xref: /openbsd-src/usr.sbin/tcpdump/pfctl_osfp.c (revision 0b7734b3d77bb9b21afec6f4621cae6c805dbd45)
1 /*	$OpenBSD: pfctl_osfp.c,v 1.11 2015/12/05 19:27:17 mmcc 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 
37 #include "privsep.h"
38 #include "pfctl_parser.h"
39 
40 #ifndef MIN
41 # define MIN(a,b)	(((a) < (b)) ? (a) : (b))
42 #endif /* MIN */
43 #ifndef MAX
44 # define MAX(a,b)	(((a) > (b)) ? (a) : (b))
45 #endif /* MAX */
46 
47 
48 #if 0
49 # define DEBUG(fp, str, v...) \
50 	fprintf(stderr, "%s:%s:%s " str "\n", (fp)->fp_os.fp_class_nm, \
51 	    (fp)->fp_os.fp_version_nm, (fp)->fp_os.fp_subtype_nm , ## v);
52 #else
53 # define DEBUG(fp, str, v...) ((void)0)
54 #endif
55 
56 
57 struct name_entry;
58 LIST_HEAD(name_list, name_entry);
59 struct name_entry {
60 	LIST_ENTRY(name_entry)	nm_entry;
61 	int			nm_num;
62 	char			nm_name[PF_OSFP_LEN];
63 
64 	struct name_list	nm_sublist;
65 	int			nm_sublist_num;
66 };
67 struct name_list classes = LIST_HEAD_INITIALIZER(&classes);
68 int class_count;
69 int fingerprint_count;
70 
71 void			 add_fingerprint(int, int, struct pf_osfp_ioctl *);
72 struct name_entry	*fingerprint_name_entry(struct name_list *, char *);
73 void			 pfctl_flush_my_fingerprints(struct name_list *);
74 char			*get_field(u_char **, size_t *, int *);
75 int			 get_int(u_char **, size_t *, int *, int *, const char *,
76 			     int, int, const char *, int);
77 int			 get_str(u_char **, size_t *, char **, const char *, int,
78 			     const char *, int);
79 int			 get_tcpopts(const char *, int, const u_char *,
80 			    pf_tcpopts_t *, int *, int *, int *, int *, int *,
81 			    int *);
82 void			 import_fingerprint(struct pf_osfp_ioctl *);
83 const char		*print_ioctl(struct pf_osfp_ioctl *);
84 void			 print_name_list(int, struct name_list *, const char *);
85 void			 sort_name_list(int, struct name_list *);
86 struct name_entry	*lookup_name_list(struct name_list *, const char *);
87 
88 /* XXX arbitrary */
89 #define MAX_FP_LINE 1024
90 
91 /* Load fingerprints from a file */
92 int
93 pfctl_file_fingerprints(int dev, int opts, const char *fp_filename)
94 {
95 	u_char buf[MAX_FP_LINE];
96 	u_char *line;
97 	size_t len;
98 	int i, lineno = 0;
99 	int window, w_mod, ttl, df, psize, p_mod, mss, mss_mod, wscale,
100 	    wscale_mod, optcnt, ts0;
101 	pf_tcpopts_t packed_tcpopts;
102 	char *class, *version, *subtype, *desc, *tcpopts;
103 	struct pf_osfp_ioctl fp;
104 
105 	pfctl_flush_my_fingerprints(&classes);
106 	class = version = subtype = desc = tcpopts = NULL;
107 
108 	if ((opts & PF_OPT_NOACTION) == 0)
109 		pfctl_clear_fingerprints(dev, opts);
110 
111 	priv_getlines(FTAB_PFOSFP);
112 	while ((len = priv_getline(buf, sizeof(buf))) > 0) {
113 		buf[len -1] = '\n';
114 		line = buf;
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 
254 	if (opts & PF_OPT_VERBOSE2)
255 		printf("Loaded %d passive OS fingerprints\n",
256 		    fingerprint_count);
257 	return (0);
258 }
259 
260 /* flush the kernel's fingerprints */
261 void
262 pfctl_clear_fingerprints(int dev, int opts)
263 {
264 	if (ioctl(dev, DIOCOSFPFLUSH))
265 		err(1, "DIOCOSFPFLUSH");
266 }
267 
268 /* flush pfctl's view of the fingerprints */
269 void
270 pfctl_flush_my_fingerprints(struct name_list *list)
271 {
272 	struct name_entry *nm;
273 
