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kynex7510/make_lfcs.py

Created July 28, 2025 19:32
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Build and sign LocalFriendCodeSeed_B files
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make_lfcs.py
"""
make_lfcs.py
Build and sign LocalFriendCodeSeed_B files.
- Kynex7510
"""
from cryptography.hazmat.primitives.asymmetric import rsa, padding
from cryptography.hazmat.primitives import hashes
RETAIL_MODULO = [
0xA3, 0x75, 0x9A, 0x35, 0x46, 0xCF, 0xA7, 0xFE, 0x30, 0xEC, 0x55, 0xA1, 0xB6, 0x4E, 0x08, 0xE9,
0x44, 0x9D, 0x0C, 0x72, 0xFC, 0xD1, 0x91, 0xFD, 0x61, 0x0A, 0x28, 0x89, 0x75, 0xBC, 0xE6, 0xA9,
0xB2, 0x15, 0x56, 0xE9, 0xC7, 0x67, 0x02, 0x55, 0xAD, 0xFC, 0x3C, 0xEE, 0x5E, 0xDB, 0x78, 0x25,
0x9A, 0x4B, 0x22, 0x1B, 0x71, 0xE7, 0xE9, 0x51, 0x5B, 0x2A, 0x67, 0x93, 0xB2, 0x18, 0x68, 0xCE,
0x5E, 0x5E, 0x12, 0xFF, 0xD8, 0x68, 0x06, 0xAF, 0x31, 0x8D, 0x56, 0xF9, 0x54, 0x99, 0x02, 0x34,
0x6A, 0x17, 0xE7, 0x83, 0x74, 0x96, 0xA0, 0x5A, 0xAF, 0x6E, 0xFD, 0xE6, 0xBE, 0xD6, 0x86, 0xAA,
0xFD, 0x7A, 0x65, 0xA8, 0xEB, 0xE1, 0x1C, 0x98, 0x3A, 0x15, 0xC1, 0x7A, 0xB5, 0x40, 0xC2, 0x3D,
0x9B, 0x7C, 0xFD, 0xD4, 0x63, 0xC5, 0xE6, 0xDE, 0xB7, 0x78, 0x24, 0xC6, 0x29, 0x47, 0x33, 0x35,
0xB2, 0xE9, 0x37, 0xE0, 0x54, 0xEE, 0x9F, 0xA5, 0x3D, 0xD7, 0x93, 0xCA, 0x3E, 0xAE, 0x4D, 0xB6,
0x0F, 0x5A, 0x11, 0xE7, 0x0C, 0xDF, 0xBA, 0x03, 0xB2, 0x1E, 0x2B, 0x31, 0xB6, 0x59, 0x06, 0xDB,
0x5F, 0x94, 0x0B, 0xF7, 0x6E, 0x74, 0xCA, 0xD4, 0xAB, 0x55, 0xD9, 0x40, 0x05, 0x8F, 0x10, 0xFE,
0x06, 0x05, 0x0C, 0x81, 0xBB, 0x42, 0x21, 0x90, 0xBA, 0x4F, 0x5C, 0x53, 0x82, 0xE1, 0xE1, 0x0F,
0xBC, 0x94, 0x9F, 0x60, 0x69, 0x5D, 0x13, 0x03, 0xAA, 0xE2, 0xE0, 0xC1, 0x08, 0x42, 0x4C, 0x20,
0x0B, 0x9B, 0xAA, 0x55, 0x2D, 0x55, 0x27, 0x6E, 0x24, 0xE5, 0xD6, 0x04, 0x57, 0x58, 0x8F, 0xF7,
0x5F, 0x0C, 0xEC, 0x81, 0x9F, 0x6D, 0x2D, 0x28, 0xF3, 0x10, 0x55, 0xF8, 0x3B, 0x76, 0x62, 0xD4,
0xE4, 0xA6, 0x93, 0x69, 0xB5, 0xDA, 0x6B, 0x40, 0x23, 0xAF, 0x07, 0xEB, 0x9C, 0xBF, 0xA9, 0xC9
]
DEV_MODULO = [
0x98, 0x59, 0x92, 0xB9, 0x65, 0x17, 0x68, 0xF5, 0xE7, 0x9F, 0x6A, 0xE5, 0x00, 0xCC, 0x57, 0x41,
0x8E, 0x6B, 0x8D, 0xF9, 0xD4, 0x40, 0x9C, 0xEA, 0xFD, 0x96, 0x27, 0xC4, 0x25, 0xD6, 0x16, 0xC2,
0xBC, 0x31, 0xCC, 0x23, 0x20, 0x6B, 0x0A, 0x49, 0x49, 0x31, 0xAA, 0x56, 0x7E, 0x6E, 0xAE, 0x1C,
0x55, 0x06, 0x63, 0xA8, 0x72, 0x1D, 0xEB, 0x16, 0xC5, 0x1E, 0x00, 0x23, 0xE0, 0xBA, 0xBD, 0x26,
0x16, 0x65, 0x19, 0xCE, 0xFE, 0xDB, 0x7F, 0x42, 0x99, 0xCE, 0xE5, 0xCE, 0xCC, 0xB2, 0xC5, 0x18,
0x95, 0x7E, 0x4B, 0xDB, 0xB6, 0x56, 0x7D, 0x7D, 0x73, 0xED, 0x9C, 0xD5, 0x94, 0xCE, 0x26, 0x5D,
