xref: /freebsd/sbin/pfctl/pfctl_osfp.c (revision 32e86a82f54826f14ea381affa6674db3aa3b5ae)
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 		if (class)
116 			free(class);
117 		if (version)
118 			free(version);
119 		if (subtype)
120 			free(subtype);
121 		if (desc)
122 			free(desc);
123 		if (tcpopts)
124 			free(tcpopts);
125 		class = version = subtype = desc = tcpopts = NULL;
126 		memset(&fp, 0, sizeof(fp));
127 
128 		/* Chop off comment */
129 		for (i = 0; i < len; i++)
130 			if (line[i] == '#') {
131 				len = i;
132 				break;
133 			}
134 		/* Chop off whitespace */
135 		while (len > 0 && isspace(line[len - 1]))
136 			len--;
137 		while (len > 0 && isspace(line[0])) {
138 			len--;
139 			line++;
140 		}
141 		if (len == 0)
142 			continue;
143 
144 #define T_DC	0x01	/* Allow don't care */
145 #define T_MSS	0x02	/* Allow MSS multiple */
146 #define T_MTU	0x04	/* Allow MTU multiple */
147 #define T_MOD	0x08	/* Allow modulus */
148 
149 #define GET_INT(v, mod, n, ty, mx) \
150 	get_int(&line, &len, &v, mod, n, ty, mx, fp_filename, lineno)
151 #define GET_STR(v, n, mn) \
152 	get_str(&line, &len, &v, n, mn, fp_filename, lineno)
153 
154 		if (GET_INT(window, &w_mod, "window size", T_DC|T_MSS|T_MTU|
155 		    T_MOD, 0xffff) ||
156 		    GET_INT(ttl, NULL, "ttl", 0, 0xff) ||
157 		    GET_INT(df, NULL, "don't fragment frag", 0, 1) ||
158 		    GET_INT(psize, &p_mod, "overall packet size", T_MOD|T_DC,
159 		    8192) ||
160 		    GET_STR(tcpopts, "TCP Options", 1) ||
161 		    GET_STR(class, "OS class", 1) ||
162 		    GET_STR(version, "OS version", 0) ||
163 		    GET_STR(subtype, "OS subtype", 0) ||
164 		    GET_STR(desc, "OS description", 2))
165 			continue;
166 		if (get_tcpopts(fp_filename, lineno, tcpopts, &packed_tcpopts,
167 		    &optcnt, &mss, &mss_mod, &wscale, &wscale_mod, &ts0))
168 			continue;
169 		if (len != 0) {
170 			fprintf(stderr, "%s:%d excess field\n", fp_filename,
171 			    lineno);
172 			continue;
173 		}
174 
175 		fp.fp_ttl = ttl;
176 		if (df)
177 			fp.fp_flags |= PF_OSFP_DF;
178 		switch (w_mod) {
179 		case 0:
180 			break;
181 		case T_DC:
182 			fp.fp_flags |= PF_OSFP_WSIZE_DC;
183 			break;
184 		case T_MSS:
185 			fp.fp_flags |= PF_OSFP_WSIZE_MSS;
186 			break;
187 		case T_MTU:
188 			fp.fp_flags |= PF_OSFP_WSIZE_MTU;
189 			break;
190 		case T_MOD:
191 			fp.fp_flags |= PF_OSFP_WSIZE_MOD;
192 			break;
193 		}
194 		fp.fp_wsize = window;
195 
196 		switch (p_mod) {
197 		case T_DC:
198 			fp.fp_flags |= PF_OSFP_PSIZE_DC;
199 			break;
200 		case T_MOD:
201 			fp.fp_flags |= PF_OSFP_PSIZE_MOD;
202 		}
203 		fp.fp_psize = psize;
204 
205 
206 		switch (wscale_mod) {
207 		case T_DC:
208 			fp.fp_flags |= PF_OSFP_WSCALE_DC;
209 			break;
210 		case T_MOD:
211 			fp.fp_flags |= PF_OSFP_WSCALE_MOD;
212 		}
213 		fp.fp_wscale = wscale;
214 
215 		switch (mss_mod) {
216 		case T_DC:
217 			fp.fp_flags |= PF_OSFP_MSS_DC;
218 			break;
219 		case T_MOD:
220 			fp.fp_flags |= PF_OSFP_MSS_MOD;
221 			break;
222 		}
223 		fp.fp_mss = mss;
224 
225 		fp.fp_tcpopts = packed_tcpopts;
226 		fp.fp_optcnt = optcnt;
227 		if (ts0)
228 			fp.fp_flags |= PF_OSFP_TS0;
229 
230 		if (class[0] == '@')
231 			fp.fp_os.fp_enflags |= PF_OSFP_GENERIC;
232 		if (class[0] == '*')
233 			fp.fp_os.fp_enflags |= PF_OSFP_NODETAIL;
234 
235 		if (class[0] == '@' || class[0] == '*')
236 			strlcpy(fp.fp_os.fp_class_nm, class + 1,
237 			    sizeof(fp.fp_os.fp_class_nm));
238 		else
239 			strlcpy(fp.fp_os.fp_class_nm, class,
240 			    sizeof(fp.fp_os.fp_class_nm));
241 		strlcpy(fp.fp_os.fp_version_nm, version,
242 		    sizeof(fp.fp_os.fp_version_nm));
243 		strlcpy(fp.fp_os.fp_subtype_nm, subtype,
244 		    sizeof(fp.fp_os.fp_subtype_nm));
245 
246 		add_fingerprint(dev, opts, &fp);
