xref: /freebsd/sys/netgraph/ng_parse.c (revision 911f0260390e18cf85f3dbf2c719b593efdc1e3c)
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 			STRUCTURE TYPE
180  ************************************************************************/
181 
182 static int
183 ng_struct_parse(const struct ng_parse_type *type,
184 	const char *s, int *off, const u_char *const start,
185 	u_char *const buf, int *buflen)
186 {
187 	return ng_parse_composite(type, s, off, start, buf, buflen, CT_STRUCT);
188 }
189 
190 static int
191 ng_struct_unparse(const struct ng_parse_type *type,
192 	const u_char *data, int *off, char *cbuf, int cbuflen)
193 {
194 	return ng_unparse_composite(type, data, off, cbuf, cbuflen, CT_STRUCT);
195 }
196 
197 static int
198 ng_struct_getDefault(const struct ng_parse_type *type,
199 	const u_char *const start, u_char *buf, int *buflen)
200 {
201 	int off = 0;
202 
203 	return ng_parse_composite(type,
204 	    "{}", &off, start, buf, buflen, CT_STRUCT);
205 }
206 
207 static int
208 ng_struct_getAlign(const struct ng_parse_type *type)
209 {
210 	const struct ng_parse_struct_field *field;
211 	int align = 0;
212 
213 	for (field = type->info; field->name != NULL; field++) {
214 		int falign = ALIGNMENT(field->type);
215 
216 		if (falign > align)
217 			align = falign;
218 	}
219 	return align;
220 }
221 
222 const struct ng_parse_type ng_parse_struct_type = {
223 	NULL,
224 	NULL,
225 	NULL,
226 	ng_struct_parse,
227 	ng_struct_unparse,
228 	ng_struct_getDefault,
229 	ng_struct_getAlign
230 };
231 
232 /************************************************************************
233 			FIXED LENGTH ARRAY TYPE
234  ************************************************************************/
235 
236 static int
237 ng_fixedarray_parse(const struct ng_parse_type *type,
238 	const char *s, int *off, const u_char *const start,
239 	u_char *const buf, int *buflen)
240 {
241 	return ng_parse_composite(type,
242 	    s, off, start, buf, buflen, CT_FIXEDARRAY);
243 }
244 
245 static int
246 ng_fixedarray_unparse(const struct ng_parse_type *type,
247 	const u_char *data, int *off, char *cbuf, int cbuflen)
248 {
249 	return ng_unparse_composite(type,
250 		data, off, cbuf, cbuflen, CT_FIXEDARRAY);
251 }
252 
253 static int
254 ng_fixedarray_getDefault(const struct ng_parse_type *type,
255 	const u_char *const start, u_char *buf, int *buflen)
256 {
257 	int off = 0;
258 
259 	return ng_parse_composite(type,
260 	    "[]", &off, start, buf, buflen, CT_FIXEDARRAY);
261 }
262 
263 static int
264 ng_fixedarray_getAlign(const struct ng_parse_type *type)
265 {
266 	const struct ng_parse_fixedarray_info *fi = type->info;
267 
268 	return ALIGNMENT(fi->elementType);
269 }
270 
271 const struct ng_parse_type ng_parse_fixedarray_type = {
272 	NULL,
273 	NULL,
274 	NULL,
275 	ng_fixedarray_parse,
276 	ng_fixedarray_unparse,
277 	ng_fixedarray_getDefault,
278 	ng_fixedarray_getAlign
279 };
280 
281 /************************************************************************
282 			VARIABLE LENGTH ARRAY TYPE
283  ************************************************************************/
284 
285 static int
286 ng_array_parse(const struct ng_parse_type *type,
287 	const char *s, int *off, const u_char *const start,
288 	u_char *const buf, int *buflen)
289 {
290 	return ng_parse_composite(type, s, off, start, buf, buflen, CT_ARRAY);
291 }
292 
293 static int
294 ng_array_unparse(const struct ng_parse_type *type,
295 	const u_char *data, int *off, char *cbuf, int cbuflen)
296 {
297 	return ng_unparse_composite(type, data, off, cbuf, cbuflen, CT_ARRAY);
298 }
299 
300 static int
301 ng_array_getDefault(const struct ng_parse_type *type,
302 	const u_char *const start, u_char *buf, int *buflen)
303 {
304 	int off = 0;
305 
306 	return ng_parse_composite(type,
307 	    "[]", &off, start, buf, buflen, CT_ARRAY);
308 }
309 
310 static int
311 ng_array_getAlign(const struct ng_parse_type *type)
312 {
313 	const struct ng_parse_array_info *ai = type->info;
314 
315 	return ALIGNMENT(ai->elementType);
316 }
317 
318 const struct ng_parse_type ng_parse_array_type = {
319 	NULL,
320 	NULL,
321 	NULL,
322 	ng_array_parse,
323 	ng_array_unparse,
324 	ng_array_getDefault,
325 	ng_array_getAlign
326 };
327 
328 /************************************************************************
329 				INT8 TYPE
330  ************************************************************************/
331 
332 static int
333 ng_int8_parse(const struct ng_parse_type *type,
334 	const char *s, int *off, const u_char *const start,
335 	u_char *const buf, int *buflen)
336 {
337 	long val;
338 	int8_t val8;
339 	char *eptr;
340 
341 	val = strtol(s + *off, &eptr, 0);
342 	if (val < (int8_t)0x80 || val > (u_int8_t)0xff || eptr == s + *off)
343 		return (EINVAL);
344 	*off = eptr - s;
345 	val8 = (int8_t)val;
346 	bcopy(&val8, buf, sizeof(int8_t));
347 	*buflen = sizeof(int8_t);
348 	return (0);
349 }
350 
351 static int
352 ng_int8_unparse(const struct ng_parse_type *type,
353 	const u_char *data, int *off, char *cbuf, int cbuflen)
354 {
355 	const char *fmt;
356 	int fval;
357 	int error;
358 	int8_t val;
359 
360 	bcopy(data + *off, &val, sizeof(int8_t));
361 	switch ((intptr_t)type->info) {
362 	case INT_SIGNED:
363 		fmt = "%d";
364 		fval = val;
365 		break;
366 	case INT_UNSIGNED:
367 		fmt = "%u";
368 		fval = (u_int8_t)val;
369 		break;
370 	case INT_HEX:
371 		fmt = "0x%x";
372 		fval = (u_int8_t)val;
373 		break;
374 	default:
375 		panic("%s: unknown type", __func__);
376 	}
377 	if ((error = ng_parse_append(&cbuf, &cbuflen, fmt, fval)) != 0)
378 		return (error);
379 	*off += sizeof(int8_t);
380 	return (0);
381 }
382 
383 static int
384 ng_int8_getDefault(const struct ng_parse_type *type,
385 	const u_char *const start, u_char *buf, int *buflen)
386 {
387 	int8_t val;
388 
389 	if (*buflen < sizeof(int8_t))
390 		return (ERANGE);
391 	val = 0;
392 	bcopy(&val, buf, sizeof(int8_t));
393 	*buflen = sizeof(int8_t);
