Free up ADB and CHOICE if already initialised.
[openssl.git] / crypto / asn1 / tasn_dec.c
index 2b9c256..7fd336a 100644 (file)
@@ -1,6 +1,7 @@
 /* tasn_dec.c */
-/* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL
- * project 2000.
+/*
+ * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project
+ * 2000.
  */
 /* ====================================================================
  * Copyright (c) 2000-2005 The OpenSSL Project.  All rights reserved.
@@ -10,7 +11,7 @@
  * are met:
  *
  * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer. 
+ *    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
@@ -56,7 +57,6 @@
  *
  */
 
-
 #include <stddef.h>
 #include <string.h>
 #include <openssl/asn1.h>
@@ -69,1242 +69,1160 @@ 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);
+                        char inf, int tag, int aclass, int depth);
 
 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);
+                           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);
+                                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);
+                                   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);
+                                 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 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 */
-0,     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 */
-       };
+static const unsigned long tag2bit[32] = {
+    /* tags  0 -  3 */
+    0, 0, 0, B_ASN1_BIT_STRING,
+    /* tags  4- 7 */
+    B_ASN1_OCTET_STRING, 0, 0, B_ASN1_UNKNOWN,
+    /* tags  8-11 */
+    B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN,
+    /* tags 12-15 */
+    B_ASN1_UTF8STRING, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN,
+    /* tags 16-19 */
+    B_ASN1_SEQUENCE, 0, B_ASN1_NUMERICSTRING, B_ASN1_PRINTABLESTRING,
+    /* tags 20-22 */
+    B_ASN1_T61STRING, B_ASN1_VIDEOTEXSTRING, B_ASN1_IA5STRING,
+    /* tags 23-24 */
+    B_ASN1_UTCTIME, B_ASN1_GENERALIZEDTIME,
+    /* tags 25-27 */
+    B_ASN1_GRAPHICSTRING, B_ASN1_ISO64STRING, B_ASN1_GENERALSTRING,
+    /* tags 28-31 */
+    B_ASN1_UNIVERSALSTRING, B_ASN1_UNKNOWN, B_ASN1_BMPSTRING, B_ASN1_UNKNOWN,
+};
 
 unsigned long ASN1_tag2bit(int tag)
-       {
-       if ((tag < 0) || (tag > 30)) return 0;
-       return tag2bit[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
+#define asn1_tlc_clear(c)       if (c) (c)->valid = 0
+/* Version to avoid compiler warning about 'c' always non-NULL */
+#define asn1_tlc_clear_nc(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.
+/*
+ * 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;
-       asn1_tlc_clear(&c);
-       if (ASN1_item_ex_d2i(pval, in, len, it, -1, 0, 0, &c) > 0) 
-               return *pval;
-       return NULL;
-       }
+                          const unsigned char **in, long len,
+                          const ASN1_ITEM *it)
+{
+    ASN1_TLC c;
+    ASN1_VALUE *ptmpval = NULL;
+    if (!pval)
+        pval = &ptmpval;
+    asn1_tlc_clear_nc(&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,
-               const 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
+                      const unsigned char **in, long len,
+                      const ASN1_TEMPLATE *tt)
+{
+    ASN1_TLC c;
+    asn1_tlc_clear_nc(&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, 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, *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;
-                       *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.
+                     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 **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, NULL))
+            goto auxerr;
+        if (*pval) {
+            /* Free up and zero CHOICE value if initialised */
+            i = asn1_get_choice_selector(pval, it);
+            if ((i >= 0) && (i < it->tcount)) {
+                tt = it->templates + i;
+                pchptr = asn1_get_field_ptr(pval, tt);
+                ASN1_template_free(pchptr, tt);
+                asn1_set_choice_selector(pval, -1, it);
+            }
+        } else 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 */
+        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, NULL))
+            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, NULL))
+            goto auxerr;
+
+        /* Free up and zero any ADB found */
+        for (i = 0, tt = it->templates; i < it->tcount; i++, tt++) {
+            if (tt->flags & ASN1_TFLG_ADB_MASK) {
+                const ASN1_TEMPLATE *seqtt;
+                ASN1_VALUE **pseqval;
+                seqtt = asn1_do_adb(pval, tt, 1);
+                pseqval = asn1_get_field_ptr(pval, seqtt);
+                ASN1_template_free(pseqval, seqtt);
+            }
+        }
+
+        /* 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, NULL))
+            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;
-       }
+                                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);
+    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;
-       }
+                                   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_OF(ASN1_VALUE) *sktmp = (STACK_OF(ASN1_VALUE) *)*val;
+            ASN1_VALUE *vtmp;
+            while (sk_ASN1_VALUE_num(sktmp) > 0) {
+                vtmp = sk_ASN1_VALUE_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_ASN1_VALUE_push((STACK_OF(ASN1_VALUE) *)*val, 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);
+    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;
-       /* 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))
-                       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;
-       }
+                                 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) {
+        if (utype == V_ASN1_NULL || utype == V_ASN1_BOOLEAN
+            || utype == V_ASN1_OBJECT || utype == V_ASN1_INTEGER
+            || utype == V_ASN1_ENUMERATED) {
+            ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_TYPE_NOT_PRIMITIVE);
+            return 0;
+        }
+        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, 0)) {
+            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();
-                       *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:
-               /* 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.
+                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 = &typ->value.asn1_value;
+    }
+    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.
+{
+    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;
+#ifndef ASN1_MAX_STRING_NEST
+/*
+ * This determines how many levels of recursion are permitted in ASN1 string
+ * types. If it is not limited stack overflows can occur. If set to zero no
+ * recursion is allowed at all. Although zero should be adequate examples
+ * exist that require a value of 1. So 5 should be more than enough.
+ */
+# define ASN1_MAX_STRING_NEST 5
 #endif
-                       }
-               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 asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,
+                        char inf, int tag, int aclass, int depth)
+{
+    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) {
+            if (depth >= ASN1_MAX_STRING_NEST) {
+                ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_NESTED_ASN1_STRING);
+                return 0;
+            }
+            if (!asn1_collect(buf, &p, plen, ininf, tag, aclass, depth + 1))
+                return 0;
+        } 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;
-       }
+{
+    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.
+{
+    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;
-       }
+                           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;
+}