247 
248 		fp.fp_flags |= (PF_OSFP_DF | PF_OSFP_INET6);
249 		fp.fp_psize += sizeof(struct ip6_hdr) - sizeof(struct ip);
250 		add_fingerprint(dev, opts, &fp);
251 	}
252 
253 	if (class)
254 		free(class);
255 	if (version)
256 		free(version);
257 	if (subtype)
258 		free(subtype);
259 	if (desc)
260 		free(desc);
261 	if (tcpopts)
262 		free(tcpopts);
263 
264 	fclose(in);
265 
266 	if (opts & PF_OPT_VERBOSE2)
267 		printf("Loaded %d passive OS fingerprints\n",
268 		    fingerprint_count);
269 	return (0);
270 }
271 
272 /* flush the kernel's fingerprints */
273 void
pfctl_clear_fingerprints(int dev,int opts)274 pfctl_clear_fingerprints(int dev, int opts)
275 {
276 	if (ioctl(dev, DIOCOSFPFLUSH))
277 		err(1, "DIOCOSFPFLUSH");
278 }
279 
280 /* flush pfctl's view of the fingerprints */
281 void
pfctl_flush_my_fingerprints(struct name_list * list)282 pfctl_flush_my_fingerprints(struct name_list *list)
283 {
284 	struct name_entry *nm;
285 
286 	while ((nm = LIST_FIRST(list)) != NULL) {
287 		LIST_REMOVE(nm, nm_entry);
288 		pfctl_flush_my_fingerprints(&nm->nm_sublist);
289 		free(nm);
290 	}
291 	fingerprint_count = 0;
292 	class_count = 0;
293 }
294 
295 /* Fetch the active fingerprints from the kernel */
296 int
pfctl_load_fingerprints(int dev,int opts)297 pfctl_load_fingerprints(int dev, int opts)
298 {
299 	struct pf_osfp_ioctl io;
300 	int i;
301 
302 	pfctl_flush_my_fingerprints(&classes);
303 
304 	for (i = 0; i >= 0; i++) {
305 		memset(&io, 0, sizeof(io));
306 		io.fp_getnum = i;
307 		if (ioctl(dev, DIOCOSFPGET, &io)) {
308 			if (errno == EBUSY)
309 				break;
310 			warn("DIOCOSFPGET");
311 			return (1);
312 		}
313 		import_fingerprint(&io);
314 	}
315 	return (0);
316 }
317 
318 /* List the fingerprints */
319 void
pfctl_show_fingerprints(int opts)320 pfctl_show_fingerprints(int opts)
321 {
322 	if (LIST_FIRST(&classes) != NULL) {
323 		if (opts & PF_OPT_SHOWALL) {
324 			pfctl_print_title("OS FINGERPRINTS:");
325 			printf("%u fingerprints loaded\n", fingerprint_count);
326 		} else {
327 			printf("Class\tVersion\tSubtype(subversion)\n");
328 			printf("-----\t-------\t-------------------\n");
329 			sort_name_list(opts, &classes);
330 			print_name_list(opts, &classes, "");
331 		}
332 	}
333 }
334 
335 /* Lookup a fingerprint */
336 pf_osfp_t
pfctl_get_fingerprint(const char * name)337 pfctl_get_fingerprint(const char *name)
338 {
339 	struct name_entry *nm, *class_nm, *version_nm, *subtype_nm;
340 	pf_osfp_t ret = PF_OSFP_NOMATCH;
341 	int class, version, subtype;
342 	int unp_class, unp_version, unp_subtype;
343 	int wr_len, version_len, subtype_len;
344 	char *ptr, *wr_name;
345 
346 	if (strcasecmp(name, "unknown") == 0)
347 		return (PF_OSFP_UNKNOWN);
348 
349 	/* Try most likely no version and no subtype */
350 	if ((nm = lookup_name_list(&classes, name))) {
351 		class = nm->nm_num;
352 		version = PF_OSFP_ANY;
353 		subtype = PF_OSFP_ANY;
354 		goto found;
355 	} else {
356 
357 		/* Chop it up into class/version/subtype */
358 
359 		if ((wr_name = strdup(name)) == NULL)
360 			err(1, "malloc");
361 		if ((ptr = strchr(wr_name, ' ')) == NULL) {
362 			free(wr_name);
363 			return (PF_OSFP_NOMATCH);
364 		}
365 		*ptr++ = '\0';
366 
367 		/* The class is easy to find since it is delimited by a space */
368 		if ((class_nm = lookup_name_list(&classes, wr_name)) == NULL) {
369 			free(wr_name);
370 			return (PF_OSFP_NOMATCH);
371 		}
372 		class = class_nm->nm_num;
373 
374 		/* Try no subtype */
375 		if ((version_nm = lookup_name_list(&class_nm->nm_sublist, ptr)))
376 		{
377 			version = version_nm->nm_num;
378 			subtype = PF_OSFP_ANY;
379 			free(wr_name);
380 			goto found;
381 		}
382 
383 
384 		/*
385 		 * There must be a version and a subtype.
