*
* \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 1.16 2007/02/15 13:29:49 asterix
+ *#* Add MD2_DIGEST_LEN macro.
+ *#*
+ *#* 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.
+ *#*
*#* Revision 1.11 2007/02/02 18:15:31 asterix
*#* Add function MD2_test. Fix bug in md2_update function.
*#*
#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 uint8_t 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 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
+ /**
+ * 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
{
for(int j = 0; j < COMPUTE_ARRAY_LEN; j++)
{
- compute_array[j] ^= md2_perm [t];
+ compute_array[j] ^= MD2_PERM(t);
t = compute_array[j];
}
for(i = 0; i < CONFIG_MD2_BLOCK_LEN; i++)
{
- checksum[i] ^= md2_perm [block[i] ^ t];
+ checksum[i] ^= MD2_PERM(block[i] ^ t);
t = checksum[i];
}
* MD2 test fuction.
* This function test MD2 algorithm with a standard string specified
* in RFC 1319.
- *
+ *
* \note This test work with official array of 256 byte pemutation
* contructed from digits of pi, defined in the RFC 1319.
*
Md2Context context;
- const char *test[] =
+ const char *test[] =
{
- "",
+ "",
"message digest",
"abcdefghijklmnopqrstuvwxyz",
"12345678901234567890123456789012345678901234567890123456789012345678901234567890"
};
-
+
const uint8_t *result[] = {
"\x83\x50\xe5\xa3\xe2\x4c\x15\x3d\xf2\x27\x5c\x9f\x80\x69\x27\x73",
"\xd5\x97\x6f\x79\xd8\x3d\x3a\x0d\xc9\x80\x6c\x3c\x66\xf3\xef\xd8",
};
-
+
for (int i = 0; i < countof(test); i++)
{
md2_init(&context);
md2_update(&context, test[i], strlen(test[i]));
- if(memcmp(result[i], md2_end(&context), CONFIG_MD2_BLOCK_LEN))
- return false;
+ if(memcmp(result[i], md2_end(&context), MD2_DIGEST_LEN))
+ return false;
}
return true;
#include <stdio.h>
int main(int argc, char * argv[])
{
+
if(md2_test())
printf("MD2 algorithm work well!\n");
else
printf("MD2 algorithm doesn't work well.\n");
-
+
}
#endif