kc3-lang/libtommath/bn_mp_to_ubin.c

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• Hash : b6813a41
  Author :
  Date : 2019-09-27T03:40:08
  

  replace mp_export/import by mp_pack/unpack

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• bn_mp_to_ubin.c

• #include "tommath_private.h"
  #ifdef BN_MP_TO_UBIN_C
  /* LibTomMath, multiple-precision integer library -- Tom St Denis */
  /* SPDX-License-Identifier: Unlicense */
  
  /* store in unsigned [big endian] format */
  mp_err mp_to_ubin(const mp_int *a, unsigned char *buf, size_t maxlen, size_t *written)
  {
     size_t    x;
     mp_err  err;
     mp_int  t;
  
     if (maxlen == 0u) {
        return MP_VAL;
     }
  
     if ((err = mp_init_copy(&t, a)) != MP_OKAY) {
        return err;
     }
  
     x = 0u;
     while (!MP_IS_ZERO(&t)) {
        if (maxlen == 0u) {
           err = MP_VAL;
           goto LBL_ERR;
        }
        maxlen--;
  #ifndef MP_8BIT
        buf[x++] = (unsigned char)(t.dp[0] & 255u);
  #else
        buf[x++] = (unsigned char)(t.dp[0] | ((t.dp[1] & 1u) << 7));
  #endif
        if ((err = mp_div_2d(&t, 8, &t, NULL)) != MP_OKAY) {
           goto LBL_ERR;
        }
     }
     s_mp_reverse(buf, x);
  
     if (written != NULL) {
        *written = x;
     }
  LBL_ERR:
     mp_clear(&t);
     return err;
  }
  #endif
  

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