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openssl/crypto/asn1/tasn_dec.c
Dr. Stephen Henson c962479bdf Fix ASN1 bug when decoding OTHER type. 
Various S/MIME DSA related fixes.
2001-04-21 12:06:01 +00:00

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/* tasn_dec.c */
/* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL
* project 2000.
*/
/* ====================================================================
* Copyright (c) 2000 The OpenSSL Project. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. All advertising materials mentioning features or use of this
* software must display the following acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
*
* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For written permission, please contact
* licensing@OpenSSL.org.
*
* 5. Products derived from this software may not be called "OpenSSL"
* nor may "OpenSSL" appear in their names without prior written
* permission of the OpenSSL Project.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
*
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
* ====================================================================
*
* This product includes cryptographic software written by Eric Young
* (eay@cryptsoft.com). This product includes software written by Tim
* Hudson (tjh@cryptsoft.com).
*
*/
#include <stddef.h>
#include <string.h>
#include <openssl/asn1.h>
#include <openssl/asn1t.h>
#include <openssl/objects.h>
#include <openssl/buffer.h>
#include <openssl/err.h>
static int asn1_check_eoc(unsigned char **in, long len);
static int asn1_collect(BUF_MEM *buf, unsigned char **in, long len, char inf, int tag, int aclass);
static int collect_data(BUF_MEM *buf, unsigned char **p, long plen);
static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass, char *inf, char *cst,
unsigned char **in, long len, int exptag, int expclass, char opt, ASN1_TLC *ctx);
static int asn1_template_ex_d2i(ASN1_VALUE **pval, unsigned char **in, long len, const ASN1_TEMPLATE *tt, char opt, ASN1_TLC *ctx);
static int asn1_template_noexp_d2i(ASN1_VALUE **val, unsigned char **in, long len, const ASN1_TEMPLATE *tt, char opt, ASN1_TLC *ctx);
static int asn1_d2i_ex_primitive(ASN1_VALUE **pval, unsigned char **in, long len,
const ASN1_ITEM *it, int tag, int aclass, char opt, ASN1_TLC *ctx);
/* Macro to initialize and invalidate the cache */
#define asn1_tlc_clear(c) if(c) (c)->valid = 0
/* Decode an ASN1 item, this currently behaves just
* like a standard 'd2i' function. 'in' points to
* a buffer to read the data from, in future we will
* have more advanced versions that can input data
* a piece at a time and this will simply be a special
* case.
*/
ASN1_VALUE *ASN1_item_d2i(ASN1_VALUE **pval, unsigned char **in, long len, const ASN1_ITEM *it)
{
ASN1_TLC c;
ASN1_VALUE *ptmpval = NULL;
if(!pval) pval = &ptmpval;
asn1_tlc_clear(&c);
if(ASN1_item_ex_d2i(pval, in, len, it, -1, 0, 0, &c) > 0)
return *pval;
return NULL;
}
int ASN1_template_d2i(ASN1_VALUE **pval, unsigned char **in, long len, const ASN1_TEMPLATE *tt)
{
ASN1_TLC c;
asn1_tlc_clear(&c);
return asn1_template_ex_d2i(pval, in, len, tt, 0, &c);
}
/* Decode an item, taking care of IMPLICIT tagging, if any.
* If 'opt' set and tag mismatch return -1 to handle OPTIONAL
*/
int ASN1_item_ex_d2i(ASN1_VALUE **pval, unsigned char **in, long len, const ASN1_ITEM *it,
int tag, int aclass, char opt, ASN1_TLC *ctx)
{
const ASN1_TEMPLATE *tt, *errtt = NULL;
const ASN1_COMPAT_FUNCS *cf;
const ASN1_EXTERN_FUNCS *ef;
const ASN1_AUX *aux = it->funcs;
ASN1_aux_cb *asn1_cb;
unsigned char *p, *q, imphack = 0, oclass;
char seq_eoc, seq_nolen, cst, isopt;
long tmplen;
int i;
int otag;
int ret = 0;
ASN1_VALUE *pchval, **pchptr, *ptmpval;
if(!pval) return 0;
if(aux && aux->asn1_cb) asn1_cb = aux->asn1_cb;
else asn1_cb = 0;
switch(it->itype) {
case ASN1_ITYPE_PRIMITIVE:
if(it->templates) {
/* tagging or OPTIONAL is currently illegal on an item template
* because the flags can't get passed down. In practice this isn't
* a problem: we include the relevant flags from the item template
* in the template itself.
