xref: /freebsd/sys/netgraph/ng_parse.c (revision 586f63035fbe5e45cfc971037fd76375661ece26)
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 			int len2, off2;
1240 			char *eptr;
1241 
1242 			/* If an opening brace/bracket, index is implied */
1243 			if (tok == T_LBRACE || tok == T_LBRACKET) {
1244 				index = nextIndex++;
1245 				goto gotIndex;
1246 			}
1247 
1248 			/* Might be an index, might be a value, either way... */
1249 			if (tok != T_WORD) {
1250 				error = EINVAL;
1251 				goto done;
1252 			}
1253 
1254 			/* If no equals sign follows, index is implied */
1255 			off2 = *off + len;
1256 			if (ng_parse_get_token(s, &off2, &len2) != T_EQUALS) {
1257 				index = nextIndex++;
1258 				goto gotIndex;
1259 			}
1260 
1261 			/* Index was specified explicitly; parse it */
1262 			index = (u_int)strtoul(s + *off, &eptr, 0);
1263 			if (index < 0 || eptr - (s + *off) != len) {
1264 				error = EINVAL;
1265 				goto done;
1266 			}
1267 			nextIndex = index + 1;
1268 			*off += len + len2;
1269 		} else {			/* a structure field */
1270 			const struct ng_parse_struct_field *const
1271 			    fields = type->info;
1272 
1273 			/* Find the field by name (required) in field list */
1274 			if (tok != T_WORD) {
1275 				error = EINVAL;
1276 				goto done;
1277 			}
1278 			for (index = 0; index < num; index++) {
1279 				const struct ng_parse_struct_field *const
1280 				    field = &fields[index];
1281 
1282 				if (strncmp(&s[*off], field->name, len) == 0
1283 				    && field->name[len] == '\0')
1284 					break;
1285 			}
1286 			if (index == num) {
1287 				error = ENOENT;
1288 				goto done;
1289 			}
1290 			*off += len;
1291 
1292 			/* Get equals sign */
1293 			if (ng_parse_get_token(s, off, &len) != T_EQUALS) {
1294 				error = EINVAL;
1295 				goto done;
1296 			}
1297 			*off += len;
1298 		}
1299 gotIndex:
1300 
1301 		/* Check array index */
1302 		if (index >= num) {
1303 			error = E2BIG;
1304 			goto done;
1305 		}
1306 
1307 		/* Save value's position and skip over it for now */
1308 		if (foff[index] != 0) {
1309 			error = EALREADY;		/* duplicate */
1310 			goto done;
1311 		}
1312 		while (isspace(s[*off]))
1313 			(*off)++;
1314 		foff[index] = *off;
1315 		if ((error = ng_parse_skip_value(s, *off, &len)) != 0)
1316 			goto done;
1317 		*off += len;
1318 	}
1319 
1320 	/* Now build binary structure from supplied values and defaults */
1321 	for (blen = index = 0; index < num; index++) {
1322 		const struct ng_parse_type *const
1323 		    etype = ng_get_composite_etype(type, index, ctype);
1324 		int k, pad, vlen;
1325 
1326 		/* Zero-pad any alignment bytes */
1327 		pad = ng_parse_get_elem_pad(type, index, ctype, blen);
1328 		for (k = 0; k < pad; k++) {
1329 			if (blen >= *buflen) {
1330 				error = ERANGE;
1331 				goto done;
1332 			}
1333 			buf[blen++] = 0;
1334 		}
1335 
1336 		/* Get value */
1337 		vlen = *buflen - blen;
1338 		if (foff[index] == 0) {		/* use default value */
1339 			error = ng_get_composite_elem_default(type, index,
1340 			    start, buf + blen, &vlen, ctype);
1341 		} else {			/* parse given value */
1342 			*off = foff[index];
1343 			error = INVOKE(etype, parse)(etype,
1344 			    s, off, start, buf + blen, &vlen);
1345 		}
1346 		if (error != 0)
1347 			goto done;
1348 		blen += vlen;
1349 	}
1350 
1351 	/* Make total composite structure size a multiple of its alignment */
1352 	if ((align = ALIGNMENT(type)) != 0) {
