More test cases for request signing and added helpers to verify signature

api/funkwhale_api/federation/signing.py

@@ -1,3 +1,6 @@
+import requests
+import requests_http_signature
+
 from cryptography.hazmat.primitives import serialization as crypto_serialization
 from cryptography.hazmat.primitives.asymmetric import rsa
 from cryptography.hazmat.backends import default_backend as crypto_default_backend
@@ -19,3 +22,35 @@ def get_key_pair(size=2048):
     )
 
     return private_key, public_key
+
+
+def verify(request, public_key):
+    return requests_http_signature.HTTPSignatureAuth.verify(
+        request,
+        key_resolver=lambda **kwargs: public_key
+    )
+
+
+def verify_django(django_request, public_key):
+    """
+    Given a django WSGI request, create an underlying requests.PreparedRequest
+    instance we can verify
+    """
+    headers = django_request.META.get('headers', {}).copy()
+    for h, v in list(headers.items()):
+        # we include lower-cased version of the headers for compatibility
+        # with requests_http_signature
+        headers[h.lower()] = v
+    try:
+        signature = headers['authorization']
+    except KeyError:
+        raise exceptions.MissingSignature
+
+    request = requests.Request(
+        method=django_request.method,
+        url='http://noop',
+        data=django_request.body,
+        headers=headers)
+
+    prepared_request = request.prepare()
+    return verify(request, public_key)