sha.c

00001 /* sha.c
00002  *
00003  * Copyright (C) 2006-2013 wolfSSL Inc.
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 
00023 #ifdef HAVE_CONFIG_H
00024     #include <config.h>
00025 #endif
00026 
00027 #include <cyassl/ctaocrypt/settings.h>
00028 
00029 //#ifndef NO_SHA
00030 
00031 #include <cyassl/ctaocrypt/sha.h>
00032 #ifdef NO_INLINE
00033     #include <cyassl/ctaocrypt/misc.h>
00034 #else
00035     #include <ctaocrypt/src/misc.c>
00036 #endif
00037 
00038 
00039 #ifdef STM32F2_HASH
00040     /*
00041      * STM32F2 hardware SHA1 support through the STM32F2 standard peripheral
00042      * library. Documentation located in STM32F2xx Standard Peripheral Library
00043      * document (See note in README).
00044      */
00045     #include "stm32f2xx.h"
00046         #include "stm32f2xx_hash.h"
00047         
00048     void InitSha(Sha* sha)
00049     {
00050         /* STM32F2 struct notes:
00051          * sha->buffer  = first 4 bytes used to hold partial block if needed 
00052          * sha->buffLen = num bytes currently stored in sha->buffer
00053          * sha->loLen   = num bytes that have been written to STM32 FIFO
00054          */
00055         XMEMSET(sha->buffer, 0, SHA_REG_SIZE);
00056         sha->buffLen = 0;
00057         sha->loLen = 0;
00058 
00059         /* initialize HASH peripheral */
00060         HASH_DeInit();
00061 
00062         /* configure algo used, algo mode, datatype */
00063         HASH->CR &= ~ (HASH_CR_ALGO | HASH_CR_DATATYPE | HASH_CR_MODE);
00064         HASH->CR |= (HASH_AlgoSelection_SHA1 | HASH_AlgoMode_HASH 
00065                  | HASH_DataType_8b);
00066 
00067         /* reset HASH processor */
00068         HASH->CR |= HASH_CR_INIT;
00069     }
00070 
00071     void ShaUpdate(Sha* sha, const byte* data, word32 len)
00072     {
00073         word32 i = 0;
00074         word32 fill = 0;
00075         word32 diff = 0;
00076 
00077         /* if saved partial block is available */
00078         if (sha->buffLen) {
00079             fill = 4 - sha->buffLen;
00080 
00081             /* if enough data to fill, fill and push to FIFO */
00082             if (fill <= len) {
00083                 XMEMCPY((byte*)sha->buffer + sha->buffLen, data, fill);
00084                 HASH_DataIn(*(uint32_t*)sha->buffer);
00085 
00086                 data += fill;
00087                 len -= fill;
00088                 sha->loLen += 4;
00089                 sha->buffLen = 0;
00090             } else {
00091                 /* append partial to existing stored block */
00092                 XMEMCPY((byte*)sha->buffer + sha->buffLen, data, len);
00093                 sha->buffLen += len;
00094                 return;
00095             }
00096         }
00097        
00098         /* write input block in the IN FIFO */
00099         for(i = 0; i < len; i += 4)
00100         {
00101             diff = len - i;
00102             if ( diff < 4) {
00103                 /* store incomplete last block, not yet in FIFO */
00104                 XMEMSET(sha->buffer, 0, SHA_REG_SIZE);
