/* tasn_enc.c */
/* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL
* project 2000.
*/
/* ====================================================================
* Copyright (c) 2000-2004 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 "cryptlib.h"
#include <openssl/asn1.h>
#include <openssl/asn1t.h>
#include <openssl/objects.h>
static int asn1_i2d_ex_primitive(ASN1_VALUE **pval, unsigned char **out,
const ASN1_ITEM *it,
int tag, int aclass);
static int asn1_set_seq_out(STACK_OF(ASN1_VALUE) *sk, unsigned char **out,
int skcontlen, const ASN1_ITEM *item,
int do_sort, int iclass);
static int asn1_template_ex_i2d(ASN1_VALUE **pval, unsigned char **out,
const ASN1_TEMPLATE *tt,
int tag, int aclass);
static int asn1_item_flags_i2d(ASN1_VALUE *val, unsigned char **out,
const ASN1_ITEM *it, int flags);
/* Top level i2d equivalents: the 'ndef' variant instructs the encoder
* to use indefinite length constructed encoding, where appropriate
*/
int ASN1_item_ndef_i2d(ASN1_VALUE *val, unsigned char **out,
const ASN1_ITEM *it)
{
return asn1_item_flags_i2d(val, out, it, ASN1_TFLG_NDEF);
}
int ASN1_item_i2d(ASN1_VALUE *val, unsigned char **out, const ASN1_ITEM *it)
{
return asn1_item_flags_i2d(val, out, it, 0);
}
/* Encode an ASN1 item, this is use by the
* standard 'i2d' function. 'out' points to
* a buffer to output the data to.
*
* The new i2d has one additional feature. If the output
* buffer is NULL (i.e. *out == NULL) then a buffer is
* allocated and populated with the encoding.
*/
static int asn1_item_flags_i2d(ASN1_VALUE *val, unsigned char **out,
const ASN1_ITEM *it, int flags)
{
if (out && !*out)
{
unsigned char *p, *buf;
int len;
len = ASN1_item_ex_i2d(&val, NULL, it, -1, flags);
if (len <= 0)
return len;
buf = OPENSSL_malloc(len);
if (!buf)
return -1;
p = buf;
ASN1_item_ex_i2d(&val, &p, it, -1, flags);
*out = buf;
return len;
}
return ASN1_item_ex_i2d(&val, out, it, -1, flags);
}
/* Encode an item, taking care of IMPLICIT tagging (if any).
* This function performs the normal item handling: it can be
* used in external types.
*/
int ASN1_item_ex_i2d(ASN1_VALUE **pval, unsigned char **out,
const ASN1_ITEM *it, int tag, int aclass)
{
const ASN1_TEMPLATE *tt = NULL;
unsigned char *p = NULL;
int i, seqcontlen, seqlen, ndef = 1;
const ASN1_COMPAT_FUNCS *cf;
const ASN1_EXTERN_FUNCS *ef;
const ASN1_AUX *aux = it->funcs;
ASN1_aux_cb *asn1_cb = 0;
if ((it->itype != ASN1_ITYPE_PRIMITIVE) && !*pval)
return 0;
if (aux && aux->asn1_cb)
asn1_cb = aux->asn1_cb;
switch(it->itype)
{
case ASN1_ITYPE_PRIMITIVE:
if (it->templates)
return asn1_template_ex_i2d(pval, out, it->templates,
tag, aclass);
return asn1_i2d_ex_primitive(pval, out, it, tag, aclass);
break;
case ASN1_ITYPE_MSTRING:
return asn1_i2d_ex_primitive(pval, out, it, -1, aclass);
case ASN1_ITYPE_CHOICE:
if (asn1_cb && !asn1_cb(ASN1_OP_I2D_PRE, pval, it))
return 0;
i = asn1_get_choice_selector(pval, it);
if ((i >= 0) && (i < it->tcount))
{
ASN1_VALUE **pchval;
const ASN1_TEMPLATE *chtt;
chtt = it->templates + i;
pchval = asn1_get_field_ptr(pval, chtt);
return asn1_template_ex_i2d(pchval, out, chtt,
-1, aclass);
}
/* Fixme: error condition if selector out of range */
if (asn1_cb && !asn1_cb(ASN1_OP_I2D_POST, pval, it))
return 0;
break;
case ASN1_ITYPE_EXTERN:
/* If new style i2d it does all the work */
ef = it->funcs;
return ef->asn1_ex_i2d(pval, out, it, tag, aclass);
case ASN1_ITYPE_COMPAT:
/* old style hackery... */
cf = it->funcs;
if (out)
p = *out;
i = cf->asn1_i2d(*pval, out);
/* Fixup for IMPLICIT tag: note this messes up for tags > 30,
* but so did the old code. Tags > 30 are very rare anyway.
