xref: /dragonfly/sys/netgraph/netgraph/ng_parse.c (revision dca3c15d)
1 
2 /*
3  * ng_parse.c
4  *
5  * Copyright (c) 1999 Whistle Communications, Inc.
6  * All rights reserved.
7  *
8  * Subject to the following obligations and disclaimer of warranty, use and
9  * redistribution of this software, in source or object code forms, with or
10  * without modifications are expressly permitted by Whistle Communications;
11  * provided, however, that:
12  * 1. Any and all reproductions of the source or object code must include the
13  *    copyright notice above and the following disclaimer of warranties; and
14  * 2. No rights are granted, in any manner or form, to use Whistle
15  *    Communications, Inc. trademarks, including the mark "WHISTLE
16  *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
17  *    such appears in the above copyright notice or in the software.
18  *
19  * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
20  * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
21  * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
22  * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
23  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
24  * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
25  * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
26  * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
27  * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
28  * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
29  * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
30  * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
31  * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
32  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34  * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
35  * OF SUCH DAMAGE.
36  *
37  * Author: Archie Cobbs <archie@freebsd.org>
38  *
39  * $Whistle: ng_parse.c,v 1.3 1999/11/29 01:43:48 archie Exp $
40  * $FreeBSD: src/sys/netgraph/ng_parse.c,v 1.3.2.8 2002/07/02 23:44:02 archie Exp $
41  * $DragonFly: src/sys/netgraph/netgraph/ng_parse.c,v 1.10 2008/01/05 14:02:39 swildner Exp $
42  */
43 
44 #include <sys/types.h>
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/errno.h>
48 #include <sys/malloc.h>
49 #include <sys/ctype.h>
50 
51 #include <netinet/in.h>
52 
53 #include <netgraph/ng_message.h>
54 #include <netgraph/netgraph.h>
55 #include <netgraph/ng_parse.h>
56 
57 /* Compute alignment for primitive integral types */
58 struct int16_temp {
59 	char	x;
60 	int16_t	y;
61 };
62 
63 struct int32_temp {
64 	char	x;
65 	int32_t	y;
66 };
67 
68 struct int64_temp {
69 	char	x;
70 	int64_t	y;
71 };
72 
73 #define INT8_ALIGNMENT		1
74 #define INT16_ALIGNMENT		((int)&((struct int16_temp *)0)->y)
75 #define INT32_ALIGNMENT		((int)&((struct int32_temp *)0)->y)
76 #define INT64_ALIGNMENT		((int)&((struct int64_temp *)0)->y)
77 
78 /* Output format for integral types */
79 #define INT_UNSIGNED		0
80 #define INT_SIGNED		1
81 #define INT_HEX			2
82 
83 /* Type of composite object: struct, array, or fixedarray */
84 enum comptype {
85 	CT_STRUCT,
86 	CT_ARRAY,
87 	CT_FIXEDARRAY,
88 };
89 
90 /* Composite types helper functions */
91 static int	ng_parse_composite(const struct ng_parse_type *type,
92 			const char *s, int *off, const u_char *start,
93 			u_char *const buf, int *buflen, enum comptype ctype);
94 static int	ng_unparse_composite(const struct ng_parse_type *type,
95 			const u_char *data, int *off, char *cbuf, int cbuflen,
96 			enum comptype ctype);
97 static int	ng_get_composite_elem_default(const struct ng_parse_type *type,
98 			int index, const u_char *start, u_char *buf,
99 			int *buflen, enum comptype ctype);
100 static int	ng_get_composite_len(const struct ng_parse_type *type,
101 			const u_char *start, const u_char *buf,
102 			enum comptype ctype);
103 static const	struct ng_parse_type *ng_get_composite_etype(const struct
104 			ng_parse_type *type, int index, enum comptype ctype);
105 static int	ng_parse_get_elem_pad(const struct ng_parse_type *type,
106 			int index, enum comptype ctype, int posn);
107 
108 /* Parsing helper functions */
109 static int	ng_parse_skip_value(const char *s, int off, int *lenp);
110 
111 /* Poor man's virtual method calls */
112 #define METHOD(t,m)	(ng_get_ ## m ## _method(t))
113 #define INVOKE(t,m)	(*METHOD(t,m))
114 
115 static ng_parse_t	*ng_get_parse_method(const struct ng_parse_type *t);
116 static ng_unparse_t	*ng_get_unparse_method(const struct ng_parse_type *t);
117 static ng_getDefault_t	*ng_get_getDefault_method(const
118 				struct ng_parse_type *t);
119 static ng_getAlign_t	*ng_get_getAlign_method(const struct ng_parse_type *t);
120 
121 #define ALIGNMENT(t)	(METHOD(t, getAlign) == NULL ? \
122 				0 : INVOKE(t, getAlign)(t))
123 
124 /* For converting binary to string */
125 #define NG_PARSE_APPEND(fmt, args...)				\
126 		do {						\
127 			int len;				\
128 								\
129 			len = ksnprintf((cbuf), (cbuflen),	\
130 				fmt , ## args);			\
131 			if (len >= (cbuflen))			\
132 				return (ERANGE);		\
133 			(cbuf) += len;				\
134 			(cbuflen) -= len;			\
135 		} while (0)
136 
137 /************************************************************************
138 			PUBLIC FUNCTIONS
139  ************************************************************************/
140 
141 /*
142  * Convert an ASCII string to binary according to the supplied type descriptor
143  */
144 int
145 ng_parse(const struct ng_parse_type *type,
146 	const char *string, int *off, u_char *buf, int *buflen)
147 {
148 	return INVOKE(type, parse)(type, string, off, buf, buf, buflen);
149 }
150 
151 /*
152  * Convert binary to an ASCII string according to the supplied type descriptor
153  */
154 int
155 ng_unparse(const struct ng_parse_type *type,
156 	const u_char *data, char *cbuf, int cbuflen)
157 {
158 	int off = 0;
159 
160 	return INVOKE(type, unparse)(type, data, &off, cbuf, cbuflen);
161 }
162 
163 /*
164  * Fill in the default value according to the supplied type descriptor
165  */
166 int
167 ng_parse_getDefault(const struct ng_parse_type *type, u_char *buf, int *buflen)
168 {
