xref: /openbsd-src/sbin/pfctl/pfctl_osfp.c (revision f2da64fbbbf1b03f09f390ab01267c93dfd77c4c)
1 /*	$OpenBSD: pfctl_osfp.c,v 1.23 2015/12/10 17:27:00 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 <net/if.h>
25 #include <net/pfvar.h>
26 
27 #include <netinet/ip.h>
28 #include <netinet/ip6.h>
29 
30 #include <ctype.h>
31 #include <err.h>
32 #include <errno.h>
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <string.h>
36 
37 #include "pfctl_parser.h"
38 #include "pfctl.h"
39 
40 #define MAXIMUM(a, b)	(((a) > (b)) ? (a) : (b))
41 
42 #if 0
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(char **, size_t *, int *);
69 int			 get_int(char **, size_t *, int *, int *, const char *,
70 			     int, int, const char *, int);
71 int			 get_str(char **, size_t *, char **, const char *, int,
72 			     const char *, int);
73 int			 get_tcpopts(const char *, int, const char *,
74 			    pf_tcpopts_t *, int *, int *, int *, int *, int *,
75 			    int *);
76 void			 import_fingerprint(struct pf_osfp_ioctl *);
77 const char		*print_ioctl(struct pf_osfp_ioctl *);
78 void			 print_name_list(int, struct name_list *, const char *);
79 void			 sort_name_list(int, struct name_list *);
80 struct name_entry	*lookup_name_list(struct name_list *, const char *);
81 
82 /* Load fingerprints from a file */
83 int
84 pfctl_file_fingerprints(int dev, int opts, const char *fp_filename)
85 {
86 	FILE *in;
87 	char *line;
88 	size_t len;
89 	int i, lineno = 0;
90 	int window, w_mod, ttl, df, psize, p_mod, mss, mss_mod, wscale,
91 	    wscale_mod, optcnt, ts0;
92 	pf_tcpopts_t packed_tcpopts;
93 	char *class, *version, *subtype, *desc, *tcpopts;
94 	struct pf_osfp_ioctl fp;
95 
96 	pfctl_flush_my_fingerprints(&classes);
97 
98 	if ((in = pfctl_fopen(fp_filename, "r")) == NULL) {
99 		warn("%s", fp_filename);
100 		return (1);
101 	}
102 	class = version = subtype = desc = tcpopts = NULL;
103 
104 	if ((opts & PF_OPT_NOACTION) == 0)
105 		pfctl_clear_fingerprints(dev, opts);
106 
107 	while ((line = fgetln(in, &len)) != NULL) {
108 		lineno++;
109 		free(class);
110 		free(version);
111 		free(subtype);
112 		free(desc);
113 		free(tcpopts);
114 		class = version = subtype = desc = tcpopts = NULL;
115 		memset(&fp, 0, sizeof(fp));
116 
117 		/* Chop off comment */
118 		for (i = 0; i < len; i++)
119 			if (line[i] == '#') {
120 				len = i;
121 				break;
122 			}
123 		/* Chop off whitespace */
124 		while (len > 0 && isspace((unsigned char)line[len - 1]))
125 			len--;
126 		while (len > 0 && isspace((unsigned char)line[0])) {
127 			len--;
128 			line++;
129 		}
130 		if (len == 0)
131 			continue;
132 
133 #define T_DC	0x01	/* Allow don't care */
134 #define T_MSS	0x02	/* Allow MSS multiple */
135 #define T_MTU	0x04	/* Allow MTU multiple */
136 #define T_MOD	0x08	/* Allow modulus */
137 
138 #define GET_INT(v, mod, n, ty, mx) \
139 	get_int(&line, &len, &v, mod, n, ty, mx, fp_filename, lineno)
