619 lines
17 KiB
Go
619 lines
17 KiB
Go
package kcp
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import (
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"crypto/aes"
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"crypto/cipher"
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"crypto/des"
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"crypto/sha1"
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"unsafe"
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xor "github.com/templexxx/xorsimd"
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"github.com/tjfoc/gmsm/sm4"
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"golang.org/x/crypto/blowfish"
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"golang.org/x/crypto/cast5"
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"golang.org/x/crypto/pbkdf2"
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"golang.org/x/crypto/salsa20"
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"golang.org/x/crypto/tea"
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"golang.org/x/crypto/twofish"
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"golang.org/x/crypto/xtea"
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)
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var (
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initialVector = []byte{167, 115, 79, 156, 18, 172, 27, 1, 164, 21, 242, 193, 252, 120, 230, 107}
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saltxor = `sH3CIVoF#rWLtJo6`
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)
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// BlockCrypt defines encryption/decryption methods for a given byte slice.
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// Notes on implementing: the data to be encrypted contains a builtin
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// nonce at the first 16 bytes
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type BlockCrypt interface {
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// Encrypt encrypts the whole block in src into dst.
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// Dst and src may point at the same memory.
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Encrypt(dst, src []byte)
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// Decrypt decrypts the whole block in src into dst.
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// Dst and src may point at the same memory.
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Decrypt(dst, src []byte)
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}
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type salsa20BlockCrypt struct {
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key [32]byte
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}
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// NewSalsa20BlockCrypt https://en.wikipedia.org/wiki/Salsa20
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func NewSalsa20BlockCrypt(key []byte) (BlockCrypt, error) {
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c := new(salsa20BlockCrypt)
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copy(c.key[:], key)
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return c, nil
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}
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func (c *salsa20BlockCrypt) Encrypt(dst, src []byte) {
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salsa20.XORKeyStream(dst[8:], src[8:], src[:8], &c.key)
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copy(dst[:8], src[:8])
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}
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func (c *salsa20BlockCrypt) Decrypt(dst, src []byte) {
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salsa20.XORKeyStream(dst[8:], src[8:], src[:8], &c.key)
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copy(dst[:8], src[:8])
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}
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type sm4BlockCrypt struct {
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encbuf [sm4.BlockSize]byte // 64bit alignment enc/dec buffer
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decbuf [2 * sm4.BlockSize]byte
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block cipher.Block
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}
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// NewSM4BlockCrypt https://github.com/tjfoc/gmsm/tree/master/sm4
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func NewSM4BlockCrypt(key []byte) (BlockCrypt, error) {
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c := new(sm4BlockCrypt)
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block, err := sm4.NewCipher(key)
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if err != nil {
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return nil, err
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}
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c.block = block
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return c, nil
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}
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func (c *sm4BlockCrypt) Encrypt(dst, src []byte) { encrypt(c.block, dst, src, c.encbuf[:]) }
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func (c *sm4BlockCrypt) Decrypt(dst, src []byte) { decrypt(c.block, dst, src, c.decbuf[:]) }
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type twofishBlockCrypt struct {
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encbuf [twofish.BlockSize]byte
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decbuf [2 * twofish.BlockSize]byte
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block cipher.Block
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}
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// NewTwofishBlockCrypt https://en.wikipedia.org/wiki/Twofish
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func NewTwofishBlockCrypt(key []byte) (BlockCrypt, error) {
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c := new(twofishBlockCrypt)
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block, err := twofish.NewCipher(key)
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if err != nil {
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return nil, err
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}
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c.block = block