169 	ng_getDefault_t *const func = METHOD(type, getDefault);
170 
171 	if (func == NULL)
172 		return (EOPNOTSUPP);
173 	return (*func)(type, buf, buf, buflen);
174 }
175 
176 
177 /************************************************************************
178 			STRUCTURE TYPE
179  ************************************************************************/
180 
181 static int
182 ng_struct_parse(const struct ng_parse_type *type,
183 	const char *s, int *off, const u_char *const start,
184 	u_char *const buf, int *buflen)
185 {
186 	return ng_parse_composite(type, s, off, start, buf, buflen, CT_STRUCT);
187 }
188 
189 static int
190 ng_struct_unparse(const struct ng_parse_type *type,
191 	const u_char *data, int *off, char *cbuf, int cbuflen)
192 {
193 	return ng_unparse_composite(type, data, off, cbuf, cbuflen, CT_STRUCT);
194 }
195 
196 static int
197 ng_struct_getDefault(const struct ng_parse_type *type,
198 	const u_char *const start, u_char *buf, int *buflen)
199 {
200 	int off = 0;
201 
202 	return ng_parse_composite(type,
203 	    "{}", &off, start, buf, buflen, CT_STRUCT);
204 }
205 
206 static int
207 ng_struct_getAlign(const struct ng_parse_type *type)
208 {
209 	const struct ng_parse_struct_field *field;
210 	int align = 0;
211 
212 	for (field = type->info; field->name != NULL; field++) {
213 		int falign = ALIGNMENT(field->type);
214 
215 		if (falign > align)
216 			align = falign;
217 	}
218 	return align;
219 }
220 
221 const struct ng_parse_type ng_parse_struct_type = {
222 	NULL,
223 	NULL,
224 	NULL,
225 	ng_struct_parse,
226 	ng_struct_unparse,
227 	ng_struct_getDefault,
228 	ng_struct_getAlign
229 };
230 
231 /************************************************************************
232 			FIXED LENGTH ARRAY TYPE
233  ************************************************************************/
234 
235 static int
236 ng_fixedarray_parse(const struct ng_parse_type *type,
237 	const char *s, int *off, const u_char *const start,
238 	u_char *const buf, int *buflen)
239 {
240 	return ng_parse_composite(type,
241 	    s, off, start, buf, buflen, CT_FIXEDARRAY);
242 }
243 
244 static int
245 ng_fixedarray_unparse(const struct ng_parse_type *type,
246 	const u_char *data, int *off, char *cbuf, int cbuflen)
247 {
248 	return ng_unparse_composite(type,
249 		data, off, cbuf, cbuflen, CT_FIXEDARRAY);
250 }
251 
252 static int
253 ng_fixedarray_getDefault(const struct ng_parse_type *type,
254 	const u_char *const start, u_char *buf, int *buflen)
255 {
256 	int off = 0;
257 
258 	return ng_parse_composite(type,
259 	    "[]", &off, start, buf, buflen, CT_FIXEDARRAY);
260 }
261 
262 static int
263 ng_fixedarray_getAlign(const struct ng_parse_type *type)
264 {
265 	const struct ng_parse_fixedarray_info *fi = type->info;
266 
267 	return ALIGNMENT(fi->elementType);
268 }
269 
270 const struct ng_parse_type ng_parse_fixedarray_type = {
271 	NULL,
272 	NULL,
273 	NULL,
274 	ng_fixedarray_parse,
275 	ng_fixedarray_unparse,
276 	ng_fixedarray_getDefault,
277 	ng_fixedarray_getAlign
278 };
279 
280 /************************************************************************
281 			VARIABLE LENGTH ARRAY TYPE
282  ************************************************************************/
283 
284 static int
285 ng_array_parse(const struct ng_parse_type *type,
286 	const char *s, int *off, const u_char *const start,
287 	u_char *const buf, int *buflen)
288 {
289 	return ng_parse_composite(type, s, off, start, buf, buflen, CT_ARRAY);
290 }
291 
292 static int
293 ng_array_unparse(const struct ng_parse_type *type,
294 	const u_char *data, int *off, char *cbuf, int cbuflen)
295 {
296 	return ng_unparse_composite(type, data, off, cbuf, cbuflen, CT_ARRAY);
297 }
298 
299 static int
300 ng_array_getDefault(const struct ng_parse_type *type,
301 	const u_char *const start, u_char *buf, int *buflen)
302 {
303 	int off = 0;
304 
305 	return ng_parse_composite(type,
306 	    "[]", &off, start, buf, buflen, CT_ARRAY);
307 }
308 
309 static int
310 ng_array_getAlign(const struct ng_parse_type *type)
311 {
312 	const struct ng_parse_array_info *ai = type->info;
313 
314 	return ALIGNMENT(ai->elementType);
315 }
316 
317 const struct ng_parse_type ng_parse_array_type = {
318 	NULL,
319 	NULL,
320 	NULL,
321 	ng_array_parse,
322 	ng_array_unparse,
323 	ng_array_getDefault,
324 	ng_array_getAlign
325 };
326 
327 /************************************************************************
328 				INT8 TYPE
329  ************************************************************************/
330 
331 static int
332 ng_int8_parse(const struct ng_parse_type *type,
333 	const char *s, int *off, const u_char *const start,
334 	u_char *const buf, int *buflen)
335 {
336 	long val;
337 	int8_t val8;
338 	char *eptr;
339 
340 	val = strtol(s + *off, &eptr, 0);
341 	if (val < (int8_t)0x80 || val > (u_int8_t)0xff || eptr == s + *off)
342 		return (EINVAL);
343 	*off = eptr - s;
344 	val8 = (int8_t)val;
345 	bcopy(&val8, buf, sizeof(int8_t));
346 	*buflen = sizeof(int8_t);
347 	return (0);
348 }
349 
350 static int
351 ng_int8_unparse(const struct ng_parse_type *type,
352 	const u_char *data, int *off, char *cbuf, int cbuflen)
353 {
354 	const char *fmt;
355 	int fval;
356 	int8_t val;
357 
358 	bcopy(data + *off, &val, sizeof(int8_t));
359 	switch ((int)(intptr_t)type->info) {
360 	case INT_SIGNED:
361 		fmt = "%d";
362 		fval = val;
363 		break;
364 	case INT_UNSIGNED:
365 		fmt = "%u";
366 		fval = (u_int8_t)val;
367 		break;
368 	case INT_HEX:
369 		fmt = "0x%x";
370 		fval = (u_int8_t)val;
371 		break;
372 	default:
373 		panic("%s: unknown type", __func__);
374 	}
375 	NG_PARSE_APPEND(fmt, fval);
376 	*off += sizeof(int8_t);
377 	return (0);
378 }
379 
380 static int
381 ng_int8_getDefault(const struct ng_parse_type *type,
382 	const u_char *const start, u_char *buf, int *buflen)
383 {
384 	int8_t val;
385 
386 	if (*buflen < sizeof(int8_t))
387 		return (ERANGE);
388 	val = 0;
389 	bcopy(&val, buf, sizeof(int8_t));
390 	*buflen = sizeof(int8_t);
391 	return (0);
392 }
393 
394 static int
395 ng_int8_getAlign(const struct ng_parse_type *type)
396 {