*/
if ((tag != -1) || opt) {
ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_ILLEGAL_OPTIONS_ON_ITEM_TEMPLATE);
goto err;
}
return asn1_template_ex_d2i(pval, in, len, it->templates, opt, ctx);
}
return asn1_d2i_ex_primitive(pval, in, len, it, tag, aclass, opt, ctx);
break;
case ASN1_ITYPE_MSTRING:
p = *in;
/* Just read in tag and class */
ret = asn1_check_tlen(NULL, &otag, &oclass, NULL, NULL, &p, len, -1, 0, 1, ctx);
if(!ret) {
ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
goto err;
}
/* Must be UNIVERSAL class */
if(oclass != V_ASN1_UNIVERSAL) {
/* If OPTIONAL, assume this is OK */
if(opt) return -1;
ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MSTRING_NOT_UNIVERSAL);
goto err;
}
/* Check tag matches bit map */
if(!(ASN1_tag2bit(otag) & it->utype)) {
/* If OPTIONAL, assume this is OK */
if(opt) return -1;
ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MSTRING_WRONG_TAG);
goto err;
}
return asn1_d2i_ex_primitive(pval, in, len, it, otag, 0, 0, ctx);
case ASN1_ITYPE_EXTERN:
/* Use new style d2i */
ef = it->funcs;
return ef->asn1_ex_d2i(pval, in, len, it, tag, aclass, opt, ctx);
case ASN1_ITYPE_COMPAT:
/* we must resort to old style evil hackery */
cf = it->funcs;
/* If OPTIONAL see if it is there */
if(opt) {
int exptag;
p = *in;
if(tag == -1) exptag = it->utype;
else exptag = tag;
/* Don't care about anything other than presence of expected tag */
ret = asn1_check_tlen(NULL, NULL, NULL, NULL, NULL, &p, len, exptag, aclass, 1, ctx);
if(!ret) {
ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
goto err;
}
if(ret == -1) return -1;
}
/* This is the old style evil hack IMPLICIT handling:
* since the underlying code is expecting a tag and
* class other than the one present we change the
* buffer temporarily then change it back afterwards.
* This doesn't and never did work for tags > 30.
*
* Yes this is *horrible* but it is only needed for
* old style d2i which will hopefully not be around
* for much longer.
* FIXME: should copy the buffer then modify it so
* the input buffer can be const: we should *always*
* copy because the old style d2i might modify the
* buffer.
*/
if(tag != -1) {
p = *in;
imphack = *p;
*p = (unsigned char)((*p & V_ASN1_CONSTRUCTED) | it->utype);
}
ptmpval = cf->asn1_d2i(pval, in, len);
if(tag != -1) *p = imphack;
if(ptmpval) return 1;
ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
goto err;
case ASN1_ITYPE_CHOICE:
if(asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it))
goto auxerr;
/* Allocate structure */
if(!*pval) {
if(!ASN1_item_ex_new(pval, it)) {
ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
goto err;
}
}
/* CHOICE type, try each possibility in turn */
pchval = NULL;
p = *in;
for(i = 0, tt=it->templates; i < it->tcount; i++, tt++) {
pchptr = asn1_get_field_ptr(pval, tt);
/* We mark field as OPTIONAL so its absence
* can be recognised.