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return c, nil
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}
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func (c *twofishBlockCrypt) Encrypt(dst, src []byte) { encrypt(c.block, dst, src, c.encbuf[:]) }
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func (c *twofishBlockCrypt) Decrypt(dst, src []byte) { decrypt(c.block, dst, src, c.decbuf[:]) }
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type tripleDESBlockCrypt struct {
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encbuf [des.BlockSize]byte
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decbuf [2 * des.BlockSize]byte
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block cipher.Block
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}
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// NewTripleDESBlockCrypt https://en.wikipedia.org/wiki/Triple_DES
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func NewTripleDESBlockCrypt(key []byte) (BlockCrypt, error) {
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c := new(tripleDESBlockCrypt)
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block, err := des.NewTripleDESCipher(key)
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if err != nil {
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return nil, err
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}
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c.block = block
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return c, nil
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}
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func (c *tripleDESBlockCrypt) Encrypt(dst, src []byte) { encrypt(c.block, dst, src, c.encbuf[:]) }
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func (c *tripleDESBlockCrypt) Decrypt(dst, src []byte) { decrypt(c.block, dst, src, c.decbuf[:]) }
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type cast5BlockCrypt struct {
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encbuf [cast5.BlockSize]byte
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decbuf [2 * cast5.BlockSize]byte
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block cipher.Block
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}
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// NewCast5BlockCrypt https://en.wikipedia.org/wiki/CAST-128
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func NewCast5BlockCrypt(key []byte) (BlockCrypt, error) {
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c := new(cast5BlockCrypt)
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block, err := cast5.NewCipher(key)
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if err != nil {
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return nil, err
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}
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c.block = block
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return c, nil
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}
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func (c *cast5BlockCrypt) Encrypt(dst, src []byte) { encrypt(c.block, dst, src, c.encbuf[:]) }
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func (c *cast5BlockCrypt) Decrypt(dst, src []byte) { decrypt(c.block, dst, src, c.decbuf[:]) }
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type blowfishBlockCrypt struct {
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encbuf [blowfish.BlockSize]byte
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decbuf [2 * blowfish.BlockSize]byte
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block cipher.Block
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}
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// NewBlowfishBlockCrypt https://en.wikipedia.org/wiki/Blowfish_(cipher)
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func NewBlowfishBlockCrypt(key []byte) (BlockCrypt, error) {
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c := new(blowfishBlockCrypt)
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block, err := blowfish.NewCipher(key)
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if err != nil {
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return nil, err
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}
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c.block = block
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return c, nil
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}
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func (c *blowfishBlockCrypt) Encrypt(dst, src []byte) { encrypt(c.block, dst, src, c.encbuf[:]) }
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func (c *blowfishBlockCrypt) Decrypt(dst, src []byte) { decrypt(c.block, dst, src, c.decbuf[:]) }
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type aesBlockCrypt struct {
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encbuf [aes.BlockSize]byte
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decbuf [2 * aes.BlockSize]byte
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block cipher.Block
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}
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// NewAESBlockCrypt https://en.wikipedia.org/wiki/Advanced_Encryption_Standard
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func NewAESBlockCrypt(key []byte) (BlockCrypt, error) {
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c := new(aesBlockCrypt)
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block, err := aes.NewCipher(key)
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if err != nil {
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return nil, err
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}
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c.block = block
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return c, nil
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}
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func (c *aesBlockCrypt) Encrypt(dst, src []byte) { encrypt(c.block, dst, src, c.encbuf[:]) }
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func (c *aesBlockCrypt) Decrypt(dst, src []byte) { decrypt(c.block, dst, src, c.decbuf[:]) }
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type teaBlockCrypt struct {
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encbuf [tea.BlockSize]byte
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decbuf [2 * tea.BlockSize]byte
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block cipher.Block
