// the process's memory.
func (c *Cipher) Reset() {
	for i := range c.s {
		c.s[i] = 0
	}
	c.i, c.j = 0, 0
}

// XORKeyStream sets dst to the result of XORing src with the key stream.
// Dst and src must overlap entirely or not at all.
func (c *Cipher) XORKeyStream(dst, src []byte) {
	if len(src) == 0 {
		return
	}
	if alias.InexactOverlap(dst[:len(src)], src) {
		panic("crypto/rc4: invalid buffer overlap")

			encrypted := make([]byte, len(in))
			ctr.XORKeyStream(encrypted, in)
			if out := tt.out[0:len(in)]; !bytes.Equal(out, encrypted) {
				t.Errorf("%s/%d: CTR\ninpt %x\nhave %x\nwant %x", test, len(in), in, encrypted, out)
			}
		}

		for j := 0; j <= 7; j += 7 {
			in := tt.out[0 : len(tt.out)-j]
			ctr := cipher.NewCTR(c, tt.iv)
			plain := make([]byte, len(in))
			ctr.XORKeyStream(plain, in)

			continue
		}

		for j := 0; j <= 5; j += 5 {
			plaintext := tt.in[0 : len(tt.in)-j]
			ofb := cipher.NewOFB(c, tt.iv)
			ciphertext := make([]byte, len(plaintext))
			ofb.XORKeyStream(ciphertext, plaintext)
			if !bytes.Equal(ciphertext, tt.out[:len(plaintext)]) {
				t.Errorf("%s/%d: encrypting\ninput % x\nhave % x\nwant % x", test, len(plaintext), plaintext, ciphertext, tt.out)
			}
		}

	x.out = x.out[:cap(x.out)]
	for remain < len(x.out)-bs {
		x.b.Encrypt(x.cipher, x.cipher)
		copy(x.out[remain:], x.cipher)
		remain += bs
	}
	x.out = x.out[:remain]
	x.outUsed = 0
}

func (x *ofb) XORKeyStream(dst, src []byte) {
	if len(dst) < len(src) {
		panic("crypto/cipher: output smaller than input")
	}
	if alias.InexactOverlap(dst[:len(src)], src) {
		panic("crypto/cipher: invalid buffer overlap")
	}

		copy(want, src)
		counter := make([]byte, size)
		for i := 1; i < len(want)/size; i++ {
			inc(counter)
			xor(want[i*size:(i+1)*size], counter)
		}
		dst := make([]byte, 1024)
		ctr.XORKeyStream(dst, src)
		if !bytes.Equal(dst, want) {
			t.Errorf("for size %d\nhave %x\nwant %x", size, dst, want)
		}
	}

package cipher

import (
	"crypto/internal/alias"
	"crypto/subtle"
)

type cfb struct {
	b       Block
	next    []byte
	out     []byte
	outUsed int

	decrypt bool
}

func (x *cfb) XORKeyStream(dst, src []byte) {
	if len(dst) < len(src) {
		panic("crypto/cipher: output smaller than input")
	}
	if alias.InexactOverlap(dst[:len(src)], src) {
		panic("crypto/cipher: invalid buffer overlap")
	}

			c0++
		}
	}
	c.ctr[0], c.ctr[1] = c0, c1
	// Encrypt the buffer using AES in ECB mode.
	cryptBlocks(c.block.function, &c.block.key[0], &c.buffer[0], &c.buffer[0], streamBufferSize)
}

func (c *aesctr) XORKeyStream(dst, src []byte) {
	if len(dst) < len(src) {
		panic("crypto/cipher: output smaller than input")
	}
	if alias.InexactOverlap(dst[:len(src)], src) {
		panic("crypto/cipher: invalid buffer overlap")
	}

		// Increment counter
		for i := len(x.ctr) - 1; i >= 0; i-- {
			x.ctr[i]++
			if x.ctr[i] != 0 {
				break
			}
		}
	}
	x.out = x.out[:remain]
	x.outUsed = 0
}

func (x *ctr) XORKeyStream(dst, src []byte) {
	if len(dst) < len(src) {
		panic("crypto/cipher: output smaller than input")
	}
	if alias.InexactOverlap(dst[:len(src)], src) {
		panic("crypto/cipher: invalid buffer overlap")
	}

	b.SetBytes(int64(len(buf)))

	var key [16]byte
	var iv [16]byte
	aes, _ := aes.NewCipher(key[:])
	stream := mode(aes, iv[:])

	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		stream.XORKeyStream(buf, buf)
	}
}

// If we test exactly 1K blocks, we would generate exact multiples of
// the cipher's block size, and the cipher stream fragments would

		t.Fatalf("cipher.NewCBCDecrypter did not use cbcDecAble interface")
	}
}

// testStream implements the cipher.Stream interface.
type testStream struct{}

func (*testStream) XORKeyStream(a, b []byte) {}
func (*testStream) InAESPackage() bool       { return true }

// Test the ctrAble interface is detected correctly by the cipher package.
func TestCTRAble(t *testing.T) {