xref: /netbsd-src/sys/net/npf/npf_ctl.c (revision e39ef1d61eee3ccba837ee281f1e098c864487aa)
1 /*	$NetBSD: npf_ctl.c,v 1.11 2012/01/15 00:49:48 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 1.11 2012/01/15 00:49:48 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 			const npf_addr_t *addr;
124 			npf_netmask_t mask;
125 
126 			/* Get address and mask.  Add a table entry. */
127 			addr = (const npf_addr_t *)prop_data_data_nocopy(
128 			    prop_dictionary_get(ent, "addr"));
129 			prop_dictionary_get_uint8(ent, "mask", &mask);
130 			error = npf_table_add_cidr(tblset, tid, addr, mask);
131 			if (error)
132 				break;
133 		}
134 		prop_object_iterator_release(eit);
135 		if (error)
136 			break;
137 	}
138 	prop_object_iterator_release(it);
139 	/*
140 	 * Note: in a case of error, caller will free the tableset.
141 	 */
142 	return error;
143 }
144 
145 static npf_rproc_t *
146 npf_mk_rproc(prop_array_t rprocs, const char *rpname)
147 {
148 	prop_object_iterator_t it;
149 	prop_dictionary_t rpdict;
150 	npf_rproc_t *rp;
151 
152 	it = prop_array_iterator(rprocs);
153 	while ((rpdict = prop_object_iterator_next(it)) != NULL) {
154 		const char *iname;
155 		prop_dictionary_get_cstring_nocopy(rpdict, "name", &iname);
156 		if (strcmp(rpname, iname) == 0)
157 			break;
158 	}
159 	prop_object_iterator_release(it);
160 	if (rpdict == NULL) {
161 		return NULL;
162 	}
163 	CTASSERT(sizeof(uintptr_t) <= sizeof(uint64_t));
164 	if (!prop_dictionary_get_uint64(rpdict, "rproc-ptr", (uint64_t *)&rp)) {
165 		rp = npf_rproc_create(rpdict);
166 		prop_dictionary_set_uint64(rpdict, "rproc-ptr",
167 		    (uint64_t)(uintptr_t)rp);
168 	}
169 	return rp;
170 }
171 
172 static int __noinline
173 npf_mk_singlerule(prop_dictionary_t rldict, prop_array_t rps, npf_rule_t **rl)
174 {
175 	const char *rnm;
176 	npf_rproc_t *rp;
177 	prop_object_t obj;
178 	size_t nc_size;
179 	void *nc;
180 
181 	/* Rule - dictionary. */
182 	if (prop_object_type(rldict) != PROP_TYPE_DICTIONARY)
183 		return EINVAL;
184 
185 	/* N-code (binary data). */
186 	obj = prop_dictionary_get(rldict, "ncode");
187 	if (obj) {
188 		const void *ncptr;
189 		int npf_err, errat;
190 
191 		/*
192 		 * Allocate, copy and validate n-code. XXX: Inefficient.
193 		 */
194 		ncptr = prop_data_data_nocopy(obj);
195 		nc_size = prop_data_size(obj);
196 		if (ncptr == NULL || nc_size > NPF_NCODE_LIMIT) {
197 			return EINVAL;
198 		}
199 		nc = npf_ncode_alloc(nc_size);
200 		if (nc == NULL) {
201 			return EINVAL;
202 		}
203 		memcpy(nc, ncptr, nc_size);
204 		npf_err = npf_ncode_validate(nc, nc_size, &errat);
205 		if (npf_err) {
206 			npf_ncode_free(nc, nc_size);
207 			/* TODO: return error details via proplib */
208 			return EINVAL;
209 		}
210 	} else {
211 		/* No n-code. */
212 		nc = NULL;
213 		nc_size = 0;
214 	}
215 
216 	/* Check for rule procedure. */
217 	if (rps && prop_dictionary_get_cstring_nocopy(rldict, "rproc", &rnm)) {
218 		rp = npf_mk_rproc(rps, rnm);
219 		if (rp == NULL) {
220 			if (nc) {
221 				npf_ncode_free(nc, nc_size);	/* XXX */
222 			}
223 			return EINVAL;
224 		}
225 	} else {
226 		rp = NULL;
227 	}
228 
229 	/* Finally, allocate and return the rule. */
230 	*rl = npf_rule_alloc(rldict, rp, nc, nc_size);
231 	return 0;
232 }
233 
234 static int __noinline
235 npf_mk_subrules(npf_ruleset_t *rlset, prop_array_t rules, prop_array_t rprocs)
236 {
237 	prop_object_iterator_t it;
238 	prop_dictionary_t rldict;