274 	while ((nm = LIST_FIRST(list)) != NULL) {
275 		LIST_REMOVE(nm, nm_entry);
276 		pfctl_flush_my_fingerprints(&nm->nm_sublist);
277 		fingerprint_count--;
278 		free(nm);
279 	}
280 	class_count = 0;
281 }
282 
283 /* Fetch the active fingerprints from the kernel */
284 int
285 pfctl_load_fingerprints(int dev, int opts)
286 {
287 	struct pf_osfp_ioctl io;
288 	int i;
289 
290 	pfctl_flush_my_fingerprints(&classes);
291 
292 	for (i = 0; i >= 0; i++) {
293 		memset(&io, 0, sizeof(io));
294 		io.fp_getnum = i;
295 		if (ioctl(dev, DIOCOSFPGET, &io)) {
296 			if (errno == EBUSY)
297 				break;
298 			warn("DIOCOSFPGET");
299 			return (1);
300 		}
301 		import_fingerprint(&io);
302 	}
303 	return (0);
304 }
305 
306 /* List the fingerprints */
307 void
308 pfctl_show_fingerprints(int opts)
309 {
310 	printf("Passive OS Fingerprints:\n");
311 	printf("\tClass\tVersion\tSubtype(subversion)\n");
312 	printf("\t-----\t-------\t-------------------\n");
313 	sort_name_list(opts, &classes);
314 	print_name_list(opts, &classes, "\t");
315 }
316 
317 /* Lookup a fingerprint */
318 pf_osfp_t
319 pfctl_get_fingerprint(const char *name)
320 {
321 	struct name_entry *nm, *class_nm, *version_nm, *subtype_nm;
322 	pf_osfp_t ret = PF_OSFP_NOMATCH;
323 	int class, version, subtype;
324 	int unp_class, unp_version, unp_subtype;
325 	int wr_len, version_len, subtype_len;
326 	char *ptr, *wr_name;
327 
328 	if (strcasecmp(name, "unknown") == 0)
329 		return (PF_OSFP_UNKNOWN);
330 
331 	/* Try most likely no version and no subtype */
332 	if ((nm = lookup_name_list(&classes, name))) {
333 		class = nm->nm_num;
334 		version = PF_OSFP_ANY;
335 		subtype = PF_OSFP_ANY;
336 		goto found;
337 	} else {
338 
339 		/* Chop it up into class/version/subtype */
340 
341 		if ((wr_name = strdup(name)) == NULL)
342 			err(1, "malloc");
343 		if ((ptr = strchr(wr_name, ' ')) == NULL) {
344 			free(wr_name);
345 			return (PF_OSFP_NOMATCH);
346 		}
347 		*ptr++ = '\0';
348 
349 		/* The class is easy to find since it is delimited by a space */
350 		if ((class_nm = lookup_name_list(&classes, wr_name)) == NULL) {
351 			free(wr_name);
352 			return (PF_OSFP_NOMATCH);
353 		}
354 		class = class_nm->nm_num;
355 
356 		/* Try no subtype */
357 		if ((version_nm = lookup_name_list(&class_nm->nm_sublist, ptr)))
358 		{
359 			version = version_nm->nm_num;
360 			subtype = PF_OSFP_ANY;
361 			free(wr_name);
362 			goto found;
363 		}
364 
365 
366 		/*
367 		 * There must be a version and a subtype.
368 		 * We'll do some fuzzy matching to pick up things like:
369 		 *   Linux 2.2.14 (version=2.2 subtype=14)
370 		 *   FreeBSD 4.0-STABLE (version=4.0 subtype=STABLE)
371 		 *   Windows 2000 SP2	(version=2000 subtype=SP2)
372 		 */
373 #define CONNECTOR(x)	((x) == '.' || (x) == ' ' || (x) == '\t' || (x) == '-')
374 		wr_len = strlen(ptr);
375 		LIST_FOREACH(version_nm, &class_nm->nm_sublist, nm_entry) {
376 			version_len = strlen(version_nm->nm_name);
377 			if (wr_len < version_len + 2 ||
378 			    !CONNECTOR(ptr[version_len]))
379 				continue;
380 			/* first part of the string must be version */
381 			if (strncasecmp(ptr, version_nm->nm_name,
382 			    version_len))
383 				continue;
384 
385 			LIST_FOREACH(subtype_nm, &version_nm->nm_sublist,
386 			    nm_entry) {
387 				subtype_len = strlen(subtype_nm->nm_name);
