Plumb monotonic time to netstack

Netstack needs to be portable, so this seems to be preferable to using raw
system calls.

PiperOrigin-RevId: 212917409
Change-Id: I7b2073e7db4b4bf75300717ca23aea4c15be944c

1 files changed, 3 insertions, 8 deletions

diff --git a/pkg/tcpip/tcpip.go b/pkg/tcpip/tcpip.go
index 51360b11f..b1bd5117f 100644
--- a/pkg/tcpip/tcpip.go
+++ b/pkg/tcpip/tcpip.go
@@ -123,16 +123,11 @@ func (e ErrSaveRejection) Error() string {
 // time, but never for netstack internal timekeeping.
 type Clock interface {
 	// NowNanoseconds returns the current real time as a number of
-	// nanoseconds since some epoch.
+	// nanoseconds since the Unix epoch.
 	NowNanoseconds() int64
-}
-
-// StdClock implements Clock with the time package.
-type StdClock struct{}
 
-// NowNanoseconds implements Clock.NowNanoseconds.
-func (*StdClock) NowNanoseconds() int64 {
-	return time.Now().UnixNano()
+	// NowMonotonic returns a monotonic time value.
+	NowMonotonic() int64
 }
 
 // Address is a byte slice cast as a string that represents the address of a