xref: /netbsd/sys/net/npf/npf_ctl.c (revision 6550d01e)
1 /*	$NetBSD: npf_ctl.c,v 1.6 2011/02/02 02:20:25 rmind Exp $	*/
2 
3 /*-
4  * Copyright (c) 2009-2011 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This material is based upon work partially supported by The
8  * NetBSD Foundation under a contract with Mindaugas Rasiukevicius.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * NPF device control.
34  *
35  * Implementation of (re)loading, construction of tables and rules.
36  * NPF proplib(9) dictionary consumer.
37  */
38 
39 #include <sys/cdefs.h>
40 __KERNEL_RCSID(0, "$NetBSD: npf_ctl.c,v 1.6 2011/02/02 02:20:25 rmind Exp $");
41 
42 #include <sys/param.h>
43 #include <sys/conf.h>
44 #include <sys/kernel.h>
45 
46 #include <prop/proplib.h>
47 
48 #include "npf_ncode.h"
49 #include "npf_impl.h"
50 
51 /*
52  * npfctl_switch: enable or disable packet inspection.
53  */
54 int
55 npfctl_switch(void *data)
56 {
57 	const bool onoff = *(int *)data ? true : false;
58 	int error;
59 
60 	if (onoff) {
61 		/* Enable: add pfil hooks. */
62 		error = npf_register_pfil();
63 	} else {
64 		/* Disable: remove pfil hooks. */
65 		npf_unregister_pfil();
66 		error = 0;
67 	}
68 	return error;
69 }
70 
71 static int __noinline
72 npf_mk_tables(npf_tableset_t *tblset, prop_array_t tables)
73 {
74 	prop_object_iterator_t it;
75 	prop_dictionary_t tbldict;
76 	int error = 0;
77 
78 	/* Tables - array. */
79 	if (prop_object_type(tables) != PROP_TYPE_ARRAY)
80 		return EINVAL;
81 
82 	it = prop_array_iterator(tables);
83 	while ((tbldict = prop_object_iterator_next(it)) != NULL) {
84 		prop_dictionary_t ent;
85 		prop_object_iterator_t eit;
86 		prop_array_t entries;
87 		npf_table_t *t;
88 		u_int tid;
89 		int type;
90 
91 		/* Table - dictionary. */
92 		if (prop_object_type(tbldict) != PROP_TYPE_DICTIONARY) {
93 			error = EINVAL;
94 			break;
95 		}
96 
97 		/* Table ID and type. */
98 		prop_dictionary_get_uint32(tbldict, "id", &tid);
99 		prop_dictionary_get_int32(tbldict, "type", &type);
100 
101 		/* Validate them. */
102 		error = npf_table_check(tblset, tid, type);
103 		if (error)
104 			break;
105 
106 		/* Create and insert the table. */
107 		t = npf_table_create(tid, type, 1024);	/* XXX */
108 		if (t == NULL) {
109 			error = ENOMEM;
110 			break;
111 		}
112 		error = npf_tableset_insert(tblset, t);
113 		KASSERT(error == 0);
114 
115 		/* Entries. */
116 		entries = prop_dictionary_get(tbldict, "entries");
117 		if (prop_object_type(entries) != PROP_TYPE_ARRAY) {
118 			error = EINVAL;
119 			break;
120 		}
121 		eit = prop_array_iterator(entries);
122 		while ((ent = prop_object_iterator_next(eit)) != NULL) {
123 			in_addr_t addr, mask;	/* XXX: IPv6 */
124 
125 			/* Get address and mask.  Add a table entry. */
126 			prop_dictionary_get_uint32(ent, "addr", &addr);
127 			prop_dictionary_get_uint32(ent, "mask", &mask);
128 			error = npf_table_add_v4cidr(tblset, tid, addr, mask);
129 			if (error)
130 				break;
131 		}
132 		prop_object_iterator_release(eit);
133 		if (error)
134 			break;
135 	}
136 	prop_object_iterator_release(it);
137 	/*
138 	 * Note: in a case of error, caller will free the tableset.