1353 		while (blen % align != 0) {
1354 			if (blen >= *buflen) {
1355 				error = ERANGE;
1356 				goto done;
1357 			}
1358 			buf[blen++] = 0;
1359 		}
1360 	}
1361 
1362 	/* Done */
1363 	*buflen = blen;
1364 done:
1365 	if (foff != NULL)
1366 		free(foff, M_NETGRAPH_PARSE);
1367 	return (error);
1368 }
1369 
1370 /*
1371  * Convert an array or structure from binary to ASCII
1372  */
1373 static int
1374 ng_unparse_composite(const struct ng_parse_type *type, const u_char *data,
1375 	int *off, char *cbuf, int cbuflen, const enum comptype ctype)
1376 {
1377 	const struct ng_mesg *const hdr
1378 	    = (const struct ng_mesg *)(data - sizeof(*hdr));
1379 	const int num = ng_get_composite_len(type, data, data + *off, ctype);
1380 	const int workSize = 20 * 1024;		/* XXX hard coded constant */
1381 	int nextIndex = 0, didOne = 0;
1382 	int error, index;
1383 	u_char *workBuf;
1384 
1385 	/* Get workspace for checking default values */
1386 	workBuf = malloc(workSize, M_NETGRAPH_PARSE, M_NOWAIT);
1387 	if (workBuf == NULL)
1388 		return (ENOMEM);
1389 
1390 	/* Opening brace/bracket */
1391 	if ((error = ng_parse_append(&cbuf, &cbuflen, "%c",
1392 	    (ctype == CT_STRUCT) ? '{' : '[')) != 0)
1393 		goto fail;
1394 
1395 	/* Do each item */
1396 	for (index = 0; index < num; index++) {
1397 		const struct ng_parse_type *const
1398 		    etype = ng_get_composite_etype(type, index, ctype);
1399 
1400 		/* Skip any alignment pad bytes */
1401 		*off += ng_parse_get_elem_pad(type, index, ctype, *off);
1402 
1403 		/*
1404 		 * See if element is equal to its default value; skip if so.
1405 		 * Copy struct ng_mesg header for types that peek into it.
1406 		 */
1407 		if (sizeof(*hdr) + *off < workSize) {
1408 			int tempsize = workSize - sizeof(*hdr) - *off;
1409 
1410 			bcopy(hdr, workBuf, sizeof(*hdr) + *off);
1411 			if (ng_get_composite_elem_default(type, index, workBuf
1412 			      + sizeof(*hdr), workBuf + sizeof(*hdr) + *off,
1413 			      &tempsize, ctype) == 0
1414 			    && bcmp(workBuf + sizeof(*hdr) + *off,
1415 			      data + *off, tempsize) == 0) {
1416 				*off += tempsize;
1417 				continue;
1418 			}
1419 		}
1420 
1421 		/* Print name= */
1422 		if ((error = ng_parse_append(&cbuf, &cbuflen, " ")) != 0)
1423 			goto fail;
1424 		if (ctype != CT_STRUCT) {
1425 			if (index != nextIndex) {
1426 				nextIndex = index;
1427 				if ((error = ng_parse_append(&cbuf,
1428 				    &cbuflen, "%d=", index)) != 0)
1429 					goto fail;
1430 			}
1431 			nextIndex++;
1432 		} else {
1433 			const struct ng_parse_struct_field *const
1434 			    fields = type->info;
1435 
1436 			if ((error = ng_parse_append(&cbuf,
1437 			    &cbuflen, "%s=", fields[index].name)) != 0)
1438 				goto fail;
1439 		}
1440 
1441 		/* Print value */
1442 		if ((error = INVOKE(etype, unparse)
1443 		    (etype, data, off, cbuf, cbuflen)) != 0) {
1444 			free(workBuf, M_NETGRAPH_PARSE);
1445 			return (error);
1446 		}
1447 		cbuflen -= strlen(cbuf);
1448 		cbuf += strlen(cbuf);
1449 		didOne = 1;
1450 	}
1451 
1452 	/* Closing brace/bracket */
1453 	error = ng_parse_append(&cbuf, &cbuflen, "%s%c",
1454 	    didOne ? " " : "", (ctype == CT_STRUCT) ? '}' : ']');
1455 
1456 fail:
1457 	/* Clean up after failure */
1458 	free(workBuf, M_NETGRAPH_PARSE);
1459 	return (error);
1460 }
1461 
1462 /*
1463  * Generate the default value for an element of an array or structure
1464  * Returns EOPNOTSUPP if default value is unspecified.
