61 lines
1.1 KiB
Go
61 lines
1.1 KiB
Go
package smux
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import (
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"encoding/binary"
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"fmt"
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)
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const (
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version = 1
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)
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const ( // cmds
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cmdSYN byte = iota // stream open
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cmdFIN // stream close, a.k.a EOF mark
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cmdPSH // data push
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cmdNOP // no operation
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)
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const (
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sizeOfVer = 1
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sizeOfCmd = 1
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sizeOfLength = 2
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sizeOfSid = 4
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headerSize = sizeOfVer + sizeOfCmd + sizeOfSid + sizeOfLength
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)
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// Frame defines a packet from or to be multiplexed into a single connection
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type Frame struct {
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ver byte
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cmd byte
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sid uint32
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data []byte
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}
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func newFrame(cmd byte, sid uint32) Frame {
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return Frame{ver: version, cmd: cmd, sid: sid}
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}
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type rawHeader []byte
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func (h rawHeader) Version() byte {
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return h[0]
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}
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func (h rawHeader) Cmd() byte {
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return h[1]
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}
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func (h rawHeader) Length() uint16 {
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return binary.LittleEndian.Uint16(h[2:])
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}
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func (h rawHeader) StreamID() uint32 {
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return binary.LittleEndian.Uint32(h[4:])
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}
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func (h rawHeader) String() string {
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return fmt.Sprintf("Version:%d Cmd:%d StreamID:%d Length:%d",
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h.Version(), h.Cmd(), h.StreamID(), h.Length())
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}
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