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authorlloyd <[email protected]>2014-01-10 03:41:59 +0000
committerlloyd <[email protected]>2014-01-10 03:41:59 +0000
commit6894dca64c04936d07048c0e8cbf7e25858548c3 (patch)
tree5d572bfde9fe667dab14e3f04b5285a85d8acd95 /src/lib/block/twofish/twofish.cpp
parent9efa3be92442afb3d0b69890a36c7f122df18eda (diff)
Move lib into src
Diffstat (limited to 'src/lib/block/twofish/twofish.cpp')
-rw-r--r--src/lib/block/twofish/twofish.cpp245
1 files changed, 245 insertions, 0 deletions
diff --git a/src/lib/block/twofish/twofish.cpp b/src/lib/block/twofish/twofish.cpp
new file mode 100644
index 000000000..4ea8a799e
--- /dev/null
+++ b/src/lib/block/twofish/twofish.cpp
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+/*
+* Twofish
+* (C) 1999-2007 Jack Lloyd
+*
+* The key schedule implemenation is based on a public domain
+* implementation by Matthew Skala
+*
+* Distributed under the terms of the Botan license
+*/
+
+#include <botan/twofish.h>
+#include <botan/loadstor.h>
+#include <botan/rotate.h>
+
+namespace Botan {
+
+/*
+* Twofish Encryption
+*/
+void Twofish::encrypt_n(const byte in[], byte out[], size_t blocks) const
+ {
+ for(size_t i = 0; i != blocks; ++i)
+ {
+ u32bit A = load_le<u32bit>(in, 0) ^ RK[0];
+ u32bit B = load_le<u32bit>(in, 1) ^ RK[1];
+ u32bit C = load_le<u32bit>(in, 2) ^ RK[2];
+ u32bit D = load_le<u32bit>(in, 3) ^ RK[3];
+
+ for(size_t j = 0; j != 16; j += 2)
+ {
+ u32bit X, Y;
+
+ X = SB[ get_byte(3, A)] ^ SB[256+get_byte(2, A)] ^
+ SB[512+get_byte(1, A)] ^ SB[768+get_byte(0, A)];
+ Y = SB[ get_byte(0, B)] ^ SB[256+get_byte(3, B)] ^
+ SB[512+get_byte(2, B)] ^ SB[768+get_byte(1, B)];
+ X += Y;
+ Y += X + RK[2*j + 9];
+ X += RK[2*j + 8];
+
+ C = rotate_right(C ^ X, 1);
+ D = rotate_left(D, 1) ^ Y;
+
+ X = SB[ get_byte(3, C)] ^ SB[256+get_byte(2, C)] ^
+ SB[512+get_byte(1, C)] ^ SB[768+get_byte(0, C)];
+ Y = SB[ get_byte(0, D)] ^ SB[256+get_byte(3, D)] ^
+ SB[512+get_byte(2, D)] ^ SB[768+get_byte(1, D)];
+ X += Y;
+ Y += X + RK[2*j + 11];
+ X += RK[2*j + 10];
+
+ A = rotate_right(A ^ X, 1);
+ B = rotate_left(B, 1) ^ Y;
+ }
+
+ C ^= RK[4];
+ D ^= RK[5];
+ A ^= RK[6];
+ B ^= RK[7];
+
+ store_le(out, C, D, A, B);
+
+ in += BLOCK_SIZE;
+ out += BLOCK_SIZE;
+ }
+ }
+
+/*
+* Twofish Decryption
