* asn1_k_decode.c (asn1_decode_krb5_flags): Modify to deal with

	BIT STRING values that are not exactly 32 bits.  Throw away bits
	beyond number 31 in a bit string for now.  Deal with masking out
	unused bits.

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@11055 dc483132-0cff-0310-8789-dd5450dbe970

diff --git a/src/lib/krb5/asn.1/ChangeLog b/src/lib/krb5/asn.1/ChangeLog
index ca3f679f504395501bee65fabe2e28b5cda8bfe8..a3d98ad5f2841b0001d3fa488fe84e42a18787b0 100644 (file)
--- a/src/lib/krb5/asn.1/ChangeLog
+++ b/src/lib/krb5/asn.1/ChangeLog
@@ -1,3 +1,10 @@
+Thu Dec  3 19:41:06 1998  Tom Yu  <tlyu@mit.edu>
+
+       * asn1_k_decode.c (asn1_decode_krb5_flags): Modify to deal with
+       BIT STRING values that are not exactly 32 bits.  Throw away bits
+       beyond number 31 in a bit string for now.  Deal with masking out
+       unused bits.
+
 1998-10-27  Marc Horowitz  <marc@mit.edu>
 
        * asn1buf.c (asn1buf_sync): interoperation testing against heimdal

diff --git a/src/lib/krb5/asn.1/asn1_k_decode.c b/src/lib/krb5/asn.1/asn1_k_decode.c
index 475bc0677a2d5ad0e844e7671d0f7ee669a49465..226b0443de0ac146e41669fda7edcf623f2d4f32 100644 (file)
--- a/src/lib/krb5/asn.1/asn1_k_decode.c
+++ b/src/lib/krb5/asn.1/asn1_k_decode.c
@@ -272,7 +272,7 @@ asn1_error_code asn1_decode_krb5_flags(buf, val)
      krb5_flags * val;
 {
   setup();
-  asn1_octet o;
+  asn1_octet unused, o;
   int i;
   krb5_flags f=0;
   unused_var(taglen);
@@ -281,16 +281,24 @@ asn1_error_code asn1_decode_krb5_flags(buf, val)
   if(retval) return retval;
   if(class != UNIVERSAL || construction != PRIMITIVE ||
      tagnum != ASN1_BITSTRING) return ASN1_BAD_ID;
-  if(length != 5) return ASN1_BAD_LENGTH;
 
-  retval = asn1buf_remove_octet(buf,&o); /* # of padding bits */
-  if(retval) return retval;    /*  should be 0 */
-  if(o != 0) return ASN1_BAD_FORMAT;
+  retval = asn1buf_remove_octet(buf,&unused); /* # of padding bits */
+  if(retval) return retval;
+
+  /* Number of unused bits must be between 0 and 7. */
+  if (unused > 7) return ASN1_BAD_FORMAT;
+  length--;
 
-  for(i=0; i<4; i++){
+  for(i = 0; i < length; i++) {
     retval = asn1buf_remove_octet(buf,&o);
     if(retval) return retval;
-    f = (f<<8) | ((krb5_flags)o&0xFF);
+    /* ignore bits past number 31 */
+    if (i < 4)
+      f = (f<<8) | ((krb5_flags)o&0xFF);
+  }
+  if (length <= 4) {
+    /* Mask out unused bits, but only if necessary. */
+    f &= ~0 << unused;
   }
   *val = f;
   return 0;