386 		 * We'll do some fuzzy matching to pick up things like:
387 		 *   Linux 2.2.14 (version=2.2 subtype=14)
388 		 *   FreeBSD 4.0-STABLE (version=4.0 subtype=STABLE)
389 		 *   Windows 2000 SP2	(version=2000 subtype=SP2)
390 		 */
391 #define CONNECTOR(x)	((x) == '.' || (x) == ' ' || (x) == '\t' || (x) == '-')
392 		wr_len = strlen(ptr);
393 		LIST_FOREACH(version_nm, &class_nm->nm_sublist, nm_entry) {
394 			version_len = strlen(version_nm->nm_name);
395 			if (wr_len < version_len + 2 ||
396 			    !CONNECTOR(ptr[version_len]))
397 				continue;
398 			/* first part of the string must be version */
399 			if (strncasecmp(ptr, version_nm->nm_name,
400 			    version_len))
401 				continue;
402 
403 			LIST_FOREACH(subtype_nm, &version_nm->nm_sublist,
404 			    nm_entry) {
405 				subtype_len = strlen(subtype_nm->nm_name);
406 				if (wr_len != version_len + subtype_len + 1)
407 					continue;
408 
409 				/* last part of the string must be subtype */
410 				if (strcasecmp(&ptr[version_len+1],
411 				    subtype_nm->nm_name) != 0)
412 					continue;
413 
414 				/* Found it!! */
415 				version = version_nm->nm_num;
416 				subtype = subtype_nm->nm_num;
417 				free(wr_name);
418 				goto found;
419 			}
420 		}
421 
422 		free(wr_name);
423 		return (PF_OSFP_NOMATCH);
424 	}
425 
426 found:
427 	PF_OSFP_PACK(ret, class, version, subtype);
428 	if (ret != PF_OSFP_NOMATCH) {
429 		PF_OSFP_UNPACK(ret, unp_class, unp_version, unp_subtype);
430 		if (class != unp_class) {
431 			fprintf(stderr, "warning: fingerprint table overflowed "
432 			    "classes\n");
433 			return (PF_OSFP_NOMATCH);
434 		}
435 		if (version != unp_version) {
436 			fprintf(stderr, "warning: fingerprint table overflowed "
437 			    "versions\n");
438 			return (PF_OSFP_NOMATCH);
439 		}
440 		if (subtype != unp_subtype) {
441 			fprintf(stderr, "warning: fingerprint table overflowed "
442 			    "subtypes\n");
443 			return (PF_OSFP_NOMATCH);
444 		}
445 	}
446 	if (ret == PF_OSFP_ANY) {
447 		/* should never happen */
448 		fprintf(stderr, "warning: fingerprint packed to 'any'\n");
449 		return (PF_OSFP_NOMATCH);
450 	}
451 
452 	return (ret);
453 }
454 
455 /* Lookup a fingerprint name by ID */
456 char *
pfctl_lookup_fingerprint(pf_osfp_t fp,char * buf,size_t len)457 pfctl_lookup_fingerprint(pf_osfp_t fp, char *buf, size_t len)
458 {
459 	int class, version, subtype;
460 	struct name_list *list;
461 	struct name_entry *nm;
462 
463 	char *class_name, *version_name, *subtype_name;
464 	class_name = version_name = subtype_name = NULL;
465 
466 	if (fp == PF_OSFP_UNKNOWN) {
467 		strlcpy(buf, "unknown", len);
468 		return (buf);
469 	}
470 	if (fp == PF_OSFP_ANY) {
471 		strlcpy(buf, "any", len);
472 		return (buf);
473 	}
474 
475 	PF_OSFP_UNPACK(fp, class, version, subtype);
476 	if (class >= (1 << _FP_CLASS_BITS) ||
477 	    version >= (1 << _FP_VERSION_BITS) ||
478 	    subtype >= (1 << _FP_SUBTYPE_BITS)) {
479 		warnx("PF_OSFP_UNPACK(0x%x) failed!!", fp);
480 		strlcpy(buf, "nomatch", len);
481 		return (buf);
482 	}
483 
484 	LIST_FOREACH(nm, &classes, nm_entry) {
485 		if (nm->nm_num == class) {
486 			class_name = nm->nm_name;
487 			if (version == PF_OSFP_ANY)
488 				goto found;
489 			list = &nm->nm_sublist;
490 			LIST_FOREACH(nm, list, nm_entry) {
491 				if (nm->nm_num == version) {
492 					version_name = nm->nm_name;
493 					if (subtype == PF_OSFP_ANY)
494 						goto found;
495 					list = &nm->nm_sublist;
496 					LIST_FOREACH(nm, list, nm_entry) {
497 						if (nm->nm_num == subtype) {
498 							subtype_name =
