commit 2ae8ea381830c466b54b7b383f8fe232406094e8 Author: Damian Johnson <atagar@torproject.org> Date: Mon Jun 19 12:10:58 2017 -0700 Constants for padding attributes Bit more readable this way. Also, we can drop the lower() from the hexdigest since it already is. --- stem/descriptor/server_descriptor.py | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/stem/descriptor/server_descriptor.py b/stem/descriptor/server_descriptor.py index 724684d..03008ac 100644 --- a/stem/descriptor/server_descriptor.py +++ b/stem/descriptor/server_descriptor.py @@ -76,6 +76,10 @@ except ImportError: SigningKey = collections.namedtuple('SigningKey', ['public', 'private', 'descriptor_signing_key']) +DIGEST_TYPE_INFO = b'\x00\x01' +DIGEST_PADDING = b'\xFF' +DIGEST_SEPARATOR = b'\x00' + # relay descriptors must have exactly one of the following REQUIRED_FIELDS = ( 'router', @@ -249,8 +253,8 @@ def _generate_signature(content, signing_key): # generate the digest with required PKCS1 padding so it's 128 bytes - digest = hashlib.sha1(content).hexdigest().lower().decode('hex_codec') - digest = b'\x00\x01' + (b'\xFF' * (125 - len(digest))) + b'\x00' + digest + digest = hashlib.sha1(content).hexdigest().decode('hex_codec') + digest = DIGEST_TYPE_INFO + (DIGEST_PADDING * (125 - len(digest))) + DIGEST_SEPARATOR + digest padding = padding.PSS(mgf = padding.MGF1(hashes.SHA256()), salt_length = padding.PSS.MAX_LENGTH) return base64.b64encode(signing_key.private.sign(digest, padding, hashes.SHA256()))