1 /* $OpenBSD: pfctl_osfp.c,v 1.16 2019/06/28 13:32:51 deraadt Exp $ */
2
3 /*
4 * Copyright (c) 2003 Mike Frantzen <frantzen@openbsd.org>
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
19 #include <sys/types.h>
20 #include <sys/ioctl.h>
21 #include <sys/socket.h>
22
23 #include <netinet/in.h>
24 #include <netinet/ip.h>
25 #include <netinet/ip6.h>
26 #include <net/if.h>
27 #include <net/pfvar.h>
28
29 #include <ctype.h>
30 #include <err.h>
31 #include <errno.h>
32 #include <stdio.h>
33 #include <stdlib.h>
34 #include <string.h>
35
36 #include "privsep.h"
37 #include "pfctl_parser.h"
38
39 #define MAXIMUM(a, b) (((a) > (b)) ? (a) : (b))
40
41 /* #define OSFP_DEBUG 1 */
42 #ifdef OSFP_DEBUG
43 # define DEBUG(fp, str, v...) \
44 fprintf(stderr, "%s:%s:%s " str "\n", (fp)->fp_os.fp_class_nm, \
45 (fp)->fp_os.fp_version_nm, (fp)->fp_os.fp_subtype_nm , ## v);
46 #else
47 # define DEBUG(fp, str, v...) ((void)0)
48 #endif
49
50
51 struct name_entry;
52 LIST_HEAD(name_list, name_entry);
53 struct name_entry {
54 LIST_ENTRY(name_entry) nm_entry;
55 int nm_num;
56 char nm_name[PF_OSFP_LEN];
57
58 struct name_list nm_sublist;
59 int nm_sublist_num;
60 };
61 struct name_list classes = LIST_HEAD_INITIALIZER(&classes);
62 int class_count;
63 int fingerprint_count;
64
65 void add_fingerprint(int, int, struct pf_osfp_ioctl *);
66 struct name_entry *fingerprint_name_entry(struct name_list *, char *);
67 void pfctl_flush_my_fingerprints(struct name_list *);
68 char *get_field(u_char **, size_t *, int *);
69 int get_int(u_char **, size_t *, int *, int *, const char *,
70 int, int, const char *, int);
71 int get_str(u_char **, size_t *, char **, const char *, int,
72 const char *, int);
73 int get_tcpopts(const char *, int, const u_char *,
74 pf_tcpopts_t *, int *, int *, int *, int *, int *,
75 int *);
76 void import_fingerprint(struct pf_osfp_ioctl *);
77 #ifdef OSFP_DEBUG
78 const char *print_ioctl(struct pf_osfp_ioctl *);
79 #endif
80 void print_name_list(int, struct name_list *, const char *);
81 void sort_name_list(int, struct name_list *);
82 struct name_entry *lookup_name_list(struct name_list *, const char *);
83
84 /* Load fingerprints from a file */
85 int
pfctl_file_fingerprints(int dev,int opts,const char * fp_filename)86 pfctl_file_fingerprints(int dev, int opts, const char *fp_filename)
87 {
88 FILE *in;
89 u_char *line;
90 size_t len;
91 int i, fd, lineno = 0;
92 int window, w_mod, ttl, df, psize, p_mod, mss, mss_mod, wscale,
93 wscale_mod, optcnt, ts0;
94 pf_tcpopts_t packed_tcpopts;
95 char *class, *version, *subtype, *desc, *tcpopts;
96 struct pf_osfp_ioctl fp;
97
98 pfctl_flush_my_fingerprints(&classes);
99
100 fd = priv_open_pfosfp();
101 if (fd < 0)
102 return (1);
103
104 if ((in = fdopen(fd, "r")) == NULL) {
105 warn("%s", fp_filename);
106 return (1);
107 }
108
109 class = version = subtype = desc = tcpopts = NULL;
110
111 if ((opts & PF_OPT_NOACTION) == 0)
112 pfctl_clear_fingerprints(dev, opts);
113
114 while ((line = fgetln(in, &len)) != NULL) {
115 lineno++;
116 free(class);
117 free(version);
118 free(subtype);
119 free(desc);
120 free(tcpopts);
121 class = version = subtype = desc = tcpopts = NULL;
122 memset(&fp, 0, sizeof(fp));
123
124 /* Chop off comment */
125 for (i = 0; i < len; i++)
126 if (line[i] == '#') {
127 len = i;
128 break;
129 }
130 /* Chop off whitespace */
131 while (len > 0 && isspace(line[len - 1]))
132 len--;
133 while (len > 0 && isspace(line[0])) {
134 len--;
135 line++;
136 }
137 if (len == 0)
138 continue;
139
140 #define T_DC 0x01 /* Allow don't care */
141 #define T_MSS 0x02 /* Allow MSS multiple */
142 #define T_MTU 0x04 /* Allow MTU multiple */
143 #define T_MOD 0x08 /* Allow modulus */