394 	return (0);
395 }
396 
397 static int
398 ng_int8_getAlign(const struct ng_parse_type *type)
399 {
400 	return INT8_ALIGNMENT;
401 }
402 
403 const struct ng_parse_type ng_parse_int8_type = {
404 	NULL,
405 	(void *)INT_SIGNED,
406 	NULL,
407 	ng_int8_parse,
408 	ng_int8_unparse,
409 	ng_int8_getDefault,
410 	ng_int8_getAlign
411 };
412 
413 const struct ng_parse_type ng_parse_uint8_type = {
414 	&ng_parse_int8_type,
415 	(void *)INT_UNSIGNED
416 };
417 
418 const struct ng_parse_type ng_parse_hint8_type = {
419 	&ng_parse_int8_type,
420 	(void *)INT_HEX
421 };
422 
423 /************************************************************************
424 				INT16 TYPE
425  ************************************************************************/
426 
427 static int
428 ng_int16_parse(const struct ng_parse_type *type,
429 	const char *s, int *off, const u_char *const start,
430 	u_char *const buf, int *buflen)
431 {
432 	long val;
433 	int16_t val16;
434 	char *eptr;
435 
436 	val = strtol(s + *off, &eptr, 0);
437 	if (val < (int16_t)0x8000
438 	    || val > (u_int16_t)0xffff || eptr == s + *off)
439 		return (EINVAL);
440 	*off = eptr - s;
441 	val16 = (int16_t)val;
442 	bcopy(&val16, buf, sizeof(int16_t));
443 	*buflen = sizeof(int16_t);
444 	return (0);
445 }
446 
447 static int
448 ng_int16_unparse(const struct ng_parse_type *type,
449 	const u_char *data, int *off, char *cbuf, int cbuflen)
450 {
451 	const char *fmt;
452 	int fval;
453 	int error;
454 	int16_t val;
455 
456 	bcopy(data + *off, &val, sizeof(int16_t));
457 	switch ((intptr_t)type->info) {
458 	case INT_SIGNED:
459 		fmt = "%d";
460 		fval = val;
461 		break;
462 	case INT_UNSIGNED:
463 		fmt = "%u";
464 		fval = (u_int16_t)val;
465 		break;
466 	case INT_HEX:
467 		fmt = "0x%x";
468 		fval = (u_int16_t)val;
469 		break;
470 	default:
471 		panic("%s: unknown type", __func__);
472 	}
473 	if ((error = ng_parse_append(&cbuf, &cbuflen, fmt, fval)) != 0)
474 		return (error);
475 	*off += sizeof(int16_t);
476 	return (0);
477 }
478 
479 static int
480 ng_int16_getDefault(const struct ng_parse_type *type,
481 	const u_char *const start, u_char *buf, int *buflen)
482 {
483 	int16_t val;
484 
485 	if (*buflen < sizeof(int16_t))
486 		return (ERANGE);
487 	val = 0;
488 	bcopy(&val, buf, sizeof(int16_t));
489 	*buflen = sizeof(int16_t);
490 	return (0);
491 }
492 
493 static int
494 ng_int16_getAlign(const struct ng_parse_type *type)
495 {
496 	return INT16_ALIGNMENT;
497 }
498 
499 const struct ng_parse_type ng_parse_int16_type = {
500 	NULL,
501 	(void *)INT_SIGNED,
502 	NULL,
503 	ng_int16_parse,
504 	ng_int16_unparse,
505 	ng_int16_getDefault,
506 	ng_int16_getAlign
507 };
508 
509 const struct ng_parse_type ng_parse_uint16_type = {
510 	&ng_parse_int16_type,
511 	(void *)INT_UNSIGNED
512 };
513 
514 const struct ng_parse_type ng_parse_hint16_type = {
515 	&ng_parse_int16_type,
516 	(void *)INT_HEX
517 };
518 
519 /************************************************************************
520 				INT32 TYPE
521  ************************************************************************/
522 
523 static int
524 ng_int32_parse(const struct ng_parse_type *type,
525 	const char *s, int *off, const u_char *const start,
526 	u_char *const buf, int *buflen)
527 {
528 	long val;			/* assumes long is at least 32 bits */
529 	int32_t val32;
530 	char *eptr;
531 
532 	if ((intptr_t)type->info == INT_SIGNED)
533 		val = strtol(s + *off, &eptr, 0);
534 	else
535 		val = strtoul(s + *off, &eptr, 0);
536 	if (val < (int32_t)0x80000000
537 	    || val > (u_int32_t)0xffffffff || eptr == s + *off)
538 		return (EINVAL);
539 	*off = eptr - s;
540 	val32 = (int32_t)val;
541 	bcopy(&val32, buf, sizeof(int32_t));
542 	*buflen = sizeof(int32_t);
543 	return (0);
544 }
545 
546 static int
547 ng_int32_unparse(const struct ng_parse_type *type,
548 	const u_char *data, int *off, char *cbuf, int cbuflen)
549 {
550 	const char *fmt;
551 	long fval;
552 	int error;
553 	int32_t val;
554 
555 	bcopy(data + *off, &val, sizeof(int32_t));
556 	switch ((intptr_t)type->info) {
557 	case INT_SIGNED:
558 		fmt = "%ld";
559 		fval = val;
560 		break;
561 	case INT_UNSIGNED:
562 		fmt = "%lu";
563 		fval = (u_int32_t)val;
564 		break;
565 	case INT_HEX:
566 		fmt = "0x%lx";
567 		fval = (u_int32_t)val;
568 		break;
569 	default:
570 		panic("%s: unknown type", __func__);
571 	}
572 	if ((error = ng_parse_append(&cbuf, &cbuflen, fmt, fval)) != 0)
573 		return (error);
574 	*off += sizeof(int32_t);
575 	return (0);
576 }
577 
578 static int
579 ng_int32_getDefault(const struct ng_parse_type *type,
580 	const u_char *const start, u_char *buf, int *buflen)
581 {
582 	int32_t val;
583 
584 	if (*buflen < sizeof(int32_t))
585 		return (ERANGE);
586 	val = 0;
587 	bcopy(&val, buf, sizeof(int32_t));
588 	*buflen = sizeof(int32_t);
589 	return (0);
590 }
591 
592 static int
593 ng_int32_getAlign(const struct ng_parse_type *type)
594 {
595 	return INT32_ALIGNMENT;
596 }
597 
598 const struct ng_parse_type ng_parse_int32_type = {
599 	NULL,
600 	(void *)INT_SIGNED,
601 	NULL,
602 	ng_int32_parse,
603 	ng_int32_unparse,
604 	ng_int32_getDefault,
605 	ng_int32_getAlign
606 };
607 
608 const struct ng_parse_type ng_parse_uint32_type = {
609 	&ng_parse_int32_type,
610 	(void *)INT_UNSIGNED
611 };
612 
613 const struct ng_parse_type ng_parse_hint32_type = {
614 	&ng_parse_int32_type,
615 	(void *)INT_HEX
616 };
617 
618 /************************************************************************
619 				INT64 TYPE
620  ************************************************************************/
621 
622 static int
623 ng_int64_parse(const struct ng_parse_type *type,
624 	const char *s, int *off, const u_char *const start,
625 	u_char *const buf, int *buflen)
626 {
627 	quad_t val;
628 	int64_t val64;
629 	char *eptr;
630 
631 	val = strtoq(s + *off, &eptr, 0);
632 	if (eptr == s + *off)
633 		return (EINVAL);
634 	*off = eptr - s;
635 	val64 = (int64_t)val;
