commit: af9e72507ea38e5ab3fa2751ed09ec88021260cb
parent 6ca7b776965ed1e9220690edc4ee22de8c8587f5
Author: df <fieldhouse@gmx.net>
Date: Mon, 1 Nov 2021 04:45:42 +0000
Implement n-param descrambling using JSInterp
Fixes #29326, closes #29790, closes #30004, closes #30024, closes #30052,
closes #30088, closes #30097, closes #30102, closes #30109, closes #30119,
closes #30125, closes #30128, closes #30162, closes #30173, closes #30186,
closes #30192, closes #30221, closes #30239, closes #30539, closes #30552.
Diffstat:
1 file changed, 99 insertions(+), 16 deletions(-)
diff --git a/youtube_dl/extractor/youtube.py b/youtube_dl/extractor/youtube.py
@@ -1254,6 +1254,17 @@ class YoutubeIE(YoutubeBaseInfoExtractor):
raise ExtractorError('Cannot identify player %r' % player_url)
return id_m.group('id')
+ def _get_player_code(self, video_id, player_url, player_id=None):
+ if not player_id:
+ player_id = self._extract_player_info(player_url)
+
+ if player_id not in self._code_cache:
+ self._code_cache[player_id] = self._download_webpage(
+ player_url, video_id,
+ note='Downloading player ' + player_id,
+ errnote='Download of %s failed' % player_url)
+ return self._code_cache[player_id]
+
def _extract_signature_function(self, video_id, player_url, example_sig):
player_id = self._extract_player_info(player_url)
@@ -1266,12 +1277,7 @@ class YoutubeIE(YoutubeBaseInfoExtractor):
if cache_spec is not None:
return lambda s: ''.join(s[i] for i in cache_spec)
- if player_id not in self._code_cache:
- self._code_cache[player_id] = self._download_webpage(
- player_url, video_id,
- note='Downloading player ' + player_id,
- errnote='Download of %s failed' % player_url)
- code = self._code_cache[player_id]
+ code = self._get_player_code(video_id, player_url, player_id)
res = self._parse_sig_js(code)
test_string = ''.join(map(compat_chr, range(len(example_sig))))
@@ -1350,11 +1356,6 @@ class YoutubeIE(YoutubeBaseInfoExtractor):
if player_url is None:
raise ExtractorError('Cannot decrypt signature without player_url')
- if player_url.startswith('//'):
- player_url = 'https:' + player_url
- elif not re.match(r'https?://', player_url):
- player_url = compat_urlparse.urljoin(
- 'https://www.youtube.com', player_url)
try:
player_id = (player_url, self._signature_cache_id(s))
if player_id not in self._player_cache:
@@ -1371,6 +1372,88 @@ class YoutubeIE(YoutubeBaseInfoExtractor):
raise ExtractorError(
'Signature extraction failed: ' + tb, cause=e)
+ def _extract_player_url(self, webpage):
+ player_url = self._search_regex(
+ r'"(?:PLAYER_JS_URL|jsUrl)"\s*:\s*"([^"]+)"',
+ webpage or '', 'player URL', fatal=False)
+ if not player_url:
+ return
+ if player_url.startswith('//'):
+ player_url = 'https:' + player_url
+ elif not re.match(r'https?://', player_url):
+ player_url = compat_urlparse.urljoin(
+ 'https://www.youtube.com', player_url)
+ return player_url
+
+ # from yt-dlp
+ # See also:
+ # 1. https://github.com/ytdl-org/youtube-dl/issues/29326#issuecomment-894619419
+ # 2. https://code.videolan.org/videolan/vlc/-/blob/4fb284e5af69aa9ac2100ccbdd3b88debec9987f/share/lua/playlist/youtube.lua#L116
+ # 3. https://github.com/ytdl-org/youtube-dl/issues/30097#issuecomment-950157377
+ def _extract_n_function_name(self, jscode):
+ return self._search_regex(
