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      1 /* Copyright (C) 1995-1998 Eric Young (eay (at) cryptsoft.com)
      2  * All rights reserved.
      3  *
      4  * This package is an SSL implementation written
      5  * by Eric Young (eay (at) cryptsoft.com).
      6  * The implementation was written so as to conform with Netscapes SSL.
      7  *
      8  * This library is free for commercial and non-commercial use as long as
      9  * the following conditions are aheared to.  The following conditions
     10  * apply to all code found in this distribution, be it the RC4, RSA,
     11  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
     12  * included with this distribution is covered by the same copyright terms
     13  * except that the holder is Tim Hudson (tjh (at) cryptsoft.com).
     14  *
     15  * Copyright remains Eric Young's, and as such any Copyright notices in
     16  * the code are not to be removed.
     17  * If this package is used in a product, Eric Young should be given attribution
     18  * as the author of the parts of the library used.
     19  * This can be in the form of a textual message at program startup or
     20  * in documentation (online or textual) provided with the package.
     21  *
     22  * Redistribution and use in source and binary forms, with or without
     23  * modification, are permitted provided that the following conditions
     24  * are met:
     25  * 1. Redistributions of source code must retain the copyright
     26  *    notice, this list of conditions and the following disclaimer.
     27  * 2. Redistributions in binary form must reproduce the above copyright
     28  *    notice, this list of conditions and the following disclaimer in the
     29  *    documentation and/or other materials provided with the distribution.
     30  * 3. All advertising materials mentioning features or use of this software
     31  *    must display the following acknowledgement:
     32  *    "This product includes cryptographic software written by
     33  *     Eric Young (eay (at) cryptsoft.com)"
     34  *    The word 'cryptographic' can be left out if the rouines from the library
     35  *    being used are not cryptographic related :-).
     36  * 4. If you include any Windows specific code (or a derivative thereof) from
     37  *    the apps directory (application code) you must include an acknowledgement:
     38  *    "This product includes software written by Tim Hudson (tjh (at) cryptsoft.com)"
     39  *
     40  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
     41  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     43  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
     44  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     45  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     46  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     48  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     49  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     50  * SUCH DAMAGE.
     51  *
     52  * The licence and distribution terms for any publically available version or
     53  * derivative of this code cannot be changed.  i.e. this code cannot simply be
     54  * copied and put under another distribution licence
     55  * [including the GNU Public Licence.] */
     56 
     57 #include <openssl/asn1.h>
     58 
     59 #include <string.h>
     60 
     61 #include <openssl/asn1t.h>
     62 #include <openssl/mem.h>
     63 
     64 
     65 static int asn1_i2d_ex_primitive(ASN1_VALUE **pval, unsigned char **out,
     66 					const ASN1_ITEM *it,
     67 					int tag, int aclass);
     68 static int asn1_set_seq_out(STACK_OF(ASN1_VALUE) *sk, unsigned char **out,
     69 					int skcontlen, const ASN1_ITEM *item,
     70 					int do_sort, int iclass);
     71 static int asn1_template_ex_i2d(ASN1_VALUE **pval, unsigned char **out,
     72 					const ASN1_TEMPLATE *tt,
     73 					int tag, int aclass);
     74 static int asn1_item_flags_i2d(ASN1_VALUE *val, unsigned char **out,
     75 					const ASN1_ITEM *it, int flags);
     76 
     77 /* Top level i2d equivalents: the 'ndef' variant instructs the encoder
     78  * to use indefinite length constructed encoding, where appropriate
     79  */
     80 
     81 int ASN1_item_ndef_i2d(ASN1_VALUE *val, unsigned char **out,
     82 						const ASN1_ITEM *it)
     83 	{
     84 	return asn1_item_flags_i2d(val, out, it, ASN1_TFLG_NDEF);
     85 	}
     86 
     87 int ASN1_item_i2d(ASN1_VALUE *val, unsigned char **out, const ASN1_ITEM *it)
     88 	{
     89 	return asn1_item_flags_i2d(val, out, it, 0);
     90 	}
     91 
     92 /* Encode an ASN1 item, this is use by the
     93  * standard 'i2d' function. 'out' points to
     94  * a buffer to output the data to.
