[tor-commits] [stem/master] Fix certificate byte encoding

[atagar at torproject.org]

commit ae73fb878f2895482f5a87eb9b7c94387054161b
Author: Damian Johnson <atagar at torproject.org>
Date:   Sat Oct 12 14:18:17 2019 -0700

    Fix certificate byte encoding
    
    ======================================================================
    ERROR: test_encode_decode_certificate
    ----------------------------------------------------------------------
    Traceback (most recent call last):
      File "/home/atagar/Desktop/stem/test/require.py", line 57, in wrapped
        return func(self, *args, **kwargs)
      File "/home/atagar/Desktop/stem/test/unit/descriptor/certificate.py", line 217, in test_encode_decode_certificate
        ed_cert_bytes = my_ed_cert.encode()
      File "/home/atagar/Desktop/stem/stem/descriptor/certificate.py", line 418, in encode
        obj += self.version.to_bytes(1, 'big')
    AttributeError: 'int' object has no attribute 'to_bytes'
---
 stem/descriptor/certificate.py      | 28 +++++++++++++++-------------
 test/unit/descriptor/certificate.py |  2 +-
 2 files changed, 16 insertions(+), 14 deletions(-)

diff --git a/stem/descriptor/certificate.py b/stem/descriptor/certificate.py
index cdc44e53..b83d58a5 100644
--- a/stem/descriptor/certificate.py
+++ b/stem/descriptor/certificate.py
@@ -80,6 +80,7 @@ import stem.util.enum
 import stem.util.str_tools
 import stem.util
 
+from stem.client.datatype import Size
 from cryptography.hazmat.primitives import serialization
 
 ED25519_HEADER_LENGTH = 40
@@ -380,6 +381,7 @@ class MyED25519Certificate(object):
     """
     Build the cert extensions part of the certificate
     """
+
     n_extensions = 0
 
     # If we need to include the signing key, let's create the extension body
@@ -399,23 +401,23 @@ class MyED25519Certificate(object):
       ext_data = signing_pubkey_bytes
 
     # Now build the actual byte representation of any extensions
-    ext_obj = bytes()
-    ext_obj += n_extensions.to_bytes(1, 'big')
+    ext_obj = bytearray()
+    ext_obj += Size.CHAR.pack(n_extensions)
 
     if self.include_signing_key:
-      ext_obj += ext_length.to_bytes(2, 'big')
-      ext_obj += ext_type.to_bytes(1, 'big')
-      ext_obj += ext_flags.to_bytes(1, 'big')
+      ext_obj += Size.SHORT.pack(ext_length)
+      ext_obj += Size.CHAR.pack(ext_type)
+      ext_obj += Size.CHAR.pack(ext_flags)
       ext_obj += ext_data
 
-    return ext_obj
+    return bytes(ext_obj)
 
   def encode(self):
     """Return a bytes representation of this certificate."""
-    obj = bytes()
+    obj = bytearray()
 
     # Encode VERSION
-    obj += self.version.to_bytes(1, 'big')
+    obj += Size.CHAR.pack(self.version)
 
     # Encode CERT_TYPE
     try:
@@ -423,15 +425,15 @@ class MyED25519Certificate(object):
     except ValueError:
       raise ValueError("Bad cert type %s" % self.cert_type)
 
-    obj += cert_type_int.to_bytes(1, 'big')
+    obj += Size.CHAR.pack(cert_type_int)
 
     # Encode EXPIRATION_DATE
     expiration_seconds_since_epoch = stem.util.datetime_to_unix(self.expiration_date)
     expiration_hours_since_epoch = int(expiration_seconds_since_epoch) // 3600
-    obj += expiration_hours_since_epoch.to_bytes(4, 'big')
+    obj += Size.LONG.pack(expiration_hours_since_epoch)
 
     # Encode CERT_KEY_TYPE
-    obj += self.cert_key_type.to_bytes(1, 'big')
+    obj += Size.CHAR.pack(self.cert_key_type)
 
     # Encode CERTIFIED_KEY
     certified_pub_key_bytes = self.certified_pub_key.public_bytes(encoding=serialization.Encoding.Raw,
@@ -443,9 +445,9 @@ class MyED25519Certificate(object):
     obj += self._get_cert_extensions_bytes()
 
     # Do the signature on the body we have so far
-    obj += self._get_certificate_signature(obj)
+    obj += self._get_certificate_signature(bytes(obj))
 
-    return obj
+    return bytes(obj)
 
   def encode_for_descriptor(self):
     cert_bytes = self.encode()
diff --git a/test/unit/descriptor/certificate.py b/test/unit/descriptor/certificate.py
index 43a93f38..386fe1c1 100644
--- a/test/unit/descriptor/certificate.py
+++ b/test/unit/descriptor/certificate.py
@@ -227,5 +227,5 @@ class TestEd25519Certificate(unittest.TestCase):
     self.assertEqual(ed_cert_parsed.key_type, my_ed_cert.cert_key_type)
     self.assertEqual(ed_cert_parsed.key, my_ed_cert.certified_pub_key.public_bytes(encoding=serialization.Encoding.Raw,
                                                                                    format=serialization.PublicFormat.Raw))
-    self.assertEqual(ed_cert_parsed.get_signing_key(), my_ed_cert.signing_pub_key.public_bytes(encoding=serialization.Encoding.Raw,
+    self.assertEqual(ed_cert_parsed.signing_key(), my_ed_cert.signing_pub_key.public_bytes(encoding=serialization.Encoding.Raw,
                                                                                    format=serialization.PublicFormat.Raw))