xref: /freebsd/sbin/pfctl/pfctl_osfp.c (revision 162dfe766b2a62fb875a47796ffb032242ff5124)
1 /*	$OpenBSD: pfctl_osfp.c,v 1.14 2006/04/08 02:13:14 ray 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 <net/if.h>
24 #include <net/pfvar.h>
25 
26 #include <netinet/in_systm.h>
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 #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 static struct name_list classes = LIST_HEAD_INITIALIZER(&classes);
68 static int class_count;
69 static 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(char **, size_t *, int *);
75 int			 get_int(char **, size_t *, int *, int *, const char *,
76 			     int, int, const char *, int);
77 int			 get_str(char **, size_t *, char **, const char *, int,
78 			     const char *, int);
79 int			 get_tcpopts(const char *, int, const 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 /* Load fingerprints from a file */
89 int
pfctl_file_fingerprints(int dev,int opts,const char * fp_filename)90 pfctl_file_fingerprints(int dev, int opts, const char *fp_filename)
91 {
92 	FILE *in;
93 	char *line;
94 	size_t len;
95 	int i, lineno = 0;
96 	int window, w_mod, ttl, df, psize, p_mod, mss, mss_mod, wscale,
97 	    wscale_mod, optcnt, ts0;
98 	pf_tcpopts_t packed_tcpopts;
99 	char *class, *version, *subtype, *desc, *tcpopts;
100 	struct pf_osfp_ioctl fp;
101 
102 	pfctl_flush_my_fingerprints(&classes);
103 
104 	if ((in = pfctl_fopen(fp_filename, "r")) == NULL) {
105 		warn("%s", fp_filename);
106 		return (1);
107 	}
108 	class = version = subtype = desc = tcpopts = NULL;
109 
110 	if ((opts & PF_OPT_NOACTION) == 0)
111 		pfctl_clear_fingerprints(dev, opts);
112 
113 	while ((line = fgetln(in, &len)) != NULL) {
114 		lineno++;
115 		free(class);
116 		free(version);
117 		free(subtype);
118 		free(desc);
119 		free(tcpopts);
120 		class = version = subtype = desc = tcpopts = NULL;
121 		memset(&fp, 0, sizeof(fp));
122 
123 		/* Chop off comment */
124 		for (i = 0; i < len; i++)
125 			if (line[i] == '#') {
126 				len = i;
127 				break;
128 			}
129 		/* Chop off whitespace */
130 		while (len > 0 && isspace(line[len - 1]))
131 			len--;
132 		while (len > 0 && isspace(line[0])) {
133 			len--;
134 			line++;
135 		}
136 		if (len == 0)
137 			continue;
138 
139 #define T_DC	0x01	/* Allow don't care */
140 #define T_MSS	0x02	/* Allow MSS multiple */
141 #define T_MTU	0x04	/* Allow MTU multiple */
142 #define T_MOD	0x08	/* Allow modulus */
143 
144 #define GET_INT(v, mod, n, ty, mx) \
145 	get_int(&line, &len, &v, mod, n, ty, mx, fp_filename, lineno)
146 #define GET_STR(v, n, mn) \
147 	get_str(&line, &len, &v, n, mn, fp_filename, lineno)
148 
149 		if (GET_INT(window, &w_mod, "window size", T_DC|T_MSS|T_MTU|
150 		    T_MOD, 0xffff) ||
151 		    GET_INT(ttl, NULL, "ttl", 0, 0xff) ||
152 		    GET_INT(df, NULL, "don't fragment frag", 0, 1) ||
153 		    GET_INT(psize, &p_mod, "overall packet size", T_MOD|T_DC,
154 		    8192) ||
155 		    GET_STR(tcpopts, "TCP Options", 1) ||
156 		    GET_STR(class, "OS class", 1) ||
157 		    GET_STR(version, "OS version", 0) ||
158 		    GET_STR(subtype, "OS subtype", 0) ||
159 		    GET_STR(desc, "OS description", 2))
160 			continue;
161 		if (get_tcpopts(fp_filename, lineno, tcpopts, &packed_tcpopts,
162 		    &optcnt, &mss, &mss_mod, &wscale, &wscale_mod, &ts0))
163 			continue;
164 		if (len != 0) {
165 			fprintf(stderr, "%s:%d excess field\n", fp_filename,
166 			    lineno);
167 			continue;
168 		}
169 
170 		fp.fp_ttl = ttl;
171 		if (df)
172 			fp.fp_flags |= PF_OSFP_DF;
173 		switch (w_mod) {
174 		case 0:
175 			break;
176 		case T_DC:
177 			fp.fp_flags |= PF_OSFP_WSIZE_DC;
178 			break;
179 		case T_MSS:
180 			fp.fp_flags |= PF_OSFP_WSIZE_MSS;
181 			break;
182 		case T_MTU:
183 			fp.fp_flags |= PF_OSFP_WSIZE_MTU;
