56 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			56 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #include <tommath.h>
 | |
| #ifdef BN_MP_READ_UNSIGNED_BIN_C
 | |
| /* LibTomMath, multiple-precision integer library -- Tom St Denis
 | |
|  *
 | |
|  * LibTomMath is a library that provides multiple-precision
 | |
|  * integer arithmetic as well as number theoretic functionality.
 | |
|  *
 | |
|  * The library was designed directly after the MPI library by
 | |
|  * Michael Fromberger but has been written from scratch with
 | |
|  * additional optimizations in place.
 | |
|  *
 | |
|  * The library is free for all purposes without any express
 | |
|  * guarantee it works.
 | |
|  *
 | |
|  * Tom St Denis, tomstdenis@gmail.com, http://libtom.org
 | |
|  */
 | |
| 
 | |
| /* reads a unsigned char array, assumes the msb is stored first [big endian] */
 | |
| int mp_read_unsigned_bin (mp_int * a, const unsigned char *b, int c)
 | |
| {
 | |
|   int     res;
 | |
| 
 | |
|   /* make sure there are at least two digits */
 | |
|   if (a->alloc < 2) {
 | |
|      if ((res = mp_grow(a, 2)) != MP_OKAY) {
 | |
|         return res;
 | |
|      }
 | |
|   }
 | |
| 
 | |
|   /* zero the int */
 | |
|   mp_zero (a);
 | |
| 
 | |
|   /* read the bytes in */
 | |
|   while (c-- > 0) {
 | |
|     if ((res = mp_mul_2d (a, 8, a)) != MP_OKAY) {
 | |
|       return res;
 | |
|     }
 | |
| 
 | |
| #ifndef MP_8BIT
 | |
|       a->dp[0] |= *b++;
 | |
|       a->used += 1;
 | |
| #else
 | |
|       a->dp[0] = (*b & MP_MASK);
 | |
|       a->dp[1] |= ((*b++ >> 7U) & 1);
 | |
|       a->used += 2;
 | |
| #endif
 | |
|   }
 | |
|   mp_clamp (a);
 | |
|   return MP_OKAY;
 | |
| }
 | |
| #endif
 | |
| 
 | |
| /* $Source$ */
 | |
| /* $Revision$ */
 | |
| /* $Date$ */
 |