site_archiver@lists.apple.com Delivered-To: darwin-dev@lists.apple.com Ryan On Jun 3, 2007, at 9:36 PM, Erez Kaplan wrote: Ryan, I have full code control over "my userland application". Erez On Jun 3, 2007, at 11:30 PM, Ryan McGann wrote: HOWEVER - I am unable to obtain the local address at this point. I have used err = sock_getsockname(so, (struct sockaddr *) &local, (int)&len); but I keep getting <0.0.0.0> as a result. Erez, Ryan _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.appl... The way this is usually performed is to use a sysctl or a kern_ctl socket that connects to your kernel extension. If you are unfamiliar with kern_ctl sockets, in userspace they work just like regular sockets; you create them like socket( AF_INET, SOCK_DGRAM, SYSPROTO_CONTROL ); You can then write data to them, or simply call setsockopt() on it to communicate with your kernel extension. We implemented a special setsockopt that tells our kernel extension the userland process ID; e.g. pid_t thePID = getpid(); setsockopt( kernsock, SYSPROTO_CONTROL, kSetControllerProcessID, &thePID, sizeof( thePID ) ); In your kernel extension you can determine the process ID of the process that is making the connect() using proc_selfpid(). If the process ID returned by proc_selfpid is your userland process ID, then you can ignore the connect() request. Alternatively, you can send the local port number down using the setsockopt. My NKE kext needs to ignore redirection if request is from "my userland application". i.e redirect all applications accept mine. optionally is there another call back where I can examine both addresses and change the <to> prior to bind? The problem is that the kernel performs an implicit bind when the socket is connected if no local name is assigned to the socket already. Your NKE connect_out callback is being called when the client application calls connect() (inside the syscall basically), so unless the client application performs a bind() first (which is rarely done for outbound connects) the socket will not have a local address assigned to it. The kernel will assign one later during the actual connect. You can obtain the local address later inside of sf_notify, when you get a notification that the socket has gone into the connected state, but not before (as far as I know). In short, there is no way to both redirect the socket (which can only be done in the connect_out callback) and use the source ip:port. Can you explain why you need the source ip:port? This email sent to site_archiver@lists.apple.com