184 			break;
185 		case T_MOD:
186 			fp.fp_flags |= PF_OSFP_WSIZE_MOD;
187 			break;
188 		}
189 		fp.fp_wsize = window;
190 
191 		switch (p_mod) {
192 		case T_DC:
193 			fp.fp_flags |= PF_OSFP_PSIZE_DC;
194 			break;
195 		case T_MOD:
196 			fp.fp_flags |= PF_OSFP_PSIZE_MOD;
197 		}
198 		fp.fp_psize = psize;
199 
200 
201 		switch (wscale_mod) {
202 		case T_DC:
203 			fp.fp_flags |= PF_OSFP_WSCALE_DC;
204 			break;
205 		case T_MOD:
206 			fp.fp_flags |= PF_OSFP_WSCALE_MOD;
207 		}
208 		fp.fp_wscale = wscale;
209 
210 		switch (mss_mod) {
211 		case T_DC:
212 			fp.fp_flags |= PF_OSFP_MSS_DC;
213 			break;
214 		case T_MOD:
215 			fp.fp_flags |= PF_OSFP_MSS_MOD;
216 			break;
217 		}
218 		fp.fp_mss = mss;
219 
220 		fp.fp_tcpopts = packed_tcpopts;
221 		fp.fp_optcnt = optcnt;
222 		if (ts0)
223 			fp.fp_flags |= PF_OSFP_TS0;
224 
225 		if (class[0] == '@')
226 			fp.fp_os.fp_enflags |= PF_OSFP_GENERIC;
227 		if (class[0] == '*')
228 			fp.fp_os.fp_enflags |= PF_OSFP_NODETAIL;
229 
230 		if (class[0] == '@' || class[0] == '*')
231 			strlcpy(fp.fp_os.fp_class_nm, class + 1,
232 			    sizeof(fp.fp_os.fp_class_nm));
233 		else
234 			strlcpy(fp.fp_os.fp_class_nm, class,
235 			    sizeof(fp.fp_os.fp_class_nm));
236 		strlcpy(fp.fp_os.fp_version_nm, version,
237 		    sizeof(fp.fp_os.fp_version_nm));
238 		strlcpy(fp.fp_os.fp_subtype_nm, subtype,
239 		    sizeof(fp.fp_os.fp_subtype_nm));
240 
241 		add_fingerprint(dev, opts, &fp);
242 
243 		fp.fp_flags |= (PF_OSFP_DF | PF_OSFP_INET6);
244 		fp.fp_psize += sizeof(struct ip6_hdr) - sizeof(struct ip);
245 		add_fingerprint(dev, opts, &fp);
246 	}
247 
248 	free(class);
249 	free(version);
250 	free(subtype);
251 	free(desc);
252 	free(tcpopts);
253 
254 	fclose(in);
255 
256 	if (opts & PF_OPT_VERBOSE2)
257 		printf("Loaded %d passive OS fingerprints\n",
258 		    fingerprint_count);
259 	return (0);
260 }
261 
262 /* flush the kernel's fingerprints */
263 void
pfctl_clear_fingerprints(int dev,int opts)264 pfctl_clear_fingerprints(int dev, int opts)
265 {
266 	if (ioctl(dev, DIOCOSFPFLUSH))
267 		err(1, "DIOCOSFPFLUSH");
268 }
269 
270 /* flush pfctl's view of the fingerprints */
271 void
pfctl_flush_my_fingerprints(struct name_list * list)272 pfctl_flush_my_fingerprints(struct name_list *list)
273 {
274 	struct name_entry *nm;
275 
276 	while ((nm = LIST_FIRST(list)) != NULL) {
277 		LIST_REMOVE(nm, nm_entry);
278 		pfctl_flush_my_fingerprints(&nm->nm_sublist);
279 		free(nm);
280 	}
281 	fingerprint_count = 0;
282 	class_count = 0;
283 }
284 
285 /* Fetch the active fingerprints from the kernel */
286 int
pfctl_load_fingerprints(int dev,int opts)287 pfctl_load_fingerprints(int dev, int opts)
288 {
289 	struct pf_osfp_ioctl io;
290 	int i;
291 
292 	pfctl_flush_my_fingerprints(&classes);
293 
294 	for (i = 0; i >= 0; i++) {
295 		memset(&io, 0, sizeof(io));
296 		io.fp_getnum = i;
297 		if (ioctl(dev, DIOCOSFPGET, &io)) {
298 			if (errno == EBUSY)
299 				break;
300 			warn("DIOCOSFPGET");
301 			return (1);
302 		}
303 		import_fingerprint(&io);
304 	}
305 	return (0);
306 }
307 
308 /* List the fingerprints */
309 void
pfctl_show_fingerprints(int opts)310 pfctl_show_fingerprints(int opts)
311 {
312 	if (LIST_FIRST(&classes) != NULL) {
313 		if (opts & PF_OPT_SHOWALL) {
314 			pfctl_print_title("OS FINGERPRINTS:");
315 			printf("%u fingerprints loaded\n", fingerprint_count);
316 		} else {
317 			printf("Class\tVersion\tSubtype(subversion)\n");
318 			printf("-----\t-------\t-------------------\n");
319 			sort_name_list(opts, &classes);
320 			print_name_list(opts, &classes, "");
321 		}
322 	}
323 }
324 
325 /* Lookup a fingerprint */
326 pf_osfp_t
pfctl_get_fingerprint(const char * name)327 pfctl_get_fingerprint(const char *name)
328 {
329 	struct name_entry *nm, *class_nm, *version_nm, *subtype_nm;
