python-elmo/elmo/projects/Examples/KyberNTT/poly.c

#include <stdint.h>
#include "params.h"
#include "poly.h"
#include "ntt.h"
#include "reduce.h"

/*************************************************
* Name:        poly_ntt
*
* Description: Computes negacyclic number-theoretic transform (NTT) of
*              a polynomial in place;
*              inputs assumed to be in normal order, output in bitreversed order
*
* Arguments:   - uint16_t *r: pointer to in/output polynomial
**************************************************/
void poly_ntt(poly *r)
{
  ntt(r->coeffs);
  poly_reduce(r);
}

/*************************************************
* Name:        poly_reduce
*
* Description: Applies Barrett reduction to all coefficients of a polynomial
*              for details of the Barrett reduction see comments in reduce.c
*
* Arguments:   - poly *r:       pointer to input/output polynomial
**************************************************/
void poly_reduce(poly *r)
{
  int i;

  for(i=0;i<KYBER_N;i++)
    r->coeffs[i] = barrett_reduce(r->coeffs[i]);
}