From f51841ba5237952dda3e76df643d3ae13bed3df5 Mon Sep 17 00:00:00 2001 From: lloyd Date: Tue, 11 Aug 2009 02:31:17 +0000 Subject: Change the BlockCipher interface to support multi-block encryption and decryption. Currently only used for counter mode. Doesn't offer much advantage as-is (though might help slightly, in terms of cache effects), but allows for SIMD implementations to process multiple blocks in parallel when possible. Particularly thinking here of Serpent; TEA/XTEA also seem promising in this sense, as is Threefish once that is implemented as a standalone block cipher. --- src/block/safer/safer_sk.cpp | 97 +++++++++++++++++++++++++++----------------- 1 file changed, 59 insertions(+), 38 deletions(-) (limited to 'src/block/safer/safer_sk.cpp') diff --git a/src/block/safer/safer_sk.cpp b/src/block/safer/safer_sk.cpp index f72c4773b..eb5c22fc9 100644 --- a/src/block/safer/safer_sk.cpp +++ b/src/block/safer/safer_sk.cpp @@ -1,6 +1,6 @@ /* * SAFER-SK -* (C) 1999-2007 Jack Lloyd +* (C) 1999-2009 Jack Lloyd * * Distributed under the terms of the Botan license */ @@ -15,54 +15,75 @@ namespace Botan { /* * SAFER-SK Encryption */ -void SAFER_SK::enc(const byte in[], byte out[]) const +void SAFER_SK::encrypt_n(const byte in[], byte out[], u32bit blocks) const { - byte A = in[0], B = in[1], C = in[2], D = in[3], - E = in[4], F = in[5], G = in[6], H = in[7], X, Y; - for(u32bit j = 0; j != 16*ROUNDS; j += 16) + for(u32bit i = 0; i != blocks; ++i) { - A = EXP[A ^ EK[j ]]; B = LOG[B + EK[j+1]]; - C = LOG[C + EK[j+2]]; D = EXP[D ^ EK[j+3]]; - E = EXP[E ^ EK[j+4]]; F = LOG[F + EK[j+5]]; - G = LOG[G + EK[j+6]]; H = EXP[H ^ EK[j+7]]; - A += EK[j+ 8]; B ^= EK[j+ 9]; C ^= EK[j+10]; D += EK[j+11]; - E += EK[j+12]; F ^= EK[j+13]; G ^= EK[j+14]; H += EK[j+15]; - B += A; D += C; F += E; H += G; A += B; C += D; E += F; G += H; - C += A; G += E; D += B; H += F; A += C; E += G; B += D; F += H; - H += D; Y = D + H; D = B + F; X = B + D; B = A + E; - A += B; F = C + G; E = C + F; C = X; G = Y; + byte A = in[0], B = in[1], C = in[2], D = in[3], + E = in[4], F = in[5], G = in[6], H = in[7], X, Y; + + for(u32bit j = 0; j != 16*ROUNDS; j += 16) + { + A = EXP[A ^ EK[j ]]; B = LOG[B + EK[j+1]]; + C = LOG[C + EK[j+2]]; D = EXP[D ^ EK[j+3]]; + E = EXP[E ^ EK[j+4]]; F = LOG[F + EK[j+5]]; + G = LOG[G + EK[j+6]]; H = EXP[H ^ EK[j+7]]; + + A += EK[j+ 8]; B ^= EK[j+ 9]; C ^= EK[j+10]; D += EK[j+11]; + E += EK[j+12]; F ^= EK[j+13]; G ^= EK[j+14]; H += EK[j+15]; + + B += A; D += C; F += E; H += G; A += B; C += D; E += F; G += H; + C += A; G += E; D += B; H += F; A += C; E += G; B += D; F += H; + H += D; Y = D + H; D = B + F; X = B + D; B = A + E; + A += B; F = C + G; E = C + F; C = X; G = Y; + } + + out[0] = A ^ EK[16*ROUNDS+0]; out[1] = B + EK[16*ROUNDS+1]; + out[2] = C + EK[16*ROUNDS+2]; out[3] = D ^ EK[16*ROUNDS+3]; + out[4] = E ^ EK[16*ROUNDS+4]; out[5] = F + EK[16*ROUNDS+5]; + out[6] = G + EK[16*ROUNDS+6]; out[7] = H ^ EK[16*ROUNDS+7]; + + in += BLOCK_SIZE; + out += BLOCK_SIZE; } - out[0] = A ^ EK[16*ROUNDS+0]; out[1] = B + EK[16*ROUNDS+1]; - out[2] = C + EK[16*ROUNDS+2]; out[3] = D ^ EK[16*ROUNDS+3]; - out[4] = E ^ EK[16*ROUNDS+4]; out[5] = F + EK[16*ROUNDS+5]; - out[6] = G + EK[16*ROUNDS+6]; out[7] = H ^ EK[16*ROUNDS+7]; } /* * SAFER-SK Decryption */ -void SAFER_SK::dec(const byte in[], byte out[]) const +void SAFER_SK::decrypt_n(const byte in[], byte out[], u32bit blocks) const { - byte A = in[0], B = in[1], C = in[2], D = in[3], - E = in[4], F = in[5], G = in[6], H = in[7]; - A ^= EK[16*ROUNDS+0]; B -= EK[16*ROUNDS+1]; C -= EK[16*ROUNDS+2]; - D ^= EK[16*ROUNDS+3]; E ^= EK[16*ROUNDS+4]; F -= EK[16*ROUNDS+5]; - G -= EK[16*ROUNDS+6]; H ^= EK[16*ROUNDS+7]; - for(s32bit j = 16*(ROUNDS-1); j >= 0; j -= 16) + for(u32bit i = 0; i != blocks; ++i) { - byte T = E; E = B; B = C; C = T; T = F; F = D; D = G; G = T; - A -= E; B -= F; C -= G; D -= H; E -= A; F -= B; G -= C; H -= D; - A -= C; E -= G; B -= D; F -= H; C -= A; G -= E; D -= B; H -= F; - A -= B; C -= D; E -= F; G -= H; B -= A; D -= C; F -= E; H -= G; - A = LOG[A - EK[j+8 ] + 256]; B = EXP[B ^ EK[j+9 ]]; - C = EXP[C ^ EK[j+10]]; D = LOG[D - EK[j+11] + 256]; - E = LOG[E - EK[j+12] + 256]; F = EXP[F ^ EK[j+13]]; - G = EXP[G ^ EK[j+14]]; H = LOG[H - EK[j+15] + 256]; - A ^= EK[j+0]; B -= EK[j+1]; C -= EK[j+2]; D ^= EK[j+3]; - E ^= EK[j+4]; F -= EK[j+5]; G -= EK[j+6]; H ^= EK[j+7]; + byte A = in[0], B = in[1], C = in[2], D = in[3], + E = in[4], F = in[5], G = in[6], H = in[7]; + + A ^= EK[16*ROUNDS+0]; B -= EK[16*ROUNDS+1]; C -= EK[16*ROUNDS+2]; + D ^= EK[16*ROUNDS+3]; E ^= EK[16*ROUNDS+4]; F -= EK[16*ROUNDS+5]; + G -= EK[16*ROUNDS+6]; H ^= EK[16*ROUNDS+7]; + + for(s32bit j = 16*(ROUNDS-1); j >= 0; j -= 16) + { + byte T = E; E = B; B = C; C = T; T = F; F = D; D = G; G = T; + A -= E; B -= F; C -= G; D -= H; E -= A; F -= B; G -= C; H -= D; + A -= C; E -= G; B -= D; F -= H; C -= A; G -= E; D -= B; H -= F; + A -= B; C -= D; E -= F; G -= H; B -= A; D -= C; F -= E; H -= G; + + A = LOG[A - EK[j+8 ] + 256]; B = EXP[B ^ EK[j+9 ]]; + C = EXP[C ^ EK[j+10]]; D = LOG[D - EK[j+11] + 256]; + E = LOG[E - EK[j+12] + 256]; F = EXP[F ^ EK[j+13]]; + G = EXP[G ^ EK[j+14]]; H = LOG[H - EK[j+15] + 256]; + + A ^= EK[j+0]; B -= EK[j+1]; C -= EK[j+2]; D ^= EK[j+3]; + E ^= EK[j+4]; F -= EK[j+5]; G -= EK[j+6]; H ^= EK[j+7]; + } + + out[0] = A; out[1] = B; out[2] = C; out[3] = D; + out[4] = E; out[5] = F; out[6] = G; out[7] = H; + + in += BLOCK_SIZE; + out += BLOCK_SIZE; } - out[0] = A; out[1] = B; out[2] = C; out[3] = D; - out[4] = E; out[5] = F; out[6] = G; out[7] = H; } /* -- cgit v1.2.3