     95  *
     96  * The new i2d has one additional feature. If the output
     97  * buffer is NULL (i.e. *out == NULL) then a buffer is
     98  * allocated and populated with the encoding.
     99  */
    100 
    101 static int asn1_item_flags_i2d(ASN1_VALUE *val, unsigned char **out,
    102 					const ASN1_ITEM *it, int flags)
    103 	{
    104 	if (out && !*out)
    105 		{
    106 		unsigned char *p, *buf;
    107 		int len;
    108 		len = ASN1_item_ex_i2d(&val, NULL, it, -1, flags);
    109 		if (len <= 0)
    110 			return len;
    111 		buf = OPENSSL_malloc(len);
    112 		if (!buf)
    113 			return -1;
    114 		p = buf;
    115 		ASN1_item_ex_i2d(&val, &p, it, -1, flags);
    116 		*out = buf;
    117 		return len;
    118 		}
    119 
    120 	return ASN1_item_ex_i2d(&val, out, it, -1, flags);
    121 	}
    122 
    123 /* Encode an item, taking care of IMPLICIT tagging (if any).
    124  * This function performs the normal item handling: it can be
    125  * used in external types.
    126  */
    127 
    128 int ASN1_item_ex_i2d(ASN1_VALUE **pval, unsigned char **out,
    129 			const ASN1_ITEM *it, int tag, int aclass)
    130 	{
    131 	const ASN1_TEMPLATE *tt = NULL;
    132 	unsigned char *p = NULL;
    133 	int i, seqcontlen, seqlen, ndef = 1;
    134 	const ASN1_COMPAT_FUNCS *cf;
    135 	const ASN1_EXTERN_FUNCS *ef;
    136 	const ASN1_AUX *aux = it->funcs;
    137 	ASN1_aux_cb *asn1_cb = 0;
    138 
    139 	if ((it->itype != ASN1_ITYPE_PRIMITIVE) && !*pval)
    140 		return 0;
    141 
    142 	if (aux && aux->asn1_cb)
    143 		 asn1_cb = aux->asn1_cb;
    144 
    145 	switch(it->itype)
    146 		{
    147 
    148 		case ASN1_ITYPE_PRIMITIVE:
    149 		if (it->templates)
    150 			return asn1_template_ex_i2d(pval, out, it->templates,
    151 								tag, aclass);
    152 		return asn1_i2d_ex_primitive(pval, out, it, tag, aclass);
    153 		break;
    154 
    155 		case ASN1_ITYPE_MSTRING:
    156 		return asn1_i2d_ex_primitive(pval, out, it, -1, aclass);
    157 
    158 		case ASN1_ITYPE_CHOICE:
    159 		if (asn1_cb && !asn1_cb(ASN1_OP_I2D_PRE, pval, it, NULL))
    160 				return 0;
    161 		i = asn1_get_choice_selector(pval, it);
    162 		if ((i >= 0) && (i < it->tcount))
    163 			{
    164 			ASN1_VALUE **pchval;
    165 			const ASN1_TEMPLATE *chtt;
    166 			chtt = it->templates + i;
    167 			pchval = asn1_get_field_ptr(pval, chtt);
    168 			return asn1_template_ex_i2d(pchval, out, chtt,
    169 								-1, aclass);
    170 			}
    171 		/* Fixme: error condition if selector out of range */
    172 		if (asn1_cb && !asn1_cb(ASN1_OP_I2D_POST, pval, it, NULL))
    173 				return 0;
    174 		break;
    175 
    176 		case ASN1_ITYPE_EXTERN:
    177 		/* If new style i2d it does all the work */
    178 		ef = it->funcs;
    179 		return ef->asn1_ex_i2d(pval, out, it, tag, aclass);
    180 
    181 		case ASN1_ITYPE_COMPAT:
    182 		/* old style hackery... */
    183 		cf = it->funcs;
    184 		if (out)
    185 			p = *out;
    186 		i = cf->asn1_i2d(*pval, out);
    187 		/* Fixup for IMPLICIT tag: note this messes up for tags > 30,
    188 		 * but so did the old code. Tags > 30 are very rare anyway.
