decrypt in place

overlay/batch/passthrough.go

@@ -2,54 +2,27 @@ package batch
 
 import (
 	"io"
-
-	"github.com/slackhq/nebula/udp"
 )
 
 // Passthrough is a RxBatcher that doesn't batch anything, it just accumulates and then sends packets.
 type Passthrough struct {
-	out      io.Writer
-	slots    [][]byte
-	reserver Reserver
-	resetter Resetter
-	cursor   int
+	out   io.Writer
+	slots [][]byte
 }
 
-const passthroughBaseNumSlots = 128
-
-// DefaultPassthroughArenaCap is the recommended arena capacity for a
-// standalone Passthrough batcher: 128 slots × udp.MTU ≈ 1.1 MiB.
-const DefaultPassthroughArenaCap = passthroughBaseNumSlots * udp.MTU
-
-func NewPassthrough(w io.Writer, reserver Reserver, resetter Resetter) *Passthrough {
+func NewPassthrough(w io.Writer) *Passthrough {
 	return &Passthrough{
-		out:      w,
-		slots:    make([][]byte, 0, passthroughBaseNumSlots),
-		reserver: reserver,
-		resetter: resetter,
+		out:   w,
+		slots: make([][]byte, 0, 128),
 	}
 }
 
-func (p *Passthrough) Reserve(sz int) []byte {
-	return p.reserver(sz)
-}
-
 func (p *Passthrough) Commit(pkt []byte) error {
 	p.slots = append(p.slots, pkt)
 	return nil
 }
 
-// Flush drains every queued packet and calls the configured Resetter
 func (p *Passthrough) Flush() error {
-	firstErr := p.drain()
-	if p.resetter != nil {
-		p.resetter()
-	}
-	return firstErr
-}
-
-// drain writes out every queued packet and clears the slot list.
-func (p *Passthrough) drain() error {
 	var firstErr error
 	for _, s := range p.slots {
 		_, err := p.out.Write(s)