xref: /freebsd/sys/netgraph/ng_parse.c (revision 38f0b757fd84d17d0fc24739a7cda160c4516d81)
1 /*
2  * ng_parse.c
3  */
4 
5 /*-
6  * Copyright (c) 1999 Whistle Communications, Inc.
7  * All rights reserved.
8  *
9  * Subject to the following obligations and disclaimer of warranty, use and
10  * redistribution of this software, in source or object code forms, with or
11  * without modifications are expressly permitted by Whistle Communications;
12  * provided, however, that:
13  * 1. Any and all reproductions of the source or object code must include the
14  *    copyright notice above and the following disclaimer of warranties; and
15  * 2. No rights are granted, in any manner or form, to use Whistle
16  *    Communications, Inc. trademarks, including the mark "WHISTLE
17  *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
18  *    such appears in the above copyright notice or in the software.
19  *
20  * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
21  * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
22  * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
23  * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
24  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
25  * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
26  * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
27  * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
28  * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
29  * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
30  * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
31  * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
32  * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35  * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
36  * OF SUCH DAMAGE.
37  *
38  * Author: Archie Cobbs <archie@freebsd.org>
39  *
40  * $Whistle: ng_parse.c,v 1.3 1999/11/29 01:43:48 archie Exp $
41  * $FreeBSD$
42  */
43 
44 #include <sys/types.h>
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/kernel.h>
48 #include <sys/errno.h>
49 #include <sys/limits.h>
50 #include <sys/malloc.h>
51 #include <sys/mbuf.h>
52 #include <sys/ctype.h>
53 
54 #include <machine/stdarg.h>
55 
56 #include <net/ethernet.h>
57 
58 #include <netinet/in.h>
59 
60 #include <netgraph/ng_message.h>
61 #include <netgraph/netgraph.h>
62 #include <netgraph/ng_parse.h>
63 
64 #ifdef NG_SEPARATE_MALLOC
65 static MALLOC_DEFINE(M_NETGRAPH_PARSE, "netgraph_parse", "netgraph parse info");
66 #else
67 #define M_NETGRAPH_PARSE M_NETGRAPH
68 #endif
69 
70 /* Compute alignment for primitive integral types */
71 struct int16_temp {
72 	char	x;
73 	int16_t	y;
74 };
75 
76 struct int32_temp {
77 	char	x;
78 	int32_t	y;
79 };
80 
81 struct int64_temp {
82 	char	x;
83 	int64_t	y;
84 };
85 
86 #define INT8_ALIGNMENT		1
87 #define INT16_ALIGNMENT		((size_t)&((struct int16_temp *)0)->y)
88 #define INT32_ALIGNMENT		((size_t)&((struct int32_temp *)0)->y)
89 #define INT64_ALIGNMENT		((size_t)&((struct int64_temp *)0)->y)
90 
91 /* Output format for integral types */
92 #define INT_UNSIGNED		0
93 #define INT_SIGNED		1
94 #define INT_HEX			2
95 
96 /* Type of composite object: struct, array, or fixedarray */
97 enum comptype {
98 	CT_STRUCT,
99 	CT_ARRAY,
100 	CT_FIXEDARRAY,
101 };
102 
103 /* Composite types helper functions */
104 static int	ng_parse_composite(const struct ng_parse_type *type,
105 			const char *s, int *off, const u_char *start,
106 			u_char *const buf, int *buflen, enum comptype ctype);
107 static int	ng_unparse_composite(const struct ng_parse_type *type,
108 			const u_char *data, int *off, char *cbuf, int cbuflen,
109 			enum comptype ctype);
110 static int	ng_get_composite_elem_default(const struct ng_parse_type *type,
111 			int index, const u_char *start, u_char *buf,
112 			int *buflen, enum comptype ctype);
113 static int	ng_get_composite_len(const struct ng_parse_type *type,
114 			const u_char *start, const u_char *buf,
115 			enum comptype ctype);
116 static const	struct ng_parse_type *ng_get_composite_etype(const struct
117 			ng_parse_type *type, int index, enum comptype ctype);
118 static int	ng_parse_get_elem_pad(const struct ng_parse_type *type,
119 			int index, enum comptype ctype, int posn);
120 
121 /* Parsing helper functions */
122 static int	ng_parse_skip_value(const char *s, int off, int *lenp);
123 static int	ng_parse_append(char **cbufp, int *cbuflenp,
124 			const char *fmt, ...);
125 
126 /* Poor man's virtual method calls */
127 #define METHOD(t,m)	(ng_get_ ## m ## _method(t))
128 #define INVOKE(t,m)	(*METHOD(t,m))
129 
130 static ng_parse_t	*ng_get_parse_method(const struct ng_parse_type *t);
131 static ng_unparse_t	*ng_get_unparse_method(const struct ng_parse_type *t);
132 static ng_getDefault_t	*ng_get_getDefault_method(const
133 				struct ng_parse_type *t);
134 static ng_getAlign_t	*ng_get_getAlign_method(const struct ng_parse_type *t);
135 
136 #define ALIGNMENT(t)	(METHOD(t, getAlign) == NULL ? \
137 				0 : INVOKE(t, getAlign)(t))
138 
139 /************************************************************************
140 			PUBLIC FUNCTIONS
141  ************************************************************************/
142 
143 /*
144  * Convert an ASCII string to binary according to the supplied type descriptor
145  */
146 int
147 ng_parse(const struct ng_parse_type *type,
148 	const char *string, int *off, u_char *buf, int *buflen)
149 {
150 	return INVOKE(type, parse)(type, string, off, buf, buf, buflen);
151 }
152 
153 /*
154  * Convert binary to an ASCII string according to the supplied type descriptor
155  */
156 int
157 ng_unparse(const struct ng_parse_type *type,
158 	const u_char *data, char *cbuf, int cbuflen)
159 {
160 	int off = 0;
161 
162 	return INVOKE(type, unparse)(type, data, &off, cbuf, cbuflen);
163 }
164 
165 /*
166  * Fill in the default value according to the supplied type descriptor
167  */
168 int
169 ng_parse_getDefault(const struct ng_parse_type *type, u_char *buf, int *buflen)
170 {
171 	ng_getDefault_t *const func = METHOD(type, getDefault);
172 
173 	if (func == NULL)
174 		return (EOPNOTSUPP);
175 	return (*func)(type, buf, buf, buflen);
176 }
177 
178 
179 /************************************************************************
180 			STRUCTURE TYPE
181  ************************************************************************/
182 
183 static int
184 ng_struct_parse(const struct ng_parse_type *type,
185 	const char *s, int *off, const u_char *const start,
186 	u_char *const buf, int *buflen)
187 {
188 	return ng_parse_composite(type, s, off, start, buf, buflen, CT_STRUCT);
189 }
190 
191 static int
192 ng_struct_unparse(const struct ng_parse_type *type,