144
145 #define GET_INT(v, mod, n, ty, mx) \
146 get_int(&line, &len, &v, mod, n, ty, mx, fp_filename, lineno)
147 #define GET_STR(v, n, mn) \
148 get_str(&line, &len, &v, n, mn, fp_filename, lineno)
149
150 if (GET_INT(window, &w_mod, "window size", T_DC|T_MSS|T_MTU|
151 T_MOD, 0xffff) ||
152 GET_INT(ttl, NULL, "ttl", 0, 0xff) ||
153 GET_INT(df, NULL, "don't fragment frag", 0, 1) ||
154 GET_INT(psize, &p_mod, "overall packet size", T_MOD|T_DC,
155 8192) ||
156 GET_STR(tcpopts, "TCP Options", 1) ||
157 GET_STR(class, "OS class", 1) ||
158 GET_STR(version, "OS version", 0) ||
159 GET_STR(subtype, "OS subtype", 0) ||
160 GET_STR(desc, "OS description", 2))
161 continue;
162 if (get_tcpopts(fp_filename, lineno, tcpopts, &packed_tcpopts,
163 &optcnt, &mss, &mss_mod, &wscale, &wscale_mod, &ts0))
164 continue;
165 if (len != 0) {
166 fprintf(stderr, "%s:%d excess field\n", fp_filename,
167 lineno);
168 continue;
169 }
170
171 fp.fp_ttl = ttl;
172 if (df)
173 fp.fp_flags |= PF_OSFP_DF;
174 switch (w_mod) {
175 case 0:
176 break;
177 case T_DC:
178 fp.fp_flags |= PF_OSFP_WSIZE_DC;
179 break;
180 case T_MSS:
181 fp.fp_flags |= PF_OSFP_WSIZE_MSS;
182 break;
183 case T_MTU:
184 fp.fp_flags |= PF_OSFP_WSIZE_MTU;
185 break;
186 case T_MOD:
187 fp.fp_flags |= PF_OSFP_WSIZE_MOD;
188 break;
189 }
190 fp.fp_wsize = window;
191
192 switch (p_mod) {
193 case T_DC:
194 fp.fp_flags |= PF_OSFP_PSIZE_DC;
195 break;
196 case T_MOD:
197 fp.fp_flags |= PF_OSFP_PSIZE_MOD;
198 }
199 fp.fp_psize = psize;
200
201
202 switch (wscale_mod) {
203 case T_DC:
204 fp.fp_flags |= PF_OSFP_WSCALE_DC;
205 break;
206 case T_MOD:
207 fp.fp_flags |= PF_OSFP_WSCALE_MOD;
208 }
209 fp.fp_wscale = wscale;
210
211 switch (mss_mod) {
212 case T_DC:
213 fp.fp_flags |= PF_OSFP_MSS_DC;
214 break;
215 case T_MOD:
216 fp.fp_flags |= PF_OSFP_MSS_MOD;
217 break;
218 }
219 fp.fp_mss = mss;
220
221 fp.fp_tcpopts = packed_tcpopts;
222 fp.fp_optcnt = optcnt;
223 if (ts0)
224 fp.fp_flags |= PF_OSFP_TS0;
225
226 if (class[0] == '@')
227 fp.fp_os.fp_enflags |= PF_OSFP_GENERIC;
228 if (class[0] == '*')
229 fp.fp_os.fp_enflags |= PF_OSFP_NODETAIL;
230
231 if (class[0] == '@' || class[0] == '*')
232 strlcpy(fp.fp_os.fp_class_nm, class + 1,
233 sizeof(fp.fp_os.fp_class_nm));
234 else
235 strlcpy(fp.fp_os.fp_class_nm, class,
236 sizeof(fp.fp_os.fp_class_nm));
237 strlcpy(fp.fp_os.fp_version_nm, version,
238 sizeof(fp.fp_os.fp_version_nm));
239 strlcpy(fp.fp_os.fp_subtype_nm, subtype,
240 sizeof(fp.fp_os.fp_subtype_nm));
241
242 add_fingerprint(dev, opts, &fp);
243
244 fp.fp_flags |= (PF_OSFP_DF | PF_OSFP_INET6);
245 fp.fp_psize += sizeof(struct ip6_hdr) - sizeof(struct ip);
246 add_fingerprint(dev, opts, &fp);
247 }
248
249 free(class);
250 free(version);
251 free(subtype);
252 free(desc);
253 free(tcpopts);
254
255 if (opts & PF_OPT_VERBOSE2)
256 printf("Loaded %d passive OS fingerprints\n",
257 fingerprint_count);
258 fclose(in);
259 return (0);
260 }
261
262 /* flush the kernel's fingerprints */
263 void
pfctl_clear_fingerprints(int dev,int opts)264 pfctl_clear_fingerprints(int dev, int opts)
265 {
266 if (ioctl(dev, DIOCOSFPFLUSH) == -1)
267 err(1, "DIOCOSFPFLUSH");
268 }
269
270 /* flush pfctl's view of the fingerprints */
271 void
pfctl_flush_my_fingerprints(struct name_list * list)272 pfctl_flush_my_fingerprints(struct name_list *list)
273 {
274 struct name_entry *nm;
275
276 while ((nm = LIST_FIRST(list)) != NULL) {
277 LIST_REMOVE(nm, nm_entry);
278 pfctl_flush_my_fingerprints(&nm->nm_sublist);
279 free(nm);
280 }
281 fingerprint_count = 0;
282 class_count = 0;
283 }
284
285 /* Fetch the active fingerprints from the kernel */
286 int