+*/
+void Twofish::decrypt_n(const byte in[], byte out[], size_t blocks) const
+ {
+ for(size_t i = 0; i != blocks; ++i)
+ {
+ u32bit A = load_le<u32bit>(in, 0) ^ RK[4];
+ u32bit B = load_le<u32bit>(in, 1) ^ RK[5];
+ u32bit C = load_le<u32bit>(in, 2) ^ RK[6];
+ u32bit D = load_le<u32bit>(in, 3) ^ RK[7];
+
+ for(size_t j = 0; j != 16; j += 2)
+ {
+ u32bit X, Y;
+
+ X = SB[ get_byte(3, A)] ^ SB[256+get_byte(2, A)] ^
+ SB[512+get_byte(1, A)] ^ SB[768+get_byte(0, A)];
+ Y = SB[ get_byte(0, B)] ^ SB[256+get_byte(3, B)] ^
+ SB[512+get_byte(2, B)] ^ SB[768+get_byte(1, B)];
+ X += Y;
+ Y += X + RK[39 - 2*j];
+ X += RK[38 - 2*j];
+
+ C = rotate_left(C, 1) ^ X;
+ D = rotate_right(D ^ Y, 1);
+
+ X = SB[ get_byte(3, C)] ^ SB[256+get_byte(2, C)] ^
+ SB[512+get_byte(1, C)] ^ SB[768+get_byte(0, C)];
+ Y = SB[ get_byte(0, D)] ^ SB[256+get_byte(3, D)] ^
+ SB[512+get_byte(2, D)] ^ SB[768+get_byte(1, D)];
+ X += Y;
+ Y += X + RK[37 - 2*j];
+ X += RK[36 - 2*j];
+
+ A = rotate_left(A, 1) ^ X;
+ B = rotate_right(B ^ Y, 1);
+ }
+
+ C ^= RK[0];
+ D ^= RK[1];
+ A ^= RK[2];
+ B ^= RK[3];
+
+ store_le(out, C, D, A, B);
+
+ in += BLOCK_SIZE;
+ out += BLOCK_SIZE;
+ }
+ }
+
+/*
+* Twofish Key Schedule
+*/
+void Twofish::key_schedule(const byte key[], size_t length)
+ {
+ SB.resize(1024);
+ RK.resize(40);
+
+ secure_vector<byte> S(16);
+
+ for(size_t i = 0; i != length; ++i)
+ rs_mul(&S[4*(i/8)], key[i], i);
+
+ if(length == 16)
+ {
+ for(size_t i = 0; i != 256; ++i)
+ {
+ SB[ i] = MDS0[Q0[Q0[i]^S[ 0]]^S[ 4]];
+ SB[256+i] = MDS1[Q0[Q1[i]^S[ 1]]^S[ 5]];
+ SB[512+i] = MDS2[Q1[Q0[i]^S[ 2]]^S[ 6]];
+ SB[768+i] = MDS3[Q1[Q1[i]^S[ 3]]^S[ 7]];
+ }
+
+ for(size_t i = 0; i != 40; i += 2)
+ {
+ u32bit X = MDS0[Q0[Q0[i ]^key[ 8]]^key[ 0]] ^
+ MDS1[Q0[Q1[i ]^key[ 9]]^key[ 1]] ^
+ MDS2[Q1[Q0[i ]^key[10]]^key[ 2]] ^
+ MDS3[Q1[Q1[i ]^key[11]]^key[ 3]];
+ u32bit Y = MDS0[Q0[Q0[i+1]^key[12]]^key[ 4]] ^
+ MDS1[Q0[Q1[i+1]^key[13]]^key[ 5]] ^
+ MDS2[Q1[Q0[i+1]^key[14]]^key[ 6]] ^
+ MDS3[Q1[Q1[i+1]^key[15]]^key[ 7]];
+ Y = rotate_left(Y, 8);
+ X += Y; Y += X;
+
+ RK[i] = X;
+ RK[i+1] = rotate_left(Y, 9);
+ }
+ }
+ else if(length == 24)
+ {
+ for(size_t i = 0; i != 256; ++i)
+ {
+ SB[ i] = MDS0[Q0[Q0[Q1[i]^S[ 0]]^S[ 4]]^S[ 8]];
+ SB[256+i] = MDS1[Q0[Q1[Q1[i]^S[ 1]]^S[ 5]]^S[ 9]];