*/
ret = asn1_template_ex_d2i(pchptr, &p, len, tt, 1, ctx);
/* If field not present, try the next one */
if(ret == -1) continue;
/* If positive return, read OK, break loop */
if(ret > 0) break;
/* Otherwise must be an ASN1 parsing error */
errtt = tt;
ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
goto err;
}
/* Did we fall off the end without reading anything? */
if(i == it->tcount) {
/* If OPTIONAL, this is OK */
if(opt) {
/* Free and zero it */
ASN1_item_ex_free(pval, it);
return -1;
}
ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_NO_MATCHING_CHOICE_TYPE);
goto err;
}
asn1_set_choice_selector(pval, i, it);
*in = p;
if(asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it))
goto auxerr;
return 1;
case ASN1_ITYPE_SEQUENCE:
p = *in;
tmplen = len;
/* If no IMPLICIT tagging set to SEQUENCE, UNIVERSAL */
if(tag == -1) {
tag = V_ASN1_SEQUENCE;
aclass = V_ASN1_UNIVERSAL;
}
/* Get SEQUENCE length and update len, p */
ret = asn1_check_tlen(&len, NULL, NULL, &seq_eoc, &cst, &p, len, tag, aclass, opt, ctx);
if(!ret) {
ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
goto err;
} else if(ret == -1) return -1;
if(aux && (aux->flags & ASN1_AFLG_BROKEN)) {
len = tmplen - (p - *in);
seq_nolen = 1;
} else seq_nolen = seq_eoc; /* If indefinite we don't do a length check */
if(!cst) {
ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_SEQUENCE_NOT_CONSTRUCTED);
goto err;
}
if(!*pval) {
if(!ASN1_item_ex_new(pval, it)) {
ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
goto err;
}
}
if(asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it))
goto auxerr;
/* Get each field entry */
for(i = 0, tt = it->templates; i < it->tcount; i++, tt++) {
const ASN1_TEMPLATE *seqtt;
ASN1_VALUE **pseqval;
seqtt = asn1_do_adb(pval, tt, 1);
if(!seqtt) goto err;
pseqval = asn1_get_field_ptr(pval, seqtt);
/* Have we ran out of data? */
if(!len) break;
q = p;
if(asn1_check_eoc(&p, len)) {
if(!seq_eoc) {
ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_UNEXPECTED_EOC);
goto err;
}
len -= p - q;
seq_eoc = 0;
q = p;
break;
}
/* This determines the OPTIONAL flag value. The field cannot
* be omitted if it is the last of a SEQUENCE and there is
* still data to be read. This isn't strictly necessary but
* it increases efficiency in some cases.
*/
if(i == (it->tcount - 1)) isopt = 0;
else isopt = (char)(seqtt->flags & ASN1_TFLG_OPTIONAL);
/* attempt to read in field, allowing each to be OPTIONAL */
ret = asn1_template_ex_d2i(pseqval, &p, len, seqtt, isopt, ctx);
if(!ret) {
errtt = seqtt;
goto err;
} else if(ret == -1) {
/* OPTIONAL component absent. Free and zero the field
*/
ASN1_template_free(pseqval, seqtt);
continue;
}
/* Update length */
len -= p - q;
}
/* Check for EOC if expecting one */
if(seq_eoc && !asn1_check_eoc(&p, len)) {
ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MISSING_EOC);
goto err;
}
/* Check all data read */
if(!seq_nolen && len) {
ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_SEQUENCE_LENGTH_MISMATCH);
goto err;
}
/* If we get here we've got no more data in the SEQUENCE,
* however we may not have read all fields so check all
* remaining are OPTIONAL and clear any that are.
*/
for(; i < it->tcount; tt++, i++) {
const ASN1_TEMPLATE *seqtt;
seqtt = asn1_do_adb(pval, tt, 1);
if(!seqtt) goto err;
if(seqtt->flags & ASN1_TFLG_OPTIONAL) {
ASN1_VALUE **pseqval;
pseqval = asn1_get_field_ptr(pval, seqtt);
ASN1_template_free(pseqval, seqtt);
} else {
errtt = seqtt;
ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_FIELD_MISSING);
goto err;
}
}
/* Save encoding */
if(!asn1_enc_save(pval, *in, p - *in, it)) goto auxerr;
*in = p;
if(asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it))
goto auxerr;
return 1;
default:
return 0;
}
auxerr:
ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_AUX_ERROR);
err:
ASN1_item_ex_free(pval, it);
if(errtt) ERR_add_error_data(4, "Field=", errtt->field_name, ", Type=", it->sname);
else ERR_add_error_data(2, "Type=", it->sname);
return 0;
}
/* Templates are handled with two separate functions. One handles any EXPLICIT tag and the other handles the
* rest.
