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

[youtube-dl] / youtube-dl

diff --git a/youtube-dl b/youtube-dl
index d5ca2d4bac8239de1e11d4d89739365dfa35788f..9766d905e333fb79cc77856b41b6cad4a1cee463 100755 (executable)
--- a/youtube-dl
+++ b/youtube-dl
@@ -1,15 +1,44 @@
 #!/usr/bin/env python
 
 import sys, os
+import json, hashlib
 
 try:
     import urllib.request as compat_urllib_request
 except ImportError: # Python 2
     import urllib2 as compat_urllib_request
 
+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
+
 sys.stderr.write(u'Hi! We changed distribution method and now youtube-dl needs to update itself one more time.\n')
 sys.stderr.write(u'This will only happen once. Simply press enter to go on. Sorry for the trouble!\n')
-sys.stderr.write(u'The new location of the binaries is https://github.com/rg3/youtube-dl/downloads, not the git repository.\n\n')
+sys.stderr.write(u'From now on, get the binaries from http://rg3.github.com/youtube-dl/download.html, not from the git repository.\n\n')
 
 try:
        raw_input()
@@ -18,19 +47,39 @@ except NameError: # Python 3
 
 filename = sys.argv[0]
 
-API_URL = "https://api.github.com/repos/rg3/youtube-dl/downloads"
-BIN_URL = "https://github.com/downloads/rg3/youtube-dl/youtube-dl"
+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 not os.access(filename, os.W_OK):
     sys.exit('ERROR: no write permissions on %s' % filename)
 
 try:
-    urlh = compat_urllib_request.urlopen(BIN_URL)
+    versions_info = compat_urllib_request.urlopen(JSON_URL).read().decode('utf-8')
+    versions_info = json.loads(versions_info)
+except:
+    sys.exit(u'ERROR: can\'t obtain versions info. Please try again later.')
+if not 'signature' in versions_info:
+    sys.exit(u'ERROR: the versions file is not signed or corrupted. Aborting.')
+signature = versions_info['signature']
+del versions_info['signature']
+if not rsa_verify(json.dumps(versions_info, sort_keys=True), signature, UPDATES_RSA_KEY):
+    sys.exit(u'ERROR: the versions file signature is invalid. Aborting.')
+
+version = versions_info['versions'][versions_info['latest']]
+
+try:
+    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')
 
+newcontent_hash = hashlib.sha256(newcontent).hexdigest()
+if newcontent_hash != version['bin'][1]:
+    sys.exit(u'ERROR: the downloaded file hash does not match. Aborting.')
+
 try:
     with open(filename, 'wb') as outf:
         outf.write(newcontent)