330 	pf_osfp_t ret = PF_OSFP_NOMATCH;
331 	int class, version, subtype;
332 	int unp_class, unp_version, unp_subtype;
333 	int wr_len, version_len, subtype_len;
334 	char *ptr, *wr_name;
335 
336 	if (strcasecmp(name, "unknown") == 0)
337 		return (PF_OSFP_UNKNOWN);
338 
339 	/* Try most likely no version and no subtype */
340 	if ((nm = lookup_name_list(&classes, name))) {
341 		class = nm->nm_num;
342 		version = PF_OSFP_ANY;
343 		subtype = PF_OSFP_ANY;
344 		goto found;
345 	} else {
346 
347 		/* Chop it up into class/version/subtype */
348 
349 		if ((wr_name = strdup(name)) == NULL)
350 			err(1, "malloc");
351 		if ((ptr = strchr(wr_name, ' ')) == NULL) {
352 			free(wr_name);
353 			return (PF_OSFP_NOMATCH);
354 		}
355 		*ptr++ = '\0';
356 
357 		/* The class is easy to find since it is delimited by a space */
358 		if ((class_nm = lookup_name_list(&classes, wr_name)) == NULL) {
359 			free(wr_name);
360 			return (PF_OSFP_NOMATCH);
361 		}
362 		class = class_nm->nm_num;
363 
364 		/* Try no subtype */
365 		if ((version_nm = lookup_name_list(&class_nm->nm_sublist, ptr)))
366 		{
367 			version = version_nm->nm_num;
368 			subtype = PF_OSFP_ANY;
369 			free(wr_name);
370 			goto found;
371 		}
372 
373 
374 		/*
375 		 * There must be a version and a subtype.
376 		 * We'll do some fuzzy matching to pick up things like:
377 		 *   Linux 2.2.14 (version=2.2 subtype=14)
378 		 *   FreeBSD 4.0-STABLE (version=4.0 subtype=STABLE)
379 		 *   Windows 2000 SP2	(version=2000 subtype=SP2)
380 		 */
381 #define CONNECTOR(x)	((x) == '.' || (x) == ' ' || (x) == '\t' || (x) == '-')
382 		wr_len = strlen(ptr);
383 		LIST_FOREACH(version_nm, &class_nm->nm_sublist, nm_entry) {
384 			version_len = strlen(version_nm->nm_name);
385 			if (wr_len < version_len + 2 ||
386 			    !CONNECTOR(ptr[version_len]))
387 				continue;
388 			/* first part of the string must be version */
389 			if (strncasecmp(ptr, version_nm->nm_name,
390 			    version_len))
391 				continue;
392 
393 			LIST_FOREACH(subtype_nm, &version_nm->nm_sublist,
394 			    nm_entry) {
395 				subtype_len = strlen(subtype_nm->nm_name);
396 				if (wr_len != version_len + subtype_len + 1)
397 					continue;
398 
399 				/* last part of the string must be subtype */
400 				if (strcasecmp(&ptr[version_len+1],
401 				    subtype_nm->nm_name) != 0)
402 					continue;
403 
404 				/* Found it!! */
405 				version = version_nm->nm_num;
406 				subtype = subtype_nm->nm_num;
407 				free(wr_name);
408 				goto found;
409 			}
410 		}
411 
412 		free(wr_name);
413 		return (PF_OSFP_NOMATCH);
414 	}
415 
416 found:
417 	PF_OSFP_PACK(ret, class, version, subtype);
418 	if (ret != PF_OSFP_NOMATCH) {
419 		PF_OSFP_UNPACK(ret, unp_class, unp_version, unp_subtype);
420 		if (class != unp_class) {
421 			fprintf(stderr, "warning: fingerprint table overflowed "
422 			    "classes\n");
423 			return (PF_OSFP_NOMATCH);
424 		}
425 		if (version != unp_version) {
426 			fprintf(stderr, "warning: fingerprint table overflowed "
427 			    "versions\n");
428 			return (PF_OSFP_NOMATCH);
429 		}
430 		if (subtype != unp_subtype) {
431 			fprintf(stderr, "warning: fingerprint table overflowed "
432 			    "subtypes\n");
433 			return (PF_OSFP_NOMATCH);
434 		}
435 	}
436 	if (ret == PF_OSFP_ANY) {
437 		/* should never happen */
438 		fprintf(stderr, "warning: fingerprint packed to 'any'\n");
439 		return (PF_OSFP_NOMATCH);
440 	}
441 
442 	return (ret);
443 }
444 
445 /* Lookup a fingerprint name by ID */
446 char *
pfctl_lookup_fingerprint(pf_osfp_t fp,char * buf,size_t len)447 pfctl_lookup_fingerprint(pf_osfp_t fp, char *buf, size_t len)
448 {
449 	int class, version, subtype;
450 	struct name_list *list;
451 	struct name_entry *nm;
452 
453 	char *class_name, *version_name, *subtype_name;
