ZSocket is a library that wraps the linux zero-copy socket syscall to create a ring buffer in a memory mapped file. It also contains some utility functions and types to help with a handful of layer 2, 3, and 4 types. It is a lot like libcap, except it has easy to understand facilities for writing (injecting packets) to an interface.
ZSocket doesn't contain or wrap any C/C++, and it is lock free and thread safe.
The following program prints out all know layer types to ZSocket on a given interface:
package main
import (
"fmt"
"github.com/newtools/zsocket"
"github.com/newtools/zsocket/nettypes"
)
func main() {
// args: interfaceIndex, options, maxFrameSize, and maxTotalFrames
// inerfaceIndex: the index of the net device you want to open a raw socket to
// options: RX and TX, or just one or the other?
// maxFrameSize: must be a power of 2, bigger than zsocket.MinimumFrameSize,
// and smaller than maximum frame size
// maxTotalFrames: must be at least 16, and be a multiple of 8.
zs, err := zsocket.NewZSocket(14, zsocket.EnableRX, 2048, 64, nettypes.All)
// the above will result in a ring buffer of 64 frames at
// (2048 - zsocket.PacketOffset()) *writeable* bytes each
// for a total of 2048*64 bytes of *unswappable* system memory consumed.
if err != nil {
panic(err)
}
zs.Listen(func(f *nettypes.Frame, frameLen, capturedLen uint16) {
fmt.Printf(f.String(capturedLen, 0))
})
}-
See the examples folder for more simple programs that do various things with ZSocket.
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Learn how to set up a docker container with a custom veth-pair in the utils folder (useful for setting up complex virtual networking scenarios)
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Play around with FakeInterface to (and its examples folder) to play around with networking protocols.