xref: /netbsd-src/common/lib/libprop/prop_data.c (revision d48f14661dda8638fee055ba15d35bdfb29b9fa8)
1 /*	$NetBSD: prop_data.c,v 1.2 2006/05/18 03:05:19 thorpej Exp $	*/
2 
3 /*-
4  * Copyright (c) 2006 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Jason R. Thorpe.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *      This product includes software developed by the NetBSD
21  *      Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 #include <prop/prop_data.h>
40 #include "prop_object_impl.h"
41 
42 #if defined(_KERNEL)
43 #include <sys/systm.h>
44 #elif defined(_STANDALONE)
45 #include <sys/param.h>
46 #include <lib/libkern/libkern.h>
47 #else
48 #include <errno.h>
49 #include <limits.h>
50 #include <stdlib.h>
51 #endif
52 
53 struct _prop_data {
54 	struct _prop_object	pd_obj;
55 	union {
56 		void *		pdu_mutable;
57 		const void *	pdu_immutable;
58 	} pd_un;
59 #define	pd_mutable		pd_un.pdu_mutable
60 #define	pd_immutable		pd_un.pdu_immutable
61 	size_t			pd_size;
62 	int			pd_flags;
63 };
64 
65 #define	PD_F_NOCOPY		0x01
66 
67 _PROP_POOL_INIT(_prop_data_pool, sizeof(struct _prop_data), "propdata")
68 
69 _PROP_MALLOC_DEFINE(M_PROP_DATA, "prop data",
70 		    "property data container object")
71 
72 static void		_prop_data_free(void *);
73 static boolean_t	_prop_data_externalize(
74 				struct _prop_object_externalize_context *,
75 				void *);
76 static boolean_t	_prop_data_equals(void *, void *);
77 
78 static const struct _prop_object_type _prop_object_type_data = {
79 	.pot_type	=	PROP_TYPE_DATA,
80 	.pot_free	=	_prop_data_free,
81 	.pot_extern	=	_prop_data_externalize,
82 	.pot_equals	=	_prop_data_equals,
83 };
84 
85 #define	prop_object_is_data(x)		\
86 	((x)->pd_obj.po_type == &_prop_object_type_data)
87 
88 static void
89 _prop_data_free(void *v)
90 {
91 	prop_data_t pd = v;
92 
93 	if ((pd->pd_flags & PD_F_NOCOPY) == 0 && pd->pd_mutable != NULL)
94 	    	_PROP_FREE(pd->pd_mutable, M_PROP_DATA);
95 	_PROP_POOL_PUT(_prop_data_pool, v);
96 }
97 
98 static const char _prop_data_base64[] =
99     "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
100 static const char _prop_data_pad64 = '=';
101 
102 static boolean_t
103 _prop_data_externalize(struct _prop_object_externalize_context *ctx, void *v)
104 {
105 	prop_data_t pd = v;
106 	size_t i, srclen;
107 	const uint8_t *src;
108 	uint8_t output[4];
109 	uint8_t input[3];
110 
111 	if (pd->pd_size == 0)
112 		return (_prop_object_externalize_empty_tag(ctx, "data"));
113 
114 	if (_prop_object_externalize_start_tag(ctx, "data") == FALSE)
115 		return (FALSE);
116 
117 	for (src = pd->pd_immutable, srclen = pd->pd_size;
118 	     srclen > 2; srclen -= 3) {
119 		input[0] = *src++;
120 		input[1] = *src++;
121 		input[2] = *src++;
122 
123 		output[0] = (uint32_t)input[0] >> 2;
124 		output[1] = ((uint32_t)(input[0] & 0x03) << 4) +
