deemix-py/deemix/decryption.py

141 lines
5.8 KiB
Python

import binascii
from ssl import SSLError
from time import sleep
import logging
from Cryptodome.Cipher import Blowfish, AES
from Cryptodome.Hash import MD5
from requests import get
from requests.exceptions import ConnectionError as RequestsConnectionError, ReadTimeout
from urllib3.exceptions import SSLError as u3SSLError
from deemix import USER_AGENT_HEADER
from deemix.types.DownloadObjects import Single
logger = logging.getLogger('deemix')
def _md5(data):
h = MD5.new()
h.update(data.encode() if isinstance(data, str) else data)
return h.hexdigest()
def generateBlowfishKey(trackId):
SECRET = 'g4el58wc0zvf9na1'
idMd5 = _md5(trackId)
bfKey = ""
for i in range(16):
bfKey += chr(ord(idMd5[i]) ^ ord(idMd5[i + 16]) ^ ord(SECRET[i]))
return bfKey
def generateStreamPath(sng_id, md5, media_version, media_format):
urlPart = b'\xa4'.join(
[md5.encode(), str(media_format).encode(), str(sng_id).encode(), str(media_version).encode()])
md5val = _md5(urlPart)
step2 = md5val.encode() + b'\xa4' + urlPart + b'\xa4'
step2 = step2 + (b'.' * (16 - (len(step2) % 16)))
urlPart = binascii.hexlify(AES.new(b'jo6aey6haid2Teih', AES.MODE_ECB).encrypt(step2))
return urlPart.decode("utf-8")
def reverseStreamPath(urlPart):
step2 = AES.new(b'jo6aey6haid2Teih', AES.MODE_ECB).decrypt(binascii.unhexlify(urlPart.encode("utf-8")))
(_, md5, media_format, sng_id, media_version, _) = step2.split(b'\xa4')
return (sng_id.decode('utf-8'), md5.decode('utf-8'), media_version.decode('utf-8'), media_format.decode('utf-8'))
def generateStreamURL(sng_id, md5, media_version, media_format):
urlPart = generateStreamPath(sng_id, md5, media_version, media_format)
return "https://e-cdns-proxy-" + md5[0] + ".dzcdn.net/mobile/1/" + urlPart
def generateUnencryptedStreamURL(sng_id, md5, media_version, media_format):
urlPart = generateStreamPath(sng_id, md5, media_version, media_format)
return "https://e-cdns-proxy-" + md5[0] + ".dzcdn.net/api/1/" + urlPart
def reverseStreamURL(url):
urlPart = url[url.find("/1/")+3:]
return reverseStreamPath(urlPart)
def streamUnencryptedTrack(outputStream, track, start=0, downloadObject=None, interface=None):
headers= {'User-Agent': USER_AGENT_HEADER}
chunkLength = start
itemName = f"[{track.mainArtist.name} - {track.title}]"
try:
with get(track.downloadUrl, headers=headers, stream=True, timeout=10) as request:
request.raise_for_status()
complete = int(request.headers["Content-Length"])
if complete == 0: raise DownloadEmpty
if start != 0:
responseRange = request.headers["Content-Range"]
logger.info('%s downloading range %s', itemName, responseRange)
else:
logger.info('%s downloading %s bytes', itemName, complete)
for chunk in request.iter_content(2048 * 3):
outputStream.write(chunk)
chunkLength += len(chunk)
if downloadObject:
if isinstance(downloadObject, Single):
percentage = (chunkLength / (complete + start)) * 100
downloadObject.progressNext = percentage
else:
chunkProgres = (len(chunk) / (complete + start)) / downloadObject.size * 100
downloadObject.progressNext += chunkProgres
downloadObject.updateProgress(interface)
except (SSLError, u3SSLError):
logger.info('%s retrying from byte %s', itemName, chunkLength)
streamUnencryptedTrack(outputStream, track, chunkLength, downloadObject, interface)
except (RequestsConnectionError, ReadTimeout):
sleep(2)
streamUnencryptedTrack(outputStream, track, start, downloadObject, interface)
def streamTrack(outputStream, track, start=0, downloadObject=None, interface=None):
headers= {'User-Agent': USER_AGENT_HEADER}
chunkLength = start
percentage = 0
itemName = f"[{track.mainArtist.name} - {track.title}]"
try:
with get(track.downloadUrl, headers=headers, stream=True, timeout=10) as request:
request.raise_for_status()
blowfish_key = str.encode(generateBlowfishKey(str(track.id)))
complete = int(request.headers["Content-Length"])
if complete == 0: raise DownloadEmpty
if start != 0:
responseRange = request.headers["Content-Range"]
logger.info('%s downloading range %s', itemName, responseRange)
else:
logger.info('%s downloading %s bytes', itemName, complete)
for chunk in request.iter_content(2048 * 3):
if len(chunk) >= 2048:
chunk = Blowfish.new(blowfish_key, Blowfish.MODE_CBC, b"\x00\x01\x02\x03\x04\x05\x06\x07").decrypt(chunk[0:2048]) + chunk[2048:]
outputStream.write(chunk)
chunkLength += len(chunk)
if downloadObject:
if isinstance(downloadObject, Single):
percentage = (chunkLength / (complete + start)) * 100
downloadObject.progressNext = percentage
else:
chunkProgres = (len(chunk) / (complete + start)) / downloadObject.size * 100
downloadObject.progressNext += chunkProgres
downloadObject.updateProgress(interface)
except (SSLError, u3SSLError):
logger.info('%s retrying from byte %s', itemName, chunkLength)
streamTrack(outputStream, track, chunkLength, downloadObject, interface)
except (RequestsConnectionError, ReadTimeout):
sleep(2)
streamTrack(outputStream, track, start, downloadObject, interface)
class DownloadEmpty(Exception):
pass