*/
int asn1_template_ex_d2i(ASN1_VALUE **val, unsigned char **in, long inlen, const ASN1_TEMPLATE *tt, char opt, ASN1_TLC *ctx)
{
int flags, aclass;
int ret;
long len;
unsigned char *p, *q;
char exp_eoc;
if(!val) return 0;
flags = tt->flags;
aclass = flags & ASN1_TFLG_TAG_CLASS;
p = *in;
/* Check if EXPLICIT tag expected */
if(flags & ASN1_TFLG_EXPTAG) {
char cst;
/* Need to work out amount of data available to the inner content and where it
* starts: so read in EXPLICIT header to get the info.
*/
ret = asn1_check_tlen(&len, NULL, NULL, &exp_eoc, &cst, &p, inlen, tt->tag, aclass, opt, ctx);
q = p;
if(!ret) {
ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
return 0;
} else if(ret == -1) return -1;
if(!cst) {
ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ASN1_R_EXPLICIT_TAG_NOT_CONSTRUCTED);
return 0;
}
/* We've found the field so it can't be OPTIONAL now */
ret = asn1_template_noexp_d2i(val, &p, len, tt, 0, ctx);
if(!ret) {
ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
return 0;
}
/* We read the field in OK so update length */
len -= p - q;
if(exp_eoc) {
/* If NDEF we must have an EOC here */
if(!asn1_check_eoc(&p, len)) {
ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ASN1_R_MISSING_EOC);
goto err;
}
} else {
/* Otherwise we must hit the EXPLICIT tag end or its an error */
if(len) {
ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ASN1_R_EXPLICIT_LENGTH_MISMATCH);
goto err;
}
}
} else
return asn1_template_noexp_d2i(val, in, inlen, tt, opt, ctx);
*in = p;
return 1;
err:
ASN1_template_free(val, tt);
*val = NULL;
return 0;
}
static int asn1_template_noexp_d2i(ASN1_VALUE **val, unsigned char **in, long len, const ASN1_TEMPLATE *tt, char opt, ASN1_TLC *ctx)
{
int flags, aclass;
int ret;
unsigned char *p, *q;
if(!val) return 0;
flags = tt->flags;
aclass = flags & ASN1_TFLG_TAG_CLASS;
p = *in;
q = p;
if(flags & ASN1_TFLG_SK_MASK) {
/* SET OF, SEQUENCE OF */
int sktag, skaclass;
char sk_eoc;
/* First work out expected inner tag value */
if(flags & ASN1_TFLG_IMPTAG) {
sktag = tt->tag;
skaclass = aclass;
} else {
skaclass = V_ASN1_UNIVERSAL;
if(flags & ASN1_TFLG_SET_OF) sktag = V_ASN1_SET;
else sktag = V_ASN1_SEQUENCE;
}
/* Get the tag */
ret = asn1_check_tlen(&len, NULL, NULL, &sk_eoc, NULL, &p, len, sktag, skaclass, opt, ctx);
if(!ret) {
ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
return 0;
} else if(ret == -1) return -1;
if(!*val) *val = (ASN1_VALUE *)sk_new_null();
else {
/* We've got a valid STACK: free up any items present */
STACK *sktmp = (STACK *)*val;
ASN1_VALUE *vtmp;
while(sk_num(sktmp) > 0) {
vtmp = (ASN1_VALUE *)sk_pop(sktmp);
ASN1_item_ex_free(&vtmp, ASN1_ITEM_ptr(tt->item));
}
}
if(!*val) {
ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ERR_R_MALLOC_FAILURE);
goto err;
}
/* Read as many items as we can */
while(len > 0) {
ASN1_VALUE *skfield;
q = p;
/* See if EOC found */
if(asn1_check_eoc(&p, len)) {
if(!sk_eoc) {
ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ASN1_R_UNEXPECTED_EOC);
goto err;
}
len -= p - q;
sk_eoc = 0;
break;
}
skfield = NULL;
if(!ASN1_item_ex_d2i(&skfield, &p, len, ASN1_ITEM_ptr(tt->item), -1, 0, 0, ctx)) {
ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ERR_R_NESTED_ASN1_ERROR);
