1 files changed, 42 insertions, 0 deletions
diff --git a/tests/wycheproof/test_x25519.py b/tests/wycheproof/test_x25519.py
new file mode 100644
index 00000000..5e6253ce
--- /dev/null
+++ b/tests/wycheproof/test_x25519.py
@@ -0,0 +1,42 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import binascii
+
+import pytest
+
+from cryptography.hazmat.backends.interfaces import DHBackend
+from cryptography.hazmat.primitives.asymmetric.x25519 import (
+    X25519PrivateKey, X25519PublicKey
+)
+
+
+@pytest.mark.supported(
+    only_if=lambda backend: backend.x25519_supported(),
+    skip_message="Requires OpenSSL with X25519 support"
+)
+@pytest.mark.requires_backend_interface(interface=DHBackend)
+@pytest.mark.wycheproof_tests("x25519_test.json")
+def test_x25519(backend, wycheproof):
+    assert list(wycheproof.testgroup.items()) == [("curve", "curve25519")]
+
+    private_key = X25519PrivateKey._from_private_bytes(
+        binascii.unhexlify(wycheproof.testcase["private"])
+    )
+    public_key = X25519PublicKey.from_public_bytes(
+        binascii.unhexlify(wycheproof.testcase["public"])
+    )
+
+    assert wycheproof.valid or wycheproof.acceptable
+
+    expected = binascii.unhexlify(wycheproof.testcase["shared"])
+    if expected == b"\x00" * 32:
+        assert wycheproof.acceptable
+        # OpenSSL returns an error on all zeros shared key
+        with pytest.raises(ValueError):
+            private_key.exchange(public_key)
+    else:
+        assert private_key.exchange(public_key) == expected