xref: /netbsd-src/usr.sbin/npf/npfctl/npf_build.c (revision fdd524d4ccd2bb0c6f67401e938dabf773eb0372)
1 /*	$NetBSD: npf_build.c,v 1.40 2015/06/08 01:00:43 rmind Exp $	*/
2 
3 /*-
4  * Copyright (c) 2011-2014 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  * npfctl(8) building of the configuration.
34  */
35 
36 #include <sys/cdefs.h>
37 __RCSID("$NetBSD: npf_build.c,v 1.40 2015/06/08 01:00:43 rmind Exp $");
38 
39 #include <sys/types.h>
40 #include <sys/mman.h>
41 #include <sys/stat.h>
42 #include <netinet/tcp.h>
43 
44 #include <stdlib.h>
45 #include <inttypes.h>
46 #include <string.h>
47 #include <ctype.h>
48 #include <unistd.h>
49 #include <errno.h>
50 #include <err.h>
51 
52 #include <pcap/pcap.h>
53 #include <cdbw.h>
54 
55 #include "npfctl.h"
56 
57 #define	MAX_RULE_NESTING	16
58 
59 static nl_config_t *		npf_conf = NULL;
60 static bool			npf_debug = false;
61 static nl_rule_t *		the_rule = NULL;
62 
63 static nl_rule_t *		current_group[MAX_RULE_NESTING];
64 static unsigned			rule_nesting_level = 0;
65 static nl_rule_t *		defgroup = NULL;
66 
67 static void			npfctl_dump_bpf(struct bpf_program *);
68 
69 void
70 npfctl_config_init(bool debug)
71 {
72 	npf_conf = npf_config_create();
73 	if (npf_conf == NULL) {
74 		errx(EXIT_FAILURE, "npf_config_create failed");
75 	}
76 	npf_debug = debug;
77 	memset(current_group, 0, sizeof(current_group));
78 }
79 
80 int
81 npfctl_config_send(int fd, const char *out)
82 {
83 	int error;
84 
85 	if (out) {
86 		_npf_config_setsubmit(npf_conf, out);
87 		printf("\nSaving to %s\n", out);
88 	}
89 	if (!defgroup) {
90 		errx(EXIT_FAILURE, "default group was not defined");
91 	}
92 	npf_rule_insert(npf_conf, NULL, defgroup);
93 	error = npf_config_submit(npf_conf, fd);
94 	if (error == EEXIST) { /* XXX */
95 		errx(EXIT_FAILURE, "(re)load failed: "
96 		    "some table has a duplicate entry?");
97 	}
98 	if (error) {
99 		nl_error_t ne;
100 		_npf_config_error(npf_conf, &ne);
101 		npfctl_print_error(&ne);
102 	}
103 	if (fd) {
104 		npf_config_destroy(npf_conf);
105 	}
106 	return error;
107 }
108 
109 nl_config_t *
110 npfctl_config_ref(void)
111 {
112 	return npf_conf;
113 }
114 
115 nl_rule_t *
116 npfctl_rule_ref(void)
117 {
118 	return the_rule;
119 }
120 
121 bool
122 npfctl_debug_addif(const char *ifname)
123 {
124 	const char tname[] = "npftest";
125 	const size_t tnamelen = sizeof(tname) - 1;
126 
127 	if (npf_debug) {
128 		_npf_debug_addif(npf_conf, ifname);
129 		return strncmp(ifname, tname, tnamelen) == 0;
130 	}
131 	return 0;
132 }
133 
134 unsigned
135 npfctl_table_getid(const char *name)
136 {
137 	unsigned tid = (unsigned)-1;
138 	nl_table_t *tl;
139 
140 	/* XXX dynamic ruleset */
141 	if (!npf_conf) {
142 		return (unsigned)-1;
143 	}
144 
145 	/* XXX: Iterating all as we need to rewind for the next call. */
146 	while ((tl = npf_table_iterate(npf_conf)) != NULL) {
147 		const char *tname = npf_table_getname(tl);
148 		if (strcmp(tname, name) == 0) {
149 			tid = npf_table_getid(tl);
150 		}
151 	}
152 	return tid;
153 }
154 
155 static in_port_t
156 npfctl_get_singleport(const npfvar_t *vp)
157 {
158 	port_range_t *pr;
159 	in_port_t *port;
160 
161 	if (npfvar_get_count(vp) > 1) {
162 		yyerror("multiple ports are not valid");
163 	}
164 	pr = npfvar_get_data(vp, NPFVAR_PORT_RANGE, 0);
165 	if (pr->pr_start != pr->pr_end) {
166 		yyerror("port range is not valid");
167 	}
168 	port = &pr->pr_start;
169 	return *port;
170 }
171 
172 static fam_addr_mask_t *
173 npfctl_get_singlefam(const npfvar_t *vp)
174 {
175 	if (npfvar_get_count(vp) > 1) {
176 		yyerror("multiple addresses are not valid");
177 	}
178 	return npfvar_get_data(vp, NPFVAR_FAM, 0);
179 }
180 
181 static bool
182 npfctl_build_fam(npf_bpf_t *ctx, sa_family_t family,
183     fam_addr_mask_t *fam, int opts)
184 {
185 	/*
186 	 * If family is specified, address does not match it and the
187 	 * address is extracted from the interface, then simply ignore.