193 	const u_char *data, int *off, char *cbuf, int cbuflen)
194 {
195 	return ng_unparse_composite(type, data, off, cbuf, cbuflen, CT_STRUCT);
196 }
197 
198 static int
199 ng_struct_getDefault(const struct ng_parse_type *type,
200 	const u_char *const start, u_char *buf, int *buflen)
201 {
202 	int off = 0;
203 
204 	return ng_parse_composite(type,
205 	    "{}", &off, start, buf, buflen, CT_STRUCT);
206 }
207 
208 static int
209 ng_struct_getAlign(const struct ng_parse_type *type)
210 {
211 	const struct ng_parse_struct_field *field;
212 	int align = 0;
213 
214 	for (field = type->info; field->name != NULL; field++) {
215 		int falign = ALIGNMENT(field->type);
216 
217 		if (falign > align)
218 			align = falign;
219 	}
220 	return align;
221 }
222 
223 const struct ng_parse_type ng_parse_struct_type = {
224 	NULL,
225 	NULL,
226 	NULL,
227 	ng_struct_parse,
228 	ng_struct_unparse,
229 	ng_struct_getDefault,
230 	ng_struct_getAlign
231 };
232 
233 /************************************************************************
234 			FIXED LENGTH ARRAY TYPE
235  ************************************************************************/
236 
237 static int
238 ng_fixedarray_parse(const struct ng_parse_type *type,
239 	const char *s, int *off, const u_char *const start,
240 	u_char *const buf, int *buflen)
241 {
242 	return ng_parse_composite(type,
243 	    s, off, start, buf, buflen, CT_FIXEDARRAY);
244 }
245 
246 static int
247 ng_fixedarray_unparse(const struct ng_parse_type *type,
248 	const u_char *data, int *off, char *cbuf, int cbuflen)
249 {
250 	return ng_unparse_composite(type,
251 		data, off, cbuf, cbuflen, CT_FIXEDARRAY);
252 }
253 
254 static int
255 ng_fixedarray_getDefault(const struct ng_parse_type *type,
256 	const u_char *const start, u_char *buf, int *buflen)
257 {
258 	int off = 0;
259 
260 	return ng_parse_composite(type,
261 	    "[]", &off, start, buf, buflen, CT_FIXEDARRAY);
262 }
263 
264 static int
265 ng_fixedarray_getAlign(const struct ng_parse_type *type)
266 {
267 	const struct ng_parse_fixedarray_info *fi = type->info;
268 
269 	return ALIGNMENT(fi->elementType);
270 }
271 
272 const struct ng_parse_type ng_parse_fixedarray_type = {
273 	NULL,
274 	NULL,
275 	NULL,
276 	ng_fixedarray_parse,
277 	ng_fixedarray_unparse,
278 	ng_fixedarray_getDefault,
279 	ng_fixedarray_getAlign
280 };
281 
282 /************************************************************************
283 			VARIABLE LENGTH ARRAY TYPE
284  ************************************************************************/
285 
286 static int
287 ng_array_parse(const struct ng_parse_type *type,
288 	const char *s, int *off, const u_char *const start,
289 	u_char *const buf, int *buflen)
290 {
291 	return ng_parse_composite(type, s, off, start, buf, buflen, CT_ARRAY);
292 }
293 
294 static int
295 ng_array_unparse(const struct ng_parse_type *type,
296 	const u_char *data, int *off, char *cbuf, int cbuflen)
297 {
298 	return ng_unparse_composite(type, data, off, cbuf, cbuflen, CT_ARRAY);
299 }
300 
301 static int
302 ng_array_getDefault(const struct ng_parse_type *type,
303 	const u_char *const start, u_char *buf, int *buflen)
304 {
305 	int off = 0;
306 
307 	return ng_parse_composite(type,
308 	    "[]", &off, start, buf, buflen, CT_ARRAY);
309 }
310 
311 static int
312 ng_array_getAlign(const struct ng_parse_type *type)
313 {
314 	const struct ng_parse_array_info *ai = type->info;
315 
316 	return ALIGNMENT(ai->elementType);
317 }
318 
319 const struct ng_parse_type ng_parse_array_type = {
320 	NULL,
321 	NULL,
322 	NULL,
323 	ng_array_parse,
324 	ng_array_unparse,
325 	ng_array_getDefault,
326 	ng_array_getAlign
327 };
328 
329 /************************************************************************
330 				INT8 TYPE
331  ************************************************************************/
332 
333 static int
334 ng_int8_parse(const struct ng_parse_type *type,
335 	const char *s, int *off, const u_char *const start,
336 	u_char *const buf, int *buflen)
337 {
338 	long val;
339 	int8_t val8;
340 	char *eptr;
341 
342 	val = strtol(s + *off, &eptr, 0);
343 	if (val < (int8_t)0x80 || val > (u_int8_t)0xff || eptr == s + *off)
344 		return (EINVAL);
345 	*off = eptr - s;
346 	val8 = (int8_t)val;
347 	bcopy(&val8, buf, sizeof(int8_t));
348 	*buflen = sizeof(int8_t);
349 	return (0);
350 }
351 
352 static int
353 ng_int8_unparse(const struct ng_parse_type *type,
354 	const u_char *data, int *off, char *cbuf, int cbuflen)
355 {
356 	const char *fmt;
357 	int fval;
358 	int error;
359 	int8_t val;
360 
361 	bcopy(data + *off, &val, sizeof(int8_t));
362 	switch ((intptr_t)type->info) {
363 	case INT_SIGNED:
364 		fmt = "%d";
365 		fval = val;
366 		break;
367 	case INT_UNSIGNED:
368 		fmt = "%u";
369 		fval = (u_int8_t)val;
370 		break;
371 	case INT_HEX:
372 		fmt = "0x%x";
373 		fval = (u_int8_t)val;
374 		break;
375 	default:
376 		panic("%s: unknown type", __func__);
377 	}
378 	if ((error = ng_parse_append(&cbuf, &cbuflen, fmt, fval)) != 0)
379 		return (error);
380 	*off += sizeof(int8_t);
381 	return (0);
382 }
383 
384 static int
385 ng_int8_getDefault(const struct ng_parse_type *type,
386 	const u_char *const start, u_char *buf, int *buflen)
387 {
388 	int8_t val;
389 
390 	if (*buflen < sizeof(int8_t))
391 		return (ERANGE);
392 	val = 0;
393 	bcopy(&val, buf, sizeof(int8_t));
394 	*buflen = sizeof(int8_t);
395 	return (0);
396 }
397 
398 static int
399 ng_int8_getAlign(const struct ng_parse_type *type)
400 {
401 	return INT8_ALIGNMENT;
402 }
403 
404 const struct ng_parse_type ng_parse_int8_type = {
405 	NULL,
406 	(void *)INT_SIGNED,
407 	NULL,
408 	ng_int8_parse,
409 	ng_int8_unparse,
410 	ng_int8_getDefault,
411 	ng_int8_getAlign
412 };
413 
414 const struct ng_parse_type ng_parse_uint8_type = {
415 	&ng_parse_int8_type,
416 	(void *)INT_UNSIGNED
417 };
418 
419 const struct ng_parse_type ng_parse_hint8_type = {
420 	&ng_parse_int8_type,
421 	(void *)INT_HEX
422 };
423 
424 /************************************************************************
425 				INT16 TYPE
426  ************************************************************************/
427 
428 static int
429 ng_int16_parse(const struct ng_parse_type *type,
430 	const char *s, int *off, const u_char *const start,
431 	u_char *const buf, int *buflen)
432 {
433 	long val;
434 	int16_t val16;
435 	char *eptr;
436 
437 	val = strtol(s + *off, &eptr, 0);
438 	if (val < (int16_t)0x8000
439 	    || val > (u_int16_t)0xffff || eptr == s + *off)
440 		return (EINVAL);
441 	*off = eptr - s;
442 	val16 = (int16_t)val;
443 	bcopy(&val16, buf, sizeof(int16_t));
444 	*buflen = sizeof(int16_t);
445 	return (0);
446 }
447 
448 static int