+ (r'\.get\("n"\)\)&&\(b=(?P<nfunc>[a-zA-Z0-9$]{3})\([a-zA-Z0-9]\)',),
+ jscode, 'Initial JS player n function name', group='nfunc')
+
+ def _extract_n_function(self, video_id, player_url):
+ player_id = self._extract_player_info(player_url)
+ func_code = self._downloader.cache.load('youtube-nsig', player_id)
+
+ if func_code:
+ jsi = JSInterpreter(func_code)
+ else:
+ player_id = self._extract_player_info(player_url)
+ jscode = self._get_player_code(video_id, player_url, player_id)
+ funcname = self._extract_n_function_name(jscode)
+ jsi = JSInterpreter(jscode)
+ func_code = jsi.extract_function_code(funcname)
+ self._downloader.cache.store('youtube-nsig', player_id, func_code)
+
+ if self._downloader.params.get('youtube_print_sig_code'):
+ self.to_screen('Extracted nsig function from {0}:\n{1}\n'.format(player_id, func_code[1]))
+
+ return lambda s: jsi.extract_function_from_code(*func_code)([s])
+
+ def _n_descramble(self, n_param, player_url, video_id):
+ """Compute the response to YT's "n" parameter challenge
+
+ Args:
+ n_param -- challenge string that is the value of the
+ URL's "n" query parameter
+ player_url -- URL of YT player JS
+ video_id
+ """
+
+ sig_id = ('nsig_value', n_param)
+ if sig_id in self._player_cache:
+ return self._player_cache[sig_id]
+
+ try:
+ player_id = ('nsig', player_url)
+ if player_id not in self._player_cache:
+ self._player_cache[player_id] = self._extract_n_function(video_id, player_url)
+ func = self._player_cache[player_id]
+ self._player_cache[sig_id] = func(n_param)
+ if self._downloader.params.get('verbose', False):
+ self._downloader.to_screen('[debug] [%s] %s' % (self.IE_NAME, 'Decrypted nsig {0} => {1}'.format(n_param, self._player_cache[sig_id])))
+ return self._player_cache[sig_id]
+ except Exception as e:
+ raise ExtractorError(traceback.format_exc(), cause=e, video_id=video_id)
+
+ def _unthrottle_format_urls(self, video_id, player_url, formats):
+ for fmt in formats:
+ parsed_fmt_url = compat_urlparse.urlparse(fmt['url'])
+ qs = compat_urlparse.parse_qs(parsed_fmt_url.query)
+ n_param = qs.get('n')
+ if not n_param:
+ continue
+ n_param = n_param[-1]
+ n_response = self._n_descramble(n_param, player_url, video_id)
+ if n_response:
+ qs['n'] = [n_response]
+ fmt['url'] = compat_urlparse.urlunparse(
+ parsed_fmt_url._replace(query=compat_urllib_parse_urlencode(qs, True)))
+
def _mark_watched(self, video_id, player_response):
playback_url = url_or_none(try_get(
player_response,
@@ -1632,11 +1715,7 @@ class YoutubeIE(YoutubeBaseInfoExtractor):
if not (sc and fmt_url and encrypted_sig):
continue
if not player_url:
- if not webpage:
- continue
- player_url = self._search_regex(
- r'"(?:PLAYER_JS_URL|jsUrl)"\s*:\s*"([^"]+)"',
- webpage, 'player URL', fatal=False)
+ player_url = self._extract_player_url(webpage)
if not player_url:
continue
signature = self._decrypt_signature(sc['s'][0], video_id, player_url)
@@ -1782,6 +1861,10 @@ class YoutubeIE(YoutubeBaseInfoExtractor):
is_live = video_details.get('isLive')
owner_profile_url = microformat.get('ownerProfileUrl')
+ if not player_url:
+ player_url = self._extract_player_url(webpage)
+ self._unthrottle_format_urls(video_id, player_url, formats)
+
info = {
'id': video_id,
'title': self._live_title(video_title) if is_live else video_title,