xref: /openbsd-src/usr.sbin/tcpdump/pfctl_osfp.c (revision ae3cb403620ab940fbaabb3055fac045a63d56b7)
1 /*	$OpenBSD: pfctl_osfp.c,v 1.13 2017/05/28 10:06:12 akfaew 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 /* XXX arbitrary */
85 #define MAX_FP_LINE 1024
86 
87 /* Load fingerprints from a file */
88 int
89 pfctl_file_fingerprints(int dev, int opts, const char *fp_filename)
90 {
91 	u_char buf[MAX_FP_LINE];
92 	u_char *line;
93 	size_t len;
94 	int i, lineno = 0;
95 	int window, w_mod, ttl, df, psize, p_mod, mss, mss_mod, wscale,
96 	    wscale_mod, optcnt, ts0;
97 	pf_tcpopts_t packed_tcpopts;
98 	char *class, *version, *subtype, *desc, *tcpopts;
99 	struct pf_osfp_ioctl fp;
100 
101 	pfctl_flush_my_fingerprints(&classes);
102 	class = version = subtype = desc = tcpopts = NULL;
103 
104 	if ((opts & PF_OPT_NOACTION) == 0)
105 		pfctl_clear_fingerprints(dev, opts);
106 
107 	priv_getlines(FTAB_PFOSFP);
108 	while ((len = priv_getline(buf, sizeof(buf))) > 0) {
109 		buf[len -1] = '\n';
110 		line = buf;
111 		lineno++;
112 		free(class);
113 		free(version);
114 		free(subtype);
115 		free(desc);
116 		free(tcpopts);
117 		class = version = subtype = desc = tcpopts = NULL;
118 		memset(&fp, 0, sizeof(fp));
119 
120 		/* Chop off comment */
121 		for (i = 0; i < len; i++)
122 			if (line[i] == '#') {
123 				len = i;
124 				break;
125 			}
126 		/* Chop off whitespace */
127 		while (len > 0 && isspace(line[len - 1]))
128 			len--;
129 		while (len > 0 && isspace(line[0])) {
130 			len--;
131 			line++;
132 		}
133 		if (len == 0)
134 			continue;
135 
136 #define T_DC	0x01	/* Allow don't care */
137 #define T_MSS	0x02	/* Allow MSS multiple */
138 #define T_MTU	0x04	/* Allow MTU multiple */
139 #define T_MOD	0x08	/* Allow modulus */
140 
141 #define GET_INT(v, mod, n, ty, mx) \
142 	get_int(&line, &len, &v, mod, n, ty, mx, fp_filename, lineno)
143 #define GET_STR(v, n, mn) \
144 	get_str(&line, &len, &v, n, mn, fp_filename, lineno)
145 
146 		if (GET_INT(window, &w_mod, "window size", T_DC|T_MSS|T_MTU|
147 		    T_MOD, 0xffff) ||
148 		    GET_INT(ttl, NULL, "ttl", 0, 0xff) ||
149 		    GET_INT(df, NULL, "don't fragment frag", 0, 1) ||
150 		    GET_INT(psize, &p_mod, "overall packet size", T_MOD|T_DC,
151 		    8192) ||
152 		    GET_STR(tcpopts, "TCP Options", 1) ||
153 		    GET_STR(class, "OS class", 1) ||
154 		    GET_STR(version, "OS version", 0) ||
155 		    GET_STR(subtype, "OS subtype", 0) ||
156 		    GET_STR(desc, "OS description", 2))
157 			continue;
158 		if (get_tcpopts(fp_filename, lineno, tcpopts, &packed_tcpopts,
159 		    &optcnt, &mss, &mss_mod, &wscale, &wscale_mod, &ts0))
160 			continue;
161 		if (len != 0) {
162 			fprintf(stderr, "%s:%d excess field\n", fp_filename,
163 			    lineno);
164 			continue;
165 		}
166 
167 		fp.fp_ttl = ttl;
168 		if (df)
169 			fp.fp_flags |= PF_OSFP_DF;
170 		switch (w_mod) {
171 		case 0:
172 			break;
173 		case T_DC:
174 			fp.fp_flags |= PF_OSFP_WSIZE_DC;
175 			break;
176 		case T_MSS:
177 			fp.fp_flags |= PF_OSFP_WSIZE_MSS;
178 			break;
179 		case T_MTU:
180 			fp.fp_flags |= PF_OSFP_WSIZE_MTU;
181 			break;
182 		case T_MOD:
183 			fp.fp_flags |= PF_OSFP_WSIZE_MOD;
184 			break;
185 		}
186 		fp.fp_wsize = window;
187 
188 		switch (p_mod) {
189 		case T_DC:
190 			fp.fp_flags |= PF_OSFP_PSIZE_DC;
191 			break;
192 		case T_MOD:
193 			fp.fp_flags |= PF_OSFP_PSIZE_MOD;
194 		}
195 		fp.fp_psize = psize;
196 
197 
198 		switch (wscale_mod) {
199 		case T_DC:
200 			fp.fp_flags |= PF_OSFP_WSCALE_DC;
201 			break;
202 		case T_MOD:
203 			fp.fp_flags |= PF_OSFP_WSCALE_MOD;
204 		}
205 		fp.fp_wscale = wscale;
206 
207 		switch (mss_mod) {
208 		case T_DC:
209 			fp.fp_flags |= PF_OSFP_MSS_DC;
210 			break;
211 		case T_MOD:
212 			fp.fp_flags |= PF_OSFP_MSS_MOD;
213 			break;
214 		}
215 		fp.fp_mss = mss;
216 
217 		fp.fp_tcpopts = packed_tcpopts;
218 		fp.fp_optcnt = optcnt;