1465  */
1466 static int
1467 ng_get_composite_elem_default(const struct ng_parse_type *type,
1468 	int index, const u_char *const start, u_char *buf, int *buflen,
1469 	const enum comptype ctype)
1470 {
1471 	const struct ng_parse_type *etype;
1472 	ng_getDefault_t *func;
1473 
1474 	switch (ctype) {
1475 	case CT_STRUCT:
1476 		break;
1477 	case CT_ARRAY:
1478 	    {
1479 		const struct ng_parse_array_info *const ai = type->info;
1480 
1481 		if (ai->getDefault != NULL) {
1482 			return (*ai->getDefault)(type,
1483 			    index, start, buf, buflen);
1484 		}
1485 		break;
1486 	    }
1487 	case CT_FIXEDARRAY:
1488 	    {
1489 		const struct ng_parse_fixedarray_info *const fi = type->info;
1490 
1491 		if (*fi->getDefault != NULL) {
1492 			return (*fi->getDefault)(type,
1493 			    index, start, buf, buflen);
1494 		}
1495 		break;
1496 	    }
1497 	default:
1498 	    panic("%s", __func__);
1499 	}
1500 
1501 	/* Default to element type default */
1502 	etype = ng_get_composite_etype(type, index, ctype);
1503 	func = METHOD(etype, getDefault);
1504 	if (func == NULL)
1505 		return (EOPNOTSUPP);
1506 	return (*func)(etype, start, buf, buflen);
1507 }
1508 
1509 /*
1510  * Get the number of elements in a struct, variable or fixed array.
1511  */
1512 static int
1513 ng_get_composite_len(const struct ng_parse_type *type,
1514 	const u_char *const start, const u_char *buf,
1515 	const enum comptype ctype)
1516 {
1517 	switch (ctype) {
1518 	case CT_STRUCT:
1519 	    {
1520 		const struct ng_parse_struct_field *const fields = type->info;
1521 		int numFields = 0;
1522 
1523 		for (numFields = 0; ; numFields++) {
1524 			const struct ng_parse_struct_field *const
1525 				fi = &fields[numFields];
1526 
1527 			if (fi->name == NULL)
1528 				break;
1529 		}
1530 		return (numFields);
1531 	    }
1532 	case CT_ARRAY:
1533 	    {
1534 		const struct ng_parse_array_info *const ai = type->info;
1535 
1536 		return (*ai->getLength)(type, start, buf);
1537 	    }
1538 	case CT_FIXEDARRAY:
1539 	    {
1540 		const struct ng_parse_fixedarray_info *const fi = type->info;
1541 
1542 		return fi->length;
1543 	    }
1544 	default:
1545 	    panic("%s", __func__);
1546 	}
1547 	return (0);
1548 }
1549 
1550 /*
1551  * Return the type of the index'th element of a composite structure
1552  */
1553 static const struct ng_parse_type *
1554 ng_get_composite_etype(const struct ng_parse_type *type,
1555 	int index, const enum comptype ctype)
1556 {
1557 	const struct ng_parse_type *etype = NULL;
1558 
1559 	switch (ctype) {
1560 	case CT_STRUCT:
1561 	    {
1562 		const struct ng_parse_struct_field *const fields = type->info;
1563 
1564 		etype = fields[index].type;
1565 		break;
1566 	    }
1567 	case CT_ARRAY:
1568 	    {
1569 		const struct ng_parse_array_info *const ai = type->info;
1570 
1571 		etype = ai->elementType;
1572 		break;
1573 	    }
1574 	case CT_FIXEDARRAY:
1575 	    {
1576 		const struct ng_parse_fixedarray_info *const fi = type->info;
1577 
1578 		etype = fi->elementType;
1579 		break;
1580 	    }
1581 	default:
1582 	    panic("%s", __func__);
1583 	}
1584 	return (etype);
1585 }
1586 
1587 /*
1588  * Get the number of bytes to skip to align for the next
1589  * element in a composite structure.
1590  */
1591 static int
1592 ng_parse_get_elem_pad(const struct ng_parse_type *type,
1593 	int index, enum comptype ctype, int posn)
1594 {
1595 	const struct ng_parse_type *const
1596 	    etype = ng_get_composite_etype(type, index, ctype);
1597 	int align;
1598 
1599 	/* Get element's alignment, and possibly override */
1600 	align = ALIGNMENT(etype);
1601 	if (ctype == CT_STRUCT) {
1602 		const struct ng_parse_struct_field *const fields = type->info;
1603 
1604 		if (fields[index].alignment != 0)
1605 			align = fields[index].alignment;
1606 	}
1607 
1608 	/* Return number of bytes to skip to align */
1609 	return (align ? (align - (posn % align)) % align : 0);
1610 }
1611 
1612 /************************************************************************
1613 			PARSING HELPER ROUTINES
1614  ************************************************************************/
1615 
1616 /*
1617  * Append to a fixed length string buffer.
1618  */
1619 static int
1620 ng_parse_append(char **cbufp, int *cbuflenp, const char *fmt, ...)