139 	 */
140 	return error;
141 }
142 
143 static npf_rproc_t *
144 npf_mk_rproc(prop_array_t rprocs, const char *rpname)
145 {
146 	prop_object_iterator_t it;
147 	prop_dictionary_t rpdict;
148 	npf_rproc_t *rp;
149 
150 	it = prop_array_iterator(rprocs);
151 	while ((rpdict = prop_object_iterator_next(it)) != NULL) {
152 		const char *iname;
153 		prop_dictionary_get_cstring_nocopy(rpdict, "name", &iname);
154 		if (strcmp(rpname, iname) == 0)
155 			break;
156 	}
157 	prop_object_iterator_release(it);
158 	if (rpdict == NULL) {
159 		return NULL;
160 	}
161 	CTASSERT(sizeof(uintptr_t) <= sizeof(uint64_t));
162 	if (!prop_dictionary_get_uint64(rpdict, "rproc-ptr", (uint64_t *)&rp)) {
163 		rp = npf_rproc_create(rpdict);
164 		prop_dictionary_set_uint64(rpdict, "rproc-ptr",
165 		    (uint64_t)(uintptr_t)rp);
166 	}
167 	return rp;
168 }
169 
170 static int __noinline
171 npf_mk_singlerule(prop_dictionary_t rldict, prop_array_t rps, npf_rule_t **rl)
172 {
173 	const char *rnm;
174 	npf_rproc_t *rp;
175 	prop_object_t obj;
176 	size_t nc_size;
177 	void *nc;
178 
179 	/* Rule - dictionary. */
180 	if (prop_object_type(rldict) != PROP_TYPE_DICTIONARY)
181 		return EINVAL;
182 
183 	/* N-code (binary data). */
184 	obj = prop_dictionary_get(rldict, "ncode");
185 	if (obj) {
186 		const void *ncptr;
187 		int npf_err, errat;
188 
189 		/*
190 		 * Allocate, copy and validate n-code. XXX: Inefficient.
191 		 */
192 		ncptr = prop_data_data_nocopy(obj);
193 		nc_size = prop_data_size(obj);
194 		if (ncptr == NULL || nc_size > NPF_NCODE_LIMIT) {
195 			return EINVAL;
196 		}
197 		nc = npf_ncode_alloc(nc_size);
198 		if (nc == NULL) {
199 			return EINVAL;
200 		}
201 		memcpy(nc, ncptr, nc_size);
202 		npf_err = npf_ncode_validate(nc, nc_size, &errat);
203 		if (npf_err) {
204 			npf_ncode_free(nc, nc_size);
205 			/* TODO: return error details via proplib */
206 			return EINVAL;
207 		}
208 	} else {
209 		/* No n-code. */
210 		nc = NULL;
211 		nc_size = 0;
212 	}
213 
214 	/* Check for rule procedure. */
215 	if (rps && prop_dictionary_get_cstring_nocopy(rldict, "rproc", &rnm)) {
216 		rp = npf_mk_rproc(rps, rnm);
217 		if (rp == NULL) {
218 			if (nc) {
219 				npf_ncode_free(nc, nc_size);	/* XXX */
220 			}
221 			return EINVAL;
222 		}
223 	} else {
224 		rp = NULL;
225 	}
226 
227 	/* Finally, allocate and return the rule. */
228 	*rl = npf_rule_alloc(rldict, rp, nc, nc_size);
229 	return 0;
230 }
231 
232 static int __noinline
233 npf_mk_subrules(npf_ruleset_t *rlset, prop_array_t rules, prop_array_t rprocs)
234 {
235 	prop_object_iterator_t it;
236 	prop_dictionary_t rldict;
237 	int error = 0;
238 
239 	if (prop_object_type(rules) != PROP_TYPE_ARRAY) {
240 		return EINVAL;
241 	}
242 	it = prop_array_iterator(rules);
243 	while ((rldict = prop_object_iterator_next(it)) != NULL) {
244 		npf_rule_t *rl;
245 		error = npf_mk_singlerule(rldict, rprocs, &rl);
246 		if (error) {
247 			break;
248 		}
249 		npf_ruleset_insert(rlset, rl);
250 	}
251 	prop_object_iterator_release(it);
252 	return error;
253 }
254 
255 static int __noinline