*/
if (out && (tag != -1))
*p = aclass | tag | (*p & V_ASN1_CONSTRUCTED);
return i;
case ASN1_ITYPE_NDEF_SEQUENCE:
/* Use indefinite length constructed if requested */
if (aclass & ASN1_TFLG_NDEF) ndef = 2;
/* fall through */
case ASN1_ITYPE_SEQUENCE:
i = asn1_enc_restore(&seqcontlen, out, pval, it);
/* An error occurred */
if (i < 0)
return 0;
/* We have a valid cached encoding... */
if (i > 0)
return seqcontlen;
/* Otherwise carry on */
seqcontlen = 0;
/* If no IMPLICIT tagging set to SEQUENCE, UNIVERSAL */
if (tag == -1)
{
tag = V_ASN1_SEQUENCE;
/* Retain any other flags in aclass */
aclass = (aclass & ~ASN1_TFLG_TAG_CLASS)
| V_ASN1_UNIVERSAL;
}
if (asn1_cb && !asn1_cb(ASN1_OP_I2D_PRE, pval, it))
return 0;
/* First work out sequence content length */
for (i = 0, tt = it->templates; i < it->tcount; tt++, i++)
{
const ASN1_TEMPLATE *seqtt;
ASN1_VALUE **pseqval;
seqtt = asn1_do_adb(pval, tt, 1);
if (!seqtt)
return 0;
pseqval = asn1_get_field_ptr(pval, seqtt);
/* FIXME: check for errors in enhanced version */
seqcontlen += asn1_template_ex_i2d(pseqval, NULL, seqtt,
-1, aclass);
}
seqlen = ASN1_object_size(ndef, seqcontlen, tag);
if (!out)
return seqlen;
/* Output SEQUENCE header */
ASN1_put_object(out, ndef, seqcontlen, tag, aclass);
for (i = 0, tt = it->templates; i < it->tcount; tt++, i++)
{
const ASN1_TEMPLATE *seqtt;
ASN1_VALUE **pseqval;
seqtt = asn1_do_adb(pval, tt, 1);
if (!seqtt)
return 0;
pseqval = asn1_get_field_ptr(pval, seqtt);
/* FIXME: check for errors in enhanced version */
asn1_template_ex_i2d(pseqval, out, seqtt, -1, aclass);
}
if (ndef == 2)
ASN1_put_eoc(out);
if (asn1_cb && !asn1_cb(ASN1_OP_I2D_POST, pval, it))
return 0;
return seqlen;
default:
return 0;
}
return 0;
}
int ASN1_template_i2d(ASN1_VALUE **pval, unsigned char **out,
const ASN1_TEMPLATE *tt)
{
return asn1_template_ex_i2d(pval, out, tt, -1, 0);
}
static int asn1_template_ex_i2d(ASN1_VALUE **pval, unsigned char **out,
const ASN1_TEMPLATE *tt, int tag, int iclass)
{
int i, ret, flags, ttag, tclass, ndef;
flags = tt->flags;
/* Work out tag and class to use: tagging may come
* either from the template or the arguments, not both
* because this would create ambiguity. Additionally
* the iclass argument may contain some additional flags
* which should be noted and passed down to other levels.