    189 		 */
    190 		if (out && (tag != -1))
    191 			*p = aclass | tag | (*p & V_ASN1_CONSTRUCTED);
    192 		return i;
    193 
    194 		case ASN1_ITYPE_NDEF_SEQUENCE:
    195 		/* Use indefinite length constructed if requested */
    196 		if (aclass & ASN1_TFLG_NDEF) ndef = 2;
    197 		/* fall through */
    198 
    199 		case ASN1_ITYPE_SEQUENCE:
    200 		i = asn1_enc_restore(&seqcontlen, out, pval, it);
    201 		/* An error occurred */
    202 		if (i < 0)
    203 			return 0;
    204 		/* We have a valid cached encoding... */
    205 		if (i > 0)
    206 			return seqcontlen;
    207 		/* Otherwise carry on */
    208 		seqcontlen = 0;
    209 		/* If no IMPLICIT tagging set to SEQUENCE, UNIVERSAL */
    210 		if (tag == -1)
    211 			{
    212 			tag = V_ASN1_SEQUENCE;
    213 			/* Retain any other flags in aclass */
    214 			aclass = (aclass & ~ASN1_TFLG_TAG_CLASS)
    215 					| V_ASN1_UNIVERSAL;
    216 			}
    217 		if (asn1_cb && !asn1_cb(ASN1_OP_I2D_PRE, pval, it, NULL))
    218 				return 0;
    219 		/* First work out sequence content length */
    220 		for (i = 0, tt = it->templates; i < it->tcount; tt++, i++)
    221 			{
    222 			const ASN1_TEMPLATE *seqtt;
    223 			ASN1_VALUE **pseqval;
    224 			seqtt = asn1_do_adb(pval, tt, 1);
    225 			if (!seqtt)
    226 				return 0;
    227 			pseqval = asn1_get_field_ptr(pval, seqtt);
    228 			/* FIXME: check for errors in enhanced version */
    229 			seqcontlen += asn1_template_ex_i2d(pseqval, NULL, seqtt,
    230 								-1, aclass);
    231 			}
    232 
    233 		seqlen = ASN1_object_size(ndef, seqcontlen, tag);
    234 		if (!out)
    235 			return seqlen;
    236 		/* Output SEQUENCE header */
    237 		ASN1_put_object(out, ndef, seqcontlen, tag, aclass);
    238 		for (i = 0, tt = it->templates; i < it->tcount; tt++, i++)
    239 			{
    240 			const ASN1_TEMPLATE *seqtt;
    241 			ASN1_VALUE **pseqval;
    242 			seqtt = asn1_do_adb(pval, tt, 1);
    243 			if (!seqtt)
    244 				return 0;
    245 			pseqval = asn1_get_field_ptr(pval, seqtt);
    246 			/* FIXME: check for errors in enhanced version */
    247 			asn1_template_ex_i2d(pseqval, out, seqtt, -1, aclass);
    248 			}
    249 		if (ndef == 2)
    250 			ASN1_put_eoc(out);
    251 		if (asn1_cb && !asn1_cb(ASN1_OP_I2D_POST, pval, it, NULL))
    252 				return 0;
    253 		return seqlen;
    254 
    255 		default:
    256 		return 0;
    257 
    258 		}
    259 	return 0;
    260 	}
    261 
    262 int ASN1_template_i2d(ASN1_VALUE **pval, unsigned char **out,
    263 							const ASN1_TEMPLATE *tt)
    264 	{
    265 	return asn1_template_ex_i2d(pval, out, tt, -1, 0);
    266 	}
    267 
    268 static int asn1_template_ex_i2d(ASN1_VALUE **pval, unsigned char **out,
    269 				const ASN1_TEMPLATE *tt, int tag, int iclass)
    270 	{
    271 	int i, ret, flags, ttag, tclass, ndef;
    272 	size_t j;
    273 	flags = tt->flags;
    274 	/* Work out tag and class to use: tagging may come
    275 	 * either from the template or the arguments, not both
    276 	 * because this would create ambiguity. Additionally
    277 	 * the iclass argument may contain some additional flags
    278 	 * which should be noted and passed down to other levels.
