hc128.c

00001 /* hc128.c
00002  *
00003  * Copyright (C) 2006-2012 Sawtooth Consulting Ltd.
00004  *
00005  * This file is part of CyaSSL.
00006  *
00007  * CyaSSL is free software; you can redistribute it and/or modify
00008  * it under the terms of the GNU General Public License as published by
00009  * the Free Software Foundation; either version 2 of the License, or
00010  * (at your option) any later version.
00011  *
00012  * CyaSSL is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00015  * GNU General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU General Public License
00018  * along with this program; if not, write to the Free Software
00019  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
00020  */
00021 
00022 #ifdef HAVE_CONFIG_H
00023     #include <config.h>
00024 #endif
00025 
00026 #ifdef HAVE_HC128
00027 
00028 #include <cyassl/ctaocrypt/hc128.h>
00029 #ifdef NO_INLINE
00030     #include <cyassl/ctaocrypt/hc128.h>
00031 #else
00032     #include <ctaocrypt/src/misc.c>
00033 #endif
00034 
00035 
00036 #ifdef BIG_ENDIAN_ORDER
00037     #define LITTLE32(x) ByteReverseWord32(x)
00038 #else
00039     #define LITTLE32(x) (x)
00040 #endif
00041 
00042 
00043 /*h1 function*/
00044 #define h1(ctx, x, y) {                         \
00045      byte a,c;                                  \
00046      a = (byte) (x);                            \
00047      c = (byte) ((x) >> 16);                    \
00048      y = (ctx->T[512+a])+(ctx->T[512+256+c]);   \
00049 }
00050 
00051 /*h2 function*/
00052 #define h2(ctx, x, y) {                         \
00053      byte a,c;                                  \
00054      a = (byte) (x);                            \
00055      c = (byte) ((x) >> 16);                    \
00056      y = (ctx->T[a])+(ctx->T[256+c]);           \
00057 }
00058 
00059 /*one step of HC-128, update P and generate 32 bits keystream*/
00060 #define step_P(ctx,u,v,a,b,c,d,n){              \
00061      word32 tem0,tem1,tem2,tem3;                \
00062      h1((ctx),(ctx->X[(d)]),tem3);              \
00063      tem0 = rotrFixed((ctx->T[(v)]),23);        \
00064      tem1 = rotrFixed((ctx->X[(c)]),10);        \
00065      tem2 = rotrFixed((ctx->X[(b)]),8);         \
00066      (ctx->T[(u)]) += tem2+(tem0 ^ tem1);       \
00067      (ctx->X[(a)]) = (ctx->T[(u)]);             \
00068      (n) = tem3 ^ (ctx->T[(u)]) ;               \
00069 }       
00070 
00071 /*one step of HC-128, update Q and generate 32 bits keystream*/
00072 #define step_Q(ctx,u,v,a,b,c,d,n){              \
00073      word32 tem0,tem1,tem2,tem3;                \
00074      h2((ctx),(ctx->Y[(d)]),tem3);              \
00075      tem0 = rotrFixed((ctx->T[(v)]),(32-23));   \
00076      tem1 = rotrFixed((ctx->Y[(c)]),(32-10));   \
00077      tem2 = rotrFixed((ctx->Y[(b)]),(32-8));    \