125 		    ((uint32_t)input[1] >> 4);
126 		output[2] = ((u_int32_t)(input[1] & 0x0f) << 2) +
127 		    ((uint32_t)input[2] >> 6);
128 		output[3] = input[2] & 0x3f;
129 		_PROP_ASSERT(output[0] < 64);
130 		_PROP_ASSERT(output[1] < 64);
131 		_PROP_ASSERT(output[2] < 64);
132 		_PROP_ASSERT(output[3] < 64);
133 
134 		if (_prop_object_externalize_append_char(ctx,
135 				_prop_data_base64[output[0]]) == FALSE ||
136 		    _prop_object_externalize_append_char(ctx,
137 		    		_prop_data_base64[output[1]]) == FALSE ||
138 		    _prop_object_externalize_append_char(ctx,
139 		    		_prop_data_base64[output[2]]) == FALSE ||
140 		    _prop_object_externalize_append_char(ctx,
141 		    		_prop_data_base64[output[3]]) == FALSE)
142 			return (FALSE);
143 	}
144 
145 	if (srclen != 0) {
146 		input[0] = input[1] = input[2] = '\0';
147 		for (i = 0; i < srclen; i++)
148 			input[i] = *src++;
149 
150 		output[0] = (uint32_t)input[0] >> 2;
151 		output[1] = ((uint32_t)(input[0] & 0x03) << 4) +
152 		    ((uint32_t)input[1] >> 4);
153 		output[2] = ((u_int32_t)(input[1] & 0x0f) << 2) +
154 		    ((uint32_t)input[2] >> 6);
155 		_PROP_ASSERT(output[0] < 64);
156 		_PROP_ASSERT(output[1] < 64);
157 		_PROP_ASSERT(output[2] < 64);
158 
159 		if (_prop_object_externalize_append_char(ctx,
160 				_prop_data_base64[output[0]]) == FALSE ||
161 		    _prop_object_externalize_append_char(ctx,
162 		    		_prop_data_base64[output[1]]) == FALSE ||
163 		    _prop_object_externalize_append_char(ctx,
164 		    		srclen == 1 ? _prop_data_pad64
165 				: _prop_data_base64[output[2]]) == FALSE ||
166 		    _prop_object_externalize_append_char(ctx,
167 		    		_prop_data_pad64) == FALSE)
168 			return (FALSE);
169 	}
170 
171 	if (_prop_object_externalize_end_tag(ctx, "data") == FALSE)
172 		return (FALSE);
173 
174 	return (TRUE);
175 }
176 
177 static boolean_t
178 _prop_data_equals(void *v1, void *v2)
179 {
180 	prop_data_t pd1 = v1;
181 	prop_data_t pd2 = v2;
182 
183 	_PROP_ASSERT(prop_object_is_data(pd1));
184 	_PROP_ASSERT(prop_object_is_data(pd2));
185 	if (pd1 == pd2)
186 		return (TRUE);
187 	if (pd1->pd_size != pd2->pd_size)
188 		return (FALSE);
189 	if (pd1->pd_size == 0) {
190 		_PROP_ASSERT(pd1->pd_immutable == NULL);
191 		_PROP_ASSERT(pd2->pd_immutable == NULL);
192 		return (TRUE);
193 	}
194 	return (memcmp(pd1->pd_immutable, pd2->pd_immutable,
195 		       pd1->pd_size) == 0);
196 }
197 
198 static prop_data_t
199 _prop_data_alloc(void)
200 {
201 	prop_data_t pd;
202 
203 	pd = _PROP_POOL_GET(_prop_data_pool);
204 	if (pd != NULL) {
205 		_prop_object_init(&pd->pd_obj, &_prop_object_type_data);
206 
207 		pd->pd_mutable = NULL;
208 		pd->pd_size = 0;
209 		pd->pd_flags = 0;
210 	}
211 
212 	return (pd);
213 }
214 
215 /*
216  * prop_data_create_data --
217  *	Create a data container that contains a copy of the data.
