diff --git a/CONTRIBUTORS b/CONTRIBUTORS index 0f08c55aae..823561cb11 100644 --- a/CONTRIBUTORS +++ b/CONTRIBUTORS @@ -68,6 +68,7 @@ Corey Thomasson Dan Sinclair Daniel Fleischman Daniel Nadasi +Berengar Lehr Daniel Theophanes David G. Andersen David Symonds diff --git a/src/pkg/Makefile b/src/pkg/Makefile index 7582aba3de..05e2a26d1f 100644 --- a/src/pkg/Makefile +++ b/src/pkg/Makefile @@ -47,6 +47,7 @@ DIRS=\ crypto/sha512\ crypto/subtle\ crypto/tls\ + crypto/twofish\ crypto/x509\ crypto/xtea\ debug/dwarf\ diff --git a/src/pkg/crypto/twofish/Makefile b/src/pkg/crypto/twofish/Makefile new file mode 100644 index 0000000000..aec61659d7 --- /dev/null +++ b/src/pkg/crypto/twofish/Makefile @@ -0,0 +1,11 @@ +# Copyright 2011 The Go Authors. All rights reserved. +# Use of this source code is governed by a BSD-style +# license that can be found in the LICENSE file. + +include ../../../Make.inc + +TARG=crypto/twofish +GOFILES=\ + twofish.go\ + +include ../../../Make.pkg diff --git a/src/pkg/crypto/twofish/twofish.go b/src/pkg/crypto/twofish/twofish.go new file mode 100644 index 0000000000..b362c44d29 --- /dev/null +++ b/src/pkg/crypto/twofish/twofish.go @@ -0,0 +1,358 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// This package implements Bruce Schneier's Twofish encryption algorithm. +package twofish + +// Twofish is defined in http://www.schneier.com/paper-twofish-paper.pdf [TWOFISH] + +// This code is a port of the LibTom C implementation. +// See http://libtom.org/?page=features&newsitems=5&whatfile=crypt. +// LibTomCrypt is free for all purposes under the public domain. +// It was heavily inspired by the go blowfish package. + +import ( + "os" + "strconv" +) + +// BlockSize is the constant block size of Twofish. +const BlockSize = 16 + +const mdsPolynomial = 0x169 // x^8 + x^6 + x^5 + x^3 + 1, see [TWOFISH] 4.2 +const rsPolynomial = 0x14d // x^8 + x^6 + x^3 + x^2 + 1, see [TWOFISH] 4.3 + +// A Cipher is an instance of Twofish encryption using a particular key. +type Cipher struct { + s [4][256]uint32 + k [40]uint32 +} + +type KeySizeError int + +func (k KeySizeError) String() string { + return "crypto/twofish: invalid key size " + strconv.Itoa(int(k)) +} + +// NewCipher creates and returns a Cipher. +// The key argument should be the Twofish key, 16, 