00078      (ctx->T[(u)]) += tem2 + (tem0 ^ tem1);     \
00079      (ctx->Y[(a)]) = (ctx->T[(u)]);             \
00080      (n) = tem3 ^ (ctx->T[(u)]) ;               \
00081 }   
00082 
00083 /*16 steps of HC-128, generate 512 bits keystream*/
00084 static void generate_keystream(HC128* ctx, word32* keystream)  
00085 {
00086    word32 cc,dd;
00087    cc = ctx->counter1024 & 0x1ff;
00088    dd = (cc+16)&0x1ff;
00089 
00090    if (ctx->counter1024 < 512)    
00091    {           
00092       ctx->counter1024 = (ctx->counter1024 + 16) & 0x3ff;
00093       step_P(ctx, cc+0, cc+1, 0, 6, 13,4, keystream[0]);
00094       step_P(ctx, cc+1, cc+2, 1, 7, 14,5, keystream[1]);
00095       step_P(ctx, cc+2, cc+3, 2, 8, 15,6, keystream[2]);
00096       step_P(ctx, cc+3, cc+4, 3, 9, 0, 7, keystream[3]);
00097       step_P(ctx, cc+4, cc+5, 4, 10,1, 8, keystream[4]);
00098       step_P(ctx, cc+5, cc+6, 5, 11,2, 9, keystream[5]);
00099       step_P(ctx, cc+6, cc+7, 6, 12,3, 10,keystream[6]);
00100       step_P(ctx, cc+7, cc+8, 7, 13,4, 11,keystream[7]);
00101       step_P(ctx, cc+8, cc+9, 8, 14,5, 12,keystream[8]);
00102       step_P(ctx, cc+9, cc+10,9, 15,6, 13,keystream[9]);
00103       step_P(ctx, cc+10,cc+11,10,0, 7, 14,keystream[10]);
00104       step_P(ctx, cc+11,cc+12,11,1, 8, 15,keystream[11]);
00105       step_P(ctx, cc+12,cc+13,12,2, 9, 0, keystream[12]);
00106       step_P(ctx, cc+13,cc+14,13,3, 10,1, keystream[13]);
00107       step_P(ctx, cc+14,cc+15,14,4, 11,2, keystream[14]);
00108       step_P(ctx, cc+15,dd+0, 15,5, 12,3, keystream[15]);
00109    }
00110    else                    
00111    {
00112       ctx->counter1024 = (ctx->counter1024 + 16) & 0x3ff;
00113       step_Q(ctx, 512+cc+0, 512+cc+1, 0, 6, 13,4, keystream[0]);
00114       step_Q(ctx, 512+cc+1, 512+cc+2, 1, 7, 14,5, keystream[1]);
00115       step_Q(ctx, 512+cc+2, 512+cc+3, 2, 8, 15,6, keystream[2]);
00116       step_Q(ctx, 512+cc+3, 512+cc+4, 3, 9, 0, 7, keystream[3]);
00117       step_Q(ctx, 512+cc+4, 512+cc+5, 4, 10,1, 8, keystream[4]);
00118       step_Q(ctx, 512+cc+5, 512+cc+6, 5, 11,2, 9, keystream[5]);
00119       step_Q(ctx, 512+cc+6, 512+cc+7, 6, 12,3, 10,keystream[6]);
00120       step_Q(ctx, 512+cc+7, 512+cc+8, 7, 13,4, 11,keystream[7]);
00121       step_Q(ctx, 512+cc+8, 512+cc+9, 8, 14,5, 12,keystream[8]);
00122       step_Q(ctx, 512+cc+9, 512+cc+10,9, 15,6, 13,keystream[9]);
00123       step_Q(ctx, 512+cc+10,512+cc+11,10,0, 7, 14,keystream[10]);
00124       step_Q(ctx, 512+cc+11,512+cc+12,11,1, 8, 15,keystream[11]);
00125       step_Q(ctx, 512+cc+12,512+cc+13,12,2, 9, 0, keystream[12]);
00126       step_Q(ctx, 512+cc+13,512+cc+14,13,3, 10,1, keystream[13]);
00127       step_Q(ctx, 512+cc+14,512+cc+15,14,4, 11,2, keystream[14]);
00128       step_Q(ctx, 512+cc+15,512+dd+0, 15,5, 12,3, keystream[15]);
00129    }
00130 }
00131 
00132 