1621 {
1622 	va_list args;
1623 	int len;
1624 
1625 	va_start(args, fmt);
1626 	len = vsnprintf(*cbufp, *cbuflenp, fmt, args);
1627 	va_end(args);
1628 	if (len >= *cbuflenp)
1629 		return ERANGE;
1630 	*cbufp += len;
1631 	*cbuflenp -= len;
1632 
1633 	return (0);
1634 }
1635 
1636 /*
1637  * Skip over a value
1638  */
1639 static int
1640 ng_parse_skip_value(const char *s, int off0, int *lenp)
1641 {
1642 	int len, nbracket, nbrace;
1643 	int off = off0;
1644 
1645 	len = nbracket = nbrace = 0;
1646 	do {
1647 		switch (ng_parse_get_token(s, &off, &len)) {
1648 		case T_LBRACKET:
1649 			nbracket++;
1650 			break;
1651 		case T_LBRACE:
1652 			nbrace++;
1653 			break;
1654 		case T_RBRACKET:
1655 			if (nbracket-- == 0)
1656 				return (EINVAL);
1657 			break;
1658 		case T_RBRACE:
1659 			if (nbrace-- == 0)
1660 				return (EINVAL);
1661 			break;
1662 		case T_EOF:
1663 			return (EINVAL);
1664 		default:
1665 			break;
1666 		}
1667 		off += len;
1668 	} while (nbracket > 0 || nbrace > 0);
1669 	*lenp = off - off0;
1670 	return (0);
1671 }
1672 
1673 /*
1674  * Find the next token in the string, starting at offset *startp.
1675  * Returns the token type, with *startp pointing to the first char
1676  * and *lenp the length.
1677  */
1678 enum ng_parse_token
1679 ng_parse_get_token(const char *s, int *startp, int *lenp)
1680 {
1681 	char *t;
1682 	int i;
1683 
1684 	while (isspace(s[*startp]))
1685 		(*startp)++;
1686 	switch (s[*startp]) {
1687 	case '\0':
1688 		*lenp = 0;
1689 		return T_EOF;
1690 	case '{':
1691 		*lenp = 1;
1692 		return T_LBRACE;
1693 	case '}':
1694 		*lenp = 1;
1695 		return T_RBRACE;
1696 	case '[':
1697 		*lenp = 1;
1698 		return T_LBRACKET;
1699 	case ']':
1700 		*lenp = 1;
1701 		return T_RBRACKET;
1702 	case '=':
1703 		*lenp = 1;
1704 		return T_EQUALS;
1705 	case '"':
1706 		if ((t = ng_get_string_token(s, startp, lenp, NULL)) == NULL)
1707 			return T_ERROR;
1708 		free(t, M_NETGRAPH_PARSE);
1709 		return T_STRING;
1710 	default:
1711 		for (i = *startp + 1; s[i] != '\0' && !isspace(s[i])
1712 		    && s[i] != '{' && s[i] != '}' && s[i] != '['
1713 		    && s[i] != ']' && s[i] != '=' && s[i] != '"'; i++)
1714 			;
1715 		*lenp = i - *startp;
1716 		return T_WORD;
1717 	}
1718 }
1719 
1720 /*
1721  * Get a string token, which must be enclosed in double quotes.
1722  * The normal C backslash escapes are recognized.
1723  */
1724 char *
1725 ng_get_string_token(const char *s, int *startp, int *lenp, int *slenp)
1726 {
1727 	char *cbuf, *p;
1728 	int start, off;
1729 	int slen;
1730 
1731 	while (isspace(s[*startp]))
1732 		(*startp)++;
1733 	start = *startp;
1734 	if (s[*startp] != '"')
1735 		return (NULL);
1736 	cbuf = malloc(strlen(s + start), M_NETGRAPH_PARSE, M_NOWAIT);
1737 	if (cbuf == NULL)
1738 		return (NULL);
1739 	strcpy(cbuf, s + start + 1);
1740 	for (slen = 0, off = 1, p = cbuf; *p != '\0'; slen++, off++, p++) {
1741 		if (*p == '"') {
1742 			*p = '\0';
1743 			*lenp = off + 1;
1744 			if (slenp != NULL)
1745 				*slenp = slen;
1746 			return (cbuf);
1747 		} else if (p[0] == '\\' && p[1] != '\0') {
1748 			int x, k;
1749 			char *v;
1750 
1751 			strcpy(p, p + 1);
1752 			v = p;
1753 			switch (*p) {
1754 			case 't':
1755 				*v = '\t';
1756 				off++;
1757 				continue;
1758 			case 'n':
1759 				*v = '\n';
1760 				off++;
1761 				continue;
1762 			case 'r':
1763 				*v = '\r';
1764 				off++;
1765 				continue;
1766 			case 'v':
1767 				*v =  '\v';
1768 				off++;
1769 				continue;
1770 			case 'f':
1771 				*v =  '\f';
1772 				off++;
1773 				continue;
1774 			case '"':
1775 				*v =  '"';
1776 				off++;
1777 				continue;
1778 			case '0': case '1': case '2': case '3':
1779 			case '4': case '5': case '6': case '7':
1780 				for (x = k = 0;
1781 				    k < 3 && *v >= '0' && *v <= '7'; v++) {
1782 					x = (x << 3) + (*v - '0');
1783 					off++;
1784 				}
1785 				*--v = (char)x;
1786 				break;
1787 			case 'x':
1788 				for (v++, x = k = 0;
1789 				    k < 2 && isxdigit(*v); v++) {
1790 					x = (x << 4) + (isdigit(*v) ?
