broken checkpt

wire/wire_linux.go

@@ -0,0 +1,32 @@
+package wire
+
+import (
+	"fmt"
+
+	"github.com/slackhq/nebula/overlay/tio/virtio"
+)
+
+// PerSegment invokes fn once per segment of pkt. For non-GSO pkts
+// fn is called once with pkt.Bytes (no segmentation, no copy). For GSO/USO
+// superpackets fn is called once per segment with a slice of pkt.Bytes
+// holding that segment's plaintext (a freshly-patched L3+L4 header sliced
+// in front of the original payload chunk). The slide is destructive: pkt is
+// consumed by this call and its bytes are in an undefined state when
+// PerSegment returns. Callers must not retain pkt or any earlier
+// seg slice past fn's return for that segment. The scratch parameter is
+// unused on the destructive path and kept only for cross-platform
+// signature compatibility. Aborts and returns the first error from fn or
+// from per-segment construction.
+func (t *TunPacket) PerSegment(fn func(seg []byte) error) error {
+	if !t.Meta.IsSuperpacket() {
+		return fn(t.Bytes)
+	}
+	switch t.Meta.Proto {
+	case GSOProtoTCP:
+		return virtio.SegmentTCP(t.Bytes, t.Meta.HdrLen, t.Meta.CsumStart, t.Meta.Size, fn)
+	case GSOProtoUDP:
+		return virtio.SegmentUDP(t.Bytes, t.Meta.HdrLen, t.Meta.CsumStart, t.Meta.Size, fn)
+	default:
+		return fmt.Errorf("unsupported gso proto: %d", t.Meta.Proto)
+	}
+}