00105                 XMEMCPY((byte*)sha->buffer, data, diff);
00106                 sha->buffLen = diff;
00107             } else {
00108                 HASH_DataIn(*(uint32_t*)data);
00109                 data+=4;
00110             }
00111         }
00112 
00113         /* keep track of total data length thus far */ 
00114         sha->loLen += (len - sha->buffLen);
00115     }
00116 
00117     void ShaFinal(Sha* sha, byte* hash)
00118     {
00119         __IO uint16_t nbvalidbitsdata = 0;
00120         
00121         /* finish reading any trailing bytes into FIFO */
00122         if (sha->buffLen) {
00123             HASH_DataIn(*(uint32_t*)sha->buffer);
00124             sha->loLen += sha->buffLen;
00125         }
00126 
00127         /* calculate number of valid bits in last word of input data */
00128         nbvalidbitsdata = 8 * (sha->loLen % SHA_REG_SIZE);
00129 
00130         /* configure number of valid bits in last word of the data */
00131         HASH_SetLastWordValidBitsNbr(nbvalidbitsdata);
00132 
00133         /* start HASH processor */
00134         HASH_StartDigest();
00135 
00136         /* wait until Busy flag == RESET */
00137         while (HASH_GetFlagStatus(HASH_FLAG_BUSY) != RESET) {}
00138 
00139         /* read message digest */
00140         sha->digest[0] = HASH->HR[0];
00141         sha->digest[1] = HASH->HR[1];
00142         sha->digest[2] = HASH->HR[2];
00143         sha->digest[3] = HASH->HR[3];
00144         sha->digest[4] = HASH->HR[4];
00145         
00146         ByteReverseWords(sha->digest, sha->digest, SHA_DIGEST_SIZE);
00147 
00148         XMEMCPY(hash, sha->digest, SHA_DIGEST_SIZE);
00149 
00150         InitSha(sha);  /* reset state */
00151     }
00152 
00153 #else /* CTaoCrypt software implementation */
00154 
00155 #ifndef min
00156 
00157     static INLINE word32 min(word32 a, word32 b)
00158     {
00159         return a > b ? b : a;
00160     }
00161 
00162 #endif /* min */
00163 
00164 
00165 void InitSha(Sha* sha)
00166 {
00167     sha->digest[0] = 0x67452301L;
00168     sha->digest[1] = 0xEFCDAB89L;
00169     sha->digest[2] = 0x98BADCFEL;
00170     sha->digest[3] = 0x10325476L;
00171     sha->digest[4] = 0xC3D2E1F0L;
00172 
00173     sha->buffLen = 0;
00174     sha->loLen   = 0;
00175     sha->hiLen   = 0;
00176 }
00177 
00178 #define blk0(i) (W[i] = sha->buffer[i])
00179 #define blk1(i) (W[i&15] = \
00180                    rotlFixed(W[(i+13)&15]^W[(i+8)&15]^W[(i+2)&15]^W[i&15],1))
00181 
00182 #define f1(x,y,z) (z^(x &(y^z)))
00183 #define f2(x,y,z) (x^y^z)
00184 #define f3(x,y,z) ((x&y)|(z&(x|y)))
00185 #define f4(x,y,z) (x^y^z)
00186 
00187 /* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
00188 #define R0(v,w,x,y,z,i) z+= f1(w,x,y) + blk0(i) + 0x5A827999+ \
00189                         rotlFixed(v,5); w = rotlFixed(w,30);
00190 #define R1(v,w,x,y,z,i) z+= f1(w,x,y) + blk1(i) + 0x5A827999+ \
00191                         rotlFixed(v,5); w = rotlFixed(w,30);
00192 #define R2(v,w,x,y,z,i) z+= f2(w,x,y) + blk1(i) + 0x6ED9EBA1+ \
00193                         rotlFixed(v,5); w = rotlFixed(w,30);
