432 /* Find a fingerprint in the list */ 433 struct pf_os_fingerprint * 434 pf_osfp_find(struct pf_osfp_list *list, struct pf_os_fingerprint *find, 435 u_int8_t ttldiff) 436 { 437 struct pf_os_fingerprint *f; 438 439 #define MATCH_INT(_MOD, _DC, _field) \ 440 if ((f->fp_flags & _DC) == 0) { \ 441 if ((f->fp_flags & _MOD) == 0) { \ 442 if (f->_field != find->_field) \ 443 continue; \ 444 } else { \ 445 if (f->_field == 0 || find->_field % f->_field) \ 446 continue; \ 447 } \ 448 } 449 450 SLIST_FOREACH(f, list, fp_next) { 451 if (f->fp_tcpopts != find->fp_tcpopts || 452 f->fp_optcnt != find->fp_optcnt || 453 f->fp_ttl < find->fp_ttl || 454 f->fp_ttl - find->fp_ttl > ttldiff || 455 (f->fp_flags & (PF_OSFP_DF|PF_OSFP_TS0)) != 456 (find->fp_flags & (PF_OSFP_DF|PF_OSFP_TS0))) 457 continue; 458 459 MATCH_INT(PF_OSFP_PSIZE_MOD, PF_OSFP_PSIZE_DC, fp_psize) 460 MATCH_INT(PF_OSFP_MSS_MOD, PF_OSFP_MSS_DC, fp_mss) 461 MATCH_INT(PF_OSFP_WSCALE_MOD, PF_OSFP_WSCALE_DC, fp_wscale) 462 if ((f->fp_flags & PF_OSFP_WSIZE_DC) == 0) { 463 if (f->fp_flags & PF_OSFP_WSIZE_MSS) { 464 if (find->fp_mss == 0) 465 continue; 466 467 /* Some "smart" NAT devices and DSL routers will tweak the MSS size and 468 * will set it to whatever is suitable for the link type. 469 */ 470 #define SMART_MSS 1460 471 if ((find->fp_wsize % find->fp_mss || 472 find->fp_wsize / find->fp_mss != 473 f->fp_wsize) && 474 (find->fp_wsize % SMART_MSS || 475 find->fp_wsize / SMART_MSS != 476 f->fp_wsize)) 477 continue; 478 } else if (f->fp_flags & PF_OSFP_WSIZE_MTU) { 479 if (find->fp_mss == 0) 480 continue; 481 482 #define MTUOFF (sizeof(struct ip) + sizeof(struct tcphdr)) 483 #define SMART_MTU (SMART_MSS + MTUOFF) 484 if ((find->fp_wsize % (find->fp_mss + MTUOFF) || 485 find->fp_wsize / (find->fp_mss + MTUOFF) != 486 f->fp_wsize) && 487 (find->fp_wsize % SMART_MTU || 488 find->fp_wsize / SMART_MTU != 489 f->fp_wsize)) 490 continue; 491 } else if (f->fp_flags & PF_OSFP_WSIZE_MOD) { 492 if (f->fp_wsize == 0 || find->fp_wsize % 493 f->fp_wsize) 494 continue; 495 } else { 496 if (f->fp_wsize != find->fp_wsize) 497 continue; 498 } 499 } 500 return (f); 501 } 502 503 return (NULL); 504 } 505 506 /* Find an exact fingerprint in the list */ 507 struct pf_os_fingerprint * 508 pf_osfp_find_exact(struct pf_osfp_list *list, struct pf_os_fingerprint *find) 509 { 510 struct pf_os_fingerprint *f; 511 512 SLIST_FOREACH(f, list, fp_next) { 513 if (f->fp_tcpopts == find->fp_tcpopts && 514 f->fp_wsize == find->fp_wsize && 515 f->fp_psize == find->fp_psize && 516 f->fp_mss == find->fp_mss && 517 f->fp_flags == find->fp_flags && 518 