Add keypair to NodeMaker.create_mutable_file

Previously `NodeMaker` always took responsibility for generating a keypair to
use.  Now the caller may supply one.

src/allmydata/crypto/rsa.py

@@ -9,17 +9,11 @@ features of any objects that `cryptography` documents.
 
 That is, the public and private keys are opaque objects; DO NOT depend
 on any of their methods.
-
-Ported to Python 3.
 """
-from __future__ import absolute_import
-from __future__ import division
-from __future__ import print_function
-from __future__ import unicode_literals
 
-from future.utils import PY2
-if PY2:
-    from builtins import filter, map, zip, ascii, chr, hex, input, next, oct, open, pow, round, super, bytes, dict, list, object, range, str, max, min  # noqa: F401
+from __future__ import annotations
+
+from typing import TypeVar
 
 from cryptography.exceptions import InvalidSignature
 from cryptography.hazmat.backends import default_backend
@@ -30,6 +24,8 @@ from cryptography.hazmat.primitives.serialization import load_der_private_key, l
 
 from allmydata.crypto.error import BadSignature
 
+PublicKey = TypeVar("PublicKey", bound=rsa.RSAPublicKey)
+PrivateKey = TypeVar("PrivateKey", bound=rsa.RSAPrivateKey)
 
 # This is the value that was used by `pycryptopp`, and we must continue to use it for
 # both backwards compatibility and interoperability.

src/allmydata/nodemaker.py

@@ -1,17 +1,12 @@
 """
-Ported to Python 3.
+Create file nodes of various types.
 """
-from __future__ import absolute_import
-from __future__ import division
-from __future__ import print_function
-from __future__ import unicode_literals
 
-from future.utils import PY2
-if PY2:
-    from future.builtins import filter, map, zip, ascii, chr, hex, input, next, oct, open, pow, round, super, bytes, dict, list, object, range, str, max, min  # noqa: F401
+from __future__ import annotations
 
 import weakref
 from zope.interface import implementer
+from twisted.internet.defer import succeed
 from allmydata.util.assertutil import precondition
 from allmydata.interfaces import INodeMaker
 from allmydata.immutable.literal import LiteralFileNode
@@ -22,6 +17,7 @@ from allmydata.mutable.publish import MutableData
 from allmydata.dirnode import DirectoryNode, pack_children
 from allmydata.unknown import UnknownNode
 from allmydata.blacklist import ProhibitedNode
+from allmydata.crypto.rsa import PublicKey, PrivateKey
 from allmydata import uri
 
 
@@ -126,12 +122,15 @@ class NodeMaker(object):
             return self._create_dirnode(filenode)
         return None
 
-    def create_mutable_file(self, contents=None, version=None):
+    def create_mutable_file(self, contents=None, version=None, keypair: tuple[PublicKey, PrivateKey] | None = None):
         if version is None:
             version = self.mutable_file_default
         n = MutableFileNode(self.storage_broker, self.secret_holder,
                             self.default_encoding_parameters, self.history)
-        d = self.key_generator.generate()
+        if keypair is None:
+            d = self.key_generator.generate()
+        else:
+            d = succeed(keypair)
         d.addCallback(n.create_with_keys, contents, version=version)
         d.addCallback(lambda res: n)
         return d

src/allmydata/test/mutable/test_filenode.py

@@ -30,6 +30,7 @@ from allmydata.mutable.publish import MutableData
 from ..test_download import PausingConsumer, PausingAndStoppingConsumer, \
      StoppingConsumer, ImmediatelyStoppingConsumer
 from .. import common_util as testutil
+from ...crypto.rsa import create_signing_keypair
 from .util import (
     FakeStorage,
     make_nodemaker_with_peers,
@@ -65,6 +66,16 @@ class Filenode(AsyncBrokenTestCase, testutil.ShouldFailMixin):
         d.addCallback(_created)
         return d
 
+    async def test_create_with_keypair(self):
+        """
+        An SDMF can be created using a given keypair.
+        """
+        (priv, pub) = create_signing_keypair(2048)
+        node = await self.nodemaker.create_mutable_file(keypair=(pub, priv))
+        self.assertThat(
+            (node.get_privkey(), node.get_pubkey()),
+            Equals((priv, pub)),
+        )
 
     def test_create_mdmf(self):
         d = self.nodemaker.create_mutable_file(version=MDMF_VERSION)

src/allmydata/test/test_dirnode.py

@@ -1619,7 +1619,8 @@ class FakeMutableFile(object):  # type: ignore # incomplete implementation
         return defer.succeed(None)
 
 class FakeNodeMaker(NodeMaker):
-    def create_mutable_file(self, contents=b"", keysize=None, version=None):
+    def create_mutable_file(self, contents=b"", keysize=None, version=None, keypair=None):
+        assert keypair is None, "FakeNodeMaker does not support externally supplied keypairs"
         return defer.succeed(FakeMutableFile(contents))
 
 class FakeClient2(_Client):  # type: ignore  # tahoe-lafs/ticket/3573

src/allmydata/test/web/test_web.py

@@ -102,7 +102,10 @@ class FakeNodeMaker(NodeMaker):
                                    self.encoding_params, None,
                                    self.all_contents).init_from_cap(cap)
     def create_mutable_file(self, contents=b"", keysize=None,
-                            version=SDMF_VERSION):
+                            version=SDMF_VERSION,
+                            keypair=None,
+                            ):
+        assert keypair is None, "FakeNodeMaker does not support externally supplied keypairs"
         n = FakeMutableFileNode(None, None, self.encoding_params, None,
                                 self.all_contents)
         return n.create(contents, version=version)