1791 					      (*v - '0') :
1792 					      (tolower(*v) - 'a' + 10));
1793 					off++;
1794 				}
1795 				*--v = (char)x;
1796 				break;
1797 			default:
1798 				continue;
1799 			}
1800 			strcpy(p, v);
1801 		}
1802 	}
1803 	free(cbuf, M_NETGRAPH_PARSE);
1804 	return (NULL);		/* no closing quote */
1805 }
1806 
1807 /*
1808  * Encode a string so it can be safely put in double quotes.
1809  * Caller must free the result. Exactly "slen" characters
1810  * are encoded.
1811  */
1812 char *
1813 ng_encode_string(const char *raw, int slen)
1814 {
1815 	char *cbuf;
1816 	int off = 0;
1817 	int i;
1818 
1819 	cbuf = malloc(strlen(raw) * 4 + 3, M_NETGRAPH_PARSE, M_NOWAIT);
1820 	if (cbuf == NULL)
1821 		return (NULL);
1822 	cbuf[off++] = '"';
1823 	for (i = 0; i < slen; i++, raw++) {
1824 		switch (*raw) {
1825 		case '\t':
1826 			cbuf[off++] = '\\';
1827 			cbuf[off++] = 't';
1828 			break;
1829 		case '\f':
1830 			cbuf[off++] = '\\';
1831 			cbuf[off++] = 'f';
1832 			break;
1833 		case '\n':
1834 			cbuf[off++] = '\\';
1835 			cbuf[off++] = 'n';
1836 			break;
1837 		case '\r':
1838 			cbuf[off++] = '\\';
1839 			cbuf[off++] = 'r';
1840 			break;
1841 		case '\v':
1842 			cbuf[off++] = '\\';
1843 			cbuf[off++] = 'v';
1844 			break;
1845 		case '"':
1846 		case '\\':
1847 			cbuf[off++] = '\\';
1848 			cbuf[off++] = *raw;
1849 			break;
1850 		default:
1851 			if (*raw < 0x20 || *raw > 0x7e) {
1852 				off += sprintf(cbuf + off,
1853 				    "\\x%02x", (u_char)*raw);
1854 				break;
1855 			}
1856 			cbuf[off++] = *raw;
1857 			break;
1858 		}
1859 	}
1860 	cbuf[off++] = '"';
1861 	cbuf[off] = '\0';
1862 	return (cbuf);
1863 }
1864 
1865 /************************************************************************
1866 			VIRTUAL METHOD LOOKUP
1867  ************************************************************************/
1868 
1869 static ng_parse_t *
1870 ng_get_parse_method(const struct ng_parse_type *t)
1871 {
1872 	while (t != NULL && t->parse == NULL)
1873 		t = t->supertype;
1874 	return (t ? t->parse : NULL);
1875 }
1876 
1877 static ng_unparse_t *
1878 ng_get_unparse_method(const struct ng_parse_type *t)
1879 {
1880 	while (t != NULL && t->unparse == NULL)
1881 		t = t->supertype;
1882 	return (t ? t->unparse : NULL);
1883 }
1884 
1885 static ng_getDefault_t *
1886 ng_get_getDefault_method(const struct ng_parse_type *t)
1887 {
1888 	while (t != NULL && t->getDefault == NULL)
1889 		t = t->supertype;
1890 	return (t ? t->getDefault : NULL);
1891 }
1892 
1893 static ng_getAlign_t *
1894 ng_get_getAlign_method(const struct ng_parse_type *t)
1895 {
1896 	while (t != NULL && t->getAlign == NULL)
1897 		t = t->supertype;
1898 	return (t ? t->getAlign : NULL);
1899 }
1900 
1901