--- /dev/null
+/* sha2_small_common.c */
+/*
+ This file is part of the ARM-Crypto-Lib.
+ Copyright (C) 2006-2011 Daniel Otte (daniel.otte@rub.de)
+
+ 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, either version 3 of the License, or
+ (at your option) any later version.
+
+ 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. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <stdint.h>
+#include <string.h>
+#include <avr/pgmspace.h>
+#include "sha2_small_common.h"
+
+
+#define LITTLE_ENDIAN
+
+/**
+ * rotate x right by n positions
+ */
+static
+uint32_t rotr32( uint32_t x, uint8_t n){
+ return ((x>>n) | (x<<(32-n)));
+}
+
+static
+uint32_t rotl32( uint32_t x, uint8_t n){
+ return ((x<<n) | (x>>(32-n)));
+}
+
+
+/*************************************************************************/
+
+// #define CHANGE_ENDIAN32(x) (((x)<<24) | ((x)>>24) | (((x)& 0x0000ff00)<<8) | (((x)& 0x00ff0000)>>8))
+static
+uint32_t change_endian32(uint32_t x){
+ return (((x)<<24) | ((x)>>24) | (((x)& 0x0000ff00)<<8) | (((x)& 0x00ff0000)>>8));
+}
+
+
+/* sha256 functions as macros for speed and size, cause they are called only once */
+
+#define CH(x,y,z) (((x)&(y)) ^ ((~(x))&(z)))
+#define MAJ(x,y,z) (((x)&(y)) ^ ((x)&(z)) ^ ((y)&(z)))
+
+#define SIGMA_0(x) (rotr32((x), 2) ^ rotr32((x),13) ^ rotl32((x),10))
+#define SIGMA_1(x) (rotr32((x), 6) ^ rotr32((x),11) ^ rotl32((x),7))
+#define SIGMA_a(x) (rotr32((x), 7) ^ rotl32((x),14) ^ ((x)>>3))
+#define SIGMA_b(x) (rotl32((x),15) ^ rotl32((x),13) ^ ((x)>>10))
+
+const
+uint32_t k[] PROGMEM = {
+ 0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
+ 0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3, 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
+ 0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
+ 0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
+ 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13, 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
+ 0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
+ 0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
+ 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
+};
+
+
+
+/**
+ * block must be, 512, Bit = 64, Byte, long !!!
+ */
+void sha2_small_common_nextBlock (sha2_small_common_ctx_t *state, const void* block){
+ uint32_t w[16], wx;
+ uint8_t i;
+ uint32_t a[8],t1,t2;
+
+ /* init w */
+#if defined LITTLE_ENDIAN
+ for (i=0; i<16; ++i){
+ w[i]= change_endian32(((uint32_t*)block)[i]);
+ }
+#elif defined BIG_ENDIAN
+ memcpy((void*)w, block, 64);
+#endif
+/*
+ for (i=16; i<64; ++i){
+ w[i] = SIGMA_b(w[i-2]) + w[i-7] + SIGMA_a(w[i-15]) + w[i-16];
+ }
+*/
+/* init working variables */
+ memcpy((void*)a,(void*)(state->h), 8*4);
+
+/* do the, fun stuff, */
+ for (i=0; i<64; ++i){
+ if(i<16){
+ wx = w[i];
+ }else{
+ wx = SIGMA_b(w[14]) + w[9] + SIGMA_a(w[1]) + w[0];
+ memmove(&(w[0]), &(w[1]), 15*4);
+ w[15] = wx;
+ }
+ t1 = a[7] + SIGMA_1(a[4]) + CH(a[4],a[5],a[6]) + pgm_read_dword(&k[i]) + wx;
+ t2 = SIGMA_0(a[0]) + MAJ(a[0],a[1],a[2]);
+ memmove(&(a[1]), &(a[0]), 7*4); /* a[7]=a[6]; a[6]=a[5]; a[5]=a[4]; a[4]=a[3]; a[3]=a[2]; a[2]=a[1]; a[1]=a[0]; */
+ a[4] += t1;
+ a[0] = t1 + t2;
+ }
+
+/* update, the, state, */
+ for (i=0; i<8; ++i){
+ state->h[i] += a[i];
+ }
+ state->length += 1;
+}
+
+
+void sha2_small_common_lastBlock(sha2_small_common_ctx_t *state, const void* block, uint16_t length_b){
+ uint8_t lb[512/8]; /* local block */
+ uint64_t len;
+ while(length_b>=512){
+ sha2_small_common_nextBlock(state, block);
+ length_b -= 512;
+ block = (uint8_t*)block+64;
+ }
+ len = state->length*512 + length_b;
+ memset(lb, 0, 64);
+ memcpy(lb, block, (length_b+7)/8);
+
+ /* set the final one bit */
+ lb[length_b/8] |= 0x80>>(length_b & 0x7);
+ /* pad with zeros */
+ if (length_b>=512-64){ /* not enouth space for 64bit length value */
+ sha2_small_common_nextBlock(state, lb);
+ memset(lb, 0, 64);
+ }
+ /* store the 64bit length value */
+#if defined LITTLE_ENDIAN
+ /* this is now rolled up */
+ uint8_t i;
+ i=7;
+ do{
+ lb[63-i] = ((uint8_t*)&len)[i];
+ }while(i--);
+#elif defined BIG_ENDIAN
+ *((uint64_t)&(lb[56])) = len;
+#endif
+ sha2_small_common_nextBlock(state, lb);
+}
+
projects / avr-crypto-lib.git / blobdiff