pfctl_load_fingerprints(int dev,int opts)287 pfctl_load_fingerprints(int dev, int opts)
288 {
289 struct pf_osfp_ioctl io;
290 int i;
291
292 pfctl_flush_my_fingerprints(&classes);
293
294 for (i = 0; i >= 0; i++) {
295 memset(&io, 0, sizeof(io));
296 io.fp_getnum = i;
297 if (ioctl(dev, DIOCOSFPGET, &io) == -1) {
298 if (errno == EBUSY)
299 break;
300 warn("DIOCOSFPGET");
301 return (1);
302 }
303 import_fingerprint(&io);
304 }
305 return (0);
306 }
307
308 /* List the fingerprints */
309 void
pfctl_show_fingerprints(int opts)310 pfctl_show_fingerprints(int opts)
311 {
312 printf("Passive OS Fingerprints:\n");
313 printf("\tClass\tVersion\tSubtype(subversion)\n");
314 printf("\t-----\t-------\t-------------------\n");
315 sort_name_list(opts, &classes);
316 print_name_list(opts, &classes, "\t");
317 }
318
319 /* Lookup a fingerprint */
320 pf_osfp_t
pfctl_get_fingerprint(const char * name)321 pfctl_get_fingerprint(const char *name)
322 {
323 struct name_entry *nm, *class_nm, *version_nm, *subtype_nm;
324 pf_osfp_t ret = PF_OSFP_NOMATCH;
325 int class, version, subtype;
326 int unp_class, unp_version, unp_subtype;
327 int wr_len, version_len, subtype_len;
328 char *ptr, *wr_name;
329
330 if (strcasecmp(name, "unknown") == 0)
331 return (PF_OSFP_UNKNOWN);
332
333 /* Try most likely no version and no subtype */
334 if ((nm = lookup_name_list(&classes, name))) {
335 class = nm->nm_num;
336 version = PF_OSFP_ANY;
337 subtype = PF_OSFP_ANY;
338 goto found;
339 } else {
340
341 /* Chop it up into class/version/subtype */
342
343 if ((wr_name = strdup(name)) == NULL)
344 err(1, "malloc");
345 if ((ptr = strchr(wr_name, ' ')) == NULL) {
346 free(wr_name);
347 return (PF_OSFP_NOMATCH);
348 }
349 *ptr++ = '\0';
350
351 /* The class is easy to find since it is delimited by a space */
352 if ((class_nm = lookup_name_list(&classes, wr_name)) == NULL) {
353 free(wr_name);
354 return (PF_OSFP_NOMATCH);
355 }
356 class = class_nm->nm_num;
357
358 /* Try no subtype */
359 if ((version_nm = lookup_name_list(&class_nm->nm_sublist, ptr)))
360 {
361 version = version_nm->nm_num;
362 subtype = PF_OSFP_ANY;
363 free(wr_name);
364 goto found;
365 }
366
367
368 /*
369 * There must be a version and a subtype.
370 * We'll do some fuzzy matching to pick up things like:
371 * Linux 2.2.14 (version=2.2 subtype=14)
372 * FreeBSD 4.0-STABLE (version=4.0 subtype=STABLE)
373 * Windows 2000 SP2 (version=2000 subtype=SP2)
374 */
375 #define CONNECTOR(x) ((x) == '.' || (x) == ' ' || (x) == '\t' || (x) == '-')
376 wr_len = strlen(ptr);
377 LIST_FOREACH(version_nm, &class_nm->nm_sublist, nm_entry) {
378 version_len = strlen(version_nm->nm_name);
379 if (wr_len < version_len + 2 ||
380 !CONNECTOR(ptr[version_len]))
381 continue;
382 /* first part of the string must be version */
383 if (strncasecmp(ptr, version_nm->nm_name,
384 version_len))
385 continue;
386
387 LIST_FOREACH(subtype_nm, &version_nm->nm_sublist,
388 nm_entry) {
389 subtype_len = strlen(subtype_nm->nm_name);
390 if (wr_len != version_len + subtype_len + 1)
391 continue;
392
393 /* last part of the string must be subtype */
394 if (strcasecmp(&ptr[version_len+1],
395 subtype_nm->nm_name) != 0)
396 continue;
397
398 /* Found it!! */
399 version = version_nm->nm_num;
400 subtype = subtype_nm->nm_num;
401 free(wr_name);
402 goto found;
403 }
404 }
405
406 free(wr_name);
407 return (PF_OSFP_NOMATCH);
408 }
409
410 found:
411 PF_OSFP_PACK(ret, class, version, subtype);
412 if (ret != PF_OSFP_NOMATCH) {
413 PF_OSFP_UNPACK(ret, unp_class, unp_version, unp_subtype);
414 if (class != unp_class) {
415 fprintf(stderr, "warning: fingerprint table overflowed "
416 "classes\n");
417 return (PF_OSFP_NOMATCH);
418 }
419 if (version != unp_version) {
