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mirror of https://github.com/trezor/trezor-firmware.git synced 2024-11-15 20:19:23 +00:00
trezor-firmware/tools/build_vendorheader

62 lines
1.6 KiB
Python
Executable File

#!/usr/bin/env python3
import sys
import struct
import binascii
# encode vendor name, add length byte and padding to multiple of 4
def encode_vendor(vname):
vbin = vname.encode()
vbin = struct.pack('<B', len(vbin)) + vbin
vbin += b'\0' * (-len(vbin) & 3)
return vbin
def encode_pubkey(pubkey):
if len(pubkey) != 64:
raise Exception('Wrong public key length')
return binascii.unhexlify(pubkey)
def decode_vtrust(vtrust):
t = 0xFFFF
for i, b in enumerate(reversed(vtrust)):
if b != '.':
t &= ~(1 << i)
return t
def main():
if len(sys.argv) < 7:
print('Usage build_vendorheader "pubkey1hex:pubkey2hex:..." m version vendortrust vendorname vendorimage.toif vendorheader.bin')
return 1
keys = [encode_pubkey(x) for x in sys.argv[1].split(':')]
m = int(sys.argv[2])
(vmajor, vminor) = [int(x) for x in sys.argv[3].split('.')]
vtrust = decode_vtrust(sys.argv[4])
vname = sys.argv[5]
ifn = sys.argv[6]
ofn = sys.argv[7]
if not ifn.endswith('.toif'):
print('Must provide TOIF file')
return 2
expiry = 0
vheader = b'TRZV' + \
struct.pack('<IIBBBBH', 0, expiry, vmajor, vminor, m, len(keys), vtrust)
vheader += 14 * b'\0'
for k in keys:
vheader += k
vheader += encode_vendor(vname) + open(ifn, 'rb').read()
padding = 65 + (-len(vheader) - 65) & 511
vheader += b'\0' * padding
# put in length
vheader = vheader[0:4] + struct.pack('<I', len(vheader)) + vheader[8:]
with open(ofn, 'wb') as f:
f.write(vheader)
main()