goto err;
}
len -= p - q;
if(!sk_push((STACK *)*val, (char *)skfield)) {
ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ERR_R_MALLOC_FAILURE);
goto err;
}
}
if(sk_eoc) {
ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ASN1_R_MISSING_EOC);
goto err;
}
} else if(flags & ASN1_TFLG_IMPTAG) {
/* IMPLICIT tagging */
ret = ASN1_item_ex_d2i(val, &p, len, ASN1_ITEM_ptr(tt->item), tt->tag, aclass, opt, ctx);
if(!ret) {
ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ERR_R_NESTED_ASN1_ERROR);
goto err;
} else if(ret == -1) return -1;
} else {
/* Nothing special */
ret = ASN1_item_ex_d2i(val, &p, len, ASN1_ITEM_ptr(tt->item), -1, 0, opt, ctx);
if(!ret) {
ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ERR_R_NESTED_ASN1_ERROR);
goto err;
} else if(ret == -1) return -1;
}
*in = p;
return 1;
err:
ASN1_template_free(val, tt);
*val = NULL;
return 0;
}
static int asn1_d2i_ex_primitive(ASN1_VALUE **pval, unsigned char **in, long inlen,
const ASN1_ITEM *it,
int tag, int aclass, char opt, ASN1_TLC *ctx)
{
int ret = 0, utype;
long plen;
char cst, inf, free_cont = 0;
unsigned char *p;
BUF_MEM buf;
unsigned char *cont = NULL;
long len;
if(!pval) {
ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_NULL);
return 0; /* Should never happen */
}
if(it->itype == ASN1_ITYPE_MSTRING) {
utype = tag;
tag = -1;
} else utype = it->utype;
if(utype == V_ASN1_ANY) {
/* If type is ANY need to figure out type from tag */
unsigned char oclass;
if(tag >= 0) {
ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_TAGGED_ANY);
return 0;
}
if(opt) {
ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_OPTIONAL_ANY);
return 0;
}
p = *in;
ret = asn1_check_tlen(NULL, &utype, &oclass, NULL, NULL, &p, inlen, -1, 0, 0, ctx);
if(!ret) {
ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_NESTED_ASN1_ERROR);
return 0;
}
if(oclass != V_ASN1_UNIVERSAL) utype = V_ASN1_OTHER;
}
if(tag == -1) {
tag = utype;
aclass = V_ASN1_UNIVERSAL;
}
p = *in;
/* Check header */
ret = asn1_check_tlen(&plen, NULL, NULL, &inf, &cst, &p, inlen, tag, aclass, opt, ctx);
if(!ret) {
ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_NESTED_ASN1_ERROR);
return 0;
} else if(ret == -1) return -1;
/* SEQUENCE, SET and "OTHER" are left in encoded form */
if((utype == V_ASN1_SEQUENCE) || (utype == V_ASN1_SET) || (utype == V_ASN1_OTHER)) {
/* Clear context cache for type OTHER because the auto clear when
* we have a exact match wont work
*/
if(utype == V_ASN1_OTHER) {
asn1_tlc_clear(ctx);
/* SEQUENCE and SET must be constructed */
} else if(!cst) {
ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_TYPE_NOT_CONSTRUCTED);
return 0;
}
cont = *in;
/* If indefinite length constructed find the real end */
if(inf) {
if(!asn1_collect(NULL, &p, plen, inf, -1, -1)) goto err;
len = p - cont;
} else {
len = p - cont + plen;
p += plen;
buf.data = NULL;
}
} else if(cst) {
buf.length = 0;
buf.max = 0;
buf.data = NULL;
/* Should really check the internal tags are correct but
* some things may get this wrong. The relevant specs
* say that constructed string types should be OCTET STRINGs
* internally irrespective of the type. So instead just check
* for UNIVERSAL class and ignore the tag.