397 	return INT8_ALIGNMENT;
398 }
399 
400 const struct ng_parse_type ng_parse_int8_type = {
401 	NULL,
402 	(void *)INT_SIGNED,
403 	NULL,
404 	ng_int8_parse,
405 	ng_int8_unparse,
406 	ng_int8_getDefault,
407 	ng_int8_getAlign
408 };
409 
410 const struct ng_parse_type ng_parse_uint8_type = {
411 	&ng_parse_int8_type,
412 	(void *)INT_UNSIGNED
413 };
414 
415 const struct ng_parse_type ng_parse_hint8_type = {
416 	&ng_parse_int8_type,
417 	(void *)INT_HEX
418 };
419 
420 /************************************************************************
421 				INT16 TYPE
422  ************************************************************************/
423 
424 static int
425 ng_int16_parse(const struct ng_parse_type *type,
426 	const char *s, int *off, const u_char *const start,
427 	u_char *const buf, int *buflen)
428 {
429 	long val;
430 	int16_t val16;
431 	char *eptr;
432 
433 	val = strtol(s + *off, &eptr, 0);
434 	if (val < (int16_t)0x8000
435 	    || val > (u_int16_t)0xffff || eptr == s + *off)
436 		return (EINVAL);
437 	*off = eptr - s;
438 	val16 = (int16_t)val;
439 	bcopy(&val16, buf, sizeof(int16_t));
440 	*buflen = sizeof(int16_t);
441 	return (0);
442 }
443 
444 static int
445 ng_int16_unparse(const struct ng_parse_type *type,
446 	const u_char *data, int *off, char *cbuf, int cbuflen)
447 {
448 	const char *fmt;
449 	int fval;
450 	int16_t val;
451 
452 	bcopy(data + *off, &val, sizeof(int16_t));
453 	switch ((int)(intptr_t)type->info) {
454 	case INT_SIGNED:
455 		fmt = "%d";
456 		fval = val;
457 		break;
458 	case INT_UNSIGNED:
459 		fmt = "%u";
460 		fval = (u_int16_t)val;
461 		break;
462 	case INT_HEX:
463 		fmt = "0x%x";
464 		fval = (u_int16_t)val;
465 		break;
466 	default:
467 		panic("%s: unknown type", __func__);
468 	}
469 	NG_PARSE_APPEND(fmt, fval);
470 	*off += sizeof(int16_t);
471 	return (0);
472 }
473 
474 static int
475 ng_int16_getDefault(const struct ng_parse_type *type,
476 	const u_char *const start, u_char *buf, int *buflen)
477 {
478 	int16_t val;
479 
480 	if (*buflen < sizeof(int16_t))
481 		return (ERANGE);
482 	val = 0;
483 	bcopy(&val, buf, sizeof(int16_t));
484 	*buflen = sizeof(int16_t);
485 	return (0);
486 }
487 
488 static int
489 ng_int16_getAlign(const struct ng_parse_type *type)
490 {
491 	return INT16_ALIGNMENT;
492 }
493 
494 const struct ng_parse_type ng_parse_int16_type = {
495 	NULL,
496 	(void *)INT_SIGNED,
497 	NULL,
498 	ng_int16_parse,
499 	ng_int16_unparse,
500 	ng_int16_getDefault,
501 	ng_int16_getAlign
502 };
503 
504 const struct ng_parse_type ng_parse_uint16_type = {
505 	&ng_parse_int16_type,
506 	(void *)INT_UNSIGNED
507 };
508 
509 const struct ng_parse_type ng_parse_hint16_type = {
510 	&ng_parse_int16_type,
511 	(void *)INT_HEX
512 };
513 
514 /************************************************************************
515 				INT32 TYPE
516  ************************************************************************/
517 
518 static int
519 ng_int32_parse(const struct ng_parse_type *type,
520 	const char *s, int *off, const u_char *const start,
521 	u_char *const buf, int *buflen)
522 {
523 	long val;			/* assumes long is at least 32 bits */
524 	int32_t val32;
525 	char *eptr;
526 
527 	val = strtol(s + *off, &eptr, 0);
528 	if (val < (int32_t)0x80000000
529 	    || val > (u_int32_t)0xffffffff || eptr == s + *off)
530 		return (EINVAL);
531 	*off = eptr - s;
532 	val32 = (int32_t)val;
533 	bcopy(&val32, buf, sizeof(int32_t));
534 	*buflen = sizeof(int32_t);
535 	return (0);
536 }
537 
538 static int
539 ng_int32_unparse(const struct ng_parse_type *type,
540 	const u_char *data, int *off, char *cbuf, int cbuflen)
541 {
542 	const char *fmt;
543 	long fval;
544 	int32_t val;
545 
546 	bcopy(data + *off, &val, sizeof(int32_t));
547 	switch ((int)(intptr_t)type->info) {
548 	case INT_SIGNED:
549 		fmt = "%ld";
550 		fval = val;
551 		break;
552 	case INT_UNSIGNED:
553 		fmt = "%lu";
554 		fval = (u_int32_t)val;
555 		break;
556 	case INT_HEX:
557 		fmt = "0x%lx";
558 		fval = (u_int32_t)val;
559 		break;
560 	default:
561 		panic("%s: unknown type", __func__);
562 	}
563 	NG_PARSE_APPEND(fmt, fval);
564 	*off += sizeof(int32_t);
565 	return (0);
566 }
567 
568 static int
569 ng_int32_getDefault(const struct ng_parse_type *type,
570 	const u_char *const start, u_char *buf, int *buflen)
571 {
572 	int32_t val;
573 
574 	if (*buflen < sizeof(int32_t))
575 		return (ERANGE);
576 	val = 0;
577 	bcopy(&val, buf, sizeof(int32_t));
578 	*buflen = sizeof(int32_t);
579 	return (0);
580 }
581 
582 static int
583 ng_int32_getAlign(const struct ng_parse_type *type)
584 {
585 	return INT32_ALIGNMENT;
586 }
587 
588 const struct ng_parse_type ng_parse_int32_type = {
589 	NULL,
590 	(void *)INT_SIGNED,
591 	NULL,
592 	ng_int32_parse,
593 	ng_int32_unparse,
594 	ng_int32_getDefault,
595 	ng_int32_getAlign
596 };
597 
598 const struct ng_parse_type ng_parse_uint32_type = {
599 	&ng_parse_int32_type,
600 	(void *)INT_UNSIGNED
601 };
602 
603 const struct ng_parse_type ng_parse_hint32_type = {
604 	&ng_parse_int32_type,
605 	(void *)INT_HEX
606 };
607 
608 /************************************************************************
609 				INT64 TYPE
610  ************************************************************************/
611 
612 static int
613 ng_int64_parse(const struct ng_parse_type *type,
614 	const char *s, int *off, const u_char *const start,
615 	u_char *const buf, int *buflen)
616 {
617 	quad_t val;
618 	int64_t val64;
619 	char *eptr;
620 
621 	val = strtoq(s + *off, &eptr, 0);
622 	if (eptr == s + *off)
623 		return (EINVAL);
624 	*off = eptr - s;
625 	val64 = (int64_t)val;
626 	bcopy(&val64, buf, sizeof(int64_t));
627 	*buflen = sizeof(int64_t);
628 	return (0);
629 }
630 
631 static int
632 ng_int64_unparse(const struct ng_parse_type *type,
633 	const u_char *data, int *off, char *cbuf, int cbuflen)
634 {
635 	const char *fmt;
636 	long long fval;
637 	int64_t val;
638 
639 	bcopy(data + *off, &val, sizeof(int64_t));
640 	switch ((int)(intptr_t)type->info) {
641 	case INT_SIGNED:
642 		fmt = "%lld";
643 		fval = val;
644 		break;
645 	case INT_UNSIGNED:
