dissect_ber_octet_string() can return a null tvbuff pointer, if the

putative octet string isn't one; always check before using it to
dissect, and don't call the dissector if the tvbuff is null.  This
should fix bug 472.

svn path=/trunk/; revision=15946

1 files changed, 11 insertions, 12 deletions

diff --git a/asn1/spnego/spnego.cnf b/asn1/spnego/spnego.cnf
index b57161c310..1ebd727d5e 100644
--- a/asn1/spnego/spnego.cnf
+++ b/asn1/spnego/spnego.cnf
@@ -101,14 +101,11 @@ NegTokenInit/mechListMIC negTokenInit_mechListMIC
 
 %(DEFAULT_BODY)s
 
-  if (! mechToken_tvb) {
-    THROW(ReportedBoundsError);
-  }
-
   /*
-   * Now, we should be able to dispatch after creating a new TVB.
+   * Now, we should be able to dispatch, if we've gotten a tvbuff for
+   * the token and we have information on how to dissect its contents.
    */
-  if (next_level_value)
+  if (mechToken_tvb && next_level_value)
      call_dissector(next_level_value->handle, mechToken_tvb, pinfo, tree);
 
 
@@ -145,7 +142,7 @@ NegTokenInit/mechListMIC negTokenInit_mechListMIC
     /*
      * Now, we should be able to dispatch with that tvbuff.
      */
-    if (next_level_value)
+    if (mechListMIC_tvb && next_level_value)
       call_dissector(next_level_value->handle, mechListMIC_tvb, pinfo, tree);
     return offset;
   }
@@ -187,12 +184,13 @@ NegTokenInit/mechListMIC negTokenInit_mechListMIC
 
 
   /*
-   * Now, we should be able to dispatch with that tvbuff.
+   * Now, we should be able to dispatch, if we've gotten a tvbuff for
+   * the token and we have information on how to dissect its contents.
    * However, we should make sure that there is something in the 
    * response token ...
    */
-  if (tvb_reported_length(responseToken_tvb) > 0) {
-    if (next_level_value)
+  if (responseToken_tvb && next_level_value) {
+    if (tvb_reported_length(responseToken_tvb) > 0)
       call_dissector(next_level_value->handle, responseToken_tvb, pinfo, tree);
   }
 
@@ -210,9 +208,10 @@ NegTokenInit/mechListMIC negTokenInit_mechListMIC
 
 
   /*
-   * Now, we should be able to dispatch with that tvbuff.
+   * Now, we should be able to dispatch, if we've gotten a tvbuff for
+   * the MIC and we have information on how to dissect its contents.
    */
-  if (next_level_value)
+  if (mechListMIC_tvb && next_level_value)
     call_dissector(next_level_value->handle, mechListMIC_tvb, pinfo, tree);