add (c)SHAKE-128 and 256

shake
magical 2024-10-05 23:30:02 -07:00
parent 883cbd827a
commit 6bebd054b1
2 changed files with 271 additions and 0 deletions

147
shake.go 100644
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@ -0,0 +1,147 @@
package keccak
import "math/bits"
type Shake struct {
digest
initialState *[25]uint64 // todo: unique.Handle?
running uint8
}
func NewShake128(N, S []byte) *Shake { return newShake(N, S, 128/8) }
func NewShake256(N, S []byte) *Shake { return newShake(N, S, 256/8) }
func newShake(N, S []byte, sizeBytes int) *Shake {
s := new(Shake)
s.digest.size = sizeBytes
if len(N) == 0 && len(S) == 0 {
s.digest.dsbyte = 0x1f // 1111 10...
} else {
// cSHAKE
s.digest.dsbyte = 0x04 // 00 10...
rate := s.digest.BlockSize()
s.digest.Write(leftEncode(uint64(rate))) // rate in bytes
s.digest.Write(leftEncode(uint64(len(N)) * 8)) // length of N in bits
s.digest.Write(N)
s.digest.Write(leftEncode(uint64(len(S)) * 8)) // length of S in bits
s.digest.Write(S)
if s.len > 0 {
s.pad(rate)
s.flush()
}
}
//s.Reset()
return s
}
func (s *Shake) pad8() {
n := -s.len & 7
for i := 0; i < n; i++ {
s.buf[s.len+i] = 0
}
s.len += n
}
func (s *Shake) pad(rate int) {
for i := s.len; i < rate && i < len(s.buf); i++ {
s.buf[i] = 0
}
s.len = rate
}
// Shake is only resettable if Reset is called before the first Write or Read.
// (The first call to Reset makes a copy of the initial state which is restored
// on subsequent calls.)
func (s *Shake) Reset() {
if s.running == 0 {
if s.initialState == nil {
s.initialState = new([25]uint64)
*s.initialState = s.a
}
} else {
if s.initialState == nil {
panic("keccak: Reset called after Read or Write")
}
s.a = *s.initialState
s.buf = [200]byte{}
s.len = 0
s.running = 0
}
}
func (s *Shake) Write(p []byte) (int, error) {
s.running = 1
return s.digest.Write(p)
}
func (s *Shake) Read(p []byte) (int, error) {
if s.running < 2 && len(p) > 0 {
s.running = 2
s.buf[s.len] = s.dsbyte
bs := s.BlockSize()
for i := s.len + 1; i < bs; i++ {
s.buf[i] = 0
}
s.buf[bs-1] |= 0x80
for i := range s.a {
if i*8 > bs {
break
}
s.a[i] ^= le64dec(s.buf[i*8:])
}
s.len = bs
}
return s.digest.read(p)
}
func (d *digest) read(p []byte) (int, error) {
bs := d.BlockSize()
size := len(p)
for len(p) > 0 {
if d.len == bs {
d.squeeze(bs)
}
n := copy(p, d.buf[:bs])
d.len += n
p = p[n:]
}
return size, nil
}
func (d *digest) squeeze(bs int) {
//fmt.Printf("Squeezing\n", d.len)
keccakf(&d.a)
b := d.buf[:bs]
for i := range d.a {
if len(b) == 0 {
break
}
le64enc(b[:0], d.a[i]) // append
b = b[8:]
}
d.len = 0
}
func leftEncode(x uint64) []byte {
