X-Git-Url: https://codewiz.org/gitweb?a=blobdiff_plain;f=algos%2Fmd2.c;h=edd9fa8c2a54df0ce4652544302f1276a9e7ac0e;hb=43cc9dde2073972fc586ee95d2de5797d654f6cb;hp=4eee4ecd5e60ea82ce1905ab9bebafe0e22f39ff;hpb=48e9459a1f736a5c256abff5ee4cd11ffad38602;p=bertos.git

diff --git a/algos/md2.c b/algos/md2.c
index 4eee4ecd..edd9fa8c 100755
--- a/algos/md2.c
+++ b/algos/md2.c
@@ -7,12 +7,28 @@
  *
  * \brief MD2 Message-Digest algorithm.
  *
+ * The MD2 algorithm work with a constant array of 256 permutationt
+ * defined in RFC1319. If you don't want to use a standard array of 
+ * permutatione you can use a md2_perm() function that generate an 
+ * array of 256 "casual" permutation. To swich from a standard array 
+ * to md2_perm function you must chanche CONFIG_MD2_STD_PERM defined in 
+ * appconfig.h.
+ * If you need to store array in program memory you must define 
+ * a macro _PROGMEM (for more info see mware/pgm.h).
+ *
+ *
  * \version $Id$
  * \author Daniele Basile <asterix@develer.com>
  */
 
 /*#*
  *#* $Log$
+ *#* Revision 1.15  2007/02/06 15:53:34  asterix
+ *#* Add ROTR macro in m2d_perm, add comments, typos.
+ *#*
+ *#* Revision 1.13  2007/02/05 18:44:42  asterix
+ *#* Add md2_perm function.
+ *#*
  *#* Revision 1.12  2007/02/05 16:52:44  asterix
  *#* Add define for harvard architecture.
  *#*
@@ -44,42 +60,69 @@
 #include <string.h>           //memset(), memcpy();
 #include <cfg/compiler.h>
 #include <cfg/debug.h>        //ASSERT()
-#include <cfg/macros.h>       //MIN(), countof();
+#include <cfg/macros.h>       //MIN(), countof(), ROTR();
 #include <mware/pgm.h>   
 