140 #define GET_STR(v, n, mn) \
141 	get_str(&line, &len, &v, n, mn, fp_filename, lineno)
142 
143 		if (GET_INT(window, &w_mod, "window size", T_DC|T_MSS|T_MTU|
144 		    T_MOD, 0xffff) ||
145 		    GET_INT(ttl, NULL, "ttl", 0, 0xff) ||
146 		    GET_INT(df, NULL, "don't fragment frag", 0, 1) ||
147 		    GET_INT(psize, &p_mod, "overall packet size", T_MOD|T_DC,
148 		    8192) ||
149 		    GET_STR(tcpopts, "TCP Options", 1) ||
150 		    GET_STR(class, "OS class", 1) ||
151 		    GET_STR(version, "OS version", 0) ||
152 		    GET_STR(subtype, "OS subtype", 0) ||
153 		    GET_STR(desc, "OS description", 2))
154 			continue;
155 		if (get_tcpopts(fp_filename, lineno, tcpopts, &packed_tcpopts,
156 		    &optcnt, &mss, &mss_mod, &wscale, &wscale_mod, &ts0))
157 			continue;
158 		if (len != 0) {
159 			fprintf(stderr, "%s:%d excess field\n", fp_filename,
160 			    lineno);
161 			continue;
162 		}
163 
164 		fp.fp_ttl = ttl;
165 		if (df)
166 			fp.fp_flags |= PF_OSFP_DF;
167 		switch (w_mod) {
168 		case 0:
169 			break;
170 		case T_DC:
171 			fp.fp_flags |= PF_OSFP_WSIZE_DC;
172 			break;
173 		case T_MSS:
174 			fp.fp_flags |= PF_OSFP_WSIZE_MSS;
175 			break;
176 		case T_MTU:
177 			fp.fp_flags |= PF_OSFP_WSIZE_MTU;
178 			break;
179 		case T_MOD:
180 			fp.fp_flags |= PF_OSFP_WSIZE_MOD;
181 			break;
182 		}
183 		fp.fp_wsize = window;
184 
185 		switch (p_mod) {
186 		case T_DC:
187 			fp.fp_flags |= PF_OSFP_PSIZE_DC;
188 			break;
189 		case T_MOD:
190 			fp.fp_flags |= PF_OSFP_PSIZE_MOD;
191 		}
192 		fp.fp_psize = psize;
193 
194 
195 		switch (wscale_mod) {
196 		case T_DC:
197 			fp.fp_flags |= PF_OSFP_WSCALE_DC;
198 			break;
199 		case T_MOD:
200 			fp.fp_flags |= PF_OSFP_WSCALE_MOD;
201 		}
202 		fp.fp_wscale = wscale;
203 
204 		switch (mss_mod) {
205 		case T_DC:
206 			fp.fp_flags |= PF_OSFP_MSS_DC;
207 			break;
208 		case T_MOD:
209 			fp.fp_flags |= PF_OSFP_MSS_MOD;
210 			break;
211 		}
212 		fp.fp_mss = mss;
213 
214 		fp.fp_tcpopts = packed_tcpopts;
215 		fp.fp_optcnt = optcnt;
216 		if (ts0)
217 			fp.fp_flags |= PF_OSFP_TS0;
218 
219 		if (class[0] == '@')
220 			fp.fp_os.fp_enflags |= PF_OSFP_GENERIC;
221 		if (class[0] == '*')
222 			fp.fp_os.fp_enflags |= PF_OSFP_NODETAIL;
223 
224 		if (class[0] == '@' || class[0] == '*')
225 			strlcpy(fp.fp_os.fp_class_nm, class + 1,
226 			    sizeof(fp.fp_os.fp_class_nm));
227 		else
228 			strlcpy(fp.fp_os.fp_class_nm, class,
229 			    sizeof(fp.fp_os.fp_class_nm));
230 		strlcpy(fp.fp_os.fp_version_nm, version,
231 		    sizeof(fp.fp_os.fp_version_nm));
232 		strlcpy(fp.fp_os.fp_subtype_nm, subtype,
233 		    sizeof(fp.fp_os.fp_subtype_nm));
234 
235 		add_fingerprint(dev, opts, &fp);
236 
237 		fp.fp_flags |= (PF_OSFP_DF | PF_OSFP_INET6);
238 		fp.fp_psize += sizeof(struct ip6_hdr) - sizeof(struct ip);
239 		add_fingerprint(dev, opts, &fp);
240 	}
241 
242 	free(class);
