wireshark/epan/dissectors/asn1/spnego/spnego.cnf

# spnego.cnf
# spnego conformation file

#.EXPORTS

#.PDU

#.NO_EMIT ONLY_VALS
NegotiationToken

#.FN_BODY NegotiationToken/negTokenInit
  gboolean is_response = actx->pinfo->ptype == PT_TCP &&
                         actx->pinfo->srcport < 1024;

  /*
   * We decode as negTokenInit2 or negTokenInit depending on whether or not
   * we are in a response or a request. That is essentially what MS-SPNG
   * says.
   */
  if (is_response) {
    return dissect_spnego_NegTokenInit2(%(IMPLICIT_TAG)s, %(TVB)s, %(OFFSET)s,
                                        %(ACTX)s, %(TREE)s, %(HF_INDEX)s);
  } else {
    return dissect_spnego_NegTokenInit(%(IMPLICIT_TAG)s, %(TVB)s, %(OFFSET)s,
                                       %(ACTX)s, %(TREE)s, %(HF_INDEX)s);
  }

#.FN_PARS MechType

  FN_VARIANT = _str  VAL_PTR = &MechType_oid

#.FN_BODY MechType

  gssapi_oid_value *value;

%(DEFAULT_BODY)s

  value = gssapi_lookup_oid_str(MechType_oid);

  /*
   * Tell our caller the first mechanism we see, so that if
   * this is a negTokenInit with a mechToken, it can interpret
   * the mechToken according to the first mechType.  (There
   * might not have been any indication of the mechType
   * in prior frames, so we can't necessarily use the
   * mechanism from the conversation; i.e., a negTokenInit
   * can contain the initial security token for the desired
   * mechanism of the initiator - that's the first mechanism
   * in the list.)
   */
  if (!saw_mechanism) {
    if (value)
      next_level_value = value;
    saw_mechanism = TRUE;
  }

#.FN_BODY InnerContextToken

  gssapi_oid_value *next_level_value_lcl;
  proto_item *item;
  proto_tree *subtree;
  tvbuff_t *token_tvb;
  int len;

  /*
   * XXX - what should we do if this OID doesn't match the value
   * attached to the frame or conversation?  (That would be
   * bogus, but that's not impossible - some broken implementation
   * might negotiate some security mechanism but put the OID
   * for some other security mechanism in GSS_Wrap tokens.)
   * Does it matter?
   */
  next_level_value_lcl = gssapi_lookup_oid_str(MechType_oid);

  /*
   * Now dissect the GSS_Wrap token; it's assumed to be in the
   * rest of the tvbuff.
   */
  item = proto_tree_add_item(tree, hf_spnego_wraptoken, tvb, offset, -1, ENC_NA);

  subtree = proto_item_add_subtree(item, ett_spnego_wraptoken);

  /*
   * Now, we should be able to dispatch after creating a new TVB.
   * The subdissector must return the length of the part of the
   * token it dissected, so we can return the length of the part
   * we (and it) dissected.
   */
  token_tvb = tvb_new_subset_remaining(tvb, offset);
  if (next_level_value_lcl && next_level_value_lcl->wrap_handle) {
    len = call_dissector(next_level_value_lcl->wrap_handle, token_tvb, actx->pinfo,
                         subtree);
    if (len == 0)
      offset = tvb_reported_length(tvb);
    else
      offset = offset + len;
  } else
    offset = tvb_reported_length(tvb);

#.FN_BODY MechTypeList

  conversation_t *conversation;

  saw_mechanism = FALSE;

%(DEFAULT_BODY)s

  /*
   * If we saw a mechType we need to store it in case the negTokenTarg
   * does not provide a supportedMech.
   */
  if(saw_mechanism){
    conversation = find_or_create_conversation(actx->pinfo);
    conversation_add_proto_data(conversation, proto_spnego, next_level_value);
  }

#.FN_PARS NegTokenInit/mechToken

  VAL_PTR = &mechToken_tvb

#.FN_BODY NegTokenInit/mechToken

  tvbuff_t *mechToken_tvb = NULL;

%(DEFAULT_BODY)s

  /*
   * 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 (mechToken_tvb && next_level_value)
     call_dissector(next_level_value->handle, mechToken_tvb, actx->pinfo, tree);

#.FN_BODY NegTokenTarg/supportedMech

  conversation_t *conversation;

  saw_mechanism = FALSE;

%(DEFAULT_BODY)s

  /*
   * If we saw an explicit mechType we store this in the conversation so that
   * it will override any mechType we might have picked up from the
   * negTokenInit.
   */
  if(saw_mechanism){
    conversation = find_or_create_conversation(actx->pinfo);
    conversation_add_proto_data(conversation, proto_spnego, next_level_value);
  }


#.FN_PARS NegTokenTarg/responseToken

  VAL_PTR = &responseToken_tvb

#.FN_BODY NegTokenTarg/responseToken

  tvbuff_t *responseToken_tvb;


%(DEFAULT_BODY)s


  /*
   * 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 (responseToken_tvb && (tvb_reported_length(responseToken_tvb) > 0) ){
    gssapi_oid_value *value=next_level_value;

    if(value){
      call_dissector(value->handle, responseToken_tvb, actx->pinfo, tree);
    }
  }


#.FN_BODY NegTokenTarg/mechListMIC VAL_PTR = &mechListMIC_tvb

  tvbuff_t *mechListMIC_tvb;


%(DEFAULT_BODY)s


  /*
   * 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 (mechListMIC_tvb && (tvb_reported_length(mechListMIC_tvb) > 0) ){
    gssapi_oid_value *value=next_level_value;

    if(value){
      call_dissector(value->handle, mechListMIC_tvb, actx->pinfo, tree);
    }
  }

#.END

#
# Editor modelines  -  https://www.wireshark.org/tools/modelines.html
#
# Local variables:
# c-basic-offset: 2
# tab-width: 8
# indent-tabs-mode: nil
# End:
#
# vi: set shiftwidth=2 tabstop=8 expandtab:
# :indentSize=2:tabSize=8:noTabs=true:
#