 
-/*
- * Official array of 256 byte pemutation contructed from digits of pi, defined
- * in the RFC 1319.
- */
-static const uint8_t PROGMEM md2_perm[256] = 
-{
-  41, 46, 67, 201, 162, 216, 124, 1, 61, 54, 84, 161, 236, 240, 6,
-  19, 98, 167, 5, 243, 192, 199, 115, 140, 152, 147, 43, 217, 188,
-  76, 130, 202, 30, 155, 87, 60, 253, 212, 224, 22, 103, 66, 111, 24,
-  138, 23, 229, 18, 190, 78, 196, 214, 218, 158, 222, 73, 160, 251,
-  245, 142, 187, 47, 238, 122, 169, 104, 121, 145, 21, 178, 7, 63,
-  148, 194, 16, 137, 11, 34, 95, 33, 128, 127, 93, 154, 90, 144, 50,
-  39, 53, 62, 204, 231, 191, 247, 151, 3, 255, 25, 48, 179, 72, 165,
-  181, 209, 215, 94, 146, 42, 172, 86, 170, 198, 79, 184, 56, 210,
-  150, 164, 125, 182, 118, 252, 107, 226, 156, 116, 4, 241, 69, 157,
-  112, 89, 100, 113, 135, 32, 134, 91, 207, 101, 230, 45, 168, 2, 27,
-  96, 37, 173, 174, 176, 185, 246, 28, 70, 97, 105, 52, 64, 126, 15,
-  85, 71, 163, 35, 221, 81, 175, 58, 195, 92, 249, 206, 186, 197,
-  234, 38, 44, 83, 13, 110, 133, 40, 132, 9, 211, 223, 205, 244, 65,
-  129, 77, 82, 106, 220, 55, 200, 108, 193, 171, 250, 36, 225, 123,
-  8, 12, 189, 177, 74, 120, 136, 149, 139, 227, 99, 232, 109, 233,
-  203, 213, 254, 59, 0, 29, 57, 242, 239, 183, 14, 102, 88, 208, 228,
-  166, 119, 114, 248, 235, 117, 75, 10, 49, 68, 80, 180, 143, 237,
-  31, 26, 219, 153, 141, 51, 159, 17, 131, 20
-};
-
-#if CPU_HARVARD
-	#define	MD2_PERM(x) pgm_read_char(&md2_perm[x]) //Read from program memory, if CPU is harvard
+#if CONFIG_MD2_STD_PERM
+	/*
+	* Official array of 256 byte pemutation contructed from digits of pi, defined
+	* in the RFC 1319.
+	*/
+	static const uint8_t PGM_ATTR md2_perm[256] = 
+	{
+	41, 46, 67, 201, 162, 216, 124, 1, 61, 54, 84, 161, 236, 240, 6,
+	19, 98, 167, 5, 243, 192, 199, 115, 140, 152, 147, 43, 217, 188,
+	76, 130, 202, 30, 155, 87, 60, 253, 212, 224, 22, 103, 66, 111, 24,
+	138, 23, 229, 18, 190, 78, 196, 214, 218, 158, 222, 73, 160, 251,
+	245, 142, 187, 47, 238, 122, 169, 104, 121, 145, 21, 178, 7, 63,
+	148, 194, 16, 137, 11, 34, 95, 33, 128, 127, 93, 154, 90, 144, 50,
+	39, 53, 62, 204, 231, 191, 247, 151, 3, 255, 25, 48, 179, 72, 165,
+	181, 209, 215, 94, 146, 42, 172, 86, 170, 198, 79, 184, 56, 210,
+	150, 164, 125, 182, 118, 252, 107, 226, 156, 116, 4, 241, 69, 157,
+	112, 89, 100, 113, 135, 32, 134, 91, 207, 101, 230, 45, 168, 2, 27,
+	96, 37, 173, 174, 176, 185, 246, 28, 70, 97, 105, 52, 64, 126, 15,
+	85, 71, 163, 35, 221, 81, 175, 58, 195, 92, 249, 206, 186, 197,
+	234, 38, 44, 83, 13, 110, 133, 40, 132, 9, 211, 223, 205, 244, 65,
+	129, 77, 82, 106, 220, 55, 200, 108, 193, 171, 250, 36, 225, 123,
+	8, 12, 189, 177, 74, 120, 136, 149, 139, 227, 99, 232, 109, 233,
+	203, 213, 254, 59, 0, 29, 57, 242, 239, 183, 14, 102, 88, 208, 228,
+	166, 119, 114, 248, 235, 117, 75, 10, 49, 68, 80, 180, 143, 237,
+	31, 26, 219, 153, 141, 51, 159, 17, 131, 20
+	};
+
+	#define MD2_PERM(x) PGM_READ_CHAR(&md2_perm[x])
 #else
-	#define	MD2_PERM(x) md2_perm[x]                 //Normaly from a const array.
+	/**
+	 * Md2_perm() function generate an array of 256 "casual" permutation.
+	 */
+	
+	/**
+	 * Costant define for computing an array of 256 "casual" permutation.
+	 * \{
+	 */
+	#define K1 5
+	#define K2 3
+	#define R  2
+	#define X  172
+	/*\}*/
+
+	static uint8_t md2_perm(uint8_t i)
+	{
+
+		i = i * K1;
+		i = ROTR(i, R);
+		i ^=  X;
+		i = i * K2;
+
+		return i;
+	}
+
+	#define MD2_PERM(x) md2_perm(x)
+		
 #endif
 
+
 /**
  * Pad function. Put len_pad unsigned char in
  * input block.