    279 	 */
    280 	if (flags & ASN1_TFLG_TAG_MASK)
    281 		{
    282 		/* Error if argument and template tagging */
    283 		if (tag != -1)
    284 			/* FIXME: error code here */
    285 			return -1;
    286 		/* Get tagging from template */
    287 		ttag = tt->tag;
    288 		tclass = flags & ASN1_TFLG_TAG_CLASS;
    289 		}
    290 	else if (tag != -1)
    291 		{
    292 		/* No template tagging, get from arguments */
    293 		ttag = tag;
    294 		tclass = iclass & ASN1_TFLG_TAG_CLASS;
    295 		}
    296 	else
    297 		{
    298 		ttag = -1;
    299 		tclass = 0;
    300 		}
    301 	/*
    302 	 * Remove any class mask from iflag.
    303 	 */
    304 	iclass &= ~ASN1_TFLG_TAG_CLASS;
    305 
    306 	/* At this point 'ttag' contains the outer tag to use,
    307 	 * 'tclass' is the class and iclass is any flags passed
    308 	 * to this function.
    309 	 */
    310 
    311 	/* if template and arguments require ndef, use it */
    312 	if ((flags & ASN1_TFLG_NDEF) && (iclass & ASN1_TFLG_NDEF))
    313 		ndef = 2;
    314 	else ndef = 1;
    315 
    316 	if (flags & ASN1_TFLG_SK_MASK)
    317 		{
    318 		/* SET OF, SEQUENCE OF */
    319 		STACK_OF(ASN1_VALUE) *sk = (STACK_OF(ASN1_VALUE) *)*pval;
    320 		int isset, sktag, skaclass;
    321 		int skcontlen, sklen;
    322 		ASN1_VALUE *skitem;
    323 
    324 		if (!*pval)
    325 			return 0;
    326 
    327 		if (flags & ASN1_TFLG_SET_OF)
    328 			{
    329 			isset = 1;
    330 			/* 2 means we reorder */
    331 			if (flags & ASN1_TFLG_SEQUENCE_OF)
    332 				isset = 2;
    333 			}
    334 		else isset = 0;
    335 
    336 		/* Work out inner tag value: if EXPLICIT
    337 		 * or no tagging use underlying type.
    338 		 */
    339 		if ((ttag != -1) && !(flags & ASN1_TFLG_EXPTAG))
    340 			{
    341 			sktag = ttag;
    342 			skaclass = tclass;
    343 			}
    344 		else
    345 			{
    346 			skaclass = V_ASN1_UNIVERSAL;
    347 			if (isset)
    348 				sktag = V_ASN1_SET;
    349 			else sktag = V_ASN1_SEQUENCE;
    350 			}
    351 
    352 		/* Determine total length of items */
    353 		skcontlen = 0;
    354 		for (j = 0; j < sk_ASN1_VALUE_num(sk); j++)
    355 			{
    356 			skitem = sk_ASN1_VALUE_value(sk, j);
    357 			skcontlen += ASN1_item_ex_i2d(&skitem, NULL,
    358 						ASN1_ITEM_ptr(tt->item),
    359 							-1, iclass);
    360 			}
    361 		sklen = ASN1_object_size(ndef, skcontlen, sktag);
    362 		/* If EXPLICIT need length of surrounding tag */
    363 		if (flags & ASN1_TFLG_EXPTAG)
    364 			ret = ASN1_object_size(ndef, sklen, ttag);
    365 		else ret = sklen;
    366 
    367 		if (!out)
    368 			return ret;
    369 
    370 		/* Now encode this lot... */
    371 		/* EXPLICIT tag */
    372 		if (flags & ASN1_TFLG_EXPTAG)
    373 			ASN1_put_object(out, ndef, sklen, ttag, tclass);
    374 		/* SET or SEQUENCE and IMPLICIT tag */
    375 		ASN1_put_object(out, ndef, skcontlen, sktag, skaclass);
    376 		/* And the stuff itself */
    377 		asn1_set_seq_out(sk, out, skcontlen, ASN1_ITEM_ptr(tt->item),
    378 								isset, iclass);
    379 		if (ndef == 2)
