[letv] Fix extraction

Using data URIs for passing the decrypted M3U8 manifest, which is
supported by ffmpeg only.

youtube_dl/extractor/letv.py

@@ -9,13 +9,14 @@
 from ..compat import (
     compat_urllib_parse,
     compat_urllib_request,
-    compat_urlparse,
+    compat_ord,
 )
 from ..utils import (
     determine_ext,
     ExtractorError,
     parse_iso8601,
     int_or_none,
+    encode_data_uri,
 )
 
 
@@ -25,15 +26,16 @@ class LetvIE(InfoExtractor):
 
     _TESTS = [{
         'url': 'http://www.letv.com/ptv/vplay/22005890.html',
-        'md5': 'cab23bd68d5a8db9be31c9a222c1e8df',
+        'md5': 'edadcfe5406976f42f9f266057ee5e40',
         'info_dict': {
             'id': '22005890',
             'ext': 'mp4',
             'title': '第87届奥斯卡颁奖礼完美落幕 《鸟人》成最大赢家',
-            'timestamp': 1424747397,
-            'upload_date': '20150224',
             'description': 'md5:a9cb175fd753e2962176b7beca21a47c',
-        }
+        },
+        'params': {
+            'hls_prefer_native': True,
+        },
     }, {
         'url': 'http://www.letv.com/ptv/vplay/1415246.html',
         'info_dict': {
@@ -42,16 +44,22 @@ class LetvIE(InfoExtractor):
             'title': '美人天下01',
             'description': 'md5:f88573d9d7225ada1359eaf0dbf8bcda',
         },
+        'params': {
+            'hls_prefer_native': True,
+        },
     }, {
         'note': 'This video is available only in Mainland China, thus a proxy is needed',
         'url': 'http://www.letv.com/ptv/vplay/1118082.html',
-        'md5': 'f80936fbe20fb2f58648e81386ff7927',
+        'md5': '2424c74948a62e5f31988438979c5ad1',
         'info_dict': {
             'id': '1118082',
             'ext': 'mp4',
             'title': '与龙共舞 完整版',
             'description': 'md5:7506a5eeb1722bb9d4068f85024e3986',
         },
+        'params': {
+            'hls_prefer_native': True,
+        },
         'skip': 'Only available in China',
     }]
 
@@ -74,6 +82,27 @@ def calc_time_key(self, param1):
         _loc3_ = self.ror(_loc3_, _loc2_ % 17)
         return _loc3_
 
+    # see M3U8Encryption class in KLetvPlayer.swf
+    @staticmethod
+    def decrypt_m3u8(encrypted_data):
+        if encrypted_data[:5].decode('utf-8').lower() != 'vc_01':
+            return encrypted_data
+        encrypted_data = encrypted_data[5:]
+
+        _loc4_ = bytearray()
+        while encrypted_data:
+            b = compat_ord(encrypted_data[0])
+            _loc4_.extend([b // 16, b & 0x0f])
+            encrypted_data = encrypted_data[1:]
+        idx = len(_loc4_) - 11
+        _loc4_ = _loc4_[idx:] + _loc4_[:idx]
+        _loc7_ = bytearray()
+        while _loc4_:
+            _loc7_.append(_loc4_[0] * 16 + _loc4_[1])
+            _loc4_ = _loc4_[2:]
+
+        return bytes(_loc7_)
+
     def _real_extract(self, url):
         media_id = self._match_id(url)
         page = self._download_webpage(url, media_id)
@@ -115,23 +144,28 @@ def _real_extract(self, url):
         for format_id in formats:
             if format_id in dispatch:
                 media_url = playurl['domain'][0] + dispatch[format_id][0]
-
-                # Mimic what flvxz.com do
-                url_parts = list(compat_urlparse.urlparse(media_url))
-                qs = dict(compat_urlparse.parse_qs(url_parts[4]))
-                qs.update({
-                    'platid': '14',
-                    'splatid': '1401',
-                    'tss': 'no',
-                    'retry': 1
+                media_url += '&' + compat_urllib_parse.urlencode({
+                    'm3v': 1,
+                    'format': 1,
+                    'expect': 3,
+                    'rateid': format_id,
                 })
-                url_parts[4] = compat_urllib_parse.urlencode(qs)
-                media_url = compat_urlparse.urlunparse(url_parts)
+
+                nodes_data = self._download_json(
+                    media_url, media_id,
+                    'Download JSON metadata for format %s' % format_id)
+
+                req = self._request_webpage(
+                    nodes_data['nodelist'][0]['location'], media_id,
+                    note='Downloading m3u8 information for format %s' % format_id)
+
+                m3u8_data = self.decrypt_m3u8(req.read())
 
                 url_info_dict = {
-                    'url': media_url,
+                    'url': encode_data_uri(m3u8_data, 'application/x-mpegURL'),
                     'ext': determine_ext(dispatch[format_id][1]),
                     'format_id': format_id,
+                    'protocol': 'm3u8',
                 }
 
                 if format_id[-1:] == 'p':

youtube_dl/utils.py

@@ -3,6 +3,7 @@
 
 from __future__ import unicode_literals
 
+import base64
 import calendar
 import codecs
 import contextlib
@@ -1795,6 +1796,10 @@ def urlhandle_detect_ext(url_handle):
     return mimetype2ext(getheader('Content-Type'))
 
 
+def encode_data_uri(data, mime_type):
+    return 'data:%s;base64,%s' % (mime_type, base64.b64encode(data).decode('ascii'))
+
+
 def age_restricted(content_limit, age_limit):
     """ Returns True iff the content should be blocked """