00133 /* The following defines the initialization functions */
00134 #define f1(x)  (rotrFixed((x),7)  ^ rotrFixed((x),18) ^ ((x) >> 3))
00135 #define f2(x)  (rotrFixed((x),17) ^ rotrFixed((x),19) ^ ((x) >> 10))
00136 
00137 /*update table P*/
00138 #define update_P(ctx,u,v,a,b,c,d){                  \
00139      word32 tem0,tem1,tem2,tem3;                    \
00140      tem0 = rotrFixed((ctx->T[(v)]),23);            \
00141      tem1 = rotrFixed((ctx->X[(c)]),10);            \
00142      tem2 = rotrFixed((ctx->X[(b)]),8);             \
00143      h1((ctx),(ctx->X[(d)]),tem3);                  \
00144      (ctx->T[(u)]) = ((ctx->T[(u)]) + tem2+(tem0^tem1)) ^ tem3;     \
00145      (ctx->X[(a)]) = (ctx->T[(u)]);                 \
00146 }  
00147 
00148 /*update table Q*/
00149 #define update_Q(ctx,u,v,a,b,c,d){                  \
00150      word32 tem0,tem1,tem2,tem3;                    \
00151      tem0 = rotrFixed((ctx->T[(v)]),(32-23));       \
00152      tem1 = rotrFixed((ctx->Y[(c)]),(32-10));       \
00153      tem2 = rotrFixed((ctx->Y[(b)]),(32-8));        \
00154      h2((ctx),(ctx->Y[(d)]),tem3);                  \
00155      (ctx->T[(u)]) = ((ctx->T[(u)]) + tem2+(tem0^tem1)) ^ tem3;     \
00156      (ctx->Y[(a)]) = (ctx->T[(u)]);                 \
00157 }     
00158 
00159 /*16 steps of HC-128, without generating keystream, */
00160 /*but use the outputs to update P and Q*/
00161 static void setup_update(HC128* ctx)  /*each time 16 steps*/
00162 {
00163    word32 cc,dd;
00164    cc = ctx->counter1024 & 0x1ff;
00165    dd = (cc+16)&0x1ff;
00166 
00167    if (ctx->counter1024 < 512)    
00168    {           
00169       ctx->counter1024 = (ctx->counter1024 + 16) & 0x3ff;
00170       update_P(ctx, cc+0, cc+1, 0, 6, 13, 4);
00171       update_P(ctx, cc+1, cc+2, 1, 7, 14, 5);
00172       update_P(ctx, cc+2, cc+3, 2, 8, 15, 6);
00173       update_P(ctx, cc+3, cc+4, 3, 9, 0,  7);
00174       update_P(ctx, cc+4, cc+5, 4, 10,1,  8);
00175       update_P(ctx, cc+5, cc+6, 5, 11,2,  9);
00176       update_P(ctx, cc+6, cc+7, 6, 12,3,  10);
00177       update_P(ctx, cc+7, cc+8, 7, 13,4,  11);
00178       update_P(ctx, cc+8, cc+9, 8, 14,5,  12);
00179       update_P(ctx, cc+9, cc+10,9, 15,6,  13);
00180       update_P(ctx, cc+10,cc+11,10,0, 7,  14);
00181       update_P(ctx, cc+11,cc+12,11,1, 8,  15);
00182       update_P(ctx, cc+12,cc+13,12,2, 9,  0);
00183       update_P(ctx, cc+13,cc+14,13,3, 10, 1);
00184       update_P(ctx, cc+14,cc+15,14,4, 11, 2);
00185       update_P(ctx, cc+15,dd+0, 15,5, 12, 3);   
00186    }
00187    else                    
00188    {
00189       ctx->counter1024 = (ctx->counter1024 + 16) & 0x3ff;
00190       update_Q(ctx, 512+cc+0, 512+cc+1, 0, 6, 13, 4);
00191       update_Q(ctx, 512+cc+1, 512+cc+2, 1, 7, 14, 5);
00192       update_Q(ctx, 512+cc+2, 512+cc+3, 2, 8, 15, 6);
