+bad optimisation (doesn't improve anything)

[avr-crypto-lib.git] / md5.c

diff --git a/md5.c b/md5.c
index d26c806e04d29573ee74e023b394cf65c33c1ca5..5c7bb9a6d67af119ae3938dc03baa1cd73ae09ae 100644 (file)
--- a/md5.c
+++ b/md5.c
@@ -1,15 +1,145 @@
 /* 
- * File:       md5.h
- * Author:     Daniel Otte
- * Date:       31.07.2006
- * License: GPL
- * Description: Implementation of the MD5 hash algorithm as described in RFC 1321
+ * \file       md5.c
+ * \author     Daniel Otte
+ * \date       31.07.2006
+ * \par License:
+ * GPL
+ * \brief Implementation of the MD5 hash algorithm as described in RFC 1321
  * 
  */
 
  #include "md5.h"
+ #include "md5_sbox.h"
+ #include "uart.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;
+}
  
- 
\ No newline at end of file
+uint32_t md5_F(uint32_t x, uint32_t y, uint32_t z){
+       return ((x&y)|((~x)&z));
+}
+
+uint32_t md5_G(uint32_t x, uint32_t y, uint32_t z){
+       return ((x&z)|((~z)&y));
+}
+
+uint32_t md5_H(uint32_t x, uint32_t y, uint32_t z){
+       return (x^y^z);
+}
+
+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))))  
+
+void md5_core(uint32_t* a, uint8_t as, void* block, uint8_t k, 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[]={'*', '-', '+', '~'};
+       uart_putstr("\r\n DBG: md5_core [");
+       uart_putc(funcc[fi]);
+       uart_hexdump(&as, 1); uart_putc(' ');
+       uart_hexdump(&k, 1); uart_putc(' ');
+       uart_hexdump(&s, 1); uart_putc(' ');
+       uart_hexdump(&i, 1); uart_putc(']');
+#endif 
+       t = a[as] + funcs[fi](a[(as+1)&3], a[(as+2)&3], a[(as+3)&3]) + ((uint32_t*)block)[k] + md5_T[i] ;
+       a[as]=a[(as+1)&3] + ROTL32(t, s);
+}
+
+void md5_nextBlock(md5_ctx_t *state, void* block){
+       uint32_t        a[4];
+       uint8_t         m,n,i=0;
+       /* this requires other mixed sboxes */
+#ifdef DEBUG
+       uart_putstr("\r\n DBG: md5_nextBlock: block:\r\n");
+       uart_hexdump(block, 16);        uart_putstr("\r\n");
+       uart_hexdump(block+16, 16);     uart_putstr("\r\n");
+       uart_hexdump(block+32, 16);     uart_putstr("\r\n");
+       uart_hexdump(block+48, 16);     uart_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};
+       for(m=0;m<4;++m){
+               for(n=0;n<4;++n){
+                       md5_core(a, 4-n, block, m*4+n, s1t[n],i++,0);
+               }
+       }
+       /* round 2 */
+       uint8_t s2t[]={5,9,14,20};
+       for(m=0;m<4;++m){
+               for(n=0;n<4;++n){
+                       md5_core(a, 4-n, block, (1+m*4+n*5)&0xf, s2t[n],i++,1);
+               }
+       }
+       /* round 3 */
+       uint8_t s3t[]={4,11,16,23};
+       for(m=0;m<4;++m){
+               for(n=0;n<4;++n){
+                       md5_core(a, 4-n, block, (5-m*4+n*3)&0xf, s3t[n],i++,2);
+               }
+       }
+       /* round 4 */
+       uint8_t s4t[]={6,10,15,21};
+       for(m=0;m<4;++m){
+               for(n=0;n<4;++n){
+                       md5_core(a, 4-n, block, (0-m*4+n*7)&0xf, 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, void* block, uint16_t length){
+       uint16_t l;
+       uint8_t b[64];
+       while (length >= 512){
+               md5_nextBlock(state, block);
+               length -= 512;
+               block = ((uint8_t*)block) + 512/8;
+       }
+       memset(b, 0, 64);
+       memcpy(b, block, length/8);
+       /* insert padding one */
+       l=length/8;
+       if(length%8){
+               uint8_t t;
+               t = ((uint8_t*)block)[l];
+               t |= (0x80>>(length%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);
+       }
+       *((uint64_t*)&b[64-sizeof(uint64_t)]) = (state->counter * 512) + length;
+       md5_nextBlock(state, b);
+}