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Wireshark-dev: Re: [Wireshark-dev] asn1_ctx_t introduced in more BER functions

Date: Wed, 23 May 2007 14:33:44 +0200
      Hi Anders,


I have done some tests (gsm_map,bssmap,camel,inap,gsm_ss),
and I see a problem in gsm_ss_dissect
(asn1/gsm_ss/packet-gsm_ss-template.c)
To decode an USSD string, you have to give the actx pointer, when you call
the decoding function (as this is done in Notify SS).
Else, there is a crash, during the BER decoding, because we access to
actx->pinfo.

I suppose there is the same problem with other functions like
"lcs-AreaEventCancellation etc..", because we will try to access
actx->pinfo during the BER decoding. So, in any case, it is safer to give a
valid pointer to the asn1 context.

Regards
Florent
<<
int gsm_ss_dissect(tvbuff_t *tvb, proto_tree *tree, int offset, asn1_ctx_t
*actx, guint32 opcode, gint comp_type_tag)
{
      switch (comp_type_tag){
            case 1: /* invoke */
../..
                        case 16: /*Notify SS */
                              offset = dissect_notifySS(tree, tvb, offset,
actx);
                              break;
../..
                        case 19: /*Process Unstructured SS Data */
                              offset =
dissect_processUnstructuredSS_Data(tree, tvb, offset, actx);
                              break;
../..
                        case 112: /*lcs-AreaEventCancellation */
                              offset =
dissect_lcs_AreaEventCancellation(tree, tvb, offset,NULL /* axtx */);
                              break;
}




                                                                                                                                
                      "Anders Broman"                                                                                           
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                      reshark.org                      Subject: [Wireshark-dev] asn1_ctx_t introduced in more BER functions     
                                                                                                                                
                                                                                                                                
                      13/05/2007 23:03                                                                                          
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Hi,
asn1_ctx_t has been introduced in more BER functions as this affects many
dissectors something may have
been broken. If you have BER encoded traces please do some regression
tests.
Regards
Anders_______________________________________________
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