646 		fmt = "%llu";
647 		fval = (u_int64_t)val;
648 		break;
649 	case INT_HEX:
650 		fmt = "0x%llx";
651 		fval = (u_int64_t)val;
652 		break;
653 	default:
654 		panic("%s: unknown type", __func__);
655 	}
656 	NG_PARSE_APPEND(fmt, fval);
657 	*off += sizeof(int64_t);
658 	return (0);
659 }
660 
661 static int
662 ng_int64_getDefault(const struct ng_parse_type *type,
663 	const u_char *const start, u_char *buf, int *buflen)
664 {
665 	int64_t val;
666 
667 	if (*buflen < sizeof(int64_t))
668 		return (ERANGE);
669 	val = 0;
670 	bcopy(&val, buf, sizeof(int64_t));
671 	*buflen = sizeof(int64_t);
672 	return (0);
673 }
674 
675 static int
676 ng_int64_getAlign(const struct ng_parse_type *type)
677 {
678 	return INT64_ALIGNMENT;
679 }
680 
681 const struct ng_parse_type ng_parse_int64_type = {
682 	NULL,
683 	(void *)INT_SIGNED,
684 	NULL,
685 	ng_int64_parse,
686 	ng_int64_unparse,
687 	ng_int64_getDefault,
688 	ng_int64_getAlign
689 };
690 
691 const struct ng_parse_type ng_parse_uint64_type = {
692 	&ng_parse_int64_type,
693 	(void *)INT_UNSIGNED
694 };
695 
696 const struct ng_parse_type ng_parse_hint64_type = {
697 	&ng_parse_int64_type,
698 	(void *)INT_HEX
699 };
700 
701 /************************************************************************
702 				STRING TYPE
703  ************************************************************************/
704 
705 static int
706 ng_string_parse(const struct ng_parse_type *type,
707 	const char *s, int *off, const u_char *const start,
708 	u_char *const buf, int *buflen)
709 {
710 	char *sval;
711 	int len;
712 
713 	if ((sval = ng_get_string_token(s, off, &len)) == NULL)
714 		return (EINVAL);
715 	*off += len;
716 	len = strlen(sval) + 1;
717 	bcopy(sval, buf, len);
718 	FREE(sval, M_NETGRAPH);
719 	*buflen = len;
720 	return (0);
721 }
722 
723 static int
724 ng_string_unparse(const struct ng_parse_type *type,
725 	const u_char *data, int *off, char *cbuf, int cbuflen)
726 {
727 	const char *const raw = (const char *)data + *off;
728 	char *const s = ng_encode_string(raw);
729 
730 	if (s == NULL)
731 		return (ENOMEM);
732 	NG_PARSE_APPEND("%s", s);
733 	*off += strlen(raw) + 1;
734 	FREE(s, M_NETGRAPH);
735 	return (0);
736 }
737 
738 static int
739 ng_string_getDefault(const struct ng_parse_type *type,
740 	const u_char *const start, u_char *buf, int *buflen)
741 {
742 
743 	if (*buflen < 1)
744 		return (ERANGE);
745 	buf[0] = (u_char)'\0';
746 	*buflen = 1;
747 	return (0);
748 }
749 
750 const struct ng_parse_type ng_parse_string_type = {
751 	NULL,
752 	NULL,
753 	NULL,
754 	ng_string_parse,
755 	ng_string_unparse,
756 	ng_string_getDefault,
757 	NULL
758 };
759 
760 /************************************************************************
761 			FIXED BUFFER STRING TYPE
762  ************************************************************************/
763 
764 static int
765 ng_fixedstring_parse(const struct ng_parse_type *type,
766 	const char *s, int *off, const u_char *const start,
767 	u_char *const buf, int *buflen)
768 {
769 	const struct ng_parse_fixedstring_info *const fi = type->info;
770 	char *sval;
771 	int len;
772 
773 	if ((sval = ng_get_string_token(s, off, &len)) == NULL)
774 		return (EINVAL);
775 	if (strlen(sval) + 1 > fi->bufSize)
776 		return (E2BIG);
777 	*off += len;
778 	len = strlen(sval) + 1;
779 	bcopy(sval, buf, len);
780 	FREE(sval, M_NETGRAPH);
781 	bzero(buf + len, fi->bufSize - len);
782 	*buflen = fi->bufSize;
783 	return (0);
784 }
785 
786 static int
787 ng_fixedstring_unparse(const struct ng_parse_type *type,
788 	const u_char *data, int *off, char *cbuf, int cbuflen)
789 {
790 	const struct ng_parse_fixedstring_info *const fi = type->info;
791 	int error, temp = *off;
792 
793 	if ((error = ng_string_unparse(type, data, &temp, cbuf, cbuflen)) != 0)
794 		return (error);
795 	*off += fi->bufSize;
796 	return (0);
797 }
798 
799 static int
800 ng_fixedstring_getDefault(const struct ng_parse_type *type,
801 	const u_char *const start, u_char *buf, int *buflen)
802 {
803 	const struct ng_parse_fixedstring_info *const fi = type->info;
804 
805 	if (*buflen < fi->bufSize)
806 		return (ERANGE);
807 	bzero(buf, fi->bufSize);
808 	*buflen = fi->bufSize;
809 	return (0);
810 }
811 
812 const struct ng_parse_type ng_parse_fixedstring_type = {
813 	NULL,
814 	NULL,
815 	NULL,
816 	ng_fixedstring_parse,
817 	ng_fixedstring_unparse,
818 	ng_fixedstring_getDefault,
819 	NULL
820 };
821 
822 const struct ng_parse_fixedstring_info ng_parse_nodebuf_info = {
823 	NG_NODESIZ
824 };
825 const struct ng_parse_type ng_parse_nodebuf_type = {
826 	&ng_parse_fixedstring_type,
827 	&ng_parse_nodebuf_info
828 };
829 
830 const struct ng_parse_fixedstring_info ng_parse_hookbuf_info = {
831 	NG_HOOKSIZ
832 };
833 const struct ng_parse_type ng_parse_hookbuf_type = {
834 	&ng_parse_fixedstring_type,
835 	&ng_parse_hookbuf_info
836 };
837 
838 const struct ng_parse_fixedstring_info ng_parse_pathbuf_info = {
839 	NG_PATHSIZ
840 };
841 const struct ng_parse_type ng_parse_pathbuf_type = {
842 	&ng_parse_fixedstring_type,
843 	&ng_parse_pathbuf_info
844 };
845 
846 const struct ng_parse_fixedstring_info ng_parse_typebuf_info = {
847 	NG_TYPESIZ
848 };
849 const struct ng_parse_type ng_parse_typebuf_type = {
850 	&ng_parse_fixedstring_type,
851 	&ng_parse_typebuf_info
852 };
853 
854 const struct ng_parse_fixedstring_info ng_parse_cmdbuf_info = {
855 	NG_CMDSTRSIZ
856 };
857 const struct ng_parse_type ng_parse_cmdbuf_type = {
858 	&ng_parse_fixedstring_type,
859 	&ng_parse_cmdbuf_info
860 };
861 
862 /************************************************************************
863 			IP ADDRESS TYPE
864  ************************************************************************/
865 
866 static int
867 ng_ipaddr_parse(const struct ng_parse_type *type,
868 	const char *s, int *off, const u_char *const start,
869 	u_char *const buf, int *buflen)
870 {
871 	int i, error;
872 
873 	for (i = 0; i < 4; i++) {
874 		if ((error = ng_int8_parse(&ng_parse_int8_type,
875 		    s, off, start, buf + i, buflen)) != 0)
876 			return (error);
877 		if (i < 3 && s[*off] != '.')
