naive.sage 2.8 KB

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  1. q = 0x40000000000000000000000000000000224698fc0994a8dd8c46eb2100000001
  2. K = GF(q)
  3. a = K(0x00)
  4. b = K(0x05)
  5. E = EllipticCurve(K, (a, b))
  6. G = E(0x40000000000000000000000000000000224698fc0994a8dd8c46eb2100000000, 0x02)
  7. p = 0x40000000000000000000000000000000224698fc094cf91b992d30ed00000001
  8. assert E.order() == p
  9. Scalar = GF(p)
  10. a1, a2, a3, a4, a5, a6, a7, a8, a9, a10 = (
  11. Scalar(110), Scalar(56), Scalar(89), Scalar(6543), Scalar(2),
  12. Scalar(110), Scalar(44), Scalar(78), Scalar(77), Scalar(4))
  13. G1, G2, G3, G4, G5, G6, G7, G8, G9, G10 = (
  14. E.random_element(), E.random_element(), E.random_element(),
  15. E.random_element(), E.random_element(), E.random_element(),
  16. E.random_element(), E.random_element(), E.random_element(),
  17. E.random_element())
  18. A = (int(a1) * G1 + int(a2) * G2 + int(a3) * G3 + int(a4) * G4
  19. + int(a5) * G5 + int(a6) * G6 + int(a7) * G7 + int(a8) * G8
  20. + int(a9) * G9 + int(a10) * G10)
  21. a1, a2, a3, a4, a5 = (a1, a2), (a3, a4), (a5, a6), (a7, a8), (a9, a10)
  22. G1, G2, G3, G4, G5 = (G1, G2), (G3, G4), (G5, G6), (G7, G8), (G9, G10)
  23. # a1 G1-\ a2 G1 a3 G1 a4 G1 a5 G1
  24. # a1 G2 \-a2 G2-\ a3 G2 a4 G2 a5 G2
  25. # a1 G3 a2 G3 \-a3 G3-\ a4 G3 a5 G3
  26. # a1 G4 a2 G4 a3 G4 \-a4 G4-\ a5 G4
  27. # a1 G5 a2 G5 a3 G5 a4 G5 \-a5 G5
  28. # Dot product
  29. def dot(x, y):
  30. result = None
  31. for x_i, y_i in zip(x, y):
  32. if result is None:
  33. result = int(x_i) * y_i
  34. else:
  35. result += int(x_i) * y_i
  36. return result
  37. # Main diagonal is sum(a_i G_i) = A
  38. assert dot(a1, G1) + dot(a2, G2) + dot(a3, G3) + dot(a4, G4) + dot(a5, G5) == A
  39. # Sum all the diagonals of the grid above
  40. A_neg_4 = dot(a1, G5)
  41. A_neg_3 = dot(a1, G4) + dot(a2, G5)
  42. A_neg_2 = dot(a1, G3) + dot(a2, G4) + dot(a3, G5)
  43. A_neg_1 = dot(a1, G2) + dot(a2, G3) + dot(a3, G4) + dot(a4, G5)
  44. A_0 = A
  45. A_1 = dot(a2, G1) + dot(a3, G2) + dot(a4, G3) + dot(a5, G4)
  46. A_2 = dot(a3, G1) + dot(a4, G2) + dot(a5, G3)
  47. A_3 = dot(a4, G1) + dot(a5, G2)
  48. A_4 = dot(a5, G1)
  49. x = Scalar.random_element()
  50. a_prime = (x * vector(a1) + x^2 * vector(a2)
  51. + x^3 * vector(a3) + x^4 * vector(a4)
  52. + x^5 * vector(a5))
  53. # Sage cannot do this:
  54. #
  55. # G_prime = (int(x^-1) * vector(G1) + int(x^-2) * vector(G2)
  56. # + int(x^-3) * vector(G3) + int(x^-4) * vector(G4)
  57. # + int(x^-5) * vector(G5))
  58. G_prime = [(int(x^-1) * G1[0] + int(x^-2) * G2[0] + int(x^-3) * G3[0]
  59. + int(x^-4) * G4[0] + int(x^-5) * G5[0]),
  60. (int(x^-1) * G1[1] + int(x^-2) * G2[1] + int(x^-3) * G3[1]
  61. + int(x^-4) * G4[1] + int(x^-5) * G5[1])]
  62. assert len(a_prime) == len(G_prime) == 2
  63. A_prime = dot(a_prime, G_prime)
  64. assert (int(x^-4) * A_neg_4 + int(x^-3) * A_neg_3 + int(x^-2) * A_neg_2
  65. + int(x^-1) * A_neg_1
  66. + A
  67. + int(x) * A_1 + int(x^2) * A_2 + int(x^3) * A_3 + int(x^4) * A_4) \
  68. == A_prime