449 ng_int16_unparse(const struct ng_parse_type *type,
450 	const u_char *data, int *off, char *cbuf, int cbuflen)
451 {
452 	const char *fmt;
453 	int fval;
454 	int error;
455 	int16_t val;
456 
457 	bcopy(data + *off, &val, sizeof(int16_t));
458 	switch ((intptr_t)type->info) {
459 	case INT_SIGNED:
460 		fmt = "%d";
461 		fval = val;
462 		break;
463 	case INT_UNSIGNED:
464 		fmt = "%u";
465 		fval = (u_int16_t)val;
466 		break;
467 	case INT_HEX:
468 		fmt = "0x%x";
469 		fval = (u_int16_t)val;
470 		break;
471 	default:
472 		panic("%s: unknown type", __func__);
473 	}
474 	if ((error = ng_parse_append(&cbuf, &cbuflen, fmt, fval)) != 0)
475 		return (error);
476 	*off += sizeof(int16_t);
477 	return (0);
478 }
479 
480 static int
481 ng_int16_getDefault(const struct ng_parse_type *type,
482 	const u_char *const start, u_char *buf, int *buflen)
483 {
484 	int16_t val;
485 
486 	if (*buflen < sizeof(int16_t))
487 		return (ERANGE);
488 	val = 0;
489 	bcopy(&val, buf, sizeof(int16_t));
490 	*buflen = sizeof(int16_t);
491 	return (0);
492 }
493 
494 static int
495 ng_int16_getAlign(const struct ng_parse_type *type)
496 {
497 	return INT16_ALIGNMENT;
498 }
499 
500 const struct ng_parse_type ng_parse_int16_type = {
501 	NULL,
502 	(void *)INT_SIGNED,
503 	NULL,
504 	ng_int16_parse,
505 	ng_int16_unparse,
506 	ng_int16_getDefault,
507 	ng_int16_getAlign
508 };
509 
510 const struct ng_parse_type ng_parse_uint16_type = {
511 	&ng_parse_int16_type,
512 	(void *)INT_UNSIGNED
513 };
514 
515 const struct ng_parse_type ng_parse_hint16_type = {
516 	&ng_parse_int16_type,
517 	(void *)INT_HEX
518 };
519 
520 /************************************************************************
521 				INT32 TYPE
522  ************************************************************************/
523 
524 static int
525 ng_int32_parse(const struct ng_parse_type *type,
526 	const char *s, int *off, const u_char *const start,
527 	u_char *const buf, int *buflen)
528 {
529 	long val;			/* assumes long is at least 32 bits */
530 	int32_t val32;
531 	char *eptr;
532 
533 	if ((intptr_t)type->info == INT_SIGNED)
534 		val = strtol(s + *off, &eptr, 0);
535 	else
536 		val = strtoul(s + *off, &eptr, 0);
537 	if (val < (int32_t)0x80000000
538 	    || val > (u_int32_t)0xffffffff || eptr == s + *off)
539 		return (EINVAL);
540 	*off = eptr - s;
541 	val32 = (int32_t)val;
542 	bcopy(&val32, buf, sizeof(int32_t));
543 	*buflen = sizeof(int32_t);
544 	return (0);
545 }
546 
547 static int
548 ng_int32_unparse(const struct ng_parse_type *type,
549 	const u_char *data, int *off, char *cbuf, int cbuflen)
550 {
551 	const char *fmt;
552 	long fval;
553 	int error;
554 	int32_t val;
555 
556 	bcopy(data + *off, &val, sizeof(int32_t));
557 	switch ((intptr_t)type->info) {
558 	case INT_SIGNED:
559 		fmt = "%ld";
560 		fval = val;
561 		break;
562 	case INT_UNSIGNED:
563 		fmt = "%lu";
564 		fval = (u_int32_t)val;
565 		break;
566 	case INT_HEX:
567 		fmt = "0x%lx";
568 		fval = (u_int32_t)val;
569 		break;
570 	default:
571 		panic("%s: unknown type", __func__);
572 	}
573 	if ((error = ng_parse_append(&cbuf, &cbuflen, fmt, fval)) != 0)
574 		return (error);
575 	*off += sizeof(int32_t);
576 	return (0);
577 }
578 
579 static int
580 ng_int32_getDefault(const struct ng_parse_type *type,
581 	const u_char *const start, u_char *buf, int *buflen)
582 {
583 	int32_t val;
584 
585 	if (*buflen < sizeof(int32_t))
586 		return (ERANGE);
587 	val = 0;
588 	bcopy(&val, buf, sizeof(int32_t));
589 	*buflen = sizeof(int32_t);
590 	return (0);
591 }
592 
593 static int
594 ng_int32_getAlign(const struct ng_parse_type *type)
595 {
596 	return INT32_ALIGNMENT;
597 }
598 
599 const struct ng_parse_type ng_parse_int32_type = {
600 	NULL,
601 	(void *)INT_SIGNED,
602 	NULL,
603 	ng_int32_parse,
604 	ng_int32_unparse,
605 	ng_int32_getDefault,
606 	ng_int32_getAlign
607 };
608 
609 const struct ng_parse_type ng_parse_uint32_type = {
610 	&ng_parse_int32_type,
611 	(void *)INT_UNSIGNED
612 };
613 
614 const struct ng_parse_type ng_parse_hint32_type = {
615 	&ng_parse_int32_type,
616 	(void *)INT_HEX
617 };
618 
619 /************************************************************************
620 				INT64 TYPE
621  ************************************************************************/
622 
623 static int
624 ng_int64_parse(const struct ng_parse_type *type,
625 	const char *s, int *off, const u_char *const start,
626 	u_char *const buf, int *buflen)
627 {
628 	quad_t val;
629 	int64_t val64;
630 	char *eptr;
631 
632 	val = strtoq(s + *off, &eptr, 0);
633 	if (eptr == s + *off)
634 		return (EINVAL);
635 	*off = eptr - s;
636 	val64 = (int64_t)val;
637 	bcopy(&val64, buf, sizeof(int64_t));
638 	*buflen = sizeof(int64_t);
639 	return (0);
640 }
641 
642 static int
643 ng_int64_unparse(const struct ng_parse_type *type,
644 	const u_char *data, int *off, char *cbuf, int cbuflen)
645 {
646 	const char *fmt;
647 	long long fval;
648 	int64_t val;
649 	int error;
650 
651 	bcopy(data + *off, &val, sizeof(int64_t));
652 	switch ((intptr_t)type->info) {
653 	case INT_SIGNED:
654 		fmt = "%lld";
655 		fval = val;
656 		break;
657 	case INT_UNSIGNED:
658 		fmt = "%llu";
659 		fval = (u_int64_t)val;
660 		break;
661 	case INT_HEX:
662 		fmt = "0x%llx";
663 		fval = (u_int64_t)val;
664 		break;
665 	default:
666 		panic("%s: unknown type", __func__);
667 	}
668 	if ((error = ng_parse_append(&cbuf, &cbuflen, fmt, fval)) != 0)
669 		return (error);
670 	*off += sizeof(int64_t);
671 	return (0);
672 }
673 
674 static int
675 ng_int64_getDefault(const struct ng_parse_type *type,
676 	const u_char *const start, u_char *buf, int *buflen)
677 {
678 	int64_t val;
679 
680 	if (*buflen < sizeof(int64_t))
681 		return (ERANGE);
682 	val = 0;
683 	bcopy(&val, buf, sizeof(int64_t));
684 	*buflen = sizeof(int64_t);
685 	return (0);
686 }
687 
688 static int
689 ng_int64_getAlign(const struct ng_parse_type *type)
690 {
691 	return INT64_ALIGNMENT;
692 }
693 
694 const struct ng_parse_type ng_parse_int64_type = {
695 	NULL,
696 	(void *)INT_SIGNED,
697 	NULL,
698 	ng_int64_parse,
699 	ng_int64_unparse,
700 	ng_int64_getDefault,
701 	ng_int64_getAlign
702 };
703 
704 const struct ng_parse_type ng_parse_uint64_type = {
705 	&ng_parse_int64_type,
706 	(void *)INT_UNSIGNED
707 };
708 
709 const struct ng_parse_type ng_parse_hint64_type = {
710 	&ng_parse_int64_type,
711 	(void *)INT_HEX
712 };
713 
714 /************************************************************************
715 				STRING TYPE
716  ************************************************************************/
717 
718 static int
719 ng_string_parse(const struct ng_parse_type *type,
