Method Details

• reduce

  byte[] reduce(byte[] s)

  Reduce the given scalar mod $l$.

  From the Ed25519 paper:
  Here we interpret $2b$-bit strings in little-endian form as integers in $\{0, 1,..., 2^{(2b)}-1\}$.

  Parameters:

  s - the scalar to reduce

  Returns:

  $s \bmod l$

• multiplyAndAdd

  byte[] multiplyAndAdd(byte[] a, byte[] b, byte[] c)

  $r = (a * b + c) \bmod l$.

  Parameters:

  a - the first multiplicand, a scalar in little-endian form

  b - the second multiplicand, a scalar in little-endian form

  c - the addend, a scalar in little-endian form

  Returns:

  $(a*b + c) \bmod l$