lsh512_generic.go

package lsh512

import (
	"encoding/binary"
	"hash"
	"math/bits"

	"github.com/RyuaNerin/go-krypto/internal/kryptoutil"
)

const (
	numStep = 28

	alphaEven = 23
	alphaOdd  = 7

	betaEven = 59
	betaOdd  = 3
)

var (
	iv224 = [...]uint64{
		0x0c401e9fe8813a55, 0x4a5f446268fd3d35, 0xff13e452334f612a, 0xf8227661037e354a,
		0xa5f223723c9ca29d, 0x95d965a11aed3979, 0x01e23835b9ab02cc, 0x52d49cbad5b30616,
		0x9e5c2027773f4ed3, 0x66a5c8801925b701, 0x22bbc85b4c6779d9, 0xc13171a42c559c23,
		0x31e2b67d25be3813, 0xd522c4deed8e4d83, 0xa79f5509b43fbafe, 0xe00d2cd88b4b6c6a,
	}

	iv256 = [...]uint64{
		0x6dc57c33df989423, 0xd8ea7f6e8342c199, 0x76df8356f8603ac4, 0x40f1b44de838223a,
		0x39ffe7cfc31484cd, 0x39c4326cc5281548, 0x8a2ff85a346045d8, 0xff202aa46dbdd61e,
		0xcf785b3cd5fcdb8b, 0x1f0323b64a8150bf, 0xff75d972f29ea355, 0x2e567f30bf1ca9e1,
		0xb596875bf8ff6dba, 0xfcca39b089ef4615, 0xecff4017d020b4b6, 0x7e77384c772ed802,
	}

	iv384 = [...]uint64{
		0x53156a66292808f6, 0xb2c4f362b204c2bc, 0xb84b7213bfa05c4e, 0x976ceb7c1b299f73,
		0xdf0cc63c0570ae97, 0xda4441baa486ce3f, 0x6559f5d9b5f2acc2, 0x22dacf19b4b52a16,
		0xbbcdacefde80953a, 0xc9891a2879725b3e, 0x7c9fe6330237e440, 0xa30ba550553f7431,
		0xbb08043fb34e3e30, 0xa0dec48d54618ead, 0x150317267464bc57, 0x32d1501fde63dc93,
	}

	iv512 = [...]uint64{
		0xadd50f3c7f07094e, 0xe3f3cee8f9418a4f, 0xb527ecde5b3d0ae9, 0x2ef6dec68076f501,
		0x8cb994cae5aca216, 0xfbb9eae4bba48cc7, 0x650a526174725fea, 0x1f9a61a73f8d8085,
		0xb6607378173b539b, 0x1bc99853b0c0b9ed, 0xdf727fc19b182d47, 0xdbef360cf893a457,
		0x4981f5e570147e80, 0xd00c4490ca7d3e30, 0x5d73940c0e4ae1ec, 0x894085e2edb2d819,
	}