219 		if (ts0)
220 			fp.fp_flags |= PF_OSFP_TS0;
221 
222 		if (class[0] == '@')
223 			fp.fp_os.fp_enflags |= PF_OSFP_GENERIC;
224 		if (class[0] == '*')
225 			fp.fp_os.fp_enflags |= PF_OSFP_NODETAIL;
226 
227 		if (class[0] == '@' || class[0] == '*')
228 			strlcpy(fp.fp_os.fp_class_nm, class + 1,
229 			    sizeof(fp.fp_os.fp_class_nm));
230 		else
231 			strlcpy(fp.fp_os.fp_class_nm, class,
232 			    sizeof(fp.fp_os.fp_class_nm));
233 		strlcpy(fp.fp_os.fp_version_nm, version,
234 		    sizeof(fp.fp_os.fp_version_nm));
235 		strlcpy(fp.fp_os.fp_subtype_nm, subtype,
236 		    sizeof(fp.fp_os.fp_subtype_nm));
237 
238 		add_fingerprint(dev, opts, &fp);
239 
240 		fp.fp_flags |= (PF_OSFP_DF | PF_OSFP_INET6);
241 		fp.fp_psize += sizeof(struct ip6_hdr) - sizeof(struct ip);
242 		add_fingerprint(dev, opts, &fp);
243 	}
244 
245 	free(class);
246 	free(version);
247 	free(subtype);
248 	free(desc);
249 	free(tcpopts);
250 
251 	if (opts & PF_OPT_VERBOSE2)
252 		printf("Loaded %d passive OS fingerprints\n",
253 		    fingerprint_count);
254 	return (0);
255 }
256 
257 /* flush the kernel's fingerprints */
258 void
259 pfctl_clear_fingerprints(int dev, int opts)
260 {
261 	if (ioctl(dev, DIOCOSFPFLUSH))
262 		err(1, "DIOCOSFPFLUSH");
263 }
264 
265 /* flush pfctl's view of the fingerprints */
266 void
267 pfctl_flush_my_fingerprints(struct name_list *list)
268 {
269 	struct name_entry *nm;
270 
271 	while ((nm = LIST_FIRST(list)) != NULL) {
272 		LIST_REMOVE(nm, nm_entry);
273 		pfctl_flush_my_fingerprints(&nm->nm_sublist);
274 		free(nm);
275 	}
276 	fingerprint_count = 0;
277 	class_count = 0;
278 }
279 
280 /* Fetch the active fingerprints from the kernel */
281 int
282 pfctl_load_fingerprints(int dev, int opts)
283 {
284 	struct pf_osfp_ioctl io;
285 	int i;
286 
287 	pfctl_flush_my_fingerprints(&classes);
288 
289 	for (i = 0; i >= 0; i++) {
290 		memset(&io, 0, sizeof(io));
291 		io.fp_getnum = i;
292 		if (ioctl(dev, DIOCOSFPGET, &io)) {
293 			if (errno == EBUSY)
294 				break;
295 			warn("DIOCOSFPGET");
296 			return (1);
297 		}
298 		import_fingerprint(&io);
299 	}
300 	return (0);
301 }
302 
303 /* List the fingerprints */
304 void
305 pfctl_show_fingerprints(int opts)
306 {
307 	printf("Passive OS Fingerprints:\n");
308 	printf("\tClass\tVersion\tSubtype(subversion)\n");
309 	printf("\t-----\t-------\t-------------------\n");
310 	sort_name_list(opts, &classes);
311 	print_name_list(opts, &classes, "\t");
312 }
313 
314 /* Lookup a fingerprint */
315 pf_osfp_t
316 pfctl_get_fingerprint(const char *name)
317 {
318 	struct name_entry *nm, *class_nm, *version_nm, *subtype_nm;
319 	pf_osfp_t ret = PF_OSFP_NOMATCH;
320 	int class, version, subtype;
321 	int unp_class, unp_version, unp_subtype;
322 	int wr_len, version_len, subtype_len;
323 	char *ptr, *wr_name;
324 
325 	if (strcasecmp(name, "unknown") == 0)
326 		return (PF_OSFP_UNKNOWN);
327 
328 	/* Try most likely no version and no subtype */
329 	if ((nm = lookup_name_list(&classes, name))) {
330 		class = nm->nm_num;
331 		version = PF_OSFP_ANY;
332 		subtype = PF_OSFP_ANY;
333 		goto found;
334 	} else {
335 
336 		/* Chop it up into class/version/subtype */
337 
338 		if ((wr_name = strdup(name)) == NULL)
339 			err(1, "malloc");
340 		if ((ptr = strchr(wr_name, ' ')) == NULL) {
341 			free(wr_name);
342 			return (PF_OSFP_NOMATCH);
343 		}
344 		*ptr++ = '\0';
345 
346 		/* The class is easy to find since it is delimited by a space */
347 		if ((class_nm = lookup_name_list(&classes, wr_name)) == NULL) {
348 			free(wr_name);
349 			return (PF_OSFP_NOMATCH);
350 		}
351 		class = class_nm->nm_num;
352 
353 		/* Try no subtype */
354 		if ((version_nm = lookup_name_list(&class_nm->nm_sublist, ptr)))
355 		{
356 			version = version_nm->nm_num;
357 			subtype = PF_OSFP_ANY;
358 			free(wr_name);
359 			goto found;
360 		}
361 
362 
363 		/*
364 		 * There must be a version and a subtype.