*/
if (flags & ASN1_TFLG_TAG_MASK)
{
/* Error if argument and template tagging */
if (tag != -1)
/* FIXME: error code here */
return -1;
/* Get tagging from template */
ttag = tt->tag;
tclass = flags & ASN1_TFLG_TAG_CLASS;
}
else if (tag != -1)
{
/* No template tagging, get from arguments */
ttag = tag;
tclass = iclass & ASN1_TFLG_TAG_CLASS;
}
else
{
ttag = -1;
tclass = 0;
}
/*
* Remove any class mask from iflag.
*/
iclass &= ~ASN1_TFLG_TAG_CLASS;
/* At this point 'ttag' contains the outer tag to use,
* 'tclass' is the class and iclass is any flags passed
* to this function.
*/
/* if template and arguments require ndef, use it */
if ((flags & ASN1_TFLG_NDEF) && (iclass & ASN1_TFLG_NDEF))
ndef = 2;
else ndef = 1;
if (flags & ASN1_TFLG_SK_MASK)
{
/* SET OF, SEQUENCE OF */
STACK_OF(ASN1_VALUE) *sk = (STACK_OF(ASN1_VALUE) *)*pval;
int isset, sktag, skaclass;
int skcontlen, sklen;
ASN1_VALUE *skitem;
if (!*pval)
return 0;
if (flags & ASN1_TFLG_SET_OF)
{
isset = 1;
/* 2 means we reorder */
if (flags & ASN1_TFLG_SEQUENCE_OF)
isset = 2;
}
else isset = 0;
/* Work out inner tag value: if EXPLICIT
* or no tagging use underlying type.
*/
if ((ttag != -1) && !(flags & ASN1_TFLG_EXPTAG))
{
sktag = ttag;
skaclass = tclass;
}
else
{
skaclass = V_ASN1_UNIVERSAL;
if (isset)
sktag = V_ASN1_SET;
else sktag = V_ASN1_SEQUENCE;
}
/* Determine total length of items */
skcontlen = 0;
for (i = 0; i < sk_ASN1_VALUE_num(sk); i++)
{
skitem = sk_ASN1_VALUE_value(sk, i);
skcontlen += ASN1_item_ex_i2d(&skitem, NULL,
ASN1_ITEM_ptr(tt->item),
-1, iclass);
}
sklen = ASN1_object_size(ndef, skcontlen, sktag);
/* If EXPLICIT need length of surrounding tag */
if (flags & ASN1_TFLG_EXPTAG)
ret = ASN1_object_size(ndef, sklen, ttag);
else ret = sklen;
if (!out)
return ret;
/* Now encode this lot... */
/* EXPLICIT tag */
if (flags & ASN1_TFLG_EXPTAG)
ASN1_put_object(out, ndef, sklen, ttag, tclass);
/* SET or SEQUENCE and IMPLICIT tag */
ASN1_put_object(out, ndef, skcontlen, sktag, skaclass);
/* And the stuff itself */
asn1_set_seq_out(sk, out, skcontlen, ASN1_ITEM_ptr(tt->item),
isset, iclass);
if (ndef == 2)
{
ASN1_put_eoc(out);
if (flags & ASN1_TFLG_EXPTAG)
ASN1_put_eoc(out);
}
return ret;
}
if (flags & ASN1_TFLG_EXPTAG)
{
/* EXPLICIT tagging */
/* Find length of tagged item */
i = ASN1_item_ex_i2d(pval, NULL, ASN1_ITEM_ptr(tt->item),
-1, iclass);
if (!i)
return 0;
/* Find length of EXPLICIT tag */
ret = ASN1_object_size(ndef, i, ttag);
if (out)
{
/* Output tag and item */
ASN1_put_object(out, ndef, i, ttag, tclass);
ASN1_item_ex_i2d(pval, out, ASN1_ITEM_ptr(tt->item),
-1, iclass);
if (ndef == 2)