00193       update_Q(ctx, 512+cc+3, 512+cc+4, 3, 9, 0,  7);
00194       update_Q(ctx, 512+cc+4, 512+cc+5, 4, 10,1,  8);
00195       update_Q(ctx, 512+cc+5, 512+cc+6, 5, 11,2,  9);
00196       update_Q(ctx, 512+cc+6, 512+cc+7, 6, 12,3,  10);
00197       update_Q(ctx, 512+cc+7, 512+cc+8, 7, 13,4,  11);
00198       update_Q(ctx, 512+cc+8, 512+cc+9, 8, 14,5,  12);
00199       update_Q(ctx, 512+cc+9, 512+cc+10,9, 15,6,  13);
00200       update_Q(ctx, 512+cc+10,512+cc+11,10,0, 7,  14);
00201       update_Q(ctx, 512+cc+11,512+cc+12,11,1, 8,  15);
00202       update_Q(ctx, 512+cc+12,512+cc+13,12,2, 9,  0);
00203       update_Q(ctx, 512+cc+13,512+cc+14,13,3, 10, 1);
00204       update_Q(ctx, 512+cc+14,512+cc+15,14,4, 11, 2);
00205       update_Q(ctx, 512+cc+15,512+dd+0, 15,5, 12, 3); 
00206    }       
00207 }
00208 
00209 
00210 /* for the 128-bit key:  key[0]...key[15]
00211 *  key[0] is the least significant byte of ctx->key[0] (K_0);
00212 *  key[3] is the most significant byte of ctx->key[0]  (K_0);
00213 *  ...
00214 *  key[12] is the least significant byte of ctx->key[3] (K_3)
00215 *  key[15] is the most significant byte of ctx->key[3]  (K_3)
00216 *
00217 *  for the 128-bit iv:  iv[0]...iv[15]
00218 *  iv[0] is the least significant byte of ctx->iv[0] (IV_0);
00219 *  iv[3] is the most significant byte of ctx->iv[0]  (IV_0);
00220 *  ...
00221 *  iv[12] is the least significant byte of ctx->iv[3] (IV_3)
00222 *  iv[15] is the most significant byte of ctx->iv[3]  (IV_3)
00223 */
00224 
00225 
00226 
00227 static void Hc128_SetIV(HC128* ctx, const byte* iv)
00228 { 
00229     word32 i;
00230     
00231     for (i = 0; i < (128 >> 5); i++)
00232         ctx->iv[i] = LITTLE32(((word32*)iv)[i]);
00233     
00234     for (; i < 8; i++) ctx->iv[i] = ctx->iv[i-4];
00235   
00236     /* expand the key and IV into the table T */ 
00237     /* (expand the key and IV into the table P and Q) */ 
00238     
00239     for (i = 0; i < 8;  i++)   ctx->T[i] = ctx->key[i];
00240     for (i = 8; i < 16; i++)   ctx->T[i] = ctx->iv[i-8];
00241 
00242     for (i = 16; i < (256+16); i++) 
00243         ctx->T[i] = f2(ctx->T[i-2]) + ctx->T[i-7] + f1(ctx->T[i-15]) +
00244                                                        ctx->T[i-16]+i;
00245     
00246     for (i = 0; i < 16;  i++)  ctx->T[i] = ctx->T[256+i];
00247 
00248     for (i = 16; i < 1024; i++) 
00249         ctx->T[i] = f2(ctx->T[i-2]) + ctx->T[i-7] + f1(ctx->T[i-15]) +
00250                                                        ctx->T[i-16]+256+i;
00251     
00252     /* initialize counter1024, X and Y */
00253     ctx->counter1024 = 0;
00254     for (i = 0; i < 16; i++) ctx->X[i] = ctx->T[512-16+i];
00255     for (i = 0; i < 16; i++) ctx->Y[i] = ctx->T[512+512-16+i];
00256     
00257     /* run the cipher 1024 steps before generating the output */
00258     for (i = 0; i < 64; i++)  setup_update(ctx);  