420 fprintf(stderr, "warning: fingerprint table overflowed "
421 "versions\n");
422 return (PF_OSFP_NOMATCH);
423 }
424 if (subtype != unp_subtype) {
425 fprintf(stderr, "warning: fingerprint table overflowed "
426 "subtypes\n");
427 return (PF_OSFP_NOMATCH);
428 }
429 }
430 if (ret == PF_OSFP_ANY) {
431 /* should never happen */
432 fprintf(stderr, "warning: fingerprint packed to 'any'\n");
433 return (PF_OSFP_NOMATCH);
434 }
435
436 return (ret);
437 }
438
439 /* Lookup a fingerprint name by ID */
440 char *
pfctl_lookup_fingerprint(pf_osfp_t fp,char * buf,size_t len)441 pfctl_lookup_fingerprint(pf_osfp_t fp, char *buf, size_t len)
442 {
443 int class, version, subtype;
444 struct name_list *list;
445 struct name_entry *nm;
446
447 u_char *class_name, *version_name, *subtype_name;
448 class_name = version_name = subtype_name = NULL;
449
450 if (fp == PF_OSFP_UNKNOWN) {
451 strlcpy(buf, "unknown", len);
452 return (buf);
453 }
454 if (fp == PF_OSFP_ANY) {
455 strlcpy(buf, "any", len);
456 return (buf);
457 }
458
459 PF_OSFP_UNPACK(fp, class, version, subtype);
460 if (class >= (1 << _FP_CLASS_BITS) ||
461 version >= (1 << _FP_VERSION_BITS) ||
462 subtype >= (1 << _FP_SUBTYPE_BITS)) {
463 warnx("PF_OSFP_UNPACK(0x%x) failed!!", fp);
464 strlcpy(buf, "nomatch", len);
465 return (buf);
466 }
467
468 LIST_FOREACH(nm, &classes, nm_entry) {
469 if (nm->nm_num == class) {
470 class_name = nm->nm_name;
471 if (version == PF_OSFP_ANY)
472 goto found;
473 list = &nm->nm_sublist;
474 LIST_FOREACH(nm, list, nm_entry) {
475 if (nm->nm_num == version) {
476 version_name = nm->nm_name;
477 if (subtype == PF_OSFP_ANY)
478 goto found;
479 list = &nm->nm_sublist;
480 LIST_FOREACH(nm, list, nm_entry) {
481 if (nm->nm_num == subtype) {
482 subtype_name =
483 nm->nm_name;
484 goto found;
485 }
486 } /* foreach subtype */
487 strlcpy(buf, "nomatch", len);
488 return (buf);
489 }
490 } /* foreach version */
491 strlcpy(buf, "nomatch", len);
492 return (buf);
493 }
494 } /* foreach class */
495
496 strlcpy(buf, "nomatch", len);
497 return (buf);
498
499 found:
500 snprintf(buf, len, "%s", class_name);
501 if (version_name) {
502 strlcat(buf, " ", len);
503 strlcat(buf, version_name, len);
504 if (subtype_name) {
505 if (strchr(version_name, ' '))
506 strlcat(buf, " ", len);
507 else if (strchr(version_name, '.') &&
508 isdigit(*subtype_name))
509 strlcat(buf, ".", len);
510 else
511 strlcat(buf, " ", len);
512 strlcat(buf, subtype_name, len);
513 }
514 }
515 return (buf);
516 }
517
518 /* lookup a name in a list */
519 struct name_entry *
lookup_name_list(struct name_list * list,const char * name)520 lookup_name_list(struct name_list *list, const char *name)
521 {
522 struct name_entry *nm;
523 LIST_FOREACH(nm, list, nm_entry)
524 if (strcasecmp(name, nm->nm_name) == 0)
525 return (nm);
526
527 return (NULL);
528 }
529
530
531 void
add_fingerprint(int dev,int opts,struct pf_osfp_ioctl * fp)532 add_fingerprint(int dev, int opts, struct pf_osfp_ioctl *fp)
533 {
534 struct pf_osfp_ioctl fptmp;
535 struct name_entry *nm_class, *nm_version, *nm_subtype;
536 int class, version, subtype;
537
538 /* We expand #-# or #.#-#.# version/subtypes into multiple fingerprints */
539 #define EXPAND(field) do { \
540 int _dot = -1, _start = -1, _end = -1, _i = 0; \
541 /* pick major version out of #.# */ \
542 if (isdigit(fp->field[_i]) && fp->field[_i+1] == '.') { \
543 _dot = fp->field[_i] - '0'; \
544 _i += 2; \
545 } \
546 if (isdigit(fp->field[_i])) \
547 _start = fp->field[_i++] - '0'; \
548 else \
549 break; \
550 if (isdigit(fp->field[_i])) \
551 _start = (_start * 10) + fp->field[_i++] - '0'; \
552 if (fp->field[_i++] != '-') \
553 break; \
