@@ -67,55 +67,3 @@ def process_block(block: bytes, *, rounds=12) -> bytes:
6767 data += b"\x01 "
6868 with open ("random.bin.reimpl" , "wb" ) as fp :
6969 fp .write (process_block (data , rounds = 12 ))
70- 71- def solve_derive (solve_for , m ):
72- 73- R .< x > = PolynomialRing (GF (2 ))
74- irreducible_poly = x ^ 16 + x ^ 5 + x ^ 3 + x + 1
75- F = GF (2 ^ 16 , modulus = irreducible_poly , name = 'a' )
76- 77- F_solve_for = [F .from_integer (x ) for x in solve_for ]
78- 79- G .< a0 , a1 , a2 , a3 , a4 , a5 > = F []
80- if m == 0 :
81- my_id = Ideal (
82- a0 * a1 + a4 - F_solve_for [0 ],
83- a1 * a2 + a5 - F_solve_for [1 ],
84- a2 * a3 + a0 - F_solve_for [2 ],
85- a3 * a4 + a1 - F_solve_for [3 ],
86- a4 * a5 + a2 - F_solve_for [4 ],
87- a5 * a0 + a3 - F_solve_for [5 ],
88- )
89- elif m == 1 :
90- my_id = Ideal (
91- a2 * a3 + a5 - F_solve_for [0 ],
92- a3 * a4 + a0 - F_solve_for [1 ],
93- a4 * a5 + a1 - F_solve_for [2 ],
94- a5 * a0 + a2 - F_solve_for [3 ],
95- a0 * a1 + a3 - F_solve_for [4 ],
96- a1 * a2 + a4 - F_solve_for [5 ],
97- )
98- assert my_id .dimension () == 0
99- my_variety = my_id .variety ()
100- fuckshit = [[
101- variety [a0 ].integer_representation (),
102- variety [a1 ].integer_representation (),
103- variety [a2 ].integer_representation (),
104- variety [a3 ].integer_representation (),
105- variety [a4 ].integer_representation (),
106- variety [a5 ].integer_representation ()
107- ] for variety in my_variety ]
108- return fuckshit
109- 110- possible_solution = solve_derive ([u16 (rv1 [i * 2 : i * 2 + 2 ], m = 1 ) for i in range (6 )])
111- possible_solution = [b"" .join (p16 (x ) for x in possible_solution )]
112- possible_rv0s = [derive (x , m = 0 ) for x in possible_solution ]
113- 114- b2 , cb1 , bs , cb2 , rv1 = data [:12 ],data [12 :24 ],data [24 :36 ],data [36 :48 ],data [48 :60 ]
115- b1 = xor (hashlib .sha1 (rv1 + b2 ).digest ()[:12 ], cb2 )
116- b0 = xor (hashlib .md5 (rv0 + b2 ).digest ()[:12 ], cb1 )
117- i = [int .from_bytes (x , "little" ) for x in [b0 ,b1 ,b2 ]]
118- i3 = ((((bs - pow (i [2 ], i [1 ], P ) % P ) * pow (i [0 ],- 1 ,P )) % P ) - i [1 ]) % P
119- b3 = i3 .to_bytes (12 ,'little' )
120- b = b0 + b1 + b2 + b3
121- print (b .hex ())
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