256 npf_mk_rules(npf_ruleset_t *rlset, prop_array_t rules, prop_array_t rprocs)
257 {
258 	prop_object_iterator_t it;
259 	prop_dictionary_t rldict, rpdict;
260 	int error;
261 
262 	/* Rule procedures and the ruleset - arrays. */
263 	if (prop_object_type(rprocs) != PROP_TYPE_ARRAY ||
264 	    prop_object_type(rules) != PROP_TYPE_ARRAY)
265 		return EINVAL;
266 
267 	it = prop_array_iterator(rprocs);
268 	while ((rpdict = prop_object_iterator_next(it)) != NULL) {
269 		if (prop_dictionary_get(rpdict, "rproc-ptr")) {
270 			prop_object_iterator_release(it);
271 			return EINVAL;
272 		}
273 	}
274 	prop_object_iterator_release(it);
275 
276 	error = 0;
277 	it = prop_array_iterator(rules);
278 	while ((rldict = prop_object_iterator_next(it)) != NULL) {
279 		prop_array_t subrules;
280 		npf_ruleset_t *rlsetsub;
281 		npf_rule_t *rl;
282 
283 		/* Generate a single rule. */
284 		error = npf_mk_singlerule(rldict, rprocs, &rl);
285 		if (error) {
286 			break;
287 		}
288 		npf_ruleset_insert(rlset, rl);
289 
290 		/* Check for sub-rules and generate, if any. */
291 		subrules = prop_dictionary_get(rldict, "subrules");
292 		if (subrules == NULL) {
293 			/* No subrules, next.. */
294 			continue;
295 		}
296 		rlsetsub = npf_rule_subset(rl);
297 		error = npf_mk_subrules(rlsetsub, subrules, rprocs);
298 		if (error)
299 			break;
300 	}
301 	prop_object_iterator_release(it);
302 	/*
303 	 * Note: in a case of error, caller will free the ruleset.
304 	 */
305 	return error;
306 }
307 
308 static int __noinline
309 npf_mk_natlist(npf_ruleset_t *nset, prop_array_t natlist)
310 {
311 	prop_object_iterator_t it;
312 	prop_dictionary_t natdict;
313 	int error;
314 
315 	/* NAT policies - array. */
316 	if (prop_object_type(natlist) != PROP_TYPE_ARRAY)
317 		return EINVAL;
318 
319 	error = 0;
320 	it = prop_array_iterator(natlist);
321 	while ((natdict = prop_object_iterator_next(it)) != NULL) {
322 		npf_natpolicy_t *np;
323 		npf_rule_t *rl;
324 
325 		/* NAT policy - dictionary. */
326 		if (prop_object_type(natdict) != PROP_TYPE_DICTIONARY) {
327 			error = EINVAL;
328 			break;
329 		}
330 
331 		/*
332 		 * NAT policies are standard rules, plus additional
333 		 * information for translation.  Make a rule.
334 		 */
335 		error = npf_mk_singlerule(natdict, NULL, &rl);
336 		if (error) {
337 			break;
338 		}
339 		npf_ruleset_insert(nset, rl);
340 
341 		/* If rule is named, it is a group with NAT policies. */
342 		if (prop_dictionary_get(natdict, "name") &&
343 		    prop_dictionary_get(natdict, "subrules")) {
344 			continue;
345 		}
346 
347 		/* Allocate a new NAT policy and assign to the rule. */
348 		np = npf_nat_newpolicy(natdict, nset);
349 		if (np == NULL) {
350 			npf_rule_free(rl);
351 			error = ENOMEM;
352 			break;
353 		}
354 		npf_rule_setnat(rl, np);
355 	}
356 	prop_object_iterator_release(it);
357 	/*
358 	 * Note: in a case of error, caller will free entire NAT ruleset
359 	 * with assigned NAT policies.
360 	 */
361 	return error;
362 }
363 
364 /*
365  * npfctl_reload: store passed data i.e. update settings, create passed
366  * tables, rules and atomically activate all them.