388 				if (wr_len != version_len + subtype_len + 1)
389 					continue;
390 
391 				/* last part of the string must be subtype */
392 				if (strcasecmp(&ptr[version_len+1],
393 				    subtype_nm->nm_name) != 0)
394 					continue;
395 
396 				/* Found it!! */
397 				version = version_nm->nm_num;
398 				subtype = subtype_nm->nm_num;
399 				free(wr_name);
400 				goto found;
401 			}
402 		}
403 
404 		free(wr_name);
405 		return (PF_OSFP_NOMATCH);
406 	}
407 
408 found:
409 	PF_OSFP_PACK(ret, class, version, subtype);
410 	if (ret != PF_OSFP_NOMATCH) {
411 		PF_OSFP_UNPACK(ret, unp_class, unp_version, unp_subtype);
412 		if (class != unp_class) {
413 			fprintf(stderr, "warning: fingerprint table overflowed "
414 			    "classes\n");
415 			return (PF_OSFP_NOMATCH);
416 		}
417 		if (version != unp_version) {
418 			fprintf(stderr, "warning: fingerprint table overflowed "
419 			    "versions\n");
420 			return (PF_OSFP_NOMATCH);
421 		}
422 		if (subtype != unp_subtype) {
423 			fprintf(stderr, "warning: fingerprint table overflowed "
424 			    "subtypes\n");
425 			return (PF_OSFP_NOMATCH);
426 		}
427 	}
428 	if (ret == PF_OSFP_ANY) {
429 		/* should never happen */
430 		fprintf(stderr, "warning: fingerprint packed to 'any'\n");
431 		return (PF_OSFP_NOMATCH);
432 	}
433 
434 	return (ret);
435 }
436 
437 /* Lookup a fingerprint name by ID */
438 char *
439 pfctl_lookup_fingerprint(pf_osfp_t fp, char *buf, size_t len)
440 {
441 	int class, version, subtype;
442 	struct name_list *list;
443 	struct name_entry *nm;
444 
445 	u_char *class_name, *version_name, *subtype_name;
446 	class_name = version_name = subtype_name = NULL;
447 
448 	if (fp == PF_OSFP_UNKNOWN) {
449 		strlcpy(buf, "unknown", len);
450 		return (buf);
451 	}
452 	if (fp == PF_OSFP_ANY) {
453 		strlcpy(buf, "any", len);
454 		return (buf);
455 	}
456 
457 	PF_OSFP_UNPACK(fp, class, version, subtype);
458 	if (class >= (1 << _FP_CLASS_BITS) ||
459 	    version >= (1 << _FP_VERSION_BITS) ||
460 	    subtype >= (1 << _FP_SUBTYPE_BITS)) {
461 		warnx("PF_OSFP_UNPACK(0x%x) failed!!", fp);
462 		strlcpy(buf, "nomatch", len);
463 		return (buf);
464 	}
465 
466 	LIST_FOREACH(nm, &classes, nm_entry) {
467 		if (nm->nm_num == class) {
468 			class_name = nm->nm_name;
469 			if (version == PF_OSFP_ANY)
470 				goto found;
471 			list = &nm->nm_sublist;
472 			LIST_FOREACH(nm, list, nm_entry) {
473 				if (nm->nm_num == version) {
474 					version_name = nm->nm_name;
475 					if (subtype == PF_OSFP_ANY)
476 						goto found;
477 					list = &nm->nm_sublist;
478 					LIST_FOREACH(nm, list, nm_entry) {
479 						if (nm->nm_num == subtype) {
480 							subtype_name =
481 							    nm->nm_name;
482 							goto found;
483 						}
484 					} /* foreach subtype */
485 					strlcpy(buf, "nomatch", len);
486 					return (buf);
487 				}
488 			} /* foreach version */
489 			strlcpy(buf, "nomatch", len);
490 			return (buf);
491 		}
492 	} /* foreach class */
493 
494 	strlcpy(buf, "nomatch", len);
495 	return (buf);
496 
497 found:
498 	snprintf(buf, len, "%s", class_name);
499 	if (version_name) {
500 		strlcat(buf, " ", len);
501 		strlcat(buf, version_name, len);
502 		if (subtype_name) {
503 			if (strchr(version_name, ' '))
504 				strlcat(buf, " ", len);
505 			else if (strchr(version_name, '.') &&
