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tasn_dec.c

/* tasn_dec.c */
/* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL
 * project 2000.
 */
/* ====================================================================
 * Copyright (c) 2000-2005 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(const unsigned char **in, long len);
static int asn1_find_end(const unsigned char **in, long len, char inf);

static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,
                        char inf, int tag, int aclass);

static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen);

static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass,
                        char *inf, char *cst,
                        const unsigned char **in, long len,
                        int exptag, int expclass, char opt,
                        ASN1_TLC *ctx);

static int asn1_template_ex_d2i(ASN1_VALUE **pval,
                        const unsigned char **in, long len,
                        const ASN1_TEMPLATE *tt, char opt,
                        ASN1_TLC *ctx);
static int asn1_template_noexp_d2i(ASN1_VALUE **val,
                        const unsigned char **in, long len,
                        const ASN1_TEMPLATE *tt, char opt,
                        ASN1_TLC *ctx);
static int asn1_d2i_ex_primitive(ASN1_VALUE **pval,
                        const unsigned char **in, long len,
                        const ASN1_ITEM *it,
                        int tag, int aclass, char opt, ASN1_TLC *ctx);

/* Table to convert tags to bit values, used for MSTRING type */
static const unsigned long tag2bit[32] = {
0,    0,    0,    B_ASN1_BIT_STRING,      /* tags  0 -  3 */
B_ASN1_OCTET_STRING,    0,    0,          B_ASN1_UNKNOWN,/* tags  4- 7 */
B_ASN1_UNKNOWN,   B_ASN1_UNKNOWN,   B_ASN1_UNKNOWN,   B_ASN1_UNKNOWN,/* tags  8-11 */
B_ASN1_UTF8STRING,B_ASN1_UNKNOWN,B_ASN1_UNKNOWN,B_ASN1_UNKNOWN,/* tags 12-15 */
B_ASN1_SEQUENCE,0,B_ASN1_NUMERICSTRING,B_ASN1_PRINTABLESTRING, /* tags 16-19 */
B_ASN1_T61STRING,B_ASN1_VIDEOTEXSTRING,B_ASN1_IA5STRING,       /* tags 20-22 */
B_ASN1_UTCTIME, B_ASN1_GENERALIZEDTIME,                      /* tags 23-24 */ 
B_ASN1_GRAPHICSTRING,B_ASN1_ISO64STRING,B_ASN1_GENERALSTRING,  /* tags 25-27 */
B_ASN1_UNIVERSALSTRING,B_ASN1_UNKNOWN,B_ASN1_BMPSTRING,B_ASN1_UNKNOWN, /* tags 28-31 */
      };

unsigned long ASN1_tag2bit(int tag)
      {
      if ((tag < 0) || (tag > 30)) return 0;
      return tag2bit[tag];
      }

/* 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,
            const unsigned char **in, long len, const ASN1_ITEM *it)
      {
      ASN1_TLC c;
      ASN1_VALUE *ptmpval = NULL;
      if (!pval)
            pval = &ptmpval;
      c.valid = 0;
      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,
            const unsigned char **in, long len, const ASN1_TEMPLATE *tt)
      {
      ASN1_TLC c;
      c.valid = 0;
      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, const 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;
      const unsigned char *p = NULL, *q;
      unsigned char *wp=NULL; /* BIG FAT WARNING!  BREAKS CONST WHERE USED */
      unsigned char 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)
                  {
                  wp = *(unsigned char **)in;
                  imphack = *wp;
                  if (p == NULL)
                        {
                        ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
                              ERR_R_NESTED_ASN1_ERROR);
                        goto err;
                        }
                  *wp = (unsigned char)((*p & V_ASN1_CONSTRUCTED)
                                                | it->utype);
                  }

            ptmpval = cf->asn1_d2i(pval, in, len);

            if (tag != -1)
                  *wp = 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 && !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_NDEF_SEQUENCE:
            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;
                  }
            /* If indefinite we don't do a length check */
            else seq_nolen = seq_eoc;
            if (!cst)
                  {
                  ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
                        ASN1_R_SEQUENCE_NOT_CONSTRUCTED);
                  goto err;
                  }

            if (!*pval && !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.
 */

static int asn1_template_ex_d2i(ASN1_VALUE **val,
                        const unsigned char **in, long inlen,
                        const ASN1_TEMPLATE *tt, char opt,
                                          ASN1_TLC *ctx)
      {
      int flags, aclass;
      int ret;
      long len;
      const 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_EX_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_EX_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,
                        const unsigned char **in, long len,
                        const ASN1_TEMPLATE *tt, char opt,
                        ASN1_TLC *ctx)
      {
      int flags, aclass;
      int ret;
      const 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_NOEXP_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_NOEXP_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_NOEXP_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_NOEXP_D2I,
                              ERR_R_NESTED_ASN1_ERROR);
                        goto err;
                        }
                  len -= p - q;
                  if (!sk_push((STACK *)*val, (char *)skfield))
                        {
                        ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
                                    ERR_R_MALLOC_FAILURE);
                        goto err;
                        }
                  }
            if (sk_eoc)
                  {
                  ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_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_NOEXP_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_NOEXP_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,
                        const 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;
      const unsigned char *p;
      BUF_MEM buf;
      const 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;
        ret = 0;
      /* 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_find_end(&p, plen, inf))
                         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))
                  {
                  free_cont = 1;
                  goto err;
                  }
            len = buf.length;
            /* Append a final null to string */
            if (!BUF_MEM_grow_clean(&buf, len + 1))
                  {
                  ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
                                    ERR_R_MALLOC_FAILURE);
                  return 0;
                  }
            buf.data[len] = 0;
            cont = (const 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, const unsigned char *cont, int len,
                  int utype, char *free_cont, const ASN1_ITEM *it)
      {
      ASN1_VALUE **opval = NULL;
      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();
                  if (typ == NULL)
                        goto err;
                  *pval = (ASN1_VALUE *)typ;
                  }
            else
                  typ = (ASN1_TYPE *)*pval;

