wireguard-go/tai64n/tai64n.go
Jason A. Donenfeld a5ca02d79a tai64n: whiten nano seconds
Avoid being too precise of a time oracle.
2019-02-05 12:59:42 +01:00

33 lines
659 B
Go

/* SPDX-License-Identifier: MIT
*
* Copyright (C) 2017-2019 WireGuard LLC. All Rights Reserved.
*/
package tai64n
import (
"bytes"
"encoding/binary"
"time"
)
const TimestampSize = 12
const base = uint64(0x400000000000000a)
const whitenerMask = uint32(0x1000000 - 1)
type Timestamp [TimestampSize]byte
func Now() Timestamp {
var tai64n Timestamp
now := time.Now()
secs := base + uint64(now.Unix())
nano := uint32(now.Nanosecond()) &^ whitenerMask
binary.BigEndian.PutUint64(tai64n[:], secs)
binary.BigEndian.PutUint32(tai64n[8:], nano)
return tai64n
}
func (t1 Timestamp) After(t2 Timestamp) bool {
return bytes.Compare(t1[:], t2[:]) > 0
}