218  */
219 prop_data_t
220 prop_data_create_data(const void *v, size_t size)
221 {
222 	prop_data_t pd;
223 	void *nv;
224 
225 	pd = _prop_data_alloc();
226 	if (pd != NULL) {
227 		nv = _PROP_MALLOC(size, M_PROP_DATA);
228 		if (nv == NULL) {
229 			_prop_data_free(pd);
230 			return (NULL);
231 		}
232 		memcpy(nv, v, size);
233 		pd->pd_mutable = nv;
234 		pd->pd_size = size;
235 	}
236 	return (pd);
237 }
238 
239 /*
240  * prop_data_create_data_nocopy --
241  *	Create an immutable data container that contains a refrence to the
242  *	provided external data.
243  */
244 prop_data_t
245 prop_data_create_data_nocopy(const void *v, size_t size)
246 {
247 	prop_data_t pd;
248 
249 	pd = _prop_data_alloc();
250 	if (pd != NULL) {
251 		pd->pd_immutable = v;
252 		pd->pd_size = size;
253 		pd->pd_flags |= PD_F_NOCOPY;
254 	}
255 	return (pd);
256 }
257 
258 /*
259  * prop_data_copy --
260  *	Copy a data container.  If the original data is external, then
261  *	the copy is also references the same external data.
262  */
263 prop_data_t
264 prop_data_copy(prop_data_t opd)
265 {
266 	prop_data_t pd;
267 
268 	_PROP_ASSERT(prop_object_is_data(opd));
269 
270 	pd = _prop_data_alloc();
271 	if (pd != NULL) {
272 		pd->pd_size = opd->pd_size;
273 		pd->pd_flags = opd->pd_flags;
274 		if (opd->pd_flags & PD_F_NOCOPY)
275 			pd->pd_immutable = opd->pd_immutable;
276 		else if (opd->pd_size != 0) {
277 			void *nv = _PROP_MALLOC(pd->pd_size, M_PROP_DATA);
278 			if (nv == NULL) {
279 				_prop_data_free(pd);
280 				return (NULL);
281 			}
282 			memcpy(nv, opd->pd_immutable, opd->pd_size);
283 			pd->pd_mutable = nv;
284 		}
285 	}
286 	return (pd);
287 }
288 
289 /*
290  * prop_data_size --
291  *	Return the size of the data.
292  */
293 size_t
294 prop_data_size(prop_data_t pd)
295 {
296 
297 	_PROP_ASSERT(prop_object_is_data(pd));
298 	return (pd->pd_size);
299 }
300 
301 /*
302  * prop_data_data --
303  *	Return a copy of the contents of the data container.
304  *	The data is allocated with the M_TEMP malloc type.
305  *	If the data container is empty, NULL is returned.
306  */
307 void *
308 prop_data_data(prop_data_t pd)
309 {
310 	void *v;
311 
312 	_PROP_ASSERT(prop_object_is_data(pd));
313 
314 	if (pd->pd_size == 0) {
315 		_PROP_ASSERT(pd->pd_immutable == NULL);
316 		return (NULL);
317 	}
318 
319 	_PROP_ASSERT(pd->pd_immutable != NULL);
320 
321 	v = _PROP_MALLOC(pd->pd_size, M_TEMP);
322 	if (v != NULL)
323 		memcpy(v, pd->pd_immutable, pd->pd_size);
324 
325 	return (v);
326 }
327 
328 /*
329  * prop_data_data_nocopy --
330  *	Return an immutable reference to the contents of the data
331  *	container.
332  */
333 const void *
334 prop_data_data_nocopy(prop_data_t pd)
335 {
336 
337 	_PROP_ASSERT(prop_object_is_data(pd));
338 	_PROP_ASSERT((pd->pd_size == 0 && pd->pd_immutable == NULL) ||
339 		     (pd->pd_size != 0 && pd->pd_immutable != NULL));
340 
341 	return (pd->pd_immutable);
342 }
343 
344 /*
345  * prop_data_equals --
346  *	Return TRUE if two strings are equivalent.