*/
if(!asn1_collect(&buf, &p, plen, inf, -1, V_ASN1_UNIVERSAL)) goto err;
len = buf.length;
/* Append a final null to string */
if(!BUF_MEM_grow(&buf, len + 1)) {
ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_MALLOC_FAILURE);
return 0;
}
buf.data[len] = 0;
cont = (unsigned char *)buf.data;
free_cont = 1;
} else {
cont = p;
len = plen;
p += plen;
}
/* We now have content length and type: translate into a structure */
if(!asn1_ex_c2i(pval, cont, len, utype, &free_cont, it)) goto err;
*in = p;
ret = 1;
err:
if(free_cont && buf.data) OPENSSL_free(buf.data);
return ret;
}
/* Translate ASN1 content octets into a structure */
int asn1_ex_c2i(ASN1_VALUE **pval, unsigned char *cont, int len, int utype, char *free_cont, const ASN1_ITEM *it)
{
ASN1_STRING *stmp;
ASN1_TYPE *typ = NULL;
int ret = 0;
const ASN1_PRIMITIVE_FUNCS *pf;
ASN1_INTEGER **tint;
pf = it->funcs;
if(pf && pf->prim_c2i) return pf->prim_c2i(pval, cont, len, utype, free_cont, it);
/* If ANY type clear type and set pointer to internal value */
if(it->utype == V_ASN1_ANY) {
if(!*pval) {
typ = ASN1_TYPE_new();
*pval = (ASN1_VALUE *)typ;
} else typ = (ASN1_TYPE *)*pval;
if(utype != typ->type) ASN1_TYPE_set(typ, utype, NULL);
pval = (ASN1_VALUE **)&typ->value.ptr;
}
switch(utype) {
case V_ASN1_OBJECT:
if(!c2i_ASN1_OBJECT((ASN1_OBJECT **)pval, &cont, len)) goto err;
break;
case V_ASN1_NULL:
if(len) {
ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_NULL_IS_WRONG_LENGTH);
goto err;
}
*pval = (ASN1_VALUE *)1;
break;
case V_ASN1_BOOLEAN:
if(len != 1) {
ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_BOOLEAN_IS_WRONG_LENGTH);
goto err;
} else {
ASN1_BOOLEAN *tbool;
tbool = (ASN1_BOOLEAN *)pval;
*tbool = *cont;
}
break;
case V_ASN1_BIT_STRING:
if(!c2i_ASN1_BIT_STRING((ASN1_BIT_STRING **)pval, &cont, len)) goto err;
break;
case V_ASN1_INTEGER:
case V_ASN1_NEG_INTEGER:
case V_ASN1_ENUMERATED:
case V_ASN1_NEG_ENUMERATED:
tint = (ASN1_INTEGER **)pval;
if(!c2i_ASN1_INTEGER(tint, &cont, len)) goto err;
/* Fixup type to match the expected form */
(*tint)->type = utype | ((*tint)->type & V_ASN1_NEG);
break;
case V_ASN1_OCTET_STRING:
case V_ASN1_NUMERICSTRING:
case V_ASN1_PRINTABLESTRING:
case V_ASN1_T61STRING:
case V_ASN1_VIDEOTEXSTRING:
case V_ASN1_IA5STRING:
case V_ASN1_UTCTIME:
case V_ASN1_GENERALIZEDTIME:
case V_ASN1_GRAPHICSTRING:
case V_ASN1_VISIBLESTRING:
case V_ASN1_GENERALSTRING:
case V_ASN1_UNIVERSALSTRING:
case V_ASN1_BMPSTRING:
case V_ASN1_UTF8STRING:
case V_ASN1_OTHER:
case V_ASN1_SET:
case V_ASN1_SEQUENCE:
default:
/* All based on ASN1_STRING and handled the same */
if(!*pval) {
stmp = ASN1_STRING_type_new(utype);
if(!stmp) {
ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_MALLOC_FAILURE);
goto err;
}
*pval = (ASN1_VALUE *)stmp;
} else {
stmp = (ASN1_STRING *)*pval;
stmp->type = utype;
}
/* If we've already allocated a buffer use it */
if(*free_cont) {
if(stmp->data) OPENSSL_free(stmp->data);
stmp->data = cont;
stmp->length = len;
*free_cont = 0;
} else {
if(!ASN1_STRING_set(stmp, cont, len)) {
ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_MALLOC_FAILURE);
ASN1_STRING_free(stmp);
*pval = NULL;
goto err;
}
}
break;
}
/* If ASN1_ANY and NULL type fix up value */
if(typ && utype==V_ASN1_NULL) typ->value.ptr = NULL;
ret = 1;
err:
if(!ret) ASN1_TYPE_free(typ);
return ret;
}
/* This function collects the asn1 data from a constructred string
* type into a buffer. The values of 'in' and 'len' should refer
* to the contents of the constructed type and 'inf' should be set
* if it is indefinite length. If 'buf' is NULL then we just want
* to find the end of the current structure: useful for indefinite
* length constructed stuff.