24 or 32 bytes. +func NewCipher(key []byte) (*Cipher, os.Error) { + keylen := len(key) + + if keylen != 16 && keylen != 24 && keylen != 32 { + return nil, KeySizeError(keylen) + } + + // k is the number of 64 bit words in key + k := keylen / 8 + + // Create the S[..] words + var S [4 * 4]byte + for i := 0; i < k; i++ { + // Computes [y0 y1 y2 y3] = rs . [x0 x1 x2 x3 x4 x5 x6 x7] + for j := 0; j < 4; j++ { + for k := 0; k < 8; k++ { + S[4*i+j] ^= gfMult(key[8*i+k], rs[j][k], rsPolynomial) + } + } + } + + // Calculate subkeys + c := new(Cipher) + var tmp [4]byte + for i := byte(0); i < 20; i++ { + // A = h(p * 2x, Me) + for j := 0; j < 4; j++ { + tmp[j] = 2 * i + } + A := h(tmp[:], key, 0) + + // B = rolc(h(p * (2x + 1), Mo), 8) + for j := 0; j < 4; j++ { + tmp[j] = 2*i + 1 + } + B := h(tmp[:], key, 1) + B = rol(B, 8) + + c.k[2*i] = A + B + + // K[2i+1] = (A + 2B) <<< 9 + c.k[2*i+1] = rol(2*B+A, 9) + } + + // Calculate sboxes + switch k { + case 2: + for i := 0; i <= 255; i++ { + c.s[0][i] = mdsColumnMult(sbox[1][sbox[0][sbox[0][byte(i)]^S[0]]^S[4]], 0) + c.s[1][i] = mdsColumnMult(sbox[0][sbox[0][sbox[1][byte(i)]^S[1]]^S[5]], 1) + c.s[2][i] = mdsColumnMult(sbox[1][sbox[1][sbox[0][byte(i)]^S[2]]^S[6]], 2) + c.s[3][i] = mdsColumnMult(sbox[0][sbox[1][sbox[1][byte(i)]^S[3]]^S[7]], 3) + } + case 3: + for i := 0; i < 256; i++ { + c.s[0][i] = mdsColumnMult(sbox[1][sbox[0][sbox[0][sbox[1][byte(i)]^S[0]]^S[4]]^S[8]], 0) + c.s[1][i] = mdsColumnMult(sbox[0][sbox[0][sbox[1][sbox[1][byte(i)]^S[1]]^S[5]]^S[9]], 1) + c.s[2][i] = mdsColumnMult(sbox[1][sbox[1][sbox[0][sbox[0][byte(i)]^S[2]]^S[6]]^S[10]], 2) + c.s[3][i] = mdsColumnMult(sbox[0][sbox[1][sbox[1][sbox[0][byte(i)]^S[3]]^S[7]]^S[11]], 3) + } + default: + for i := 0; i < 256; i++ { + c.s[0][i] = mdsColumnMult(sbox[1][sbox[0][sbox[0][sbox[1][sbox[1][byte(i)]^S[0]]^S[4]]^S[8]]^S[12]], 0) + c.s[1][i] = mdsColumnMult(sbox[0][sbox[0][sbox[1][sbox[1][sbox[0][byte(i)]^S[1]]^S[5]]^S[9]]^S[13]], 1) + c.s[2][i] = mdsColumnMult(sbox[1][sbox[1][sbox[0][sbox[0][sbox[0][byte(i)]^S[2]]^S[6]]^S[10]]^S[14]], 2) + c.s[3][i] = mdsColumnMult(sbox[0][sbox[1][sbox[1][sbox[0][sbox[1][byte(i)]^S[3]]^S[7]]^S[11]]^S[15]], 3) + } + } + + return c, nil +} + +// Reset zeros the key data, so that it will no longer appear in the process's +// memory. +func (c *Cipher) Reset() { + for i := 0; i < 40; i++ { + c.k[i] = 0 + } + for i := 0; i < 4; i++ { + for j := 0; j < 265; j++ { + c.s[i][j] = 0 + } + } +} + +// BlockSize returns the Twofish block size, 16 bytes. +func (c *Cipher) BlockSize() int { return BlockSize } + +// store32l stores src in dst in little-endian form. +func store32l(dst []byte, src uint32) { + dst[0] = byte(src) + dst[1] = byte(src >> 8) + dst[2] = byte(src >> 16) + dst[3] = byte(src >> 24) + return +} + +// load32l reads a little-endian uint32 from src. +func load32l(src []byte) uint32 { + return uint32(src[0]) | uint32(src[1])<<8 | uint32(src[2])<<16 | uint32(src[3])<<24 +} + +// rol returns x after a left circular rotation of y bits. +func rol(x, y uint32) uint32 { + return (x << (y & 31)) | (x >> (32 - (y & 31))) +} + +// ror returns x after a right circular rotation of y bits. +func ror(x, y uint32) uint32 { + return (x >> (y & 31)) | (x << (32 - (y & 31))) +} + +// The RS matrix. See [TWOFISH] 4.3 +var rs = [4][8]byte{ + {0x01, 0xA4, 0x55, 0x87, 0x5A, 0x58, 0xDB, 0x9E}, + {0xA4, 0x56, 0x82, 0xF3, 0x1E, 0xC6, 0x68, 0xE5}, + {0x02, 0xA1, 0xFC, 0xC1, 0x47, 0xAE, 0x3D, 0x19}, + {0xA4, 0x55, 0x87, 0x5A, 0x58, 0xDB, 0x9E, 0x03}, +} + +// sbox tables +var sbox = [2][256]byte{ + { + 0xa9, 0x67, 0xb3, 0xe8, 0x04, 0xfd, 0xa3, 0x76, 0x9a, 0x92, 0x80, 0x78, 0xe4, 0xdd, 0xd1, 0x38, + 0x0d, 0xc6, 0x35, 0x98, 0x18, 0xf7, 0xec, 0x6c, 0x43, 0x75, 0x37, 0x26, 0xfa, 0x13, 0x94, 0x48, + 0xf2, 0xd0, 0x8b, 0x30, 0x84, 0x54, 0xdf, 0x23, 0x19, 0x5b, 0x3d, 0x59, 0xf3, 0xae, 0xa2, 0x82, + 0x63, 0x01, 0x83, 0x2e, 0xd9, 0x51, 0x9b, 0x7c, 0xa6, 0xeb, 0xa5, 0xbe, 0x16, 0x0c, 0xe3, 0x61, + 0xc0, 0x8c, 0x3a, 0xf5, 0x73, 0x2c, 0x25, 0x0b, 0xbb, 0x4e, 0x89, 0x6b, 0x53, 0x6a, 0xb4, 0xf1, + 0xe1, 0xe6, 0xbd, 0x45, 0xe2, 0xf4, 0xb6, 0x66, 0xcc, 0x95, 0x03, 0x56, 0xd4, 0x1c, 0x1e, 0xd7, + 0xfb, 0xc3, 0x8e, 0xb5, 0xe9, 0xcf, 0xbf, 0xba, 0xea, 0x77, 0x39, 0xaf, 0x33, 0xc9, 0x62, 0x71, + 0x81, 0x79, 0x09, 0xad, 0x24, 0xcd, 0xf9, 0xd8, 0xe5, 0xc5, 0xb9, 0x4d, 0x44, 0x08, 0x86, 0xe7, + 0xa1, 0x1d, 0xaa, 0xed, 0x06, 0x70, 0xb2, 0xd2, 0x41, 0x7b, 0xa0, 0x11, 0x31, 0xc2, 0x27, 0x90, + 0x20, 0xf6, 0x60, 0xff, 0x96, 0x5c, 0xb1, 0xab, 0x9e, 0x9c, 0x52, 0x1b, 0x5f, 0x93, 0x0a, 0xef, + 0x91, 0x85, 0x49, 0xee, 0x2d, 0x4f, 0x8f, 