506 			    isdigit(*subtype_name))
507 				strlcat(buf, ".", len);
508 			else
509 				strlcat(buf, " ", len);
510 			strlcat(buf, subtype_name, len);
511 		}
512 	}
513 	return (buf);
514 }
515 
516 /* lookup a name in a list */
517 struct name_entry *
518 lookup_name_list(struct name_list *list, const char *name)
519 {
520 	struct name_entry *nm;
521 	LIST_FOREACH(nm, list, nm_entry)
522 		if (strcasecmp(name, nm->nm_name) == 0)
523 			return (nm);
524 
525 	return (NULL);
526 }
527 
528 
529 void
530 add_fingerprint(int dev, int opts, struct pf_osfp_ioctl *fp)
531 {
532 	struct pf_osfp_ioctl fptmp;
533 	struct name_entry *nm_class, *nm_version, *nm_subtype;
534 	int class, version, subtype;
535 
536 /* We expand #-# or #.#-#.# version/subtypes into multiple fingerprints */
537 #define EXPAND(field) do {						\
538 	int _dot = -1, _start = -1, _end = -1, _i = 0;			\
539 	/* pick major version out of #.# */				\
540 	if (isdigit(fp->field[_i]) && fp->field[_i+1] == '.') {		\
541 		_dot = fp->field[_i] - '0';				\
542 		_i += 2;						\
543 	}								\
544 	if (isdigit(fp->field[_i]))					\
545 		_start = fp->field[_i++] - '0';				\
546 	else								\
547 		break;							\
548 	if (isdigit(fp->field[_i]))					\
549 		_start = (_start * 10) + fp->field[_i++] - '0';		\
550 	if (fp->field[_i++] != '-')					\
551 		break;							\
552 	if (isdigit(fp->field[_i]) && fp->field[_i+1] == '.' &&		\
553 	    fp->field[_i] - '0' == _dot)				\
554 		_i += 2;						\
555 	else if (_dot != -1)						\
556 		break;							\
557 	if (isdigit(fp->field[_i]))					\
558 		_end = fp->field[_i++] - '0';				\
559 	else								\
560 		break;							\
561 	if (isdigit(fp->field[_i]))					\
562 		_end = (_end * 10) + fp->field[_i++] - '0';		\
563 	if (isdigit(fp->field[_i]))					\
564 		_end = (_end * 10) + fp->field[_i++] - '0';		\
565 	if (fp->field[_i] != '\0')					\
566 		break;							\
567 	memcpy(&fptmp, fp, sizeof(fptmp));				\
568 	for (;_start <= _end; _start++) {				\
569 		memset(fptmp.field, 0, sizeof(fptmp.field));		\
570 		fptmp.fp_os.fp_enflags |= PF_OSFP_EXPANDED;		\
571 		if (_dot == -1)						\
572 			snprintf(fptmp.field, sizeof(fptmp.field),	\
573 			    "%d", _start);				\
574 		    else						\
575 			snprintf(fptmp.field, sizeof(fptmp.field),	\
576 			    "%d.%d", _dot, _start);			\
577 		add_fingerprint(dev, opts, &fptmp);			\
578 	}								\
579 } while(0)
580 
581 	/* We allow "#-#" as a version or subtype and we'll expand it */
582 	EXPAND(fp_os.fp_version_nm);
583 	EXPAND(fp_os.fp_subtype_nm);
584 
585 	if (strcasecmp(fp->fp_os.fp_class_nm, "nomatch") == 0)
586 		errx(1, "fingerprint class \"nomatch\" is reserved");
587 
588 	version = PF_OSFP_ANY;
589 	subtype = PF_OSFP_ANY;
590 
591 	nm_class = fingerprint_name_entry(&classes, fp->fp_os.fp_class_nm);
592 	if (nm_class->nm_num == 0)
593 		nm_class->nm_num = ++class_count;
594 	class = nm_class->nm_num;
595 
596 	nm_version = fingerprint_name_entry(&nm_class->nm_sublist,
597 	    fp->fp_os.fp_version_nm);
598 	if (nm_version) {
599 		if (nm_version->nm_num == 0)
600 			nm_version->nm_num = ++nm_class->nm_sublist_num;
601 		version = nm_version->nm_num;
602 		nm_subtype = fingerprint_name_entry(&nm_version->nm_sublist,
603 		    fp->fp_os.fp_subtype_nm);
604 		if (nm_subtype) {
605 			if (nm_subtype->nm_num == 0)