	/// step 상수
	step = [...]uint64{
		0x97884283c938982a, 0xba1fca93533e2355, 0xc519a2e87aeb1c03, 0x9a0fc95462af17b1,
		0xfc3dda8ab019a82b, 0x02825d079a895407, 0x79f2d0a7ee06a6f7, 0xd76d15eed9fdf5fe,
		0x1fcac64d01d0c2c1, 0xd9ea5de69161790f, 0xdebc8b6366071fc8, 0xa9d91db711c6c94b,
		0x3a18653ac9c1d427, 0x84df64a223dd5b09, 0x6cc37895f4ad9e70, 0x448304c8d7f3f4d5,
		0xea91134ed29383e0, 0xc4484477f2da88e8, 0x9b47eec96d26e8a6, 0x82f6d4c8d89014f4,
		0x527da0048b95fb61, 0x644406c60138648d, 0x303c0e8aa24c0edc, 0xc787cda0cbe8ca19,
		0x7ba46221661764ca, 0x0c8cbc6acd6371ac, 0xe336b836940f8f41, 0x79cb9da168a50976,
		0xd01da49021915cb3, 0xa84accc7399cf1f1, 0x6c4a992cee5aeb0c, 0x4f556e6cb4b2e3e0,
		0x200683877d7c2f45, 0x9949273830d51db8, 0x19eeeecaa39ed124, 0x45693f0a0dae7fef,
		0xedc234b1b2ee1083, 0xf3179400d68ee399, 0xb6e3c61b4945f778, 0xa4c3db216796c42f,
		0x268a0b04f9ab7465, 0xe2705f6905f2d651, 0x08ddb96e426ff53d, 0xaea84917bc2e6f34,
		0xaff6e664a0fe9470, 0x0aab94d765727d8c, 0x9aa9e1648f3d702e, 0x689efc88fe5af3d3,
		0xb0950ffea51fd98b, 0x52cfc86ef8c92833, 0xe69727b0b2653245, 0x56f160d3ea9da3e2,
		0xa6dd4b059f93051f, 0xb6406c3cd7f00996, 0x448b45f3ccad9ec8, 0x079b8587594ec73b,
		0x45a50ea3c4f9653b, 0x22983767c1f15b85, 0x7dbed8631797782b, 0x485234be88418638,
		0x842850a5329824c5, 0xf6aca914c7f9a04c, 0xcfd139c07a4c670c, 0xa3210ce0a8160242,
		0xeab3b268be5ea080, 0xbacf9f29b34ce0a7, 0x3c973b7aaf0fa3a8, 0x9a86f346c9c7be80,
		0xac78f5d7cabcea49, 0xa355bddcc199ed42, 0xa10afa3ac6b373db, 0xc42ded88be1844e5,
		0x9e661b271cff216a, 0x8a6ec8dd002d8861, 0xd3d2b629beb34be4, 0x217a3a1091863f1a,
		0x256ecda287a733f5, 0xf9139a9e5b872fe5, 0xac0535017a274f7c, 0xf21b7646d65d2aa9,
		0x048142441c208c08, 0xf937a5dd2db5e9eb, 0xa688dfe871ff30b7, 0x9bb44aa217c5593b,
		0x943c702a2edb291a, 0x0cae38f9e2b715de, 0xb13a367ba176cc28, 0x0d91bd1d3387d49b,
		0x85c386603cac940c, 0x30dd830ae39fd5e4, 0x2f68c85a712fe85d, 0x4ffeecb9dd1e94d6,
		0xd0ac9a590a0443ae, 0xbae732dc99ccf3ea, 0xeb70b21d1842f4d9, 0x9f4eda50bb5c6fa8,
		0x4949e69ce940a091, 0x0e608dee8375ba14, 0x983122cba118458c, 0x4eeba696fbb36b25,
		0x7d46f3630e47f27e, 0xa21a0f7666c0dea4, 0x5c22cf355b37cec4, 0xee292b0c17cc1847,
		0x9330838629e131da, 0x6eee7c71f92fce22, 0xc953ee6cb95dd224, 0x3a923d92af1e9073,
		0xc43a5671563a70fb, 0xbc2985dd279f8346, 0x7ef2049093069320, 0x17543723e3e46035,
		0xc3b409b00b130c6d, 0x5d6aee6b28fdf090, 0x1d425b26172ff6ed, 0xcccfd041cdaf03ad,
		0xfe90c7c790ab6cbf, 0xe5af6304c722ca02, 0x70f695239999b39e, 0x6b8b5b07c844954c,
		0x77bdb9bb1e1f7a30, 0xc859599426ee80ed, 0x5f9d813d4726e40a, 0x9ca0120f7cb2b179,
		0x8f588f583c182cbd, 0x951267cbe9eccce7, 0x678bb8bd334d520e, 0xf6e662d00cd9e1b7,
		0x357774d93d99aaa7, 0x21b2edbb156f6eb5, 0xfd1ebe846e0aee69, 0x3cb2218c2f642b15,
		0xe7e7e7945444ea4c, 0xa77a33b5d6b9b47c, 0xf34475f0809f6075, 0xdd4932dce6bb99ad,
		0xacec4e16d74451dc, 0xd4a0a8d084de23d6, 0x1bdd42f278f95866, 0xeed3adbb938f4051,
		0xcfcf7be8992f3733, 0x21ade98c906e3123, 0x37ba66711fffd668, 0x267c0fc3a255478a,
		0x993a64ee1b962e88, 0x754979556301faaa, 0xf920356b7251be81, 0xc281694f22cf923f,
		0x9f4b6481c8666b02, 0xcf97761cfe9f5444, 0xf220d7911fd63e9f, 0xa28bd365f79cd1b0,
		0xd39f5309b1c4b721, 0xbec2ceb864fca51f, 0x1955a0ddc410407a, 0x43eab871f261d201,
		0xeaafe64a2ed16da1, 0x670d931b9df39913, 0x12f868b0f614de91, 0x2e5f395d946e8252,
		0x72f25cbb767bd8f4, 0x8191871d61a1c4dd, 0x6ef67ea1d450ba93, 0x2ea32a645433d344,
		0x9a963079003f0f8b, 0x74a0aeb9918cac7a, 0x0b6119a70af36fa3, 0x8d9896f202f0d480,
		0x654f1831f254cd66, 0x1318a47f0366a25e, 0x65752076250b4e01, 0xd1cd8eb888071772,
		0x30c6a9793f4e9b25, 0x154f684b1e3926ee, 0x6c7ac0b1fe6312ae, 0x262f88f4f3c5550d,
		0xb4674a24472233cb, 0x2bbd23826a090071, 0xda95969b30594f66, 0x9f5c47408f1e8a43,
		0xf77022b88de9c055, 0x64b7b36957601503, 0xe73b72b06175c11a, 0x55b87de8b91a6233,
		0x1bb16e6b6955ff7f, 0xe8e0a5ec7309719c, 0x702c31cb89a8b640, 0xfba387cfada8cde2,
		0x6792db4677aa164c, 0x1c6b1cc0b7751867, 0x22ae2311d736dc01, 0x0e3666a1d37c9588,
		0xcd1fd9d4bf557e9a, 0xc986925f7c7b0e84, 0x9c5dfd55325ef6b0, 0x9f2b577d5676b0dd,
		0xfa6e21be21c062b3, 0x8787dd782c8d7f83, 0xd0d134e90e12dd23, 0x449d087550121d96,
		0xecf9ae9414d41967, 0x5018f1dbf789934d, 0xfa5b52879155a74c, 0xca82d4d3cd278e7c,
		0x688fdfdfe22316ad, 0x0f6555a4ba0d030a, 0xa2061df720f000f3, 0xe1a57dc5622fb3da,
		0xe6a842a8e8ed8153, 0x690acdd3811ce09d, 0x55adda18e6fcf446, 0x4d57a8a0f4b60b46,
		0xf86fbfc20539c415, 0x74bafa5ec7100d19, 0xa824151810f0f495, 0x8723432791e38ebb,
		0x8eeaeb91d66ed539, 0x73d8a1549dfd7e06, 0x0387f2ffe3f13a9b, 0xa5004995aac15193,
		0x682f81c73efdda0d, 0x2fb55925d71d268d, 0xcc392d2901e58a3d, 0xaa666ab975724a42,
	}