188 	 * Otherwise, address of invalid family was passed manually.
189 	 */
190 	if (family != AF_UNSPEC && family != fam->fam_family) {
191 		if (!fam->fam_ifindex) {
192 			yyerror("specified address is not of the required "
193 			    "family %d", family);
194 		}
195 		return false;
196 	}
197 
198 	family = fam->fam_family;
199 	if (family != AF_INET && family != AF_INET6) {
200 		yyerror("family %d is not supported", family);
201 	}
202 
203 	/*
204 	 * Optimise 0.0.0.0/0 case to be NOP.  Otherwise, address with
205 	 * zero mask would never match and therefore is not valid.
206 	 */
207 	if (fam->fam_mask == 0) {
208 		static const npf_addr_t zero; /* must be static */
209 
210 		if (memcmp(&fam->fam_addr, &zero, sizeof(npf_addr_t))) {
211 			yyerror("filter criterion would never match");
212 		}
213 		return false;
214 	}
215 
216 	npfctl_bpf_cidr(ctx, opts, family, &fam->fam_addr, fam->fam_mask);
217 	return true;
218 }
219 
220 static void
221 npfctl_build_vars(npf_bpf_t *ctx, sa_family_t family, npfvar_t *vars, int opts)
222 {
223 	const int type = npfvar_get_type(vars, 0);
224 	size_t i;
225 
226 	npfctl_bpf_group(ctx);
227 	for (i = 0; i < npfvar_get_count(vars); i++) {
228 		void *data = npfvar_get_data(vars, type, i);
229 		assert(data != NULL);
230 
231 		switch (type) {
232 		case NPFVAR_FAM: {
233 			fam_addr_mask_t *fam = data;
234 			npfctl_build_fam(ctx, family, fam, opts);
235 			break;
236 		}
237 		case NPFVAR_PORT_RANGE: {
238 			port_range_t *pr = data;
239 			npfctl_bpf_ports(ctx, opts, pr->pr_start, pr->pr_end);
240 			break;
241 		}
242 		case NPFVAR_TABLE: {
243 			u_int tid;
244 			memcpy(&tid, data, sizeof(u_int));
245 			npfctl_bpf_table(ctx, opts, tid);
246 			break;
247 		}
248 		default:
249 			assert(false);
250 		}
251 	}
252 	npfctl_bpf_endgroup(ctx);
253 }
254 
255 static void
256 npfctl_build_proto(npf_bpf_t *ctx, sa_family_t family, const opt_proto_t *op)
257 {
258 	const npfvar_t *popts = op->op_opts;
259 	const int proto = op->op_proto;
260 
261 	/* IP version and/or L4 protocol matching. */
262 	if (family != AF_UNSPEC || proto != -1) {
263 		npfctl_bpf_proto(ctx, family, proto);
264 	}
265 
266 	switch (proto) {
267 	case IPPROTO_TCP:
268 		/* Build TCP flags matching (optional). */
269 		if (popts) {
270 			uint8_t *tf, *tf_mask;
271 
272 			assert(npfvar_get_count(popts) == 2);
273 			tf = npfvar_get_data(popts, NPFVAR_TCPFLAG, 0);
274 			tf_mask = npfvar_get_data(popts, NPFVAR_TCPFLAG, 1);
275 			npfctl_bpf_tcpfl(ctx, *tf, *tf_mask, false);
276 		}
277 		break;
278 	case IPPROTO_ICMP:
279 	case IPPROTO_ICMPV6:
280 		/* Build ICMP/ICMPv6 type and/or code matching. */
281 		if (popts) {
282 			int *icmp_type, *icmp_code;
283 
284 			assert(npfvar_get_count(popts) == 2);
285 			icmp_type = npfvar_get_data(popts, NPFVAR_ICMP, 0);
286 			icmp_code = npfvar_get_data(popts, NPFVAR_ICMP, 1);