var out [9]byte
be64enc(out[1:], x)
i := bits.LeadingZeros64(x|1) / 8 // 0..7
out[i] = byte(8 - i)
return out[i:]
}
func be64enc(b []byte, x uint64) {
_ = b[7]
b[0] = byte(x >> 56)
b[1] = byte(x >> 48)
b[2] = byte(x >> 40)
b[3] = byte(x >> 32)
b[4] = byte(x >> 24)
b[5] = byte(x >> 16)
b[6] = byte(x >> 8)
b[7] = byte(x)
}

124
shake_test.go 100644
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@ -0,0 +1,124 @@
package keccak
import (
"bytes"
"fmt"
"testing"
)
func TestShake(t *testing.T) {
tests := []struct {
function string
F, S []byte
input string
digest string
}{
{
function: "shake128",
digest: "027cfb9e61ea1419dfce3b48e6bcb0b6b692fa2904751e5391c9ed468e010d5946f6f7c2be344c3ac2d722d96cf2a9a115681e22fcb43fd162a830b2079b527b",
},
{
function: "shake256",
digest: "f08a3125f880d9a58e0603ed5ae3778d33b8ccc795e0c18c9b9d735caa079440c6ab577eca4e0d898d966c4b730aee69307af26e459a0332367129476c381817",
},
{
function: "shake256",
input: "odd output",
digest: "678cc171bbc31a40c50d5e",
},
{
function: "cshake256",
F: []byte("FunctionName"),
S: []byte("CustomizationString"),
digest: "e80473cc7466ed4de29611752502ab9c5597818d",
},
}
for _, tt := range tests {
want := tt.digest
var sh *Shake
switch tt.function {
case "shake128":
sh = NewShake128(nil, nil)
case "shake256":
sh = NewShake256(nil, nil)
case "cshake256":
sh = NewShake256(tt.F, tt.S)
}
if tt.input == "" {
sh.Write([]byte("hello keccak"))
} else {
sh.Write([]byte(tt.input))
}
out := make([]byte, len(want)/2)
sh.Read(out)
got := fmt.Sprintf("%x", out)
if want != got {
t.Errorf("%s: got %s want %s", tt.function, got, want)
}
}
}
func TestShakeNIST(t *testing.T) {
sh := NewShake256(nil, nil)
want := shake256_digest_m0[:]
out := make([]byte, len(want))
n, err := sh.Read(out)
if n != len(out) || err != nil {
t.Errorf("unexpected return value: want (0, nil) got (%v,%v)", n, err)
}
if !bytes.Equal(want, out) {
t.Errorf("hash output:\nwant %x\ngot %x", want, out)
for i := range want {
if want[i] != out[i] {
t.Logf("note: first difference is at index %d", i)
break
}
}
}
}
// NIST test vector
var shake256_digest_m0 = [...]byte{
0x46, 0xB9, 0xDD, 0x2B, 0x0B, 0xA8, 0x8D, 0x13, 0x23, 0x3B, 0x3F, 0xEB, 0x74,
0x3E, 0xEB, 0x24, 0x3F, 0xCD, 0x52, 0xEA, 0x62, 0xB8, 0x1B, 0x82, 0xB5, 0x0C,
0x27, 0x64, 0x6E, 0xD5, 0x76, 0x2F, 0xD7, 0x5D, 0xC4, 0xDD, 0xD8, 0xC0, 0xF2,
0x00, 0xCB, 0x05, 0x01, 0x9D, 0x67, 0xB5, 0x92, 0xF6, 0xFC, 0x82, 0x1C, 0x49,
0x47, 0x9A, 0xB4, 0x86, 0x40, 0x29, 0x2E, 0xAC, 0xB3, 0xB7, 0xC4, 0xBE, 0x14,
0x1E, 0x96, 0x61, 0x6F, 0xB1, 0x39, 0x57, 0x69, 0x2C, 0xC7, 0xED, 0xD0, 0xB4,
