func (s *AfpacketSniffer) Open(config *Config) error {
// Capture settings
const (
// MMap buffer size
buffer_mb int = 24
// Max packet length
snaplen int = 65536
// Set the interface in promiscuous mode
promisc bool = true
)
frame_size, block_size, num_blocks, err := afpacketComputeSize(
buffer_mb,
snaplen,
os.Getpagesize())
if err != nil {
return fmt.Errorf("Error calculating afpacket size: %s", err)
}
// Configure the afpacket ring and bind it to the interface
var tPacket *afpacket.TPacket
tPacket, err = afpacket.NewTPacket(
afpacket.OptInterface(*iface),
afpacket.OptFrameSize(frame_size),
afpacket.OptBlockSize(block_size),
afpacket.OptNumBlocks(num_blocks))
if err != nil {
fmt.Errorf("Error opening afpacket interface: %s", err)
}
s.handle = tPacket
return nil
}
func NewAFPacketHandle(ifName string, snaplen int32) (*AFPacketHandle, error) {
tpacket, err := afpacket.NewTPacket(
afpacket.OptInterface(ifName),
afpacket.OptFrameSize(snaplen),
)
if err != nil {
return nil, err
}
return &AFPacketHandle{tpacket: tpacket}, err
}