Todd Ouska
CyaSSL is an SSL library for devices like mbed.
Dependents: cyassl-client Sync
Diff: rabbit.c
- Revision:
- 0:5045d2638c29
diff -r 000000000000 -r 5045d2638c29 rabbit.c
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/rabbit.c Sat Feb 05 01:09:17 2011 +0000
@@ -0,0 +1,239 @@
+/* rabbit.c
+ *
+ * Copyright (C) 2006-2009 Sawtooth Consulting Ltd.
+ *
+ * This file is part of CyaSSL.
+ *
+ * CyaSSL 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * CyaSSL 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; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
+ */
+
+
+#ifndef NO_RABBIT
+
+#include "rabbit.h"
+#include "misc.c"
+
+
+#ifdef BIG_ENDIAN_ORDER
+ #define LITTLE32(x) ByteReverseWord32(x)
+#else
+ #define LITTLE32(x) (x)
+#endif
+
+#define U32V(x) (word32)(x)
+
+
+/* Square a 32-bit unsigned integer to obtain the 64-bit result and return */
+/* the upper 32 bits XOR the lower 32 bits */
+static 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);
+}
+
+
+/* Calculate the next internal state */
+static void RABBIT_next_state(RabbitCtx* ctx)
+{
+ /* Temporary variables */
+ word32 g[8], c_old[8], i;
+
+ /* 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 */
+static void RabbitSetIV(Rabbit* ctx, 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 */
+ ctx->workCtx.c[0] = ctx->masterCtx.c[0] ^ i0;
+ ctx->workCtx.c[1] = ctx->masterCtx.c[1] ^ i1;
+ ctx->workCtx.c[2] = ctx->masterCtx.c[2] ^ i2;
+ ctx->workCtx.c[3] = ctx->masterCtx.c[3] ^ i3;
+ ctx->workCtx.c[4] = ctx->masterCtx.c[4] ^ i0;
+ ctx->workCtx.c[5] = ctx->masterCtx.c[5] ^ i1;
+ ctx->workCtx.c[6] = ctx->masterCtx.c[6] ^ i2;
+ ctx->workCtx.c[7] = ctx->masterCtx.c[7] ^ i3;
+
+ /* Copy state variables */
+ for (i=0; i<8; i++)
+ ctx->workCtx.x[i] = ctx->masterCtx.x[i];
+ ctx->workCtx.carry = ctx->masterCtx.carry;
+
+ /* Iterate the system four times */
+ for (i=0; i<4; i++)
+ RABBIT_next_state(&(ctx->workCtx));
+}
+
+
+/* Key setup */
+void RabbitSetKey(Rabbit* ctx, 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 */
+ ctx->masterCtx.x[0] = k0;
+ ctx->masterCtx.x[2] = k1;
+ ctx->masterCtx.x[4] = k2;
+ ctx->masterCtx.x[6] = k3;
+ ctx->masterCtx.x[1] = U32V(k3<<16) | (k2>>16);
+ ctx->masterCtx.x[3] = U32V(k0<<16) | (k3>>16);
+ ctx->masterCtx.x[5] = U32V(k1<<16) | (k0>>16);
+ ctx->masterCtx.x[7] = U32V(k2<<16) | (k1>>16);
+
+ /* Generate initial counter values */
+ ctx->masterCtx.c[0] = rotlFixed(k2, 16);
+ ctx->masterCtx.c[2] = rotlFixed(k3, 16);
+ ctx->masterCtx.c[4] = rotlFixed(k0, 16);
+ ctx->masterCtx.c[6] = rotlFixed(k1, 16);
+ ctx->masterCtx.c[1] = (k0&0xFFFF0000) | (k1&0xFFFF);
+ ctx->masterCtx.c[3] = (k1&0xFFFF0000) | (k2&0xFFFF);
+ ctx->masterCtx.c[5] = (k2&0xFFFF0000) | (k3&0xFFFF);
+ ctx->masterCtx.c[7] = (k3&0xFFFF0000) | (k0&0xFFFF);
+
+ /* Clear carry bit */
+ ctx->masterCtx.carry = 0;
+
+ /* Iterate the system four times */
+ for (i=0; i<4; i++)
+ RABBIT_next_state(&(ctx->masterCtx));
+
+ /* Modify the counters */
+ for (i=0; i<8; i++)
+ ctx->masterCtx.c[i] ^= ctx->masterCtx.x[(i+4)&0x7];
+
+ /* Copy master instance to work instance */
+ for (i=0; i<8; i++) {
+ ctx->workCtx.x[i] = ctx->masterCtx.x[i];
+ ctx->workCtx.c[i] = ctx->masterCtx.c[i];
+ }
+ ctx->workCtx.carry = ctx->masterCtx.carry;
+
+ if (iv) RabbitSetIV(ctx, iv);
+}
+
+
+/* Encrypt/decrypt a message of any size */
+void RabbitProcess(Rabbit* ctx, byte* output, const byte* input, word32 msglen)
+{
+
+ /* Encrypt/decrypt all full blocks */
+ while (msglen >= 16) {
+ /* Iterate the system */
+ RABBIT_next_state(&(ctx->workCtx));
+
+ /* Encrypt/decrypt 16 bytes of data */
+ *(word32*)(output+ 0) = *(word32*)(input+ 0) ^
+ LITTLE32(ctx->workCtx.x[0] ^ (ctx->workCtx.x[5]>>16) ^
+ U32V(ctx->workCtx.x[3]<<16));
+ *(word32*)(output+ 4) = *(word32*)(input+ 4) ^
+ LITTLE32(ctx->workCtx.x[2] ^ (ctx->workCtx.x[7]>>16) ^
+ U32V(ctx->workCtx.x[5]<<16));
+ *(word32*)(output+ 8) = *(word32*)(input+ 8) ^
+ LITTLE32(ctx->workCtx.x[4] ^ (ctx->workCtx.x[1]>>16) ^
+ U32V(ctx->workCtx.x[7]<<16));
+ *(word32*)(output+12) = *(word32*)(input+12) ^
+ LITTLE32(ctx->workCtx.x[6] ^ (ctx->workCtx.x[3]>>16) ^
+ U32V(ctx->workCtx.x[1]<<16));
+
+ /* Increment pointers and decrement length */
+ input += 16;
+ output += 16;
+ msglen -= 16;
+ }
+
+ /* Encrypt/decrypt remaining data */
+ if (msglen) {
+
+ word32 i;
+ word32 tmp[4];
+ byte* buffer = (byte*)tmp;
+
+ /* Iterate the system */
+ RABBIT_next_state(&(ctx->workCtx));
+
+ /* Generate 16 bytes of pseudo-random data */
+ tmp[0] = LITTLE32(ctx->workCtx.x[0] ^
+ (ctx->workCtx.x[5]>>16) ^ U32V(ctx->workCtx.x[3]<<16));
+ tmp[1] = LITTLE32(ctx->workCtx.x[2] ^
+ (ctx->workCtx.x[7]>>16) ^ U32V(ctx->workCtx.x[5]<<16));
+ tmp[2] = LITTLE32(ctx->workCtx.x[4] ^
+ (ctx->workCtx.x[1]>>16) ^ U32V(ctx->workCtx.x[7]<<16));
+ tmp[3] = LITTLE32(ctx->workCtx.x[6] ^
+ (ctx->workCtx.x[3]>>16) ^ U32V(ctx->workCtx.x[1]<<16));
+
+ /* Encrypt/decrypt the data */
+ for (i=0; i<msglen; i++)
+ output[i] = input[i] ^ buffer[i];
+ }
+}
+
+
+
+#endif /* NO_RABBIT */