454 	class_name = version_name = subtype_name = NULL;
455 
456 	if (fp == PF_OSFP_UNKNOWN) {
457 		strlcpy(buf, "unknown", len);
458 		return (buf);
459 	}
460 	if (fp == PF_OSFP_ANY) {
461 		strlcpy(buf, "any", len);
462 		return (buf);
463 	}
464 
465 	PF_OSFP_UNPACK(fp, class, version, subtype);
466 	if (class >= (1 << _FP_CLASS_BITS) ||
467 	    version >= (1 << _FP_VERSION_BITS) ||
468 	    subtype >= (1 << _FP_SUBTYPE_BITS)) {
469 		warnx("PF_OSFP_UNPACK(0x%x) failed!!", fp);
470 		strlcpy(buf, "nomatch", len);
471 		return (buf);
472 	}
473 
474 	LIST_FOREACH(nm, &classes, nm_entry) {
475 		if (nm->nm_num == class) {
476 			class_name = nm->nm_name;
477 			if (version == PF_OSFP_ANY)
478 				goto found;
479 			list = &nm->nm_sublist;
480 			LIST_FOREACH(nm, list, nm_entry) {
481 				if (nm->nm_num == version) {
482 					version_name = nm->nm_name;
483 					if (subtype == PF_OSFP_ANY)
484 						goto found;
485 					list = &nm->nm_sublist;
486 					LIST_FOREACH(nm, list, nm_entry) {
487 						if (nm->nm_num == subtype) {
488 							subtype_name =
489 							    nm->nm_name;
490 							goto found;
491 						}
492 					} /* foreach subtype */
493 					strlcpy(buf, "nomatch", len);
494 					return (buf);
495 				}
496 			} /* foreach version */
497 			strlcpy(buf, "nomatch", len);
498 			return (buf);
499 		}
500 	} /* foreach class */
501 
502 	strlcpy(buf, "nomatch", len);
503 	return (buf);
504 
505 found:
506 	snprintf(buf, len, "%s", class_name);
507 	if (version_name) {
508 		strlcat(buf, " ", len);
509 		strlcat(buf, version_name, len);
510 		if (subtype_name) {
511 			if (strchr(version_name, ' '))
512 				strlcat(buf, " ", len);
513 			else if (strchr(version_name, '.') &&
514 			    isdigit(*subtype_name))
515 				strlcat(buf, ".", len);
516 			else
517 				strlcat(buf, " ", len);
518 			strlcat(buf, subtype_name, len);
519 		}
520 	}
521 	return (buf);
522 }
523 
524 /* lookup a name in a list */
525 struct name_entry *
lookup_name_list(struct name_list * list,const char * name)526 lookup_name_list(struct name_list *list, const char *name)
527 {
528 	struct name_entry *nm;
529 	LIST_FOREACH(nm, list, nm_entry)
530 		if (strcasecmp(name, nm->nm_name) == 0)
531 			return (nm);
532 
533 	return (NULL);
534 }
535 
536 
537 void
add_fingerprint(int dev,int opts,struct pf_osfp_ioctl * fp)538 add_fingerprint(int dev, int opts, struct pf_osfp_ioctl *fp)
539 {
540 	struct pf_osfp_ioctl fptmp;
541 	struct name_entry *nm_class, *nm_version, *nm_subtype;
542 	int class, version, subtype;
543 
544 /* We expand #-# or #.#-#.# version/subtypes into multiple fingerprints */
545 #define EXPAND(field) do {						\
546 	int _dot = -1, _start = -1, _end = -1, _i = 0;			\
547 	/* pick major version out of #.# */				\
548 	if (isdigit(fp->field[_i]) && fp->field[_i+1] == '.') {		\
549 		_dot = fp->field[_i] - '0';				\
550 		_i += 2;						\
551 	}								\
552 	if (isdigit(fp->field[_i]))					\
553 		_start = fp->field[_i++] - '0';				\
554 	else								\
555 		break;							\
556 	if (isdigit(fp->field[_i]))					\
557 		_start = (_start * 10) + fp->field[_i++] - '0';		\
558 	if (fp->field[_i++] != '-')					\
559 		break;							\
560 	if (isdigit(fp->field[_i]) && fp->field[_i+1] == '.' &&		\
561 	    fp->field[_i] - '0' == _dot)				\
562 		_i += 2;						\
563 	else if (_dot != -1)						\
564 		break;							\
565 	if (isdigit(fp->field[_i]))					\
566 		_end = fp->field[_i++] - '0';				\
567 	else								\
568 		break;							\
569 	if (isdigit(fp->field[_i]))					\
570 		_end = (_end * 10) + fp->field[_i++] - '0';		\
571 	if (isdigit(fp->field[_i]))					\
572 		_end = (_end * 10) + fp->field[_i++] - '0';		\
573 	if (fp->field[_i] != '\0')					\
574 		break;							\
575 	memcpy(&fptmp, fp, sizeof(fptmp));				\
576 	for (;_start <= _end; _start++) {				\
