tasn_enc.c@ 91772

Last change on this file since 91772 was 91772, checked in by vboxsync, 3 years ago
openssl-1.1.1l: Applied and adjusted our OpenSSL changes to 1.1.1l. bugref:10126
File size: 18.9 KB

Line
1	/*
2	* Copyright 2000-2020 The OpenSSL Project Authors. All Rights Reserved.
3	*
4	* Licensed under the OpenSSL license (the "License"). You may not use
5	* this file except in compliance with the License. You can obtain a copy
6	* in the file LICENSE in the source distribution or at
7	* https://www.openssl.org/source/license.html
8	*/
9
10	#include <stddef.h>
11	#include <string.h>
12	#include "internal/cryptlib.h"
13	#include <openssl/asn1.h>
14	#include <openssl/asn1t.h>
15	#include <openssl/objects.h>
16	#include "crypto/asn1.h"
17	#include "asn1_local.h"
18
19	static int asn1_i2d_ex_primitive(ASN1_VALUE pval, unsigned char out,
20	const ASN1_ITEM *it, int tag, int aclass);
21	static int asn1_set_seq_out(STACK_OF(ASN1_VALUE) sk, unsigned char *out,
22	int skcontlen, const ASN1_ITEM *item,
23	int do_sort, int iclass);
24	static int asn1_template_ex_i2d(ASN1_VALUE pval, unsigned char out,
25	const ASN1_TEMPLATE *tt, int tag, int aclass);
26	static int asn1_item_flags_i2d(ASN1_VALUE val, unsigned char *out,
27	const ASN1_ITEM *it, int flags);
28	static int asn1_ex_i2c(ASN1_VALUE *pval, unsigned char cout, int *putype,
29	const ASN1_ITEM *it);
30
31	/*
32	* Top level i2d equivalents: the 'ndef' variant instructs the encoder to use
33	* indefinite length constructed encoding, where appropriate
34	*/
35
36	int ASN1_item_ndef_i2d(ASN1_VALUE val, unsigned char *out,
37	const ASN1_ITEM *it)
38	{
39	return asn1_item_flags_i2d(val, out, it, ASN1_TFLG_NDEF);
40	}
41
42	int ASN1_item_i2d(ASN1_VALUE val, unsigned char out, const ASN1_ITEM it)
43	{
44	return asn1_item_flags_i2d(val, out, it, 0);
45	}
46
47	/*
48	* Encode an ASN1 item, this is use by the standard 'i2d' function. 'out'
49	* points to a buffer to output the data to. The new i2d has one additional
50	* feature. If the output buffer is NULL (i.e. *out == NULL) then a buffer is
51	* allocated and populated with the encoding.
52	*/
53
54	static int asn1_item_flags_i2d(ASN1_VALUE val, unsigned char *out,
55	const ASN1_ITEM *it, int flags)
56	{
57	if (out && !*out) {
58	unsigned char p, buf;
59	int len;
60
61	len = ASN1_item_ex_i2d(&val, NULL, it, -1, flags);
62	if (len <= 0)
63	return len;
64	if ((buf = OPENSSL_malloc(len)) == NULL) {
65	ASN1err(ASN1_F_ASN1_ITEM_FLAGS_I2D, ERR_R_MALLOC_FAILURE);
66	return -1;
67	}
68	p = buf;
69	ASN1_item_ex_i2d(&val, &p, it, -1, flags);
70	*out = buf;
71	return len;
72	}
73
74	return ASN1_item_ex_i2d(&val, out, it, -1, flags);
75	}
76
77	/*
78	* Encode an item, taking care of IMPLICIT tagging (if any). This function
79	* performs the normal item handling: it can be used in external types.
