--- /dev/null
+/* md5.c */
+/*
+ This file is part of the AVR-Crypto-Lib.
+ Copyright (C) 2008 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/>.
+*/
+/*
+ * \file md5.c
+ * \author Daniel Otte
+ * \date 2006-07-31
+ * \license GPLv3 or later
+ * \brief Implementation of the MD5 hash algorithm as described in RFC 1321
+ *
+ */
+
+ #include "md5.h"
+ #include "md5_sbox.h"
+ #include "cli.h"
+ #include <stdint.h>
+ #include <string.h>
+
+ #undef DEBUG
+
+void md5_init(md5_ctx_t *s){
+ s->counter = 0;
+ s->a[0] = 0x67452301;
+ s->a[1] = 0xefcdab89;
+ s->a[2] = 0x98badcfe;
+ s->a[3] = 0x10325476;
+}
+
+static
+uint32_t md5_F(uint32_t x, uint32_t y, uint32_t z){
+ return ((x&y)|((~x)&z));
+}
+
+static
+uint32_t md5_G(uint32_t x, uint32_t y, uint32_t z){
+ return ((x&z)|((~z)&y));
+}
+
+static
+uint32_t md5_H(uint32_t x, uint32_t y, uint32_t z){
+ return (x^y^z);
+}
+
+static
+uint32_t md5_I(uint32_t x, uint32_t y, uint32_t z){
+ return (y ^ (x | (~z)));
+}
+
+typedef uint32_t md5_func_t(uint32_t, uint32_t, uint32_t);
+
+#define ROTL32(x,n) (((x)<<(n)) | ((x)>>(32-(n))))
+
+static
+void md5_core(uint32_t* a, void* block, uint8_t as, uint8_t s, uint8_t i, uint8_t fi){
+ uint32_t t;
+ md5_func_t* funcs[]={md5_F, md5_G, md5_H, md5_I};
+ as &= 0x3;
+ /* a = b + ((a + F(b,c,d) + X[k] + T[i]) <<< s). */
+#ifdef DEBUG
+ char funcc[]={'*', '-', '+', '~'};
+ cli_putstr("\r\n DBG: md5_core [");
+ cli_putc(funcc[fi]);
+ cli_hexdump(&as, 1); cli_putc(' ');
+ cli_hexdump(&k, 1); cli_putc(' ');
+ cli_hexdump(&s, 1); cli_putc(' ');
+ cli_hexdump(&i, 1); cli_putc(']');
+#endif
+ t = a[as] + funcs[fi](a[(as+1)&3], a[(as+2)&3], a[(as+3)&3])
+ + *((uint32_t*)block) + pgm_read_dword(md5_T+i) ;
+ a[as]=a[(as+1)&3] + ROTL32(t, s);
+}
+
+void md5_nextBlock(md5_ctx_t *state, const void* block){
+ uint32_t a[4];
+ uint8_t m,n,i=0;
+ /* this requires other mixed sboxes */
+#ifdef DEBUG
+ cli_putstr("\r\n DBG: md5_nextBlock: block:\r\n");
+ cli_hexdump(block, 16); cli_putstr("\r\n");
+ cli_hexdump(block+16, 16); cli_putstr("\r\n");
+ cli_hexdump(block+32, 16); cli_putstr("\r\n");
+ cli_hexdump(block+48, 16); cli_putstr("\r\n");
+#endif
+
+ a[0]=state->a[0];
+ a[1]=state->a[1];
+ a[2]=state->a[2];
+ a[3]=state->a[3];
+
+ /* round 1 */
+ uint8_t s1t[]={7,12,17,22}; // 1,-1 1,4 2,-1 3,-2
+ for(m=0;m<4;++m){
+ for(n=0;n<4;++n){
+ md5_core(a, &(((uint32_t*)block)[m*4+n]), 4-n, s1t[n],i++,0);
+ }
+ }
+ /* round 2 */
+ uint8_t s2t[]={5,9,14,20}; // 1,-3 1,1 2,-2 2,4
+ for(m=0;m<4;++m){
+ for(n=0;n<4;++n){
+ md5_core(a, &(((uint32_t*)block)[(1+m*4+n*5)&0xf]), 4-n, s2t[n],i++,1);
+ }
+ }
+ /* round 3 */
+ uint8_t s3t[]={4,11,16,23}; // 0,4 1,3 2,0 3,-1
+ for(m=0;m<4;++m){
+ for(n=0;n<4;++n){
+ md5_core(a, &(((uint32_t*)block)[(5-m*4+n*3)&0xf]), 4-n, s3t[n],i++,2);
+ }
+ }
+ /* round 4 */
+ uint8_t s4t[]={6,10,15,21}; // 1,-2 1,2 2,-1 3,-3
+ for(m=0;m<4;++m){
+ for(n=0;n<4;++n){
+ md5_core(a, &(((uint32_t*)block)[(0-m*4+n*7)&0xf]), 4-n, s4t[n],i++,3);
+ }
+ }
+ state->a[0] += a[0];
+ state->a[1] += a[1];
+ state->a[2] += a[2];
+ state->a[3] += a[3];
+ state->counter++;
+}
+
+void md5_lastBlock(md5_ctx_t *state, const void* block, uint16_t length_b){
+ uint16_t l;
+ uint8_t b[64];
+ while (length_b >= 512){
+ md5_nextBlock(state, block);
+ length_b -= 512;
+ block = ((uint8_t*)block) + 512/8;
+ }
+ memset(b, 0, 64);
+ memcpy(b, block, length_b/8);
+ /* insert padding one */
+ l=length_b/8;
+ if(length_b%8){
+ uint8_t t;
+ t = ((uint8_t*)block)[l];
+ t |= (0x80>>(length_b%8));
+ b[l]=t;
+ }else{
+ b[l]=0x80;
+ }
+ /* insert length value */
+ if(l+sizeof(uint64_t) >= 512/8){
+ md5_nextBlock(state, b);
+ state->counter--;
+ memset(b, 0, 64-8);
+ }
+ *((uint64_t*)&b[64-sizeof(uint64_t)]) = (state->counter * 512) + length_b;
+ md5_nextBlock(state, b);
+}
+
+void md5_ctx2hash(md5_hash_t* dest, const md5_ctx_t* state){
+ memcpy(dest, state->a, MD5_HASH_BYTES);
+}
+
+void md5(md5_hash_t* dest, const void* msg, uint32_t length_b){
+ md5_ctx_t ctx;
+ md5_init(&ctx);
+ while(length_b>=MD5_BLOCK_BITS){
+ md5_nextBlock(&ctx, msg);
+ msg = (uint8_t*)msg + MD5_BLOCK_BYTES;
+ length_b -= MD5_BLOCK_BITS;
+ }
+ md5_lastBlock(&ctx, msg, length_b);
+ md5_ctx2hash(dest, &ctx);
+}
+
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