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}
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// NewTEABlockCrypt https://en.wikipedia.org/wiki/Tiny_Encryption_Algorithm
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func NewTEABlockCrypt(key []byte) (BlockCrypt, error) {
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c := new(teaBlockCrypt)
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block, err := tea.NewCipherWithRounds(key, 16)
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if err != nil {
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return nil, err
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}
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c.block = block
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return c, nil
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}
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func (c *teaBlockCrypt) Encrypt(dst, src []byte) { encrypt(c.block, dst, src, c.encbuf[:]) }
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func (c *teaBlockCrypt) Decrypt(dst, src []byte) { decrypt(c.block, dst, src, c.decbuf[:]) }
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type xteaBlockCrypt struct {
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encbuf [xtea.BlockSize]byte
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decbuf [2 * xtea.BlockSize]byte
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block cipher.Block
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}
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// NewXTEABlockCrypt https://en.wikipedia.org/wiki/XTEA
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func NewXTEABlockCrypt(key []byte) (BlockCrypt, error) {
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c := new(xteaBlockCrypt)
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block, err := xtea.NewCipher(key)
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if err != nil {
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return nil, err
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}
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c.block = block
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return c, nil
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}
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func (c *xteaBlockCrypt) Encrypt(dst, src []byte) { encrypt(c.block, dst, src, c.encbuf[:]) }
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func (c *xteaBlockCrypt) Decrypt(dst, src []byte) { decrypt(c.block, dst, src, c.decbuf[:]) }
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type simpleXORBlockCrypt struct {
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xortbl []byte
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}
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// NewSimpleXORBlockCrypt simple xor with key expanding
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func NewSimpleXORBlockCrypt(key []byte) (BlockCrypt, error) {
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c := new(simpleXORBlockCrypt)
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c.xortbl = pbkdf2.Key(key, []byte(saltxor), 32, mtuLimit, sha1.New)
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return c, nil
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}
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func (c *simpleXORBlockCrypt) Encrypt(dst, src []byte) { xor.Bytes(dst, src, c.xortbl) }
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func (c *simpleXORBlockCrypt) Decrypt(dst, src []byte) { xor.Bytes(dst, src, c.xortbl) }
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type noneBlockCrypt struct{}
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// NewNoneBlockCrypt does nothing but copying
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func NewNoneBlockCrypt(key []byte) (BlockCrypt, error) {
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return new(noneBlockCrypt), nil
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}
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func (c *noneBlockCrypt) Encrypt(dst, src []byte) { copy(dst, src) }
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func (c *noneBlockCrypt) Decrypt(dst, src []byte) { copy(dst, src) }
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// packet encryption with local CFB mode
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func encrypt(block cipher.Block, dst, src, buf []byte) {
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switch block.BlockSize() {
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case 8:
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encrypt8(block, dst, src, buf)
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case 16:
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encrypt16(block, dst, src, buf)
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default:
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panic("unsupported cipher block size")
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}
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}
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// optimized encryption for the ciphers which works in 8-bytes
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func encrypt8(block cipher.Block, dst, src, buf []byte) {
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tbl := buf[:8]
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block.Encrypt(tbl, initialVector)
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n := len(src) / 8
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base := 0
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repeat := n / 8
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left := n % 8
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ptr_tbl := (*uint64)(unsafe.Pointer(&tbl[0]))
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for i := 0; i < repeat; i++ {
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s := src[base:][0:64]
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d := dst[base:][0:64]
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// 1
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*(*uint64)(unsafe.Pointer(&d[0])) = *(*uint64)(unsafe.Pointer(&s[0])) ^ *ptr_tbl
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block.Encrypt(tbl, d[0:8])
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// 2
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*(*uint64)(unsafe.Pointer(&d[8])) = *(*uint64)(unsafe.Pointer(&s[8])) ^ *ptr_tbl