80	*/
81
82	int ASN1_item_ex_i2d(ASN1_VALUE pval, unsigned char out,
83	const ASN1_ITEM *it, int tag, int aclass)
84	{
85	const ASN1_TEMPLATE *tt = NULL;
86	int i, seqcontlen, seqlen, ndef = 1;
87	const ASN1_EXTERN_FUNCS *ef;
88	const ASN1_AUX *aux = it->funcs;
89	ASN1_aux_cb *asn1_cb = 0;
90
91	if ((it->itype != ASN1_ITYPE_PRIMITIVE) && !*pval)
92	return 0;
93
94	if (aux && aux->asn1_cb)
95	asn1_cb = aux->asn1_cb;
96
97	switch (it->itype) {
98
99	case ASN1_ITYPE_PRIMITIVE:
100	if (it->templates)
101	return asn1_template_ex_i2d(pval, out, it->templates,
102	tag, aclass);
103	return asn1_i2d_ex_primitive(pval, out, it, tag, aclass);
104
105	case ASN1_ITYPE_MSTRING:
106	/*
107	* It never makes sense for multi-strings to have implicit tagging, so
108	* if tag != -1, then this looks like an error in the template.
109	*/
110	if (tag != -1) {
111	ASN1err(ASN1_F_ASN1_ITEM_EX_I2D, ASN1_R_BAD_TEMPLATE);
112	return -1;
113	}
114	return asn1_i2d_ex_primitive(pval, out, it, -1, aclass);
115
116	case ASN1_ITYPE_CHOICE:
117	/*
118	* It never makes sense for CHOICE types to have implicit tagging, so
119	* if tag != -1, then this looks like an error in the template.
120	*/
121	if (tag != -1) {
122	ASN1err(ASN1_F_ASN1_ITEM_EX_I2D, ASN1_R_BAD_TEMPLATE);
123	return -1;
124	}
125	if (asn1_cb && !asn1_cb(ASN1_OP_I2D_PRE, pval, it, NULL))
126	return 0;
127	i = asn1_get_choice_selector(pval, it);
128	if ((i >= 0) && (i < it->tcount)) {
129	ASN1_VALUE **pchval;
130	const ASN1_TEMPLATE *chtt;
131	chtt = it->templates + i;
132	pchval = asn1_get_field_ptr(pval, chtt);
133	return asn1_template_ex_i2d(pchval, out, chtt, -1, aclass);
134	}
135	/* Fixme: error condition if selector out of range */
136	if (asn1_cb && !asn1_cb(ASN1_OP_I2D_POST, pval, it, NULL))
137	return 0;
138	break;
139
140	case ASN1_ITYPE_EXTERN:
141	/* If new style i2d it does all the work */
142	ef = it->funcs;
143	return ef->asn1_ex_i2d(pval, out, it, tag, aclass);
144
145	case ASN1_ITYPE_NDEF_SEQUENCE:
146	/* Use indefinite length constructed if requested */
147	if (aclass & ASN1_TFLG_NDEF)
148	ndef = 2;
149	/* fall through */
150
151	case ASN1_ITYPE_SEQUENCE:
152	i = asn1_enc_restore(&seqcontlen, out, pval, it);
153	/* An error occurred */
154	if (i < 0)
155	return 0;
156	/* We have a valid cached encoding... */
157	if (i > 0)
158	return seqcontlen;
159	/* Otherwise carry on */
160	seqcontlen = 0;
161	/* If no IMPLICIT tagging set to SEQUENCE, UNIVERSAL */
162	if (tag == -1) {
163	tag = V_ASN1_SEQUENCE;
164	/* Retain any other flags in aclass */
165	aclass = (aclass & ~ASN1_TFLG_TAG_CLASS)
166	\| V_ASN1_UNIVERSAL;
167	}
168	if (asn1_cb && !asn1_cb(ASN1_OP_I2D_PRE, pval, it, NULL))
169	return 0;
170	/* First work out sequence content length */
171	for (i = 0, tt = it->templates; i < it->tcount; tt++, i++) {
172	const ASN1_TEMPLATE *seqtt;
173	ASN1_VALUE **pseqval;
174	int tmplen;
175	seqtt = asn1_do_adb(pval, tt, 1);
176	if (!seqtt)
177	return 0;
178	pseqval = asn1_get_field_ptr(pval, seqtt);
