Hi Michael I do suspect my bad English made my request unclear, my apologies for that. Let me clarify.
basically I don"t care of the payload of the frame. What I am trying to do is to have a program running locally to be able to take a valid frame -from somewhere - and inject into the local OS, as it was received -from the "outside" by one interface. The content of the ethernet frame itself (being IPv4, or others) is not that relevant for me: the frame existed before on another machine, and it was a valid frame already. I am able to read into it, and check the frame on the destination machine is the same, so I don't need to analyse. The problem I am facing, I suspect, is that a Read() io.ReadWriter is reading on the same interface, selecting all the frames with the tap device as a destination. So when I write my frame into the interface, this Read() is intercepting it. since this Read() is blocking, I cannot use a go mutex to make it work only when the writer is not using the io.ReadWriter (Read() would take all the time) , so the problem is, this library cannot be used for duplex communications: if you use the Read() method, then you will not be able to do Write(), because the read will not allow the frame to go into the interface normally.... On Saturday, 17 June 2017 18:01:10 UTC+2, Michael Jones wrote: > > Sorry to say that I don't have a direct answer for you. > > However, I happen to be doing some packet analysis at the moment--focused > first in the analysis part--and have recently started looking for helpful > frameworks/libraries into which my code can be embedded. What I found so > far is: > > https://github.com/google/gopacket > > > though there may be more to choose from as a starting point. Maybe this > will meet your needs. Maybe someone else can advise both is us! > > Michael > > On Sat, Jun 17, 2017 at 8:32 AM, <fusi.enr...@gmail.com <javascript:>> > wrote: > >> Hi All >> >> anyone knows how to write an ethernet frame into a device, in a way the >> operating system thinks is to be received? >> >> Let me explain the issue: >> >> I am writing a software (for Linux only) which creates a tap device on >> machine A, reads the frames, encrypts and sends them via the network to the >> same software, listening on machine B , which writes the frame on its own >> tap device . >> Until reading the frame, sending, encrypting , receiving and decrypting, >> everything goes. >> >> (I'm using https://github.com/songgao/water , if you know something >> better, it would be WAY appreciated ) >> >> So the machine B reads the payload, does its job, and now I have a lovely >> ethernet frame, stored into a []byte variable. >> >> The next problem is now to write it to the operating system, in a way >> that the operating system behaves like it was received from the outside. >> >> I tried to use the "Write()" method implemented with the water library, >> but it simply doesn't works. >> >> What happens now is that , into this library the operation of write() is >> behaving as the frame was entering the device from the operating system, >> and not FOR the operating system, resulting the >> Read() thread to capture the frame again. >> >> So , my question is: >> >> anyone knows a library, or a way, to inject an ethernet frame into the OS >> as it was received from "outside"? >> >> >> many thanks. >> >> FEM >> >> -- >> You received this message because you are subscribed to the Google Groups >> "golang-nuts" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to golang-nuts...@googlegroups.com <javascript:>. >> For more options, visit https://groups.google.com/d/optout. >> > > > > -- > Michael T. Jones > michae...@gmail.com <javascript:> > -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