    380 			{
    381 			ASN1_put_eoc(out);
    382 			if (flags & ASN1_TFLG_EXPTAG)
    383 				ASN1_put_eoc(out);
    384 			}
    385 
    386 		return ret;
    387 		}
    388 
    389 	if (flags & ASN1_TFLG_EXPTAG)
    390 		{
    391 		/* EXPLICIT tagging */
    392 		/* Find length of tagged item */
    393 		i = ASN1_item_ex_i2d(pval, NULL, ASN1_ITEM_ptr(tt->item),
    394 								-1, iclass);
    395 		if (!i)
    396 			return 0;
    397 		/* Find length of EXPLICIT tag */
    398 		ret = ASN1_object_size(ndef, i, ttag);
    399 		if (out)
    400 			{
    401 			/* Output tag and item */
    402 			ASN1_put_object(out, ndef, i, ttag, tclass);
    403 			ASN1_item_ex_i2d(pval, out, ASN1_ITEM_ptr(tt->item),
    404 								-1, iclass);
    405 			if (ndef == 2)
    406 				ASN1_put_eoc(out);
    407 			}
    408 		return ret;
    409 		}
    410 
    411 	/* Either normal or IMPLICIT tagging: combine class and flags */
    412 	return ASN1_item_ex_i2d(pval, out, ASN1_ITEM_ptr(tt->item),
    413 						ttag, tclass | iclass);
    414 
    415 }
    416 
    417 /* Temporary structure used to hold DER encoding of items for SET OF */
    418 
    419 typedef	struct {
    420 	unsigned char *data;
    421 	int length;
    422 	ASN1_VALUE *field;
    423 } DER_ENC;
    424 
    425 static int der_cmp(const void *a, const void *b)
    426 	{
    427 	const DER_ENC *d1 = a, *d2 = b;
    428 	int cmplen, i;
    429 	cmplen = (d1->length < d2->length) ? d1->length : d2->length;
    430 	i = memcmp(d1->data, d2->data, cmplen);
    431 	if (i)
    432 		return i;
    433 	return d1->length - d2->length;
    434 	}
    435 
    436 /* Output the content octets of SET OF or SEQUENCE OF */
    437 
    438 static int asn1_set_seq_out(STACK_OF(ASN1_VALUE) *sk, unsigned char **out,
    439 					int skcontlen, const ASN1_ITEM *item,
    440 					int do_sort, int iclass)
    441 	{
    442 	size_t i;
    443 	ASN1_VALUE *skitem;
    444 	unsigned char *tmpdat = NULL, *p = NULL;
    445 	DER_ENC *derlst = NULL, *tder;
    446 	if (do_sort)
    447 		 {
    448 		/* Don't need to sort less than 2 items */
    449 		if (sk_ASN1_VALUE_num(sk) < 2)
    450 			do_sort = 0;
    451 		else
    452 			{
    453 			derlst = OPENSSL_malloc(sk_ASN1_VALUE_num(sk)
    454 						* sizeof(*derlst));
    455 			if (!derlst)
    456 				return 0;
    457 			tmpdat = OPENSSL_malloc(skcontlen);
    458 			if (!tmpdat)
    459 				{
    460 				OPENSSL_free(derlst);
    461 				return 0;
    462 				}
    463 			}
    464 		}
    465 	/* If not sorting just output each item */
    466 	if (!do_sort)
    467 		{
    468 		for (i = 0; i < sk_ASN1_VALUE_num(sk); i++)
    469 			{
    470 			skitem = sk_ASN1_VALUE_value(sk, i);
    471 			ASN1_item_ex_i2d(&skitem, out, item, -1, iclass);
    472 			}
    473 		return 1;
    474 		}
    475 	p = tmpdat;
    476 
    477 	/* Doing sort: build up a list of each member's DER encoding */
    478 	for (i = 0, tder = derlst; i < sk_ASN1_VALUE_num(sk); i++, tder++)
    479 		{
    480 		skitem = sk_ASN1_VALUE_value(sk, i);
    481 		tder->data = p;