287 			npfctl_bpf_icmp(ctx, *icmp_type, *icmp_code);
288 		}
289 		break;
290 	default:
291 		/* No options for other protocols. */
292 		break;
293 	}
294 }
295 
296 static bool
297 npfctl_build_code(nl_rule_t *rl, sa_family_t family, const opt_proto_t *op,
298     const filt_opts_t *fopts)
299 {
300 	bool noproto, noaddrs, noports, need_tcpudp = false;
301 	const addr_port_t *apfrom = &fopts->fo_from;
302 	const addr_port_t *apto = &fopts->fo_to;
303 	const int proto = op->op_proto;
304 	npf_bpf_t *bc;
305 	size_t len;
306 
307 	/* If none specified, then no byte-code. */
308 	noproto = family == AF_UNSPEC && proto == -1 && !op->op_opts;
309 	noaddrs = !apfrom->ap_netaddr && !apto->ap_netaddr;
310 	noports = !apfrom->ap_portrange && !apto->ap_portrange;
311 	if (noproto && noaddrs && noports) {
312 		return false;
313 	}
314 
315 	/*
316 	 * Sanity check: ports can only be used with TCP or UDP protocol.
317 	 * No filter options are supported for other protocols, only the
318 	 * IP addresses are allowed.
319 	 */
320 	if (!noports) {
321 		switch (proto) {
322 		case IPPROTO_TCP:
323 		case IPPROTO_UDP:
324 			break;
325 		case -1:
326 			need_tcpudp = true;
327 			break;
328 		default:
329 			yyerror("invalid filter options for protocol %d", proto);
330 		}
331 	}
332 
333 	bc = npfctl_bpf_create();
334 
335 	/* Build layer 4 protocol blocks. */
336 	npfctl_build_proto(bc, family, op);
337 
338 	/*
339 	 * If this is a stateful rule and TCP flags are not specified,
340 	 * then add "flags S/SAFR" filter for TCP protocol case.
341 	 */
342 	if ((npf_rule_getattr(rl) & NPF_RULE_STATEFUL) != 0 &&
343 	    (proto == -1 || (proto == IPPROTO_TCP && !op->op_opts))) {
344 		npfctl_bpf_tcpfl(bc, TH_SYN,
345 		    TH_SYN | TH_ACK | TH_FIN | TH_RST, proto == -1);
346 	}
347 
348 	/* Build IP address blocks. */
349 	npfctl_build_vars(bc, family, apfrom->ap_netaddr, MATCH_SRC);
350 	npfctl_build_vars(bc, family, apto->ap_netaddr, MATCH_DST);
351 
352 	/* Build port-range blocks. */
353 	if (need_tcpudp) {
354 		/* TCP/UDP check for the ports. */
355 		npfctl_bpf_group(bc);
356 		npfctl_bpf_proto(bc, AF_UNSPEC, IPPROTO_TCP);
357 		npfctl_bpf_proto(bc, AF_UNSPEC, IPPROTO_UDP);
358 		npfctl_bpf_endgroup(bc);
359 	}
360 	npfctl_build_vars(bc, family, apfrom->ap_portrange, MATCH_SRC);
361 	npfctl_build_vars(bc, family, apto->ap_portrange, MATCH_DST);
362 
363 	/* Set the byte-code marks, if any. */
364 	const void *bmarks = npfctl_bpf_bmarks(bc, &len);
365 	if (npf_rule_setinfo(rl, bmarks, len) == -1) {
366 		errx(EXIT_FAILURE, "npf_rule_setinfo failed");
367 	}
368 
369 	/* Complete BPF byte-code and pass to the rule. */
370 	struct bpf_program *bf = npfctl_bpf_complete(bc);
371 	if (bf == NULL) {
372 		npfctl_bpf_destroy(bc);
373 		return true;
374 	}
375 	len = bf->bf_len * sizeof(struct bpf_insn);
376 
