40 lines
		
	
	
		
			951 B
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			40 lines
		
	
	
		
			951 B
		
	
	
	
		
			C
		
	
	
	
	
	
| #include "tommath_private.h"
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| #ifdef BN_MP_SUBMOD_C
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| /* LibTomMath, multiple-precision integer library -- Tom St Denis
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|  *
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|  * LibTomMath is a library that provides multiple-precision
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|  * integer arithmetic as well as number theoretic functionality.
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|  *
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|  * The library was designed directly after the MPI library by
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|  * Michael Fromberger but has been written from scratch with
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|  * additional optimizations in place.
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|  *
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|  * The library is free for all purposes without any express
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|  * guarantee it works.
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|  */
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| 
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| /* d = a - b (mod c) */
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| int mp_submod(const mp_int *a, const mp_int *b, const mp_int *c, mp_int *d)
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| {
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|    int     res;
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|    mp_int  t;
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| 
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| 
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|    if ((res = mp_init(&t)) != MP_OKAY) {
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|       return res;
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|    }
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| 
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|    if ((res = mp_sub(a, b, &t)) != MP_OKAY) {
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|       mp_clear(&t);
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|       return res;
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|    }
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|    res = mp_mod(&t, c, d);
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|    mp_clear(&t);
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|    return res;
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| }
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| #endif
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| 
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| /* ref:         $Format:%D$ */
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| /* git commit:  $Format:%H$ */
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| /* commit time: $Format:%ai$ */
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