* asn1buf.c (asn1buf_sync): Add new arguments to include the full

	complement of data about a prefetched tag, as well as to indicate
	whether the prefetched tag or the surrounding sequence is of an
	indefinite length.
	(asn1buf_skiptail): Add new arguments to indicate whether the
	prefetched tag is indefinite, as well as its length.  This
	facilitates proper skipping of trailing garbage.
	(asn1buf_remains): Add new argument to indicate whether the
	surrounding encoding is indefinite.  Don't advance buf->next if an
	EOC encoding is detected; the caller will do that.

	* asn1buf.h: Update prototypes.

	* asn1_get.c (asn1_get_tag_indef): Don't treat EOC encoding as
	special anymore, since previous behavior was overloading the
	tag number in a bad way.  Also, report a MISMATCH_INDEF error if
	the tag encoding is for the forbidden primitive constructed
	encoding.

	* asn1_k_decode.c (next_tag): Call get_tag_indef() in order to get
	information about whether the length is indefinite.  Don't check
	the tag class and construction explicitly.
	(get_eoc): New macro to get a tag and check if it is an EOC
	encoding.
	(get_field, opt_field): Move the check for the tag class and
	construction to here.
	(get_field_body, get_lenfield_body): Call get_eoc() instead of
	next_tag() if we are decoding a constructed indefinite encoding.
	(begin_structure): Use a different variable to indicate whether
	the sequence is indefinite as opposed to whether an individual
	field is indefinite.
	(end_structure): Update to new calling convention of
	asn1buf_sync().
	(sequence_of): Rewrite significantly.
	(sequence_of_common): Move the bulk of previous sequence_of()
	macro to here.  Does not declare some variables that sequence_of()
	declares.
	(sequence_of_no_tagvars): Similar to sequence_of() macro but
	declares different variables for the purpose of prefetching the
	final tag.
	(end_sequence_of_no_tagvars): Similar to end_sequence_of() macro
	but uses variables declared by the sequence_of_no_tagvars() macro
	to prefetch the final tag.
	(asn1_decode_principal_name): Update for new asn1buf_remains()
	calling convention.  Call sequence_of_no_tagvars(), etc. instead
	of sequence_of(), etc. in order to not declare shadowing
	block-local variables.
	(decode_array_body): Update for new asn1buf_remains() calling
	convention.
	(asn1_decode_sequence_of_enctype): Update for new
	asn1buf_remains() calling convention.

	* krb5_decode.c (next_tag): Call get_tag_indef() in order to get
	information about whether the length is indefinite.  Don't check
	the tag class and construction explicitly.
	(get_eoc): New macro to get a tag and check if it is an EOC
	encoding.
	(get_field, opt_field): Move the check for the tag class and
	construction to here.
	(get_field_body, get_lenfield_body): Call get_eoc() instead of
	next_tag() if we are decoding a constructed indefinite encoding.
	(begin_structure): Use a different variable to indicate whether
	the sequence is indefinite as opposed to whether an individual
	field is indefinite.
	(end_structure): Update to new calling convention of
	asn1buf_sync().

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@12816 dc483132-0cff-0310-8789-dd5450dbe970

1 files changed, 3 insertions, 7 deletions

diff --git a/src/lib/krb5/asn.1/asn1_get.c b/src/lib/krb5/asn.1/asn1_get.c
index b233a1a..fc945f1 100644
--- a/src/lib/krb5/asn.1/asn1_get.c
+++ b/src/lib/krb5/asn.1/asn1_get.c
@@ -42,17 +42,13 @@ asn1_get_tag_indef(buf, class, construction, tagnum, retlen, indef)
       *tagnum = ASN1_TAGNUM_CEILING;
       return 0;
   }
-  /* Allow for the indefinite encoding */
-  if ((buf->bound - buf->next + 1 >= 2)
-      && !*(buf->next) && !*(buf->next + 1)) {
-    buf->next += 2;
-    *tagnum = ASN1_TAGNUM_CEILING;
-    return 0;
-  }
   retval = asn1_get_id(buf,class,construction,tagnum);
   if(retval) return retval;
   retval = asn1_get_length(buf,retlen,indef);
   if(retval) return retval;
+  if (indef != NULL && *indef &&
+      construction != NULL && *construction != CONSTRUCTED)
+    return ASN1_MISMATCH_INDEF;
   return 0;
 }