636 	bcopy(&val64, buf, sizeof(int64_t));
637 	*buflen = sizeof(int64_t);
638 	return (0);
639 }
640 
641 static int
642 ng_int64_unparse(const struct ng_parse_type *type,
643 	const u_char *data, int *off, char *cbuf, int cbuflen)
644 {
645 	const char *fmt;
646 	long long fval;
647 	int64_t val;
648 	int error;
649 
650 	bcopy(data + *off, &val, sizeof(int64_t));
651 	switch ((intptr_t)type->info) {
652 	case INT_SIGNED:
653 		fmt = "%lld";
654 		fval = val;
655 		break;
656 	case INT_UNSIGNED:
657 		fmt = "%llu";
658 		fval = (u_int64_t)val;
659 		break;
660 	case INT_HEX:
661 		fmt = "0x%llx";
662 		fval = (u_int64_t)val;
663 		break;
664 	default:
665 		panic("%s: unknown type", __func__);
666 	}
667 	if ((error = ng_parse_append(&cbuf, &cbuflen, fmt, fval)) != 0)
668 		return (error);
669 	*off += sizeof(int64_t);
670 	return (0);
671 }
672 
673 static int
674 ng_int64_getDefault(const struct ng_parse_type *type,
675 	const u_char *const start, u_char *buf, int *buflen)
676 {
677 	int64_t val;
678 
679 	if (*buflen < sizeof(int64_t))
680 		return (ERANGE);
681 	val = 0;
682 	bcopy(&val, buf, sizeof(int64_t));
683 	*buflen = sizeof(int64_t);
684 	return (0);
685 }
686 
687 static int
688 ng_int64_getAlign(const struct ng_parse_type *type)
689 {
690 	return INT64_ALIGNMENT;
691 }
692 
693 const struct ng_parse_type ng_parse_int64_type = {
694 	NULL,
695 	(void *)INT_SIGNED,
696 	NULL,
697 	ng_int64_parse,
698 	ng_int64_unparse,
699 	ng_int64_getDefault,
700 	ng_int64_getAlign
701 };
702 
703 const struct ng_parse_type ng_parse_uint64_type = {
704 	&ng_parse_int64_type,
705 	(void *)INT_UNSIGNED
706 };
707 
708 const struct ng_parse_type ng_parse_hint64_type = {
709 	&ng_parse_int64_type,
710 	(void *)INT_HEX
711 };
712 
713 /************************************************************************
714 				STRING TYPE
715  ************************************************************************/
716 
717 static int
718 ng_string_parse(const struct ng_parse_type *type,
719 	const char *s, int *off, const u_char *const start,
720 	u_char *const buf, int *buflen)
721 {
722 	char *sval;
723 	int len;
724 	int slen;
725 
726 	if ((sval = ng_get_string_token(s, off, &len, &slen)) == NULL)
727 		return (EINVAL);
728 	*off += len;
729 	bcopy(sval, buf, slen + 1);
730 	free(sval, M_NETGRAPH_PARSE);
731 	*buflen = slen + 1;
732 	return (0);
733 }
734 
735 static int
736 ng_string_unparse(const struct ng_parse_type *type,
737 	const u_char *data, int *off, char *cbuf, int cbuflen)
738 {
739 	const char *const raw = (const char *)data + *off;
740 	char *const s = ng_encode_string(raw, strlen(raw));
741 	int error;
742 
743 	if (s == NULL)
744 		return (ENOMEM);
745 	if ((error = ng_parse_append(&cbuf, &cbuflen, "%s", s)) != 0) {
746 		free(s, M_NETGRAPH_PARSE);
747 		return (error);
748 	}
749 	*off += strlen(raw) + 1;
750 	free(s, M_NETGRAPH_PARSE);
751 	return (0);
752 }
753 
754 static int
755 ng_string_getDefault(const struct ng_parse_type *type,
756 	const u_char *const start, u_char *buf, int *buflen)
757 {
758 
759 	if (*buflen < 1)
760 		return (ERANGE);
761 	buf[0] = (u_char)'\0';
762 	*buflen = 1;
763 	return (0);
764 }
765 
766 const struct ng_parse_type ng_parse_string_type = {
767 	NULL,
768 	NULL,
769 	NULL,
770 	ng_string_parse,
771 	ng_string_unparse,
772 	ng_string_getDefault,
773 	NULL
774 };
775 
776 /************************************************************************
777 			FIXED BUFFER STRING TYPE
778  ************************************************************************/
779 
780 static int
781 ng_fixedstring_parse(const struct ng_parse_type *type,
782 	const char *s, int *off, const u_char *const start,
783 	u_char *const buf, int *buflen)
784 {
785 	const struct ng_parse_fixedstring_info *const fi = type->info;
786 	char *sval;
787 	int len;
788 	int slen;
789 
790 	if ((sval = ng_get_string_token(s, off, &len, &slen)) == NULL)
791 		return (EINVAL);
792 	if (slen + 1 > fi->bufSize) {
793 		free(sval, M_NETGRAPH_PARSE);
794 		return (E2BIG);
795 	}
796 	*off += len;
797 	bcopy(sval, buf, slen);
798 	free(sval, M_NETGRAPH_PARSE);
799 	bzero(buf + slen, fi->bufSize - slen);
800 	*buflen = fi->bufSize;
801 	return (0);
802 }
803 
804 static int
805 ng_fixedstring_unparse(const struct ng_parse_type *type,
806 	const u_char *data, int *off, char *cbuf, int cbuflen)
807 {
808 	const struct ng_parse_fixedstring_info *const fi = type->info;
809 	int error, temp = *off;
810 
811 	if ((error = ng_string_unparse(type, data, &temp, cbuf, cbuflen)) != 0)
812 		return (error);
813 	*off += fi->bufSize;
814 	return (0);
815 }
816 
817 static int
818 ng_fixedstring_getDefault(const struct ng_parse_type *type,
819 	const u_char *const start, u_char *buf, int *buflen)
820 {
821 	const struct ng_parse_fixedstring_info *const fi = type->info;
822 
823 	if (*buflen < fi->bufSize)
824 		return (ERANGE);
825 	bzero(buf, fi->bufSize);
826 	*buflen = fi->bufSize;
827 	return (0);
828 }
829 
830 const struct ng_parse_type ng_parse_fixedstring_type = {
831 	NULL,
832 	NULL,
833 	NULL,
834 	ng_fixedstring_parse,
835 	ng_fixedstring_unparse,
836 	ng_fixedstring_getDefault,
837 	NULL
838 };
839 
840 const struct ng_parse_fixedstring_info ng_parse_nodebuf_info = {
841 	NG_NODESIZ
842 };
843 const struct ng_parse_type ng_parse_nodebuf_type = {
844 	&ng_parse_fixedstring_type,
845 	&ng_parse_nodebuf_info
846 };
847 
848 const struct ng_parse_fixedstring_info ng_parse_hookbuf_info = {
849 	NG_HOOKSIZ
850 };
851 const struct ng_parse_type ng_parse_hookbuf_type = {
852 	&ng_parse_fixedstring_type,
853 	&ng_parse_hookbuf_info
854 };
855 
856 const struct ng_parse_fixedstring_info ng_parse_pathbuf_info = {
857 	NG_PATHSIZ
858 };
859 const struct ng_parse_type ng_parse_pathbuf_type = {
860 	&ng_parse_fixedstring_type,
861 	&ng_parse_pathbuf_info
862 };
863 
864 const struct ng_parse_fixedstring_info ng_parse_typebuf_info = {
865 	NG_TYPESIZ
866 };