239 	int error = 0;
240 
241 	if (prop_object_type(rules) != PROP_TYPE_ARRAY) {
242 		return EINVAL;
243 	}
244 	it = prop_array_iterator(rules);
245 	while ((rldict = prop_object_iterator_next(it)) != NULL) {
246 		npf_rule_t *rl;
247 		error = npf_mk_singlerule(rldict, rprocs, &rl);
248 		if (error) {
249 			break;
250 		}
251 		npf_ruleset_insert(rlset, rl);
252 	}
253 	prop_object_iterator_release(it);
254 	return error;
255 }
256 
257 static int __noinline
258 npf_mk_rules(npf_ruleset_t *rlset, prop_array_t rules, prop_array_t rprocs)
259 {
260 	prop_object_iterator_t it;
261 	prop_dictionary_t rldict, rpdict;
262 	int error;
263 
264 	/* Rule procedures and the ruleset - arrays. */
265 	if (prop_object_type(rprocs) != PROP_TYPE_ARRAY ||
266 	    prop_object_type(rules) != PROP_TYPE_ARRAY)
267 		return EINVAL;
268 
269 	it = prop_array_iterator(rprocs);
270 	while ((rpdict = prop_object_iterator_next(it)) != NULL) {
271 		if (prop_dictionary_get(rpdict, "rproc-ptr")) {
272 			prop_object_iterator_release(it);
273 			return EINVAL;
274 		}
275 	}
276 	prop_object_iterator_release(it);
277 
278 	error = 0;
279 	it = prop_array_iterator(rules);
280 	while ((rldict = prop_object_iterator_next(it)) != NULL) {
281 		prop_array_t subrules;
282 		npf_ruleset_t *rlsetsub;
283 		npf_rule_t *rl;
284 
285 		/* Generate a single rule. */
286 		error = npf_mk_singlerule(rldict, rprocs, &rl);
287 		if (error) {
288 			break;
289 		}
290 		npf_ruleset_insert(rlset, rl);
291 
292 		/* Check for sub-rules and generate, if any. */
293 		subrules = prop_dictionary_get(rldict, "subrules");
294 		if (subrules == NULL) {
295 			/* No subrules, next.. */
296 			continue;
297 		}
298 		rlsetsub = npf_rule_subset(rl);
299 		error = npf_mk_subrules(rlsetsub, subrules, rprocs);
300 		if (error)
301 			break;
302 	}
303 	prop_object_iterator_release(it);
304 	/*
305 	 * Note: in a case of error, caller will free the ruleset.
306 	 */
307 	return error;
308 }
309 
310 static int __noinline
311 npf_mk_natlist(npf_ruleset_t *nset, prop_array_t natlist)
312 {
313 	prop_object_iterator_t it;
314 	prop_dictionary_t natdict;
315 	int error;
316 
317 	/* NAT policies - array. */
318 	if (prop_object_type(natlist) != PROP_TYPE_ARRAY)
319 		return EINVAL;
320 
321 	error = 0;
322 	it = prop_array_iterator(natlist);
323 	while ((natdict = prop_object_iterator_next(it)) != NULL) {
324 		npf_natpolicy_t *np;
325 		npf_rule_t *rl;
326 
327 		/* NAT policy - dictionary. */
328 		if (prop_object_type(natdict) != PROP_TYPE_DICTIONARY) {
329 			error = EINVAL;
330 			break;
331 		}
332 
333 		/*
334 		 * NAT policies are standard rules, plus additional
335 		 * information for translation.  Make a rule.
336 		 */
337 		error = npf_mk_singlerule(natdict, NULL, &rl);
338 		if (error) {
339 			break;
340 		}
341 		npf_ruleset_insert(nset, rl);
342 
343 		/* If rule is named, it is a group with NAT policies. */
344 		if (prop_dictionary_get(natdict, "name") &&
345 		    prop_dictionary_get(natdict, "subrules")) {
346 			continue;
347 		}
348 
349 		/* Allocate a new NAT policy and assign to the rule. */
350 		np = npf_nat_newpolicy(natdict, nset);
351 		if (np == NULL) {
352 			npf_rule_free(rl);
353 			error = ENOMEM;
354 			break;
355 		}
356 		npf_rule_setnat(rl, np);
357 	}
358 	prop_object_iterator_release(it);
359 	/*
360 	 * Note: in a case of error, caller will free entire NAT ruleset
361 	 * with assigned NAT policies.
