Read E-KTP image using PN532

ektp_image_reader.py

"""
Author: Faiz J <askmehere@lcat.dev>
Date: 2023-11-01

Another proof of concept of a CompactByte blog article
https://blog.compactbyte.com/2018/06/10/membedah-e-ktp/

To run this script successfully, you must connect a PN532 reader to the USB
port of your computer using a USB-to-TTL converter (I use CH340). Enjoy!
"""

import struct
import sys

import nfc


if len(sys.argv) != 2:
    print(f'usage: {sys.argv[0]} <output.jpg>')
    sys.exit(1)

output_file = sys.argv[1]

clf = nfc.ContactlessFrontend('tty::pn532')

print('waiting for target')
tag = clf.connect(rdwr={'on-connect': lambda tag: False})
print('target detected, sending payloads')

print('selecting DF 7F0A')
resp = tag.transceive(bytearray.fromhex('00 A4 00 00 02 7F 0A'))
assert resp == b'\x90\x00'

print('selecting EF 6FF2')
resp = tag.transceive(bytearray.fromhex('00 A4 00 00 02 6F F2'))
assert resp == b'\x90\x00'

print('getting image size')
resp = tag.transceive(bytearray.fromhex('00 B0 00 00 02'))
size, status = struct.unpack('>HH', resp)
assert status == 0x9000
print(f'image size is {size} bytes')

print('reading image')
img_buf = bytearray()
chunk_size = 0x50
for offset in range(2, size, chunk_size):
    command = bytearray.fromhex('00 B0')
    command += struct.pack('>H', offset)
    command += struct.pack('>B', chunk_size)
    resp = tag.transceive(command)
    chunk, status = struct.unpack(f'>{chunk_size}sH', resp)
    assert status == 0x9000
    img_buf += chunk
    print(f'\rdone reading from offset {offset}', end='')

print(f'\nwriting to {output_file}')
with open(output_file, 'wb') as f:
    f.write(img_buf[:size])
print(f'done!')