243 	free(version);
244 	free(subtype);
245 	free(desc);
246 	free(tcpopts);
247 
248 	fclose(in);
249 
250 	if (opts & PF_OPT_VERBOSE2)
251 		printf("Loaded %d passive OS fingerprints\n",
252 		    fingerprint_count);
253 	return (0);
254 }
255 
256 /* flush the kernel's fingerprints */
257 void
258 pfctl_clear_fingerprints(int dev, int opts)
259 {
260 	if (ioctl(dev, DIOCOSFPFLUSH))
261 		err(1, "DIOCOSFPFLUSH");
262 }
263 
264 /* flush pfctl's view of the fingerprints */
265 void
266 pfctl_flush_my_fingerprints(struct name_list *list)
267 {
268 	struct name_entry *nm;
269 
270 	while ((nm = LIST_FIRST(list)) != NULL) {
271 		LIST_REMOVE(nm, nm_entry);
272 		pfctl_flush_my_fingerprints(&nm->nm_sublist);
273 		free(nm);
274 	}
275 	fingerprint_count = 0;
276 	class_count = 0;
277 }
278 
279 /* Fetch the active fingerprints from the kernel */
280 int
281 pfctl_load_fingerprints(int dev, int opts)
282 {
283 	struct pf_osfp_ioctl io;
284 	int i;
285 
286 	pfctl_flush_my_fingerprints(&classes);
287 
288 	for (i = 0; i >= 0; i++) {
289 		memset(&io, 0, sizeof(io));
290 		io.fp_getnum = i;
291 		if (ioctl(dev, DIOCOSFPGET, &io)) {
292 			if (errno == EBUSY)
293 				break;
294 			warn("DIOCOSFPGET");
295 			return (1);
296 		}
297 		import_fingerprint(&io);
298 	}
299 	return (0);
300 }
301 
302 /* List the fingerprints */
303 void
304 pfctl_show_fingerprints(int opts)
305 {
306 	if (LIST_FIRST(&classes) != NULL) {
307 		if (opts & PF_OPT_SHOWALL) {
308 			pfctl_print_title("OS FINGERPRINTS:");
309 			printf("%u fingerprints loaded\n", fingerprint_count);
310 		} else {
311 			printf("Class\tVersion\tSubtype(subversion)\n");
312 			printf("-----\t-------\t-------------------\n");
313 			sort_name_list(opts, &classes);
314 			print_name_list(opts, &classes, "");
315 		}
316 	}
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 	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((unsigned char)*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((unsigned char)fp->field[_i]) &&			\
543 	    fp->field[_i+1] == '.') {					\
544 		_dot = fp->field[_i] - '0';				\
545 		_i += 2;						\
546 	}								\
547 	if (isdigit((unsigned char)fp->field[_i]))			\
548 		_start = fp->field[_i++] - '0';				\
549 	else								\
550 		break;							\
551 	if (isdigit((unsigned char)fp->field[_i]))			\
552 		_start = (_start * 10) + fp->field[_i++] - '0';		\
553 	if (fp->field[_i++] != '-')					\
554 		break;							\
555 	if (isdigit((unsigned char)fp->field[_i]) &&			\
556 	    fp->field[_i+1] == '.' && fp->field[_i] - '0' == _dot)	\
557 		_i += 2;						\
558 	else if (_dot != -1)						\
559 		break;							\
560 	if (isdigit((unsigned char)fp->field[_i]))			\
561 		_end = fp->field[_i++] - '0';				\
562 	else								\
563 		break;							\
564 	if (isdigit((unsigned char)fp->field[_i]))			\
565 		_end = (_end * 10) + fp->field[_i++] - '0';		\
566 	if (isdigit((unsigned char)fp->field[_i]))			\