365 		 * We'll do some fuzzy matching to pick up things like:
366 		 *   Linux 2.2.14 (version=2.2 subtype=14)
367 		 *   FreeBSD 4.0-STABLE (version=4.0 subtype=STABLE)
368 		 *   Windows 2000 SP2	(version=2000 subtype=SP2)
369 		 */
370 #define CONNECTOR(x)	((x) == '.' || (x) == ' ' || (x) == '\t' || (x) == '-')
371 		wr_len = strlen(ptr);
372 		LIST_FOREACH(version_nm, &class_nm->nm_sublist, nm_entry) {
373 			version_len = strlen(version_nm->nm_name);
374 			if (wr_len < version_len + 2 ||
375 			    !CONNECTOR(ptr[version_len]))
376 				continue;
377 			/* first part of the string must be version */
378 			if (strncasecmp(ptr, version_nm->nm_name,
379 			    version_len))
380 				continue;
381 
382 			LIST_FOREACH(subtype_nm, &version_nm->nm_sublist,
383 			    nm_entry) {
384 				subtype_len = strlen(subtype_nm->nm_name);
385 				if (wr_len != version_len + subtype_len + 1)
386 					continue;
387 
388 				/* last part of the string must be subtype */
389 				if (strcasecmp(&ptr[version_len+1],
390 				    subtype_nm->nm_name) != 0)
391 					continue;
392 
393 				/* Found it!! */
394 				version = version_nm->nm_num;
395 				subtype = subtype_nm->nm_num;
396 				free(wr_name);
397 				goto found;
398 			}
399 		}
400 
401 		free(wr_name);
402 		return (PF_OSFP_NOMATCH);
403 	}
404 
405 found:
406 	PF_OSFP_PACK(ret, class, version, subtype);
407 	if (ret != PF_OSFP_NOMATCH) {
408 		PF_OSFP_UNPACK(ret, unp_class, unp_version, unp_subtype);
409 		if (class != unp_class) {
410 			fprintf(stderr, "warning: fingerprint table overflowed "
411 			    "classes\n");
412 			return (PF_OSFP_NOMATCH);
413 		}
414 		if (version != unp_version) {
415 			fprintf(stderr, "warning: fingerprint table overflowed "
416 			    "versions\n");
417 			return (PF_OSFP_NOMATCH);
418 		}
419 		if (subtype != unp_subtype) {
420 			fprintf(stderr, "warning: fingerprint table overflowed "
421 			    "subtypes\n");
422 			return (PF_OSFP_NOMATCH);
423 		}
424 	}
425 	if (ret == PF_OSFP_ANY) {
426 		/* should never happen */
427 		fprintf(stderr, "warning: fingerprint packed to 'any'\n");
428 		return (PF_OSFP_NOMATCH);
429 	}
430 
431 	return (ret);
432 }
433 
434 /* Lookup a fingerprint name by ID */
435 char *
436 pfctl_lookup_fingerprint(pf_osfp_t fp, char *buf, size_t len)
437 {
438 	int class, version, subtype;
439 	struct name_list *list;
440 	struct name_entry *nm;
441 
442 	u_char *class_name, *version_name, *subtype_name;
443 	class_name = version_name = subtype_name = NULL;
444 
445 	if (fp == PF_OSFP_UNKNOWN) {
446 		strlcpy(buf, "unknown", len);
447 		return (buf);
448 	}
449 	if (fp == PF_OSFP_ANY) {
450 		strlcpy(buf, "any", len);
451 		return (buf);
452 	}
453 
454 	PF_OSFP_UNPACK(fp, class, version, subtype);
455 	if (class >= (1 << _FP_CLASS_BITS) ||
456 	    version >= (1 << _FP_VERSION_BITS) ||
457 	    subtype >= (1 << _FP_SUBTYPE_BITS)) {
458 		warnx("PF_OSFP_UNPACK(0x%x) failed!!", fp);
459 		strlcpy(buf, "nomatch", len);
460 		return (buf);
461 	}
462 
463 	LIST_FOREACH(nm, &classes, nm_entry) {
464 		if (nm->nm_num == class) {
465 			class_name = nm->nm_name;
466 			if (version == PF_OSFP_ANY)
467 				goto found;
468 			list = &nm->nm_sublist;
469 			LIST_FOREACH(nm, list, nm_entry) {
470 				if (nm->nm_num == version) {
471 					version_name = nm->nm_name;
472 					if (subtype == PF_OSFP_ANY)
473 						goto found;
474 					list = &nm->nm_sublist;
475 					LIST_FOREACH(nm, list, nm_entry) {
