deemix-py/deemix/decryption.py
2021-10-07 14:57:09 +02:00

112 lines
4.6 KiB
Python

from ssl import SSLError
from time import sleep
import logging
from requests import get
from requests.exceptions import ConnectionError as RequestsConnectionError, ReadTimeout, ChunkedEncodingError
from urllib3.exceptions import SSLError as u3SSLError
from deemix.utils.crypto import _md5, _ecbCrypt, _ecbDecrypt, generateBlowfishKey, decryptChunk
from deemix.utils import USER_AGENT_HEADER
from deemix.types.DownloadObjects import Single
from deemix.errors import DownloadCanceled, DownloadEmpty
logger = logging.getLogger('deemix')
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 = _ecbCrypt('jo6aey6haid2Teih', step2)
return urlPart.decode("utf-8")
def reverseStreamPath(urlPart):
step2 = _ecbDecrypt('jo6aey6haid2Teih', urlPart)
(_, 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 generateCryptedStreamURL(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 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/api/1/" + urlPart
def reverseStreamURL(url):
urlPart = url[url.find("/1/")+3:]
return reverseStreamPath(urlPart)
def streamTrack(outputStream, track, start=0, downloadObject=None, listener=None):
if downloadObject and downloadObject.isCanceled: raise DownloadCanceled
headers= {'User-Agent': USER_AGENT_HEADER}
chunkLength = start
isCryptedStream = "/mobile/" in track.downloadURL or "/media/" in track.downloadURL
itemData = {
'id': track.id,
'title': track.title,
'artist': track.mainArtist.name
}
try:
with get(track.downloadURL, headers=headers, stream=True, timeout=10) as request:
request.raise_for_status()
if isCryptedStream:
blowfish_key = generateBlowfishKey(str(track.id))
complete = int(request.headers["Content-Length"])
if complete == 0: raise DownloadEmpty
if start != 0:
responseRange = request.headers["Content-Range"]
if listener:
listener.send('downloadInfo', {
'uuid': downloadObject.uuid,
'data': itemData,
'state': "downloading",
'alreadyStarted': True,
'value': responseRange
})
else:
if listener:
listener.send('downloadInfo', {
'uuid': downloadObject.uuid,
'data': itemData,
'state': "downloading",
'alreadyStarted': False,
'value': complete
})
isStart = True
for chunk in request.iter_content(2048 * 3):
if isCryptedStream:
if len(chunk) >= 2048:
chunk = decryptChunk(blowfish_key, chunk[0:2048]) + chunk[2048:]
if isStart and chunk[0] == 0:
for i, byte in enumerate(chunk):
if byte != 0: break
chunk = chunk[i:]
isStart = False
outputStream.write(chunk)
chunkLength += len(chunk)
if downloadObject:
if isinstance(downloadObject, Single):
chunkProgres = (chunkLength / (complete + start)) * 100
downloadObject.progressNext = chunkProgres
else:
chunkProgres = (len(chunk) / (complete + start)) / downloadObject.size * 100
downloadObject.progressNext += chunkProgres
downloadObject.updateProgress(listener)
except (SSLError, u3SSLError):
streamTrack(outputStream, track, chunkLength, downloadObject, listener)
except (RequestsConnectionError, ReadTimeout, ChunkedEncodingError):
sleep(2)
streamTrack(outputStream, track, start, downloadObject, listener)