            if (utype != typ->type)
                  ASN1_TYPE_set(typ, utype, NULL);
            opval = pval;
            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_EX_C2I,
                                    ASN1_R_NULL_IS_WRONG_LENGTH);
                  goto err;
                  }
            *pval = (ASN1_VALUE *)1;
            break;

            case V_ASN1_BOOLEAN:
            if (len != 1)
                  {
                  ASN1err(ASN1_F_ASN1_EX_C2I,
                                    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:
            if (utype == V_ASN1_BMPSTRING && (len & 1))
                  {
                  ASN1err(ASN1_F_ASN1_EX_C2I,
                              ASN1_R_BMPSTRING_IS_WRONG_LENGTH);
                  goto err;
                  }
            if (utype == V_ASN1_UNIVERSALSTRING && (len & 3))
                  {
                  ASN1err(ASN1_F_ASN1_EX_C2I,
                              ASN1_R_UNIVERSALSTRING_IS_WRONG_LENGTH);
                  goto err;
                  }
            /* All based on ASN1_STRING and handled the same */
            if (!*pval)
                  {
                  stmp = ASN1_STRING_type_new(utype);
                  if (!stmp)
                        {
                        ASN1err(ASN1_F_ASN1_EX_C2I,
                                          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 = (unsigned char *)cont; /* UGLY CAST! RL */
                  stmp->length = len;
                  *free_cont = 0;
                  }
            else
                  {
                  if (!ASN1_STRING_set(stmp, cont, len))
                        {
                        ASN1err(ASN1_F_ASN1_EX_C2I,
                                          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);
            if (opval)
                  *opval = NULL;
            }
      return ret;
      }


/* This function finds the end of an ASN1 structure when passed its maximum
 * length, whether it is indefinite length and a pointer to the content.
 * This is more efficient than calling asn1_collect because it does not
 * recurse on each indefinite length header.
 */

static int asn1_find_end(const unsigned char **in, long len, char inf)
      {
      int expected_eoc;
      long plen;
      const unsigned char *p = *in, *q;
      /* If not indefinite length constructed just add length */
      if (inf == 0)
            {
            *in += len;
            return 1;
            }
      expected_eoc = 1;
      /* Indefinite length constructed form. Find the end when enough EOCs
       * are found. If more indefinite length constructed headers
       * are encountered increment the expected eoc count otherwise just
       * skip to the end of the data.
       */
      while (len > 0)
            {
            if(asn1_check_eoc(&p, len))
                  {
                  expected_eoc--;
                  if (expected_eoc == 0)
                        break;
                  len -= 2;
                  continue;
                  }
            q = p;
            /* Just read in a header: only care about the length */
            if(!asn1_check_tlen(&plen, NULL, NULL, &inf, NULL, &p, len,
                        -1, 0, 0, NULL))
                  {
                  ASN1err(ASN1_F_ASN1_FIND_END, ERR_R_NESTED_ASN1_ERROR);
                  return 0;
                  }
            if (inf)
                  expected_eoc++;
            else
                  p += plen;
            len -= p - q;
            }
      if (expected_eoc)
            {
            ASN1err(ASN1_F_ASN1_FIND_END, ASN1_R_MISSING_EOC);
            return 0;
            }
      *in = p;
      return 1;
      }
/* 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.
 */

static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,
                        char inf, int tag, int aclass)
      {
      const 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)
                  {
#ifdef OPENSSL_ALLOW_NESTED_ASN1_STRINGS
                  if (!asn1_collect(buf, &p, plen, ininf, tag, aclass))
                        return 0;
#else
                  ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_NESTED_ASN1_STRING);
                  return 0;
#endif
                  }
            else if (plen && !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, const unsigned char **p, long plen)
      {
      int len;
      if (buf)
            {
            len = buf->length;
            if (!BUF_MEM_grow_clean(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(const unsigned char **in, long len)
      {
      const 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,
                        const unsigned char **in, long len,
                        int exptag, int expclass, char opt,
                        ASN1_TLC *ctx)
      {
      int i;
      int ptag, pclass;
      long plen;
      const 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, and no error, length +
                   * header can't exceed total amount of data available. 
                   */
                  if (!(i & 0x81) && ((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:
                   * 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:
             * 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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