867 const struct ng_parse_type ng_parse_typebuf_type = {
868 	&ng_parse_fixedstring_type,
869 	&ng_parse_typebuf_info
870 };
871 
872 const struct ng_parse_fixedstring_info ng_parse_cmdbuf_info = {
873 	NG_CMDSTRSIZ
874 };
875 const struct ng_parse_type ng_parse_cmdbuf_type = {
876 	&ng_parse_fixedstring_type,
877 	&ng_parse_cmdbuf_info
878 };
879 
880 /************************************************************************
881 			EXPLICITLY SIZED STRING TYPE
882  ************************************************************************/
883 
884 static int
885 ng_sizedstring_parse(const struct ng_parse_type *type,
886 	const char *s, int *off, const u_char *const start,
887 	u_char *const buf, int *buflen)
888 {
889 	char *sval;
890 	int len;
891 	int slen;
892 
893 	if ((sval = ng_get_string_token(s, off, &len, &slen)) == NULL)
894 		return (EINVAL);
895 	if (slen > USHRT_MAX) {
896 		free(sval, M_NETGRAPH_PARSE);
897 		return (EINVAL);
898 	}
899 	*off += len;
900 	*((u_int16_t *)buf) = (u_int16_t)slen;
901 	bcopy(sval, buf + 2, slen);
902 	free(sval, M_NETGRAPH_PARSE);
903 	*buflen = 2 + slen;
904 	return (0);
905 }
906 
907 static int
908 ng_sizedstring_unparse(const struct ng_parse_type *type,
909 	const u_char *data, int *off, char *cbuf, int cbuflen)
910 {
911 	const char *const raw = (const char *)data + *off + 2;
912 	const int slen = *((const u_int16_t *)(data + *off));
913 	char *const s = ng_encode_string(raw, slen);
914 	int error;
915 
916 	if (s == NULL)
917 		return (ENOMEM);
918 	if ((error = ng_parse_append(&cbuf, &cbuflen, "%s", s)) != 0) {
919 		free(s, M_NETGRAPH_PARSE);
920 		return (error);
921 	}
922 	free(s, M_NETGRAPH_PARSE);
923 	*off += slen + 2;
924 	return (0);
925 }
926 
927 static int
928 ng_sizedstring_getDefault(const struct ng_parse_type *type,
929 	const u_char *const start, u_char *buf, int *buflen)
930 {
931 	if (*buflen < 2)
932 		return (ERANGE);
933 	bzero(buf, 2);
934 	*buflen = 2;
935 	return (0);
936 }
937 
938 const struct ng_parse_type ng_parse_sizedstring_type = {
939 	NULL,
940 	NULL,
941 	NULL,
942 	ng_sizedstring_parse,
943 	ng_sizedstring_unparse,
944 	ng_sizedstring_getDefault,
945 	NULL
946 };
947 
948 /************************************************************************
949 			IP ADDRESS TYPE
950  ************************************************************************/
951 
952 static int
953 ng_ipaddr_parse(const struct ng_parse_type *type,
954 	const char *s, int *off, const u_char *const start,
955 	u_char *const buf, int *buflen)
956 {
957 	int i, error;
958 
959 	for (i = 0; i < 4; i++) {
960 		if ((error = ng_int8_parse(&ng_parse_int8_type,
961 		    s, off, start, buf + i, buflen)) != 0)
962 			return (error);
963 		if (i < 3) {
964 			if (s[*off] != '.')
965 				return (EINVAL);
966 			(*off)++;
967 		}
968 	}
969 	*buflen = 4;
970 	return (0);
971 }
972 
973 static int
974 ng_ipaddr_unparse(const struct ng_parse_type *type,
975 	const u_char *data, int *off, char *cbuf, int cbuflen)
976 {
977 	struct in_addr ip;
978 	int error;
979 
980 	bcopy(data + *off, &ip, sizeof(ip));
981 	if ((error = ng_parse_append(&cbuf, &cbuflen, "%d.%d.%d.%d",
982 	    ((u_char *)&ip)[0], ((u_char *)&ip)[1],
983 	    ((u_char *)&ip)[2], ((u_char *)&ip)[3])) != 0)
984 		return (error);
985 	*off += sizeof(ip);
986 	return (0);
987 }
988 
989 static int
990 ng_ipaddr_getDefault(const struct ng_parse_type *type,
991 	const u_char *const start, u_char *buf, int *buflen)
992 {
993 	struct in_addr ip = { 0 };
994 
995 	if (*buflen < sizeof(ip))
996 		return (ERANGE);
997 	bcopy(&ip, buf, sizeof(ip));
998 	*buflen = sizeof(ip);
999 	return (0);
1000 }
1001 
1002 const struct ng_parse_type ng_parse_ipaddr_type = {
1003 	NULL,
1004 	NULL,
1005 	NULL,
1006 	ng_ipaddr_parse,
1007 	ng_ipaddr_unparse,
1008 	ng_ipaddr_getDefault,
1009 	ng_int32_getAlign
1010 };
1011 
1012 /************************************************************************
1013 			ETHERNET ADDRESS TYPE
1014  ************************************************************************/
1015 
1016 static int
1017 ng_enaddr_parse(const struct ng_parse_type *type,
1018 	const char *s, int *const off, const u_char *const start,
1019 	u_char *const buf, int *const buflen)
1020 {
1021 	char *eptr;
1022 	u_long val;
1023 	int i;
1024 
1025 	if (*buflen < ETHER_ADDR_LEN)
1026 		return (ERANGE);
1027 	for (i = 0; i < ETHER_ADDR_LEN; i++) {
1028 		val = strtoul(s + *off, &eptr, 16);
1029 		if (val > 0xff || eptr == s + *off)
1030 			return (EINVAL);
1031 		buf[i] = (u_char)val;
1032 		*off = (eptr - s);
1033 		if (i < ETHER_ADDR_LEN - 1) {
1034 			if (*eptr != ':')
1035 				return (EINVAL);
1036 			(*off)++;
1037 		}
1038 	}
1039 	*buflen = ETHER_ADDR_LEN;
1040 	return (0);
1041 }
1042 
1043 static int
1044 ng_enaddr_unparse(const struct ng_parse_type *type,
1045 	const u_char *data, int *off, char *cbuf, int cbuflen)
1046 {
1047 	int len;
1048 
1049 	len = snprintf(cbuf, cbuflen, "%02x:%02x:%02x:%02x:%02x:%02x",
1050 	    data[*off], data[*off + 1], data[*off + 2],
1051 	    data[*off + 3], data[*off + 4], data[*off + 5]);
1052 	if (len >= cbuflen)
1053 		return (ERANGE);
1054 	*off += ETHER_ADDR_LEN;
1055 	return (0);
1056 }
1057 
1058 const struct ng_parse_type ng_parse_enaddr_type = {
1059 	NULL,
1060 	NULL,
1061 	NULL,
1062 	ng_enaddr_parse,
1063 	ng_enaddr_unparse,
1064 	NULL,
1065 	0
1066 };
1067 
1068 /************************************************************************
1069 			BYTE ARRAY TYPE
1070  ************************************************************************/
1071 
1072 /* Get the length of a byte array */
1073 static int
1074 ng_parse_bytearray_subtype_getLength(const struct ng_parse_type *type,
1075 	const u_char *start, const u_char *buf)
1076 {
1077 	ng_parse_array_getLength_t *const getLength = type->private;
1078 
1079 	return (*getLength)(type, start, buf);
1080 }
1081 
1082 /* Byte array element type is hex int8 */
1083 static const struct ng_parse_array_info ng_parse_bytearray_subtype_info = {