577 		memset(fptmp.field, 0, sizeof(fptmp.field));		\
578 		fptmp.fp_os.fp_enflags |= PF_OSFP_EXPANDED;		\
579 		if (_dot == -1)						\
580 			snprintf(fptmp.field, sizeof(fptmp.field),	\
581 			    "%d", _start);				\
582 		    else						\
583 			snprintf(fptmp.field, sizeof(fptmp.field),	\
584 			    "%d.%d", _dot, _start);			\
585 		add_fingerprint(dev, opts, &fptmp);			\
586 	}								\
587 } while(0)
588 
589 	/* We allow "#-#" as a version or subtype and we'll expand it */
590 	EXPAND(fp_os.fp_version_nm);
591 	EXPAND(fp_os.fp_subtype_nm);
592 
593 	if (strcasecmp(fp->fp_os.fp_class_nm, "nomatch") == 0)
594 		errx(1, "fingerprint class \"nomatch\" is reserved");
595 
596 	version = PF_OSFP_ANY;
597 	subtype = PF_OSFP_ANY;
598 
599 	nm_class = fingerprint_name_entry(&classes, fp->fp_os.fp_class_nm);
600 	if (nm_class->nm_num == 0)
601 		nm_class->nm_num = ++class_count;
602 	class = nm_class->nm_num;
603 
604 	nm_version = fingerprint_name_entry(&nm_class->nm_sublist,
605 	    fp->fp_os.fp_version_nm);
606 	if (nm_version) {
607 		if (nm_version->nm_num == 0)
608 			nm_version->nm_num = ++nm_class->nm_sublist_num;
609 		version = nm_version->nm_num;
610 		nm_subtype = fingerprint_name_entry(&nm_version->nm_sublist,
611 		    fp->fp_os.fp_subtype_nm);
612 		if (nm_subtype) {
613 			if (nm_subtype->nm_num == 0)
614 				nm_subtype->nm_num =
615 				    ++nm_version->nm_sublist_num;
616 			subtype = nm_subtype->nm_num;
617 		}
618 	}
619 
620 
621 	DEBUG(fp, "\tsignature %d:%d:%d %s", class, version, subtype,
622 	    print_ioctl(fp));
623 
624 	PF_OSFP_PACK(fp->fp_os.fp_os, class, version, subtype);
625 	fingerprint_count++;
626 
627 #ifdef FAKE_PF_KERNEL
628 	/* Linked to the sys/net/pf_osfp.c.  Call pf_osfp_add() */
629 	if ((errno = pf_osfp_add(fp)))
630 #else
631 	if ((opts & PF_OPT_NOACTION) == 0 && ioctl(dev, DIOCOSFPADD, fp))
632 #endif /* FAKE_PF_KERNEL */
633 	{
634 		if (errno == EEXIST) {
635 			warn("Duplicate signature for %s %s %s",
636 				fp->fp_os.fp_class_nm,
637 				fp->fp_os.fp_version_nm,
638 				fp->fp_os.fp_subtype_nm);
639 
640 		} else {
641 			err(1, "DIOCOSFPADD");
642 		}
643 	}
644 }
645 
646 /* import a fingerprint from the kernel */
647 void
import_fingerprint(struct pf_osfp_ioctl * fp)648 import_fingerprint(struct pf_osfp_ioctl *fp)
649 {
650 	struct name_entry *nm_class, *nm_version, *nm_subtype;
651 	int class, version, subtype;
652 
653 	PF_OSFP_UNPACK(fp->fp_os.fp_os, class, version, subtype);
654 
655 	nm_class = fingerprint_name_entry(&classes, fp->fp_os.fp_class_nm);
656 	if (nm_class->nm_num == 0) {
657 		nm_class->nm_num = class;
658 		class_count = MAX(class_count, class);
659 	}
660 
661 	nm_version = fingerprint_name_entry(&nm_class->nm_sublist,
662 	    fp->fp_os.fp_version_nm);
663 	if (nm_version) {
664 		if (nm_version->nm_num == 0) {
665 			nm_version->nm_num = version;
666 			nm_class->nm_sublist_num = MAX(nm_class->nm_sublist_num,
667 			    version);
668 		}
669 		nm_subtype = fingerprint_name_entry(&nm_version->nm_sublist,
670 		    fp->fp_os.fp_subtype_nm);
671 		if (nm_subtype) {
672 			if (nm_subtype->nm_num == 0) {
673 				nm_subtype->nm_num = subtype;
674 				nm_version->nm_sublist_num =
675 				    MAX(nm_version->nm_sublist_num, subtype);
676 			}
677 		}
678 	}
679 
680 
681 	fingerprint_count++;
682 	DEBUG(fp, "import signature %d:%d:%d", class, version, subtype);
683 }
684 
685 /* Find an entry for a fingerprints class/version/subtype */
686 struct name_entry *
fingerprint_name_entry(struct name_list * list,char * name)687 fingerprint_name_entry(struct name_list *list, char *name)
688 {
689 	struct name_entry *nm_entry;
690 
691 	if (name == NULL || strlen(name) == 0)
692 		return (NULL);
693 
694 	LIST_FOREACH(nm_entry, list, nm_entry) {
695 		if (strcasecmp(nm_entry->nm_name, name) == 0) {