554 if (isdigit(fp->field[_i]) && fp->field[_i+1] == '.' && \
555 fp->field[_i] - '0' == _dot) \
556 _i += 2; \
557 else if (_dot != -1) \
558 break; \
559 if (isdigit(fp->field[_i])) \
560 _end = fp->field[_i++] - '0'; \
561 else \
562 break; \
563 if (isdigit(fp->field[_i])) \
564 _end = (_end * 10) + fp->field[_i++] - '0'; \
565 if (isdigit(fp->field[_i])) \
566 _end = (_end * 10) + fp->field[_i++] - '0'; \
567 if (fp->field[_i] != '\0') \
568 break; \
569 memcpy(&fptmp, fp, sizeof(fptmp)); \
570 for (;_start <= _end; _start++) { \
571 memset(fptmp.field, 0, sizeof(fptmp.field)); \
572 fptmp.fp_os.fp_enflags |= PF_OSFP_EXPANDED; \
573 if (_dot == -1) \
574 snprintf(fptmp.field, sizeof(fptmp.field), \
575 "%d", _start); \
576 else \
577 snprintf(fptmp.field, sizeof(fptmp.field), \
578 "%d.%d", _dot, _start); \
579 add_fingerprint(dev, opts, &fptmp); \
580 } \
581 } while(0)
582
583 /* We allow "#-#" as a version or subtype and we'll expand it */
584 EXPAND(fp_os.fp_version_nm);
585 EXPAND(fp_os.fp_subtype_nm);
586
587 if (strcasecmp(fp->fp_os.fp_class_nm, "nomatch") == 0)
588 errx(1, "fingerprint class \"nomatch\" is reserved");
589
590 version = PF_OSFP_ANY;
591 subtype = PF_OSFP_ANY;
592
593 nm_class = fingerprint_name_entry(&classes, fp->fp_os.fp_class_nm);
594 if (nm_class->nm_num == 0)
595 nm_class->nm_num = ++class_count;
596 class = nm_class->nm_num;
597
598 nm_version = fingerprint_name_entry(&nm_class->nm_sublist,
599 fp->fp_os.fp_version_nm);
600 if (nm_version) {
601 if (nm_version->nm_num == 0)
602 nm_version->nm_num = ++nm_class->nm_sublist_num;
603 version = nm_version->nm_num;
604 nm_subtype = fingerprint_name_entry(&nm_version->nm_sublist,
605 fp->fp_os.fp_subtype_nm);
606 if (nm_subtype) {
607 if (nm_subtype->nm_num == 0)
608 nm_subtype->nm_num =
609 ++nm_version->nm_sublist_num;
610 subtype = nm_subtype->nm_num;
611 }
612 }
613
614
615 DEBUG(fp, "\tsignature %d:%d:%d %s", class, version, subtype,
616 print_ioctl(fp));
617
618 PF_OSFP_PACK(fp->fp_os.fp_os, class, version, subtype);
619 fingerprint_count++;
620
621 #ifdef FAKE_PF_KERNEL
622 /* Linked to the sys/net/pf_osfp.c. Call pf_osfp_add() */
623 if ((errno = pf_osfp_add(fp)))
624 #else
625 if ((opts & PF_OPT_NOACTION) == 0 && ioctl(dev, DIOCOSFPADD, fp) == -1)
626 #endif /* FAKE_PF_KERNEL */
627 {
628 if (errno == EEXIST) {
629 warn("Duplicate signature for %s %s %s",
630 fp->fp_os.fp_class_nm,
631 fp->fp_os.fp_version_nm,
632 fp->fp_os.fp_subtype_nm);
633
634 } else {
635 err(1, "DIOCOSFPADD");
636 }
637 }
638 }
639
640 /* import a fingerprint from the kernel */
641 void
import_fingerprint(struct pf_osfp_ioctl * fp)642 import_fingerprint(struct pf_osfp_ioctl *fp)
643 {
644 struct name_entry *nm_class, *nm_version, *nm_subtype;
645 int class, version, subtype;
646
647 PF_OSFP_UNPACK(fp->fp_os.fp_os, class, version, subtype);
648
649 nm_class = fingerprint_name_entry(&classes, fp->fp_os.fp_class_nm);
650 if (nm_class->nm_num == 0) {
651 nm_class->nm_num = class;
652 class_count = MAXIMUM(class_count, class);
653 }
654
655 nm_version = fingerprint_name_entry(&nm_class->nm_sublist,
656 fp->fp_os.fp_version_nm);
657 if (nm_version) {
658 if (nm_version->nm_num == 0) {
659 nm_version->nm_num = version;
660 nm_class->nm_sublist_num = MAXIMUM(nm_class->nm_sublist_num,
661 version);
662 }
663 nm_subtype = fingerprint_name_entry(&nm_version->nm_sublist,
664 fp->fp_os.fp_subtype_nm);
665 if (nm_subtype) {
666 if (nm_subtype->nm_num == 0) {
667 nm_subtype->nm_num = subtype;
668 nm_version->nm_sublist_num =
669 MAXIMUM(nm_version->nm_sublist_num, subtype);
670 }
671 }
672 }
673
674
675 fingerprint_count++;
676 DEBUG(fp, "import signature %d:%d:%d", class, version, subtype);
