tai64n: whiten nano seconds

Avoid being too precise of a time oracle.

diff --git a/tai64n/tai64n.go b/tai64n/tai64n.go
index f402f058cb7c94db606f93527fd504f1d80a9522..565aaa4b6831f0ea926c397535e656f60474119d 100644 (file)
--- a/tai64n/tai64n.go
+++ b/tai64n/tai64n.go
@@ -12,7 +12,8 @@ import (
 )
 
 const TimestampSize = 12
-const base = uint64(4611686018427387914)
+const base = uint64(0x400000000000000a)
+const whitenerMask = uint32(0x1000000 - 1)
 
 type Timestamp [TimestampSize]byte
 
@@ -20,7 +21,7 @@ func Now() Timestamp {
        var tai64n Timestamp
        now := time.Now()
        secs := base + uint64(now.Unix())
-       nano := uint32(now.Nanosecond())
+       nano := uint32(now.Nanosecond()) &^ whitenerMask
        binary.BigEndian.PutUint64(tai64n[:], secs)
        binary.BigEndian.PutUint32(tai64n[8:], nano)
        return tai64n