00259 }
00260 
00261 
00262 void Hc128_SetKey(HC128* ctx, const byte* key, const byte* iv)
00263 { 
00264   word32 i;  
00265 
00266   /* Key size in bits 128 */ 
00267   for (i = 0; i < (128 >> 5); i++)
00268       ctx->key[i] = LITTLE32(((word32*)key)[i]);
00269  
00270   for ( ; i < 8 ; i++) ctx->key[i] = ctx->key[i-4];
00271 
00272   Hc128_SetIV(ctx, iv);
00273 }
00274 
00275 
00276 /* The following defines the encryption of data stream */
00277 void Hc128_Process(HC128* ctx, byte* output, const byte* input, word32 msglen)
00278 {
00279   word32 i, keystream[16];
00280 
00281   for ( ; msglen >= 64; msglen -= 64, input += 64, output += 64)
00282   {
00283       generate_keystream(ctx, keystream);
00284 
00285       /* unroll loop */
00286       ((word32*)output)[0]  = ((word32*)input)[0]  ^ LITTLE32(keystream[0]);
00287       ((word32*)output)[1]  = ((word32*)input)[1]  ^ LITTLE32(keystream[1]);
00288       ((word32*)output)[2]  = ((word32*)input)[2]  ^ LITTLE32(keystream[2]);
00289       ((word32*)output)[3]  = ((word32*)input)[3]  ^ LITTLE32(keystream[3]);
00290       ((word32*)output)[4]  = ((word32*)input)[4]  ^ LITTLE32(keystream[4]);
00291       ((word32*)output)[5]  = ((word32*)input)[5]  ^ LITTLE32(keystream[5]);
00292       ((word32*)output)[6]  = ((word32*)input)[6]  ^ LITTLE32(keystream[6]);
00293       ((word32*)output)[7]  = ((word32*)input)[7]  ^ LITTLE32(keystream[7]);
00294       ((word32*)output)[8]  = ((word32*)input)[8]  ^ LITTLE32(keystream[8]);
00295       ((word32*)output)[9]  = ((word32*)input)[9]  ^ LITTLE32(keystream[9]);
00296       ((word32*)output)[10] = ((word32*)input)[10] ^ LITTLE32(keystream[10]);
00297       ((word32*)output)[11] = ((word32*)input)[11] ^ LITTLE32(keystream[11]);
00298       ((word32*)output)[12] = ((word32*)input)[12] ^ LITTLE32(keystream[12]);
00299       ((word32*)output)[13] = ((word32*)input)[13] ^ LITTLE32(keystream[13]);
00300       ((word32*)output)[14] = ((word32*)input)[14] ^ LITTLE32(keystream[14]);
00301       ((word32*)output)[15] = ((word32*)input)[15] ^ LITTLE32(keystream[15]);
00302   }
00303 
00304   if (msglen > 0)
00305   {
00306       generate_keystream(ctx, keystream);
00307 
00308 #ifdef BIG_ENDIAN_ORDER
00309       {
00310           word32 wordsLeft = msglen / sizeof(word32);
00311           if (msglen % sizeof(word32)) wordsLeft++;
00312           
00313           ByteReverseWords(keystream, keystream, wordsLeft * sizeof(word32));
00314       }
00315 #endif
00316 
00317       for (i = 0; i < msglen; i++)
00318           output[i] = input[i] ^ ((byte*)keystream)[i];
00319   }
00320 
00321 }
00322 
00323 
00324 #else  /* HAVE_HC128 */
00325 
00326 
00327 #ifdef _MSC_VER
00328     /* 4206 warning for blank file */
00329     #pragma warning(disable: 4206)
00330 #endif
00331 
00332 
00333 #endif /* HAVE_HC128 */