xref: /openbsd/usr.sbin/tcpdump/pfctl_osfp.c (revision d415bd75)
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
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
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
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
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
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
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 *
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 *
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
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
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 *
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
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
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
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
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
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 *
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 *
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