*/
static int asn1_collect(BUF_MEM *buf, unsigned char **in, long len, char inf, int tag, int aclass)
{
unsigned char *p, *q;
long plen;
char cst, ininf;
p = *in;
inf &= 1;
/* If no buffer and not indefinite length constructed just pass over the encoded data */
if(!buf && !inf) {
*in += len;
return 1;
}
while(len > 0) {
q = p;
/* Check for EOC */
if(asn1_check_eoc(&p, len)) {
/* EOC is illegal outside indefinite length constructed form */
if(!inf) {
ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_UNEXPECTED_EOC);
return 0;
}
inf = 0;
break;
}
if(!asn1_check_tlen(&plen, NULL, NULL, &ininf, &cst, &p, len, tag, aclass, 0, NULL)) {
ASN1err(ASN1_F_ASN1_COLLECT, ERR_R_NESTED_ASN1_ERROR);
return 0;
}
/* If indefinite length constructed update max length */
if(cst) {
if(!asn1_collect(buf, &p, plen, ininf, tag, aclass)) return 0;
} else {
if(!collect_data(buf, &p, plen)) return 0;
}
len -= p - q;
}
if(inf) {
ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_MISSING_EOC);
return 0;
}
*in = p;
return 1;
}
static int collect_data(BUF_MEM *buf, unsigned char **p, long plen)
{
int len;
if(buf) {
len = buf->length;
if(!BUF_MEM_grow(buf, len + plen)) {
ASN1err(ASN1_F_COLLECT_DATA, ERR_R_MALLOC_FAILURE);
return 0;
}
memcpy(buf->data + len, *p, plen);
}
*p += plen;
return 1;
}
/* Check for ASN1 EOC and swallow it if found */
static int asn1_check_eoc(unsigned char **in, long len)
{
unsigned char *p;
if(len < 2) return 0;
p = *in;
if(!p[0] && !p[1]) {
*in += 2;
return 1;
}
return 0;
}
/* Check an ASN1 tag and length: a bit like ASN1_get_object
* but it sets the length for indefinite length constructed
* form, we don't know the exact length but we can set an
* upper bound to the amount of data available minus the
* header length just read.
*/
static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass, char *inf, char *cst,
unsigned char **in, long len, int exptag, int expclass, char opt, ASN1_TLC *ctx)
{
int i;
int ptag, pclass;
long plen;
unsigned char *p, *q;
p = *in;
q = p;
if(ctx && ctx->valid) {
i = ctx->ret;
plen = ctx->plen;
pclass = ctx->pclass;
ptag = ctx->ptag;
p += ctx->hdrlen;
} else {
i = ASN1_get_object(&p, &plen, &ptag, &pclass, len);
if(ctx) {
ctx->ret = i;
ctx->plen = plen;
ctx->pclass = pclass;
ctx->ptag = ptag;
ctx->hdrlen = p - q;
ctx->valid = 1;
/* If definite length, length + header can't exceed total
* amount of data available.
*/
if(!(i & 1) && ((plen + ctx->hdrlen) > len)) {
ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_TOO_LONG);
asn1_tlc_clear(ctx);
return 0;
}
}
}
if(i & 0x80) {
ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_BAD_OBJECT_HEADER);
asn1_tlc_clear(ctx);
return 0;
}
if(exptag >= 0) {
if((exptag != ptag) || (expclass != pclass)) {
/* If type is OPTIONAL, not an error, but indicate missing
* type.
*/
if(opt) return -1;
asn1_tlc_clear(ctx);
ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_WRONG_TAG);
return 0;
}
/* We have a tag and class match, so assume we are going to do something with it */
asn1_tlc_clear(ctx);
}
if(i & 1) plen = len - (p - q);
if(inf) *inf = i & 1;
if(cst) *cst = i & V_ASN1_CONSTRUCTED;
if(olen) *olen = plen;
if(oclass) *oclass = pclass;
if(otag) *otag = ptag;
*in = p;
return 1;
}
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