347  */
348 boolean_t
349 prop_data_equals(prop_data_t pd1, prop_data_t pd2)
350 {
351 
352 	return (_prop_data_equals(pd1, pd2));
353 }
354 
355 /*
356  * prop_data_equals_data --
357  *	Return TRUE if the contained data is equivalent to the specified
358  *	external data.
359  */
360 boolean_t
361 prop_data_equals_data(prop_data_t pd, const void *v, size_t size)
362 {
363 
364 	_PROP_ASSERT(prop_object_is_data(pd));
365 	if (pd->pd_size != size)
366 		return (FALSE);
367 	return (memcmp(pd->pd_immutable, v, size) == 0);
368 }
369 
370 static boolean_t
371 _prop_data_internalize_decode(struct _prop_object_internalize_context *ctx,
372 			     uint8_t *target, size_t targsize, size_t *sizep,
373 			     const char **cpp)
374 {
375 	const char *src;
376 	size_t tarindex;
377 	int state, ch;
378 	const char *pos;
379 
380 	state = 0;
381 	tarindex = 0;
382 	src = ctx->poic_cp;
383 
384 	for (;;) {
385 		ch = (unsigned char) *src++;
386 		if (_PROP_EOF(ch))
387 			return (FALSE);
388 		if (_PROP_ISSPACE(ch))
389 			continue;
390 		if (ch == '<') {
391 			src--;
392 			break;
393 		}
394 		if (ch == _prop_data_pad64)
395 			break;
396 
397 		pos = strchr(_prop_data_base64, ch);
398 		if (pos == NULL)
399 			return (FALSE);
400 
401 		switch (state) {
402 		case 0:
403 			if (target) {
404 				if (tarindex >= targsize)
405 					return (FALSE);
406 				target[tarindex] =
407 				    (pos - _prop_data_base64) << 2;
408 			}
409 			state = 1;
410 			break;
411 
412 		case 1:
413 			if (target) {
414 				if (tarindex + 1 >= targsize)
415 					return (FALSE);
416 				target[tarindex] |=
417 				    (uint32_t)(pos - _prop_data_base64) >> 4;
418 				target[tarindex + 1] =
419 				    ((pos - _prop_data_base64) & 0xf) << 4;
420 			}
421 			tarindex++;
422 			state = 2;
423 			break;
424 
425 		case 2:
426 			if (target) {
427 				if (tarindex + 1 >= targsize)
428 					return (FALSE);
429 				target[tarindex] |=
430 				    (uint32_t)(pos - _prop_data_base64) >> 2;
431 				target[tarindex + 1] =
432 				    ((pos - _prop_data_base64) & 0x3) << 6;
433 			}
434 			tarindex++;
435 			state = 3;
436 			break;
437 
438 		case 3:
439 			if (target) {
440 				if (tarindex >= targsize)
441 					return (FALSE);
442 				target[tarindex] |= (pos - _prop_data_base64);
443 			}
444 			tarindex++;
445 			state = 0;
446 			break;
447 
448 		default:
449 			_PROP_ASSERT(/*CONSTCOND*/0);
450 		}
451 	}
452 
453 	/*
454 	 * We are done decoding the Base64 characters.  Let's see if we
455 	 * ended up on a byte boundary and/or with unrecognized trailing
456 	 * characters.
457 	 */
458 	if (ch == _prop_data_pad64) {
459 		ch = (unsigned char) *src;	/* src already advanced */
460 		if (_PROP_EOF(ch))
461 			return (FALSE);
462 		switch (state) {
463 		case 0:		/* Invalid = in first position */
464 		case 1:		/* Invalid = in second position */
465 			return (FALSE);
466 
467 		case 2:		/* Valid, one byte of info */
468 			/* Skip whitespace */
469 			for (ch = (unsigned char) *src++;
470 			     ch != '<'; ch = (unsigned char) *src++) {
471 				if (_PROP_EOF(ch))
472 					return (FALSE);
473 				if (!_PROP_ISSPACE(ch))
474 					break;
475 			}
476 			/* Make sure there is another trailing = */
477 			if (ch != _prop_data_pad64)
478 				return (FALSE);
479 			ch = (unsigned char) *src;
480 			/* FALLTHROUGH */
481 
482 		case 3:		/* Valid, two bytes of info */
483 			/*
484 			 * We know this char is a =.  Is there anything but
485 			 * whitespace after it?
