The new updates system, relies on gh-pages, secured by RSA, uses external web servers

2 files changed, 112 insertions, 49 deletions

diff --git a/youtube_dl/__init__.py b/youtube_dl/__init__.py
index d12ece21e..cc2f555b9 100644
--- a/youtube_dl/__init__.py
+++ b/youtube_dl/__init__.py
@@ -41,47 +41,90 @@ from .FileDownloader import *
 from .InfoExtractors import *
 from .PostProcessor import *
 
-def updateSelf(downloader, filename):
+def update_self(to_screen, verbose, filename):
     """Update the program file with the latest version from the repository"""
 
-    # TODO: at least, check https certificates
-
     from zipimport import zipimporter
+    import json, traceback, hashlib
 
-    API_URL = "https://api.github.com/repos/rg3/youtube-dl/downloads"
-    BIN_URL = "https://github.com/downloads/rg3/youtube-dl/youtube-dl"
-    EXE_URL = "https://github.com/downloads/rg3/youtube-dl/youtube-dl.exe"
+    UPDATE_URL = "http://rg3.github.com/youtube-dl/update/"
+    VERSION_URL = UPDATE_URL + 'LATEST_VERSION'
+    JSON_URL = UPDATE_URL + 'versions.json'
+    UPDATES_RSA_KEY = (0x9d60ee4d8f805312fdb15a62f87b95bd66177b91df176765d13514a0f1754bcd2057295c5b6f1d35daa6742c3ffc9a82d3e118861c207995a8031e151d863c9927e304576bc80692bc8e094896fcf11b66f3e29e04e3a71e9a11558558acea1840aec37fc396fb6b65dc81a1c4144e03bd1c011de62e3f1357b327d08426fe93, 65537)
 
-    if hasattr(sys, "frozen"): # PY2EXE
-        if not os.access(filename, os.W_OK):
-            sys.exit('ERROR: no write permissions on %s' % filename)
 
-        downloader.to_screen(u'Updating to latest version...')
+    if not isinstance(globals().get('__loader__'), zipimporter) and not hasattr(sys, "frozen"):
+        to_screen(u'It looks like you installed youtube-dl with pip, setup.py or a tarball. Please use that to update.')
+        return
 
-        urla = compat_urllib_request.urlopen(API_URL)
-        download = filter(lambda x: x["name"] == "youtube-dl.exe", json.loads(urla.read()))
-        if not download:
-            downloader.to_screen(u'ERROR: can\'t find the current version. Please try again later.')
-            return
-        newversion = download[0]["description"].strip()
-        if newversion == __version__:
-            downloader.to_screen(u'youtube-dl is up-to-date (' + __version__ + ')')
-            return
-        urla.close()
+    # Check if there is a new version
+    try:
+        newversion = compat_urllib_request.urlopen(VERSION_URL).read().decode('utf-8').strip()
+    except:
+        if verbose: to_screen(traceback.format_exc().decode())
+        to_screen(u'ERROR: can\'t find the current version. Please try again later.')
+        return
+    if newversion == __version__:
+        to_screen(u'youtube-dl is up-to-date (' + __version__ + ')')
+        return
 
+    # Download and check versions info
+    try:
+        versions_info = compat_urllib_request.urlopen(JSON_URL).read().decode('utf-8')
+        versions_info = json.loads(versions_info)
+    except:
+        if verbose: to_screen(traceback.format_exc().decode())
+        to_screen(u'ERROR: can\'t obtain versions info. Please try again later.')
+        return
+    if not 'signature' in versions_info:
+        to_screen(u'ERROR: the versions file is not signed or corrupted. Aborting.')
+        return
+    signature = versions_info['signature']
+    del versions_info['signature']
+    if not rsa_verify(json.dumps(versions_info, sort_keys=True), signature, UPDATES_RSA_KEY):
+        to_screen(u'ERROR: the versions file signature is invalid. Aborting.')
+        return
+
+    to_screen(u'Updating to version ' + versions_info['latest'] + '...')
+    version = versions_info['versions'][versions_info['latest']]
+    if version.get('notes'):
+        to_screen(u'PLEASE NOTE:')
+        for note in version['notes']:
+            to_screen(note)
+
+    if not os.access(filename, os.W_OK):
+        to_screen(u'ERROR: no write permissions on %s' % filename)
+        return
+
+    # Py2EXE
+    if hasattr(sys, "frozen"):
         exe = os.path.abspath(filename)
         directory = os.path.dirname(exe)
         if not os.access(directory, os.W_OK):
-            sys.exit('ERROR: no write permissions on %s' % directory)
+            to_screen(u'ERROR: no write permissions on %s' % directory)
+            return
 