	gamma = [...]int{0, 16, 32, 48, 8, 24, 40, 56}
)

type lsh512ContextGo struct {
	cv    [16]uint64
	tcv   [16]uint64
	msg   [16 * (numStep + 1)]uint64
	block [BlockSize]byte

	boff        int
	outlenbytes int
}

func newContextGo(size int) hash.Hash {
	ctx := new(lsh512ContextGo)
	initContextGo(ctx, size)
	return ctx
}

func initContextGo(ctx *lsh512ContextGo, size int) {
	ctx.outlenbytes = size
	ctx.Reset()
}

func sumGo(size int, data []byte) [Size]byte {
	var b lsh512ContextGo
	initContextGo(&b, size)
	b.Reset()
	b.Write(data)

	return b.checkSum()
}

func (b *lsh512ContextGo) Size() int {
	return b.outlenbytes
}

func (b *lsh512ContextGo) BlockSize() int {
	return BlockSize
}

func (b *lsh512ContextGo) Reset() {
	kryptoutil.MemsetUint64(b.tcv[:], 0)
	kryptoutil.MemsetUint64(b.msg[:], 0)
	kryptoutil.MemsetByte(b.block[:], 0)

	b.boff = 0
	switch b.outlenbytes {
	case Size:
		b.cv = iv512
	case Size384:
		b.cv = iv384
	case Size256:
		b.cv = iv256
	case Size224:
		b.cv = iv224
	}
}

func (b *lsh512ContextGo) Write(p []byte) (n int, err error) {
	if p == nil || len(p) == 0 {
		return
	}

	gap := BlockSize - b.boff
	if b.boff > 0 && len(p) >= gap {
		copy(b.block[b.boff:], p[:gap])
		b.compress(b.block[:])
		b.boff = 0

