shield/stream/stream_test.go

package stream

import "testing"

type fakePRNG struct{}

func (*fakePRNG) Uint64() uint64 {
	return uint64(0XDEADBEEF)
}

func TestStreamCipher(t *testing.T) {
	plaintext := []byte("hello, world")

	ciphertext := make([]byte, len(plaintext))
	c1 := NewCipher(new(fakePRNG))
	c1.XORKeyStream(ciphertext, plaintext)

	plaintext2 := make([]byte, len(plaintext))
	c2 := NewCipher(new(fakePRNG))
	c2.XORKeyStream(plaintext2, ciphertext)

	for i, v := range plaintext2 {
		if v != plaintext[i] {
			t.Fatalf("mismatch at byte %d:\nhave: % x\nwant: % x", i, plaintext2, plaintext)
		}
	}
}

func BenchmarkXORKeyStream(b *testing.B) {
	plaintext := make([]byte, 1500)
	ciphertext := make([]byte, len(plaintext))
	c := NewCipher(new(fakePRNG))

	b.ResetTimer()
	for n := 0; n < b.N; n++ {
		c.XORKeyStream(ciphertext, plaintext)
	}
	b.SetBytes(int64(len(plaintext)))
}