    482 		tder->length = ASN1_item_ex_i2d(&skitem, &p, item, -1, iclass);
    483 		tder->field = skitem;
    484 		}
    485 
    486 	/* Now sort them */
    487 	qsort(derlst, sk_ASN1_VALUE_num(sk), sizeof(*derlst), der_cmp);
    488 	/* Output sorted DER encoding */
    489 	p = *out;
    490 	for (i = 0, tder = derlst; i < sk_ASN1_VALUE_num(sk); i++, tder++)
    491 		{
    492 		memcpy(p, tder->data, tder->length);
    493 		p += tder->length;
    494 		}
    495 	*out = p;
    496 	/* If do_sort is 2 then reorder the STACK */
    497 	if (do_sort == 2)
    498 		{
    499 		for (i = 0, tder = derlst; i < sk_ASN1_VALUE_num(sk);
    500 							i++, tder++)
    501 			(void)sk_ASN1_VALUE_set(sk, i, tder->field);
    502 		}
    503 	OPENSSL_free(derlst);
    504 	OPENSSL_free(tmpdat);
    505 	return 1;
    506 	}
    507 
    508 static int asn1_i2d_ex_primitive(ASN1_VALUE **pval, unsigned char **out,
    509 				const ASN1_ITEM *it, int tag, int aclass)
    510 	{
    511 	int len;
    512 	int utype;
    513 	int usetag;
    514 	int ndef = 0;
    515 
    516 	utype = it->utype;
    517 
    518 	/* Get length of content octets and maybe find
    519 	 * out the underlying type.
    520 	 */
    521 
    522 	len = asn1_ex_i2c(pval, NULL, &utype, it);
    523 
    524 	/* If SEQUENCE, SET or OTHER then header is
    525 	 * included in pseudo content octets so don't
    526 	 * include tag+length. We need to check here
    527 	 * because the call to asn1_ex_i2c() could change
    528 	 * utype.
    529 	 */
    530 	if ((utype == V_ASN1_SEQUENCE) || (utype == V_ASN1_SET) ||
    531 	   (utype == V_ASN1_OTHER))
    532 		usetag = 0;
    533 	else usetag = 1;
    534 
    535 	/* -1 means omit type */
    536 
    537 	if (len == -1)
    538 		return 0;
    539 
    540 	/* -2 return is special meaning use ndef */
    541 	if (len == -2)
    542 		{
    543 		ndef = 2;
    544 		len = 0;
    545 		}
    546 
    547 	/* If not implicitly tagged get tag from underlying type */
    548 	if (tag == -1) tag = utype;
    549 
    550 	/* Output tag+length followed by content octets */
    551 	if (out)
    552 		{
    553 		if (usetag)
    554 			ASN1_put_object(out, ndef, len, tag, aclass);
    555 		asn1_ex_i2c(pval, *out, &utype, it);
    556 		if (ndef)
    557 			ASN1_put_eoc(out);
    558 		else
    559 			*out += len;
    560 		}
    561 
    562 	if (usetag)
    563 		return ASN1_object_size(ndef, len, tag);
    564 	return len;
    565 	}
    566 
    567 /* Produce content octets from a structure */
    568 
    569 int asn1_ex_i2c(ASN1_VALUE **pval, unsigned char *cout, int *putype,
    570 				const ASN1_ITEM *it)
    571 	{
    572 	ASN1_BOOLEAN *tbool = NULL;
    573 	ASN1_STRING *strtmp;
    574 	ASN1_OBJECT *otmp;
    575 	int utype;
    576 	const unsigned char *cont;
    577 	unsigned char c;
    578 	int len;
    579 	const ASN1_PRIMITIVE_FUNCS *pf;
    580 	pf = it->funcs;
    581 	if (pf && pf->prim_i2c)
    582 		return pf->prim_i2c(pval, cout, putype, it);
    583 
    584 	/* Should type be omitted? */
    585 	if ((it->itype != ASN1_ITYPE_PRIMITIVE)
    586 		|| (it->utype != V_ASN1_BOOLEAN))