179	tmplen = asn1_template_ex_i2d(pseqval, NULL, seqtt, -1, aclass);
180	if (tmplen == -1 \|\| (tmplen > INT_MAX - seqcontlen))
181	return -1;
182	seqcontlen += tmplen;
183	}
184
185	seqlen = ASN1_object_size(ndef, seqcontlen, tag);
186	if (!out \|\| seqlen == -1)
187	return seqlen;
188	/* Output SEQUENCE header */
189	ASN1_put_object(out, ndef, seqcontlen, tag, aclass);
190	for (i = 0, tt = it->templates; i < it->tcount; tt++, i++) {
191	const ASN1_TEMPLATE *seqtt;
192	ASN1_VALUE **pseqval;
193	seqtt = asn1_do_adb(pval, tt, 1);
194	if (!seqtt)
195	return 0;
196	pseqval = asn1_get_field_ptr(pval, seqtt);
197	/* FIXME: check for errors in enhanced version */
198	asn1_template_ex_i2d(pseqval, out, seqtt, -1, aclass);
199	}
200	if (ndef == 2)
201	ASN1_put_eoc(out);
202	if (asn1_cb && !asn1_cb(ASN1_OP_I2D_POST, pval, it, NULL))
203	return 0;
204	return seqlen;
205
206	default:
207	return 0;
208
209	}
210	return 0;
211	}
212
213	static int asn1_template_ex_i2d(ASN1_VALUE pval, unsigned char out,
214	const ASN1_TEMPLATE *tt, int tag, int iclass)
215	{
216	int i, ret, flags, ttag, tclass, ndef;
217	ASN1_VALUE *tval;
218	flags = tt->flags;
219
220	/*
221	* If field is embedded then val needs fixing so it is a pointer to
222	* a pointer to a field.
223	*/
224	if (flags & ASN1_TFLG_EMBED) {
225	tval = (ASN1_VALUE *)pval;
226	pval = &tval;
227	}
228	/*
229	* Work out tag and class to use: tagging may come either from the
230	* template or the arguments, not both because this would create
231	* ambiguity. Additionally the iclass argument may contain some
232	* additional flags which should be noted and passed down to other
233	* levels.
234	*/
235	if (flags & ASN1_TFLG_TAG_MASK) {
236	/* Error if argument and template tagging */
237	if (tag != -1)
238	/* FIXME: error code here */
239	return -1;
240	/* Get tagging from template */
241	ttag = tt->tag;
242	tclass = flags & ASN1_TFLG_TAG_CLASS;
243	} else if (tag != -1) {
244	/* No template tagging, get from arguments */
245	ttag = tag;
246	tclass = iclass & ASN1_TFLG_TAG_CLASS;
247	} else {
248	ttag = -1;
249	tclass = 0;
250	}
251	/*
252	* Remove any class mask from iflag.
253	*/
254	iclass &= ~ASN1_TFLG_TAG_CLASS;
255
256	/*
257	* At this point 'ttag' contains the outer tag to use, 'tclass' is the
258	* class and iclass is any flags passed to this function.
259	*/
260
261	/* if template and arguments require ndef, use it */
262	if ((flags & ASN1_TFLG_NDEF) && (iclass & ASN1_TFLG_NDEF))
263	ndef = 2;
264	else
265	ndef = 1;
266
267	if (flags & ASN1_TFLG_SK_MASK) {
268	/* SET OF, SEQUENCE OF */
269	STACK_OF(ASN1_VALUE) sk = (STACK_OF(ASN1_VALUE) )*pval;
270	int isset, sktag, skaclass;
271	int skcontlen, sklen;
272	ASN1_VALUE *skitem;
273
274	if (!*pval)
275	return 0;
276
277	if (flags & ASN1_TFLG_SET_OF) {
278	isset = 1;
279	/* 2 means we reorder */
280	if (flags & ASN1_TFLG_SEQUENCE_OF)
281	isset = 2;
282	} else
283	isset = 0;
284
285	/*
286	* Work out inner tag value: if EXPLICIT or no tagging use underlying
287	* type.