720 	const char *s, int *off, const u_char *const start,
721 	u_char *const buf, int *buflen)
722 {
723 	char *sval;
724 	int len;
725 	int slen;
726 
727 	if ((sval = ng_get_string_token(s, off, &len, &slen)) == NULL)
728 		return (EINVAL);
729 	*off += len;
730 	bcopy(sval, buf, slen + 1);
731 	free(sval, M_NETGRAPH_PARSE);
732 	*buflen = slen + 1;
733 	return (0);
734 }
735 
736 static int
737 ng_string_unparse(const struct ng_parse_type *type,
738 	const u_char *data, int *off, char *cbuf, int cbuflen)
739 {
740 	const char *const raw = (const char *)data + *off;
741 	char *const s = ng_encode_string(raw, strlen(raw));
742 	int error;
743 
744 	if (s == NULL)
745 		return (ENOMEM);
746 	if ((error = ng_parse_append(&cbuf, &cbuflen, "%s", s)) != 0) {
747 		free(s, M_NETGRAPH_PARSE);
748 		return (error);
749 	}
750 	*off += strlen(raw) + 1;
751 	free(s, M_NETGRAPH_PARSE);
752 	return (0);
753 }
754 
755 static int
756 ng_string_getDefault(const struct ng_parse_type *type,
757 	const u_char *const start, u_char *buf, int *buflen)
758 {
759 
760 	if (*buflen < 1)
761 		return (ERANGE);
762 	buf[0] = (u_char)'\0';
763 	*buflen = 1;
764 	return (0);
765 }
766 
767 const struct ng_parse_type ng_parse_string_type = {
768 	NULL,
769 	NULL,
770 	NULL,
771 	ng_string_parse,
772 	ng_string_unparse,
773 	ng_string_getDefault,
774 	NULL
775 };
776 
777 /************************************************************************
778 			FIXED BUFFER STRING TYPE
779  ************************************************************************/
780 
781 static int
782 ng_fixedstring_parse(const struct ng_parse_type *type,
783 	const char *s, int *off, const u_char *const start,
784 	u_char *const buf, int *buflen)
785 {
786 	const struct ng_parse_fixedstring_info *const fi = type->info;
787 	char *sval;
788 	int len;
789 	int slen;
790 
791 	if ((sval = ng_get_string_token(s, off, &len, &slen)) == NULL)
792 		return (EINVAL);
793 	if (slen + 1 > fi->bufSize) {
794 		free(sval, M_NETGRAPH_PARSE);
795 		return (E2BIG);
796 	}
797 	*off += len;
798 	bcopy(sval, buf, slen);
799 	free(sval, M_NETGRAPH_PARSE);
800 	bzero(buf + slen, fi->bufSize - slen);
801 	*buflen = fi->bufSize;
802 	return (0);
803 }
804 
805 static int
806 ng_fixedstring_unparse(const struct ng_parse_type *type,
807 	const u_char *data, int *off, char *cbuf, int cbuflen)
808 {
809 	const struct ng_parse_fixedstring_info *const fi = type->info;
810 	int error, temp = *off;
811 
812 	if ((error = ng_string_unparse(type, data, &temp, cbuf, cbuflen)) != 0)
813 		return (error);
814 	*off += fi->bufSize;
815 	return (0);
816 }
817 
818 static int
819 ng_fixedstring_getDefault(const struct ng_parse_type *type,
820 	const u_char *const start, u_char *buf, int *buflen)
821 {
822 	const struct ng_parse_fixedstring_info *const fi = type->info;
823 
824 	if (*buflen < fi->bufSize)
825 		return (ERANGE);
826 	bzero(buf, fi->bufSize);
827 	*buflen = fi->bufSize;
828 	return (0);
829 }
830 
831 const struct ng_parse_type ng_parse_fixedstring_type = {
832 	NULL,
833 	NULL,
834 	NULL,
835 	ng_fixedstring_parse,
836 	ng_fixedstring_unparse,
837 	ng_fixedstring_getDefault,
838 	NULL
839 };
840 
841 const struct ng_parse_fixedstring_info ng_parse_nodebuf_info = {
842 	NG_NODESIZ
843 };
844 const struct ng_parse_type ng_parse_nodebuf_type = {
845 	&ng_parse_fixedstring_type,
846 	&ng_parse_nodebuf_info
847 };
848 
849 const struct ng_parse_fixedstring_info ng_parse_hookbuf_info = {
850 	NG_HOOKSIZ
851 };
852 const struct ng_parse_type ng_parse_hookbuf_type = {
853 	&ng_parse_fixedstring_type,
854 	&ng_parse_hookbuf_info
855 };
856 
857 const struct ng_parse_fixedstring_info ng_parse_pathbuf_info = {
858 	NG_PATHSIZ
859 };
860 const struct ng_parse_type ng_parse_pathbuf_type = {
861 	&ng_parse_fixedstring_type,
862 	&ng_parse_pathbuf_info
863 };
864 
865 const struct ng_parse_fixedstring_info ng_parse_typebuf_info = {
866 	NG_TYPESIZ
867 };
868 const struct ng_parse_type ng_parse_typebuf_type = {
869 	&ng_parse_fixedstring_type,
870 	&ng_parse_typebuf_info
871 };
872 
873 const struct ng_parse_fixedstring_info ng_parse_cmdbuf_info = {
874 	NG_CMDSTRSIZ
875 };
876 const struct ng_parse_type ng_parse_cmdbuf_type = {
877 	&ng_parse_fixedstring_type,
878 	&ng_parse_cmdbuf_info
879 };
880 
881 /************************************************************************
882 			EXPLICITLY SIZED STRING TYPE
883  ************************************************************************/
884 
885 static int
886 ng_sizedstring_parse(const struct ng_parse_type *type,
887 	const char *s, int *off, const u_char *const start,
888 	u_char *const buf, int *buflen)
889 {
890 	char *sval;
891 	int len;
892 	int slen;
893 
894 	if ((sval = ng_get_string_token(s, off, &len, &slen)) == NULL)
895 		return (EINVAL);
896 	if (slen > USHRT_MAX) {
897 		free(sval, M_NETGRAPH_PARSE);
898 		return (EINVAL);
899 	}
900 	*off += len;
901 	*((u_int16_t *)buf) = (u_int16_t)slen;
902 	bcopy(sval, buf + 2, slen);
903 	free(sval, M_NETGRAPH_PARSE);
904 	*buflen = 2 + slen;
905 	return (0);
906 }
907 
908 static int
909 ng_sizedstring_unparse(const struct ng_parse_type *type,
910 	const u_char *data, int *off, char *cbuf, int cbuflen)
911 {
912 	const char *const raw = (const char *)data + *off + 2;
913 	const int slen = *((const u_int16_t *)(data + *off));
914 	char *const s = ng_encode_string(raw, slen);
915 	int error;
916 
917 	if (s == NULL)
918 		return (ENOMEM);
919 	if ((error = ng_parse_append(&cbuf, &cbuflen, "%s", s)) != 0) {
920 		free(s, M_NETGRAPH_PARSE);
921 		return (error);
922 	}
923 	free(s, M_NETGRAPH_PARSE);
924 	*off += slen + 2;
925 	return (0);
926 }
927 
928 static int
929 ng_sizedstring_getDefault(const struct ng_parse_type *type,
930 	const u_char *const start, u_char *buf, int *buflen)
931 {
932 	if (*buflen < 2)
933 		return (ERANGE);
934 	bzero(buf, 2);
935 	*buflen = 2;
936 	return (0);
937 }
938 
939 const struct ng_parse_type ng_parse_sizedstring_type = {
940 	NULL,
941 	NULL,
942 	NULL,
943 	ng_sizedstring_parse,
944 	ng_sizedstring_unparse,
945 	ng_sizedstring_getDefault,
946 	NULL
947 };
948 
949 /************************************************************************
950 			IP ADDRESS TYPE
951  ************************************************************************/
952 
953 static int
954 ng_ipaddr_parse(const struct ng_parse_type *type,
955 	const char *s, int *off, const u_char *const start,
956 	u_char *const buf, int *buflen)
957 {
958 	int i, error;
959 
960 	for (i = 0; i < 4; i++) {
961 		if ((error = ng_int8_parse(&ng_parse_int8_type,
962 		    s, off, start, buf + i, buflen)) != 0)
963 			return (error);
964 		if (i < 3 && s[*off] != '.')