0x8B, 0xCA, 0x66, 0x35, 0xCB, 0x60, 0xCA, 0xA3, 0xC1, 0xB6, 0x52, 0x21, 0x2F, 0xF4, 0xFF, 0x45,
0xC7, 0x3B, 0xEB, 0xF4, 0xCD, 0xB6, 0x46, 0x3D, 0x07, 0x61, 0xD6, 0x61, 0xC3, 0x49, 0xAF, 0xBC,
0xF5, 0x5B, 0xAC, 0x71, 0xCD, 0x06, 0x68, 0x46, 0x2F, 0xD1, 0x2E, 0x82, 0xC2, 0x3F, 0xEB, 0x57,
0xCF, 0x62, 0x2E, 0xE7, 0xE2, 0x72, 0x1E, 0x73, 0x70, 0x7A, 0xF4, 0xF7, 0xB0, 0x1B, 0x8A, 0xDF,
0xC2, 0x8D, 0x59, 0xC2, 0xD4, 0x40, 0xCC, 0xF1, 0x41, 0x50, 0xD3, 0x91, 0xA1, 0xF9, 0x5D, 0x9D,
0x45, 0xBC, 0x5A, 0x74, 0x64, 0x1E, 0x22, 0xCE, 0x10, 0xD6, 0x2C, 0xE3, 0x5C, 0x7D, 0xD2, 0xB0,
0xEB, 0xC5, 0x16, 0x64, 0x5C, 0x9A, 0xDC, 0x60, 0x93, 0xA4, 0x4E, 0x75, 0x00, 0xC1, 0xBE, 0x16,
0xE9, 0xD7, 0xD3, 0x5F, 0xB8, 0x69, 0xE6, 0x2C, 0x14, 0x38, 0x51, 0xB3, 0x15, 0x15, 0x57, 0x7F,
0xEA, 0xFE, 0x74, 0x50, 0xE3, 0x6D, 0x60, 0x27, 0xAE, 0x8C, 0x9C, 0xAA, 0xCA, 0xBE, 0x78, 0xEA,
0xE4, 0xA4, 0x8A, 0x65, 0x5B, 0x39, 0x65, 0x0B, 0x7F, 0x0B, 0xDB, 0xC0, 0x73, 0xE0, 0x91, 0xBB
]
def gen_signature(data: bytes, n: int, e: int, d: int) -> bytes:
(p, q) = rsa.rsa_recover_prime_factors(n, e, d)
dmp1 = rsa.rsa_crt_dmp1(d, p)
dmq1 = rsa.rsa_crt_dmq1(d, q)
iqmp = rsa.rsa_crt_iqmp(p, q)
priv_nums = rsa.RSAPrivateNumbers(
p=p,
q=q,
d=d,
dmp1=dmp1,
dmq1=dmq1,
iqmp=iqmp,
public_numbers=rsa.RSAPublicNumbers(e, n))
priv_key = priv_nums.private_key()
return priv_key.sign(data, padding.PKCS1v15(), hashes.SHA256())
if __name__ == "__main__":
rsa_e = 65537
# Ask for key type.
while True:
print("Select key type:")
print("1) Retail")
print("2) Dev")
key_type = int(input("> "))
if key_type >= 1 and key_type <= 2:
break
print("ERROR: Invalid key type")
if key_type == 1:
rsa_n = int.from_bytes(bytes(RETAIL_MODULO), byteorder='big')
else:
rsa_n = int.from_bytes(bytes(DEV_MODULO), byteorder='big')
# Ask for private exponent.
while True:
privexp_path = input("Private exponent file path: ")
try:
with open(privexp_path, "rb") as f:
rsa_d = int.from_bytes(f.read(), byteorder='big')
# Check private exponent.
m = rsa_n//4
c = pow(m, rsa_d, rsa_n)
computed_m = pow(c, rsa_e, rsa_n)
if m == computed_m:
break
print("ERROR: Decryption test failed, invalid private exponent")
except OSError:
print("ERROR: File not found")
# Ask for LFCS.
lfcs = int(input("LFCS (decimal number): "))
# Build file.
lfcsb_data = []
lfcsb_data.extend([0 for _ in range(8)])
if key_type == 2:
lfcsb_data[1] = 0x01
lfcsb_data.extend(lfcs.to_bytes(8, byteorder='little'))
signature = gen_signature(bytes(lfcsb_data), rsa_n, rsa_e, rsa_d)
with open("LocalFriendCodeSeed_B", "wb") as out:
out.write(bytes(signature))
out.write(bytes(lfcsb_data))
print("Done!")
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