476 						if (nm->nm_num == subtype) {
477 							subtype_name =
478 							    nm->nm_name;
479 							goto found;
480 						}
481 					} /* foreach subtype */
482 					strlcpy(buf, "nomatch", len);
483 					return (buf);
484 				}
485 			} /* foreach version */
486 			strlcpy(buf, "nomatch", len);
487 			return (buf);
488 		}
489 	} /* foreach class */
490 
491 	strlcpy(buf, "nomatch", len);
492 	return (buf);
493 
494 found:
495 	snprintf(buf, len, "%s", class_name);
496 	if (version_name) {
497 		strlcat(buf, " ", len);
498 		strlcat(buf, version_name, len);
499 		if (subtype_name) {
500 			if (strchr(version_name, ' '))
501 				strlcat(buf, " ", len);
502 			else if (strchr(version_name, '.') &&
503 			    isdigit(*subtype_name))
504 				strlcat(buf, ".", len);
505 			else
506 				strlcat(buf, " ", len);
507 			strlcat(buf, subtype_name, len);
508 		}
509 	}
510 	return (buf);
511 }
512 
513 /* lookup a name in a list */
514 struct name_entry *
515 lookup_name_list(struct name_list *list, const char *name)
516 {
517 	struct name_entry *nm;
518 	LIST_FOREACH(nm, list, nm_entry)
519 		if (strcasecmp(name, nm->nm_name) == 0)
520 			return (nm);
521 
522 	return (NULL);
523 }
524 
525 
526 void
527 add_fingerprint(int dev, int opts, struct pf_osfp_ioctl *fp)
528 {
529 	struct pf_osfp_ioctl fptmp;
530 	struct name_entry *nm_class, *nm_version, *nm_subtype;
531 	int class, version, subtype;
532 
533 /* We expand #-# or #.#-#.# version/subtypes into multiple fingerprints */
534 #define EXPAND(field) do {						\
535 	int _dot = -1, _start = -1, _end = -1, _i = 0;			\
536 	/* pick major version out of #.# */				\
537 	if (isdigit(fp->field[_i]) && fp->field[_i+1] == '.') {		\
538 		_dot = fp->field[_i] - '0';				\
539 		_i += 2;						\
540 	}								\
541 	if (isdigit(fp->field[_i]))					\
542 		_start = fp->field[_i++] - '0';				\
543 	else								\
544 		break;							\
545 	if (isdigit(fp->field[_i]))					\
546 		_start = (_start * 10) + fp->field[_i++] - '0';		\
547 	if (fp->field[_i++] != '-')					\
548 		break;							\
549 	if (isdigit(fp->field[_i]) && fp->field[_i+1] == '.' &&		\
550 	    fp->field[_i] - '0' == _dot)				\
551 		_i += 2;						\
552 	else if (_dot != -1)						\
553 		break;							\
554 	if (isdigit(fp->field[_i]))					\
555 		_end = fp->field[_i++] - '0';				\
556 	else								\
557 		break;							\
558 	if (isdigit(fp->field[_i]))					\
559 		_end = (_end * 10) + fp->field[_i++] - '0';		\
560 	if (isdigit(fp->field[_i]))					\
561 		_end = (_end * 10) + fp->field[_i++] - '0';		\
562 	if (fp->field[_i] != '\0')					\
563 		break;							\
564 	memcpy(&fptmp, fp, sizeof(fptmp));				\
565 	for (;_start <= _end; _start++) {				\
566 		memset(fptmp.field, 0, sizeof(fptmp.field));		\
567 		fptmp.fp_os.fp_enflags |= PF_OSFP_EXPANDED;		\
568 		if (_dot == -1)						\
569 			snprintf(fptmp.field, sizeof(fptmp.field),	\
570 			    "%d", _start);				\
571 		    else						\
572 			snprintf(fptmp.field, sizeof(fptmp.field),	\
573 			    "%d.%d", _dot, _start);			\
574 		add_fingerprint(dev, opts, &fptmp);			\
575 	}								\
576 } while(0)
577 
578 	/* We allow "#-#" as a version or subtype and we'll expand it */
579 	EXPAND(fp_os.fp_version_nm);
580 	EXPAND(fp_os.fp_subtype_nm);
581 
582 	if (strcasecmp(fp->fp_os.fp_class_nm, "nomatch") == 0)
583 		errx(1, "fingerprint class \"nomatch\" is reserved");
584 
585 	version = PF_OSFP_ANY;
586 	subtype = PF_OSFP_ANY;
587 
