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| key_table = [
0x14, 0x18, 0x3D, 0x0C, 0x00, 0x03, 0x32, 0x1F, 0x18, 0x3C,
0x3D, 0x19, 0x2C, 0x42, 0x1B, 0x0F, 0x23, 0x15, 0x0B, 0x1F
]
key_stream_256 = [key_table[i % len(key_table)] for i in range(256)]
S = list(range(256))
j = 0
for i in range(256):
j = (S[i] + j + key_stream_256[i]) & 0xFF
S[i], S[j] = S[j], S[i]
def rc4_prga(state, n):
S = state[:]
i = 0
j = 0
out = []
for _ in range(n):
i = (i + 1) & 0xFF
j = (j + S[i]) & 0xFF
S[i], S[j] = S[j], S[i]
out.append(S[(S[i] + S[j]) & 0xFF])
return out
keystream = rc4_prga(S, 42)
buf1_ints = [
0xBE7D51AF, 0x7EEEE1C6, 0x4FD3C578, 0xB89BFBA1, 0x25B28FEF,
0xAAF725CD, 0xED399B71, 0x8C807901, 0xAE63C11C, 0xEFF75BDF
]
cipher_bytes = []
for value in buf1_ints:
cipher_bytes += [(value >> (8 * k)) & 0xFF for k in range(4)]
v15 = 10008
cipher_bytes += [v15 & 0xFF, (v15 >> 8) & 0xFF]
assert len(cipher_bytes) == 42
plain_bytes = bytes(((c - 113) & 0xFF) ^ k for c, k in zip(cipher_bytes, keystream))
print("Plain (hex):", plain_bytes.hex())
try:
print("Plain (ascii):", plain_bytes.decode('ascii'))
except UnicodeDecodeError:
print("Plain (ascii, replace):", plain_bytes.decode('ascii', errors='replace'))
|