606 				nm_subtype->nm_num =
607 				    ++nm_version->nm_sublist_num;
608 			subtype = nm_subtype->nm_num;
609 		}
610 	}
611 
612 
613 	DEBUG(fp, "\tsignature %d:%d:%d %s", class, version, subtype,
614 	    print_ioctl(fp));
615 
616 	PF_OSFP_PACK(fp->fp_os.fp_os, class, version, subtype);
617 	fingerprint_count++;
618 
619 #ifdef FAKE_PF_KERNEL
620 	/* Linked to the sys/net/pf_osfp.c.  Call pf_osfp_add() */
621 	if ((errno = pf_osfp_add(fp)))
622 #else
623 	if ((opts & PF_OPT_NOACTION) == 0 && ioctl(dev, DIOCOSFPADD, fp))
624 #endif /* FAKE_PF_KERNEL */
625 	{
626 		if (errno == EEXIST) {
627 			warn("Duplicate signature for %s %s %s",
628 				fp->fp_os.fp_class_nm,
629 				fp->fp_os.fp_version_nm,
630 				fp->fp_os.fp_subtype_nm);
631 
632 		} else {
633 			err(1, "DIOCOSFPADD");
634 		}
635 	}
636 }
637 
638 /* import a fingerprint from the kernel */
639 void
640 import_fingerprint(struct pf_osfp_ioctl *fp)
641 {
642 	struct name_entry *nm_class, *nm_version, *nm_subtype;
643 	int class, version, subtype;
644 
645 	PF_OSFP_UNPACK(fp->fp_os.fp_os, class, version, subtype);
646 
647 	nm_class = fingerprint_name_entry(&classes, fp->fp_os.fp_class_nm);
648 	if (nm_class->nm_num == 0) {
649 		nm_class->nm_num = class;
650 		class_count = MAX(class_count, class);
651 	}
652 
653 	nm_version = fingerprint_name_entry(&nm_class->nm_sublist,
654 	    fp->fp_os.fp_version_nm);
655 	if (nm_version) {
656 		if (nm_version->nm_num == 0) {
657 			nm_version->nm_num = version;
658 			nm_class->nm_sublist_num = MAX(nm_class->nm_sublist_num,
659 			    version);
660 		}
661 		nm_subtype = fingerprint_name_entry(&nm_version->nm_sublist,
662 		    fp->fp_os.fp_subtype_nm);
663 		if (nm_subtype) {
664 			if (nm_subtype->nm_num == 0) {
665 				nm_subtype->nm_num = subtype;
666 				nm_version->nm_sublist_num =
667 				    MAX(nm_version->nm_sublist_num, subtype);
668 			}
669 		}
670 	}
671 
672 
673 	fingerprint_count++;
674 	DEBUG(fp, "import signature %d:%d:%d", class, version, subtype);
675 }
676 
677 /* Find an entry for a fingerprints class/version/subtype */
678 struct name_entry *
679 fingerprint_name_entry(struct name_list *list, char *name)
680 {
681 	struct name_entry *nm_entry;
682 
683 	if (name == NULL || strlen(name) == 0)
684 		return (NULL);
685 
686 	LIST_FOREACH(nm_entry, list, nm_entry) {
687 		if (strcasecmp(nm_entry->nm_name, name) == 0) {
688 			/* We'll move this to the front of the list later */
689 			LIST_REMOVE(nm_entry, nm_entry);
690 			break;
691 		}
692 	}
693 	if (nm_entry == NULL) {
694 		nm_entry = calloc(1, sizeof(*nm_entry));
695 		if (nm_entry == NULL)
696 			err(1, "calloc");
697 		LIST_INIT(&nm_entry->nm_sublist);
698 		strlcpy(nm_entry->nm_name, name, sizeof(nm_entry->nm_name));
699 	}
700 	LIST_INSERT_HEAD(list, nm_entry, nm_entry);
701 	return (nm_entry);
702 }
703 
704 
705 void
706 print_name_list(int opts, struct name_list *nml, const char *prefix)
707 {
708 	char newprefix[32];
709 	struct name_entry *nm;
710 
711 	LIST_FOREACH(nm, nml, nm_entry) {
712 		snprintf(newprefix, sizeof(newprefix), "%s%s\t", prefix,
713 		    nm->nm_name);
714 		printf("%s\n", newprefix);
715 		print_name_list(opts, &nm->nm_sublist, newprefix);
716 	}
717 }
718 
719 void
720 sort_name_list(int opts, struct name_list *nml)
721 {