588 	nm_class = fingerprint_name_entry(&classes, fp->fp_os.fp_class_nm);
589 	if (nm_class->nm_num == 0)
590 		nm_class->nm_num = ++class_count;
591 	class = nm_class->nm_num;
592 
593 	nm_version = fingerprint_name_entry(&nm_class->nm_sublist,
594 	    fp->fp_os.fp_version_nm);
595 	if (nm_version) {
596 		if (nm_version->nm_num == 0)
597 			nm_version->nm_num = ++nm_class->nm_sublist_num;
598 		version = nm_version->nm_num;
599 		nm_subtype = fingerprint_name_entry(&nm_version->nm_sublist,
600 		    fp->fp_os.fp_subtype_nm);
601 		if (nm_subtype) {
602 			if (nm_subtype->nm_num == 0)
603 				nm_subtype->nm_num =
604 				    ++nm_version->nm_sublist_num;
605 			subtype = nm_subtype->nm_num;
606 		}
607 	}
608 
609 
610 	DEBUG(fp, "\tsignature %d:%d:%d %s", class, version, subtype,
611 	    print_ioctl(fp));
612 
613 	PF_OSFP_PACK(fp->fp_os.fp_os, class, version, subtype);
614 	fingerprint_count++;
615 
616 #ifdef FAKE_PF_KERNEL
617 	/* Linked to the sys/net/pf_osfp.c.  Call pf_osfp_add() */
618 	if ((errno = pf_osfp_add(fp)))
619 #else
620 	if ((opts & PF_OPT_NOACTION) == 0 && ioctl(dev, DIOCOSFPADD, fp))
621 #endif /* FAKE_PF_KERNEL */
622 	{
623 		if (errno == EEXIST) {
624 			warn("Duplicate signature for %s %s %s",
625 				fp->fp_os.fp_class_nm,
626 				fp->fp_os.fp_version_nm,
627 				fp->fp_os.fp_subtype_nm);
628 
629 		} else {
630 			err(1, "DIOCOSFPADD");
631 		}
632 	}
633 }
634 
635 /* import a fingerprint from the kernel */
636 void
637 import_fingerprint(struct pf_osfp_ioctl *fp)
638 {
639 	struct name_entry *nm_class, *nm_version, *nm_subtype;
640 	int class, version, subtype;
641 
642 	PF_OSFP_UNPACK(fp->fp_os.fp_os, class, version, subtype);
643 
644 	nm_class = fingerprint_name_entry(&classes, fp->fp_os.fp_class_nm);
645 	if (nm_class->nm_num == 0) {
646 		nm_class->nm_num = class;
647 		class_count = MAXIMUM(class_count, class);
648 	}
649 
650 	nm_version = fingerprint_name_entry(&nm_class->nm_sublist,
651 	    fp->fp_os.fp_version_nm);
652 	if (nm_version) {
653 		if (nm_version->nm_num == 0) {
654 			nm_version->nm_num = version;
655 			nm_class->nm_sublist_num = MAXIMUM(nm_class->nm_sublist_num,
656 			    version);
657 		}
658 		nm_subtype = fingerprint_name_entry(&nm_version->nm_sublist,
659 		    fp->fp_os.fp_subtype_nm);
660 		if (nm_subtype) {
661 			if (nm_subtype->nm_num == 0) {
662 				nm_subtype->nm_num = subtype;
663 				nm_version->nm_sublist_num =
664 				    MAXIMUM(nm_version->nm_sublist_num, subtype);
665 			}
666 		}
667 	}
668 
669 
670 	fingerprint_count++;
671 	DEBUG(fp, "import signature %d:%d:%d", class, version, subtype);
672 }
673 
674 /* Find an entry for a fingerprints class/version/subtype */
675 struct name_entry *
676 fingerprint_name_entry(struct name_list *list, char *name)
677 {
678 	struct name_entry *nm_entry;
679 
680 	if (name == NULL || strlen(name) == 0)
681 		return (NULL);
682 
683 	LIST_FOREACH(nm_entry, list, nm_entry) {
684 		if (strcasecmp(nm_entry->nm_name, name) == 0) {
685 			/* We'll move this to the front of the list later */
686 			LIST_REMOVE(nm_entry, nm_entry);
687 			break;
688 		}
689 	}
690 	if (nm_entry == NULL) {
691 		nm_entry = calloc(1, sizeof(*nm_entry));
692 		if (nm_entry == NULL)
693 			err(1, "calloc");
694 		LIST_INIT(&nm_entry->nm_sublist);
695 		strlcpy(nm_entry->nm_name, name, sizeof(nm_entry->nm_name));
696 	}
697 	LIST_INSERT_HEAD(list, nm_entry, nm_entry);
698 	return (nm_entry);
699 }
700 
701 
702 void