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block.Encrypt(tbl, d[8:16])
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// 3
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*(*uint64)(unsafe.Pointer(&d[16])) = *(*uint64)(unsafe.Pointer(&s[16])) ^ *ptr_tbl
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block.Encrypt(tbl, d[16:24])
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// 4
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*(*uint64)(unsafe.Pointer(&d[24])) = *(*uint64)(unsafe.Pointer(&s[24])) ^ *ptr_tbl
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block.Encrypt(tbl, d[24:32])
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// 5
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*(*uint64)(unsafe.Pointer(&d[32])) = *(*uint64)(unsafe.Pointer(&s[32])) ^ *ptr_tbl
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block.Encrypt(tbl, d[32:40])
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// 6
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*(*uint64)(unsafe.Pointer(&d[40])) = *(*uint64)(unsafe.Pointer(&s[40])) ^ *ptr_tbl
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block.Encrypt(tbl, d[40:48])
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// 7
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*(*uint64)(unsafe.Pointer(&d[48])) = *(*uint64)(unsafe.Pointer(&s[48])) ^ *ptr_tbl
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block.Encrypt(tbl, d[48:56])
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// 8
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*(*uint64)(unsafe.Pointer(&d[56])) = *(*uint64)(unsafe.Pointer(&s[56])) ^ *ptr_tbl
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block.Encrypt(tbl, d[56:64])
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base += 64
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}
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switch left {
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case 7:
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*(*uint64)(unsafe.Pointer(&dst[base])) = *(*uint64)(unsafe.Pointer(&src[base])) ^ *ptr_tbl
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block.Encrypt(tbl, dst[base:])
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base += 8
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fallthrough
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case 6:
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*(*uint64)(unsafe.Pointer(&dst[base])) = *(*uint64)(unsafe.Pointer(&src[base])) ^ *ptr_tbl
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block.Encrypt(tbl, dst[base:])
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base += 8
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fallthrough
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case 5:
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*(*uint64)(unsafe.Pointer(&dst[base])) = *(*uint64)(unsafe.Pointer(&src[base])) ^ *ptr_tbl
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block.Encrypt(tbl, dst[base:])
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base += 8
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fallthrough
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case 4:
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*(*uint64)(unsafe.Pointer(&dst[base])) = *(*uint64)(unsafe.Pointer(&src[base])) ^ *ptr_tbl
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block.Encrypt(tbl, dst[base:])
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base += 8
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fallthrough
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case 3:
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*(*uint64)(unsafe.Pointer(&dst[base])) = *(*uint64)(unsafe.Pointer(&src[base])) ^ *ptr_tbl
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block.Encrypt(tbl, dst[base:])
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base += 8
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fallthrough
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case 2:
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*(*uint64)(unsafe.Pointer(&dst[base])) = *(*uint64)(unsafe.Pointer(&src[base])) ^ *ptr_tbl
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block.Encrypt(tbl, dst[base:])
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base += 8
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fallthrough
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case 1:
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*(*uint64)(unsafe.Pointer(&dst[base])) = *(*uint64)(unsafe.Pointer(&src[base])) ^ *ptr_tbl
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block.Encrypt(tbl, dst[base:])
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base += 8
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fallthrough
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case 0:
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xorBytes(dst[base:], src[base:], tbl)
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}
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}
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// optimized encryption for the ciphers which works in 16-bytes
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func encrypt16(block cipher.Block, dst, src, buf []byte) {
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tbl := buf[:16]
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block.Encrypt(tbl, initialVector)
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n := len(src) / 16
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base := 0
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repeat := n / 8
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left := n % 8
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for i := 0; i < repeat; i++ {
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s := src[base:][0:128]
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d := dst[base:][0:128]
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// 1
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xor.Bytes16Align(d[0:16], s[0:16], tbl)
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block.Encrypt(tbl, d[0:16])
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// 2
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xor.Bytes16Align(d[16:32], s[16:32], tbl)
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block.Encrypt(tbl, d[16:32])
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// 3