567 		_end = (_end * 10) + fp->field[_i++] - '0';		\
568 	if (fp->field[_i] != '\0')					\
569 		break;							\
570 	memcpy(&fptmp, fp, sizeof(fptmp));				\
571 	for (;_start <= _end; _start++) {				\
572 		memset(fptmp.field, 0, sizeof(fptmp.field));		\
573 		fptmp.fp_os.fp_enflags |= PF_OSFP_EXPANDED;		\
574 		if (_dot == -1)						\
575 			snprintf(fptmp.field, sizeof(fptmp.field),	\
576 			    "%d", _start);				\
577 		    else						\
578 			snprintf(fptmp.field, sizeof(fptmp.field),	\
579 			    "%d.%d", _dot, _start);			\
580 		add_fingerprint(dev, opts, &fptmp);			\
581 	}								\
582 } while(0)
583 
584 	/* We allow "#-#" as a version or subtype and we'll expand it */
585 	EXPAND(fp_os.fp_version_nm);
586 	EXPAND(fp_os.fp_subtype_nm);
587 
588 	if (strcasecmp(fp->fp_os.fp_class_nm, "nomatch") == 0)
589 		errx(1, "fingerprint class \"nomatch\" is reserved");
590 
591 	version = PF_OSFP_ANY;
592 	subtype = PF_OSFP_ANY;
593 
594 	nm_class = fingerprint_name_entry(&classes, fp->fp_os.fp_class_nm);
595 	if (nm_class->nm_num == 0)
596 		nm_class->nm_num = ++class_count;
597 	class = nm_class->nm_num;
598 
599 	nm_version = fingerprint_name_entry(&nm_class->nm_sublist,
600 	    fp->fp_os.fp_version_nm);
601 	if (nm_version) {
602 		if (nm_version->nm_num == 0)
603 			nm_version->nm_num = ++nm_class->nm_sublist_num;
604 		version = nm_version->nm_num;
605 		nm_subtype = fingerprint_name_entry(&nm_version->nm_sublist,
606 		    fp->fp_os.fp_subtype_nm);
607 		if (nm_subtype) {
608 			if (nm_subtype->nm_num == 0)
609 				nm_subtype->nm_num =
610 				    ++nm_version->nm_sublist_num;
611 			subtype = nm_subtype->nm_num;
612 		}
613 	}
614 
615 
616 	DEBUG(fp, "\tsignature %d:%d:%d %s", class, version, subtype,
617 	    print_ioctl(fp));
618 
619 	PF_OSFP_PACK(fp->fp_os.fp_os, class, version, subtype);
620 	fingerprint_count++;
621 
622 #ifdef FAKE_PF_KERNEL
623 	/* Linked to the sys/net/pf_osfp.c.  Call pf_osfp_add() */
624 	if ((errno = pf_osfp_add(fp)))
625 #else
626 	if ((opts & PF_OPT_NOACTION) == 0 && ioctl(dev, DIOCOSFPADD, fp))
627 #endif /* FAKE_PF_KERNEL */
628 	{
629 		if (errno == EEXIST) {
630 			warn("Duplicate signature for %s %s %s",
631 				fp->fp_os.fp_class_nm,
632 				fp->fp_os.fp_version_nm,
633 				fp->fp_os.fp_subtype_nm);
634 
635 		} else {
636 			err(1, "DIOCOSFPADD");
637 		}
638 	}
639 }
640 
641 /* import a fingerprint from the kernel */
642 void
643 import_fingerprint(struct pf_osfp_ioctl *fp)
644 {
645 	struct name_entry *nm_class, *nm_version, *nm_subtype;
646 	int class, version, subtype;
647 
648 	PF_OSFP_UNPACK(fp->fp_os.fp_os, class, version, subtype);
649 
650 	nm_class = fingerprint_name_entry(&classes, fp->fp_os.fp_class_nm);
651 	if (nm_class->nm_num == 0) {
652 		nm_class->nm_num = class;
653 		class_count = MAXIMUM(class_count, class);
654 	}
655 
656 	nm_version = fingerprint_name_entry(&nm_class->nm_sublist,