367  */
368 int
369 npfctl_reload(u_long cmd, void *data)
370 {
371 	const struct plistref *pref = data;
372 	prop_array_t natlist, tables, rprocs, rules;
373 	npf_tableset_t *tblset = NULL;
374 	npf_ruleset_t *rlset = NULL;
375 	npf_ruleset_t *nset = NULL;
376 	prop_dictionary_t dict;
377 	int error;
378 
379 	/* Retrieve the dictionary. */
380 #ifdef _KERNEL
381 	error = prop_dictionary_copyin_ioctl(pref, cmd, &dict);
382 	if (error)
383 		return error;
384 #else
385 	dict = prop_dictionary_internalize_from_file(data);
386 	if (dict == NULL)
387 		return EINVAL;
388 #endif
389 	/* NAT policies. */
390 	nset = npf_ruleset_create();
391 	natlist = prop_dictionary_get(dict, "translation");
392 	error = npf_mk_natlist(nset, natlist);
393 	if (error)
394 		goto fail;
395 
396 	/* Tables. */
397 	tblset = npf_tableset_create();
398 	tables = prop_dictionary_get(dict, "tables");
399 	error = npf_mk_tables(tblset, tables);
400 	if (error)
401 		goto fail;
402 
403 	/* Rules and rule procedures. */
404 	rlset = npf_ruleset_create();
405 	rprocs = prop_dictionary_get(dict, "rprocs");
406 	rules = prop_dictionary_get(dict, "rules");
407 	error = npf_mk_rules(rlset, rules, rprocs);
408 	if (error)
409 		goto fail;
410 
411 	/*
412 	 * Finally - reload ruleset, tableset and NAT policies.
413 	 * Operation will be performed as a single transaction.
414 	 */
415 	npf_reload(rlset, tblset, nset);
416 
417 	/* Done.  Since data is consumed now, we shall not destroy it. */
418 	tblset = NULL;
419 	rlset = NULL;
420 	nset = NULL;
421 fail:
422 	/*
423 	 * Note: destroy rulesets first, to drop references to the tableset.
424 	 */
425 	KASSERT(error == 0 || (nset || rlset || tblset));
426 	if (nset) {
427 		npf_ruleset_destroy(nset);
428 	}
429 	if (rlset) {
430 		npf_ruleset_destroy(rlset);
431 	}
432 	if (tblset) {
433 		npf_tableset_destroy(tblset);
434 	}
435 	prop_object_release(dict);
436 	return error;
437 }
438 
439 /*
440  * npfctl_update_rule: reload a specific rule identified by the name.
441  */
442 int
443 npfctl_update_rule(u_long cmd, void *data)
444 {
445 	const struct plistref *pref = data;
446 	prop_dictionary_t dict;
447 	prop_array_t subrules;
448 	prop_object_t obj;
449 	npf_ruleset_t *rlset;
450 	const char *name;
451 	int error;
452 
453 #ifdef _KERNEL
454 	/* Retrieve and construct the rule. */
455 	error = prop_dictionary_copyin_ioctl(pref, cmd, &dict);
456 	if (error) {
457 		return error;
458 	}
459 #else
460 	dict = prop_dictionary_internalize_from_file(data);
461 	if (dict == NULL)
462 		return EINVAL;
463 #endif
464 	/* Create the ruleset and construct sub-rules. */
465 	rlset = npf_ruleset_create();
466 	subrules = prop_dictionary_get(dict, "subrules");
467 	error = npf_mk_subrules(rlset, subrules, NULL);
468 	if (error) {
469 		goto out;
470 	}
471 
472 	/* Lookup the rule by name, and replace its subset (sub-rules). */
473 	obj = prop_dictionary_get(dict, "name");
474 	name = prop_string_cstring_nocopy(obj);
475 	if (npf_ruleset_replace(name, rlset) == NULL) {
476 		/* Not found. */
477 		error = ENOENT;
478 out:		/* Error path. */
479 		npf_ruleset_destroy(rlset);
480 	}
481 	prop_object_release(dict);
482 	return error;
483 }
484 
485 /*
486  * npfctl_sessions_save: construct a list of sessions and export for saving.