362 	 */
363 	return error;
364 }
365 
366 /*
367  * npfctl_reload: store passed data i.e. update settings, create passed
368  * tables, rules and atomically activate all them.
369  */
370 int
371 npfctl_reload(u_long cmd, void *data)
372 {
373 	const struct plistref *pref = data;
374 	prop_array_t natlist, tables, rprocs, rules;
375 	npf_tableset_t *tblset = NULL;
376 	npf_ruleset_t *rlset = NULL;
377 	npf_ruleset_t *nset = NULL;
378 	prop_dictionary_t dict;
379 	bool flush;
380 	int error;
381 
382 	/* Retrieve the dictionary. */
383 #ifdef _KERNEL
384 	error = prop_dictionary_copyin_ioctl(pref, cmd, &dict);
385 	if (error)
386 		return error;
387 #else
388 	dict = prop_dictionary_internalize_from_file(data);
389 	if (dict == NULL)
390 		return EINVAL;
391 #endif
392 	/* NAT policies. */
393 	nset = npf_ruleset_create();
394 	natlist = prop_dictionary_get(dict, "translation");
395 	error = npf_mk_natlist(nset, natlist);
396 	if (error) {
397 		goto fail;
398 	}
399 
400 	/* Tables. */
401 	tblset = npf_tableset_create();
402 	tables = prop_dictionary_get(dict, "tables");
403 	error = npf_mk_tables(tblset, tables);
404 	if (error) {
405 		goto fail;
406 	}
407 
408 	/* Rules and rule procedures. */
409 	rlset = npf_ruleset_create();
410 	rprocs = prop_dictionary_get(dict, "rprocs");
411 	rules = prop_dictionary_get(dict, "rules");
412 	error = npf_mk_rules(rlset, rules, rprocs);
413 	if (error) {
414 		goto fail;
415 	}
416 
417 	flush = false;
418 	prop_dictionary_get_bool(dict, "flush", &flush);
419 
420 	/*
421 	 * Finally - reload ruleset, tableset and NAT policies.
422 	 * Operation will be performed as a single transaction.
423 	 */
424 	npf_reload(rlset, tblset, nset);
425 
426 	/* Turn on/off session tracking accordingly. */
427 	npf_session_tracking(!flush);
428 
429 	/* Done.  Since data is consumed now, we shall not destroy it. */
430 	tblset = NULL;
431 	rlset = NULL;
432 	nset = NULL;
433 fail:
434 	/*
435 	 * Note: destroy rulesets first, to drop references to the tableset.
436 	 */
437 	KASSERT(error == 0 || (nset || rlset || tblset));
438 	if (nset) {
439 		npf_ruleset_destroy(nset);
440 	}
441 	if (rlset) {
442 		npf_ruleset_destroy(rlset);
443 	}
444 	if (tblset) {
445 		npf_tableset_destroy(tblset);
446 	}
447 	prop_object_release(dict);
448 	return error;
449 }
450 
451 /*
452  * npfctl_update_rule: reload a specific rule identified by the name.
453  */
454 int
455 npfctl_update_rule(u_long cmd, void *data)
456 {
457 	const struct plistref *pref = data;
458 	prop_dictionary_t dict;
459 	prop_array_t subrules;
460 	prop_object_t obj;
461 	npf_ruleset_t *rlset;
462 	const char *name;
463 	int error;
464 
465 #ifdef _KERNEL
466 	/* Retrieve and construct the rule. */
467 	error = prop_dictionary_copyin_ioctl(pref, cmd, &dict);
468 	if (error) {
469 		return error;
470 	}
471 #else
472 	dict = prop_dictionary_internalize_from_file(data);
473 	if (dict == NULL)
474 		return EINVAL;
475 #endif
476 	/* Create the ruleset and construct sub-rules. */
477 	rlset = npf_ruleset_create();
478 	subrules = prop_dictionary_get(dict, "subrules");
479 	error = npf_mk_subrules(rlset, subrules, NULL);
480 	if (error) {
481 		goto out;
482 	}
483 
484 	/* Lookup the rule by name, and replace its subset (sub-rules). */
485 	obj = prop_dictionary_get(dict, "name");
486 	name = prop_string_cstring_nocopy(obj);
487 	if (npf_ruleset_replace(name, rlset) == NULL) {
488 		/* Not found. */
489 		error = ENOENT;
490 out:		/* Error path. */
491 		npf_ruleset_destroy(rlset);
492 	}
493 	prop_object_release(dict);
494 	return error;
495 }
496 
497 /*
498  * npfctl_sessions_save: construct a list of sessions and export for saving.