677 }
678
679 /* Find an entry for a fingerprints class/version/subtype */
680 struct name_entry *
fingerprint_name_entry(struct name_list * list,char * name)681 fingerprint_name_entry(struct name_list *list, char *name)
682 {
683 struct name_entry *nm_entry;
684
685 if (name == NULL || strlen(name) == 0)
686 return (NULL);
687
688 LIST_FOREACH(nm_entry, list, nm_entry) {
689 if (strcasecmp(nm_entry->nm_name, name) == 0) {
690 /* We'll move this to the front of the list later */
691 LIST_REMOVE(nm_entry, nm_entry);
692 break;
693 }
694 }
695 if (nm_entry == NULL) {
696 nm_entry = calloc(1, sizeof(*nm_entry));
697 if (nm_entry == NULL)
698 err(1, "calloc");
699 LIST_INIT(&nm_entry->nm_sublist);
700 strlcpy(nm_entry->nm_name, name, sizeof(nm_entry->nm_name));
701 }
702 LIST_INSERT_HEAD(list, nm_entry, nm_entry);
703 return (nm_entry);
704 }
705
706
707 void
print_name_list(int opts,struct name_list * nml,const char * prefix)708 print_name_list(int opts, struct name_list *nml, const char *prefix)
709 {
710 char newprefix[32];
711 struct name_entry *nm;
712
713 LIST_FOREACH(nm, nml, nm_entry) {
714 snprintf(newprefix, sizeof(newprefix), "%s%s\t", prefix,
715 nm->nm_name);
716 printf("%s\n", newprefix);
717 print_name_list(opts, &nm->nm_sublist, newprefix);
718 }
719 }
720
721 void
sort_name_list(int opts,struct name_list * nml)722 sort_name_list(int opts, struct name_list *nml)
723 {
724 struct name_list new;
725 struct name_entry *nm, *nmsearch, *nmlast;
726
727 /* yes yes, it's a very slow sort. so sue me */
728
729 LIST_INIT(&new);
730
731 while ((nm = LIST_FIRST(nml)) != NULL) {
732 LIST_REMOVE(nm, nm_entry);
733 nmlast = NULL;
734 LIST_FOREACH(nmsearch, &new, nm_entry) {
735 if (strcasecmp(nmsearch->nm_name, nm->nm_name) > 0) {
736 LIST_INSERT_BEFORE(nmsearch, nm, nm_entry);
737 break;
738 }
739 nmlast = nmsearch;
740 }
741 if (nmsearch == NULL) {
742 if (nmlast)
743 LIST_INSERT_AFTER(nmlast, nm, nm_entry);
744 else
745 LIST_INSERT_HEAD(&new, nm, nm_entry);
746 }
747
748 sort_name_list(opts, &nm->nm_sublist);
749 }
750 nmlast = NULL;
751 while ((nm = LIST_FIRST(&new)) != NULL) {
752 LIST_REMOVE(nm, nm_entry);
753 if (nmlast == NULL)
754 LIST_INSERT_HEAD(nml, nm, nm_entry);
755 else
756 LIST_INSERT_AFTER(nmlast, nm, nm_entry);
757 nmlast = nm;
758 }
759 }
760
761 /* parse the next integer in a formatted config file line */
762 int
get_int(u_char ** line,size_t * len,int * var,int * mod,const char * name,int flags,int max,const char * filename,int lineno)763 get_int(u_char **line, size_t *len, int *var, int *mod,
764 const char *name, int flags, int max, const char *filename, int lineno)
765 {
766 int fieldlen, i;
767 u_char *field;
768 long val = 0;
769
770 if (mod)
771 *mod = 0;
772 *var = 0;
773
774 field = get_field(line, len, &fieldlen);
775 if (field == NULL)
776 return (1);
777 if (fieldlen == 0) {
778 fprintf(stderr, "%s:%d empty %s\n", filename, lineno, name);
779 return (1);
780 }
781
782 i = 0;
783 if ((*field == '%' || *field == 'S' || *field == 'T' || *field == '*')
784 && fieldlen >= 1) {
785 switch (*field) {
786 case 'S':
787 if (mod && (flags & T_MSS))
788 *mod = T_MSS;
789 if (fieldlen == 1)
790 return (0);
791 break;
792 case 'T':
793 if (mod && (flags & T_MTU))
794 *mod = T_MTU;
795 if (fieldlen == 1)
796 return (0);
797 break;
798 case '*':
799 if (fieldlen != 1) {
800 fprintf(stderr, "%s:%d long '%c' %s\n",
801 filename, lineno, *field, name);
802 return (1);
803 }
804 if (mod && (flags & T_DC)) {
805 *mod = T_DC;
806 return (0);
807 }
808 case '%':
809 if (mod && (flags & T_MOD))
810 *mod = T_MOD;
811 if (fieldlen == 1) {
812 fprintf(stderr, "%s:%d modulus %s must have a "