00194 #define R3(v,w,x,y,z,i) z+= f3(w,x,y) + blk1(i) + 0x8F1BBCDC+ \
00195                         rotlFixed(v,5); w = rotlFixed(w,30);
00196 #define R4(v,w,x,y,z,i) z+= f4(w,x,y) + blk1(i) + 0xCA62C1D6+ \
00197                         rotlFixed(v,5); w = rotlFixed(w,30);
00198 
00199 
00200 static void Transform(Sha* sha)
00201 {
00202     word32 W[SHA_BLOCK_SIZE / sizeof(word32)];
00203 
00204     /* Copy context->state[] to working vars */ 
00205     word32 a = sha->digest[0];
00206     word32 b = sha->digest[1];
00207     word32 c = sha->digest[2];
00208     word32 d = sha->digest[3];
00209     word32 e = sha->digest[4];
00210 
00211 #ifdef USE_SLOW_SHA
00212     word32 t, i;
00213 
00214     for (i = 0; i < 16; i++) {
00215         R0(a, b, c, d, e, i);
00216         t = e; e = d; d = c; c = b; b = a; a = t;
00217     }
00218 
00219     for (; i < 20; i++) {
00220         R1(a, b, c, d, e, i);
00221         t = e; e = d; d = c; c = b; b = a; a = t;
00222     }
00223 
00224     for (; i < 40; i++) {
00225         R2(a, b, c, d, e, i);
00226         t = e; e = d; d = c; c = b; b = a; a = t;
00227     }
00228 
00229     for (; i < 60; i++) {
00230         R3(a, b, c, d, e, i);
00231         t = e; e = d; d = c; c = b; b = a; a = t;
00232     }
00233 
00234     for (; i < 80; i++) {
00235         R4(a, b, c, d, e, i);
00236         t = e; e = d; d = c; c = b; b = a; a = t;
00237     }
00238 #else
00239     /* nearly 1 K bigger in code size but 25% faster  */
00240     /* 4 rounds of 20 operations each. Loop unrolled. */
00241     R0(a,b,c,d,e, 0); R0(e,a,b,c,d, 1); R0(d,e,a,b,c, 2); R0(c,d,e,a,b, 3);
00242     R0(b,c,d,e,a, 4); R0(a,b,c,d,e, 5); R0(e,a,b,c,d, 6); R0(d,e,a,b,c, 7);
00243     R0(c,d,e,a,b, 8); R0(b,c,d,e,a, 9); R0(a,b,c,d,e,10); R0(e,a,b,c,d,11);
00244     R0(d,e,a,b,c,12); R0(c,d,e,a,b,13); R0(b,c,d,e,a,14); R0(a,b,c,d,e,15);
00245 
00246     R1(e,a,b,c,d,16); R1(d,e,a,b,c,17); R1(c,d,e,a,b,18); R1(b,c,d,e,a,19);
00247 
00248     R2(a,b,c,d,e,20); R2(e,a,b,c,d,21); R2(d,e,a,b,c,22); R2(c,d,e,a,b,23);
00249     R2(b,c,d,e,a,24); R2(a,b,c,d,e,25); R2(e,a,b,c,d,26); R2(d,e,a,b,c,27);
00250     R2(c,d,e,a,b,28); R2(b,c,d,e,a,29); R2(a,b,c,d,e,30); R2(e,a,b,c,d,31);
00251     R2(d,e,a,b,c,32); R2(c,d,e,a,b,33); R2(b,c,d,e,a,34); R2(a,b,c,d,e,35);
00252     R2(e,a,b,c,d,36); R2(d,e,a,b,c,37); R2(c,d,e,a,b,38); R2(b,c,d,e,a,39);
00253 
00254     R3(a,b,c,d,e,40); R3(e,a,b,c,d,41); R3(d,e,a,b,c,42); R3(c,d,e,a,b,43);
00255     R3(b,c,d,e,a,44); R3(a,b,c,d,e,45); R3(e,a,b,c,d,46); R3(d,e,a,b,c,47);
00256     R3(c,d,e,a,b,48); R3(b,c,d,e,a,49); R3(a,b,c,d,e,50); R3(e,a,b,c,d,51);
00257     R3(d,e,a,b,c,52); R3(c,d,e,a,b,53); R3(b,c,d,e,a,54); R3(a,b,c,d,e,55);
00258     R3(e,a,b,c,d,56); R3(d,e,a,b,c,57); R3(c,d,e,a,b,58); R3(b,c,d,e,a,59);
00259 
00260     R4(a,b,c,d,e,60); R4(e,a,b,c,d,61); R4(d,e,a,b,c,62); R4(c,d,e,a,b,63);
00261     R4(b,c,d,e,a,64); R4(a,b,c,d,e,65); R4(e,a,b,c,d,66); R4(d,e,a,b,c,67);
00262     R4(c,d,e,a,b,68); R4(b,c,d,e,a,69); R4(a,b,c,d,e,70); R4(e,a,b,c,d,71);
