/* Copyright (c) 2000, 2014, Oracle and/or its affiliates. All rights reserved. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; see the file COPYING. If not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. */ #include "runtime.hpp" #include "rabbit.hpp" namespace TaoCrypt { #define U32V(x) (word32)(x) #ifdef BIG_ENDIAN_ORDER #define LITTLE32(x) ByteReverse((word32)x) #else #define LITTLE32(x) (x) #endif // local namespace { /* Square a 32-bit unsigned integer to obtain the 64-bit result and return */ /* the upper 32 bits XOR the lower 32 bits */ word32 RABBIT_g_func(word32 x) { /* Temporary variables */ word32 a, b, h, l; /* Construct high and low argument for squaring */ a = x&0xFFFF; b = x>>16; /* Calculate high and low result of squaring */ h = (((U32V(a*a)>>17) + U32V(a*b))>>15) + b*b; l = x*x; /* Return high XOR low */ return U32V(h^l); } } // namespace local /* Calculate the next internal state */ void Rabbit::NextState(RabbitCtx which) { /* Temporary variables */ word32 g[8], c_old[8], i; Ctx* ctx; if (which == Master) ctx = &masterCtx_; else ctx = &workCtx_; /* Save old counter values */ for (i=0; i<8; i++) c_old[i] = ctx->c[i]; /* Calculate new counter values */ ctx->c[0] = U32V(ctx->c[0] + 0x4D34D34D + ctx->carry); ctx->c[1] = U32V(ctx->c[1] + 0xD34D34D3 + (ctx->c[0] < c_old[0])); ctx->c[2] = U32V(ctx->c[2] + 0x34D34D34 + (ctx->c[1] < c_old[1])); ctx->c[3] = U32V(ctx->c[3] + 0x4D34D34D + (ctx->c[2] < c_old[2])); ctx->c[4] = U32V(ctx->c[4] + 0xD34D34D3 + (ctx->c[3] < c_old[3])); ctx->c[5] = U32V(ctx->c[5] + 0x34D34D34 + (ctx->c[4] < c_old[4])); ctx->c[6] = U32V(ctx->c[6] + 0x4D34D34D + (ctx->c[5] < c_old[5])); ctx->c[7] = U32V(ctx->c[7] + 0xD34D34D3 + (ctx->c[6] < c_old[6])); ctx->carry = (ctx->c[7] < c_old[7]); /* Calculate the g-values */ for (i=0;i<8;i++) g[i] = RABBIT_g_func(U32V(ctx->x[i] + ctx->c[i])); /* Calculate new state values */ ctx->x[0] = U32V(g[0] + rotlFixed(g[7],16) + rotlFixed(g[6], 16)); ctx->x[1] = U32V(g[1] + rotlFixed(g[0], 8) + g[7]); ctx->x[2] = U32V(g[2] + rotlFixed(g[1],16) + rotlFixed(g[0], 16)); ctx->x[3] = U32V(g[3] + rotlFixed(g[2], 8) + g[1]); ctx->x[4] = U32V(g[4] + rotlFixed(g[3],16) + rotlFixed(g[2], 16)); ctx->x[5] = U32V(g[5] + rotlFixed(g[4], 8) + g[3]); ctx->x[6] = U32V(g[6] + rotlFixed(g[5],16) + rotlFixed(g[4], 16)); ctx->x[7] = U32V(g[7] + rotlFixed(g[6], 8) + g[5]); } /* IV setup */ void Rabbit::SetIV(const byte* iv) { /* Temporary variables */ word32 i0, i1, i2, i3, i; /* Generate four subvectors */ i0 = LITTLE32(*(word32*)(iv+0)); i2 = LITTLE32(*(word32*)(iv+4)); i1 = (i0>>16) | (i2&0xFFFF0000); i3 = (i2<<16) | (i0&0x0000FFFF); /* Modify counter values */ workCtx_.c[0] = masterCtx_.c[0] ^ i0; workCtx_.c[1] = masterCtx_.c[1] ^ i1; workCtx_.c[2] = masterCtx_.c[2] ^ i2; workCtx_.c[3] = masterCtx_.c[3] ^ i3; workCtx_.c[4] = masterCtx_.c[4] ^ i0; workCtx_.c[5] = masterCtx_.c[5] ^ i1; workCtx_.c[6] = masterCtx_.c[6] ^ i2; workCtx_.c[7] = masterCtx_.c[7] ^ i3; /* Copy state variables */ for (i=0; i<8; i++) workCtx_.x[i] = masterCtx_.x[i]; workCtx_.carry = masterCtx_.carry; /* Iterate the system four times */ for (i=0; i<4; i++) NextState(Work); } /* Key setup */ void Rabbit::SetKey(const byte* key, const byte* iv) { /* Temporary variables */ word32 k0, k1, k2, k3, i; /* Generate four subkeys */ k0 = LITTLE32(*(word32*)(key+ 0)); k1 = LITTLE32(*(word32*)(key+ 4)); k2 = LITTLE32(*(word32*)(key+ 8)); k3 = LITTLE32(*(word32*)(key+12)); /* Generate initial state variables */ masterCtx_.x[0] = k0; masterCtx_.x[2] = k1; masterCtx_.x[4] = k2; masterCtx_.x[6] = k3; masterCtx_.x[1] = U32V(k3<<16) | (k2>>16); masterCtx_.x[3] = U32V(k0<<16) | (k3>>16); masterCtx_.x[5] = U32V(k1<<16) | (k0>>16); masterCtx_.x[7] = U32V(k2<<16) | (k1>>16); /* Generate initial counter values */ masterCtx_.c[0] = rotlFixed(k2, 16); masterCtx_.c[2] = rotlFixed(k3, 16); masterCtx_.c[4] = rotlFixed(k0, 16); masterCtx_.c[6] = rotlFixed(k1, 16); masterCtx_.c[1] = (k0&0xFFFF0000) | (k1&0xFFFF); masterCtx_.c[3] = (k1&0xFFFF0000) | (k2&0xFFFF); masterCtx_.c[5] = (k2&0xFFFF0000) | (k3&0xFFFF); masterCtx_.c[7] = (k3&0xFFFF0000) | (k0&0xFFFF); /* Clear carry bit */ masterCtx_.carry = 0; /* Iterate the system four times */ for (i=0; i<4; i++) NextState(Master); /* Modify the counters */ for (i=0; i<8; i++) masterCtx_.c[i] ^= masterCtx_.x[(i+4)&0x7]; /* Copy master instance to work instance */ for (i=0; i<8; i++) { workCtx_.x[i] = masterCtx_.x[i]; workCtx_.c[i] = masterCtx_.c[i]; } workCtx_.carry = masterCtx_.carry; if (iv) SetIV(iv); } /* Encrypt/decrypt a message of any size */ void Rabbit::Process(byte* output, const byte* input, word32 msglen) { /* Temporary variables */ word32 i; /* Encrypt/decrypt all full blocks */ while (msglen >= 16) { /* Iterate the system */ NextState(Work); /* Encrypt/decrypt 16 bytes of data */ *(word32*)(output+ 0) = *(word32*)(input+ 0) ^ LITTLE32(workCtx_.x[0] ^ (workCtx_.x[5]>>16) ^ U32V(workCtx_.x[3]<<16)); *(word32*)(output+ 4) = *(word32*)(input+ 4) ^ LITTLE32(workCtx_.x[2] ^ (workCtx_.x[7]>>16) ^ U32V(workCtx_.x[5]<<16)); *(word32*)(output+ 8) = *(word32*)(input+ 8) ^ LITTLE32(workCtx_.x[4] ^ (workCtx_.x[1]>>16) ^ U32V(workCtx_.x[7]<<16)); *(word32*)(output+12) = *(word32*)(input+12) ^ LITTLE32(workCtx_.x[6] ^ (workCtx_.x[3]>>16) ^ U32V(workCtx_.x[1]<<16)); /* Increment pointers and decrement length */ input += 16; output += 16; msglen -= 16; } /* Encrypt/decrypt remaining data */ if (msglen) { word32 tmp[4]; byte* buffer = (byte*)tmp; memset(tmp, 0, sizeof(tmp)); /* help static analysis */ /* Iterate the system */ NextState(Work); /* Generate 16 bytes of pseudo-random data */ tmp[0] = LITTLE32(workCtx_.x[0] ^ (workCtx_.x[5]>>16) ^ U32V(workCtx_.x[3]<<16)); tmp[1] = LITTLE32(workCtx_.x[2] ^ (workCtx_.x[7]>>16) ^ U32V(workCtx_.x[5]<<16)); tmp[2] = LITTLE32(workCtx_.x[4] ^ (workCtx_.x[1]>>16) ^ U32V(workCtx_.x[7]<<16)); tmp[3] = LITTLE32(workCtx_.x[6] ^ (workCtx_.x[3]>>16) ^ U32V(workCtx_.x[1]<<16)); /* Encrypt/decrypt the data */ for (i=0; i