blob: 661bde397e43924d519ca77b7fa3a400191ca71c [file] [log] [blame]
// Copyright 2021 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package fiat_test
import (
"crypto/elliptic/internal/fiat"
"crypto/rand"
"testing"
)
func p521Random(t *testing.T) *fiat.P521Element {
buf := make([]byte, 66)
if _, err := rand.Read(buf); err != nil {
t.Fatal(err)
}
buf[65] &= 1
e, err := new(fiat.P521Element).SetBytes(buf)
if err != nil {
t.Fatal(err)
}
return e
}
func TestP521Invert(t *testing.T) {
a := p521Random(t)
inv := new(fiat.P521Element).Invert(a)
one := new(fiat.P521Element).Mul(a, inv)
if new(fiat.P521Element).One().Equal(one) != 1 {
t.Errorf("a * 1/a != 1; got %x for %x", one.Bytes(), a.Bytes())
}
inv.Invert(new(fiat.P521Element))
if new(fiat.P521Element).Equal(inv) != 1 {
t.Errorf("1/0 != 0; got %x", inv.Bytes())
}
}