486 			 */
487 			for (; ch != '<'; ch = (unsigned char) *src++) {
488 				if (_PROP_EOF(ch))
489 					return (FALSE);
490 				if (!_PROP_ISSPACE(ch))
491 					return (FALSE);
492 			}
493 		}
494 	} else {
495 		/*
496 		 * We ended by seeing the end of the Base64 string.  Make
497 		 * sure there are no partial bytes lying around.
498 		 */
499 		if (state != 0)
500 			return (FALSE);
501 	}
502 
503 	_PROP_ASSERT(*src == '<');
504 	if (sizep != NULL)
505 		*sizep = tarindex;
506 	if (cpp != NULL)
507 		*cpp = src;
508 
509 	return (TRUE);
510 }
511 
512 /*
513  * _prop_data_internalize --
514  *	Parse a <data>...</data> and return the object created from the
515  *	external representation.
516  */
517 prop_object_t
518 _prop_data_internalize(struct _prop_object_internalize_context *ctx)
519 {
520 	prop_data_t data;
521 	uint8_t *buf;
522 	size_t len, alen;
523 
524 	/* We don't accept empty elements. */
525 	if (ctx->poic_is_empty_element)
526 		return (NULL);
527 
528 	/*
529 	 * If we got a "size" attribute, get the size of the data blob
530 	 * from that.  Otherwise, we have to figure it out from the base64.
531 	 */
532 	if (ctx->poic_tagattr != NULL) {
533 		char *cp;
534 
535 		if (!_PROP_TAGATTR_MATCH(ctx, "size") ||
536 		    ctx->poic_tagattrval_len == 0)
537 			return (NULL);
538 
539 #ifndef _KERNEL
540 		errno = 0;
541 #endif
542 		/* XXX Assumes size_t and unsigned long are the same size. */
543 		len = strtoul(ctx->poic_tagattrval, &cp, 0);
544 #ifndef _KERNEL		/* XXX can't check for ERANGE in the kernel */
545 		if (len == ULONG_MAX && errno == ERANGE)
546 			return (NULL);
547 #endif
548 		if (cp != ctx->poic_tagattrval + ctx->poic_tagattrval_len)
549 			return (NULL);
550 		_PROP_ASSERT(*cp == '\"');
551 	} else if (_prop_data_internalize_decode(ctx, NULL, 0, &len,
552 						NULL) == FALSE)
553 		return (NULL);
554 
555 	/*
556 	 * Always allocate one extra in case we don't land on an even byte
557 	 * boundary during the decode.
558 	 */
559 	buf = _PROP_MALLOC(len + 1, M_PROP_DATA);
560 	if (buf == NULL)
561 		return (NULL);
562 
563 	if (_prop_data_internalize_decode(ctx, buf, len + 1, &alen,
564 					  &ctx->poic_cp) == FALSE) {
565 		_PROP_FREE(buf, M_PROP_DATA);
566 		return (NULL);
567 	}
568 	if (alen != len) {
569 		_PROP_FREE(buf, M_PROP_DATA);
570 		return (NULL);
571 	}
572 
573 	if (_prop_object_internalize_find_tag(ctx, "data",
574 					      _PROP_TAG_TYPE_END) == FALSE) {
575 		_PROP_FREE(buf, M_PROP_DATA);
576 		return (NULL);
577 	}
578 
579 	data = _prop_data_alloc();
580 	if (data == NULL) {
581 		_PROP_FREE(buf, M_PROP_DATA);
582 		return (NULL);
583 	}
584 
585 	data->pd_mutable = buf;
586 	data->pd_size = len;
587 
588 	return (data);
589 }
590