703 print_name_list(int opts, struct name_list *nml, const char *prefix)
704 {
705 	char newprefix[32];
706 	struct name_entry *nm;
707 
708 	LIST_FOREACH(nm, nml, nm_entry) {
709 		snprintf(newprefix, sizeof(newprefix), "%s%s\t", prefix,
710 		    nm->nm_name);
711 		printf("%s\n", newprefix);
712 		print_name_list(opts, &nm->nm_sublist, newprefix);
713 	}
714 }
715 
716 void
717 sort_name_list(int opts, struct name_list *nml)
718 {
719 	struct name_list new;
720 	struct name_entry *nm, *nmsearch, *nmlast;
721 
722 	/* yes yes, it's a very slow sort.  so sue me */
723 
724 	LIST_INIT(&new);
725 
726 	while ((nm = LIST_FIRST(nml)) != NULL) {
727 		LIST_REMOVE(nm, nm_entry);
728 		nmlast = NULL;
729 		LIST_FOREACH(nmsearch, &new, nm_entry) {
730 			if (strcasecmp(nmsearch->nm_name, nm->nm_name) > 0) {
731 				LIST_INSERT_BEFORE(nmsearch, nm, nm_entry);
732 				break;
733 			}
734 			nmlast = nmsearch;
735 		}
736 		if (nmsearch == NULL) {
737 			if (nmlast)
738 				LIST_INSERT_AFTER(nmlast, nm, nm_entry);
739 			else
740 				LIST_INSERT_HEAD(&new, nm, nm_entry);
741 		}
742 
743 		sort_name_list(opts, &nm->nm_sublist);
744 	}
745 	nmlast = NULL;
746 	while ((nm = LIST_FIRST(&new)) != NULL) {
747 		LIST_REMOVE(nm, nm_entry);
748 		if (nmlast == NULL)
749 			LIST_INSERT_HEAD(nml, nm, nm_entry);
750 		else
751 			LIST_INSERT_AFTER(nmlast, nm, nm_entry);
752 		nmlast = nm;
753 	}
754 }
755 
756 /* parse the next integer in a formatted config file line */
757 int
758 get_int(u_char **line, size_t *len, int *var, int *mod,
759     const char *name, int flags, int max, const char *filename, int lineno)
760 {
761 	int fieldlen, i;
762 	u_char *field;
763 	long val = 0;
764 
765 	if (mod)
766 		*mod = 0;
767 	*var = 0;
768 
769 	field = get_field(line, len, &fieldlen);
770 	if (field == NULL)
771 		return (1);
772 	if (fieldlen == 0) {
773 		fprintf(stderr, "%s:%d empty %s\n", filename, lineno, name);
774 		return (1);
775 	}
776 
777 	i = 0;
778 	if ((*field == '%' || *field == 'S' || *field == 'T' || *field == '*')
779 	    && fieldlen >= 1) {
780 		switch (*field) {
781 		case 'S':
782 			if (mod && (flags & T_MSS))
783 				*mod = T_MSS;
784 			if (fieldlen == 1)
785 				return (0);
786 			break;
787 		case 'T':
788 			if (mod && (flags & T_MTU))
789 				*mod = T_MTU;
790 			if (fieldlen == 1)
791 				return (0);
792 			break;
793 		case '*':
794 			if (fieldlen != 1) {
795 				fprintf(stderr, "%s:%d long '%c' %s\n",
796 				    filename, lineno, *field, name);
797 				return (1);
798 			}
799 			if (mod && (flags & T_DC)) {
800 				*mod = T_DC;
801 				return (0);
802 			}
803 		case '%':
804 			if (mod && (flags & T_MOD))
805 				*mod = T_MOD;
806 			if (fieldlen == 1) {
807 				fprintf(stderr, "%s:%d modulus %s must have a "
808 				    "value\n", filename, lineno, name);
809 				return (1);
810 			}
811 			break;
812 		}
813 		if (mod == NULL || *mod == 0) {
814 			fprintf(stderr, "%s:%d does not allow %c' %s\n",
815 			    filename, lineno, *field, name);
816 			return (1);
817 		}
818 		i++;
819 	}
820 
821 	for (; i < fieldlen; i++) {
822 		if (field[i] < '0' || field[i] > '9') {
823 			fprintf(stderr, "%s:%d non-digit character in %s\n",
824 			    filename, lineno, name);
825 			return (1);
826 		}
827 		val = val * 10 + field[i] - '0';
828 		if (val < 0) {
829 			fprintf(stderr, "%s:%d %s overflowed\n", filename,
830 			    lineno, name);
831 			return (1);
832 		}
833 	}
834 
835 	if (val > max) {