499  */
500 int
501 npfctl_sessions_save(u_long cmd, void *data)
502 {
503 	struct plistref *pref = data;
504 	prop_dictionary_t sesdict;
505 	prop_array_t selist, nplist;
506 	int error;
507 
508 	/* Create a dictionary and two lists. */
509 	sesdict = prop_dictionary_create();
510 	selist = prop_array_create();
511 	nplist = prop_array_create();
512 
513 	/* Save the sessions. */
514 	error = npf_session_save(selist, nplist);
515 	if (error) {
516 		goto fail;
517 	}
518 
519 	/* Set the session list, NAT policy list and export the dictionary. */
520 	prop_dictionary_set(sesdict, "session-list", selist);
521 	prop_dictionary_set(sesdict, "nat-policy-list", nplist);
522 #ifdef _KERNEL
523 	error = prop_dictionary_copyout_ioctl(pref, cmd, sesdict);
524 #else
525 	error = prop_dictionary_externalize_to_file(sesdict, data) ? 0 : errno;
526 #endif
527 fail:
528 	prop_object_release(sesdict);
529 	return error;
530 }
531 
532 /*
533  * npfctl_sessions_load: import a list of sessions, reconstruct them and load.
534  */
535 int
536 npfctl_sessions_load(u_long cmd, void *data)
537 {
538 	const struct plistref *pref = data;
539 	npf_sehash_t *sehasht = NULL;
540 	prop_dictionary_t sesdict, sedict;
541 	prop_object_iterator_t it;
542 	prop_array_t selist;
543 	int error;
544 
545 	/* Retrieve the dictionary containing session and NAT policy lists. */
546 #ifdef _KERNEL
547 	error = prop_dictionary_copyin_ioctl(pref, cmd, &sesdict);
548 	if (error)
549 		return error;
550 #else
551 	sesdict = prop_dictionary_internalize_from_file(data);
552 	if (sesdict == NULL)
553 		return EINVAL;
554 #endif
555 	/*
556 	 * Note: session objects contain the references to the NAT policy
557 	 * entries.  Therefore, no need to directly access it.
558 	 */
559 	selist = prop_dictionary_get(sesdict, "session-list");
560 	if (prop_object_type(selist) != PROP_TYPE_ARRAY) {
561 		error = EINVAL;
562 		goto fail;
563 	}
564 
565 	/* Create a session hash table. */
566 	sehasht = sess_htable_create();
567 	if (sehasht == NULL) {
568 		error = ENOMEM;
569 		goto fail;
570 	}
571 
572 	/*
573 	 * Iterate through and construct each session.
574 	 */
575 	error = 0;
576 	it = prop_array_iterator(selist);
577 	npf_core_enter();
578 	while ((sedict = prop_object_iterator_next(it)) != NULL) {
579 		/* Session - dictionary. */
580 		if (prop_object_type(sedict) != PROP_TYPE_DICTIONARY) {
581 			error = EINVAL;
582 			goto fail;
583 		}
584 		/* Construct and insert real session structure. */
585 		error = npf_session_restore(sehasht, sedict);
586 		if (error) {
587 			goto fail;
588 		}
589 	}
590 	npf_core_exit();
591 	sess_htable_reload(sehasht);
592 fail:
593 	prop_object_release(selist);
594 	if (error && sehasht) {
595 		/* Destroy session table. */
596 		sess_htable_destroy(sehasht);
597 	}
598 	return error;
599 }
600 
601 /*
602  * npfctl_table: add, remove or query entries in the specified table.
603  *
604  * For maximum performance, interface is avoiding proplib(3)'s overhead.
605  */
606 int
607 npfctl_table(void *data)
608 {
609 	npf_ioctl_table_t *nct = data;
610 	npf_tableset_t *tblset;
611 	int error;
612 
613 	npf_core_enter(); /* XXXSMP */
614 	tblset = npf_core_tableset();
615 	switch (nct->nct_action) {
616 	case NPF_IOCTL_TBLENT_ADD:
617 		error = npf_table_add_cidr(tblset, nct->nct_tid,
618 		    &nct->nct_addr, nct->nct_mask);
619 		break;
620 	case NPF_IOCTL_TBLENT_REM:
621 		error = npf_table_rem_cidr(tblset, nct->nct_tid,
622 		    &nct->nct_addr, nct->nct_mask);
623 		break;
624 	default:
625 		error = npf_table_match_addr(tblset, nct->nct_tid,
626 		    &nct->nct_addr);
627 	}
628 	npf_core_exit(); /* XXXSMP */
629 	return error;
630 }
631