657 	    fp->fp_os.fp_version_nm);
658 	if (nm_version) {
659 		if (nm_version->nm_num == 0) {
660 			nm_version->nm_num = version;
661 			nm_class->nm_sublist_num = MAXIMUM(nm_class->nm_sublist_num,
662 			    version);
663 		}
664 		nm_subtype = fingerprint_name_entry(&nm_version->nm_sublist,
665 		    fp->fp_os.fp_subtype_nm);
666 		if (nm_subtype) {
667 			if (nm_subtype->nm_num == 0) {
668 				nm_subtype->nm_num = subtype;
669 				nm_version->nm_sublist_num =
670 				    MAXIMUM(nm_version->nm_sublist_num, subtype);
671 			}
672 		}
673 	}
674 
675 
676 	fingerprint_count++;
677 	DEBUG(fp, "import signature %d:%d:%d", class, version, subtype);
678 }
679 
680 /* Find an entry for a fingerprints class/version/subtype */
681 struct name_entry *
682 fingerprint_name_entry(struct name_list *list, char *name)
683 {
684 	struct name_entry *nm_entry;
685 
686 	if (name == NULL || strlen(name) == 0)
687 		return (NULL);
688 
689 	LIST_FOREACH(nm_entry, list, nm_entry) {
690 		if (strcasecmp(nm_entry->nm_name, name) == 0) {
691 			/* We'll move this to the front of the list later */
692 			LIST_REMOVE(nm_entry, nm_entry);
693 			break;
694 		}
695 	}
696 	if (nm_entry == NULL) {
697 		nm_entry = calloc(1, sizeof(*nm_entry));
698 		if (nm_entry == NULL)
699 			err(1, "calloc");
700 		LIST_INIT(&nm_entry->nm_sublist);
701 		strlcpy(nm_entry->nm_name, name, sizeof(nm_entry->nm_name));
702 	}
703 	LIST_INSERT_HEAD(list, nm_entry, nm_entry);
704 	return (nm_entry);
705 }
706 
707 
708 void
709 print_name_list(int opts, struct name_list *nml, const char *prefix)
710 {
711 	char newprefix[32];
712 	struct name_entry *nm;
713 
714 	LIST_FOREACH(nm, nml, nm_entry) {
715 		snprintf(newprefix, sizeof(newprefix), "%s%s\t", prefix,
716 		    nm->nm_name);
717 		printf("%s\n", newprefix);
718 		print_name_list(opts, &nm->nm_sublist, newprefix);
719 	}
720 }
721 
722 void
723 sort_name_list(int opts, struct name_list *nml)
724 {
725 	struct name_list new;
726 	struct name_entry *nm, *nmsearch, *nmlast;
727 
728 	/* yes yes, it's a very slow sort.  so sue me */
729 
730 	LIST_INIT(&new);
731 
732 	while ((nm = LIST_FIRST(nml)) != NULL) {
733 		LIST_REMOVE(nm, nm_entry);
734 		nmlast = NULL;
735 		LIST_FOREACH(nmsearch, &new, nm_entry) {
736 			if (strcasecmp(nmsearch->nm_name, nm->nm_name) > 0) {
737 				LIST_INSERT_BEFORE(nmsearch, nm, nm_entry);
738 				break;
739 			}
740 			nmlast = nmsearch;
741 		}
742 		if (nmsearch == NULL) {
743 			if (nmlast)
744 				LIST_INSERT_AFTER(nmlast, nm, nm_entry);
745 			else
746 				LIST_INSERT_HEAD(&new, nm, nm_entry);
747 		}
748 
749 		sort_name_list(opts, &nm->nm_sublist);
750 	}
751 	nmlast = NULL;
752 	while ((nm = LIST_FIRST(&new)) != NULL) {
753 		LIST_REMOVE(nm, nm_entry);
754 		if (nmlast == NULL)
755 			LIST_INSERT_HEAD(nml, nm, nm_entry);
756 		else
757 			LIST_INSERT_AFTER(nmlast, nm, nm_entry);
758 		nmlast = nm;