487  */
488 int
489 npfctl_sessions_save(u_long cmd, void *data)
490 {
491 	struct plistref *pref = data;
492 	prop_dictionary_t sesdict;
493 	prop_array_t selist, nplist;
494 	int error;
495 
496 	/* Create a dictionary and two lists. */
497 	sesdict = prop_dictionary_create();
498 	selist = prop_array_create();
499 	nplist = prop_array_create();
500 
501 	/* Save the sessions. */
502 	error = npf_session_save(selist, nplist);
503 	if (error) {
504 		goto fail;
505 	}
506 
507 	/* Set the session list, NAT policy list and export the dictionary. */
508 	prop_dictionary_set(sesdict, "session-list", selist);
509 	prop_dictionary_set(sesdict, "nat-policy-list", nplist);
510 #ifdef _KERNEL
511 	error = prop_dictionary_copyout_ioctl(pref, cmd, sesdict);
512 #else
513 	error = prop_dictionary_externalize_to_file(sesdict, data) ? 0 : errno;
514 #endif
515 fail:
516 	prop_object_release(sesdict);
517 	return error;
518 }
519 
520 /*
521  * npfctl_sessions_load: import a list of sessions, reconstruct them and load.
522  */
523 int
524 npfctl_sessions_load(u_long cmd, void *data)
525 {
526 	const struct plistref *pref = data;
527 	npf_sehash_t *sehasht = NULL;
528 	prop_dictionary_t sesdict, sedict;
529 	prop_object_iterator_t it;
530 	prop_array_t selist;
531 	int error;
532 
533 	/* Retrieve the dictionary containing session and NAT policy lists. */
534 #ifdef _KERNEL
535 	error = prop_dictionary_copyin_ioctl(pref, cmd, &sesdict);
536 	if (error)
537 		return error;
538 #else
539 	sesdict = prop_dictionary_internalize_from_file(data);
540 	if (sesdict == NULL)
541 		return EINVAL;
542 #endif
543 	/*
544 	 * Note: session objects contain the references to the NAT policy
545 	 * entries.  Therefore, no need to directly access it.
546 	 */
547 	selist = prop_dictionary_get(sesdict, "session-list");
548 	if (prop_object_type(selist) != PROP_TYPE_ARRAY) {
549 		error = EINVAL;
550 		goto fail;
551 	}
552 
553 	/* Create a session hash table. */
554 	sehasht = sess_htable_create();
555 	if (sehasht == NULL) {
556 		error = ENOMEM;
557 		goto fail;
558 	}
559 
560 	/*
561 	 * Iterate through and construct each session.
562 	 */
563 	error = 0;
564 	it = prop_array_iterator(selist);
565 	npf_core_enter();
566 	while ((sedict = prop_object_iterator_next(it)) != NULL) {
567 		/* Session - dictionary. */
568 		if (prop_object_type(sedict) != PROP_TYPE_DICTIONARY) {
569 			error = EINVAL;
570 			goto fail;
571 		}
572 		/* Construct and insert real session structure. */
573 		error = npf_session_restore(sehasht, sedict);
574 		if (error) {
575 			goto fail;
576 		}
577 	}
578 	npf_core_exit();
579 	sess_htable_reload(sehasht);
580 fail:
581 	prop_object_release(selist);
582 	if (error && sehasht) {
583 		/* Destroy session table. */
584 		sess_htable_destroy(sehasht);
585 	}
586 	return error;
587 }
588 
589 /*
590  * npfctl_table: add, remove or query entries in the specified table.
591  *
592  * For maximum performance, interface is avoiding proplib(3)'s overhead.
593  */
594 int
595 npfctl_table(void *data)
596 {
597 	npf_ioctl_table_t *nct = data;
598 	int error;
599 
600 	npf_core_enter(); /* XXXSMP */
601 	switch (nct->nct_action) {
602 	case NPF_IOCTL_TBLENT_ADD:
603 		error = npf_table_add_v4cidr(NULL, nct->nct_tid,
604 		    nct->nct_addr, nct->nct_mask);
605 		break;
606 	case NPF_IOCTL_TBLENT_REM:
607 		error = npf_table_rem_v4cidr(NULL, nct->nct_tid,
608 		    nct->nct_addr, nct->nct_mask);
609 		break;
610 	default:
611 		/* XXX */
612 		error = npf_table_match_v4addr(nct->nct_tid, nct->nct_addr);
613 		if (error) {
614 			error = EINVAL;
615 		}
616 	}
617 	npf_core_exit(); /* XXXSMP */
618 	return error;
619 }
620