LeakLWE2/Sec6_applications/exploiting_design_ntru.sage

#!/usr/bin/sage -python
# -*- coding: latin-1 -*-

load("../framework/instance_gen.sage")

verbosity = 0
report_every = None

"""  Example
Uncomment the following to get the detailed computation
"""
# verbosity = 2
# report_every = 20

for params in [ 'ntruhps2048509', 'ntruhps2048677', 'ntruhps4096821']:

  logging("Set of parameters: " + params)
  if params == 'ntruhps2048509':
    n = 509
    m = 509
    q = 2048

  elif params == 'ntruhps2048677':
    n = 677
    m = 677
    q = 2048

  elif params == 'ntruhps4096821':
    n = 821
    m = 821
    q = 4096

  hamming_weight = (q / 16 - 1)

  if q / 8 - 2 <= 2 * n / 3:
      hamming_weight = (q / 16 - 1)
  else:
      hamming_weight = floor(n / 3)
  D_s = {- 1: RR(hamming_weight / n),
         0: 1 - RR(2 * hamming_weight / n),
         1: RR(hamming_weight / n)}
  # D_e = {- 1: RR(hamming_weight / n),
  #        0: 1 - RR(2 * hamming_weight / n),
  #        1: RR(hamming_weight / n)}
  D_e = {-1: RR(1 / 3), 0: RR(1 / 3), 1: RR(1 / 3)}



  # Assessement of the attack without hints
 
  A, b, dbdd = initialize_NTRU_instance(DBDD_predict_diag,
                                        n, q, m, D_e, D_s,
                                        verbosity=verbosity)
  if report_every is not None:
    dbdd.integrate_q_vectors(q, indices=range(0, n + m), report_every=report_every)
  else:
    dbdd.integrate_q_vectors(q, indices=range(0, n + m))
  (beta, _) = dbdd.estimate_attack()
  logging("Attack without hints:  %3.2f bikz" % beta, style="HEADER")

  # Assessement of the attack with hints

  A, b, dbdd = initialize_NTRU_instance(DBDD_predict,
                                        n, q, m, D_e, D_s,
                                        verbosity=verbosity)

  v = vec([0 if i < m else 1 for i in range(m + n)])
  dbdd.integrate_perfect_hint(v, 0)

  if report_every is not None:
    dbdd.integrate_q_vectors(q, indices=range(0, m), report_every=report_every)
  else:
    dbdd.integrate_q_vectors(q, indices=range(0, m))
  (beta, _) = dbdd.estimate_attack()
  logging("Attack without hints:  %3.2f bikz" % beta, style="HEADER")