722 	struct name_list new;
723 	struct name_entry *nm, *nmsearch, *nmlast;
724 
725 	/* yes yes, it's a very slow sort.  so sue me */
726 
727 	LIST_INIT(&new);
728 
729 	while ((nm = LIST_FIRST(nml)) != NULL) {
730 		LIST_REMOVE(nm, nm_entry);
731 		nmlast = NULL;
732 		LIST_FOREACH(nmsearch, &new, nm_entry) {
733 			if (strcasecmp(nmsearch->nm_name, nm->nm_name) > 0) {
734 				LIST_INSERT_BEFORE(nmsearch, nm, nm_entry);
735 				break;
736 			}
737 			nmlast = nmsearch;
738 		}
739 		if (nmsearch == NULL) {
740 			if (nmlast)
741 				LIST_INSERT_AFTER(nmlast, nm, nm_entry);
742 			else
743 				LIST_INSERT_HEAD(&new, nm, nm_entry);
744 		}
745 
746 		sort_name_list(opts, &nm->nm_sublist);
747 	}
748 	nmlast = NULL;
749 	while ((nm = LIST_FIRST(&new)) != NULL) {
750 		LIST_REMOVE(nm, nm_entry);
751 		if (nmlast == NULL)
752 			LIST_INSERT_HEAD(nml, nm, nm_entry);
753 		else
754 			LIST_INSERT_AFTER(nmlast, nm, nm_entry);
755 		nmlast = nm;
756 	}
757 	return;
758 }
759 
760 /* parse the next integer in a formatted config file line */
761 int
762 get_int(u_char **line, size_t *len, int *var, int *mod,
763     const char *name, int flags, int max, const char *filename, int lineno)
764 {
765 	int fieldlen, i;
766 	u_char *field;
767 	long val = 0;
768 
769 	if (mod)
770 		*mod = 0;
771 	*var = 0;
772 
773 	field = get_field(line, len, &fieldlen);
774 	if (field == NULL)
775 		return (1);
776 	if (fieldlen == 0) {
777 		fprintf(stderr, "%s:%d empty %s\n", filename, lineno, name);
778 		return (1);
779 	}
780 
781 	i = 0;
782 	if ((*field == '%' || *field == 'S' || *field == 'T' || *field == '*')
783 	    && fieldlen >= 1) {
784 		switch (*field) {
785 		case 'S':
786 			if (mod && (flags & T_MSS))
787 				*mod = T_MSS;
788 			if (fieldlen == 1)
789 				return (0);
790 			break;
791 		case 'T':
792 			if (mod && (flags & T_MTU))
793 				*mod = T_MTU;
794 			if (fieldlen == 1)
795 				return (0);
796 			break;
797 		case '*':
798 			if (fieldlen != 1) {
799 				fprintf(stderr, "%s:%d long '%c' %s\n",
800 				    filename, lineno, *field, name);
801 				return (1);
802 			}
803 			if (mod && (flags & T_DC)) {
804 				*mod = T_DC;
805 				return (0);
806 			}
807 		case '%':
808 			if (mod && (flags & T_MOD))
809 				*mod = T_MOD;
810 			if (fieldlen == 1) {
811 				fprintf(stderr, "%s:%d modulus %s must have a "
812 				    "value\n", filename, lineno, name);
813 				return (1);
814 			}
815 			break;
816 		}
817 		if (mod == NULL || *mod == 0) {
818 			fprintf(stderr, "%s:%d does not allow %c' %s\n",
819 			    filename, lineno, *field, name);
820 			return (1);
821 		}
822 		i++;
823 	}
824 
825 	for (; i < fieldlen; i++) {
826 		if (field[i] < '0'  || field[i] > '9') {
827 			fprintf(stderr, "%s:%d non-digit character in %s\n",
828 			    filename, lineno, name);
829 			return (1);
830 		}
831 		val = val * 10 + field[i] - '0';
832 		if (val < 0) {
833 			fprintf(stderr, "%s:%d %s overflowed\n", filename,
834 			    lineno, name);
835 			return (1);
836 		}
837 	}
838 
839 	if (val > max) {
840 		fprintf(stderr, "%s:%d %s value %ld > %d\n", filename, lineno,
841 		    name, val, max);
842 		return (1);
843 	}
844 	*var = (int)val;
845 
846 	return (0);
847 }
848 
849 /* parse the next string in a formatted config file line */
850 int