965 			return (EINVAL);
966 		(*off)++;
967 	}
968 	*buflen = 4;
969 	return (0);
970 }
971 
972 static int
973 ng_ipaddr_unparse(const struct ng_parse_type *type,
974 	const u_char *data, int *off, char *cbuf, int cbuflen)
975 {
976 	struct in_addr ip;
977 	int error;
978 
979 	bcopy(data + *off, &ip, sizeof(ip));
980 	if ((error = ng_parse_append(&cbuf, &cbuflen, "%d.%d.%d.%d",
981 	    ((u_char *)&ip)[0], ((u_char *)&ip)[1],
982 	    ((u_char *)&ip)[2], ((u_char *)&ip)[3])) != 0)
983 		return (error);
984 	*off += sizeof(ip);
985 	return (0);
986 }
987 
988 static int
989 ng_ipaddr_getDefault(const struct ng_parse_type *type,
990 	const u_char *const start, u_char *buf, int *buflen)
991 {
992 	struct in_addr ip = { 0 };
993 
994 	if (*buflen < sizeof(ip))
995 		return (ERANGE);
996 	bcopy(&ip, buf, sizeof(ip));
997 	*buflen = sizeof(ip);
998 	return (0);
999 }
1000 
1001 const struct ng_parse_type ng_parse_ipaddr_type = {
1002 	NULL,
1003 	NULL,
1004 	NULL,
1005 	ng_ipaddr_parse,
1006 	ng_ipaddr_unparse,
1007 	ng_ipaddr_getDefault,
1008 	ng_int32_getAlign
1009 };
1010 
1011 /************************************************************************
1012 			ETHERNET ADDRESS TYPE
1013  ************************************************************************/
1014 
1015 static int
1016 ng_enaddr_parse(const struct ng_parse_type *type,
1017 	const char *s, int *const off, const u_char *const start,
1018 	u_char *const buf, int *const buflen)
1019 {
1020 	char *eptr;
1021 	u_long val;
1022 	int i;
1023 
1024 	if (*buflen < ETHER_ADDR_LEN)
1025 		return (ERANGE);
1026 	for (i = 0; i < ETHER_ADDR_LEN; i++) {
1027 		val = strtoul(s + *off, &eptr, 16);
1028 		if (val > 0xff || eptr == s + *off)
1029 			return (EINVAL);
1030 		buf[i] = (u_char)val;
1031 		*off = (eptr - s);
1032 		if (i < ETHER_ADDR_LEN - 1) {
1033 			if (*eptr != ':')
1034 				return (EINVAL);
1035 			(*off)++;
1036 		}
1037 	}
1038 	*buflen = ETHER_ADDR_LEN;
1039 	return (0);
1040 }
1041 
1042 static int
1043 ng_enaddr_unparse(const struct ng_parse_type *type,
1044 	const u_char *data, int *off, char *cbuf, int cbuflen)
1045 {
1046 	int len;
1047 
1048 	len = snprintf(cbuf, cbuflen, "%02x:%02x:%02x:%02x:%02x:%02x",
1049 	    data[*off], data[*off + 1], data[*off + 2],
1050 	    data[*off + 3], data[*off + 4], data[*off + 5]);
1051 	if (len >= cbuflen)
1052 		return (ERANGE);
1053 	*off += ETHER_ADDR_LEN;
1054 	return (0);
1055 }
1056 
1057 const struct ng_parse_type ng_parse_enaddr_type = {
1058 	NULL,
1059 	NULL,
1060 	NULL,
1061 	ng_enaddr_parse,
1062 	ng_enaddr_unparse,
1063 	NULL,
1064 	0
1065 };
1066 
1067 /************************************************************************
1068 			BYTE ARRAY TYPE
1069  ************************************************************************/
1070 
1071 /* Get the length of a byte array */
1072 static int
1073 ng_parse_bytearray_subtype_getLength(const struct ng_parse_type *type,
1074 	const u_char *start, const u_char *buf)
1075 {
1076 	ng_parse_array_getLength_t *const getLength = type->private;
1077 
1078 	return (*getLength)(type, start, buf);
1079 }
1080 
1081 /* Byte array element type is hex int8 */
1082 static const struct ng_parse_array_info ng_parse_bytearray_subtype_info = {
1083 	&ng_parse_hint8_type,
1084 	&ng_parse_bytearray_subtype_getLength,
1085 	NULL
1086 };
1087 static const struct ng_parse_type ng_parse_bytearray_subtype = {
1088 	&ng_parse_array_type,
1089 	&ng_parse_bytearray_subtype_info
1090 };
1091 
1092 static int
1093 ng_bytearray_parse(const struct ng_parse_type *type,
1094 	const char *s, int *off, const u_char *const start,
1095 	u_char *const buf, int *buflen)
1096 {
1097 	char *str;
1098 	int toklen;
1099 	int slen;
1100 
1101 	/* We accept either an array of bytes or a string constant */
1102 	if ((str = ng_get_string_token(s, off, &toklen, &slen)) != NULL) {
1103 		ng_parse_array_getLength_t *const getLength = type->info;
1104 		int arraylen;
1105 
1106 		arraylen = (*getLength)(type, start, buf);
1107 		if (arraylen > *buflen) {
1108 			free(str, M_NETGRAPH_PARSE);
1109 			return (ERANGE);
1110 		}
1111 		if (slen > arraylen) {
1112 			free(str, M_NETGRAPH_PARSE);
1113 			return (E2BIG);
1114 		}
1115 		bcopy(str, buf, slen);
1116 		bzero(buf + slen, arraylen - slen);
1117 		free(str, M_NETGRAPH_PARSE);
1118 		*off += toklen;
1119 		*buflen = arraylen;
1120 		return (0);
1121 	} else {
1122 		struct ng_parse_type subtype;
1123 
1124 		subtype = ng_parse_bytearray_subtype;
1125 		*(const void **)&subtype.private = type->info;
1126 		return ng_array_parse(&subtype, s, off, start, buf, buflen);
1127 	}
1128 }
1129 
1130 static int
1131 ng_bytearray_unparse(const struct ng_parse_type *type,
1132 	const u_char *data, int *off, char *cbuf, int cbuflen)
1133 {
1134 	struct ng_parse_type subtype;
1135 
1136 	subtype = ng_parse_bytearray_subtype;
1137 	*(const void **)&subtype.private = type->info;
1138 	return ng_array_unparse(&subtype, data, off, cbuf, cbuflen);
1139 }
1140 
1141 static int
1142 ng_bytearray_getDefault(const struct ng_parse_type *type,
1143 	const u_char *const start, u_char *buf, int *buflen)
1144 {
1145 	struct ng_parse_type subtype;
1146 
1147 	subtype = ng_parse_bytearray_subtype;
1148 	*(const void **)&subtype.private = type->info;
1149 	return ng_array_getDefault(&subtype, start, buf, buflen);
1150 }
1151 
1152 const struct ng_parse_type ng_parse_bytearray_type = {
1153 	NULL,
1154 	NULL,
1155 	NULL,
1156 	ng_bytearray_parse,
1157 	ng_bytearray_unparse,
1158 	ng_bytearray_getDefault,
1159 	NULL
1160 };
1161 
1162 /************************************************************************
1163 			STRUCT NG_MESG TYPE
1164  ************************************************************************/
1165 
1166 /* Get msg->header.arglen when "buf" is pointing to msg->data */
1167 static int
1168 ng_parse_ng_mesg_getLength(const struct ng_parse_type *type,
1169 	const u_char *start, const u_char *buf)
1170 {
1171 	const struct ng_mesg *msg;
1172 
1173 	msg = (const struct ng_mesg *)(buf - sizeof(*msg));
1174 	return msg->header.arglen;
1175 }
1176 
1177 /* Type for the variable length data portion of a struct ng_mesg */
1178 static const struct ng_parse_type ng_msg_data_type = {
1179 	&ng_parse_bytearray_type,
1180 	&ng_parse_ng_mesg_getLength
1181 };
1182 
1183 /* Type for the entire struct ng_mesg header with data section */
1184 static const struct ng_parse_struct_field ng_parse_ng_mesg_type_fields[]
1185 	= NG_GENERIC_NG_MESG_INFO(&ng_msg_data_type);
1186 const struct ng_parse_type ng_parse_ng_mesg_type = {
1187 	&ng_parse_struct_type,
1188 	&ng_parse_ng_mesg_type_fields,
1189 };
1190 