         try:
-            urlh = compat_urllib_request.urlopen(EXE_URL)
+            urlh = compat_urllib_request.urlopen(version['exe'][0])
             newcontent = urlh.read()
             urlh.close()
+        except (IOError, OSError) as err:
+            if verbose: to_screen(traceback.format_exc().decode())
+            to_screen(u'ERROR: unable to download latest version')
+            return
+
+        newcontent_hash = hashlib.sha256(newcontent).hexdigest()
+        if newcontent_hash != version['exe'][1]:
+            to_screen(u'ERROR: the downloaded file hash does not match. Aborting.')
+            return
+
+        try:
             with open(exe + '.new', 'wb') as outf:
                 outf.write(newcontent)
         except (IOError, OSError) as err:
-            sys.exit('ERROR: unable to download latest version')
+            if verbose: to_screen(traceback.format_exc().decode())
+            to_screen(u'ERROR: unable to write the new version')
+            return
 
         try:
             bat = os.path.join(directory, 'youtube-dl-updater.bat')
@@ -96,43 +139,35 @@ del "%s"
 
             os.startfile(bat)
         except (IOError, OSError) as err:
-            sys.exit('ERROR: unable to overwrite current version')
-
-    elif isinstance(globals().get('__loader__'), zipimporter): # UNIX ZIP
-        if not os.access(filename, os.W_OK):
-            sys.exit('ERROR: no write permissions on %s' % filename)
-
-        downloader.to_screen(u'Updating to latest version...')
-
-        urla = compat_urllib_request.urlopen(API_URL)
-        download = [x for x in json.loads(urla.read().decode('utf8')) if x["name"] == "youtube-dl"]
-        if not download:
-            downloader.to_screen(u'ERROR: can\'t find the current version. Please try again later.')
+            if verbose: to_screen(traceback.format_exc().decode())
+            to_screen(u'ERROR: unable to overwrite current version')
             return
-        newversion = download[0]["description"].strip()
-        if newversion == __version__:
-            downloader.to_screen(u'youtube-dl is up-to-date (' + __version__ + ')')
-            return
-        urla.close()
 
+    # Zip unix package
+    elif isinstance(globals().get('__loader__'), zipimporter):
         try:
-            urlh = compat_urllib_request.urlopen(BIN_URL)
+            urlh = compat_urllib_request.urlopen(version['bin'][0])
             newcontent = urlh.read()
             urlh.close()
         except (IOError, OSError) as err:
-            sys.exit('ERROR: unable to download latest version')
+            if verbose: to_screen(traceback.format_exc().decode())
+            to_screen(u'ERROR: unable to download latest version')
+            return
+
+        newcontent_hash = hashlib.sha256(newcontent).hexdigest()
+        if newcontent_hash != version['bin'][1]:
+            to_screen(u'ERROR: the downloaded file hash does not match. Aborting.')
+            return
 
         try:
             with open(filename, 'wb') as outf:
                 outf.write(newcontent)
         except (IOError, OSError) as err:
-            sys.exit('ERROR: unable to overwrite current version')
-
-    else:
-        downloader.to_screen(u'It looks like you installed youtube-dl with pip or setup.py. Please use that to update.')
-        return
+            if verbose: to_screen(traceback.format_exc().decode())
+            to_screen(u'ERROR: unable to overwrite current version')
+            return
 
-    downloader.to_screen(u'Updated youtube-dl. Restart youtube-dl to use the new version.')
+    to_screen(u'Updated youtube-dl. Restart youtube-dl to use the new version.')
 
 def parseOpts():
     def _readOptions(filename_bytes):
@@ -578,7 +613,7 @@ def _real_main():
 
     # Update version
     if opts.update_self:
-        updateSelf(fd, sys.argv[0])
+        update_self(fd.to_screen, opts.verbose, sys.argv[0])
 
     # Maybe do nothing
     if len(all_urls) < 1:
diff --git a/youtube_dl/utils.py b/youtube_dl/utils.py
index 463804e18..7d6041929 100644
--- a/youtube_dl/utils.py
+++ b/youtube_dl/utils.py
@@ -410,6 +410,34 @@ def encodeFilename(s):
     else:
         return s.encode(sys.getfilesystemencoding(), 'ignore')
 
+def rsa_verify(message, signature, key):
+    from struct import pack
+    from hashlib import sha256
+    from sys import version_info
+    def b(x):
+        if version_info[0] == 2: return x
+        else: return x.encode('latin1')
+    assert(type(message) == type(b('')))
+    block_size = 0
+    n = key[0]
+    while n:
+        block_size += 1
+        n >>= 8
+    signature = pow(int(signature, 16), key[1], key[0])
+    raw_bytes = []
+    while signature:
+        raw_bytes.insert(0, pack("B", signature & 0xFF))
+        signature >>= 8
+    signature = (block_size - len(raw_bytes)) * b('\x00') + b('').join(raw_bytes)
+    if signature[0:2] != b('\x00\x01'): return False
+    signature = signature[2:]
+    if not b('\x00') in signature: return False
+    signature = signature[signature.index(b('\x00'))+1:]
+    if not signature.startswith(b('\x30\x31\x30\x0D\x06\x09\x60\x86\x48\x01\x65\x03\x04\x02\x01\x05\x00\x04\x20')): return False
+    signature = signature[19:]
+    if signature != sha256(message).digest(): return False
+    return True
+
 class DownloadError(Exception):
     """Download Error exception.