878 			return (EINVAL);
879 		(*off)++;
880 	}
881 	*buflen = 4;
882 	return (0);
883 }
884 
885 static int
886 ng_ipaddr_unparse(const struct ng_parse_type *type,
887 	const u_char *data, int *off, char *cbuf, int cbuflen)
888 {
889 	struct in_addr ip;
890 
891 	bcopy(data + *off, &ip, sizeof(ip));
892 	NG_PARSE_APPEND("%d.%d.%d.%d", ((u_char *)&ip)[0],
893 	    ((u_char *)&ip)[1], ((u_char *)&ip)[2], ((u_char *)&ip)[3]);
894 	*off += sizeof(ip);
895 	return (0);
896 }
897 
898 static int
899 ng_ipaddr_getDefault(const struct ng_parse_type *type,
900 	const u_char *const start, u_char *buf, int *buflen)
901 {
902 	struct in_addr ip = { 0 };
903 
904 	if (*buflen < sizeof(ip))
905 		return (ERANGE);
906 	bcopy(&ip, buf, sizeof(ip));
907 	*buflen = sizeof(ip);
908 	return (0);
909 }
910 
911 const struct ng_parse_type ng_parse_ipaddr_type = {
912 	NULL,
913 	NULL,
914 	NULL,
915 	ng_ipaddr_parse,
916 	ng_ipaddr_unparse,
917 	ng_ipaddr_getDefault,
918 	ng_int32_getAlign
919 };
920 
921 /************************************************************************
922 			BYTE ARRAY TYPE
923  ************************************************************************/
924 
925 /* Get the length of a byte array */
926 static int
927 ng_parse_bytearray_subtype_getLength(const struct ng_parse_type *type,
928 	const u_char *start, const u_char *buf)
929 {
930 	ng_parse_array_getLength_t *const getLength = type->private;
931 
932 	return (*getLength)(type, start, buf);
933 }
934 
935 /* Byte array element type is hex int8 */
936 static const struct ng_parse_array_info ng_parse_bytearray_subtype_info = {
937 	&ng_parse_hint8_type,
938 	&ng_parse_bytearray_subtype_getLength,
939 	NULL
940 };
941 static const struct ng_parse_type ng_parse_bytearray_subtype = {
942 	&ng_parse_array_type,
943 	&ng_parse_bytearray_subtype_info
944 };
945 
946 static int
947 ng_bytearray_parse(const struct ng_parse_type *type,
948 	const char *s, int *off, const u_char *const start,
949 	u_char *const buf, int *buflen)
950 {
951 	char *str;
952 	int toklen;
953 
954 	/* We accept either an array of bytes or a string constant */
955 	if ((str = ng_get_string_token(s, off, &toklen)) != NULL) {
956 		ng_parse_array_getLength_t *const getLength = type->info;
957 		int arraylen, slen;
958 
959 		arraylen = (*getLength)(type, start, buf);
960 		if (arraylen > *buflen) {
961 			FREE(str, M_NETGRAPH);
962 			return (ERANGE);
963 		}
964 		slen = strlen(str) + 1;
965 		if (slen > arraylen) {
966 			FREE(str, M_NETGRAPH);
967 			return (E2BIG);
968 		}
969 		bcopy(str, buf, slen);
970 		bzero(buf + slen, arraylen - slen);
971 		FREE(str, M_NETGRAPH);
972 		*off += toklen;
973 		*buflen = arraylen;
974 		return (0);
975 	} else {
976 		struct ng_parse_type subtype;
977 
978 		subtype = ng_parse_bytearray_subtype;
979 		*(const void **)&subtype.private = type->info;
980 		return ng_array_parse(&subtype, s, off, start, buf, buflen);
981 	}
982 }
983 
984 static int
985 ng_bytearray_unparse(const struct ng_parse_type *type,
986 	const u_char *data, int *off, char *cbuf, int cbuflen)
987 {
988 	struct ng_parse_type subtype;
989 
990 	subtype = ng_parse_bytearray_subtype;
991 	*(const void **)&subtype.private = type->info;
992 	return ng_array_unparse(&subtype, data, off, cbuf, cbuflen);
993 }
994 
995 static int
996 ng_bytearray_getDefault(const struct ng_parse_type *type,
997 	const u_char *const start, u_char *buf, int *buflen)
998 {
999 	struct ng_parse_type subtype;
1000 
1001 	subtype = ng_parse_bytearray_subtype;
1002 	*(const void **)&subtype.private = type->info;
1003 	return ng_array_getDefault(&subtype, start, buf, buflen);
1004 }
1005 
1006 const struct ng_parse_type ng_parse_bytearray_type = {
1007 	NULL,
1008 	NULL,
1009 	NULL,
1010 	ng_bytearray_parse,
1011 	ng_bytearray_unparse,
1012 	ng_bytearray_getDefault,
1013 	NULL
1014 };
1015 
1016 /************************************************************************
1017 			STRUCT NG_MESG TYPE
1018  ************************************************************************/
1019 
1020 /* Get msg->header.arglen when "buf" is pointing to msg->data */
1021 static int
1022 ng_parse_ng_mesg_getLength(const struct ng_parse_type *type,
1023 	const u_char *start, const u_char *buf)
1024 {
1025 	const struct ng_mesg *msg;
1026 
1027 	msg = (const struct ng_mesg *)(buf - sizeof(*msg));
1028 	return msg->header.arglen;
1029 }
1030 
1031 /* Type for the variable length data portion of a struct ng_mesg */
1032 static const struct ng_parse_type ng_msg_data_type = {
1033 	&ng_parse_bytearray_type,
1034 	&ng_parse_ng_mesg_getLength
1035 };
1036 
1037 /* Type for the entire struct ng_mesg header with data section */
1038 static const struct ng_parse_struct_field ng_parse_ng_mesg_type_fields[]
1039 	= NG_GENERIC_NG_MESG_INFO(&ng_msg_data_type);
1040 const struct ng_parse_type ng_parse_ng_mesg_type = {
1041 	&ng_parse_struct_type,
1042 	&ng_parse_ng_mesg_type_fields,
1043 };
1044 
1045 /************************************************************************
1046 			COMPOSITE HELPER ROUTINES
1047  ************************************************************************/
1048 
1049 /*
1050  * Convert a structure or array from ASCII to binary
1051  */
1052 static int
1053 ng_parse_composite(const struct ng_parse_type *type, const char *s,
1054 	int *off, const u_char *const start, u_char *const buf, int *buflen,
1055 	const enum comptype ctype)
1056 {
1057 	const int num = ng_get_composite_len(type, start, buf, ctype);
1058 	int nextIndex = 0;		/* next implicit array index */
1059 	u_int index;			/* field or element index */
1060 	int *foff;			/* field value offsets in string */
1061 	int align, len, blen, error = 0;
1062 
1063 	/* Initialize */
1064 	MALLOC(foff, int *, num * sizeof(*foff), M_NETGRAPH, M_NOWAIT | M_ZERO);
