diff options
Diffstat (limited to 'src/pkg/crypto/subtle/constant_time.go')
| -rw-r--r-- | src/pkg/crypto/subtle/constant_time.go | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/src/pkg/crypto/subtle/constant_time.go b/src/pkg/crypto/subtle/constant_time.go index 57dbe9db5..dfb658465 100644 --- a/src/pkg/crypto/subtle/constant_time.go +++ b/src/pkg/crypto/subtle/constant_time.go @@ -55,3 +55,11 @@ func ConstantTimeCopy(v int, x, y []byte) { } return } + +// ConstantTimeLessOrEq returns 1 if x <= y and 0 otherwise. +// Its behavior is undefined if x or y are negative or > 2**31 - 1. +func ConstantTimeLessOrEq(x, y int) int { + x32 := int32(x) + y32 := int32(y) + return int(((x32 - y32 - 1) >> 31) & 1) +} |