813 "value\n", filename, lineno, name);
814 return (1);
815 }
816 break;
817 }
818 if (mod == NULL || *mod == 0) {
819 fprintf(stderr, "%s:%d does not allow %c' %s\n",
820 filename, lineno, *field, name);
821 return (1);
822 }
823 i++;
824 }
825
826 for (; i < fieldlen; i++) {
827 if (field[i] < '0' || field[i] > '9') {
828 fprintf(stderr, "%s:%d non-digit character in %s\n",
829 filename, lineno, name);
830 return (1);
831 }
832 val = val * 10 + field[i] - '0';
833 if (val < 0) {
834 fprintf(stderr, "%s:%d %s overflowed\n", filename,
835 lineno, name);
836 return (1);
837 }
838 }
839
840 if (val > max) {
841 fprintf(stderr, "%s:%d %s value %ld > %d\n", filename, lineno,
842 name, val, max);
843 return (1);
844 }
845 *var = (int)val;
846
847 return (0);
848 }
849
850 /* parse the next string in a formatted config file line */
851 int
get_str(u_char ** line,size_t * len,char ** v,const char * name,int minlen,const char * filename,int lineno)852 get_str(u_char **line, size_t *len, char **v, const char *name, int minlen,
853 const char *filename, int lineno)
854 {
855 int fieldlen;
856 char *ptr;
857
858 ptr = get_field(line, len, &fieldlen);
859 if (ptr == NULL)
860 return (1);
861 if (fieldlen < minlen) {
862 fprintf(stderr, "%s:%d too short %s\n", filename, lineno, name);
863 return (1);
864 }
865 if ((*v = malloc(fieldlen + 1)) == NULL) {
866 perror("malloc()");
867 return (1);
868 }
869 memcpy(*v, ptr, fieldlen);
870 (*v)[fieldlen] = '\0';
871
872 return (0);
873 }
874
875 /* Parse out the TCP opts */
876 int
get_tcpopts(const char * filename,int lineno,const u_char * tcpopts,pf_tcpopts_t * packed,int * optcnt,int * mss,int * mss_mod,int * wscale,int * wscale_mod,int * ts0)877 get_tcpopts(const char *filename, int lineno, const u_char *tcpopts,
878 pf_tcpopts_t *packed, int *optcnt, int *mss, int *mss_mod, int *wscale,
879 int *wscale_mod, int *ts0)
880 {
881 int i, opt;
882
883 *packed = 0;
884 *optcnt = 0;
885 *wscale = 0;
886 *wscale_mod = T_DC;
887 *mss = 0;
888 *mss_mod = T_DC;
889 *ts0 = 0;
890 if (strcmp(tcpopts, ".") == 0)
891 return (0);
892
893 for (i = 0; tcpopts[i] && *optcnt < PF_OSFP_MAX_OPTS;) {
894 switch ((opt = toupper(tcpopts[i++]))) {
895 case 'N': /* FALLTHROUGH */
896 case 'S':
897 *packed = (*packed << PF_OSFP_TCPOPT_BITS) |
898 (opt == 'N' ? PF_OSFP_TCPOPT_NOP :
899 PF_OSFP_TCPOPT_SACK);
900 break;
901 case 'W': /* FALLTHROUGH */
902 case 'M': {
903 int *this_mod, *this;
904
905 if (opt == 'W') {
906 this = wscale;
907 this_mod = wscale_mod;
908 } else {
909 this = mss;
910 this_mod = mss_mod;
911 }
912 *this = 0;
913 *this_mod = 0;
914
915 *packed = (*packed << PF_OSFP_TCPOPT_BITS) |
916 (opt == 'W' ? PF_OSFP_TCPOPT_WSCALE :
917 PF_OSFP_TCPOPT_MSS);
918 if (tcpopts[i] == '*' && (tcpopts[i + 1] == '\0' ||
919 tcpopts[i + 1] == ',')) {
920 *this_mod = T_DC;
921 i++;
922 break;
923 }
924
925 if (tcpopts[i] == '%') {
926 *this_mod = T_MOD;
927 i++;
928 }
929 do {
930 if (!isdigit(tcpopts[i])) {
931 fprintf(stderr, "%s:%d unknown "
932 "character '%c' in %c TCP opt\n",
933 filename, lineno, tcpopts[i], opt);
934 return (1);
935 }
936 *this = (*this * 10) + tcpopts[i++] - '0';
937 } while(tcpopts[i] != ',' && tcpopts[i] != '\0');
938 break;
939 }
940 case 'T':
941 if (tcpopts[i] == '0') {
942 *ts0 = 1;
943 i++;
944 }
945 *packed = (*packed << PF_OSFP_TCPOPT_BITS) |
946 PF_OSFP_TCPOPT_TS;
947 break;
948 }
949 (*optcnt) ++;
950 if (tcpopts[i] == '\0')
951 break;
952 if (tcpopts[i] != ',') {
953 fprintf(stderr, "%s:%d unknown option to %c TCP opt\n",
954 filename, lineno, opt);
955 return (1);
956 }
957 i++;
958 }
959
960 return (0);
961 }
962
963 /* rip the next field out of a formatted config file line */
964 char *