1065 	if (foff == NULL) {
1066 		error = ENOMEM;
1067 		goto done;
1068 	}
1069 
1070 	/* Get opening brace/bracket */
1071 	if (ng_parse_get_token(s, off, &len)
1072 	    != (ctype == CT_STRUCT ? T_LBRACE : T_LBRACKET)) {
1073 		error = EINVAL;
1074 		goto done;
1075 	}
1076 	*off += len;
1077 
1078 	/* Get individual element value positions in the string */
1079 	for (;;) {
1080 		enum ng_parse_token tok;
1081 
1082 		/* Check for closing brace/bracket */
1083 		tok = ng_parse_get_token(s, off, &len);
1084 		if (tok == (ctype == CT_STRUCT ? T_RBRACE : T_RBRACKET)) {
1085 			*off += len;
1086 			break;
1087 		}
1088 
1089 		/* For arrays, the 'name' (ie, index) is optional, so
1090 		   distinguish name from values by seeing if the next
1091 		   token is an equals sign */
1092 		if (ctype != CT_STRUCT) {
1093 			int len2, off2;
1094 			char *eptr;
1095 
1096 			/* If an opening brace/bracket, index is implied */
1097 			if (tok == T_LBRACE || tok == T_LBRACKET) {
1098 				index = nextIndex++;
1099 				goto gotIndex;
1100 			}
1101 
1102 			/* Might be an index, might be a value, either way... */
1103 			if (tok != T_WORD) {
1104 				error = EINVAL;
1105 				goto done;
1106 			}
1107 
1108 			/* If no equals sign follows, index is implied */
1109 			off2 = *off + len;
1110 			if (ng_parse_get_token(s, &off2, &len2) != T_EQUALS) {
1111 				index = nextIndex++;
1112 				goto gotIndex;
1113 			}
1114 
1115 			/* Index was specified explicitly; parse it */
1116 			index = (u_int)strtoul(s + *off, &eptr, 0);
1117 			if (index < 0 || eptr - (s + *off) != len) {
1118 				error = EINVAL;
1119 				goto done;
1120 			}
1121 			nextIndex = index + 1;
1122 			*off += len + len2;
1123 gotIndex:
1124 			; /* avoid gcc3.x warning */
1125 		} else {			/* a structure field */
1126 			const struct ng_parse_struct_field *const
1127 			    fields = type->info;
1128 
1129 			/* Find the field by name (required) in field list */
1130 			if (tok != T_WORD) {
1131 				error = EINVAL;
1132 				goto done;
1133 			}
1134 			for (index = 0; index < num; index++) {
1135 				const struct ng_parse_struct_field *const
1136 				    field = &fields[index];
1137 
1138 				if (strncmp(&s[*off], field->name, len) == 0
1139 				    && field->name[len] == '\0')
1140 					break;
1141 			}
1142 			if (index == num) {
1143 				error = ENOENT;
1144 				goto done;
1145 			}
1146 			*off += len;
1147 
1148 			/* Get equals sign */
1149 			if (ng_parse_get_token(s, off, &len) != T_EQUALS) {
1150 				error = EINVAL;
1151 				goto done;
1152 			}
1153 			*off += len;
1154 		}
1155 
1156 		/* Check array index */
1157 		if (index >= num) {
1158 			error = E2BIG;
1159 			goto done;
1160 		}
1161 
1162 		/* Save value's position and skip over it for now */
1163 		if (foff[index] != 0) {
1164 			error = EALREADY;		/* duplicate */
1165 			goto done;
1166 		}
1167 		while (isspace(s[*off]))
1168 			(*off)++;
1169 		foff[index] = *off;
1170 		if ((error = ng_parse_skip_value(s, *off, &len)) != 0)
1171 			goto done;
1172 		*off += len;
1173 	}
1174 
1175 	/* Now build binary structure from supplied values and defaults */
1176 	for (blen = index = 0; index < num; index++) {
1177 		const struct ng_parse_type *const
1178 		    etype = ng_get_composite_etype(type, index, ctype);
1179 		int k, pad, vlen;
1180 
1181 		/* Zero-pad any alignment bytes */
1182 		pad = ng_parse_get_elem_pad(type, index, ctype, blen);
1183 		for (k = 0; k < pad; k++) {
1184 			if (blen >= *buflen) {
1185 				error = ERANGE;
1186 				goto done;
1187 			}
1188 			buf[blen++] = 0;
1189 		}
1190 
1191 		/* Get value */
1192 		vlen = *buflen - blen;
1193 		if (foff[index] == 0) {		/* use default value */
1194 			error = ng_get_composite_elem_default(type, index,
1195 			    start, buf + blen, &vlen, ctype);
1196 		} else {			/* parse given value */
1197 			*off = foff[index];
1198 			error = INVOKE(etype, parse)(etype,
1199 			    s, off, start, buf + blen, &vlen);
1200 		}
1201 		if (error != 0)
1202 			goto done;
1203 		blen += vlen;
1204 	}
1205 
1206 	/* Make total composite structure size a multiple of its alignment */
1207 	if ((align = ALIGNMENT(type)) != 0) {
1208 		while (blen % align != 0) {
1209 			if (blen >= *buflen) {
1210 				error = ERANGE;
1211 				goto done;
1212 			}
1213 			buf[blen++] = 0;
1214 		}
1215 	}
1216 
1217 	/* Done */
1218 	*buflen = blen;
1219 done:
1220 	if (foff != NULL)
1221 		FREE(foff, M_NETGRAPH);
1222 	return (error);
1223 }
1224 
1225 /*
1226  * Convert an array or structure from binary to ASCII
1227  */
1228 static int
1229 ng_unparse_composite(const struct ng_parse_type *type, const u_char *data,
1230 	int *off, char *cbuf, int cbuflen, const enum comptype ctype)
1231 {
1232 	const struct ng_mesg *const hdr
1233 	    = (const struct ng_mesg *)(data - sizeof(*hdr));
1234 	const int num = ng_get_composite_len(type, data, data + *off, ctype);
1235 	const int workSize = 20 * 1024;		/* XXX hard coded constant */
1236 	int nextIndex = 0, didOne = 0;
1237 	int error, index;
1238 	u_char *workBuf;
1239 
1240 	/* Get workspace for checking default values */
1241 	MALLOC(workBuf, u_char *, workSize, M_NETGRAPH, M_NOWAIT);
1242 	if (workBuf == NULL)
1243 		return (ENOMEM);
1244 
1245 	/* Opening brace/bracket */
1246 	NG_PARSE_APPEND("%c", (ctype == CT_STRUCT) ? '{' : '[');
1247 
1248 	/* Do each item */
1249 	for (index = 0; index < num; index++) {
1250 		const struct ng_parse_type *const
1251 		    etype = ng_get_composite_etype(type, index, ctype);
1252 
1253 		/* Skip any alignment pad bytes */
1254 		*off += ng_parse_get_elem_pad(type, index, ctype, *off);
1255 
1256 		/*
1257 		 * See if element is equal to its default value; skip if so.
1258 		 * Copy struct ng_mesg header for types that peek into it.
