serve pub key, not cert

1 files changed, 12 insertions, 0 deletions

diff --git a/modules/fediverse/ap_security.py b/modules/fediverse/ap_security.py
index f7d17a2e..a466aaa5 100644
--- a/modules/fediverse/ap_security.py
+++ b/modules/fediverse/ap_security.py
@@ -1,9 +1,14 @@
 import base64, typing
 
 try:
+    from cryptography import x509
     from cryptography.hazmat.primitives import hashes, serialization
     from cryptography.hazmat.primitives.asymmetric import padding, rsa
     from cryptography.hazmat.backends import default_backend
+
+    from cryptography.hazmat.primitives.serialization import Encoding
+    from cryptography.hazmat.primitives.serialization import PublicFormat
+
     has_crypto = True
 except ModuleNotFoundError:
     has_crypto = False
@@ -21,6 +26,13 @@ class PrivateKey(object):
         self.key = _private_key(filename)
         self.id = id
 
+def public_key(key_filename: str) -> str:
+    with open(key_filename, "rb") as key_file:
+        cert = x509.load_pem_x509_certificate(key_file.read(),
+            default_backend())
+    return cert.public_key().public_bytes(
+        Encoding.PEM, PublicFormat.SubjectPublicKeyInfo).decode("ascii")
+
 def signature(key: PrivateKey, headers: typing.List[typing.Tuple[str, str]]
         ) -> str:
     sign_header_keys = " ".join(h[0].lower() for h in headers)