		p = p[gap:]
	}

	for len(p) >= BlockSize {
		b.compress(p)
		b.boff = 0
		p = p[BlockSize:]
	}

	if len(p) > 0 {
		copy(b.block[b.boff:], p)
		b.boff += len(p)
	}

	return len(p), nil
}

func (b *lsh512ContextGo) Sum(p []byte) []byte {
	b0 := *b
	hash := b0.checkSum()
	return append(p, hash[:b.Size()]...)
}

func (b *lsh512ContextGo) checkSum() [Size]byte {
	b.block[b.boff] = 0x80

	kryptoutil.MemsetByte(b.block[b.boff+1:], 0)
	b.compress(b.block[:])

	var temp [8]uint64
	for i := 0; i < 8; i++ {
		temp[i] = b.cv[i] ^ b.cv[i+8]
	}

	var digest [Size]byte
	for i := 0; i < b.outlenbytes; i++ {
		digest[i] = byte(temp[i>>3] >> ((i << 3) & 0x3f))
	}

	return digest
}

func (b *lsh512ContextGo) compress(data []byte) {
	b.msgExpansion(data)

	for i := 0; i < numStep/2; i++ {
		b.step(2*i, alphaEven, betaEven)
		b.step(2*i+1, alphaOdd, betaOdd)
	}

	// msg add
	for i := 0; i < 16; i++ {
		b.cv[i] ^= b.msg[16*numStep+i]
	}
}

func (b *lsh512ContextGo) msgExpansion(in []byte) {
	for i := 0; i < 32; i++ {
		b.msg[i] = binary.LittleEndian.Uint64(in[i*8:])
	}

	for i := 2; i <= numStep; i++ {
		idx := 16 * i
		b.msg[idx+0] = b.msg[idx-16] + b.msg[idx-29]
		b.msg[idx+1] = b.msg[idx-15] + b.msg[idx-30]
		b.msg[idx+2] = b.msg[idx-14] + b.msg[idx-32]
		b.msg[idx+3] = b.msg[idx-13] + b.msg[idx-31]
		b.msg[idx+4] = b.msg[idx-12] + b.msg[idx-25]
		b.msg[idx+5] = b.msg[idx-11] + b.msg[idx-28]
		b.msg[idx+6] = b.msg[idx-10] + b.msg[idx-27]
		b.msg[idx+7] = b.msg[idx-9] + b.msg[idx-26]
		b.msg[idx+8] = b.msg[idx-8] + b.msg[idx-21]
		b.msg[idx+9] = b.msg[idx-7] + b.msg[idx-22]
		b.msg[idx+10] = b.msg[idx-6] + b.msg[idx-24]
		b.msg[idx+11] = b.msg[idx-5] + b.msg[idx-23]
		b.msg[idx+12] = b.msg[idx-4] + b.msg[idx-17]
		b.msg[idx+13] = b.msg[idx-3] + b.msg[idx-20]
		b.msg[idx+14] = b.msg[idx-2] + b.msg[idx-19]
		b.msg[idx+15] = b.msg[idx-1] + b.msg[idx-18]
	}
}

func (b *lsh512ContextGo) step(stepidx, alpha, beta int) {
	var vl, vr uint64

	for colidx := 0; colidx < 8; colidx++ {
		vl = b.cv[colidx] ^ b.msg[16*stepidx+colidx]
		vr = b.cv[colidx+8] ^ b.msg[16*stepidx+colidx+8]
		vl = bits.RotateLeft64(vl+vr, alpha) ^ step[8*stepidx+colidx]
		vr = bits.RotateLeft64(vl+vr, beta)
		b.tcv[colidx] = vr + vl
		b.tcv[colidx+8] = bits.RotateLeft64(vr, gamma[colidx])
	}

	// wordPermutation
	b.cv[0] = b.tcv[6]
	b.cv[1] = b.tcv[4]
	b.cv[2] = b.tcv[5]
	b.cv[3] = b.tcv[7]
	b.cv[4] = b.tcv[12]
	b.cv[5] = b.tcv[15]
	b.cv[6] = b.tcv[14]
	b.cv[7] = b.tcv[13]
	b.cv[8] = b.tcv[2]
	b.cv[9] = b.tcv[0]
	b.cv[10] = b.tcv[1]
	b.cv[11] = b.tcv[3]
	b.cv[12] = b.tcv[8]
	b.cv[13] = b.tcv[11]
	b.cv[14] = b.tcv[10]
	b.cv[15] = b.tcv[9]
}