ASN1_put_eoc(out);
}
return ret;
}
/* Either normal or IMPLICIT tagging: combine class and flags */
return ASN1_item_ex_i2d(pval, out, ASN1_ITEM_ptr(tt->item),
ttag, tclass | iclass);
}
/* Temporary structure used to hold DER encoding of items for SET OF */
typedef struct {
unsigned char *data;
int length;
ASN1_VALUE *field;
} DER_ENC;
static int der_cmp(const void *a, const void *b)
{
const DER_ENC *d1 = a, *d2 = b;
int cmplen, i;
cmplen = (d1->length < d2->length) ? d1->length : d2->length;
i = memcmp(d1->data, d2->data, cmplen);
if (i)
return i;
return d1->length - d2->length;
}
/* Output the content octets of SET OF or SEQUENCE OF */
static int asn1_set_seq_out(STACK_OF(ASN1_VALUE) *sk, unsigned char **out,
int skcontlen, const ASN1_ITEM *item,
int do_sort, int iclass)
{
int i;
ASN1_VALUE *skitem;
unsigned char *tmpdat = NULL, *p = NULL;
DER_ENC *derlst = NULL, *tder;
if (do_sort)
{
/* Don't need to sort less than 2 items */
if (sk_ASN1_VALUE_num(sk) < 2)
do_sort = 0;
else
{
derlst = OPENSSL_malloc(sk_ASN1_VALUE_num(sk)
* sizeof(*derlst));
tmpdat = OPENSSL_malloc(skcontlen);
if (!derlst || !tmpdat)
return 0;
}
}
/* If not sorting just output each item */
if (!do_sort)
{
for (i = 0; i < sk_ASN1_VALUE_num(sk); i++)
{
skitem = sk_ASN1_VALUE_value(sk, i);
ASN1_item_ex_i2d(&skitem, out, item, -1, iclass);
}
return 1;
}
p = tmpdat;
/* Doing sort: build up a list of each member's DER encoding */
for (i = 0, tder = derlst; i < sk_ASN1_VALUE_num(sk); i++, tder++)
{
skitem = sk_ASN1_VALUE_value(sk, i);
tder->data = p;
tder->length = ASN1_item_ex_i2d(&skitem, &p, item, -1, iclass);
tder->field = skitem;
}
/* Now sort them */
qsort(derlst, sk_ASN1_VALUE_num(sk), sizeof(*derlst), der_cmp);
/* Output sorted DER encoding */
p = *out;
for (i = 0, tder = derlst; i < sk_ASN1_VALUE_num(sk); i++, tder++)
{
memcpy(p, tder->data, tder->length);
p += tder->length;
}
*out = p;
/* If do_sort is 2 then reorder the STACK */
if (do_sort == 2)
{
for (i = 0, tder = derlst; i < sk_ASN1_VALUE_num(sk);
i++, tder++)
(void)sk_ASN1_VALUE_set(sk, i, tder->field);
}
OPENSSL_free(derlst);
OPENSSL_free(tmpdat);
return 1;
}
static int asn1_i2d_ex_primitive(ASN1_VALUE **pval, unsigned char **out,
const ASN1_ITEM *it, int tag, int aclass)
{
int len;
int utype;
int usetag;
int ndef = 0;
utype = it->utype;
/* Get length of content octets and maybe find
* out the underlying type.
*/
len = asn1_ex_i2c(pval, NULL, &utype, it);
/* If SEQUENCE, SET or OTHER then header is
* included in pseudo content octets so don't
* include tag+length. We need to check here
* because the call to asn1_ex_i2c() could change
* utype.