836 		fprintf(stderr, "%s:%d %s value %ld > %d\n", filename, lineno,
837 		    name, val, max);
838 		return (1);
839 	}
840 	*var = (int)val;
841 
842 	return (0);
843 }
844 
845 /* parse the next string in a formatted config file line */
846 int
847 get_str(u_char **line, size_t *len, char **v, const char *name, int minlen,
848     const char *filename, int lineno)
849 {
850 	int fieldlen;
851 	char *ptr;
852 
853 	ptr = get_field(line, len, &fieldlen);
854 	if (ptr == NULL)
855 		return (1);
856 	if (fieldlen < minlen) {
857 		fprintf(stderr, "%s:%d too short %s\n", filename, lineno, name);
858 		return (1);
859 	}
860 	if ((*v = malloc(fieldlen + 1)) == NULL) {
861 		perror("malloc()");
862 		return (1);
863 	}
864 	memcpy(*v, ptr, fieldlen);
865 	(*v)[fieldlen] = '\0';
866 
867 	return (0);
868 }
869 
870 /* Parse out the TCP opts */
871 int
872 get_tcpopts(const char *filename, int lineno, const u_char *tcpopts,
873     pf_tcpopts_t *packed, int *optcnt, int *mss, int *mss_mod, int *wscale,
874     int *wscale_mod, int *ts0)
875 {
876 	int i, opt;
877 
878 	*packed = 0;
879 	*optcnt = 0;
880 	*wscale = 0;
881 	*wscale_mod = T_DC;
882 	*mss = 0;
883 	*mss_mod = T_DC;
884 	*ts0 = 0;
885 	if (strcmp(tcpopts, ".") == 0)
886 		return (0);
887 
888 	for (i = 0; tcpopts[i] && *optcnt < PF_OSFP_MAX_OPTS;) {
889 		switch ((opt = toupper(tcpopts[i++]))) {
890 		case 'N':	/* FALLTHROUGH */
891 		case 'S':
892 			*packed = (*packed << PF_OSFP_TCPOPT_BITS) |
893 			    (opt == 'N' ? PF_OSFP_TCPOPT_NOP :
894 			    PF_OSFP_TCPOPT_SACK);
895 			break;
896 		case 'W':	/* FALLTHROUGH */
897 		case 'M': {
898 			int *this_mod, *this;
899 
900 			if (opt == 'W') {
901 				this = wscale;
902 				this_mod = wscale_mod;
903 			} else {
904 				this = mss;
905 				this_mod = mss_mod;
906 			}
907 			*this = 0;
908 			*this_mod = 0;
909 
910 			*packed = (*packed << PF_OSFP_TCPOPT_BITS) |
911 			    (opt == 'W' ? PF_OSFP_TCPOPT_WSCALE :
912 			    PF_OSFP_TCPOPT_MSS);
913 			if (tcpopts[i] == '*' && (tcpopts[i + 1] == '\0' ||
914 			    tcpopts[i + 1] == ',')) {
915 				*this_mod = T_DC;
916 				i++;
917 				break;
918 			}
919 
920 			if (tcpopts[i] == '%') {
921 				*this_mod = T_MOD;
922 				i++;
923 			}
924 			do {
925 				if (!isdigit(tcpopts[i])) {
926 					fprintf(stderr, "%s:%d unknown "
927 					    "character '%c' in %c TCP opt\n",
928 					    filename, lineno, tcpopts[i], opt);
929 					return (1);
930 				}
931 				*this = (*this * 10) + tcpopts[i++] - '0';
932 			} while(tcpopts[i] != ',' && tcpopts[i] != '\0');
933 			break;
934 		}
935 		case 'T':
936 			if (tcpopts[i] == '0') {
937 				*ts0 = 1;
938 				i++;
939 			}
940 			*packed = (*packed << PF_OSFP_TCPOPT_BITS) |
941 			    PF_OSFP_TCPOPT_TS;
942 			break;
943 		}
944 		(*optcnt) ++;
945 		if (tcpopts[i] == '\0')
946 			break;
947 		if (tcpopts[i] != ',') {
948 			fprintf(stderr, "%s:%d unknown option to %c TCP opt\n",
949 			    filename, lineno, opt);
950 			return (1);
951 		}
952 		i++;
953 	}
954 
955 	return (0);
956 }
957 
958 /* rip the next field out of a formatted config file line */
959 char *
960 get_field(u_char **line, size_t *len, int *fieldlen)
961 {
962 	char *ret, *ptr = *line;
963 	size_t plen = *len;
964 
965 
966 	while (plen && isspace((unsigned char)*ptr)) {
967 		plen--;
968 		ptr++;
969 	}
970 	ret = ptr;
971 	*fieldlen = 0;
972 
973 	for (; plen > 0 && *ptr != ':'; plen--, ptr++)
974 		(*fieldlen)++;
975 	if (plen) {
976 		*line = ptr + 1;