0x5A, 0xE3, 0xDC, 0x07, 0x22, 0x3C, 0x8E, 0x92, 0x93, 0x7B, 0xEF, 0x84, 0xBC,
0x0E, 0xAB, 0x86, 0x28, 0x53, 0x34, 0x9E, 0xC7, 0x55, 0x46, 0xF5, 0x8F, 0xB7,
0xC2, 0x77, 0x5C, 0x38, 0x46, 0x2C, 0x50, 0x10, 0xD8, 0x46, 0xC1, 0x85, 0xC1,
0x51, 0x11, 0xE5, 0x95, 0x52, 0x2A, 0x6B, 0xCD, 0x16, 0xCF, 0x86, 0xF3, 0xD1,
0x22, 0x10, 0x9E, 0x3B, 0x1F, 0xDD, 0x94, 0x3B, 0x6A, 0xEC, 0x46, 0x8A, 0x2D,
0x62, 0x1A, 0x7C, 0x06, 0xC6, 0xA9, 0x57, 0xC6, 0x2B, 0x54, 0xDA, 0xFC, 0x3B,
0xE8, 0x75, 0x67, 0xD6, 0x77, 0x23, 0x13, 0x95, 0xF6, 0x14, 0x72, 0x93, 0xB6,
0x8C, 0xEA, 0xB7, 0xA9, 0xE0, 0xC5, 0x8D, 0x86, 0x4E, 0x8E, 0xFD, 0xE4, 0xE1,
0xB9, 0xA4, 0x6C, 0xBE, 0x85, 0x47, 0x13, 0x67, 0x2F, 0x5C, 0xAA, 0xAE, 0x31,
0x4E, 0xD9, 0x08, 0x3D, 0xAB, 0x4B, 0x09, 0x9F, 0x8E, 0x30, 0x0F, 0x01, 0xB8,
0x65, 0x0F, 0x1F, 0x4B, 0x1D, 0x8F, 0xCF, 0x3F, 0x3C, 0xB5, 0x3F, 0xB8, 0xE9,
0xEB, 0x2E, 0xA2, 0x03, 0xBD, 0xC9, 0x70, 0xF5, 0x0A, 0xE5, 0x54, 0x28, 0xA9,
0x1F, 0x7F, 0x53, 0xAC, 0x26, 0x6B, 0x28, 0x41, 0x9C, 0x37, 0x78, 0xA1, 0x5F,
0xD2, 0x48, 0xD3, 0x39, 0xED, 0xE7, 0x85, 0xFB, 0x7F, 0x5A, 0x1A, 0xAA, 0x96,
0xD3, 0x13, 0xEA, 0xCC, 0x89, 0x09, 0x36, 0xC1, 0x73, 0xCD, 0xCD, 0x0F, 0xAB,
0x88, 0x2C, 0x45, 0x75, 0x5F, 0xEB, 0x3A, 0xED, 0x96, 0xD4, 0x77, 0xFF, 0x96,
0x39, 0x0B, 0xF9, 0xA6, 0x6D, 0x13, 0x68, 0xB2, 0x08, 0xE2, 0x1F, 0x7C, 0x10,
0xD0, 0x4A, 0x3D, 0xBD, 0x4E, 0x36, 0x06, 0x33, 0xE5, 0xDB, 0x4B, 0x60, 0x26,
0x01, 0xC1, 0x4C, 0xEA, 0x73, 0x7D, 0xB3, 0xDC, 0xF7, 0x22, 0x63, 0x2C, 0xC7,
0x78, 0x51, 0xCB, 0xDD, 0xE2, 0xAA, 0xF0, 0xA3, 0x3A, 0x07, 0xB3, 0x73, 0x44,
0x5D, 0xF4, 0x90, 0xCC, 0x8F, 0xC1, 0xE4, 0x16, 0x0F, 0xF1, 0x18, 0x37, 0x8F,
0x11, 0xF0, 0x47, 0x7D, 0xE0, 0x55, 0xA8, 0x1A, 0x9E, 0xDA, 0x57, 0xA4, 0xA2,
0xCF, 0xB0, 0xC8, 0x39, 0x29, 0xD3, 0x10, 0x91, 0x2F, 0x72, 0x9E, 0xC6, 0xCF,
0xA3, 0x6C, 0x6A, 0xC6, 0xA7, 0x58, 0x37, 0x14, 0x30, 0x45, 0xD7, 0x91, 0xCC,
0x85, 0xEF, 0xF5, 0xB2, 0x19, 0x32, 0xF2, 0x38, 0x61, 0xBC, 0xF2, 0x3A, 0x52,
0xB5, 0xDA, 0x67, 0xEA, 0xF7, 0xBA, 0xAE, 0x0F, 0x5F, 0xB1, 0x36, 0x9D, 0xB7,
0x8F, 0x3A, 0xC4, 0x5F, 0x8C, 0x4A, 0xC5, 0x67, 0x1D, 0x85, 0x73, 0x5C, 0xDD,
0xDB, 0x09, 0xD2, 0xB1, 0xE3, 0x4A, 0x1F, 0xC0, 0x66, 0xFF, 0x4A, 0x16, 0x2C,
0xB2, 0x63, 0xD6, 0x54, 0x12, 0x74, 0xAE, 0x2F, 0xCC, 0x86, 0x5F, 0x61, 0x8A,
0xBE, 0x27, 0xC1, 0x24, 0xCD, 0x8B, 0x07, 0x4C, 0xCD, 0x51, 0x63, 0x01, 0xB9,
0x18, 0x75, 0x82, 0x4D, 0x09, 0x95, 0x8F, 0x34, 0x1E, 0xF2, 0x74, 0xBD, 0xAB,
0x0B, 0xAE, 0x31, 0x63, 0x39, 0x89, 0x43, 0x04, 0xE3, 0x58, 0x77, 0xB0, 0xC2,
0x8A, 0x9B, 0x1F, 0xD1, 0x66, 0xC7, 0x96, 0xB9, 0xCC, 0x25, 0x8A, 0x06, 0x4A,
0x8F, 0x57, 0xE2, 0x7F, 0x2A,
}