2008/12/18 Iñaki Baz Castillo <[email protected]>: > The call hasn't finished, but OpenSIPS has ended the accounting for > this call since it received a BYE. And this BYE will generate a > correct ACC Stop action (since it matches From_tag, To_tag and > Call-ID). > > I think this is *VERY* dangerous and I hope I'm wrong. > > Would help the dialog module here? does the dialog module check the > CSeq of the BYE in some way and could it prevent OpenSIPS from > generating the ACC STOP action? (I don't think so).
I've also asked in SIP-implementors and an idea could be generating the ACC STOP action when receiving the 200 OK for the BYE (and not when receiving the BYE itself). Of course this will be valid when the gateway is the recipient of the BYE (and we know the gateway is not an "attacker"), but this is not valid when the recipient of the BYE is an user since it could send no reply for the BYE. The only solution I see is: - Using the dialog module, OpenSIPS should check if the CSeq value in the BYE. 1) OpenSIPs should forward the BYE just in case the CSeq is higher than the actual CSeq for this dialog direction. 2) OpenSIPs should generate the ACC STOP action just in case the CSeq is higher than the actual CSeq for this dialog direction. Both 1) and 2) are needed since a gateway could accept a BYE with wrong CSeq. In this case the call is ended but the accounting STOP action doesn't exist (infinite call). But I think this is too complex, isn't it? -- Iñaki Baz Castillo <[email protected]> _______________________________________________ Users mailing list [email protected] http://lists.opensips.org/cgi-bin/mailman/listinfo/users