377 	if (npf_rule_setcode(rl, NPF_CODE_BPF, bf->bf_insns, len) == -1) {
378 		errx(EXIT_FAILURE, "npf_rule_setcode failed");
379 	}
380 	npfctl_dump_bpf(bf);
381 	npfctl_bpf_destroy(bc);
382 
383 	return true;
384 }
385 
386 static void
387 npfctl_build_pcap(nl_rule_t *rl, const char *filter)
388 {
389 	const size_t maxsnaplen = 64 * 1024;
390 	struct bpf_program bf;
391 	size_t len;
392 
393 	if (pcap_compile_nopcap(maxsnaplen, DLT_RAW, &bf,
394 	    filter, 1, PCAP_NETMASK_UNKNOWN) == -1) {
395 		yyerror("invalid pcap-filter(7) syntax");
396 	}
397 	len = bf.bf_len * sizeof(struct bpf_insn);
398 
399 	if (npf_rule_setcode(rl, NPF_CODE_BPF, bf.bf_insns, len) == -1) {
400 		errx(EXIT_FAILURE, "npf_rule_setcode failed");
401 	}
402 	npfctl_dump_bpf(&bf);
403 	pcap_freecode(&bf);
404 }
405 
406 static void
407 npfctl_build_rpcall(nl_rproc_t *rp, const char *name, npfvar_t *args)
408 {
409 	npf_extmod_t *extmod;
410 	nl_ext_t *extcall;
411 	int error;
412 
413 	extmod = npf_extmod_get(name, &extcall);
414 	if (extmod == NULL) {
415 		yyerror("unknown rule procedure '%s'", name);
416 	}
417 
418 	for (size_t i = 0; i < npfvar_get_count(args); i++) {
419 		const char *param, *value;
420 		proc_param_t *p;
421 
422 		p = npfvar_get_data(args, NPFVAR_PROC_PARAM, i);
423 		param = p->pp_param;
424 		value = p->pp_value;
425 
426 		error = npf_extmod_param(extmod, extcall, param, value);
427 		switch (error) {
428 		case EINVAL:
429 			yyerror("invalid parameter '%s'", param);
430 		default:
431 			break;
432 		}
433 	}
434 	error = npf_rproc_extcall(rp, extcall);
435 	if (error) {
436 		yyerror(error == EEXIST ?
437 		    "duplicate procedure call" : "unexpected error");
438 	}
439 }
440 
441 /*
442  * npfctl_build_rproc: create and insert a rule procedure.
443  */
444 void
445 npfctl_build_rproc(const char *name, npfvar_t *procs)
446 {
447 	nl_rproc_t *rp;
448 	size_t i;
449 
450 	rp = npf_rproc_create(name);
451 	if (rp == NULL) {
452 		errx(EXIT_FAILURE, "%s failed", __func__);
453 	}
454 	npf_rproc_insert(npf_conf, rp);
455 
456 	for (i = 0; i < npfvar_get_count(procs); i++) {
457 		proc_call_t *pc = npfvar_get_data(procs, NPFVAR_PROC, i);
458 		npfctl_build_rpcall(rp, pc->pc_name, pc->pc_opts);
459 	}
460 }
461 
462 void
463 npfctl_build_maprset(const char *name, int attr, const char *ifname)
464 {
465 	const int attr_di = (NPF_RULE_IN | NPF_RULE_OUT);
466 	nl_rule_t *rl;
467 
468 	/* If no direction is not specified, then both. */
469 	if ((attr & attr_di) == 0) {
470 		attr |= attr_di;
471 	}
472 	/* Allow only "in/out" attributes. */
473 	attr = NPF_RULE_GROUP | NPF_RULE_GROUP | (attr & attr_di);
474 	rl = npf_rule_create(name, attr, ifname);
475 	npf_nat_insert(npf_conf, rl, NPF_PRI_LAST);
476 }
477 
478 /*
479  * npfctl_build_group: create a group, insert into the global ruleset,
480  * update the current group pointer and increase the nesting level.