288	*/
289	if ((ttag != -1) && !(flags & ASN1_TFLG_EXPTAG)) {
290	sktag = ttag;
291	skaclass = tclass;
292	} else {
293	skaclass = V_ASN1_UNIVERSAL;
294	if (isset)
295	sktag = V_ASN1_SET;
296	else
297	sktag = V_ASN1_SEQUENCE;
298	}
299
300	/* Determine total length of items */
301	skcontlen = 0;
302	for (i = 0; i < sk_ASN1_VALUE_num(sk); i++) {
303	int tmplen;
304	skitem = sk_ASN1_VALUE_value(sk, i);
305	tmplen = ASN1_item_ex_i2d(&skitem, NULL, ASN1_ITEM_ptr(tt->item),
306	-1, iclass);
307	if (tmplen == -1 \|\| (skcontlen > INT_MAX - tmplen))
308	return -1;
309	skcontlen += tmplen;
310	}
311	sklen = ASN1_object_size(ndef, skcontlen, sktag);
312	if (sklen == -1)
313	return -1;
314	/* If EXPLICIT need length of surrounding tag */
315	if (flags & ASN1_TFLG_EXPTAG)
316	ret = ASN1_object_size(ndef, sklen, ttag);
317	else
318	ret = sklen;
319
320	if (!out \|\| ret == -1)
321	return ret;
322
323	/* Now encode this lot... */
324	/* EXPLICIT tag */
325	if (flags & ASN1_TFLG_EXPTAG)
326	ASN1_put_object(out, ndef, sklen, ttag, tclass);
327	/* SET or SEQUENCE and IMPLICIT tag */
328	ASN1_put_object(out, ndef, skcontlen, sktag, skaclass);
329	/* And the stuff itself */
330	asn1_set_seq_out(sk, out, skcontlen, ASN1_ITEM_ptr(tt->item),
331	isset, iclass);
332	if (ndef == 2) {
333	ASN1_put_eoc(out);
334	if (flags & ASN1_TFLG_EXPTAG)
335	ASN1_put_eoc(out);
336	}
337
338	return ret;
339	}
340
341	if (flags & ASN1_TFLG_EXPTAG) {
342	/* EXPLICIT tagging */
343	/* Find length of tagged item */
344	i = ASN1_item_ex_i2d(pval, NULL, ASN1_ITEM_ptr(tt->item), -1, iclass);
345	if (!i)
346	return 0;
347	/* Find length of EXPLICIT tag */
348	ret = ASN1_object_size(ndef, i, ttag);
349	if (out && ret != -1) {
350	/* Output tag and item */
351	ASN1_put_object(out, ndef, i, ttag, tclass);
352	ASN1_item_ex_i2d(pval, out, ASN1_ITEM_ptr(tt->item), -1, iclass);
353	if (ndef == 2)
354	ASN1_put_eoc(out);
355	}
356	return ret;
357	}
358
359	/* Either normal or IMPLICIT tagging: combine class and flags */
360	return ASN1_item_ex_i2d(pval, out, ASN1_ITEM_ptr(tt->item),
361	ttag, tclass \| iclass);
362
363	}
364
365	/* Temporary structure used to hold DER encoding of items for SET OF */
366
367	typedef struct {
368	unsigned char *data;
369	int length;
370	ASN1_VALUE *field;
371	} DER_ENC;
372
373	static int der_cmp(const void a, const void b)
374	{
375	const DER_ENC d1 = a, d2 = b;
376	int cmplen, i;
377	cmplen = (d1->length < d2->length) ? d1->length : d2->length;
378	i = memcmp(d1->data, d2->data, cmplen);
379	if (i)
380	return i;
381	return d1->length - d2->length;
382	}
383
384	/* Output the content octets of SET OF or SEQUENCE OF */
385
386	static int asn1_set_seq_out(STACK_OF(ASN1_VALUE) sk, unsigned char *out,
387	int skcontlen, const ASN1_ITEM *item,
388	int do_sort, int iclass)
389	{
390	int i;
391	ASN1_VALUE *skitem;
392	unsigned char tmpdat = NULL, p = NULL;
393	DER_ENC derlst = NULL, tder;
394	if (do_sort) {
395	/* Don't need to sort less than 2 items */