get_field(u_char ** line,size_t * len,int * fieldlen)965 get_field(u_char **line, size_t *len, int *fieldlen)
966 {
967 char *ret, *ptr = *line;
968 size_t plen = *len;
969
970
971 while (plen && isspace((unsigned char)*ptr)) {
972 plen--;
973 ptr++;
974 }
975 ret = ptr;
976 *fieldlen = 0;
977
978 for (; plen > 0 && *ptr != ':'; plen--, ptr++)
979 (*fieldlen)++;
980 if (plen) {
981 *line = ptr + 1;
982 *len = plen - 1;
983 } else {
984 *len = 0;
985 }
986 while (*fieldlen && isspace((unsigned char)ret[*fieldlen - 1]))
987 (*fieldlen)--;
988 return (ret);
989 }
990
991
992 #ifdef OSFP_DEBUG
993 const char *
print_ioctl(struct pf_osfp_ioctl * fp)994 print_ioctl(struct pf_osfp_ioctl *fp)
995 {
996 static char buf[1024];
997 char tmp[32];
998 int i, opt;
999
1000 *buf = '\0';
1001 if (fp->fp_flags & PF_OSFP_WSIZE_DC)
1002 strlcat(buf, "*", sizeof(buf));
1003 else if (fp->fp_flags & PF_OSFP_WSIZE_MSS)
1004 strlcat(buf, "S", sizeof(buf));
1005 else if (fp->fp_flags & PF_OSFP_WSIZE_MTU)
1006 strlcat(buf, "T", sizeof(buf));
1007 else {
1008 if (fp->fp_flags & PF_OSFP_WSIZE_MOD)
1009 strlcat(buf, "%", sizeof(buf));
1010 snprintf(tmp, sizeof(tmp), "%d", fp->fp_wsize);
1011 strlcat(buf, tmp, sizeof(buf));
1012 }
1013 strlcat(buf, ":", sizeof(buf));
1014
1015 snprintf(tmp, sizeof(tmp), "%d", fp->fp_ttl);
1016 strlcat(buf, tmp, sizeof(buf));
1017 strlcat(buf, ":", sizeof(buf));
1018
1019 if (fp->fp_flags & PF_OSFP_DF)
1020 strlcat(buf, "1", sizeof(buf));
1021 else
1022 strlcat(buf, "0", sizeof(buf));
1023 strlcat(buf, ":", sizeof(buf));
1024
1025 if (fp->fp_flags & PF_OSFP_PSIZE_DC)
1026 strlcat(buf, "*", sizeof(buf));
1027 else {
1028 if (fp->fp_flags & PF_OSFP_PSIZE_MOD)
1029 strlcat(buf, "%", sizeof(buf));
1030 snprintf(tmp, sizeof(tmp), "%d", fp->fp_psize);
1031 strlcat(buf, tmp, sizeof(buf));
1032 }
1033 strlcat(buf, ":", sizeof(buf));
1034
1035 if (fp->fp_optcnt == 0)
1036 strlcat(buf, ".", sizeof(buf));
1037 for (i = fp->fp_optcnt - 1; i >= 0; i--) {
1038 opt = fp->fp_tcpopts >> (i * PF_OSFP_TCPOPT_BITS);
1039 opt &= (1 << PF_OSFP_TCPOPT_BITS) - 1;
1040 switch (opt) {
1041 case PF_OSFP_TCPOPT_NOP:
1042 strlcat(buf, "N", sizeof(buf));
1043 break;
1044 case PF_OSFP_TCPOPT_SACK:
1045 strlcat(buf, "S", sizeof(buf));
1046 break;
1047 case PF_OSFP_TCPOPT_TS:
1048 strlcat(buf, "T", sizeof(buf));
1049 if (fp->fp_flags & PF_OSFP_TS0)
1050 strlcat(buf, "0", sizeof(buf));
1051 break;
1052 case PF_OSFP_TCPOPT_MSS:
1053 strlcat(buf, "M", sizeof(buf));
1054 if (fp->fp_flags & PF_OSFP_MSS_DC)
1055 strlcat(buf, "*", sizeof(buf));
1056 else {
1057 if (fp->fp_flags & PF_OSFP_MSS_MOD)
1058 strlcat(buf, "%", sizeof(buf));
1059 snprintf(tmp, sizeof(tmp), "%d", fp->fp_mss);
1060 strlcat(buf, tmp, sizeof(buf));
1061 }
1062 break;
1063 case PF_OSFP_TCPOPT_WSCALE:
1064 strlcat(buf, "W", sizeof(buf));
1065 if (fp->fp_flags & PF_OSFP_WSCALE_DC)
1066 strlcat(buf, "*", sizeof(buf));
1067 else {
1068 if (fp->fp_flags & PF_OSFP_WSCALE_MOD)
1069 strlcat(buf, "%", sizeof(buf));
1070 snprintf(tmp, sizeof(tmp), "%d", fp->fp_wscale);
1071 strlcat(buf, tmp, sizeof(buf));
1072 }
1073 break;
1074 }
1075
1076 if (i != 0)
1077 strlcat(buf, ",", sizeof(buf));
1078 }
1079 strlcat(buf, ":", sizeof(buf));
1080
1081 strlcat(buf, fp->fp_os.fp_class_nm, sizeof(buf));
1082 strlcat(buf, ":", sizeof(buf));
1083 strlcat(buf, fp->fp_os.fp_version_nm, sizeof(buf));
1084 strlcat(buf, ":", sizeof(buf));
1085 strlcat(buf, fp->fp_os.fp_subtype_nm, sizeof(buf));
1086 strlcat(buf, ":", sizeof(buf));
1087
1088 snprintf(tmp, sizeof(tmp), "TcpOpts %d 0x%llx", fp->fp_optcnt,
1089 (long long int)fp->fp_tcpopts);
1090 strlcat(buf, tmp, sizeof(buf));
1091
1092 return (buf);
1093 }
1094 #endif
1095