759 	}
760 }
761 
762 /* parse the next integer in a formatted config file line */
763 int
764 get_int(char **line, size_t *len, int *var, int *mod,
765     const char *name, int flags, int max, const char *filename, int lineno)
766 {
767 	int fieldlen, i;
768 	char *field;
769 	long val = 0;
770 
771 	if (mod)
772 		*mod = 0;
773 	*var = 0;
774 
775 	field = get_field(line, len, &fieldlen);
776 	if (field == NULL)
777 		return (1);
778 	if (fieldlen == 0) {
779 		fprintf(stderr, "%s:%d empty %s\n", filename, lineno, name);
780 		return (1);
781 	}
782 
783 	i = 0;
784 	if ((*field == '%' || *field == 'S' || *field == 'T' || *field == '*')
785 	    && fieldlen >= 1) {
786 		switch (*field) {
787 		case 'S':
788 			if (mod && (flags & T_MSS))
789 				*mod = T_MSS;
790 			if (fieldlen == 1)
791 				return (0);
792 			break;
793 		case 'T':
794 			if (mod && (flags & T_MTU))
795 				*mod = T_MTU;
796 			if (fieldlen == 1)
797 				return (0);
798 			break;
799 		case '*':
800 			if (fieldlen != 1) {
801 				fprintf(stderr, "%s:%d long '%c' %s\n",
802 				    filename, lineno, *field, name);
803 				return (1);
804 			}
805 			if (mod && (flags & T_DC)) {
806 				*mod = T_DC;
807 				return (0);
808 			}
809 		case '%':
810 			if (mod && (flags & T_MOD))
811 				*mod = T_MOD;
812 			if (fieldlen == 1) {
813 				fprintf(stderr, "%s:%d modulus %s must have a "
814 				    "value\n", filename, lineno, name);
815 				return (1);
816 			}
817 			break;
818 		}
819 		if (mod == NULL || *mod == 0) {
820 			fprintf(stderr, "%s:%d does not allow %c' %s\n",
821 			    filename, lineno, *field, name);
822 			return (1);
823 		}
824 		i++;
825 	}
826 
827 	for (; i < fieldlen; i++) {
828 		if (field[i] < '0' || field[i] > '9') {
829 			fprintf(stderr, "%s:%d non-digit character in %s\n",
830 			    filename, lineno, name);
831 			return (1);
832 		}
833 		val = val * 10 + field[i] - '0';
834 		if (val < 0) {
835 			fprintf(stderr, "%s:%d %s overflowed\n", filename,
836 			    lineno, name);
837 			return (1);
838 		}
839 	}
840 
841 	if (val > max) {
842 		fprintf(stderr, "%s:%d %s value %ld > %d\n", filename, lineno,
843 		    name, val, max);
844 		return (1);
845 	}
846 	*var = (int)val;
847 
848 	return (0);
849 }
850 
851 /* parse the next string in a formatted config file line */
852 int
853 get_str(char **line, size_t *len, char **v, const char *name, int minlen,
854     const char *filename, int lineno)
855 {
856 	int fieldlen;
857 	char *ptr;
858 
859 	ptr = get_field(line, len, &fieldlen);
860 	if (ptr == NULL)
861 		return (1);
862 	if (fieldlen < minlen) {
863 		fprintf(stderr, "%s:%d too short %s\n", filename, lineno, name);
864 		return (1);
865 	}
866 	if ((*v = malloc(fieldlen + 1)) == NULL) {
867 		perror("malloc()");
868 		return (1);
869 	}
870 	memcpy(*v, ptr, fieldlen);
871 	(*v)[fieldlen] = '\0';
872 
873 	return (0);
874 }
875 
876 /* Parse out the TCP opts */