396	if (sk_ASN1_VALUE_num(sk) < 2)
397	do_sort = 0;
398	else {
399	derlst = OPENSSL_malloc(sk_ASN1_VALUE_num(sk)
400	* sizeof(*derlst));
401	if (derlst == NULL)
402	return 0;
403	tmpdat = OPENSSL_malloc(skcontlen);
404	if (tmpdat == NULL) {
405	OPENSSL_free(derlst);
406	return 0;
407	}
408	}
409	}
410	/* If not sorting just output each item */
411	if (!do_sort) {
412	for (i = 0; i < sk_ASN1_VALUE_num(sk); i++) {
413	skitem = sk_ASN1_VALUE_value(sk, i);
414	ASN1_item_ex_i2d(&skitem, out, item, -1, iclass);
415	}
416	return 1;
417	}
418	p = tmpdat;
419
420	/* Doing sort: build up a list of each member's DER encoding */
421	for (i = 0, tder = derlst; i < sk_ASN1_VALUE_num(sk); i++, tder++) {
422	skitem = sk_ASN1_VALUE_value(sk, i);
423	tder->data = p;
424	tder->length = ASN1_item_ex_i2d(&skitem, &p, item, -1, iclass);
425	tder->field = skitem;
426	}
427
428	/* Now sort them */
429	qsort(derlst, sk_ASN1_VALUE_num(sk), sizeof(*derlst), der_cmp);
430	/* Output sorted DER encoding */
431	p = *out;
432	for (i = 0, tder = derlst; i < sk_ASN1_VALUE_num(sk); i++, tder++) {
433	memcpy(p, tder->data, tder->length);
434	p += tder->length;
435	}
436	*out = p;
437	/* If do_sort is 2 then reorder the STACK */
438	if (do_sort == 2) {
439	for (i = 0, tder = derlst; i < sk_ASN1_VALUE_num(sk); i++, tder++)
440	(void)sk_ASN1_VALUE_set(sk, i, tder->field);
441	}
442	OPENSSL_free(derlst);
443	OPENSSL_free(tmpdat);
444	return 1;
445	}
446
447	static int asn1_i2d_ex_primitive(ASN1_VALUE pval, unsigned char out,
448	const ASN1_ITEM *it, int tag, int aclass)
449	{
450	int len;
451	int utype;
452	int usetag;
453	int ndef = 0;
454
455	utype = it->utype;
456
457	/*
458	* Get length of content octets and maybe find out the underlying type.
459	*/
460
461	len = asn1_ex_i2c(pval, NULL, &utype, it);
462
463	/*
464	* If SEQUENCE, SET or OTHER then header is included in pseudo content
465	* octets so don't include tag+length. We need to check here because the
466	* call to asn1_ex_i2c() could change utype.
467	*/
468	if ((utype == V_ASN1_SEQUENCE) \|\| (utype == V_ASN1_SET) \|\|
469	(utype == V_ASN1_OTHER))
470	usetag = 0;
471	else
472	usetag = 1;
473
474	/* -1 means omit type */
475
476	if (len == -1)
477	return 0;
478
479	/* -2 return is special meaning use ndef */
480	if (len == -2) {
481	ndef = 2;
482	len = 0;
483	}
484
485	/* If not implicitly tagged get tag from underlying type */
486	if (tag == -1)
487	tag = utype;
488
489	/* Output tag+length followed by content octets */
490	if (out) {
491	if (usetag)
492	ASN1_put_object(out, ndef, len, tag, aclass);
493	asn1_ex_i2c(pval, *out, &utype, it);
494	if (ndef)
495	ASN1_put_eoc(out);
496	else
497	*out += len;
498	}
499
500	if (usetag)
501	return ASN1_object_size(ndef, len, tag);
502	return len;
503	}
504
505	/* Produce content octets from a structure */
506
507	static int asn1_ex_i2c(ASN1_VALUE *pval, unsigned char cout, int *putype,
508	const ASN1_ITEM *it)
509	{