499 							    nm->nm_name;
500 							goto found;
501 						}
502 					} /* foreach subtype */
503 					strlcpy(buf, "nomatch", len);
504 					return (buf);
505 				}
506 			} /* foreach version */
507 			strlcpy(buf, "nomatch", len);
508 			return (buf);
509 		}
510 	} /* foreach class */
511 
512 	strlcpy(buf, "nomatch", len);
513 	return (buf);
514 
515 found:
516 	snprintf(buf, len, "%s", class_name);
517 	if (version_name) {
518 		strlcat(buf, " ", len);
519 		strlcat(buf, version_name, len);
520 		if (subtype_name) {
521 			if (strchr(version_name, ' '))
522 				strlcat(buf, " ", len);
523 			else if (strchr(version_name, '.') &&
524 			    isdigit(*subtype_name))
525 				strlcat(buf, ".", len);
526 			else
527 				strlcat(buf, " ", len);
528 			strlcat(buf, subtype_name, len);
529 		}
530 	}
531 	return (buf);
532 }
533 
534 /* lookup a name in a list */
535 struct name_entry *
lookup_name_list(struct name_list * list,const char * name)536 lookup_name_list(struct name_list *list, const char *name)
537 {
538 	struct name_entry *nm;
539 	LIST_FOREACH(nm, list, nm_entry)
540 		if (strcasecmp(name, nm->nm_name) == 0)
541 			return (nm);
542 
543 	return (NULL);
544 }
545 
546 
547 void
add_fingerprint(int dev,int opts,struct pf_osfp_ioctl * fp)548 add_fingerprint(int dev, int opts, struct pf_osfp_ioctl *fp)
549 {
550 	struct pf_osfp_ioctl fptmp;
551 	struct name_entry *nm_class, *nm_version, *nm_subtype;
552 	int class, version, subtype;
553 
554 /* We expand #-# or #.#-#.# version/subtypes into multiple fingerprints */
555 #define EXPAND(field) do {						\
556 	int _dot = -1, _start = -1, _end = -1, _i = 0;			\
557 	/* pick major version out of #.# */				\
558 	if (isdigit(fp->field[_i]) && fp->field[_i+1] == '.') {		\
559 		_dot = fp->field[_i] - '0';				\
560 		_i += 2;						\
561 	}								\
562 	if (isdigit(fp->field[_i]))					\
563 		_start = fp->field[_i++] - '0';				\
564 	else								\
565 		break;							\
566 	if (isdigit(fp->field[_i]))					\
567 		_start = (_start * 10) + fp->field[_i++] - '0';		\
568 	if (fp->field[_i++] != '-')					\
569 		break;							\
570 	if (isdigit(fp->field[_i]) && fp->field[_i+1] == '.' &&		\
571 	    fp->field[_i] - '0' == _dot)				\
572 		_i += 2;						\
573 	else if (_dot != -1)						\
574 		break;							\
575 	if (isdigit(fp->field[_i]))					\
576 		_end = fp->field[_i++] - '0';				\
577 	else								\
578 		break;							\
579 	if (isdigit(fp->field[_i]))					\
580 		_end = (_end * 10) + fp->field[_i++] - '0';		\
581 	if (isdigit(fp->field[_i]))					\
582 		_end = (_end * 10) + fp->field[_i++] - '0';		\
583 	if (fp->field[_i] != '\0')					\
584 		break;							\
585 	memcpy(&fptmp, fp, sizeof(fptmp));				\
586 	for (;_start <= _end; _start++) {				\
587 		memset(fptmp.field, 0, sizeof(fptmp.field));		\
588 		fptmp.fp_os.fp_enflags |= PF_OSFP_EXPANDED;		\
589 		if (_dot == -1)						\
590 			snprintf(fptmp.field, sizeof(fptmp.field),	\
591 			    "%d", _start);				\
592 		    else						\
593 			snprintf(fptmp.field, sizeof(fptmp.field),	\
594 			    "%d.%d", _dot, _start);			\
595 		add_fingerprint(dev, opts, &fptmp);			\
596 	}								\
597 } while(0)
598 
599 	/* We allow "#-#" as a version or subtype and we'll expand it */
600 	EXPAND(fp_os.fp_version_nm);
601 	EXPAND(fp_os.fp_subtype_nm);
602 
603 	if (strcasecmp(fp->fp_os.fp_class_nm, "nomatch") == 0)
604 		errx(1, "fingerprint class \"nomatch\" is reserved");
605 
606 	version = PF_OSFP_ANY;
607 	subtype = PF_OSFP_ANY;
608 
609 	nm_class = fingerprint_name_entry(&classes, fp->fp_os.fp_class_nm);