696 			/* We'll move this to the front of the list later */
697 			LIST_REMOVE(nm_entry, nm_entry);
698 			break;
699 		}
700 	}
701 	if (nm_entry == NULL) {
702 		nm_entry = calloc(1, sizeof(*nm_entry));
703 		if (nm_entry == NULL)
704 			err(1, "calloc");
705 		LIST_INIT(&nm_entry->nm_sublist);
706 		strlcpy(nm_entry->nm_name, name, sizeof(nm_entry->nm_name));
707 	}
708 	LIST_INSERT_HEAD(list, nm_entry, nm_entry);
709 	return (nm_entry);
710 }
711 
712 
713 void
print_name_list(int opts,struct name_list * nml,const char * prefix)714 print_name_list(int opts, struct name_list *nml, const char *prefix)
715 {
716 	char newprefix[32];
717 	struct name_entry *nm;
718 
719 	LIST_FOREACH(nm, nml, nm_entry) {
720 		snprintf(newprefix, sizeof(newprefix), "%s%s\t", prefix,
721 		    nm->nm_name);
722 		printf("%s\n", newprefix);
723 		print_name_list(opts, &nm->nm_sublist, newprefix);
724 	}
725 }
726 
727 void
sort_name_list(int opts,struct name_list * nml)728 sort_name_list(int opts, struct name_list *nml)
729 {
730 	struct name_list new;
731 	struct name_entry *nm, *nmsearch, *nmlast;
732 
733 	/* yes yes, it's a very slow sort.  so sue me */
734 
735 	LIST_INIT(&new);
736 
737 	while ((nm = LIST_FIRST(nml)) != NULL) {
738 		LIST_REMOVE(nm, nm_entry);
739 		nmlast = NULL;
740 		LIST_FOREACH(nmsearch, &new, nm_entry) {
741 			if (strcasecmp(nmsearch->nm_name, nm->nm_name) > 0) {
742 				LIST_INSERT_BEFORE(nmsearch, nm, nm_entry);
743 				break;
744 			}
745 			nmlast = nmsearch;
746 		}
747 		if (nmsearch == NULL) {
748 			if (nmlast)
749 				LIST_INSERT_AFTER(nmlast, nm, nm_entry);
750 			else
751 				LIST_INSERT_HEAD(&new, nm, nm_entry);
752 		}
753 
754 		sort_name_list(opts, &nm->nm_sublist);
755 	}
756 	nmlast = NULL;
757 	while ((nm = LIST_FIRST(&new)) != NULL) {
758 		LIST_REMOVE(nm, nm_entry);
759 		if (nmlast == NULL)
760 			LIST_INSERT_HEAD(nml, nm, nm_entry);
761 		else
762 			LIST_INSERT_AFTER(nmlast, nm, nm_entry);
763 		nmlast = nm;
764 	}
765 }
766 
767 /* parse the next integer in a formatted config file line */
768 int
get_int(char ** line,size_t * len,int * var,int * mod,const char * name,int flags,int max,const char * filename,int lineno)769 get_int(char **line, size_t *len, int *var, int *mod,
770     const char *name, int flags, int max, const char *filename, int lineno)
771 {
772 	int fieldlen, i;
773 	char *field;
774 	long val = 0;
775 
776 	if (mod)
777 		*mod = 0;
778 	*var = 0;
779 
780 	field = get_field(line, len, &fieldlen);
781 	if (field == NULL)
782 		return (1);
783 	if (fieldlen == 0) {
784 		fprintf(stderr, "%s:%d empty %s\n", filename, lineno, name);
785 		return (1);
786 	}
787 
788 	i = 0;
789 	if ((*field == '%' || *field == 'S' || *field == 'T' || *field == '*')
790 	    && fieldlen >= 1) {
791 		switch (*field) {
792 		case 'S':
793 			if (mod && (flags & T_MSS))
794 				*mod = T_MSS;
795 			if (fieldlen == 1)
796 				return (0);
797 			break;
798 		case 'T':
799 			if (mod && (flags & T_MTU))
800 				*mod = T_MTU;
801 			if (fieldlen == 1)
802 				return (0);
803 			break;
804 		case '*':
805 			if (fieldlen != 1) {
806 				fprintf(stderr, "%s:%d long '%c' %s\n",
807 				    filename, lineno, *field, name);
808 				return (1);
809 			}
810 			if (mod && (flags & T_DC)) {
811 				*mod = T_DC;
812 				return (0);
813 			}
814 		case '%':
815 			if (mod && (flags & T_MOD))
816 				*mod = T_MOD;
817 			if (fieldlen == 1) {
818 				fprintf(stderr, "%s:%d modulus %s must have a "
819 				    "value\n", filename, lineno, name);
820 				return (1);
821 			}
822 			break;
823 		}
824 		if (mod == NULL || *mod == 0) {
825 			fprintf(stderr, "%s:%d does not allow %c' %s\n",
826 			    filename, lineno, *field, name);
827 			return (1);
828 		}
829 		i++;
830 	}
831 
832 	for (; i < fieldlen; i++) {
