package crypto/subtle
ConstantTimeLessOrEq returns 1 if x <= y and 0 otherwise. Its behavior is undefined if x(1st param) or y(2nd param) are negative or > 2**31 - 1.
Golang crypto/subtle.ConstantTimeLessOrEq() function usage example
package main
import (
"fmt"
"crypto/subtle"
)
func main() {
x := 3
y := 4
z := 1
n := subtle.ConstantTimeLessOrEq(x,y)
fmt.Printf("n : %d \n", n) // returns 1
nn := subtle.ConstantTimeLessOrEq(x,z)
fmt.Printf("nn : %d \n", nn) // returns 0
}
Output :
n : 1
nn : 0
Reference :
http://golang.org/pkg/crypto/subtle/#ConstantTimeLessOrEq