610 	if (nm_class->nm_num == 0)
611 		nm_class->nm_num = ++class_count;
612 	class = nm_class->nm_num;
613 
614 	nm_version = fingerprint_name_entry(&nm_class->nm_sublist,
615 	    fp->fp_os.fp_version_nm);
616 	if (nm_version) {
617 		if (nm_version->nm_num == 0)
618 			nm_version->nm_num = ++nm_class->nm_sublist_num;
619 		version = nm_version->nm_num;
620 		nm_subtype = fingerprint_name_entry(&nm_version->nm_sublist,
621 		    fp->fp_os.fp_subtype_nm);
622 		if (nm_subtype) {
623 			if (nm_subtype->nm_num == 0)
624 				nm_subtype->nm_num =
625 				    ++nm_version->nm_sublist_num;
626 			subtype = nm_subtype->nm_num;
627 		}
628 	}
629 
630 
631 	DEBUG(fp, "\tsignature %d:%d:%d %s", class, version, subtype,
632 	    print_ioctl(fp));
633 
634 	PF_OSFP_PACK(fp->fp_os.fp_os, class, version, subtype);
635 	fingerprint_count++;
636 
637 #ifdef FAKE_PF_KERNEL
638 	/* Linked to the sys/net/pf_osfp.c.  Call pf_osfp_add() */
639 	if ((errno = pf_osfp_add(fp)))
640 #else
641 	if ((opts & PF_OPT_NOACTION) == 0 && ioctl(dev, DIOCOSFPADD, fp))
642 #endif /* FAKE_PF_KERNEL */
643 	{
644 		if (errno == EEXIST) {
645 			warn("Duplicate signature for %s %s %s",
646 				fp->fp_os.fp_class_nm,
647 				fp->fp_os.fp_version_nm,
648 				fp->fp_os.fp_subtype_nm);
649 
650 		} else {
651 			err(1, "DIOCOSFPADD");
652 		}
653 	}
654 }
655 
656 /* import a fingerprint from the kernel */
657 void
import_fingerprint(struct pf_osfp_ioctl * fp)658 import_fingerprint(struct pf_osfp_ioctl *fp)
659 {
660 	struct name_entry *nm_class, *nm_version, *nm_subtype;
661 	int class, version, subtype;
662 
663 	PF_OSFP_UNPACK(fp->fp_os.fp_os, class, version, subtype);
664 
665 	nm_class = fingerprint_name_entry(&classes, fp->fp_os.fp_class_nm);
666 	if (nm_class->nm_num == 0) {
667 		nm_class->nm_num = class;
668 		class_count = MAX(class_count, class);
669 	}
670 
671 	nm_version = fingerprint_name_entry(&nm_class->nm_sublist,
672 	    fp->fp_os.fp_version_nm);
673 	if (nm_version) {
674 		if (nm_version->nm_num == 0) {
675 			nm_version->nm_num = version;
676 			nm_class->nm_sublist_num = MAX(nm_class->nm_sublist_num,
677 			    version);
678 		}
679 		nm_subtype = fingerprint_name_entry(&nm_version->nm_sublist,
680 		    fp->fp_os.fp_subtype_nm);
681 		if (nm_subtype) {
682 			if (nm_subtype->nm_num == 0) {
683 				nm_subtype->nm_num = subtype;
684 				nm_version->nm_sublist_num =
685 				    MAX(nm_version->nm_sublist_num, subtype);
686 			}
687 		}
688 	}
689 
690 
691 	fingerprint_count++;
692 	DEBUG(fp, "import signature %d:%d:%d", class, version, subtype);
693 }
694 
695 /* Find an entry for a fingerprints class/version/subtype */
696 struct name_entry *
fingerprint_name_entry(struct name_list * list,char * name)697 fingerprint_name_entry(struct name_list *list, char *name)
698 {
699 	struct name_entry *nm_entry;
700 
701 	if (name == NULL || strlen(name) == 0)
702 		return (NULL);
703 
704 	LIST_FOREACH(nm_entry, list, nm_entry) {
705 		if (strcasecmp(nm_entry->nm_name, name) == 0) {
706 			/* We'll move this to the front of the list later */
707 			LIST_REMOVE(nm_entry, nm_entry);
708 			break;
709 		}
710 	}
711 	if (nm_entry == NULL) {
712 		nm_entry = calloc(1, sizeof(*nm_entry));
713 		if (nm_entry == NULL)
714 			err(1, "calloc");
715 		LIST_INIT(&nm_entry->nm_sublist);
716 		strlcpy(nm_entry->nm_name, name, sizeof(nm_entry->nm_name));
717 	}
718 	LIST_INSERT_HEAD(list, nm_entry, nm_entry);
719 	return (nm_entry);
720 }
721 
722 
723 void
print_name_list(int opts,struct name_list * nml,const char * prefix)724 print_name_list(int opts, struct name_list *nml, const char *prefix)