1084 	&ng_parse_hint8_type,
1085 	&ng_parse_bytearray_subtype_getLength,
1086 	NULL
1087 };
1088 static const struct ng_parse_type ng_parse_bytearray_subtype = {
1089 	&ng_parse_array_type,
1090 	&ng_parse_bytearray_subtype_info
1091 };
1092 
1093 static int
1094 ng_bytearray_parse(const struct ng_parse_type *type,
1095 	const char *s, int *off, const u_char *const start,
1096 	u_char *const buf, int *buflen)
1097 {
1098 	char *str;
1099 	int toklen;
1100 	int slen;
1101 
1102 	/* We accept either an array of bytes or a string constant */
1103 	if ((str = ng_get_string_token(s, off, &toklen, &slen)) != NULL) {
1104 		ng_parse_array_getLength_t *const getLength = type->info;
1105 		int arraylen;
1106 
1107 		arraylen = (*getLength)(type, start, buf);
1108 		if (arraylen > *buflen) {
1109 			free(str, M_NETGRAPH_PARSE);
1110 			return (ERANGE);
1111 		}
1112 		if (slen > arraylen) {
1113 			free(str, M_NETGRAPH_PARSE);
1114 			return (E2BIG);
1115 		}
1116 		bcopy(str, buf, slen);
1117 		bzero(buf + slen, arraylen - slen);
1118 		free(str, M_NETGRAPH_PARSE);
1119 		*off += toklen;
1120 		*buflen = arraylen;
1121 		return (0);
1122 	} else {
1123 		struct ng_parse_type subtype;
1124 
1125 		subtype = ng_parse_bytearray_subtype;
1126 		subtype.private = __DECONST(void *, type->info);
1127 		return ng_array_parse(&subtype, s, off, start, buf, buflen);
1128 	}
1129 }
1130 
1131 static int
1132 ng_bytearray_unparse(const struct ng_parse_type *type,
1133 	const u_char *data, int *off, char *cbuf, int cbuflen)
1134 {
1135 	struct ng_parse_type subtype;
1136 
1137 	subtype = ng_parse_bytearray_subtype;
1138 	subtype.private = __DECONST(void *, type->info);
1139 	return ng_array_unparse(&subtype, data, off, cbuf, cbuflen);
1140 }
1141 
1142 static int
1143 ng_bytearray_getDefault(const struct ng_parse_type *type,
1144 	const u_char *const start, u_char *buf, int *buflen)
1145 {
1146 	struct ng_parse_type subtype;
1147 
1148 	subtype = ng_parse_bytearray_subtype;
1149 	subtype.private = __DECONST(void *, type->info);
1150 	return ng_array_getDefault(&subtype, start, buf, buflen);
1151 }
1152 
1153 const struct ng_parse_type ng_parse_bytearray_type = {
1154 	NULL,
1155 	NULL,
1156 	NULL,
1157 	ng_bytearray_parse,
1158 	ng_bytearray_unparse,
1159 	ng_bytearray_getDefault,
1160 	NULL
1161 };
1162 
1163 /************************************************************************
1164 			STRUCT NG_MESG TYPE
1165  ************************************************************************/
1166 
1167 /* Get msg->header.arglen when "buf" is pointing to msg->data */
1168 static int
1169 ng_parse_ng_mesg_getLength(const struct ng_parse_type *type,
1170 	const u_char *start, const u_char *buf)
1171 {
1172 	const struct ng_mesg *msg;
1173 
1174 	msg = (const struct ng_mesg *)(buf - sizeof(*msg));
1175 	return msg->header.arglen;
1176 }
1177 
1178 /* Type for the variable length data portion of a struct ng_mesg */
1179 static const struct ng_parse_type ng_msg_data_type = {
1180 	&ng_parse_bytearray_type,
1181 	&ng_parse_ng_mesg_getLength
1182 };
1183 
1184 /* Type for the entire struct ng_mesg header with data section */
1185 static const struct ng_parse_struct_field ng_parse_ng_mesg_type_fields[]
1186 	= NG_GENERIC_NG_MESG_INFO(&ng_msg_data_type);
1187 const struct ng_parse_type ng_parse_ng_mesg_type = {
1188 	&ng_parse_struct_type,
1189 	&ng_parse_ng_mesg_type_fields,
1190 };
1191 
1192 /************************************************************************
1193 			COMPOSITE HELPER ROUTINES
1194  ************************************************************************/
1195 
1196 /*
1197  * Convert a structure or array from ASCII to binary
1198  */
1199 static int
1200 ng_parse_composite(const struct ng_parse_type *type, const char *s,
1201 	int *off, const u_char *const start, u_char *const buf, int *buflen,
1202 	const enum comptype ctype)
1203 {
1204 	const int num = ng_get_composite_len(type, start, buf, ctype);
1205 	int nextIndex = 0;		/* next implicit array index */
1206 	u_int index;			/* field or element index */
1207 	int *foff;			/* field value offsets in string */
1208 	int align, len, blen, error = 0;
1209 
1210 	/* Initialize */
1211 	foff = malloc(num * sizeof(*foff), M_NETGRAPH_PARSE, M_NOWAIT | M_ZERO);
1212 	if (foff == NULL) {
1213 		error = ENOMEM;
1214 		goto done;
1215 	}
1216 
1217 	/* Get opening brace/bracket */
1218 	if (ng_parse_get_token(s, off, &len)
1219 	    != (ctype == CT_STRUCT ? T_LBRACE : T_LBRACKET)) {
1220 		error = EINVAL;
1221 		goto done;
1222 	}
1223 	*off += len;
1224 
1225 	/* Get individual element value positions in the string */
1226 	for (;;) {
1227 		enum ng_parse_token tok;
1228 
1229 		/* Check for closing brace/bracket */
1230 		tok = ng_parse_get_token(s, off, &len);
1231 		if (tok == (ctype == CT_STRUCT ? T_RBRACE : T_RBRACKET)) {
1232 			*off += len;
1233 			break;
1234 		}
1235 
1236 		/* For arrays, the 'name' (ie, index) is optional, so
1237 		   distinguish name from values by seeing if the next
1238 		   token is an equals sign */
1239 		if (ctype != CT_STRUCT) {
1240 			u_long ul;
1241 			int len2, off2;
1242 			char *eptr;
1243 
1244 			/* If an opening brace/bracket, index is implied */
1245 			if (tok == T_LBRACE || tok == T_LBRACKET) {
1246 				index = nextIndex++;
1247 				goto gotIndex;
1248 			}
1249 
1250 			/* Might be an index, might be a value, either way... */
1251 			if (tok != T_WORD) {
1252 				error = EINVAL;
1253 				goto done;
1254 			}
1255 
1256 			/* If no equals sign follows, index is implied */
1257 			off2 = *off + len;
1258 			if (ng_parse_get_token(s, &off2, &len2) != T_EQUALS) {
1259 				index = nextIndex++;
1260 				goto gotIndex;
1261 			}
1262 
1263 			/* Index was specified explicitly; parse it */
1264 			ul = strtoul(s + *off, &eptr, 0);
1265 			if (ul == ULONG_MAX || eptr - (s + *off) != len) {
1266 				error = EINVAL;
1267 				goto done;
1268 			}
