mirror of
https://github.com/gravitational/teleport
synced 2024-10-22 18:23:25 +00:00
46 lines
1.3 KiB
Go
46 lines
1.3 KiB
Go
/*
|
|
Copyright 2015 Gravitational, Inc.
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
|
you may not use this file except in compliance with the License.
|
|
You may obtain a copy of the License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License.
|
|
*/
|
|
|
|
package utils
|
|
|
|
import (
|
|
"crypto/rand"
|
|
"encoding/hex"
|
|
"math/big"
|
|
"time"
|
|
|
|
"github.com/gravitational/trace"
|
|
)
|
|
|
|
// CryptoRandomHex returns hex encoded random string generated with crypto-strong
|
|
// pseudo random generator of the given bytes
|
|
func CryptoRandomHex(len int) (string, error) {
|
|
randomBytes := make([]byte, len)
|
|
if _, err := rand.Reader.Read(randomBytes); err != nil {
|
|
return "", trace.Wrap(err)
|
|
}
|
|
return hex.EncodeToString(randomBytes), nil
|
|
}
|
|
|
|
// RandomDuration returns a duration in a range [0, max)
|
|
func RandomDuration(max time.Duration) time.Duration {
|
|
randomVal, err := rand.Int(rand.Reader, big.NewInt(int64(max)))
|
|
if err != nil {
|
|
return max / 2
|
|
}
|
|
return time.Duration(randomVal.Int64())
|
|
}
|