725 {
726 	char newprefix[32];
727 	struct name_entry *nm;
728 
729 	LIST_FOREACH(nm, nml, nm_entry) {
730 		snprintf(newprefix, sizeof(newprefix), "%s%s\t", prefix,
731 		    nm->nm_name);
732 		printf("%s\n", newprefix);
733 		print_name_list(opts, &nm->nm_sublist, newprefix);
734 	}
735 }
736 
737 void
sort_name_list(int opts,struct name_list * nml)738 sort_name_list(int opts, struct name_list *nml)
739 {
740 	struct name_list new;
741 	struct name_entry *nm, *nmsearch, *nmlast;
742 
743 	/* yes yes, it's a very slow sort.  so sue me */
744 
745 	LIST_INIT(&new);
746 
747 	while ((nm = LIST_FIRST(nml)) != NULL) {
748 		LIST_REMOVE(nm, nm_entry);
749 		nmlast = NULL;
750 		LIST_FOREACH(nmsearch, &new, nm_entry) {
751 			if (strcasecmp(nmsearch->nm_name, nm->nm_name) > 0) {
752 				LIST_INSERT_BEFORE(nmsearch, nm, nm_entry);
753 				break;
754 			}
755 			nmlast = nmsearch;
756 		}
757 		if (nmsearch == NULL) {
758 			if (nmlast)
759 				LIST_INSERT_AFTER(nmlast, nm, nm_entry);
760 			else
761 				LIST_INSERT_HEAD(&new, nm, nm_entry);
762 		}
763 
764 		sort_name_list(opts, &nm->nm_sublist);
765 	}
766 	nmlast = NULL;
767 	while ((nm = LIST_FIRST(&new)) != NULL) {
768 		LIST_REMOVE(nm, nm_entry);
769 		if (nmlast == NULL)
770 			LIST_INSERT_HEAD(nml, nm, nm_entry);
771 		else
772 			LIST_INSERT_AFTER(nmlast, nm, nm_entry);
773 		nmlast = nm;
774 	}
775 }
776 
777 /* parse the next integer in a formatted config file line */
778 int
get_int(char ** line,size_t * len,int * var,int * mod,const char * name,int flags,int max,const char * filename,int lineno)779 get_int(char **line, size_t *len, int *var, int *mod,
780     const char *name, int flags, int max, const char *filename, int lineno)
781 {
782 	int fieldlen, i;
783 	char *field;
784 	long val = 0;
785 
786 	if (mod)
787 		*mod = 0;
788 	*var = 0;
789 
790 	field = get_field(line, len, &fieldlen);
791 	if (field == NULL)
792 		return (1);
793 	if (fieldlen == 0) {
794 		fprintf(stderr, "%s:%d empty %s\n", filename, lineno, name);
795 		return (1);
796 	}
797 
798 	i = 0;
799 	if ((*field == '%' || *field == 'S' || *field == 'T' || *field == '*')
800 	    && fieldlen >= 1) {
801 		switch (*field) {
802 		case 'S':
803 			if (mod && (flags & T_MSS))
804 				*mod = T_MSS;
805 			if (fieldlen == 1)
806 				return (0);
807 			break;
808 		case 'T':
809 			if (mod && (flags & T_MTU))
810 				*mod = T_MTU;
811 			if (fieldlen == 1)
812 				return (0);
813 			break;
814 		case '*':
815 			if (fieldlen != 1) {
816 				fprintf(stderr, "%s:%d long '%c' %s\n",
817 				    filename, lineno, *field, name);
818 				return (1);
819 			}
820 			if (mod && (flags & T_DC)) {
821 				*mod = T_DC;
822 				return (0);
823 			}
824 		case '%':
825 			if (mod && (flags & T_MOD))
826 				*mod = T_MOD;
827 			if (fieldlen == 1) {
828 				fprintf(stderr, "%s:%d modulus %s must have a "
829 				    "value\n", filename, lineno, name);
830 				return (1);
831 			}
832 			break;
833 		}
834 		if (mod == NULL || *mod == 0) {
835 			fprintf(stderr, "%s:%d does not allow %c' %s\n",
836 			    filename, lineno, *field, name);
837 			return (1);
838 		}
839 		i++;
840 	}
841 
842 	for (; i < fieldlen; i++) {
843 		if (field[i] < '0' || field[i] > '9') {
844 			fprintf(stderr, "%s:%d non-digit character in %s\n",
845 			    filename, lineno, name);
846 			return (1);
847 		}
848 		val = val * 10 + field[i] - '0';
849 		if (val < 0) {
850 			fprintf(stderr, "%s:%d %s overflowed\n", filename,
851 			    lineno, name);
852 			return (1);
853 		}
854 	}
855 