481  */
482 void
483 npfctl_build_group(const char *name, int attr, const char *ifname, bool def)
484 {
485 	const int attr_di = (NPF_RULE_IN | NPF_RULE_OUT);
486 	nl_rule_t *rl;
487 
488 	if (def || (attr & attr_di) == 0) {
489 		attr |= attr_di;
490 	}
491 
492 	rl = npf_rule_create(name, attr | NPF_RULE_GROUP, ifname);
493 	npf_rule_setprio(rl, NPF_PRI_LAST);
494 	if (def) {
495 		if (defgroup) {
496 			yyerror("multiple default groups are not valid");
497 		}
498 		if (rule_nesting_level) {
499 			yyerror("default group can only be at the top level");
500 		}
501 		defgroup = rl;
502 	} else {
503 		nl_rule_t *cg = current_group[rule_nesting_level];
504 		npf_rule_insert(npf_conf, cg, rl);
505 	}
506 
507 	/* Set the current group and increase the nesting level. */
508 	if (rule_nesting_level >= MAX_RULE_NESTING) {
509 		yyerror("rule nesting limit reached");
510 	}
511 	current_group[++rule_nesting_level] = rl;
512 }
513 
514 void
515 npfctl_build_group_end(void)
516 {
517 	assert(rule_nesting_level > 0);
518 	current_group[rule_nesting_level--] = NULL;
519 }
520 
521 /*
522  * npfctl_build_rule: create a rule, build byte-code from filter options,
523  * if any, and insert into the ruleset of current group, or set the rule.
524  */
525 void
526 npfctl_build_rule(uint32_t attr, const char *ifname, sa_family_t family,
527     const opt_proto_t *op, const filt_opts_t *fopts,
528     const char *pcap_filter, const char *rproc)
529 {
530 	nl_rule_t *rl;
531 
532 	attr |= (npf_conf ? 0 : NPF_RULE_DYNAMIC);
533 
534 	rl = npf_rule_create(NULL, attr, ifname);
535 	if (pcap_filter) {
536 		npfctl_build_pcap(rl, pcap_filter);
537 	} else {
538 		npfctl_build_code(rl, family, op, fopts);
539 	}
540 
541 	if (rproc) {
542 		npf_rule_setproc(rl, rproc);
543 	}
544 
545 	if (npf_conf) {
546 		nl_rule_t *cg = current_group[rule_nesting_level];
547 
548 		if (rproc && !npf_rproc_exists_p(npf_conf, rproc)) {
549 			yyerror("rule procedure '%s' is not defined", rproc);
550 		}
551 		assert(cg != NULL);
552 		npf_rule_setprio(rl, NPF_PRI_LAST);
553 		npf_rule_insert(npf_conf, cg, rl);
554 	} else {
555 		/* We have parsed a single rule - set it. */
556 		the_rule = rl;
557 	}
558 }
559 
560 /*
561  * npfctl_build_nat: create a single NAT policy of a specified
562  * type with a given filter options.
563  */
564 static nl_nat_t *
565 npfctl_build_nat(int type, const char *ifname, const addr_port_t *ap,
566     const filt_opts_t *fopts, u_int flags)
567 {
568 	const opt_proto_t op = { .op_proto = -1, .op_opts = NULL };
569 	fam_addr_mask_t *am = npfctl_get_singlefam(ap->ap_netaddr);
570 	in_port_t port;
571 	nl_nat_t *nat;
572 
573 	if (ap->ap_portrange) {
574 		port = npfctl_get_singleport(ap->ap_portrange);
575 		flags &= ~NPF_NAT_PORTMAP;
576 		flags |= NPF_NAT_PORTS;
577 	} else {
578 		port = 0;
579 	}
580 
581 	nat = npf_nat_create(type, flags, ifname, am->fam_family,
582 	    &am->fam_addr, am->fam_mask, port);
583 	npfctl_build_code(nat, am->fam_family, &op, fopts);
584 	npf_nat_insert(npf_conf, nat, NPF_PRI_LAST);
585 	return nat;
586 }
587 
588 /*
589  * npfctl_build_natseg: validate and create NAT policies.