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xor.Bytes16Align(d[32:48], s[32:48], tbl)
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block.Encrypt(tbl, d[32:48])
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// 4
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xor.Bytes16Align(d[48:64], s[48:64], tbl)
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block.Encrypt(tbl, d[48:64])
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// 5
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xor.Bytes16Align(d[64:80], s[64:80], tbl)
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block.Encrypt(tbl, d[64:80])
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// 6
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xor.Bytes16Align(d[80:96], s[80:96], tbl)
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block.Encrypt(tbl, d[80:96])
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// 7
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xor.Bytes16Align(d[96:112], s[96:112], tbl)
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block.Encrypt(tbl, d[96:112])
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// 8
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xor.Bytes16Align(d[112:128], s[112:128], tbl)
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block.Encrypt(tbl, d[112:128])
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base += 128
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}
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switch left {
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case 7:
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xor.Bytes16Align(dst[base:], src[base:], tbl)
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block.Encrypt(tbl, dst[base:])
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base += 16
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fallthrough
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case 6:
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xor.Bytes16Align(dst[base:], src[base:], tbl)
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block.Encrypt(tbl, dst[base:])
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base += 16
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fallthrough
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case 5:
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xor.Bytes16Align(dst[base:], src[base:], tbl)
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block.Encrypt(tbl, dst[base:])
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base += 16
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fallthrough
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case 4:
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xor.Bytes16Align(dst[base:], src[base:], tbl)
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block.Encrypt(tbl, dst[base:])
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base += 16
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fallthrough
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case 3:
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xor.Bytes16Align(dst[base:], src[base:], tbl)
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block.Encrypt(tbl, dst[base:])
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base += 16
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fallthrough
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case 2:
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xor.Bytes16Align(dst[base:], src[base:], tbl)
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block.Encrypt(tbl, dst[base:])
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base += 16
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fallthrough
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case 1:
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xor.Bytes16Align(dst[base:], src[base:], tbl)
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block.Encrypt(tbl, dst[base:])
|
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base += 16
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fallthrough
|
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case 0:
|
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xorBytes(dst[base:], src[base:], tbl)
|
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}
|
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}
|
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|
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// decryption
|
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func decrypt(block cipher.Block, dst, src, buf []byte) {
|
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switch block.BlockSize() {
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case 8:
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decrypt8(block, dst, src, buf)
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case 16:
|
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decrypt16(block, dst, src, buf)
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default:
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panic("unsupported cipher block size")
|
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}
|
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}
|
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|
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// decrypt 8 bytes block, all byte slices are supposed to be 64bit aligned
|
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func decrypt8(block cipher.Block, dst, src, buf []byte) {
|
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tbl := buf[0:8]
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next := buf[8:16]
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block.Encrypt(tbl, initialVector)
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n := len(src) / 8
|
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base := 0
|
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repeat := n / 8
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left := n % 8
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ptr_tbl := (*uint64)(unsafe.Pointer(&tbl[0]))
|
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ptr_next := (*uint64)(unsafe.Pointer(&next[0]))
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|
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for i := 0; i < repeat; i++ {
|
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s := src[base:][0:64]
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d := dst[base:][0:64]