1191 /************************************************************************
1192 			COMPOSITE HELPER ROUTINES
1193  ************************************************************************/
1194 
1195 /*
1196  * Convert a structure or array from ASCII to binary
1197  */
1198 static int
1199 ng_parse_composite(const struct ng_parse_type *type, const char *s,
1200 	int *off, const u_char *const start, u_char *const buf, int *buflen,
1201 	const enum comptype ctype)
1202 {
1203 	const int num = ng_get_composite_len(type, start, buf, ctype);
1204 	int nextIndex = 0;		/* next implicit array index */
1205 	u_int index;			/* field or element index */
1206 	int *foff;			/* field value offsets in string */
1207 	int align, len, blen, error = 0;
1208 
1209 	/* Initialize */
1210 	foff = malloc(num * sizeof(*foff), M_NETGRAPH_PARSE, M_NOWAIT | M_ZERO);
1211 	if (foff == NULL) {
1212 		error = ENOMEM;
1213 		goto done;
1214 	}
1215 
1216 	/* Get opening brace/bracket */
1217 	if (ng_parse_get_token(s, off, &len)
1218 	    != (ctype == CT_STRUCT ? T_LBRACE : T_LBRACKET)) {
1219 		error = EINVAL;
1220 		goto done;
1221 	}
1222 	*off += len;
1223 
1224 	/* Get individual element value positions in the string */
1225 	for (;;) {
1226 		enum ng_parse_token tok;
1227 
1228 		/* Check for closing brace/bracket */
1229 		tok = ng_parse_get_token(s, off, &len);
1230 		if (tok == (ctype == CT_STRUCT ? T_RBRACE : T_RBRACKET)) {
1231 			*off += len;
1232 			break;
1233 		}
1234 
1235 		/* For arrays, the 'name' (ie, index) is optional, so
1236 		   distinguish name from values by seeing if the next
1237 		   token is an equals sign */
1238 		if (ctype != CT_STRUCT) {
1239 			u_long ul;
1240 			int len2, off2;
1241 			char *eptr;
1242 
1243 			/* If an opening brace/bracket, index is implied */
1244 			if (tok == T_LBRACE || tok == T_LBRACKET) {
1245 				index = nextIndex++;
1246 				goto gotIndex;
1247 			}
1248 
1249 			/* Might be an index, might be a value, either way... */
1250 			if (tok != T_WORD) {
1251 				error = EINVAL;
1252 				goto done;
1253 			}
1254 
1255 			/* If no equals sign follows, index is implied */
1256 			off2 = *off + len;
1257 			if (ng_parse_get_token(s, &off2, &len2) != T_EQUALS) {
1258 				index = nextIndex++;
1259 				goto gotIndex;
1260 			}
1261 
1262 			/* Index was specified explicitly; parse it */
1263 			ul = strtoul(s + *off, &eptr, 0);
1264 			if (ul == ULONG_MAX || eptr - (s + *off) != len) {
1265 				error = EINVAL;
1266 				goto done;
1267 			}
1268 			index = (u_int)ul;
1269 			nextIndex = index + 1;
1270 			*off += len + len2;
1271 		} else {			/* a structure field */
1272 			const struct ng_parse_struct_field *const
1273 			    fields = type->info;
1274 
1275 			/* Find the field by name (required) in field list */
1276 			if (tok != T_WORD) {
1277 				error = EINVAL;
1278 				goto done;
1279 			}
1280 			for (index = 0; index < num; index++) {
1281 				const struct ng_parse_struct_field *const
1282 				    field = &fields[index];
1283 
1284 				if (strncmp(&s[*off], field->name, len) == 0
1285 				    && field->name[len] == '\0')
1286 					break;
1287 			}
1288 			if (index == num) {
1289 				error = ENOENT;
1290 				goto done;
1291 			}
1292 			*off += len;
1293 
1294 			/* Get equals sign */
1295 			if (ng_parse_get_token(s, off, &len) != T_EQUALS) {
1296 				error = EINVAL;
1297 				goto done;
1298 			}
1299 			*off += len;
1300 		}
1301 gotIndex:
1302 
1303 		/* Check array index */
1304 		if (index >= num) {
1305 			error = E2BIG;
1306 			goto done;
1307 		}
1308 
1309 		/* Save value's position and skip over it for now */
1310 		if (foff[index] != 0) {
1311 			error = EALREADY;		/* duplicate */
1312 			goto done;
1313 		}
1314 		while (isspace(s[*off]))
1315 			(*off)++;
1316 		foff[index] = *off;
1317 		if ((error = ng_parse_skip_value(s, *off, &len)) != 0)
1318 			goto done;
1319 		*off += len;
1320 	}
1321 
1322 	/* Now build binary structure from supplied values and defaults */
1323 	for (blen = index = 0; index < num; index++) {
1324 		const struct ng_parse_type *const
1325 		    etype = ng_get_composite_etype(type, index, ctype);
1326 		int k, pad, vlen;
1327 
1328 		/* Zero-pad any alignment bytes */
1329 		pad = ng_parse_get_elem_pad(type, index, ctype, blen);
1330 		for (k = 0; k < pad; k++) {
1331 			if (blen >= *buflen) {
1332 				error = ERANGE;
1333 				goto done;
1334 			}
1335 			buf[blen++] = 0;
1336 		}
1337 
1338 		/* Get value */
1339 		vlen = *buflen - blen;
1340 		if (foff[index] == 0) {		/* use default value */
1341 			error = ng_get_composite_elem_default(type, index,
1342 			    start, buf + blen, &vlen, ctype);
1343 		} else {			/* parse given value */
1344 			*off = foff[index];
1345 			error = INVOKE(etype, parse)(etype,
1346 			    s, off, start, buf + blen, &vlen);
1347 		}
1348 		if (error != 0)
1349 			goto done;
1350 		blen += vlen;
1351 	}
1352 
1353 	/* Make total composite structure size a multiple of its alignment */
1354 	if ((align = ALIGNMENT(type)) != 0) {
1355 		while (blen % align != 0) {
1356 			if (blen >= *buflen) {
1357 				error = ERANGE;
1358 				goto done;
1359 			}
1360 			buf[blen++] = 0;
1361 		}
1362 	}
1363 
1364 	/* Done */
1365 	*buflen = blen;
1366 done:
1367 	if (foff != NULL)
1368 		free(foff, M_NETGRAPH_PARSE);
1369 	return (error);
1370 }
1371 
1372 /*
1373  * Convert an array or structure from binary to ASCII
1374  */
1375 static int
1376 ng_unparse_composite(const struct ng_parse_type *type, const u_char *data,
1377 	int *off, char *cbuf, int cbuflen, const enum comptype ctype)
1378 {
1379 	const struct ng_mesg *const hdr
1380 	    = (const struct ng_mesg *)(data - sizeof(*hdr));
1381 	const int num = ng_get_composite_len(type, data, data + *off, ctype);
1382 	const int workSize = 20 * 1024;		/* XXX hard coded constant */
1383 	int nextIndex = 0, didOne = 0;
1384 	int error, index;
1385 	u_char *workBuf;
1386 
1387 	/* Get workspace for checking default values */
1388 	workBuf = malloc(workSize, M_NETGRAPH_PARSE, M_NOWAIT);
1389 	if (workBuf == NULL)
1390 		return (ENOMEM);
1391 
1392 	/* Opening brace/bracket */
1393 	if ((error = ng_parse_append(&cbuf, &cbuflen, "%c",
1394 	    (ctype == CT_STRUCT) ? '{' : '[')) != 0)
1395 		goto fail;
1396 
1397 	/* Do each item */
1398 	for (index = 0; index < num; index++) {
1399 		const struct ng_parse_type *const
1400 		    etype = ng_get_composite_etype(type, index, ctype);
1401 
1402 		/* Skip any alignment pad bytes */
1403 		*off += ng_parse_get_elem_pad(type, index, ctype, *off);
1404 
1405 		/*
1406 		 * See if element is equal to its default value; skip if so.
1407 		 * Copy struct ng_mesg header for types that peek into it.