1269 			index = (u_int)ul;
1270 			nextIndex = index + 1;
1271 			*off += len + len2;
1272 		} else {			/* a structure field */
1273 			const struct ng_parse_struct_field *const
1274 			    fields = type->info;
1275 
1276 			/* Find the field by name (required) in field list */
1277 			if (tok != T_WORD) {
1278 				error = EINVAL;
1279 				goto done;
1280 			}
1281 			for (index = 0; index < num; index++) {
1282 				const struct ng_parse_struct_field *const
1283 				    field = &fields[index];
1284 
1285 				if (strncmp(&s[*off], field->name, len) == 0
1286 				    && field->name[len] == '\0')
1287 					break;
1288 			}
1289 			if (index == num) {
1290 				error = ENOENT;
1291 				goto done;
1292 			}
1293 			*off += len;
1294 
1295 			/* Get equals sign */
1296 			if (ng_parse_get_token(s, off, &len) != T_EQUALS) {
1297 				error = EINVAL;
1298 				goto done;
1299 			}
1300 			*off += len;
1301 		}
1302 gotIndex:
1303 
1304 		/* Check array index */
1305 		if (index >= num) {
1306 			error = E2BIG;
1307 			goto done;
1308 		}
1309 
1310 		/* Save value's position and skip over it for now */
1311 		if (foff[index] != 0) {
1312 			error = EALREADY;		/* duplicate */
1313 			goto done;
1314 		}
1315 		while (isspace(s[*off]))
1316 			(*off)++;
1317 		foff[index] = *off;
1318 		if ((error = ng_parse_skip_value(s, *off, &len)) != 0)
1319 			goto done;
1320 		*off += len;
1321 	}
1322 
1323 	/* Now build binary structure from supplied values and defaults */
1324 	for (blen = index = 0; index < num; index++) {
1325 		const struct ng_parse_type *const
1326 		    etype = ng_get_composite_etype(type, index, ctype);
1327 		int k, pad, vlen;
1328 
1329 		/* Zero-pad any alignment bytes */
1330 		pad = ng_parse_get_elem_pad(type, index, ctype, blen);
1331 		for (k = 0; k < pad; k++) {
1332 			if (blen >= *buflen) {
1333 				error = ERANGE;
1334 				goto done;
1335 			}
1336 			buf[blen++] = 0;
1337 		}
1338 
1339 		/* Get value */
1340 		vlen = *buflen - blen;
1341 		if (foff[index] == 0) {		/* use default value */
1342 			error = ng_get_composite_elem_default(type, index,
1343 			    start, buf + blen, &vlen, ctype);
1344 		} else {			/* parse given value */
1345 			*off = foff[index];
1346 			error = INVOKE(etype, parse)(etype,
1347 			    s, off, start, buf + blen, &vlen);
1348 		}
1349 		if (error != 0)
1350 			goto done;
1351 		blen += vlen;
1352 	}
1353 
1354 	/* Make total composite structure size a multiple of its alignment */
1355 	if ((align = ALIGNMENT(type)) != 0) {
1356 		while (blen % align != 0) {
1357 			if (blen >= *buflen) {
1358 				error = ERANGE;
1359 				goto done;
1360 			}
1361 			buf[blen++] = 0;
1362 		}
1363 	}
1364 
1365 	/* Done */
1366 	*buflen = blen;
1367 done:
1368 	if (foff != NULL)
1369 		free(foff, M_NETGRAPH_PARSE);
1370 	return (error);
1371 }
1372 
1373 /*
1374  * Convert an array or structure from binary to ASCII
1375  */
1376 static int
1377 ng_unparse_composite(const struct ng_parse_type *type, const u_char *data,
1378 	int *off, char *cbuf, int cbuflen, const enum comptype ctype)
1379 {
1380 	const struct ng_mesg *const hdr
1381 	    = (const struct ng_mesg *)(data - sizeof(*hdr));
1382 	const int num = ng_get_composite_len(type, data, data + *off, ctype);
1383 	const int workSize = 20 * 1024;		/* XXX hard coded constant */
1384 	int nextIndex = 0, didOne = 0;
1385 	int error, index;
1386 	u_char *workBuf;
1387 
1388 	/* Get workspace for checking default values */
1389 	workBuf = malloc(workSize, M_NETGRAPH_PARSE, M_NOWAIT);
1390 	if (workBuf == NULL)
1391 		return (ENOMEM);
1392 
1393 	/* Opening brace/bracket */
1394 	if ((error = ng_parse_append(&cbuf, &cbuflen, "%c",
1395 	    (ctype == CT_STRUCT) ? '{' : '[')) != 0)
1396 		goto fail;
1397 
1398 	/* Do each item */
1399 	for (index = 0; index < num; index++) {
1400 		const struct ng_parse_type *const
1401 		    etype = ng_get_composite_etype(type, index, ctype);
1402 
1403 		/* Skip any alignment pad bytes */
1404 		*off += ng_parse_get_elem_pad(type, index, ctype, *off);
1405 
1406 		/*
1407 		 * See if element is equal to its default value; skip if so.
1408 		 * Copy struct ng_mesg header for types that peek into it.
1409 		 */
1410 		if (sizeof(*hdr) + *off < workSize) {
1411 			int tempsize = workSize - sizeof(*hdr) - *off;
1412 
1413 			bcopy(hdr, workBuf, sizeof(*hdr) + *off);
1414 			if (ng_get_composite_elem_default(type, index, workBuf
1415 			      + sizeof(*hdr), workBuf + sizeof(*hdr) + *off,
1416 			      &tempsize, ctype) == 0
1417 			    && bcmp(workBuf + sizeof(*hdr) + *off,
1418 			      data + *off, tempsize) == 0) {
1419 				*off += tempsize;
1420 				continue;
1421 			}
1422 		}
1423 
1424 		/* Print name= */
1425 		if ((error = ng_parse_append(&cbuf, &cbuflen, " ")) != 0)
1426 			goto fail;
1427 		if (ctype != CT_STRUCT) {
1428 			if (index != nextIndex) {
1429 				nextIndex = index;
1430 				if ((error = ng_parse_append(&cbuf,
1431 				    &cbuflen, "%d=", index)) != 0)
1432 					goto fail;
1433 			}
1434 			nextIndex++;
1435 		} else {
1436 			const struct ng_parse_struct_field *const
1437 			    fields = type->info;
1438 
1439 			if ((error = ng_parse_append(&cbuf,
1440 			    &cbuflen, "%s=", fields[index].name)) != 0)
1441 				goto fail;
1442 		}
1443 
1444 		/* Print value */
1445 		if ((error = INVOKE(etype, unparse)
1446 		    (etype, data, off, cbuf, cbuflen)) != 0) {
1447 			free(workBuf, M_NETGRAPH_PARSE);
1448 			return (error);
1449 		}
1450 		cbuflen -= strlen(cbuf);
1451 		cbuf += strlen(cbuf);
1452 		didOne = 1;
1453 	}
1454 
1455 	/* Closing brace/bracket */
1456 	error = ng_parse_append(&cbuf, &cbuflen, "%s%c",
1457 	    didOne ? " " : "", (ctype == CT_STRUCT) ? '}' : ']');
1458 
1459 fail:
1460 	/* Clean up after failure */
1461 	free(workBuf, M_NETGRAPH_PARSE);
1462 	return (error);
1463 }
1464 
1465 /*
1466  * Generate the default value for an element of an array or structure
1467  * Returns EOPNOTSUPP if default value is unspecified.
