add keybox diff detect

This commit is contained in:
hyugogirubato 2024-11-03 14:03:04 +01:00
parent 57e349acca
commit 6737a9f9ee

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@ -2,6 +2,7 @@ import base64
import json
import logging
from json.encoder import encode_basestring_ascii
from typing import Literal
from uuid import UUID
@ -34,8 +35,8 @@ class Keybox:
Attributes:
logger (Logger): Logger instance for logging messages.
device_id (list[bytes]): List to store unique device IDs (32 bytes each).
keybox (dict[bytes, bytes]): Dictionary to map device IDs to their respective keybox data.
device_id (list[bytes]): List of unique device IDs (32 bytes each).
keybox (dict[bytes, bytes]): Dictionary mapping device IDs to their respective keybox data.
"""
self.logger = logging.getLogger(self.__class__.__name__)
# https://github.com/kaltura/kaltura-device-info-android/blob/master/app/src/main/java/com/kaltura/kalturadeviceinfo/MainActivity.java#L203
@ -57,7 +58,7 @@ class Keybox:
assert size == 32, f'Invalid keybox length: {size}. Should be 32 bytes'
if data not in self.device_id:
self.logger.info('Receive device id: \n\n%s\n', base64.b64encode(data).decode('utf-8'))
self.logger.info('Receive device id: \n\n%s\n', encode_basestring_ascii(data.decode('utf-8')))
self.device_id.append(data)
except Exception as e:
self.logger.debug('Failed to set device id: %s', e)
@ -72,30 +73,33 @@ class Keybox:
Raises:
AssertionError: If the data length is not 128 or 132 bytes or does not meet other criteria.
"""
# https://github.com/wvdumper/dumper/blob/main/Helpers/Keybox.py#L51
# https://github.com/zybpp/Python/tree/master/Python/keybox
try:
size = len(data)
assert size in (128, 132), f'Invalid keybox length: {size}. Should be 128 or 132 bytes'
if size == 132:
assert data[128:132] == b"LVL1", 'QSEE style keybox does not end in bytes "LVL1"'
assert data[128:132] == b"LVL1", 'QSEE-style keybox must end with bytes "LVL1"'
assert data[120:124] == b"kbox", 'Invalid keybox magic'
device_id = data[0:32]
# Retrieve structured keybox info and log it
infos = self.__keybox_info(data)
encrypted = infos['flags'] > 10
self.set_device_id(data=device_id)
# TODO: Detect different keybox (e.g. decrypted)
if device_id not in self.keybox or self.keybox[device_id] != data:
# Fetch keybox info for logging, such as flags and other details
infos = self.__keybox_info(data)
if (device_id in self.keybox and self.keybox[device_id] != (data, encrypted)) or device_id not in self.keybox:
self.logger.info('Receive keybox: \n\n%s\n', json.dumps(infos, indent=2))
# Warn if flags indicate encrypted data, requiring a plain-text device token
if infos['flags'] > 10:
self.logger.warning('Received encrypted data. Plaintext device token interception is required')
# Warn if flags indicate encryption, which requires an unencrypted device token
if encrypted:
self.logger.warning('Keybox contains encrypted data. Interception of plaintext device token is needed')
self.keybox[device_id] = data
# Store or update the keybox for the device if it's not already saved
if (device_id in self.keybox and not encrypted) or device_id not in self.keybox:
self.keybox[device_id] = (data, encrypted)
except Exception as e:
self.logger.debug('Failed to set keybox: %s', e)
@ -111,25 +115,24 @@ class Keybox:
dict: A dictionary containing extracted keybox information.
"""
# https://github.com/wvdumper/dumper/blob/main/Helpers/Keybox.py#L51
# Extract key components from the keybox data based on defined byte offsets.
device_token = data[48:120]
content = {
'device_id': data[0:32], # Unique identifier for the device (32 bytes).
'device_key': data[32:48], # Device-specific cryptographic key (16 bytes).
'device_token': data[48:120], # AES key used for device token encryption (72 bytes).
'keybox_tag': data[120:124].decode('utf-8'), # Magic tag indicating keybox format (4 bytes).
'crc32': bytes2int(data[124:128]), # CRC32 checksum for data integrity verification (4 bytes).
'device_id': data[0:32].decode('utf-8'), # Device's unique identifier (32 bytes)
'device_key': data[32:48], # Device-specific cryptographic key (16 bytes)
'device_token': device_token, # Token used for device authentication (72 bytes)
'keybox_tag': data[120:124].decode('utf-8'), # Magic tag indicating keybox format (4 bytes)
'crc32': bytes2int(data[124:128]), # CRC32 checksum for data integrity verification (4 bytes)
'level_tag': data[128:132].decode('utf-8') or None, # Optional tag indicating keybox level (4 bytes).
# TODO: decrypt device_token field
# Key components extracted from the device token (Bytes 48119).
'flags': bytes2int(data[48:52]), # Flags indicating various settings (4 bytes).
'system_id': bytes2int(data[52:56]), # System identifier for the device (4 bytes).
# Additional metadata parsed from the device token (Bytes 48120).
'flags': bytes2int(device_token[0:4]), # Flags indicating specific device capabilities (4 bytes).
'system_id': bytes2int(device_token[4:8]), # System identifier (4 bytes).
# Provisioning ID, encrypted and derived from the unique ID in the system.
'provisioning_id': UUID(bytes_le=data[56:72]), # Unique ID for provisioning (16 bytes).
'provisioning_id': UUID(bytes_le=device_token[8:24]), # Provisioning UUID (16 bytes).
# Encrypted bits containing device key, key hash, and additional flags.
'encrypted_bits': data[72:120] # Encrypted data relevant to the device (48 bytes).
'encrypted_bits': device_token[24:72] ## Encrypted device-specific information (48 bytes).
}
# Encode certain fields in base64 and convert UUIDs to string
@ -150,11 +153,15 @@ class Keybox:
"""
keys = self.device_id & self.keybox.keys()
for k in keys:
# Prepare target directory and export file path
parent.mkdir(parents=True, exist_ok=True)
path_keybox_bin = parent / 'keybox.bin'
path_keybox_bin.write_bytes(self.keybox[k])
path_keybox_bin = parent / f"keybox.{'enc' if self.keybox[k][1] else 'bin'}"
path_keybox_bin.write_bytes(self.keybox[k][0])
self.logger.info('Exported Keybox: %s', path_keybox_bin)
if self.keybox[k][1]:
self.logger.warning('Exported encrypted keybox: %s', path_keybox_bin)
else:
self.logger.info('Exported keybox: %s', path_keybox_bin)
return len(keys) > 0