00263     R4(d,e,a,b,c,72); R4(c,d,e,a,b,73); R4(b,c,d,e,a,74); R4(a,b,c,d,e,75);
00264     R4(e,a,b,c,d,76); R4(d,e,a,b,c,77); R4(c,d,e,a,b,78); R4(b,c,d,e,a,79);
00265 #endif
00266 
00267     /* Add the working vars back into digest state[] */
00268     sha->digest[0] += a;
00269     sha->digest[1] += b;
00270     sha->digest[2] += c;
00271     sha->digest[3] += d;
00272     sha->digest[4] += e;
00273 }
00274 
00275 
00276 static INLINE void AddLength(Sha* sha, word32 len)
00277 {
00278     word32 tmp = sha->loLen;
00279     if ( (sha->loLen += len) < tmp)
00280         sha->hiLen++;                       /* carry low to high */
00281 }
00282 
00283 
00284 void ShaUpdate(Sha* sha, const byte* data, word32 len)
00285 {
00286     /* do block size increments */
00287     byte* local = (byte*)sha->buffer;
00288 
00289     while (len) {
00290         word32 add = min(len, SHA_BLOCK_SIZE - sha->buffLen);
00291         XMEMCPY(&local[sha->buffLen], data, add);
00292 
00293         sha->buffLen += add;
00294         data         += add;
00295         len          -= add;
00296 
00297         if (sha->buffLen == SHA_BLOCK_SIZE) {
00298             #ifdef LITTLE_ENDIAN_ORDER
00299                 ByteReverseBytes(local, local, SHA_BLOCK_SIZE);
00300             #endif
00301             Transform(sha);
00302             AddLength(sha, SHA_BLOCK_SIZE);
00303             sha->buffLen = 0;
00304         }
00305     }
00306 }
00307 
00308 
00309 void ShaFinal(Sha* sha, byte* hash)
00310 {
00311     byte* local = (byte*)sha->buffer;
00312 
00313     AddLength(sha, sha->buffLen);               /* before adding pads */
00314 
00315     local[sha->buffLen++] = 0x80;  /* add 1 */
00316 
00317     /* pad with zeros */
00318     if (sha->buffLen > SHA_PAD_SIZE) {
00319         XMEMSET(&local[sha->buffLen], 0, SHA_BLOCK_SIZE - sha->buffLen);
00320         sha->buffLen += SHA_BLOCK_SIZE - sha->buffLen;
00321 
00322         #ifdef LITTLE_ENDIAN_ORDER
00323             ByteReverseBytes(local, local, SHA_BLOCK_SIZE);
00324         #endif
00325         Transform(sha);
00326         sha->buffLen = 0;
00327     }
00328     XMEMSET(&local[sha->buffLen], 0, SHA_PAD_SIZE - sha->buffLen);
00329    
00330     /* put lengths in bits */
00331     sha->hiLen = (sha->loLen >> (8*sizeof(sha->loLen) - 3)) + 
00332                  (sha->hiLen << 3);
00333     sha->loLen = sha->loLen << 3;
00334 
00335     /* store lengths */
00336     #ifdef LITTLE_ENDIAN_ORDER
00337         ByteReverseBytes(local, local, SHA_BLOCK_SIZE);
00338     #endif
00339     /* ! length ordering dependent on digest endian type ! */
00340     XMEMCPY(&local[SHA_PAD_SIZE], &sha->hiLen, sizeof(word32));
00341     XMEMCPY(&local[SHA_PAD_SIZE + sizeof(word32)], &sha->loLen, sizeof(word32));
00342 
00343     Transform(sha);
00344     #ifdef LITTLE_ENDIAN_ORDER
00345         ByteReverseWords(sha->digest, sha->digest, SHA_DIGEST_SIZE);
00346     #endif
00347     XMEMCPY(hash, sha->digest, SHA_DIGEST_SIZE);
00348 
00349     InitSha(sha);  /* reset state */
00350 }
00351 
00352 #endif /* STM32F2_HASH */
00353 
00354 //#endif /* NO_SHA */