877 int
878 get_tcpopts(const char *filename, int lineno, const char *tcpopts,
879     pf_tcpopts_t *packed, int *optcnt, int *mss, int *mss_mod, int *wscale,
880     int *wscale_mod, int *ts0)
881 {
882 	int i, opt;
883 
884 	*packed = 0;
885 	*optcnt = 0;
886 	*wscale = 0;
887 	*wscale_mod = T_DC;
888 	*mss = 0;
889 	*mss_mod = T_DC;
890 	*ts0 = 0;
891 	if (strcmp(tcpopts, ".") == 0)
892 		return (0);
893 
894 	for (i = 0; tcpopts[i] && *optcnt < PF_OSFP_MAX_OPTS;) {
895 		switch ((opt = toupper((unsigned char)tcpopts[i++]))) {
896 		case 'N':	/* FALLTHROUGH */
897 		case 'S':
898 			*packed = (*packed << PF_OSFP_TCPOPT_BITS) |
899 			    (opt == 'N' ? PF_OSFP_TCPOPT_NOP :
900 			    PF_OSFP_TCPOPT_SACK);
901 			break;
902 		case 'W':	/* FALLTHROUGH */
903 		case 'M': {
904 			int *this_mod, *this;
905 
906 			if (opt == 'W') {
907 				this = wscale;
908 				this_mod = wscale_mod;
909 			} else {
910 				this = mss;
911 				this_mod = mss_mod;
912 			}
913 			*this = 0;
914 			*this_mod = 0;
915 
916 			*packed = (*packed << PF_OSFP_TCPOPT_BITS) |
917 			    (opt == 'W' ? PF_OSFP_TCPOPT_WSCALE :
918 			    PF_OSFP_TCPOPT_MSS);
919 			if (tcpopts[i] == '*' && (tcpopts[i + 1] == '\0' ||
920 			    tcpopts[i + 1] == ',')) {
921 				*this_mod = T_DC;
922 				i++;
923 				break;
924 			}
925 
926 			if (tcpopts[i] == '%') {
927 				*this_mod = T_MOD;
928 				i++;
929 			}
930 			do {
931 				if (!isdigit((unsigned char)tcpopts[i])) {
932 					fprintf(stderr, "%s:%d unknown "
933 					    "character '%c' in %c TCP opt\n",
934 					    filename, lineno, tcpopts[i], opt);
935 					return (1);
936 				}
937 				*this = (*this * 10) + tcpopts[i++] - '0';
938 			} while(tcpopts[i] != ',' && tcpopts[i] != '\0');
939 			break;
940 		}
941 		case 'T':
942 			if (tcpopts[i] == '0') {
943 				*ts0 = 1;
944 				i++;
945 			}
946 			*packed = (*packed << PF_OSFP_TCPOPT_BITS) |
947 			    PF_OSFP_TCPOPT_TS;
948 			break;
949 		}
950 		(*optcnt) ++;
951 		if (tcpopts[i] == '\0')
952 			break;
953 		if (tcpopts[i] != ',') {
954 			fprintf(stderr, "%s:%d unknown option to %c TCP opt\n",
955 			    filename, lineno, opt);
956 			return (1);
957 		}
958 		i++;
959 	}
960 
961 	return (0);
962 }
963 
964 /* rip the next field out of a formatted config file line */
965 char *
966 get_field(char **line, size_t *len, int *fieldlen)
967 {
968 	char *ret, *ptr = *line;
969 	size_t plen = *len;
970 
971 
972 	while (plen && isspace((unsigned char)*ptr)) {
973 		plen--;
974 		ptr++;
975 	}
976 	ret = ptr;
977 	*fieldlen = 0;
978 
979 	for (; plen > 0 && *ptr != ':'; plen--, ptr++)
980 		(*fieldlen)++;
981 	if (plen) {
982 		*line = ptr + 1;
983 		*len = plen - 1;
984 	} else {
985 		*len = 0;
986 	}
987 	while (*fieldlen && isspace((unsigned char)ret[*fieldlen - 1]))
988 		(*fieldlen)--;
989 	return (ret);
990 }
991 
992 
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