18 lines
		
	
	
		
			498 B
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			18 lines
		
	
	
		
			498 B
		
	
	
	
		
			C
		
	
	
	
	
	
| #include "tommath_private.h"
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| #ifdef BN_MP_REDUCE_SETUP_C
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| /* LibTomMath, multiple-precision integer library -- Tom St Denis */
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| /* SPDX-License-Identifier: Unlicense */
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| 
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| /* pre-calculate the value required for Barrett reduction
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|  * For a given modulus "b" it calulates the value required in "a"
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|  */
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| mp_err mp_reduce_setup(mp_int *a, const mp_int *b)
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| {
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|    mp_err err;
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|    if ((err = mp_2expt(a, b->used * 2 * MP_DIGIT_BIT)) != MP_OKAY) {
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|       return err;
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|    }
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|    return mp_div(a, b, a, NULL);
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| }
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| #endif
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