590  */
591 void
592 npfctl_build_natseg(int sd, int type, const char *ifname,
593     const addr_port_t *ap1, const addr_port_t *ap2,
594     const filt_opts_t *fopts, u_int algo)
595 {
596 	fam_addr_mask_t *am1 = NULL, *am2 = NULL;
597 	nl_nat_t *nt1 = NULL, *nt2 = NULL;
598 	filt_opts_t imfopts;
599 	uint16_t adj = 0;
600 	u_int flags;
601 	bool binat;
602 
603 	assert(ifname != NULL);
604 
605 	/*
606 	 * Bi-directional NAT is a combination of inbound NAT and outbound
607 	 * NAT policies with the translation segments inverted respectively.
608 	 */
609 	binat = (NPF_NATIN | NPF_NATOUT) == type;
610 
611 	switch (sd) {
612 	case NPFCTL_NAT_DYNAMIC:
613 		/*
614 		 * Dynamic NAT: traditional NAPT is expected.  Unless it
615 		 * is bi-directional NAT, perform port mapping.
616 		 */
617 		flags = !binat ? (NPF_NAT_PORTS | NPF_NAT_PORTMAP) : 0;
618 		break;
619 	case NPFCTL_NAT_STATIC:
620 		/* Static NAT: mechanic translation. */
621 		flags = NPF_NAT_STATIC;
622 		break;
623 	default:
624 		abort();
625 	}
626 
627 	/*
628 	 * Validate the mappings and their configuration.
629 	 */
630 
631 	if ((type & NPF_NATIN) != 0) {
632 		if (!ap1->ap_netaddr)
633 			yyerror("inbound network segment is not specified");
634 		am1 = npfctl_get_singlefam(ap1->ap_netaddr);
635 	}
636 	if ((type & NPF_NATOUT) != 0) {
637 		if (!ap2->ap_netaddr)
638 			yyerror("outbound network segment is not specified");
639 		am2 = npfctl_get_singlefam(ap2->ap_netaddr);
640 	}
641 
642 	switch (algo) {
643 	case NPF_ALGO_NPT66:
644 		if (am1 == NULL || am2 == NULL)
645 			yyerror("1:1 mapping of two segments must be "
646 			    "used for NPTv6");
647 		if (am1->fam_mask != am2->fam_mask)
648 			yyerror("asymmetric translation is not supported");
649 		adj = npfctl_npt66_calcadj(am1->fam_mask,
650 		    &am1->fam_addr, &am2->fam_addr);
651 		break;
652 	default:
653 		if ((am1 && am1->fam_mask != NPF_NO_NETMASK) ||
654 		    (am2 && am2->fam_mask != NPF_NO_NETMASK))
655 			yyerror("net-to-net translation is not supported");
656 		break;
657 	}
658 
659 	/*
660 	 * If the filter criteria is not specified explicitly, apply implicit
661 	 * filtering according to the given network segments.
662 	 *
663 	 * Note: filled below, depending on the type.
664 	 */
665 	if (__predict_true(!fopts)) {
666 		fopts = &imfopts;
667 	}
668 
669 	if (type & NPF_NATIN) {
670 		memset(&imfopts, 0, sizeof(filt_opts_t));
671 		memcpy(&imfopts.fo_to, ap2, sizeof(addr_port_t));
672 		nt1 = npfctl_build_nat(NPF_NATIN, ifname, ap1, fopts, flags);
673 	}
674 	if (type & NPF_NATOUT) {
675 		memset(&imfopts, 0, sizeof(filt_opts_t));
676 		memcpy(&imfopts.fo_from, ap1, sizeof(addr_port_t));
677 		nt2 = npfctl_build_nat(NPF_NATOUT, ifname, ap2, fopts, flags);
678 	}
679 
680 	if (algo == NPF_ALGO_NPT66) {
681 		npf_nat_setnpt66(nt1, ~adj);
682 		npf_nat_setnpt66(nt2, adj);
683 	}
684 }
685 
686 /*
687  * npfctl_fill_table: fill NPF table with entries from a specified file.