0x3b, 0x47, 0x87, 0x6d, 0x46, 0xd6, 0x3e, 0x69, 0x64, + 0x2a, 0xce, 0xcb, 0x2f, 0xfc, 0x97, 0x05, 0x7a, 0xac, 0x7f, 0xd5, 0x1a, 0x4b, 0x0e, 0xa7, 0x5a, + 0x28, 0x14, 0x3f, 0x29, 0x88, 0x3c, 0x4c, 0x02, 0xb8, 0xda, 0xb0, 0x17, 0x55, 0x1f, 0x8a, 0x7d, + 0x57, 0xc7, 0x8d, 0x74, 0xb7, 0xc4, 0x9f, 0x72, 0x7e, 0x15, 0x22, 0x12, 0x58, 0x07, 0x99, 0x34, + 0x6e, 0x50, 0xde, 0x68, 0x65, 0xbc, 0xdb, 0xf8, 0xc8, 0xa8, 0x2b, 0x40, 0xdc, 0xfe, 0x32, 0xa4, + 0xca, 0x10, 0x21, 0xf0, 0xd3, 0x5d, 0x0f, 0x00, 0x6f, 0x9d, 0x36, 0x42, 0x4a, 0x5e, 0xc1, 0xe0, + }, + { + 0x75, 0xf3, 0xc6, 0xf4, 0xdb, 0x7b, 0xfb, 0xc8, 0x4a, 0xd3, 0xe6, 0x6b, 0x45, 0x7d, 0xe8, 0x4b, + 0xd6, 0x32, 0xd8, 0xfd, 0x37, 0x71, 0xf1, 0xe1, 0x30, 0x0f, 0xf8, 0x1b, 0x87, 0xfa, 0x06, 0x3f, + 0x5e, 0xba, 0xae, 0x5b, 0x8a, 0x00, 0xbc, 0x9d, 0x6d, 0xc1, 0xb1, 0x0e, 0x80, 0x5d, 0xd2, 0xd5, + 0xa0, 0x84, 0x07, 0x14, 0xb5, 0x90, 0x2c, 0xa3, 0xb2, 0x73, 0x4c, 0x54, 0x92, 0x74, 0x36, 0x51, + 0x38, 0xb0, 0xbd, 0x5a, 0xfc, 0x60, 0x62, 0x96, 0x6c, 0x42, 0xf7, 0x10, 0x7c, 0x28, 0x27, 0x8c, + 0x13, 0x95, 0x9c, 0xc7, 0x24, 0x46, 0x3b, 0x70, 0xca, 0xe3, 0x85, 0xcb, 0x11, 0xd0, 0x93, 0xb8, + 0xa6, 0x83, 0x20, 0xff, 0x9f, 0x77, 0xc3, 0xcc, 0x03, 0x6f, 0x08, 0xbf, 0x40, 0xe7, 0x2b, 0xe2, + 0x79, 0x0c, 0xaa, 0x82, 0x41, 0x3a, 0xea, 0xb9, 0xe4, 0x9a, 0xa4, 0x97, 0x7e, 0xda, 0x7a, 0x17, + 0x66, 0x94, 0xa1, 0x1d, 0x3d, 0xf0, 0xde, 0xb3, 0x0b, 0x72, 0xa7, 0x1c, 0xef, 0xd1, 0x53, 0x3e, + 0x8f, 0x33, 0x26, 0x5f, 0xec, 0x76, 0x2a, 0x49, 0x81, 0x88, 0xee, 0x21, 0xc4, 0x1a, 0xeb, 0xd9, + 0xc5, 0x39, 0x99, 0xcd, 0xad, 0x31, 0x8b, 0x01, 0x18, 0x23, 0xdd, 0x1f, 0x4e, 0x2d, 0xf9, 0x48, + 0x4f, 0xf2, 0x65, 0x8e, 0x78, 0x5c, 0x58, 0x19, 0x8d, 0xe5, 0x98, 0x57, 0x67, 0x7f, 0x05, 0x64, + 0xaf, 0x63, 0xb6, 0xfe, 0xf5, 0xb7, 0x3c, 0xa5, 0xce, 0xe9, 0x68, 0x44, 0xe0, 0x4d, 0x43, 0x69, + 0x29, 0x2e, 0xac, 0x15, 0x59, 0xa8, 0x0a, 0x9e, 0x6e, 0x47, 0xdf, 0x34, 0x35, 0x6a, 0xcf, 0xdc, + 0x22, 0xc9, 0xc0, 0x9b, 0x89, 0xd4, 0xed, 0xab, 0x12, 0xa2, 0x0d, 0x52, 0xbb, 0x02, 0x2f, 0xa9, + 0xd7, 0x61, 0x1e, 0xb4, 0x50, 0x04, 0xf6, 0xc2, 0x16, 0x25, 0x86, 0x56, 0x55, 0x09, 0xbe, 0x91, + }, +} + +// gfMult returns a·b in GF(2^8)/p +func gfMult(a, b byte, p uint32) byte { + B := [2]uint32{0, uint32(b)} + P := [2]uint32{0, p} + var result uint32 + + // branchless