510	ASN1_BOOLEAN *tbool = NULL;
511	ASN1_STRING *strtmp;
512	ASN1_OBJECT *otmp;
513	int utype;
514	const unsigned char *cont;
515	unsigned char c;
516	int len;
517	const ASN1_PRIMITIVE_FUNCS *pf;
518	pf = it->funcs;
519	if (pf && pf->prim_i2c)
520	return pf->prim_i2c(pval, cout, putype, it);
521
522	/* Should type be omitted? */
523	if ((it->itype != ASN1_ITYPE_PRIMITIVE)
524	\|\| (it->utype != V_ASN1_BOOLEAN)) {
525	if (!*pval)
526	return -1;
527	}
528
529	if (it->itype == ASN1_ITYPE_MSTRING) {
530	/* If MSTRING type set the underlying type */
531	strtmp = (ASN1_STRING )pval;
532	utype = strtmp->type;
533	*putype = utype;
534	} else if (it->utype == V_ASN1_ANY) {
535	/* If ANY set type and pointer to value */
536	ASN1_TYPE *typ;
537	typ = (ASN1_TYPE )pval;
538	utype = typ->type;
539	*putype = utype;
540	pval = &typ->value.asn1_value;
541	} else
542	utype = *putype;
543
544	switch (utype) {
545	case V_ASN1_OBJECT:
546	otmp = (ASN1_OBJECT )pval;
547	cont = otmp->data;
548	len = otmp->length;
549	if (cont == NULL \|\| len == 0)
550	return -1;
551	break;
552
553	case V_ASN1_NULL:
554	cont = NULL;
555	len = 0;
556	break;
557
558	case V_ASN1_BOOLEAN:
559	tbool = (ASN1_BOOLEAN *)pval;
560	if (*tbool == -1)
561	return -1;
562	if (it->utype != V_ASN1_ANY) {
563	/*
564	* Default handling if value == size field then omit
565	*/
566	if (*tbool && (it->size > 0))
567	return -1;
568	if (!*tbool && !it->size)
569	return -1;
570	}
571	c = (unsigned char)*tbool;
572	cont = &c;
573	len = 1;
574	break;
575
576	case V_ASN1_BIT_STRING:
577	return i2c_ASN1_BIT_STRING((ASN1_BIT_STRING )pval,
578	cout ? &cout : NULL);
579
580	case V_ASN1_INTEGER:
581	case V_ASN1_ENUMERATED:
582	/*
583	* These are all have the same content format as ASN1_INTEGER
584	*/
585	return i2c_ASN1_INTEGER((ASN1_INTEGER )pval, cout ? &cout : NULL);
586
587	case V_ASN1_OCTET_STRING:
588	case V_ASN1_NUMERICSTRING:
589	case V_ASN1_PRINTABLESTRING:
590	case V_ASN1_T61STRING:
591	case V_ASN1_VIDEOTEXSTRING:
592	case V_ASN1_IA5STRING:
593	case V_ASN1_UTCTIME:
594	case V_ASN1_GENERALIZEDTIME:
595	case V_ASN1_GRAPHICSTRING:
596	case V_ASN1_VISIBLESTRING:
597	case V_ASN1_GENERALSTRING:
598	case V_ASN1_UNIVERSALSTRING:
599	case V_ASN1_BMPSTRING:
600	case V_ASN1_UTF8STRING:
601	case V_ASN1_SEQUENCE:
602	case V_ASN1_SET:
603	default:
604	/* All based on ASN1_STRING and handled the same */
605	strtmp = (ASN1_STRING )pval;
606	/* Special handling for NDEF */
607	if ((it->size == ASN1_TFLG_NDEF)
608	&& (strtmp->flags & ASN1_STRING_FLAG_NDEF)) {
609	if (cout) {
610	strtmp->data = cout;
611	strtmp->length = 0;
612	}
613	/* Special return code */
614	return -2;
615	}
616	cont = strtmp->data;
617	len = strtmp->length;
618
619	break;
620
621	}
622	if (cout && len)
623	memcpy(cout, cont, len);
624	return len;
625	}

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source: vbox/trunk/src/libs/openssl-1.1.1l/crypto/asn1/tasn_enc.c@ 91772

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