Re: LDL Driver: cannot send to arbitrary LLC (802.2) DSAP

I have been using the transparent mode in order to avoid this kind of 
thing.  My driver does its own filtering of addresses and SAPs.
-- Dave

At 09:33 AM 9/16/2004, Tim Brown wrote:
>I am porting some network multiplexor software which uses multiplexes
>messages between hosts and processes on hosts using 802.2 DSAP/SSAP
>addressing.
>
>I bind onto a DSAP, allowing me to listen for Ethernet frames addressed
>to me. Within those packets is the return address for me to send my replies
>to. This may or may not be the Ethernet address of the sender.
>
>I then wish to send a frame to the destination which may have an arbitrary
>DSAP. However, in eth_8022_mkhdr() in drivers/str/linux/ldl.c line:1704
>
>         if (dsap != dl->sap->sap.sap[0]) {
>                 struct sap *sap;
>
>                 for (sap = dl->subs; sap; sap = sap->next_sap)
>                         if (dsap == sap->sap.sap[0])
>                                 break;
>                 if (sap == NULL)
>                         return 0;
>         }
>
>i.e. if you are not bound to "dsap", or have an additional binding
>      to "dsap", then the message isn't sent.
>
>I am using LiS 2.17.U.
>
>I don't believe this behaviour is correct, since it is inconsistent
>with the Solaris and AIX DLPI drivers, as well as the understanding
>of most people here of how DSAP/SSAP addressing works; i.e. you bind
>onto and listen on a DSAP (or multiple DSAPs), but any process on any
>station can transmit to any of the available SSAPs.
>
>Therefore, I don't believe there is any reason for this code. Is there?
>
>Regards,
>
>Tim
>
>--
>Tim Brown <[email protected]> |            City Computing Limited |
>T: +44 20 8770 2110               |      City House, Sutton Park Road |
>F: +44 20 8770 2130               |       Sutton, Surrey, SM1 2AE, GB |
>BEAUTY: What's in your eye when you have a bee in your hand.__________/
>
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