851 get_str(u_char **line, size_t *len, char **v, const char *name, int minlen,
852     const char *filename, int lineno)
853 {
854 	int fieldlen;
855 	char *ptr;
856 
857 	ptr = get_field(line, len, &fieldlen);
858 	if (ptr == NULL)
859 		return (1);
860 	if (fieldlen < minlen) {
861 		fprintf(stderr, "%s:%d too short %s\n", filename, lineno, name);
862 		return (1);
863 	}
864 	if ((*v = malloc(fieldlen + 1)) == NULL) {
865 		perror("malloc()");
866 		return (1);
867 	}
868 	memcpy(*v, ptr, fieldlen);
869 	(*v)[fieldlen] = '\0';
870 
871 	return (0);
872 }
873 
874 /* Parse out the TCP opts */
875 int
876 get_tcpopts(const char *filename, int lineno, const u_char *tcpopts,
877     pf_tcpopts_t *packed, int *optcnt, int *mss, int *mss_mod, int *wscale,
878     int *wscale_mod, int *ts0)
879 {
880 	int i, opt;
881 
882 	*packed = 0;
883 	*optcnt = 0;
884 	*wscale = 0;
885 	*wscale_mod = T_DC;
886 	*mss = 0;
887 	*mss_mod = T_DC;
888 	*ts0 = 0;
889 	if (strcmp(tcpopts, ".") == 0)
890 		return (0);
891 
892 	for (i = 0; tcpopts[i] && *optcnt < PF_OSFP_MAX_OPTS;) {
893 		switch ((opt = toupper(tcpopts[i++]))) {
894 		case 'N':	/* FALLTHROUGH */
895 		case 'S':
896 			*packed = (*packed << PF_OSFP_TCPOPT_BITS) |
897 			    (opt == 'N' ? PF_OSFP_TCPOPT_NOP :
898 			    PF_OSFP_TCPOPT_SACK);
899 			break;
900 		case 'W':	/* FALLTHROUGH */
901 		case 'M': {
902 			int *this_mod, *this;
903 
904 			if (opt == 'W') {
905 				this = wscale;
906 				this_mod = wscale_mod;
907 			} else {
908 				this = mss;
909 				this_mod = mss_mod;
910 			}
911 			*this = 0;
912 			*this_mod = 0;
913 
914 			*packed = (*packed << PF_OSFP_TCPOPT_BITS) |
915 			    (opt == 'W' ? PF_OSFP_TCPOPT_WSCALE :
916 			    PF_OSFP_TCPOPT_MSS);
917 			if (tcpopts[i] == '*' && (tcpopts[i + 1] == '\0' ||
918 			    tcpopts[i + 1] == ',')) {
919 				*this_mod = T_DC;
920 				i++;
921 				break;
922 			}
923 
924 			if (tcpopts[i] == '%') {
925 				*this_mod = T_MOD;
926 				i++;
927 			}
928 			do {
929 				if (!isdigit(tcpopts[i])) {
930 					fprintf(stderr, "%s:%d unknown "
931 					    "character '%c' in %c TCP opt\n",
932 					    filename, lineno, tcpopts[i], opt);
933 					return (1);
934 				}
935 				*this = (*this * 10) + tcpopts[i++] - '0';
936 			} while(tcpopts[i] != ',' && tcpopts[i] != '\0');
937 			break;
938 		}
939 		case 'T':
940 			if (tcpopts[i] == '0') {
941 				*ts0 = 1;
942 				i++;
943 			}
944 			*packed = (*packed << PF_OSFP_TCPOPT_BITS) |
945 			    PF_OSFP_TCPOPT_TS;
946 			break;
947 		}
948 		(*optcnt) ++;
949 		if (tcpopts[i] == '\0')
950 			break;
951 		if (tcpopts[i] != ',') {
952 			fprintf(stderr, "%s:%d unknown option to %c TCP opt\n",
953 			    filename, lineno, opt);
954 			return (1);
955 		}
956 		i++;
957 	}
958 
959 	return (0);
960 }
961 
962 /* rip the next field ouf of a formatted config file line */
963 char *
964 get_field(u_char **line, size_t *len, int *fieldlen)
965 {
966 	char *ret, *ptr = *line;
967 	size_t plen = *len;
968 
969 
970 	while (plen && isspace((unsigned char)*ptr)) {
971 		plen--;
972 		ptr++;
973 	}
974 	ret = ptr;
975 	*fieldlen = 0;
976 
977 	for (; plen > 0 && *ptr != ':'; plen--, ptr++)
978 		(*fieldlen)++;
979 	if (plen) {
980 		*line = ptr + 1;
981 		*len = plen - 1;
982 	} else {
983 		*len = 0;
984 	}
985 	while (*fieldlen && isspace((unsigned char)ret[*fieldlen - 1]))