1408 		 */
1409 		if (sizeof(*hdr) + *off < workSize) {
1410 			int tempsize = workSize - sizeof(*hdr) - *off;
1411 
1412 			bcopy(hdr, workBuf, sizeof(*hdr) + *off);
1413 			if (ng_get_composite_elem_default(type, index, workBuf
1414 			      + sizeof(*hdr), workBuf + sizeof(*hdr) + *off,
1415 			      &tempsize, ctype) == 0
1416 			    && bcmp(workBuf + sizeof(*hdr) + *off,
1417 			      data + *off, tempsize) == 0) {
1418 				*off += tempsize;
1419 				continue;
1420 			}
1421 		}
1422 
1423 		/* Print name= */
1424 		if ((error = ng_parse_append(&cbuf, &cbuflen, " ")) != 0)
1425 			goto fail;
1426 		if (ctype != CT_STRUCT) {
1427 			if (index != nextIndex) {
1428 				nextIndex = index;
1429 				if ((error = ng_parse_append(&cbuf,
1430 				    &cbuflen, "%d=", index)) != 0)
1431 					goto fail;
1432 			}
1433 			nextIndex++;
1434 		} else {
1435 			const struct ng_parse_struct_field *const
1436 			    fields = type->info;
1437 
1438 			if ((error = ng_parse_append(&cbuf,
1439 			    &cbuflen, "%s=", fields[index].name)) != 0)
1440 				goto fail;
1441 		}
1442 
1443 		/* Print value */
1444 		if ((error = INVOKE(etype, unparse)
1445 		    (etype, data, off, cbuf, cbuflen)) != 0) {
1446 			free(workBuf, M_NETGRAPH_PARSE);
1447 			return (error);
1448 		}
1449 		cbuflen -= strlen(cbuf);
1450 		cbuf += strlen(cbuf);
1451 		didOne = 1;
1452 	}
1453 
1454 	/* Closing brace/bracket */
1455 	error = ng_parse_append(&cbuf, &cbuflen, "%s%c",
1456 	    didOne ? " " : "", (ctype == CT_STRUCT) ? '}' : ']');
1457 
1458 fail:
1459 	/* Clean up after failure */
1460 	free(workBuf, M_NETGRAPH_PARSE);
1461 	return (error);
1462 }
1463 
1464 /*
1465  * Generate the default value for an element of an array or structure
1466  * Returns EOPNOTSUPP if default value is unspecified.
1467  */
1468 static int
1469 ng_get_composite_elem_default(const struct ng_parse_type *type,
1470 	int index, const u_char *const start, u_char *buf, int *buflen,
1471 	const enum comptype ctype)
1472 {
1473 	const struct ng_parse_type *etype;
1474 	ng_getDefault_t *func;
1475 
1476 	switch (ctype) {
1477 	case CT_STRUCT:
1478 		break;
1479 	case CT_ARRAY:
1480 	    {
1481 		const struct ng_parse_array_info *const ai = type->info;
1482 
1483 		if (ai->getDefault != NULL) {
1484 			return (*ai->getDefault)(type,
1485 			    index, start, buf, buflen);
1486 		}
1487 		break;
1488 	    }
1489 	case CT_FIXEDARRAY:
1490 	    {
1491 		const struct ng_parse_fixedarray_info *const fi = type->info;
1492 
1493 		if (*fi->getDefault != NULL) {
1494 			return (*fi->getDefault)(type,
1495 			    index, start, buf, buflen);
1496 		}
1497 		break;
1498 	    }
1499 	default:
1500 	    panic("%s", __func__);
1501 	}
1502 
1503 	/* Default to element type default */
1504 	etype = ng_get_composite_etype(type, index, ctype);
1505 	func = METHOD(etype, getDefault);
1506 	if (func == NULL)
1507 		return (EOPNOTSUPP);
1508 	return (*func)(etype, start, buf, buflen);
1509 }
1510 
1511 /*
1512  * Get the number of elements in a struct, variable or fixed array.
1513  */
1514 static int
1515 ng_get_composite_len(const struct ng_parse_type *type,
1516 	const u_char *const start, const u_char *buf,
1517 	const enum comptype ctype)
1518 {
1519 	switch (ctype) {
1520 	case CT_STRUCT:
1521 	    {
1522 		const struct ng_parse_struct_field *const fields = type->info;
1523 		int numFields = 0;
1524 
1525 		for (numFields = 0; ; numFields++) {
1526 			const struct ng_parse_struct_field *const
1527 				fi = &fields[numFields];
1528 
1529 			if (fi->name == NULL)
1530 				break;
1531 		}
1532 		return (numFields);
1533 	    }
1534 	case CT_ARRAY:
1535 	    {
1536 		const struct ng_parse_array_info *const ai = type->info;
1537 
1538 		return (*ai->getLength)(type, start, buf);
1539 	    }
1540 	case CT_FIXEDARRAY:
1541 	    {
1542 		const struct ng_parse_fixedarray_info *const fi = type->info;
1543 
1544 		return fi->length;
1545 	    }
1546 	default:
1547 	    panic("%s", __func__);
1548 	}
1549 	return (0);
1550 }
1551 
1552 /*
1553  * Return the type of the index'th element of a composite structure
1554  */
1555 static const struct ng_parse_type *
1556 ng_get_composite_etype(const struct ng_parse_type *type,
1557 	int index, const enum comptype ctype)
1558 {
1559 	const struct ng_parse_type *etype = NULL;
1560 
1561 	switch (ctype) {
1562 	case CT_STRUCT:
1563 	    {
1564 		const struct ng_parse_struct_field *const fields = type->info;
1565 
1566 		etype = fields[index].type;
1567 		break;
1568 	    }
1569 	case CT_ARRAY:
1570 	    {
1571 		const struct ng_parse_array_info *const ai = type->info;
1572 
1573 		etype = ai->elementType;
1574 		break;
1575 	    }
1576 	case CT_FIXEDARRAY:
1577 	    {
1578 		const struct ng_parse_fixedarray_info *const fi = type->info;
1579 
1580 		etype = fi->elementType;
1581 		break;
1582 	    }
1583 	default:
1584 	    panic("%s", __func__);
1585 	}
1586 	return (etype);
1587 }
1588 
1589 /*
1590  * Get the number of bytes to skip to align for the next
1591  * element in a composite structure.
1592  */
1593 static int
1594 ng_parse_get_elem_pad(const struct ng_parse_type *type,
1595 	int index, enum comptype ctype, int posn)
1596 {
1597 	const struct ng_parse_type *const
1598 	    etype = ng_get_composite_etype(type, index, ctype);
1599 	int align;
1600 
1601 	/* Get element's alignment, and possibly override */
1602 	align = ALIGNMENT(etype);
1603 	if (ctype == CT_STRUCT) {
1604 		const struct ng_parse_struct_field *const fields = type->info;
1605 
1606 		if (fields[index].alignment != 0)
1607 			align = fields[index].alignment;
1608 	}
1609 
1610 	/* Return number of bytes to skip to align */
1611 	return (align ? (align - (posn % align)) % align : 0);
1612 }
1613 
1614 /************************************************************************
1615 			PARSING HELPER ROUTINES
1616  ************************************************************************/
1617 
1618 /*
1619  * Append to a fixed length string buffer.
1620  */
1621 static int
1622 ng_parse_append(char **cbufp, int *cbuflenp, const char *fmt, ...)
1623 {
1624 	va_list args;
1625 	int len;
1626 
1627 	va_start(args, fmt);
1628 	len = vsnprintf(*cbufp, *cbuflenp, fmt, args);
1629 	va_end(args);
1630 	if (len >= *cbuflenp)
1631 		return ERANGE;
1632 	*cbufp += len;
1633 	*cbuflenp -= len;
1634 
1635 	return (0);
1636 }
1637 
1638 /*
1639  * Skip over a value
1640  */
1641 static int
1642 ng_parse_skip_value(const char *s, int off0, int *lenp)
1643 {
1644 	int len, nbracket, nbrace;
1645 	int off = off0;
1646 
1647 	len = nbracket = nbrace = 0;
1648 	do {
1649 		switch (ng_parse_get_token(s, &off, &len)) {
1650 		case T_LBRACKET:
1651 			nbracket++;
1652 			break;
1653 		case T_LBRACE:
1654 			nbrace++;
1655 			break;
1656 		case T_RBRACKET:
1657 			if (nbracket-- == 0)
1658 				return (EINVAL);
1659 			break;
1660 		case T_RBRACE:
1661 			if (nbrace-- == 0)
1662 				return (EINVAL);
1663 			break;
1664 		case T_EOF:
1665 			return (EINVAL);
1666 		default:
1667 			break;
1668 		}
1669 		off += len;
1670 	} while (nbracket > 0 || nbrace > 0);
1671 	*lenp = off - off0;
1672 	return (0);
1673 }
1674 
1675 /*
1676  * Find the next token in the string, starting at offset *startp.
