96 lines
1.7 KiB
Go
96 lines
1.7 KiB
Go
package telebit
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import (
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"errors"
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"fmt"
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"os"
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"git.rootprojects.org/root/telebit/dbg"
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)
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type Parser struct {
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handler Router
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newConns chan *Conn
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conns map[string]*Conn
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state ParserState
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parseState State
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dataReady chan struct{}
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data []byte
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consumed int
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}
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type ParserState struct {
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consumed int
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version byte
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headerLen int
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header []byte
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payloadLen int
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srcAddr Addr
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dstAddr Addr
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payloadWritten int
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}
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type State int
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const (
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V1 byte = 255 - (1 + iota)
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V2
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)
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const (
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VersionState State = 0
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)
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func NewParser(handler Router) *Parser {
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return &Parser{
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conns: make(map[string]*Conn),
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newConns: make(chan *Conn, 2), // Buffered to make testing easier
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dataReady: make(chan struct{}, 2),
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data: []byte{},
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handler: handler,
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}
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}
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type Router interface {
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RouteBytes(src, dst Addr, payload []byte)
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}
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// Write receives tunnel data and creates or writes to connections
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func (p *Parser) Write(b []byte) (int, error) {
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if len(b) < 1 {
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return 0, errors.New("developer error: wrote 0 bytes")
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}
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/*
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// so that we can overwrite the main state
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// as soon as a full message has completed
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// but still keep the number of bytes written
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if 0 == p.state.written {
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p.written = 0
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}
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*/
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switch p.parseState {
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case VersionState:
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if dbg.Debug {
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fmt.Fprintf(os.Stderr, "[debug] MPLEXY version byte %v %s", b[0], string(b))
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}
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p.state.version = b[0]
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b = b[1:]
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p.consumed++
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p.parseState++
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default:
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// do nothing
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}
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switch p.state.version {
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case V1:
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if dbg.Debug {
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fmt.Fprintf(os.Stderr, "[debug] MPLEXY packet is of type v1\n")
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}
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return p.unpackV1(b)
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default:
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return 0, errors.New("incorrect version or version not implemented")
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}
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}
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