+ SB[512+i] = MDS2[Q1[Q0[Q0[i]^S[ 2]]^S[ 6]]^S[10]];
+ SB[768+i] = MDS3[Q1[Q1[Q0[i]^S[ 3]]^S[ 7]]^S[11]];
+ }
+
+ for(size_t i = 0; i != 40; i += 2)
+ {
+ u32bit X = MDS0[Q0[Q0[Q1[i ]^key[16]]^key[ 8]]^key[ 0]] ^
+ MDS1[Q0[Q1[Q1[i ]^key[17]]^key[ 9]]^key[ 1]] ^
+ MDS2[Q1[Q0[Q0[i ]^key[18]]^key[10]]^key[ 2]] ^
+ MDS3[Q1[Q1[Q0[i ]^key[19]]^key[11]]^key[ 3]];
+ u32bit Y = MDS0[Q0[Q0[Q1[i+1]^key[20]]^key[12]]^key[ 4]] ^
+ MDS1[Q0[Q1[Q1[i+1]^key[21]]^key[13]]^key[ 5]] ^
+ MDS2[Q1[Q0[Q0[i+1]^key[22]]^key[14]]^key[ 6]] ^
+ MDS3[Q1[Q1[Q0[i+1]^key[23]]^key[15]]^key[ 7]];
+ Y = rotate_left(Y, 8);
+ X += Y; Y += X;
+
+ RK[i] = X;
+ RK[i+1] = rotate_left(Y, 9);
+ }
+ }
+ else if(length == 32)
+ {
+ for(size_t i = 0; i != 256; ++i)
+ {
+ SB[ i] = MDS0[Q0[Q0[Q1[Q1[i]^S[ 0]]^S[ 4]]^S[ 8]]^S[12]];
+ SB[256+i] = MDS1[Q0[Q1[Q1[Q0[i]^S[ 1]]^S[ 5]]^S[ 9]]^S[13]];
+ SB[512+i] = MDS2[Q1[Q0[Q0[Q0[i]^S[ 2]]^S[ 6]]^S[10]]^S[14]];
+ SB[768+i] = MDS3[Q1[Q1[Q0[Q1[i]^S[ 3]]^S[ 7]]^S[11]]^S[15]];
+ }
+
+ for(size_t i = 0; i != 40; i += 2)
+ {
+ u32bit X = MDS0[Q0[Q0[Q1[Q1[i ]^key[24]]^key[16]]^key[ 8]]^key[ 0]] ^
+ MDS1[Q0[Q1[Q1[Q0[i ]^key[25]]^key[17]]^key[ 9]]^key[ 1]] ^
+ MDS2[Q1[Q0[Q0[Q0[i ]^key[26]]^key[18]]^key[10]]^key[ 2]] ^
+ MDS3[Q1[Q1[Q0[Q1[i ]^key[27]]^key[19]]^key[11]]^key[ 3]];
+ u32bit Y = MDS0[Q0[Q0[Q1[Q1[i+1]^key[28]]^key[20]]^key[12]]^key[ 4]] ^
+ MDS1[Q0[Q1[Q1[Q0[i+1]^key[29]]^key[21]]^key[13]]^key[ 5]] ^
+ MDS2[Q1[Q0[Q0[Q0[i+1]^key[30]]^key[22]]^key[14]]^key[ 6]] ^
+ MDS3[Q1[Q1[Q0[Q1[i+1]^key[31]]^key[23]]^key[15]]^key[ 7]];
+ Y = rotate_left(Y, 8);
+ X += Y; Y += X;
+
+ RK[i] = X;
+ RK[i+1] = rotate_left(Y, 9);
+ }
+ }
+ }
+
+/*
+* Do one column of the RS matrix multiplcation
+*/
+void Twofish::rs_mul(byte S[4], byte key, size_t offset)
+ {
+ if(key)
+ {
+ byte X = POLY_TO_EXP[key - 1];
+
+ byte RS1 = RS[(4*offset ) % 32];
+ byte RS2 = RS[(4*offset+1) % 32];
+ byte RS3 = RS[(4*offset+2) % 32];
+ byte RS4 = RS[(4*offset+3) % 32];
+
+ S[0] ^= EXP_TO_POLY[(X + POLY_TO_EXP[RS1 - 1]) % 255];
+ S[1] ^= EXP_TO_POLY[(X + POLY_TO_EXP[RS2 - 1]) % 255];
+ S[2] ^= EXP_TO_POLY[(X + POLY_TO_EXP[RS3 - 1]) % 255];
+ S[3] ^= EXP_TO_POLY[(X + POLY_TO_EXP[RS4 - 1]) % 255];
+ }
+ }
+
+/*
+* Clear memory of sensitive data
+*/
+void Twofish::clear()
+ {
+ zap(SB);
+ zap(RK);
+ }
+
+}