856 	if (val > max) {
857 		fprintf(stderr, "%s:%d %s value %ld > %d\n", filename, lineno,
858 		    name, val, max);
859 		return (1);
860 	}
861 	*var = (int)val;
862 
863 	return (0);
864 }
865 
866 /* parse the next string in a formatted config file line */
867 int
get_str(char ** line,size_t * len,char ** v,const char * name,int minlen,const char * filename,int lineno)868 get_str(char **line, size_t *len, char **v, const char *name, int minlen,
869     const char *filename, int lineno)
870 {
871 	int fieldlen;
872 	char *ptr;
873 
874 	ptr = get_field(line, len, &fieldlen);
875 	if (ptr == NULL)
876 		return (1);
877 	if (fieldlen < minlen) {
878 		fprintf(stderr, "%s:%d too short %s\n", filename, lineno, name);
879 		return (1);
880 	}
881 	if ((*v = malloc(fieldlen + 1)) == NULL) {
882 		perror("malloc()");
883 		return (1);
884 	}
885 	memcpy(*v, ptr, fieldlen);
886 	(*v)[fieldlen] = '\0';
887 
888 	return (0);
889 }
890 
891 /* Parse out the TCP opts */
892 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)893 get_tcpopts(const char *filename, int lineno, const char *tcpopts,
894     pf_tcpopts_t *packed, int *optcnt, int *mss, int *mss_mod, int *wscale,
895     int *wscale_mod, int *ts0)
896 {
897 	int i, opt;
898 
899 	*packed = 0;
900 	*optcnt = 0;
901 	*wscale = 0;
902 	*wscale_mod = T_DC;
903 	*mss = 0;
904 	*mss_mod = T_DC;
905 	*ts0 = 0;
906 	if (strcmp(tcpopts, ".") == 0)
907 		return (0);
908 
909 	for (i = 0; tcpopts[i] && *optcnt < PF_OSFP_MAX_OPTS;) {
910 		switch ((opt = toupper(tcpopts[i++]))) {
911 		case 'N':	/* FALLTHROUGH */
912 		case 'S':
913 			*packed = (*packed << PF_OSFP_TCPOPT_BITS) |
914 			    (opt == 'N' ? PF_OSFP_TCPOPT_NOP :
915 			    PF_OSFP_TCPOPT_SACK);
916 			break;
917 		case 'W':	/* FALLTHROUGH */
918 		case 'M': {
919 			int *this_mod, *this;
920 
921 			if (opt == 'W') {
922 				this = wscale;
923 				this_mod = wscale_mod;
924 			} else {
925 				this = mss;
926 				this_mod = mss_mod;
927 			}
928 			*this = 0;
929 			*this_mod = 0;
930 
931 			*packed = (*packed << PF_OSFP_TCPOPT_BITS) |
932 			    (opt == 'W' ? PF_OSFP_TCPOPT_WSCALE :
933 			    PF_OSFP_TCPOPT_MSS);
934 			if (tcpopts[i] == '*' && (tcpopts[i + 1] == '\0' ||
935 			    tcpopts[i + 1] == ',')) {
936 				*this_mod = T_DC;
937 				i++;
938 				break;
939 			}
940 
941 			if (tcpopts[i] == '%') {
942 				*this_mod = T_MOD;
943 				i++;
944 			}
945 			do {
946 				if (!isdigit(tcpopts[i])) {
947 					fprintf(stderr, "%s:%d unknown "
948 					    "character '%c' in %c TCP opt\n",
949 					    filename, lineno, tcpopts[i], opt);
950 					return (1);
951 				}
952 				*this = (*this * 10) + tcpopts[i++] - '0';
953 			} while(tcpopts[i] != ',' && tcpopts[i] != '\0');
954 			break;
955 		}
956 		case 'T':
957 			if (tcpopts[i] == '0') {
958 				*ts0 = 1;
959 				i++;
960 			}
961 			*packed = (*packed << PF_OSFP_TCPOPT_BITS) |
962 			    PF_OSFP_TCPOPT_TS;
963 			break;
964 		}
965 		(*optcnt) ++;
966 		if (tcpopts[i] == '\0')
967 			break;
968 		if (tcpopts[i] != ',') {
969 			fprintf(stderr, "%s:%d unknown option to %c TCP opt\n",
970 			    filename, lineno, opt);
971 			return (1);
972 		}
973 		i++;
974 	}
975 
976 	return (0);
977 }
978 
979 /* rip the next field ouf of a formatted config file line */
980 char *
get_field(char ** line,size_t * len,int * fieldlen)981 get_field(char **line, size_t *len, int *fieldlen)
982 {
983 	char *ret, *ptr = *line;
984 	size_t plen = *len;
985 
986 
987 	while (plen && isspace(*ptr)) {
988 		plen--;
989 		ptr++;
990 	}
991 	ret = ptr;
992 	*fieldlen = 0;
993 