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// 1
|
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block.Encrypt(next, s[0:8])
|
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*(*uint64)(unsafe.Pointer(&d[0])) = *(*uint64)(unsafe.Pointer(&s[0])) ^ *ptr_tbl
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// 2
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block.Encrypt(tbl, s[8:16])
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*(*uint64)(unsafe.Pointer(&d[8])) = *(*uint64)(unsafe.Pointer(&s[8])) ^ *ptr_next
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// 3
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block.Encrypt(next, s[16:24])
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*(*uint64)(unsafe.Pointer(&d[16])) = *(*uint64)(unsafe.Pointer(&s[16])) ^ *ptr_tbl
|
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// 4
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block.Encrypt(tbl, s[24:32])
|
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*(*uint64)(unsafe.Pointer(&d[24])) = *(*uint64)(unsafe.Pointer(&s[24])) ^ *ptr_next
|
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// 5
|
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block.Encrypt(next, s[32:40])
|
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*(*uint64)(unsafe.Pointer(&d[32])) = *(*uint64)(unsafe.Pointer(&s[32])) ^ *ptr_tbl
|
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// 6
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block.Encrypt(tbl, s[40:48])
|
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*(*uint64)(unsafe.Pointer(&d[40])) = *(*uint64)(unsafe.Pointer(&s[40])) ^ *ptr_next
|
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// 7
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block.Encrypt(next, s[48:56])
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*(*uint64)(unsafe.Pointer(&d[48])) = *(*uint64)(unsafe.Pointer(&s[48])) ^ *ptr_tbl
|
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// 8
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block.Encrypt(tbl, s[56:64])
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*(*uint64)(unsafe.Pointer(&d[56])) = *(*uint64)(unsafe.Pointer(&s[56])) ^ *ptr_next
|
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base += 64
|
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}
|
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|
|
switch left {
|
|
case 7:
|
|
block.Encrypt(next, src[base:])
|
|
*(*uint64)(unsafe.Pointer(&dst[base])) = *(*uint64)(unsafe.Pointer(&src[base])) ^ *(*uint64)(unsafe.Pointer(&tbl[0]))
|
|
tbl, next = next, tbl
|
|
base += 8
|
|
fallthrough
|
|
case 6:
|
|
block.Encrypt(next, src[base:])
|
|
*(*uint64)(unsafe.Pointer(&dst[base])) = *(*uint64)(unsafe.Pointer(&src[base])) ^ *(*uint64)(unsafe.Pointer(&tbl[0]))
|
|
tbl, next = next, tbl
|
|
base += 8
|
|
fallthrough
|
|
case 5:
|
|
block.Encrypt(next, src[base:])
|
|
*(*uint64)(unsafe.Pointer(&dst[base])) = *(*uint64)(unsafe.Pointer(&src[base])) ^ *(*uint64)(unsafe.Pointer(&tbl[0]))
|
|
tbl, next = next, tbl
|
|
base += 8
|
|
fallthrough
|
|
case 4:
|
|
block.Encrypt(next, src[base:])
|
|
*(*uint64)(unsafe.Pointer(&dst[base])) = *(*uint64)(unsafe.Pointer(&src[base])) ^ *(*uint64)(unsafe.Pointer(&tbl[0]))
|
|
tbl, next = next, tbl
|
|
base += 8
|
|
fallthrough
|
|
case 3:
|
|
block.Encrypt(next, src[base:])
|
|
*(*uint64)(unsafe.Pointer(&dst[base])) = *(*uint64)(unsafe.Pointer(&src[base])) ^ *(*uint64)(unsafe.Pointer(&tbl[0]))
|
|
tbl, next = next, tbl
|
|
base += 8
|
|
fallthrough
|
|
case 2:
|
|
block.Encrypt(next, src[base:])
|
|
*(*uint64)(unsafe.Pointer(&dst[base])) = *(*uint64)(unsafe.Pointer(&src[base])) ^ *(*uint64)(unsafe.Pointer(&tbl[0]))
|
|
tbl, next = next, tbl
|
|
base += 8
|
|
fallthrough
|
|
case 1:
|
|
block.Encrypt(next, src[base:])
|
|
*(*uint64)(unsafe.Pointer(&dst[base])) = *(*uint64)(unsafe.Pointer(&src[base])) ^ *(*uint64)(unsafe.Pointer(&tbl[0]))
|
|
tbl, next = next, tbl
|
|
base += 8
|
|
fallthrough
|
|
case 0:
|
|
xorBytes(dst[base:], src[base:], tbl)
|
|
}
|
|
}
|
|
|
|
func decrypt16(block cipher.Block, dst, src, buf []byte) {
|
|
tbl := buf[0:16]
|
|
next := buf[16:32]
|
|
block.Encrypt(tbl, initialVector)
|
|
n := len(src) / 16
|
|
base := 0
|
|
repeat := n / 8
|
|
left := n % 8
|
|
for i := 0; i < repeat; i++ {
|
|
s := src[base:][0:128]
|
|
d := dst[base:][0:128]
|
|
// 1
|
|
block.Encrypt(next, s[0:16])
|
|
xor.Bytes16Align(d[0:16], s[0:16], tbl)
|
|
// 2
|
|
block.Encrypt(tbl, s[16:32])
|
|
xor.Bytes16Align(d[16:32], s[16:32], next)
|
|
// 3
|
|
block.Encrypt(next, s[32:48])
|
|
xor.Bytes16Align(d[32:48], s[32:48], tbl)
|
|
// 4
|
|
block.Encrypt(tbl, s[48:64])
|
|
xor.Bytes16Align(d[48:64], s[48:64], next)
|
|
// 5
|
|
block.Encrypt(next, s[64:80])
|
|
xor.Bytes16Align(d[64:80], s[64:80], tbl)
|
|
// 6
|
|
block.Encrypt(tbl, s[80:96])
|
|
xor.Bytes16Align(d[80:96], s[80:96], next)
|
|
// 7
|
|
block.Encrypt(next, s[96:112])
|
|
xor.Bytes16Align(d[96:112], s[96:112], tbl)
|
|
// 8
|
|
block.Encrypt(tbl, s[112:128])
|
|
xor.Bytes16Align(d[112:128], s[112:128], next)
|
|
base += 128
|
|
}
|
|
|
|
switch left {
|
|
case 7:
|
|
block.Encrypt(next, src[base:])
|
|
xor.Bytes16Align(dst[base:], src[base:], tbl)
|
|
tbl, next = next, tbl
|
|
base += 16
|
|
fallthrough
|
|
case 6:
|
|
block.Encrypt(next, src[base:])
|
|
xor.Bytes16Align(dst[base:], src[base:], tbl)
|
|
tbl, next = next, tbl
|
|
base += 16
|
|
fallthrough
|
|
case 5:
|
|
block.Encrypt(next, src[base:])
|
|
xor.Bytes16Align(dst[base:], src[base:], tbl)
|
|
tbl, next = next, tbl
|
|
base += 16
|
|
fallthrough
|
|
case 4:
|
|
block.Encrypt(next, src[base:])
|
|
xor.Bytes16Align(dst[base:], src[base:], tbl)
|
|
tbl, next = next, tbl
|
|
base += 16
|
|
fallthrough
|
|
case 3:
|
|
block.Encrypt(next, src[base:])
|
|
xor.Bytes16Align(dst[base:], src[base:], tbl)
|
|
tbl, next = next, tbl
|
|
base += 16
|
|
fallthrough
|
|
case 2:
|
|
block.Encrypt(next, src[base:])
|
|
xor.Bytes16Align(dst[base:], src[base:], tbl)
|
|
tbl, next = next, tbl
|
|
base += 16
|
|
fallthrough
|
|
case 1:
|
|
block.Encrypt(next, src[base:])
|
|
xor.Bytes16Align(dst[base:], src[base:], tbl)
|
|
tbl, next = next, tbl
|
|
base += 16
|
|
fallthrough
|
|
case 0:
|
|
xorBytes(dst[base:], src[base:], tbl)
|
|
}
|
|
}
|
|
|
|
// per bytes xors
|
|
func xorBytes(dst, a, b []byte) int {
|
|
n := len(a)
|
|
if len(b) < n {
|
|
n = len(b)
|
|
}
|
|
if n == 0 {
|
|
return 0
|
|
}
|
|
|
|
for i := 0; i < n; i++ {
|
|
dst[i] = a[i] ^ b[i]
|
|
}
|
|
return n
|
|
}
|