GF multiplier + for i := 0; i < 7; i++ { + result ^= B[a&1] + a >>= 1 + B[1] = P[B[1]>>7] ^ (B[1] << 1) + } + result ^= B[a&1] + return byte(result) +} + +// mdsColumnMult calculates y{col} where [y0 y1 y2 y3] = MDS . [x0] +func mdsColumnMult(in byte, col int) uint32 { + mul01 := in + mul5B := gfMult(in, 0x5B, mdsPolynomial) + mulEF := gfMult(in, 0xEF, mdsPolynomial) + + switch col { + case 0: + return uint32(mul01) | uint32(mul5B)<<8 | uint32(mulEF)<<16 | uint32(mulEF)<<24 + case 1: + return uint32(mulEF) | uint32(mulEF)<<8 | uint32(mul5B)<<16 | uint32(mul01)<<24 + case 2: + return uint32(mul5B) | uint32(mulEF)<<8 | uint32(mul01)<<16 | uint32(mulEF)<<24 + case 3: + return uint32(mul5B) | uint32(mul01)<<8 | uint32(mulEF)<<16 | uint32(mul5B)<<24 + } + + panic("unreachable") +} + +// h implements the S-box generation function. See [TWOFISH] 4.3.5 +func h(in, key []byte, offset int) uint32 { + var y [4]byte + for x := 0; x < 4; x++ { + y[x] = in[x] + } + switch len(key) / 8 { + case 4: + y[0] = sbox[1][y[0]] ^ key[4*(6+offset)+0] + y[1] = sbox[0][y[1]] ^ key[4*(6+offset)+1] + y[2] = sbox[0][y[2]] ^ key[4*(6+offset)+2] + y[3] = sbox[1][y[3]] ^ key[4*(6+offset)+3] + fallthrough + case 3: + y[0] = sbox[1][y[0]] ^ key[4*(4+offset)+0] + y[1] = sbox[1][y[1]] ^ key[4*(4+offset)+1] + y[2] = sbox[0][y[2]] ^ key[4*(4+offset)+2] + y[3] = sbox[0][y[3]] ^ key[4*(4+offset)+3] + fallthrough + case 2: + y[0] = sbox[1][sbox[0][sbox[0][y[0]]^key[4*(2+offset)+0]]^key[4*(0+offset)+0]] + y[1] = sbox[0][sbox[0][sbox[1][y[1]]^key[4*(2+offset)+1]]^key[4*(0+offset)+1]] + y[2] = sbox[1][sbox[1][sbox[0][y[2]]^key[4*(2+offset)+2]]^key[4*(0+offset)+2]] + y[3] = sbox[0][sbox[1][sbox[1][y[3]]^key[4*(2+offset)+3]]^key[4*(0+offset)+3]] + } + // [y0 y1 y2 y3] = MDS . [x0 x1 x2 x3] + var mdsMult uint32 + for i := 0; i < 4; i++ { + mdsMult ^= mdsColumnMult(y[i], i) + } + return mdsMult +} + +// Encrypt encrypts a 16-byte block from src to dst, which may overlap. +// Note that for amounts of data larger than a block, +// it is not safe to just call Encrypt on successive blocks; +// instead, use an encryption mode like CBC (see crypto/block/cbc.go). +func (skey *Cipher) Encrypt(dst, src []byte) { + S1 := skey.s[0] + S2 := skey.s[1] + S3 := skey.s[2] + S4 := skey.s[3] + + // Load input + a := load32l(src[0:4]) + b := load32l(src[4:8]) + c := load32l(src[8:12]) + d := load32l(src[12:16]) + + // Pre-whitening + a ^= skey.k[0] + b ^= skey.k[1] + c ^= skey.k[2] + d ^= skey.k[3] + + for i := 0; i < 8; i++ { + k := skey.k[8+i*4 : 12+i*4] + t2 := S2[byte(b)] ^ S3[byte(b>>8)] ^ S4[byte(b>>16)] ^ S1[byte(b>>24)] + t1 := S1[byte(a)] ^ S2[byte(a>>8)] ^ S3[byte(a>>16)] ^ S4[byte(a>>24)] + t2 + c = ror(c^(t1+k[0]), 1) + d = rol(d, 1) ^ (t2 + t1 + k[1]) + + t2 = S2[byte(d)] ^ S3[byte(d>>8)] ^ S4[byte(d>>16)] ^ S1[byte(d>>24)] + t1 = S1[byte(c)] ^ S2[byte(c>>8)] ^ S3[byte(c>>16)] ^ S4[byte(c>>24)] + t2 + a = ror(a^(t1+k[2]), 1) + b = rol(b, 1) ^ (t2 + t1 + k[3]) + } + + // Output with "undo last swap" + ta := c ^ skey.k[4] + tb := d ^ skey.k[5] + tc := a ^ skey.k[6] + td := b ^ skey.k[7] + + store32l(dst[0:4], ta) + store32l(dst[4:8], tb) + store32l(dst[8:12], tc) + store32l(dst[12:16], td) +} + +// Decrypt decrypts a 16-byte block from src to dst, which may overlap. +func (skey *Cipher) Decrypt(dst, src []byte) { + S1 := skey.s[0] + S2 := skey.s[1] + S3 := skey.s[2] + S4 := skey.s[3] + + // Load input + ta := load32l(src[0:4]) + tb := load32l(src[4:8]) + tc := load32l(src[8:12]) + td := load32l(src[12:16]) + + // Undo undo final swap + a := tc ^ skey.k[6] + b := td ^ skey.k[7] + c := ta ^ skey.k[4] + d := tb ^ skey.k[5] + + for i := 8; i > 0; i-- { + k := skey.k[4+i*4 : 8+i*4] + t2 := S2[byte(d)] ^ S3[byte(d>>8)] ^ S4[byte(d>>16)] ^ S1[byte(d>>24)] + t1 := S1[byte(c)] ^ S2[byte(c>>8)] ^ S3[byte(c>>16)] ^ S4[byte(c>>24)] + t2 + a = rol(a, 1) ^ (t1 + k[2]) + b = ror(b^(t2+t1+k[3]), 1) + + t2 = S2[byte(b)] ^ S3[byte(b>>8)] ^ S4[byte(b>>16)] ^ S1[byte(b>>24)] + t1 = S1[byte(a)] ^ S2[byte(a>>8)] ^ S3[byte(a>>16)] ^ S4[byte(a>>24)] + t2 + c = rol(c, 1) ^ (t1 + k[0]) + d = ror(d^(t2+t1+k[1]), 1) + } + + // Undo pre-whitening + a ^= skey.k[0] + b ^= skey.k[1] + c ^= skey.k[2] + d ^= skey.k[3] + + store32l(dst[0:4], a) + store32l(dst[4:8], b) + store32l(dst[8:12], c) + store32l(dst[12:16], d) +} diff --git a/src/pkg/crypto/twofish/twofish_test.go b/src/pkg/crypto/twofish/twofish_test.go new file mode 100644 index 0000000000..96ca6797a4 --- /dev/null +++ b/src/pkg/crypto/twofish/twofish_test.go @@ -0,0 +1,129 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package