994 	for (; plen > 0 && *ptr != ':'; plen--, ptr++)
995 		(*fieldlen)++;
996 	if (plen) {
997 		*line = ptr + 1;
998 		*len = plen - 1;
999 	} else {
1000 		*len = 0;
1001 	}
1002 	while (*fieldlen && isspace(ret[*fieldlen - 1]))
1003 		(*fieldlen)--;
1004 	return (ret);
1005 }
1006 
1007 
1008 const char *
print_ioctl(struct pf_osfp_ioctl * fp)1009 print_ioctl(struct pf_osfp_ioctl *fp)
1010 {
1011 	static char buf[1024];
1012 	char tmp[32];
1013 	int i, opt;
1014 
1015 	*buf = '\0';
1016 	if (fp->fp_flags & PF_OSFP_WSIZE_DC)
1017 		strlcat(buf, "*", sizeof(buf));
1018 	else if (fp->fp_flags & PF_OSFP_WSIZE_MSS)
1019 		strlcat(buf, "S", sizeof(buf));
1020 	else if (fp->fp_flags & PF_OSFP_WSIZE_MTU)
1021 		strlcat(buf, "T", sizeof(buf));
1022 	else {
1023 		if (fp->fp_flags & PF_OSFP_WSIZE_MOD)
1024 			strlcat(buf, "%", sizeof(buf));
1025 		snprintf(tmp, sizeof(tmp), "%d", fp->fp_wsize);
1026 		strlcat(buf, tmp, sizeof(buf));
1027 	}
1028 	strlcat(buf, ":", sizeof(buf));
1029 
1030 	snprintf(tmp, sizeof(tmp), "%d", fp->fp_ttl);
1031 	strlcat(buf, tmp, sizeof(buf));
1032 	strlcat(buf, ":", sizeof(buf));
1033 
1034 	if (fp->fp_flags & PF_OSFP_DF)
1035 		strlcat(buf, "1", sizeof(buf));
1036 	else
1037 		strlcat(buf, "0", sizeof(buf));
1038 	strlcat(buf, ":", sizeof(buf));
1039 
1040 	if (fp->fp_flags & PF_OSFP_PSIZE_DC)
1041 		strlcat(buf, "*", sizeof(buf));
1042 	else {
1043 		if (fp->fp_flags & PF_OSFP_PSIZE_MOD)
1044 			strlcat(buf, "%", sizeof(buf));
1045 		snprintf(tmp, sizeof(tmp), "%d", fp->fp_psize);
1046 		strlcat(buf, tmp, sizeof(buf));
1047 	}
1048 	strlcat(buf, ":", sizeof(buf));
1049 
1050 	if (fp->fp_optcnt == 0)
1051 		strlcat(buf, ".", sizeof(buf));
1052 	for (i = fp->fp_optcnt - 1; i >= 0; i--) {
1053 		opt = fp->fp_tcpopts >> (i * PF_OSFP_TCPOPT_BITS);
1054 		opt &= (1 << PF_OSFP_TCPOPT_BITS) - 1;
1055 		switch (opt) {
1056 		case PF_OSFP_TCPOPT_NOP:
1057 			strlcat(buf, "N", sizeof(buf));
1058 			break;
1059 		case PF_OSFP_TCPOPT_SACK:
1060 			strlcat(buf, "S", sizeof(buf));
1061 			break;
1062 		case PF_OSFP_TCPOPT_TS:
1063 			strlcat(buf, "T", sizeof(buf));
1064 			if (fp->fp_flags & PF_OSFP_TS0)
1065 				strlcat(buf, "0", sizeof(buf));
1066 			break;
1067 		case PF_OSFP_TCPOPT_MSS:
1068 			strlcat(buf, "M", sizeof(buf));
1069 			if (fp->fp_flags & PF_OSFP_MSS_DC)
1070 				strlcat(buf, "*", sizeof(buf));
1071 			else {
1072 				if (fp->fp_flags & PF_OSFP_MSS_MOD)
1073 					strlcat(buf, "%", sizeof(buf));
1074 				snprintf(tmp, sizeof(tmp), "%d", fp->fp_mss);
1075 				strlcat(buf, tmp, sizeof(buf));
1076 			}
1077 			break;
1078 		case PF_OSFP_TCPOPT_WSCALE:
1079 			strlcat(buf, "W", sizeof(buf));
1080 			if (fp->fp_flags & PF_OSFP_WSCALE_DC)
1081 				strlcat(buf, "*", sizeof(buf));
1082 			else {
1083 				if (fp->fp_flags & PF_OSFP_WSCALE_MOD)
1084 					strlcat(buf, "%", sizeof(buf));
1085 				snprintf(tmp, sizeof(tmp), "%d", fp->fp_wscale);
1086 				strlcat(buf, tmp, sizeof(buf));
1087 			}
1088 			break;
1089 		}
1090 
1091 		if (i != 0)
1092 			strlcat(buf, ",", sizeof(buf));
1093 	}
1094 	strlcat(buf, ":", sizeof(buf));
1095 
1096 	strlcat(buf, fp->fp_os.fp_class_nm, sizeof(buf));
1097 	strlcat(buf, ":", sizeof(buf));
1098 	strlcat(buf, fp->fp_os.fp_version_nm, sizeof(buf));
1099 	strlcat(buf, ":", sizeof(buf));
1100 	strlcat(buf, fp->fp_os.fp_subtype_nm, sizeof(buf));
1101 	strlcat(buf, ":", sizeof(buf));
1102 
1103 	snprintf(tmp, sizeof(tmp), "TcpOpts %d 0x%llx", fp->fp_optcnt,
1104 	    (long long int)fp->fp_tcpopts);
1105 	strlcat(buf, tmp, sizeof(buf));
1106 
1107 	return (buf);
1108 }
1109