    587 		{
    588 		if (!*pval) return -1;
    589 		}
    590 
    591 	if (it->itype == ASN1_ITYPE_MSTRING)
    592 		{
    593 		/* If MSTRING type set the underlying type */
    594 		strtmp = (ASN1_STRING *)*pval;
    595 		utype = strtmp->type;
    596 		*putype = utype;
    597 		}
    598 	else if (it->utype == V_ASN1_ANY)
    599 		{
    600 		/* If ANY set type and pointer to value */
    601 		ASN1_TYPE *typ;
    602 		typ = (ASN1_TYPE *)*pval;
    603 		utype = typ->type;
    604 		*putype = utype;
    605 		pval = &typ->value.asn1_value;
    606 		}
    607 	else utype = *putype;
    608 
    609 	switch(utype)
    610 		{
    611 		case V_ASN1_OBJECT:
    612 		otmp = (ASN1_OBJECT *)*pval;
    613 		cont = otmp->data;
    614 		len = otmp->length;
    615 		break;
    616 
    617 		case V_ASN1_NULL:
    618 		cont = NULL;
    619 		len = 0;
    620 		break;
    621 
    622 		case V_ASN1_BOOLEAN:
    623 		tbool = (ASN1_BOOLEAN *)pval;
    624 		if (*tbool == -1)
    625 			return -1;
    626 		if (it->utype != V_ASN1_ANY)
    627 			{
    628 			/* Default handling if value == size field then omit */
    629 			if (*tbool && (it->size > 0))
    630 				return -1;
    631 			if (!*tbool && !it->size)
    632 				return -1;
    633 			}
    634 		c = (unsigned char)*tbool;
    635 		cont = &c;
    636 		len = 1;
    637 		break;
    638 
    639 		case V_ASN1_BIT_STRING:
    640 		return i2c_ASN1_BIT_STRING((ASN1_BIT_STRING *)*pval,
    641 							cout ? &cout : NULL);
    642 		break;
    643 
    644 		case V_ASN1_INTEGER:
    645 		case V_ASN1_NEG_INTEGER:
    646 		case V_ASN1_ENUMERATED:
    647 		case V_ASN1_NEG_ENUMERATED:
    648 		/* These are all have the same content format
    649 		 * as ASN1_INTEGER
    650 		 */
    651 		return i2c_ASN1_INTEGER((ASN1_INTEGER *)*pval,
    652 							cout ? &cout : NULL);
    653 		break;
    654 
    655 		case V_ASN1_OCTET_STRING:
    656 		case V_ASN1_NUMERICSTRING:
    657 		case V_ASN1_PRINTABLESTRING:
    658 		case V_ASN1_T61STRING:
    659 		case V_ASN1_VIDEOTEXSTRING:
    660 		case V_ASN1_IA5STRING:
    661 		case V_ASN1_UTCTIME:
    662 		case V_ASN1_GENERALIZEDTIME:
    663 		case V_ASN1_GRAPHICSTRING:
    664 		case V_ASN1_VISIBLESTRING:
    665 		case V_ASN1_GENERALSTRING:
    666 		case V_ASN1_UNIVERSALSTRING:
    667 		case V_ASN1_BMPSTRING:
    668 		case V_ASN1_UTF8STRING:
    669 		case V_ASN1_SEQUENCE:
    670 		case V_ASN1_SET:
    671 		default:
    672 		/* All based on ASN1_STRING and handled the same */
    673 		strtmp = (ASN1_STRING *)*pval;
    674 		/* Special handling for NDEF */
    675 		if ((it->size == ASN1_TFLG_NDEF)
    676 			&& (strtmp->flags & ASN1_STRING_FLAG_NDEF))
    677 			{
    678 			if (cout)
    679 				{
    680 				strtmp->data = cout;
    681 				strtmp->length = 0;
    682 				}
    683 			/* Special return code */
    684 			return -2;
    685 			}
    686 		cont = strtmp->data;
    687 		len = strtmp->length;
    688 
    689 		break;
    690 
    691 		}
    692 	if (cout && len)
    693 		memcpy(cout, cont, len);
    694 	return len;
    695 	}
    696