twofish + +import ( + "bytes" + "testing" +) + +var qbox = [2][4][16]byte{ + { + {0x8, 0x1, 0x7, 0xD, 0x6, 0xF, 0x3, 0x2, 0x0, 0xB, 0x5, 0x9, 0xE, 0xC, 0xA, 0x4}, + {0xE, 0xC, 0xB, 0x8, 0x1, 0x2, 0x3, 0x5, 0xF, 0x4, 0xA, 0x6, 0x7, 0x0, 0x9, 0xD}, + {0xB, 0xA, 0x5, 0xE, 0x6, 0xD, 0x9, 0x0, 0xC, 0x8, 0xF, 0x3, 0x2, 0x4, 0x7, 0x1}, + {0xD, 0x7, 0xF, 0x4, 0x1, 0x2, 0x6, 0xE, 0x9, 0xB, 0x3, 0x0, 0x8, 0x5, 0xC, 0xA}, + }, + { + {0x2, 0x8, 0xB, 0xD, 0xF, 0x7, 0x6, 0xE, 0x3, 0x1, 0x9, 0x4, 0x0, 0xA, 0xC, 0x5}, + {0x1, 0xE, 0x2, 0xB, 0x4, 0xC, 0x3, 0x7, 0x6, 0xD, 0xA, 0x5, 0xF, 0x9, 0x0, 0x8}, + {0x4, 0xC, 0x7, 0x5, 0x1, 0x6, 0x9, 0xA, 0x0, 0xE, 0xD, 0x8, 0x2, 0xB, 0x3, 0xF}, + {0xB, 0x9, 0x5, 0x1, 0xC, 0x3, 0xD, 0xE, 0x6, 0x4, 0x7, 0xF, 0x2, 0x0, 0x8, 0xA}, + }, +} + +// genSbox generates the variable sbox +func genSbox(qi int, x byte) byte { + a0, b0 := x/16, x%16 + for i := 0; i < 2; i++ { + a1 := a0 ^ b0 + b1 := (a0 ^ ((b0 << 3) | (b0 >> 1)) ^ (a0 << 3)) & 15 + a0 = qbox[qi][2*i][a1] + b0 = qbox[qi][2*i+1][b1] + } + return (b0 << 4) + a0 +} + +func TestSbox(t *testing.T) { + for n := 0; n < 2; n++ { + for m := 0; m < 256; m++ { + if genSbox(n, byte(m)) != sbox[n][m] { + t.Errorf("#%d|%d: sbox value = %d want %d", n, m, sbox[n][m], genSbox(n, byte(m))) + } + } + } +} + +var testVectors = []struct { + key []byte + dec []byte + enc []byte +}{ + // These tests are extracted from LibTom + { + []byte{0x9F, 0x58, 0x9F, 0x5C, 0xF6, 0x12, 0x2C, 0x32, 0xB6, 0xBF, 0xEC, 0x2F, 0x2A, 0xE8, 0xC3, 0x5A}, + []byte{0xD4, 0x91, 0xDB, 0x16, 0xE7, 0xB1, 0xC3, 0x9E, 0x86, 0xCB, 0x08, 0x6B, 0x78, 0x9F, 0x54, 0x19}, + []byte{0x01, 0x9F, 0x98, 0x09, 0xDE, 0x17, 0x11, 0x85, 0x8F, 0xAA, 0xC3, 0xA3, 0xBA, 0x20, 0xFB, 0xC3}, + }, + { + []byte{0x88, 0xB2, 0xB2, 0x70, 0x6B, 0x10, 0x5E, 0x36, 0xB4, 0x46, 0xBB, 0x6D, 0x73, 0x1A, 0x1E, 0x88, + 0xEF, 0xA7, 0x1F, 0x78, 0x89, 0x65, 0xBD, 0x44}, + []byte{0x39, 0xDA, 0x69, 0xD6, 0xBA, 0x49, 0x97, 0xD5, 0x85, 0xB6, 0xDC, 0x07, 0x3C, 0xA3, 0x41, 0xB2}, + []byte{0x18, 0x2B, 0x02, 0xD8, 0x14, 0x97, 0xEA, 0x45, 0xF9, 0xDA, 0xAC, 0xDC, 0x29, 0x19, 0x3A, 0x65}, + }, + { + []byte{0xD4, 0x3B, 0xB7, 0x55, 0x6E, 0xA3, 0x2E, 0x46, 0xF2, 0xA2, 0x82, 0xB7, 0xD4, 0x5B, 0x4E, 0x0D, + 0x57, 0xFF, 0x73, 0x9D, 0x4D, 0xC9, 0x2C, 0x1B, 0xD7, 0xFC, 0x01, 0x70, 0x0C, 