1259 		 */
1260 		if (sizeof(*hdr) + *off < workSize) {
1261 			int tempsize = workSize - sizeof(*hdr) - *off;
1262 
1263 			bcopy(hdr, workBuf, sizeof(*hdr) + *off);
1264 			if (ng_get_composite_elem_default(type, index, workBuf
1265 			      + sizeof(*hdr), workBuf + sizeof(*hdr) + *off,
1266 			      &tempsize, ctype) == 0
1267 			    && bcmp(workBuf + sizeof(*hdr) + *off,
1268 			      data + *off, tempsize) == 0) {
1269 				*off += tempsize;
1270 				continue;
1271 			}
1272 		}
1273 
1274 		/* Print name= */
1275 		NG_PARSE_APPEND(" ");
1276 		if (ctype != CT_STRUCT) {
1277 			if (index != nextIndex) {
1278 				nextIndex = index;
1279 				NG_PARSE_APPEND("%d=", index);
1280 			}
1281 			nextIndex++;
1282 		} else {
1283 			const struct ng_parse_struct_field *const
1284 			    fields = type->info;
1285 
1286 			NG_PARSE_APPEND("%s=", fields[index].name);
1287 		}
1288 
1289 		/* Print value */
1290 		if ((error = INVOKE(etype, unparse)
1291 		    (etype, data, off, cbuf, cbuflen)) != 0) {
1292 			FREE(workBuf, M_NETGRAPH);
1293 			return (error);
1294 		}
1295 		cbuflen -= strlen(cbuf);
1296 		cbuf += strlen(cbuf);
1297 		didOne = 1;
1298 	}
1299 	FREE(workBuf, M_NETGRAPH);
1300 
1301 	/* Closing brace/bracket */
1302 	NG_PARSE_APPEND("%s%c",
1303 	    didOne ? " " : "", (ctype == CT_STRUCT) ? '}' : ']');
1304 	return (0);
1305 }
1306 
1307 /*
1308  * Generate the default value for an element of an array or structure
1309  * Returns EOPNOTSUPP if default value is unspecified.
1310  */
1311 static int
1312 ng_get_composite_elem_default(const struct ng_parse_type *type,
1313 	int index, const u_char *const start, u_char *buf, int *buflen,
1314 	const enum comptype ctype)
1315 {
1316 	const struct ng_parse_type *etype;
1317 	ng_getDefault_t *func;
1318 
1319 	switch (ctype) {
1320 	case CT_STRUCT:
1321 		break;
1322 	case CT_ARRAY:
1323 	    {
1324 		const struct ng_parse_array_info *const ai = type->info;
1325 
1326 		if (ai->getDefault != NULL) {
1327 			return (*ai->getDefault)(type,
1328 			    index, start, buf, buflen);
1329 		}
1330 		break;
1331 	    }
1332 	case CT_FIXEDARRAY:
1333 	    {
1334 		const struct ng_parse_fixedarray_info *const fi = type->info;
1335 
1336 		if (*fi->getDefault != NULL) {
1337 			return (*fi->getDefault)(type,
1338 			    index, start, buf, buflen);
1339 		}
1340 		break;
1341 	    }
1342 	default:
1343 	    panic("%s", __func__);
1344 	}
1345 
1346 	/* Default to element type default */
1347 	etype = ng_get_composite_etype(type, index, ctype);
1348 	func = METHOD(etype, getDefault);
1349 	if (func == NULL)
1350 		return (EOPNOTSUPP);
1351 	return (*func)(etype, start, buf, buflen);
1352 }
1353 
1354 /*
1355  * Get the number of elements in a struct, variable or fixed array.
1356  */
1357 static int
1358 ng_get_composite_len(const struct ng_parse_type *type,
1359 	const u_char *const start, const u_char *buf,
1360 	const enum comptype ctype)
1361 {
1362 	switch (ctype) {
1363 	case CT_STRUCT:
1364 	    {
1365 		const struct ng_parse_struct_field *const fields = type->info;
1366 		int numFields = 0;
1367 
1368 		for (numFields = 0; ; numFields++) {
1369 			const struct ng_parse_struct_field *const
1370 				fi = &fields[numFields];
1371 
1372 			if (fi->name == NULL)
1373 				break;
1374 		}
1375 		return (numFields);
1376 	    }
1377 	case CT_ARRAY:
1378 	    {
1379 		const struct ng_parse_array_info *const ai = type->info;
1380 
1381 		return (*ai->getLength)(type, start, buf);
1382 	    }
1383 	case CT_FIXEDARRAY:
1384 	    {
1385 		const struct ng_parse_fixedarray_info *const fi = type->info;
1386 
1387 		return fi->length;
1388 	    }
1389 	default:
1390 	    panic("%s", __func__);
1391 	}
1392 	return (0);
1393 }
1394 
1395 /*
1396  * Return the type of the index'th element of a composite structure
1397  */
1398 static const struct ng_parse_type *
1399 ng_get_composite_etype(const struct ng_parse_type *type,
1400 	int index, const enum comptype ctype)
1401 {
1402 	const struct ng_parse_type *etype = NULL;
1403 
1404 	switch (ctype) {
1405 	case CT_STRUCT:
1406 	    {
1407 		const struct ng_parse_struct_field *const fields = type->info;
1408 
1409 		etype = fields[index].type;
1410 		break;
1411 	    }
1412 	case CT_ARRAY:
1413 	    {
1414 		const struct ng_parse_array_info *const ai = type->info;
1415 
1416 		etype = ai->elementType;
1417 		break;
1418 	    }
1419 	case CT_FIXEDARRAY:
1420 	    {
1421 		const struct ng_parse_fixedarray_info *const fi = type->info;
1422 
1423 		etype = fi->elementType;
1424 		break;
1425 	    }
1426 	default:
1427 	    panic("%s", __func__);
1428 	}
1429 	return (etype);
1430 }
1431 
1432 /*
1433  * Get the number of bytes to skip to align for the next
1434  * element in a composite structure.
1435  */
1436 static int
1437 ng_parse_get_elem_pad(const struct ng_parse_type *type,
1438 	int index, enum comptype ctype, int posn)
1439 {
1440 	const struct ng_parse_type *const
1441 	    etype = ng_get_composite_etype(type, index, ctype);
1442 	int align;
1443 
1444 	/* Get element's alignment, and possibly override */
1445 	align = ALIGNMENT(etype);
1446 	if (ctype == CT_STRUCT) {
1447 		const struct ng_parse_struct_field *const fields = type->info;
1448 
1449 		if (fields[index].alignment != 0)
1450 			align = fields[index].alignment;
1451 	}
1452 
1453 	/* Return number of bytes to skip to align */
1454 	return (align ? (align - (posn % align)) % align : 0);
1455 }
1456 
1457 /************************************************************************
1458 			PARSING HELPER ROUTINES
1459  ************************************************************************/
1460 
1461 /*
1462  * Skip over a value
1463  */
1464 static int
1465 ng_parse_skip_value(const char *s, int off0, int *lenp)
1466 {
1467 	int len, nbracket, nbrace;
1468 	int off = off0;
1469 
1470 	len = nbracket = nbrace = 0;
1471 	do {
1472 		switch (ng_parse_get_token(s, &off, &len)) {
1473 		case T_LBRACKET:
1474 			nbracket++;
1475 			break;
1476 		case T_LBRACE:
1477 			nbrace++;
1478 			break;
1479 		case T_RBRACKET:
1480 			if (nbracket-- == 0)
1481 				return (EINVAL);
1482 			break;
1483 		case T_RBRACE:
1484 			if (nbrace-- == 0)
1485 				return (EINVAL);
1486 			break;
1487 		case T_EOF:
1488 			return (EINVAL);
1489 		default:
1490 			break;
1491 		}
1492 		off += len;
1493 	} while (nbracket > 0 || nbrace > 0);
1494 	*lenp = off - off0;
1495 	return (0);
1496 }
1497 
1498 /*
1499  * Find the next token in the string, starting at offset *startp.