986 		(*fieldlen)--;
987 	return (ret);
988 }
989 
990 
991 const char *
992 print_ioctl(struct pf_osfp_ioctl *fp)
993 {
994 	static char buf[1024];
995 	char tmp[32];
996 	int i, opt;
997 
998 	*buf = '\0';
999 	if (fp->fp_flags & PF_OSFP_WSIZE_DC)
1000 		strlcat(buf, "*", sizeof(buf));
1001 	else if (fp->fp_flags & PF_OSFP_WSIZE_MSS)
1002 		strlcat(buf, "S", sizeof(buf));
1003 	else if (fp->fp_flags & PF_OSFP_WSIZE_MTU)
1004 		strlcat(buf, "T", sizeof(buf));
1005 	else {
1006 		if (fp->fp_flags & PF_OSFP_WSIZE_MOD)
1007 			strlcat(buf, "%", sizeof(buf));
1008 		snprintf(tmp, sizeof(tmp), "%d", fp->fp_wsize);
1009 		strlcat(buf, tmp, sizeof(buf));
1010 	}
1011 	strlcat(buf, ":", sizeof(buf));
1012 
1013 	snprintf(tmp, sizeof(tmp), "%d", fp->fp_ttl);
1014 	strlcat(buf, tmp, sizeof(buf));
1015 	strlcat(buf, ":", sizeof(buf));
1016 
1017 	if (fp->fp_flags & PF_OSFP_DF)
1018 		strlcat(buf, "1", sizeof(buf));
1019 	else
1020 		strlcat(buf, "0", sizeof(buf));
1021 	strlcat(buf, ":", sizeof(buf));
1022 
1023 	if (fp->fp_flags & PF_OSFP_PSIZE_DC)
1024 		strlcat(buf, "*", sizeof(buf));
1025 	else {
1026 		if (fp->fp_flags & PF_OSFP_PSIZE_MOD)
1027 			strlcat(buf, "%", sizeof(buf));
1028 		snprintf(tmp, sizeof(tmp), "%d", fp->fp_psize);
1029 		strlcat(buf, tmp, sizeof(buf));
1030 	}
1031 	strlcat(buf, ":", sizeof(buf));
1032 
1033 	if (fp->fp_optcnt == 0)
1034 		strlcat(buf, ".", sizeof(buf));
1035 	for (i = fp->fp_optcnt - 1; i >= 0; i--) {
1036 		opt = fp->fp_tcpopts >> (i * PF_OSFP_TCPOPT_BITS);
1037 		opt &= (1 << PF_OSFP_TCPOPT_BITS) - 1;
1038 		switch (opt) {
1039 		case PF_OSFP_TCPOPT_NOP:
1040 			strlcat(buf, "N", sizeof(buf));
1041 			break;
1042 		case PF_OSFP_TCPOPT_SACK:
1043 			strlcat(buf, "S", sizeof(buf));
1044 			break;
1045 		case PF_OSFP_TCPOPT_TS:
1046 			strlcat(buf, "T", sizeof(buf));
1047 			if (fp->fp_flags & PF_OSFP_TS0)
1048 				strlcat(buf, "0", sizeof(buf));
1049 			break;
1050 		case PF_OSFP_TCPOPT_MSS:
1051 			strlcat(buf, "M", sizeof(buf));
1052 			if (fp->fp_flags & PF_OSFP_MSS_DC)
1053 				strlcat(buf, "*", sizeof(buf));
1054 			else {
1055 				if (fp->fp_flags & PF_OSFP_MSS_MOD)
1056 					strlcat(buf, "%", sizeof(buf));
1057 				snprintf(tmp, sizeof(tmp), "%d", fp->fp_mss);
1058 				strlcat(buf, tmp, sizeof(buf));
1059 			}
1060 			break;
1061 		case PF_OSFP_TCPOPT_WSCALE:
1062 			strlcat(buf, "W", sizeof(buf));
1063 			if (fp->fp_flags & PF_OSFP_WSCALE_DC)
1064 				strlcat(buf, "*", sizeof(buf));
1065 			else {
1066 				if (fp->fp_flags & PF_OSFP_WSCALE_MOD)
1067 					strlcat(buf, "%", sizeof(buf));
1068 				snprintf(tmp, sizeof(tmp), "%d", fp->fp_wscale);
1069 				strlcat(buf, tmp, sizeof(buf));
1070 			}
1071 			break;
1072 		}
1073 
1074 		if (i != 0)
1075 			strlcat(buf, ",", sizeof(buf));
1076 	}
1077 	strlcat(buf, ":", sizeof(buf));
1078 
1079 	strlcat(buf, fp->fp_os.fp_class_nm, sizeof(buf));
1080 	strlcat(buf, ":", sizeof(buf));
1081 	strlcat(buf, fp->fp_os.fp_version_nm, sizeof(buf));
1082 	strlcat(buf, ":", sizeof(buf));
1083 	strlcat(buf, fp->fp_os.fp_subtype_nm, sizeof(buf));
1084 	strlcat(buf, ":", sizeof(buf));
1085 
1086 	snprintf(tmp, sizeof(tmp), "TcpOpts %d 0x%llx", fp->fp_optcnt,
1087 	    (long long int)fp->fp_tcpopts);
1088 	strlcat(buf, tmp, sizeof(buf));
1089 
1090 	return (buf);
1091 }
1092