site_archiver@lists.apple.com Delivered-To: darwin-kernel@lists.apple.com Hey mm Best regards, Platon On Aug 24, 2007, at 7:54 PM, mm w wrote: Hi Platon, If your modifications involve changes to packet header information you must swallow the packet entirely and reinject it. Cheers Hi Everybody It seems I can't figure how to correctly offload my TCP/UDP packet to the H/W network checksumming routines. It seems rather inconvenient that I have to add all typical checksumming code into the driver - because neither of mbuf API can actually re-checksum the packet. As for H/W support - I can see from the flags that my H/W supports TCP offload but if I set tcp checksum f.ex. to zero in my Interface filter the packet will not be checksummed later in the hardware. Thus some questions: 1) Seems that there is no kernel API to do IP checksumming in Mac - is it true, if not how to do it? mbuf finalize func does not do it. 2) Seems that hardware TCP/UDP checksum offload is actually missing from Mac at all? At least it is not present on MacBook/MacBook pro. If yes why does it advertise itself using ifnet API as capable to do it? If I am wrong how can I check that my network adapter is actually doing its work and how can I benefit from this in my code (I am actively changing the packet) Best regards, Platon. On Aug 23, 2007, at 9:05 AM, JanakiRam wrote: openspecies%40gmail.com This email sent to openspecies@gmail.com _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.a... Yup exactly, that's what is written in Apple's docs but as we all have access to the kernel and overall - why on earth we should need to do this? Of course there are cases - when I change destination, metric, etc, etc. But if f.ex. I just changed packet length? Imho it's not the case for re-injection. And it actually works as expected on my test-cases - I can do whatever I want as long as I keep its destination, etc. But my case is simple I need to increase data size for say 20 bytes. I actually managed to get some weird checksum (wrong) from H/w - I will keep you informed about my progress.. On 8/24/07, Platon Fomichev <pfomichev@alarity.com> wrote: This email sent to site_archiver@lists.apple.com