1468  */
1469 static int
1470 ng_get_composite_elem_default(const struct ng_parse_type *type,
1471 	int index, const u_char *const start, u_char *buf, int *buflen,
1472 	const enum comptype ctype)
1473 {
1474 	const struct ng_parse_type *etype;
1475 	ng_getDefault_t *func;
1476 
1477 	switch (ctype) {
1478 	case CT_STRUCT:
1479 		break;
1480 	case CT_ARRAY:
1481 	    {
1482 		const struct ng_parse_array_info *const ai = type->info;
1483 
1484 		if (ai->getDefault != NULL) {
1485 			return (*ai->getDefault)(type,
1486 			    index, start, buf, buflen);
1487 		}
1488 		break;
1489 	    }
1490 	case CT_FIXEDARRAY:
1491 	    {
1492 		const struct ng_parse_fixedarray_info *const fi = type->info;
1493 
1494 		if (*fi->getDefault != NULL) {
1495 			return (*fi->getDefault)(type,
1496 			    index, start, buf, buflen);
1497 		}
1498 		break;
1499 	    }
1500 	default:
1501 	    panic("%s", __func__);
1502 	}
1503 
1504 	/* Default to element type default */
1505 	etype = ng_get_composite_etype(type, index, ctype);
1506 	func = METHOD(etype, getDefault);
1507 	if (func == NULL)
1508 		return (EOPNOTSUPP);
1509 	return (*func)(etype, start, buf, buflen);
1510 }
1511 
1512 /*
1513  * Get the number of elements in a struct, variable or fixed array.
1514  */
1515 static int
1516 ng_get_composite_len(const struct ng_parse_type *type,
1517 	const u_char *const start, const u_char *buf,
1518 	const enum comptype ctype)
1519 {
1520 	switch (ctype) {
1521 	case CT_STRUCT:
1522 	    {
1523 		const struct ng_parse_struct_field *const fields = type->info;
1524 		int numFields = 0;
1525 
1526 		for (numFields = 0; ; numFields++) {
1527 			const struct ng_parse_struct_field *const
1528 				fi = &fields[numFields];
1529 
1530 			if (fi->name == NULL)
1531 				break;
1532 		}
1533 		return (numFields);
1534 	    }
1535 	case CT_ARRAY:
1536 	    {
1537 		const struct ng_parse_array_info *const ai = type->info;
1538 
1539 		return (*ai->getLength)(type, start, buf);
1540 	    }
1541 	case CT_FIXEDARRAY:
1542 	    {
1543 		const struct ng_parse_fixedarray_info *const fi = type->info;
1544 
1545 		return fi->length;
1546 	    }
1547 	default:
1548 	    panic("%s", __func__);
1549 	}
1550 	return (0);
1551 }
1552 
1553 /*
1554  * Return the type of the index'th element of a composite structure
1555  */
1556 static const struct ng_parse_type *
1557 ng_get_composite_etype(const struct ng_parse_type *type,
1558 	int index, const enum comptype ctype)
1559 {
1560 	const struct ng_parse_type *etype = NULL;
1561 
1562 	switch (ctype) {
1563 	case CT_STRUCT:
1564 	    {
1565 		const struct ng_parse_struct_field *const fields = type->info;
1566 
1567 		etype = fields[index].type;
1568 		break;
1569 	    }
1570 	case CT_ARRAY:
1571 	    {
1572 		const struct ng_parse_array_info *const ai = type->info;
1573 
1574 		etype = ai->elementType;
1575 		break;
1576 	    }
1577 	case CT_FIXEDARRAY:
1578 	    {
1579 		const struct ng_parse_fixedarray_info *const fi = type->info;
1580 
1581 		etype = fi->elementType;
1582 		break;
1583 	    }
1584 	default:
1585 	    panic("%s", __func__);
1586 	}
1587 	return (etype);
1588 }
1589 
1590 /*
1591  * Get the number of bytes to skip to align for the next
1592  * element in a composite structure.
1593  */
1594 static int
1595 ng_parse_get_elem_pad(const struct ng_parse_type *type,
1596 	int index, enum comptype ctype, int posn)
1597 {
1598 	const struct ng_parse_type *const
1599 	    etype = ng_get_composite_etype(type, index, ctype);
1600 	int align;
1601 
1602 	/* Get element's alignment, and possibly override */
1603 	align = ALIGNMENT(etype);
1604 	if (ctype == CT_STRUCT) {
1605 		const struct ng_parse_struct_field *const fields = type->info;
1606 
1607 		if (fields[index].alignment != 0)
1608 			align = fields[index].alignment;
1609 	}
1610 
1611 	/* Return number of bytes to skip to align */
1612 	return (align ? (align - (posn % align)) % align : 0);
1613 }
1614 
1615 /************************************************************************
1616 			PARSING HELPER ROUTINES
1617  ************************************************************************/
1618 
1619 /*
1620  * Append to a fixed length string buffer.
1621  */
1622 static int
1623 ng_parse_append(char **cbufp, int *cbuflenp, const char *fmt, ...)
1624 {
1625 	va_list args;
1626 	int len;
1627 
1628 	va_start(args, fmt);
1629 	len = vsnprintf(*cbufp, *cbuflenp, fmt, args);
1630 	va_end(args);
1631 	if (len >= *cbuflenp)
1632 		return ERANGE;
1633 	*cbufp += len;
1634 	*cbuflenp -= len;
1635 
1636 	return (0);
1637 }
1638 
1639 /*
1640  * Skip over a value
1641  */
1642 static int
1643 ng_parse_skip_value(const char *s, int off0, int *lenp)
1644 {
1645 	int len, nbracket, nbrace;
1646 	int off = off0;
1647 
1648 	len = nbracket = nbrace = 0;
1649 	do {
1650 		switch (ng_parse_get_token(s, &off, &len)) {
1651 		case T_LBRACKET:
1652 			nbracket++;
1653 			break;
1654 		case T_LBRACE:
1655 			nbrace++;
1656 			break;
1657 		case T_RBRACKET:
1658 			if (nbracket-- == 0)
1659 				return (EINVAL);
1660 			break;
1661 		case T_RBRACE:
1662 			if (nbrace-- == 0)
1663 				return (EINVAL);
1664 			break;
1665 		case T_EOF:
1666 			return (EINVAL);
1667 		default:
1668 			break;
1669 		}
1670 		off += len;
1671 	} while (nbracket > 0 || nbrace > 0);
1672 	*lenp = off - off0;
1673 	return (0);
1674 }
1675 
1676 /*
1677  * Find the next token in the string, starting at offset *startp.
1678  * Returns the token type, with *startp pointing to the first char
1679  * and *lenp the length.