977 		*len = plen - 1;
978 	} else {
979 		*len = 0;
980 	}
981 	while (*fieldlen && isspace((unsigned char)ret[*fieldlen - 1]))
982 		(*fieldlen)--;
983 	return (ret);
984 }
985 
986 
987 #ifdef OSFP_DEBUG
988 const char *
989 print_ioctl(struct pf_osfp_ioctl *fp)
990 {
991 	static char buf[1024];
992 	char tmp[32];
993 	int i, opt;
994 
995 	*buf = '\0';
996 	if (fp->fp_flags & PF_OSFP_WSIZE_DC)
997 		strlcat(buf, "*", sizeof(buf));
998 	else if (fp->fp_flags & PF_OSFP_WSIZE_MSS)
999 		strlcat(buf, "S", sizeof(buf));
1000 	else if (fp->fp_flags & PF_OSFP_WSIZE_MTU)
1001 		strlcat(buf, "T", sizeof(buf));
1002 	else {
1003 		if (fp->fp_flags & PF_OSFP_WSIZE_MOD)
1004 			strlcat(buf, "%", sizeof(buf));
1005 		snprintf(tmp, sizeof(tmp), "%d", fp->fp_wsize);
1006 		strlcat(buf, tmp, sizeof(buf));
1007 	}
1008 	strlcat(buf, ":", sizeof(buf));
1009 
1010 	snprintf(tmp, sizeof(tmp), "%d", fp->fp_ttl);
1011 	strlcat(buf, tmp, sizeof(buf));
1012 	strlcat(buf, ":", sizeof(buf));
1013 
1014 	if (fp->fp_flags & PF_OSFP_DF)
1015 		strlcat(buf, "1", sizeof(buf));
1016 	else
1017 		strlcat(buf, "0", sizeof(buf));
1018 	strlcat(buf, ":", sizeof(buf));
1019 
1020 	if (fp->fp_flags & PF_OSFP_PSIZE_DC)
1021 		strlcat(buf, "*", sizeof(buf));
1022 	else {
1023 		if (fp->fp_flags & PF_OSFP_PSIZE_MOD)
1024 			strlcat(buf, "%", sizeof(buf));
1025 		snprintf(tmp, sizeof(tmp), "%d", fp->fp_psize);
1026 		strlcat(buf, tmp, sizeof(buf));
1027 	}
1028 	strlcat(buf, ":", sizeof(buf));
1029 
1030 	if (fp->fp_optcnt == 0)
1031 		strlcat(buf, ".", sizeof(buf));
1032 	for (i = fp->fp_optcnt - 1; i >= 0; i--) {
1033 		opt = fp->fp_tcpopts >> (i * PF_OSFP_TCPOPT_BITS);
1034 		opt &= (1 << PF_OSFP_TCPOPT_BITS) - 1;
1035 		switch (opt) {
1036 		case PF_OSFP_TCPOPT_NOP:
1037 			strlcat(buf, "N", sizeof(buf));
1038 			break;
1039 		case PF_OSFP_TCPOPT_SACK:
1040 			strlcat(buf, "S", sizeof(buf));
1041 			break;
1042 		case PF_OSFP_TCPOPT_TS:
1043 			strlcat(buf, "T", sizeof(buf));
1044 			if (fp->fp_flags & PF_OSFP_TS0)
1045 				strlcat(buf, "0", sizeof(buf));
1046 			break;
1047 		case PF_OSFP_TCPOPT_MSS:
1048 			strlcat(buf, "M", sizeof(buf));
1049 			if (fp->fp_flags & PF_OSFP_MSS_DC)
1050 				strlcat(buf, "*", sizeof(buf));
1051 			else {
1052 				if (fp->fp_flags & PF_OSFP_MSS_MOD)
1053 					strlcat(buf, "%", sizeof(buf));
1054 				snprintf(tmp, sizeof(tmp), "%d", fp->fp_mss);
1055 				strlcat(buf, tmp, sizeof(buf));
1056 			}
1057 			break;
1058 		case PF_OSFP_TCPOPT_WSCALE:
1059 			strlcat(buf, "W", sizeof(buf));
1060 			if (fp->fp_flags & PF_OSFP_WSCALE_DC)
1061 				strlcat(buf, "*", sizeof(buf));
1062 			else {
1063 				if (fp->fp_flags & PF_OSFP_WSCALE_MOD)
1064 					strlcat(buf, "%", sizeof(buf));
1065 				snprintf(tmp, sizeof(tmp), "%d", fp->fp_wscale);
1066 				strlcat(buf, tmp, sizeof(buf));
1067 			}
1068 			break;
1069 		}
1070 
1071 		if (i != 0)
1072 			strlcat(buf, ",", sizeof(buf));
1073 	}
1074 	strlcat(buf, ":", sizeof(buf));
1075 
1076 	strlcat(buf, fp->fp_os.fp_class_nm, sizeof(buf));
1077 	strlcat(buf, ":", sizeof(buf));
1078 	strlcat(buf, fp->fp_os.fp_version_nm, sizeof(buf));
1079 	strlcat(buf, ":", sizeof(buf));
1080 	strlcat(buf, fp->fp_os.fp_subtype_nm, sizeof(buf));
1081 	strlcat(buf, ":", sizeof(buf));
1082 
1083 	snprintf(tmp, sizeof(tmp), "TcpOpts %d 0x%llx", fp->fp_optcnt,
1084 	    (long long int)fp->fp_tcpopts);
1085 	strlcat(buf, tmp, sizeof(buf));
1086 
1087 	return (buf);
1088 }
1089 #endif
1090