f->fp_optcnt == find->fp_optcnt && 519 f->fp_wscale == find->fp_wscale && 520 f->fp_ttl == find->fp_ttl) 521 return (f); 522 } 523 524 return (NULL); 525 } 526 527 /* Insert a fingerprint into the list */ 528 void 529 pf_osfp_insert(struct pf_osfp_list *list, struct pf_os_fingerprint *ins) 530 { 531 struct pf_os_fingerprint *f, *prev = NULL; 532 533 /* XXX need to go semi tree based. can key on tcp options */ 534 535 SLIST_FOREACH(f, list, fp_next) 536 prev = f; 537 if (prev) 538 SLIST_INSERT_AFTER(prev, ins, fp_next); 539 else 540 SLIST_INSERT_HEAD(list, ins, fp_next); 541 } 542 543 /* Fill a fingerprint by its number (from an ioctl) */ 544 int 545 pf_osfp_get(struct pf_osfp_ioctl *fpioc) 546 { 547 struct pf_os_fingerprint *fp; 548 struct pf_osfp_entry *entry; 549 int num = fpioc->fp_getnum; 550 int i = 0; 551 552 553 memset(fpioc, 0, sizeof(*fpioc)); 554 SLIST_FOREACH(fp, &pf_osfp_list, fp_next) { 555 SLIST_FOREACH(entry, &fp->fp_oses, fp_entry) { 556 if (i++ == num) { 557 fpioc->fp_mss = fp->fp_mss; 558 fpioc->fp_wsize = fp->fp_wsize; 559 fpioc->fp_flags = fp->fp_flags; 560 fpioc->fp_psize = fp->fp_psize; 561 fpioc->fp_ttl = fp->fp_ttl; 562 fpioc->fp_wscale = fp->fp_wscale; 563 fpioc->fp_getnum = num; 564 memcpy(&fpioc->fp_os, entry, 565 sizeof(fpioc->fp_os)); 566 return (0); 567 } 568 } 569 } 570 571 return (EBUSY); 572 } 573 574 575 /* Validate that each signature is reachable */ 576 struct pf_os_fingerprint * 577 pf_osfp_validate(void) 578 { 579 struct pf_os_fingerprint *f, *f2, find; 580 581 SLIST_FOREACH(f, &pf_osfp_list, fp_next) { 582 memcpy(&find, f, sizeof(find)); 583 584 /* We do a few MSS/th_win percolations to make things unique */ 585 if (find.fp_mss == 0) 586 find.fp_mss = 128; 587 if (f->fp_flags & PF_OSFP_WSIZE_MSS) 588 find.fp_wsize *= find.fp_mss, 1; 589 else if (f->fp_flags & PF_OSFP_WSIZE_MTU) 590 find.fp_wsize *= (find.fp_mss + 40); 591 else if (f->fp_flags & PF_OSFP_WSIZE_MOD) 592 find.fp_wsize *= 2; 593 if (f != (f2 = pf_osfp_find(&pf_osfp_list, &find, 0))) { 594 if (f2) 595 printf("Found \"%s %s %s\" instead of " 596 "\"%s %s %s\"\n", 597 SLIST_FIRST(&f2->fp_oses)->fp_class_nm, 598 SLIST_FIRST(&f2->fp_oses)->fp_version_nm, 599 SLIST_FIRST(&f2->fp_oses)->fp_subtype_nm, 600 SLIST_FIRST(&f->fp_oses)->fp_class_nm, 601 SLIST_FIRST(&f->fp_oses)->fp_version_nm, 602 SLIST_FIRST(&f->fp_oses)->fp_subtype_nm); 603 else 604 printf("Couldn't find \"%s %s %s\"\n", 605 SLIST_FIRST(&f->fp_oses)->fp_class_nm, 606 SLIST_FIRST(&f->fp_oses)->fp_version_nm, 607 SLIST_FIRST(&f->fp_oses)->fp_subtype_nm); 608 return (f); 609 } 610 } 611 return (NULL); 612 } 613