688  */
689 static void
690 npfctl_fill_table(nl_table_t *tl, u_int type, const char *fname)
691 {
692 	struct cdbw *cdbw = NULL;	/* XXX: gcc */
693 	char *buf = NULL;
694 	int l = 0;
695 	FILE *fp;
696 	size_t n;
697 
698 	if (type == NPF_TABLE_CDB && (cdbw = cdbw_open()) == NULL) {
699 		err(EXIT_FAILURE, "cdbw_open");
700 	}
701 	fp = fopen(fname, "r");
702 	if (fp == NULL) {
703 		err(EXIT_FAILURE, "open '%s'", fname);
704 	}
705 	while (l++, getline(&buf, &n, fp) != -1) {
706 		fam_addr_mask_t fam;
707 		int alen;
708 
709 		if (*buf == '\n' || *buf == '#') {
710 			continue;
711 		}
712 
713 		if (!npfctl_parse_cidr(buf, &fam, &alen)) {
714 			errx(EXIT_FAILURE,
715 			    "%s:%d: invalid table entry", fname, l);
716 		}
717 		if (type != NPF_TABLE_TREE && fam.fam_mask != NPF_NO_NETMASK) {
718 			errx(EXIT_FAILURE, "%s:%d: mask used with the "
719 			    "non-tree table", fname, l);
720 		}
721 
722 		/*
723 		 * Create and add a table entry.
724 		 */
725 		if (type == NPF_TABLE_CDB) {
726 			const npf_addr_t *addr = &fam.fam_addr;
727 			if (cdbw_put(cdbw, addr, alen, addr, alen) == -1) {
728 				err(EXIT_FAILURE, "cdbw_put");
729 			}
730 		} else {
731 			npf_table_add_entry(tl, fam.fam_family,
732 			    &fam.fam_addr, fam.fam_mask);
733 		}
734 	}
735 	if (buf != NULL) {
736 		free(buf);
737 	}
738 
739 	if (type == NPF_TABLE_CDB) {
740 		struct stat sb;
741 		char sfn[32];
742 		void *cdb;
743 		int fd;
744 
745 		strlcpy(sfn, "/tmp/npfcdb.XXXXXX", sizeof(sfn));
746 		if ((fd = mkstemp(sfn)) == -1) {
747 			err(EXIT_FAILURE, "mkstemp");
748 		}
749 		unlink(sfn);
750 
751 		if (cdbw_output(cdbw, fd, "npf-table-cdb", NULL) == -1) {
752 			err(EXIT_FAILURE, "cdbw_output");
753 		}
754 		cdbw_close(cdbw);
755 
756 		if (fstat(fd, &sb) == -1) {
757 			err(EXIT_FAILURE, "fstat");
758 		}
759 		if ((cdb = mmap(NULL, sb.st_size, PROT_READ,
760 		    MAP_FILE | MAP_PRIVATE, fd, 0)) == MAP_FAILED) {
761 			err(EXIT_FAILURE, "mmap");
762 		}
763 		npf_table_setdata(tl, cdb, sb.st_size);
764 
765 		close(fd);
766 	}
767 }
768 
769 /*
770  * npfctl_build_table: create an NPF table, add to the configuration and,
771  * if required, fill with contents from a file.
772  */
773 void
774 npfctl_build_table(const char *tname, u_int type, const char *fname)
775 {
776 	static unsigned tid = 0;
777 	nl_table_t *tl;
778 
779 	tl = npf_table_create(tname, tid++, type);
780 	assert(tl != NULL);
781 
782 	if (npf_table_insert(npf_conf, tl)) {
783 		yyerror("table '%s' is already defined", tname);
784 	}
785 
786 	if (fname) {
787 		npfctl_fill_table(tl, type, fname);
788 	} else if (type == NPF_TABLE_CDB) {
789 		errx(EXIT_FAILURE, "tables of cdb type must be static");
790 	}
791 }
792 
793 /*
794  * npfctl_build_alg: create an NPF application level gateway and add it
795  * to the configuration.
796  */
797 void
798 npfctl_build_alg(const char *al_name)
799 {
800 	if (_npf_alg_load(npf_conf, al_name) != 0) {
801 		errx(EXIT_FAILURE, "ALG '%s' already loaded", al_name);
802 	}
803 }
804 
805 static void
806 npfctl_dump_bpf(struct bpf_program *bf)
807 {
808 	if (npf_debug) {
809 		extern char *yytext;
810 		extern int yylineno;
811 
812 		int rule_line = yylineno - (int)(*yytext == '\n');
813 		printf("\nRULE AT LINE %d\n", rule_line);
814 		bpf_dump(bf, 0);
815 	}
816 }
817