0xC8, 0x21, 0x6F}, + []byte{0x90, 0xAF, 0xE9, 0x1B, 0xB2, 0x88, 0x54, 0x4F, 0x2C, 0x32, 0xDC, 0x23, 0x9B, 0x26, 0x35, 0xE6}, + []byte{0x6C, 0xB4, 0x56, 0x1C, 0x40, 0xBF, 0x0A, 0x97, 0x05, 0x93, 0x1C, 0xB6, 0xD4, 0x08, 0xE7, 0xFA}, + }, + // These test are derived from http://www.schneier.com/code/ecb_ival.txt + { + []byte{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}, + []byte{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}, + []byte{0x9F, 0x58, 0x9F, 0x5C, 0xF6, 0x12, 0x2C, 0x32, 0xB6, 0xBF, 0xEC, 0x2F, 0x2A, 0xE8, 0xC3, 0x5A}, + }, + { + []byte{0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF, 0xFE, 0xDC, 0xBA, 0x98, 0x76, 0x54, 0x32, 0x10, + 0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, + }, + []byte{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}, + []byte{0xCF, 0xD1, 0xD2, 0xE5, 0xA9, 0xBE, 0x9C, 0xDF, 0x50, 0x1F, 0x13, 0xB8, 0x92, 0xBD, 0x22, 0x48}, + }, + { + []byte{0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF, 0xFE, 0xDC, 0xBA, 0x98, 0x76, 0x54, 0x32, 0x10, + 0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88, 0x99, 0xAA, 0xBB, 0xCC, 0xDD, 0xEE, 0xFF, + }, + []byte{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}, + []byte{0x37, 0x52, 0x7B, 0xE0, 0x05, 0x23, 0x34, 0xB8, 0x9F, 0x0C, 0xFC, 0xCA, 0xE8, 0x7C, 0xFA, 0x20}, + }, +} + +func TestCipher(t *testing.T) { + for n, tt := range testVectors { + // Test if the plaintext (dec) is encrypts to the given + // ciphertext (enc) using the given key. Test also if enc can + // be decrypted again into dec. + c, err := NewCipher(tt.key) + if err != nil { + t.Errorf("#%d: NewCipher: %v", n, err) + return + } + + buf := make([]byte, 16) + c.Encrypt(buf, tt.dec) + if !bytes.Equal(buf, tt.enc) { + t.Errorf("#%d: encrypt = %x want %x", n, buf, tt.enc) + } + c.Decrypt(buf, tt.enc) + if !bytes.Equal(buf, tt.dec) { + t.Errorf("#%d: decrypt = %x want %x", n, buf, tt.dec) + } + + // Test that 16 zero bytes, encrypted 1000 times then decrypted + // 1000 times results in zero bytes again. + zero := make([]byte, 16) + buf = make([]byte, 16) + for i := 0; i < 1000; i++ { + c.Encrypt(buf, buf) + } + for i := 0; i < 1000; i++ { + c.Decrypt(buf, buf) + } + if !bytes.Equal(buf, zero) { + t.Errorf("#%d: encrypt/decrypt 1000: have %x want %x", n, buf, zero) + } + } +}