833 		if (field[i] < '0' || field[i] > '9') {
834 			fprintf(stderr, "%s:%d non-digit character in %s\n",
835 			    filename, lineno, name);
836 			return (1);
837 		}
838 		val = val * 10 + field[i] - '0';
839 		if (val < 0) {
840 			fprintf(stderr, "%s:%d %s overflowed\n", filename,
841 			    lineno, name);
842 			return (1);
843 		}
844 	}
845 
846 	if (val > max) {
847 		fprintf(stderr, "%s:%d %s value %ld > %d\n", filename, lineno,
848 		    name, val, max);
849 		return (1);
850 	}
851 	*var = (int)val;
852 
853 	return (0);
854 }
855 
856 /* parse the next string in a formatted config file line */
857 int
get_str(char ** line,size_t * len,char ** v,const char * name,int minlen,const char * filename,int lineno)858 get_str(char **line, size_t *len, char **v, const char *name, int minlen,
859     const char *filename, int lineno)
860 {
861 	int fieldlen;
862 	char *ptr;
863 
864 	ptr = get_field(line, len, &fieldlen);
865 	if (ptr == NULL)
866 		return (1);
867 	if (fieldlen < minlen) {
868 		fprintf(stderr, "%s:%d too short %s\n", filename, lineno, name);
869 		return (1);
870 	}
871 	if ((*v = malloc(fieldlen + 1)) == NULL) {
872 		perror("malloc()");
873 		return (1);
874 	}
875 	memcpy(*v, ptr, fieldlen);
876 	(*v)[fieldlen] = '\0';
877 
878 	return (0);
879 }
880 
881 /* Parse out the TCP opts */
882 int
get_tcpopts(const char * filename,int lineno,const char * tcpopts,pf_tcpopts_t * packed,int * optcnt,int * mss,int * mss_mod,int * wscale,int * wscale_mod,int * ts0)883 get_tcpopts(const char *filename, int lineno, const char *tcpopts,
884     pf_tcpopts_t *packed, int *optcnt, int *mss, int *mss_mod, int *wscale,
885     int *wscale_mod, int *ts0)
886 {
887 	int i, opt;
888 
889 	*packed = 0;
890 	*optcnt = 0;
891 	*wscale = 0;
892 	*wscale_mod = T_DC;
893 	*mss = 0;
894 	*mss_mod = T_DC;
895 	*ts0 = 0;
896 	if (strcmp(tcpopts, ".") == 0)
897 		return (0);
898 
899 	for (i = 0; tcpopts[i] && *optcnt < PF_OSFP_MAX_OPTS;) {
900 		switch ((opt = toupper(tcpopts[i++]))) {
901 		case 'N':	/* FALLTHROUGH */
902 		case 'S':
903 			*packed = (*packed << PF_OSFP_TCPOPT_BITS) |
904 			    (opt == 'N' ? PF_OSFP_TCPOPT_NOP :
905 			    PF_OSFP_TCPOPT_SACK);
906 			break;
907 		case 'W':	/* FALLTHROUGH */
908 		case 'M': {
909 			int *this_mod, *this;
910 
911 			if (opt == 'W') {
912 				this = wscale;
913 				this_mod = wscale_mod;
914 			} else {
915 				this = mss;
916 				this_mod = mss_mod;
917 			}
918 			*this = 0;
919 			*this_mod = 0;
920 
921 			*packed = (*packed << PF_OSFP_TCPOPT_BITS) |
922 			    (opt == 'W' ? PF_OSFP_TCPOPT_WSCALE :
923 			    PF_OSFP_TCPOPT_MSS);
924 			if (tcpopts[i] == '*' && (tcpopts[i + 1] == '\0' ||
925 			    tcpopts[i + 1] == ',')) {
926 				*this_mod = T_DC;
927 				i++;
928 				break;
929 			}
930 
931 			if (tcpopts[i] == '%') {
932 				*this_mod = T_MOD;
933 				i++;
934 			}
935 			do {
936 				if (!isdigit(tcpopts[i])) {
937 					fprintf(stderr, "%s:%d unknown "
938 					    "character '%c' in %c TCP opt\n",
939 					    filename, lineno, tcpopts[i], opt);
940 					return (1);
941 				}
942 				*this = (*this * 10) + tcpopts[i++] - '0';
943 			} while(tcpopts[i] != ',' && tcpopts[i] != '\0');
944 			break;
945 		}
946 		case 'T':
947 			if (tcpopts[i] == '0') {
948 				*ts0 = 1;
949 				i++;
950 			}
951 			*packed = (*packed << PF_OSFP_TCPOPT_BITS) |
952 			    PF_OSFP_TCPOPT_TS;
953 			break;
954 		}
955 		(*optcnt) ++;
956 		if (tcpopts[i] == '\0')
957 			break;
958 		if (tcpopts[i] != ',') {
959 			fprintf(stderr, "%s:%d unknown option to %c TCP opt\n",
960 			    filename, lineno, opt);
961 			return (1);
962 		}
963 		i++;
964 	}
965 
966 	return (0);
967 }
968 
969 /* rip the next field ouf of a formatted config file line */
970 char *
