site_archiver@lists.apple.com Delivered-To: darwin-kernel@lists.apple.com Gentlemen, good day to you. Best regards, Stauff__ _______________________________________________ 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... I am creating a port of a Win32 NDIS intermediate driver. The main task I am currently working on is bytes reservation. Consider the following task - I need to reserve some bytes in every packet - even when it's filled up to MTU so I can insert additional special bytes from the driver. In Windows I do so by changing MTU for all upper layer drivers so they see driver MTU minus let's say 28 bytes which I grab for myself. I need to solve the same task on Mac, however I see that there is no special means to switch MTU per-layer but only globally. However still I need somehow to force all upper NKE's and stack to believe that MTU is 28 bytes less but network card driver itself should treat such packets as O.K. I will dig into the kernel but may be there is a known way to do so. Thanks in advance. Just in case NKE I am working on is an interface filter - I need to work on packets after fragmentation and I need to access link layer info. This email sent to site_archiver@lists.apple.com