1500  * Returns the token type, with *startp pointing to the first char
1501  * and *lenp the length.
1502  */
1503 enum ng_parse_token
1504 ng_parse_get_token(const char *s, int *startp, int *lenp)
1505 {
1506 	char *t;
1507 	int i;
1508 
1509 	while (isspace(s[*startp]))
1510 		(*startp)++;
1511 	switch (s[*startp]) {
1512 	case '\0':
1513 		*lenp = 0;
1514 		return T_EOF;
1515 	case '{':
1516 		*lenp = 1;
1517 		return T_LBRACE;
1518 	case '}':
1519 		*lenp = 1;
1520 		return T_RBRACE;
1521 	case '[':
1522 		*lenp = 1;
1523 		return T_LBRACKET;
1524 	case ']':
1525 		*lenp = 1;
1526 		return T_RBRACKET;
1527 	case '=':
1528 		*lenp = 1;
1529 		return T_EQUALS;
1530 	case '"':
1531 		if ((t = ng_get_string_token(s, startp, lenp)) == NULL)
1532 			return T_ERROR;
1533 		FREE(t, M_NETGRAPH);
1534 		return T_STRING;
1535 	default:
1536 		for (i = *startp + 1; s[i] != '\0' && !isspace(s[i])
1537 		    && s[i] != '{' && s[i] != '}' && s[i] != '['
1538 		    && s[i] != ']' && s[i] != '=' && s[i] != '"'; i++)
1539 			;
1540 		*lenp = i - *startp;
1541 		return T_WORD;
1542 	}
1543 }
1544 
1545 /*
1546  * Get a string token, which must be enclosed in double quotes.
1547  * The normal C backslash escapes are recognized.
1548  */
1549 char *
1550 ng_get_string_token(const char *s, int *startp, int *lenp)
1551 {
1552 	char *cbuf, *p;
1553 	int start, off;
1554 
1555 	while (isspace(s[*startp]))
1556 		(*startp)++;
1557 	start = *startp;
1558 	if (s[*startp] != '"')
1559 		return (NULL);
1560 	MALLOC(cbuf, char *, strlen(s + start), M_NETGRAPH, M_NOWAIT);
1561 	if (cbuf == NULL)
1562 		return (NULL);
1563 	strcpy(cbuf, s + start + 1);
1564 	for (off = 1, p = cbuf; *p != '\0'; off++, p++) {
1565 		if (*p == '"') {
1566 			*p = '\0';
1567 			*lenp = off + 1;
1568 			return (cbuf);
1569 		} else if (p[0] == '\\' && p[1] != '\0') {
1570 			int x, k;
1571 			char *v;
1572 
1573 			strcpy(p, p + 1);
1574 			v = p;
1575 			switch (*p) {
1576 			case 't':
1577 				*v = '\t';
1578 				off++;
1579 				continue;
1580 			case 'n':
1581 				*v = '\n';
1582 				off++;
1583 				continue;
1584 			case 'r':
1585 				*v = '\r';
1586 				off++;
1587 				continue;
1588 			case 'v':
1589 				*v =  '\v';
1590 				off++;
1591 				continue;
1592 			case 'f':
1593 				*v =  '\f';
1594 				off++;
1595 				continue;
1596 			case '"':
1597 				*v =  '"';
1598 				off++;
1599 				continue;
1600 			case '0': case '1': case '2': case '3':
1601 			case '4': case '5': case '6': case '7':
1602 				for (x = k = 0;
1603 				    k < 3 && *v >= '0' && *v <= '7'; v++) {
1604 					x = (x << 3) + (*v - '0');
1605 					off++;
1606 				}
1607 				*--v = (char)x;
1608 				break;
1609 			case 'x':
1610 				for (v++, x = k = 0;
1611 				    k < 2 && isxdigit(*v); v++) {
1612 					x = (x << 4) + (isdigit(*v) ?
1613 					      (*v - '0') :
1614 					      (tolower(*v) - 'a' + 10));
1615 					off++;
1616 				}
1617 				*--v = (char)x;
1618 				break;
1619 			default:
1620 				continue;
1621 			}
1622 			strcpy(p, v);
1623 		}
1624 	}
1625 	return (NULL);		/* no closing quote */
1626 }
1627 
1628 /*
1629  * Encode a string so it can be safely put in double quotes.
1630  * Caller must free the result.
1631  */
1632 char *
1633 ng_encode_string(const char *raw)
1634 {
1635 	char *cbuf;
1636 	int off = 0;
1637 
1638 	MALLOC(cbuf, char *, strlen(raw) * 4 + 3, M_NETGRAPH, M_NOWAIT);
1639 	if (cbuf == NULL)
1640 		return (NULL);
1641 	cbuf[off++] = '"';
1642 	for ( ; *raw != '\0'; raw++) {
1643 		switch (*raw) {
1644 		case '\t':
1645 			cbuf[off++] = '\\';
1646 			cbuf[off++] = 't';
1647 			break;
1648 		case '\f':
1649 			cbuf[off++] = '\\';
1650 			cbuf[off++] = 'f';
1651 			break;
1652 		case '\n':
1653 			cbuf[off++] = '\\';
1654 			cbuf[off++] = 'n';
1655 			break;
1656 		case '\r':
1657 			cbuf[off++] = '\\';
1658 			cbuf[off++] = 'r';
1659 			break;
1660 		case '\v':
1661 			cbuf[off++] = '\\';
1662 			cbuf[off++] = 'v';
1663 			break;
1664 		case '"':
1665 		case '\\':
1666 			cbuf[off++] = '\\';
1667 			cbuf[off++] = *raw;
1668 			break;
1669 		default:
1670 			if (*raw < 0x20 || *raw > 0x7e) {
1671 				off += ksprintf(cbuf + off,
1672 				    "\\x%02x", (u_char)*raw);
1673 				break;
1674 			}
1675 			cbuf[off++] = *raw;
1676 			break;
1677 		}
1678 	}
1679 	cbuf[off++] = '"';
1680 	cbuf[off] = '\0';
1681 	return (cbuf);
1682 }
1683 
1684 /************************************************************************
1685 			VIRTUAL METHOD LOOKUP
1686  ************************************************************************/
1687 
1688 static ng_parse_t *
1689 ng_get_parse_method(const struct ng_parse_type *t)
1690 {
1691 	while (t != NULL && t->parse == NULL)
1692 		t = t->supertype;
1693 	return (t ? t->parse : NULL);
1694 }
1695 
1696 static ng_unparse_t *
1697 ng_get_unparse_method(const struct ng_parse_type *t)
1698 {
1699 	while (t != NULL && t->unparse == NULL)
1700 		t = t->supertype;
1701 	return (t ? t->unparse : NULL);
1702 }
1703 
1704 static ng_getDefault_t *
1705 ng_get_getDefault_method(const struct ng_parse_type *t)
1706 {
1707 	while (t != NULL && t->getDefault == NULL)
1708 		t = t->supertype;
1709 	return (t ? t->getDefault : NULL);
1710 }
1711 
1712 static ng_getAlign_t *
1713 ng_get_getAlign_method(const struct ng_parse_type *t)
1714 {
1715 	while (t != NULL && t->getAlign == NULL)
1716 		t = t->supertype;
1717 	return (t ? t->getAlign : NULL);
1718 }
1719 
1720