*/
if ((utype == V_ASN1_SEQUENCE) || (utype == V_ASN1_SET) ||
(utype == V_ASN1_OTHER))
usetag = 0;
else usetag = 1;
/* -1 means omit type */
if (len == -1)
return 0;
/* -2 return is special meaning use ndef */
if (len == -2)
{
ndef = 2;
len = 0;
}
/* If not implicitly tagged get tag from underlying type */
if (tag == -1) tag = utype;
/* Output tag+length followed by content octets */
if (out)
{
if (usetag)
ASN1_put_object(out, ndef, len, tag, aclass);
asn1_ex_i2c(pval, *out, &utype, it);
if (ndef)
ASN1_put_eoc(out);
else
*out += len;
}
if (usetag)
return ASN1_object_size(ndef, len, tag);
return len;
}
/* Produce content octets from a structure */
int asn1_ex_i2c(ASN1_VALUE **pval, unsigned char *cout, int *putype,
const ASN1_ITEM *it)
{
ASN1_BOOLEAN *tbool = NULL;
ASN1_STRING *strtmp;
ASN1_OBJECT *otmp;
int utype;
unsigned char *cont, c;
int len;
const ASN1_PRIMITIVE_FUNCS *pf;
pf = it->funcs;
if (pf && pf->prim_i2c)
return pf->prim_i2c(pval, cout, putype, it);
/* Should type be omitted? */
if ((it->itype != ASN1_ITYPE_PRIMITIVE)
|| (it->utype != V_ASN1_BOOLEAN))
{
if (!*pval) return -1;
}
if (it->itype == ASN1_ITYPE_MSTRING)
{
/* If MSTRING type set the underlying type */
strtmp = (ASN1_STRING *)*pval;
utype = strtmp->type;
*putype = utype;
}
else if (it->utype == V_ASN1_ANY)
{
/* If ANY set type and pointer to value */
ASN1_TYPE *typ;
typ = (ASN1_TYPE *)*pval;
utype = typ->type;
*putype = utype;
pval = (ASN1_VALUE **)&typ->value.ptr;
}
else utype = *putype;
switch(utype)
{
case V_ASN1_OBJECT:
otmp = (ASN1_OBJECT *)*pval;
cont = otmp->data;
len = otmp->length;
break;
case V_ASN1_NULL:
cont = NULL;
len = 0;
break;
case V_ASN1_BOOLEAN:
tbool = (ASN1_BOOLEAN *)pval;
if (*tbool == -1)
return -1;
if (it->utype != V_ASN1_ANY)
{
/* Default handling if value == size field then omit */
if (*tbool && (it->size > 0))
return -1;
if (!*tbool && !it->size)
return -1;
}
c = (unsigned char)*tbool;
cont = &c;
len = 1;
break;
case V_ASN1_BIT_STRING:
return i2c_ASN1_BIT_STRING((ASN1_BIT_STRING *)*pval,
cout ? &cout : NULL);
break;
case V_ASN1_INTEGER:
case V_ASN1_NEG_INTEGER:
case V_ASN1_ENUMERATED:
case V_ASN1_NEG_ENUMERATED:
/* These are all have the same content format
* as ASN1_INTEGER
*/
return i2c_ASN1_INTEGER((ASN1_INTEGER *)*pval,
cout ? &cout : NULL);
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_SEQUENCE:
case V_ASN1_SET:
default:
/* All based on ASN1_STRING and handled the same */
strtmp = (ASN1_STRING *)*pval;
/* Special handling for NDEF */
if ((it->size == ASN1_TFLG_NDEF)
&& (strtmp->flags & ASN1_STRING_FLAG_NDEF))
{
if (cout)
{
strtmp->data = cout;
strtmp->length = 0;
}
/* Special return code */
return -2;
}
cont = strtmp->data;
len = strtmp->length;
break;
}
if (cout && len)
memcpy(cout, cont, len);
return len;
}
|