get_field(char ** line,size_t * len,int * fieldlen)971 get_field(char **line, size_t *len, int *fieldlen)
972 {
973 	char *ret, *ptr = *line;
974 	size_t plen = *len;
975 
976 
977 	while (plen && isspace(*ptr)) {
978 		plen--;
979 		ptr++;
980 	}
981 	ret = ptr;
982 	*fieldlen = 0;
983 
984 	for (; plen > 0 && *ptr != ':'; plen--, ptr++)
985 		(*fieldlen)++;
986 	if (plen) {
987 		*line = ptr + 1;
988 		*len = plen - 1;
989 	} else {
990 		*len = 0;
991 	}
992 	while (*fieldlen && isspace(ret[*fieldlen - 1]))
993 		(*fieldlen)--;
994 	return (ret);
995 }
996 
997 
998 const char *
print_ioctl(struct pf_osfp_ioctl * fp)999 print_ioctl(struct pf_osfp_ioctl *fp)
1000 {
1001 	static char buf[1024];
1002 	char tmp[32];
1003 	int i, opt;
1004 
1005 	*buf = '\0';
1006 	if (fp->fp_flags & PF_OSFP_WSIZE_DC)
1007 		strlcat(buf, "*", sizeof(buf));
1008 	else if (fp->fp_flags & PF_OSFP_WSIZE_MSS)
1009 		strlcat(buf, "S", sizeof(buf));
1010 	else if (fp->fp_flags & PF_OSFP_WSIZE_MTU)
1011 		strlcat(buf, "T", sizeof(buf));
1012 	else {
1013 		if (fp->fp_flags & PF_OSFP_WSIZE_MOD)
1014 			strlcat(buf, "%", sizeof(buf));
1015 		snprintf(tmp, sizeof(tmp), "%d", fp->fp_wsize);
1016 		strlcat(buf, tmp, sizeof(buf));
1017 	}
1018 	strlcat(buf, ":", sizeof(buf));
1019 
1020 	snprintf(tmp, sizeof(tmp), "%d", fp->fp_ttl);
1021 	strlcat(buf, tmp, sizeof(buf));
1022 	strlcat(buf, ":", sizeof(buf));
1023 
1024 	if (fp->fp_flags & PF_OSFP_DF)
1025 		strlcat(buf, "1", sizeof(buf));
1026 	else
1027 		strlcat(buf, "0", sizeof(buf));
1028 	strlcat(buf, ":", sizeof(buf));
1029 
1030 	if (fp->fp_flags & PF_OSFP_PSIZE_DC)
1031 		strlcat(buf, "*", sizeof(buf));
1032 	else {
1033 		if (fp->fp_flags & PF_OSFP_PSIZE_MOD)
1034 			strlcat(buf, "%", sizeof(buf));
1035 		snprintf(tmp, sizeof(tmp), "%d", fp->fp_psize);
1036 		strlcat(buf, tmp, sizeof(buf));
1037 	}
1038 	strlcat(buf, ":", sizeof(buf));
1039 
1040 	if (fp->fp_optcnt == 0)
1041 		strlcat(buf, ".", sizeof(buf));
1042 	for (i = fp->fp_optcnt - 1; i >= 0; i--) {
1043 		opt = fp->fp_tcpopts >> (i * PF_OSFP_TCPOPT_BITS);
1044 		opt &= (1 << PF_OSFP_TCPOPT_BITS) - 1;
1045 		switch (opt) {
1046 		case PF_OSFP_TCPOPT_NOP:
1047 			strlcat(buf, "N", sizeof(buf));
1048 			break;
1049 		case PF_OSFP_TCPOPT_SACK:
1050 			strlcat(buf, "S", sizeof(buf));
1051 			break;
1052 		case PF_OSFP_TCPOPT_TS:
1053 			strlcat(buf, "T", sizeof(buf));
1054 			if (fp->fp_flags & PF_OSFP_TS0)
1055 				strlcat(buf, "0", sizeof(buf));
1056 			break;
1057 		case PF_OSFP_TCPOPT_MSS:
1058 			strlcat(buf, "M", sizeof(buf));
1059 			if (fp->fp_flags & PF_OSFP_MSS_DC)
1060 				strlcat(buf, "*", sizeof(buf));
1061 			else {
1062 				if (fp->fp_flags & PF_OSFP_MSS_MOD)
1063 					strlcat(buf, "%", sizeof(buf));
1064 				snprintf(tmp, sizeof(tmp), "%d", fp->fp_mss);
1065 				strlcat(buf, tmp, sizeof(buf));
1066 			}
1067 			break;
1068 		case PF_OSFP_TCPOPT_WSCALE:
1069 			strlcat(buf, "W", sizeof(buf));
1070 			if (fp->fp_flags & PF_OSFP_WSCALE_DC)
1071 				strlcat(buf, "*", sizeof(buf));
1072 			else {
1073 				if (fp->fp_flags & PF_OSFP_WSCALE_MOD)
1074 					strlcat(buf, "%", sizeof(buf));
1075 				snprintf(tmp, sizeof(tmp), "%d", fp->fp_wscale);
1076 				strlcat(buf, tmp, sizeof(buf));
1077 			}
1078 			break;
1079 		}
1080 
1081 		if (i != 0)
1082 			strlcat(buf, ",", sizeof(buf));
1083 	}
1084 	strlcat(buf, ":", sizeof(buf));
1085 
1086 	strlcat(buf, fp->fp_os.fp_class_nm, sizeof(buf));
1087 	strlcat(buf, ":", sizeof(buf));
1088 	strlcat(buf, fp->fp_os.fp_version_nm, sizeof(buf));
1089 	strlcat(buf, ":", sizeof(buf));
1090 	strlcat(buf, fp->fp_os.fp_subtype_nm, sizeof(buf));
1091 	strlcat(buf, ":", sizeof(buf));
1092 
1093 	snprintf(tmp, sizeof(tmp), "TcpOpts %d 0x%llx", fp->fp_optcnt,
1094 	    (long long int)fp->fp_tcpopts);
1095 	strlcat(buf, tmp, sizeof(buf));
1096 
1097 	return (buf);
1098 }
1099