1680  */
1681 enum ng_parse_token
1682 ng_parse_get_token(const char *s, int *startp, int *lenp)
1683 {
1684 	char *t;
1685 	int i;
1686 
1687 	while (isspace(s[*startp]))
1688 		(*startp)++;
1689 	switch (s[*startp]) {
1690 	case '\0':
1691 		*lenp = 0;
1692 		return T_EOF;
1693 	case '{':
1694 		*lenp = 1;
1695 		return T_LBRACE;
1696 	case '}':
1697 		*lenp = 1;
1698 		return T_RBRACE;
1699 	case '[':
1700 		*lenp = 1;
1701 		return T_LBRACKET;
1702 	case ']':
1703 		*lenp = 1;
1704 		return T_RBRACKET;
1705 	case '=':
1706 		*lenp = 1;
1707 		return T_EQUALS;
1708 	case '"':
1709 		if ((t = ng_get_string_token(s, startp, lenp, NULL)) == NULL)
1710 			return T_ERROR;
1711 		free(t, M_NETGRAPH_PARSE);
1712 		return T_STRING;
1713 	default:
1714 		for (i = *startp + 1; s[i] != '\0' && !isspace(s[i])
1715 		    && s[i] != '{' && s[i] != '}' && s[i] != '['
1716 		    && s[i] != ']' && s[i] != '=' && s[i] != '"'; i++)
1717 			;
1718 		*lenp = i - *startp;
1719 		return T_WORD;
1720 	}
1721 }
1722 
1723 /*
1724  * Get a string token, which must be enclosed in double quotes.
1725  * The normal C backslash escapes are recognized.
1726  */
1727 char *
1728 ng_get_string_token(const char *s, int *startp, int *lenp, int *slenp)
1729 {
1730 	char *cbuf, *p;
1731 	int start, off;
1732 	int slen;
1733 
1734 	while (isspace(s[*startp]))
1735 		(*startp)++;
1736 	start = *startp;
1737 	if (s[*startp] != '"')
1738 		return (NULL);
1739 	cbuf = malloc(strlen(s + start), M_NETGRAPH_PARSE, M_NOWAIT);
1740 	if (cbuf == NULL)
1741 		return (NULL);
1742 	strcpy(cbuf, s + start + 1);
1743 	for (slen = 0, off = 1, p = cbuf; *p != '\0'; slen++, off++, p++) {
1744 		if (*p == '"') {
1745 			*p = '\0';
1746 			*lenp = off + 1;
1747 			if (slenp != NULL)
1748 				*slenp = slen;
1749 			return (cbuf);
1750 		} else if (p[0] == '\\' && p[1] != '\0') {
1751 			int x, k;
1752 			char *v;
1753 
1754 			strcpy(p, p + 1);
1755 			v = p;
1756 			switch (*p) {
1757 			case 't':
1758 				*v = '\t';
1759 				off++;
1760 				continue;
1761 			case 'n':
1762 				*v = '\n';
1763 				off++;
1764 				continue;
1765 			case 'r':
1766 				*v = '\r';
1767 				off++;
1768 				continue;
1769 			case 'v':
1770 				*v =  '\v';
1771 				off++;
1772 				continue;
1773 			case 'f':
1774 				*v =  '\f';
1775 				off++;
1776 				continue;
1777 			case '"':
1778 				*v =  '"';
1779 				off++;
1780 				continue;
1781 			case '0': case '1': case '2': case '3':
1782 			case '4': case '5': case '6': case '7':
1783 				for (x = k = 0;
1784 				    k < 3 && *v >= '0' && *v <= '7'; v++) {
1785 					x = (x << 3) + (*v - '0');
1786 					off++;
1787 				}
1788 				*--v = (char)x;
1789 				break;
1790 			case 'x':
1791 				for (v++, x = k = 0;
1792 				    k < 2 && isxdigit(*v); v++) {
1793 					x = (x << 4) + (isdigit(*v) ?
1794 					      (*v - '0') :
1795 					      (tolower(*v) - 'a' + 10));
1796 					off++;
1797 				}
1798 				*--v = (char)x;
1799 				break;
1800 			default:
1801 				continue;
1802 			}
1803 			strcpy(p, v);
1804 		}
1805 	}
1806 	free(cbuf, M_NETGRAPH_PARSE);
1807 	return (NULL);		/* no closing quote */
1808 }
1809 
1810 /*
1811  * Encode a string so it can be safely put in double quotes.
1812  * Caller must free the result. Exactly "slen" characters
1813  * are encoded.
1814  */
1815 char *
1816 ng_encode_string(const char *raw, int slen)
1817 {
1818 	char *cbuf;
1819 	int off = 0;
1820 	int i;
1821 
1822 	cbuf = malloc(strlen(raw) * 4 + 3, M_NETGRAPH_PARSE, M_NOWAIT);
1823 	if (cbuf == NULL)
1824 		return (NULL);
1825 	cbuf[off++] = '"';
1826 	for (i = 0; i < slen; i++, raw++) {
1827 		switch (*raw) {
1828 		case '\t':
1829 			cbuf[off++] = '\\';
1830 			cbuf[off++] = 't';
1831 			break;
1832 		case '\f':
1833 			cbuf[off++] = '\\';
1834 			cbuf[off++] = 'f';
1835 			break;
1836 		case '\n':
1837 			cbuf[off++] = '\\';
1838 			cbuf[off++] = 'n';
1839 			break;
1840 		case '\r':
1841 			cbuf[off++] = '\\';
1842 			cbuf[off++] = 'r';
1843 			break;
1844 		case '\v':
1845 			cbuf[off++] = '\\';
1846 			cbuf[off++] = 'v';
1847 			break;
1848 		case '"':
1849 		case '\\':
1850 			cbuf[off++] = '\\';
1851 			cbuf[off++] = *raw;
1852 			break;
1853 		default:
1854 			if (*raw < 0x20 || *raw > 0x7e) {
1855 				off += sprintf(cbuf + off,
1856 				    "\\x%02x", (u_char)*raw);
1857 				break;
1858 			}
1859 			cbuf[off++] = *raw;
1860 			break;
1861 		}
1862 	}
1863 	cbuf[off++] = '"';
1864 	cbuf[off] = '\0';
1865 	return (cbuf);
1866 }
1867 
1868 /************************************************************************
1869 			VIRTUAL METHOD LOOKUP
1870  ************************************************************************/
1871 
1872 static ng_parse_t *
1873 ng_get_parse_method(const struct ng_parse_type *t)
1874 {
1875 	while (t != NULL && t->parse == NULL)
1876 		t = t->supertype;
1877 	return (t ? t->parse : NULL);
1878 }
1879 
1880 static ng_unparse_t *
1881 ng_get_unparse_method(const struct ng_parse_type *t)
1882 {
1883 	while (t != NULL && t->unparse == NULL)
1884 		t = t->supertype;
1885 	return (t ? t->unparse : NULL);
1886 }
1887 
1888 static ng_getDefault_t *
1889 ng_get_getDefault_method(const struct ng_parse_type *t)
1890 {
1891 	while (t != NULL && t->getDefault == NULL)
1892 		t = t->supertype;
1893 	return (t ? t->getDefault : NULL);
1894 }
1895 
1896 static ng_getAlign_t *
1897 ng_get_getAlign_method(const struct ng_parse_type *t)
1898 {
1899 	while (t != NULL && t->getAlign == NULL)
1900 		t = t->supertype;
1901 	return (t ? t->getAlign : NULL);
1902 }
1903