1677  * Returns the token type, with *startp pointing to the first char
1678  * and *lenp the length.
1679  */
1680 enum ng_parse_token
1681 ng_parse_get_token(const char *s, int *startp, int *lenp)
1682 {
1683 	char *t;
1684 	int i;
1685 
1686 	while (isspace(s[*startp]))
1687 		(*startp)++;
1688 	switch (s[*startp]) {
1689 	case '\0':
1690 		*lenp = 0;
1691 		return T_EOF;
1692 	case '{':
1693 		*lenp = 1;
1694 		return T_LBRACE;
1695 	case '}':
1696 		*lenp = 1;
1697 		return T_RBRACE;
1698 	case '[':
1699 		*lenp = 1;
1700 		return T_LBRACKET;
1701 	case ']':
1702 		*lenp = 1;
1703 		return T_RBRACKET;
1704 	case '=':
1705 		*lenp = 1;
1706 		return T_EQUALS;
1707 	case '"':
1708 		if ((t = ng_get_string_token(s, startp, lenp, NULL)) == NULL)
1709 			return T_ERROR;
1710 		free(t, M_NETGRAPH_PARSE);
1711 		return T_STRING;
1712 	default:
1713 		for (i = *startp + 1; s[i] != '\0' && !isspace(s[i])
1714 		    && s[i] != '{' && s[i] != '}' && s[i] != '['
1715 		    && s[i] != ']' && s[i] != '=' && s[i] != '"'; i++)
1716 			;
1717 		*lenp = i - *startp;
1718 		return T_WORD;
1719 	}
1720 }
1721 
1722 /*
1723  * Get a string token, which must be enclosed in double quotes.
1724  * The normal C backslash escapes are recognized.
1725  */
1726 char *
1727 ng_get_string_token(const char *s, int *startp, int *lenp, int *slenp)
1728 {
1729 	char *cbuf, *p;
1730 	int start, off;
1731 	int slen;
1732 
1733 	while (isspace(s[*startp]))
1734 		(*startp)++;
1735 	start = *startp;
1736 	if (s[*startp] != '"')
1737 		return (NULL);
1738 	cbuf = malloc(strlen(s + start), M_NETGRAPH_PARSE, M_NOWAIT);
1739 	if (cbuf == NULL)
1740 		return (NULL);
1741 	strcpy(cbuf, s + start + 1);
1742 	for (slen = 0, off = 1, p = cbuf; *p != '\0'; slen++, off++, p++) {
1743 		if (*p == '"') {
1744 			*p = '\0';
1745 			*lenp = off + 1;
1746 			if (slenp != NULL)
1747 				*slenp = slen;
1748 			return (cbuf);
1749 		} else if (p[0] == '\\' && p[1] != '\0') {
1750 			int x, k;
1751 			char *v;
1752 
1753 			strcpy(p, p + 1);
1754 			v = p;
1755 			switch (*p) {
1756 			case 't':
1757 				*v = '\t';
1758 				off++;
1759 				continue;
1760 			case 'n':
1761 				*v = '\n';
1762 				off++;
1763 				continue;
1764 			case 'r':
1765 				*v = '\r';
1766 				off++;
1767 				continue;
1768 			case 'v':
1769 				*v =  '\v';
1770 				off++;
1771 				continue;
1772 			case 'f':
1773 				*v =  '\f';
1774 				off++;
1775 				continue;
1776 			case '"':
1777 				*v =  '"';
1778 				off++;
1779 				continue;
1780 			case '0': case '1': case '2': case '3':
1781 			case '4': case '5': case '6': case '7':
1782 				for (x = k = 0;
1783 				    k < 3 && *v >= '0' && *v <= '7'; v++) {
1784 					x = (x << 3) + (*v - '0');
1785 					off++;
1786 				}
1787 				*--v = (char)x;
1788 				break;
1789 			case 'x':
1790 				for (v++, x = k = 0;
1791 				    k < 2 && isxdigit(*v); v++) {
1792 					x = (x << 4) + (isdigit(*v) ?
1793 					      (*v - '0') :
1794 					      (tolower(*v) - 'a' + 10));
1795 					off++;
1796 				}
1797 				*--v = (char)x;
1798 				break;
1799 			default:
1800 				continue;
1801 			}
1802 			strcpy(p, v);
1803 		}
1804 	}
1805 	free(cbuf, M_NETGRAPH_PARSE);
1806 	return (NULL);		/* no closing quote */
1807 }
1808 
1809 /*
1810  * Encode a string so it can be safely put in double quotes.
1811  * Caller must free the result. Exactly "slen" characters
1812  * are encoded.
1813  */
1814 char *
1815 ng_encode_string(const char *raw, int slen)
1816 {
1817 	char *cbuf;
1818 	int off = 0;
1819 	int i;
1820 
1821 	cbuf = malloc(strlen(raw) * 4 + 3, M_NETGRAPH_PARSE, M_NOWAIT);
1822 	if (cbuf == NULL)
1823 		return (NULL);
1824 	cbuf[off++] = '"';
1825 	for (i = 0; i < slen; i++, raw++) {
1826 		switch (*raw) {
1827 		case '\t':
1828 			cbuf[off++] = '\\';
1829 			cbuf[off++] = 't';
1830 			break;
1831 		case '\f':
1832 			cbuf[off++] = '\\';
1833 			cbuf[off++] = 'f';
1834 			break;
1835 		case '\n':
1836 			cbuf[off++] = '\\';
1837 			cbuf[off++] = 'n';
1838 			break;
1839 		case '\r':
1840 			cbuf[off++] = '\\';
1841 			cbuf[off++] = 'r';
1842 			break;
1843 		case '\v':
1844 			cbuf[off++] = '\\';
1845 			cbuf[off++] = 'v';
1846 			break;
1847 		case '"':
1848 		case '\\':
1849 			cbuf[off++] = '\\';
1850 			cbuf[off++] = *raw;
1851 			break;
1852 		default:
1853 			if (*raw < 0x20 || *raw > 0x7e) {
1854 				off += sprintf(cbuf + off,
1855 				    "\\x%02x", (u_char)*raw);
1856 				break;
1857 			}
1858 			cbuf[off++] = *raw;
1859 			break;
1860 		}
1861 	}
1862 	cbuf[off++] = '"';
1863 	cbuf[off] = '\0';
1864 	return (cbuf);
1865 }
1866 
1867 /************************************************************************
1868 			VIRTUAL METHOD LOOKUP
1869  ************************************************************************/
1870 
1871 static ng_parse_t *
1872 ng_get_parse_method(const struct ng_parse_type *t)
1873 {
1874 	while (t != NULL && t->parse == NULL)
1875 		t = t->supertype;
1876 	return (t ? t->parse : NULL);
1877 }
1878 
1879 static ng_unparse_t *
1880 ng_get_unparse_method(const struct ng_parse_type *t)
1881 {
1882 	while (t != NULL && t->unparse == NULL)
1883 		t = t->supertype;
1884 	return (t ? t->unparse : NULL);
1885 }
1886 
1887 static ng_getDefault_t *
1888 ng_get_getDefault_method(const struct ng_parse_type *t)
1889 {
1890 	while (t != NULL && t->getDefault == NULL)
1891 		t = t->supertype;
1892 	return (t ? t->getDefault : NULL);
1893 }
1894 
1895 static ng_getAlign_t *
1896 ng_get_getAlign_method(const struct ng_parse_type *t)
1897 {
1898 	while (t != NULL && t->getAlign == NULL)
1899 		t = t->supertype;
1900 	return (t ? t->getAlign : NULL);
1901 }
1902 
1903