Finish ed25519 and ed448 support in x509 module (#4972)

* Support ed25519 in csr/crl creation

* Tests for ed25519/x509

* Support ed448 in crt/csr/crl creation

* Tests for ed448/x509

* Support ed25519/ed448 in OCSPResponseBuilder

* Tests for eddsa in OCSPResponseBuilder

* Builder check missing in create_x509_csr

* Documentation update for ed25519+ed448 in x509

4 files changed, 488 insertions, 7 deletions

diff --git a/tests/x509/test_ocsp.py b/tests/x509/test_ocsp.py
index 3abaff50..ab3752a2 100644
--- a/tests/x509/test_ocsp.py
+++ b/tests/x509/test_ocsp.py
@@ -13,7 +13,7 @@ import pytest
 from cryptography import x509
 from cryptography.exceptions import UnsupportedAlgorithm
 from cryptography.hazmat.primitives import hashes, serialization
-from cryptography.hazmat.primitives.asymmetric import ec
+from cryptography.hazmat.primitives.asymmetric import ec, ed25519, ed448
 from cryptography.hazmat.primitives.asymmetric.padding import PKCS1v15
 from cryptography.x509 import ocsp
 
@@ -45,10 +45,12 @@ def _cert_and_issuer():
     return cert, issuer
 
 
-def _generate_root():
+def _generate_root(private_key=None, algorithm=hashes.SHA256()):
     from cryptography.hazmat.backends.openssl.backend import backend
 
-    private_key = EC_KEY_SECP256R1.private_key(backend)
+    if private_key is None:
+        private_key = EC_KEY_SECP256R1.private_key(backend)
+
     subject = x509.Name([
         x509.NameAttribute(x509.NameOID.COUNTRY_NAME, u'US'),
         x509.NameAttribute(x509.NameOID.COMMON_NAME, u'Cryptography CA'),
@@ -68,7 +70,7 @@ def _generate_root():
         datetime.datetime.now() + datetime.timedelta(days=3650)
     )
 
-    cert = builder.sign(private_key, hashes.SHA256(), backend)
+    cert = builder.sign(private_key, algorithm, backend)
     return cert, private_key
 
 
@@ -753,3 +755,71 @@ class TestOCSPResponse(object):
             resp.public_bytes("invalid")
         with pytest.raises(ValueError):
             resp.public_bytes(serialization.Encoding.PEM)
+
+
+class TestOCSPEdDSA(object):
+    @pytest.mark.supported(
+        only_if=lambda backend: backend.ed25519_supported(),
+        skip_message="Requires OpenSSL with Ed25519 support / OCSP"
+    )
+    def test_sign_ed25519(self, backend):
+        builder = ocsp.OCSPResponseBuilder()
+        cert, issuer = _cert_and_issuer()
+        private_key = ed25519.Ed25519PrivateKey.generate()
+        root_cert, private_key = _generate_root(private_key, None)
+        current_time = datetime.datetime.utcnow().replace(microsecond=0)
+        this_update = current_time - datetime.timedelta(days=1)
+        next_update = this_update + datetime.timedelta(days=7)
+        revoked_date = this_update - datetime.timedelta(days=300)
+        builder = builder.responder_id(
+            ocsp.OCSPResponderEncoding.NAME, root_cert
+        ).add_response(
+            cert, issuer, hashes.SHA1(), ocsp.OCSPCertStatus.REVOKED,
+            this_update, next_update, revoked_date,
+            x509.ReasonFlags.key_compromise
+        )
+        resp = builder.sign(private_key, None)
+        assert resp.certificate_status == ocsp.OCSPCertStatus.REVOKED
+        assert resp.revocation_time == revoked_date
+        assert resp.revocation_reason is x509.ReasonFlags.key_compromise
+        assert resp.this_update == this_update
+        assert resp.next_update == next_update
+        assert resp.signature_hash_algorithm is None
+        assert (resp.signature_algorithm_oid ==
+                x509.SignatureAlgorithmOID.ED25519)
+        private_key.public_key().verify(
+            resp.signature, resp.tbs_response_bytes
+        )
+
+    @pytest.mark.supported(
+        only_if=lambda backend: backend.ed448_supported(),
+        skip_message="Requires OpenSSL with Ed448 support / OCSP"
+    )
+    def test_sign_ed448(self, backend):
+        builder = ocsp.OCSPResponseBuilder()
+        cert, issuer = _cert_and_issuer()
+        private_key = ed448.Ed448PrivateKey.generate()
+        root_cert = _generate_root(private_key, None)[0]
+        current_time = datetime.datetime.utcnow().replace(microsecond=0)
+        this_update = current_time - datetime.timedelta(days=1)
+        next_update = this_update + datetime.timedelta(days=7)
+        revoked_date = this_update - datetime.timedelta(days=300)
+        builder = builder.responder_id(
+            ocsp.OCSPResponderEncoding.NAME, root_cert
+        ).add_response(
+            cert, issuer, hashes.SHA1(), ocsp.OCSPCertStatus.REVOKED,
+            this_update, next_update, revoked_date,
+            x509.ReasonFlags.key_compromise
+        )
+        resp = builder.sign(private_key, None)
+        assert resp.certificate_status == ocsp.OCSPCertStatus.REVOKED
+        assert resp.revocation_time == revoked_date
+        assert resp.revocation_reason is x509.ReasonFlags.key_compromise
+        assert resp.this_update == this_update
+        assert resp.next_update == next_update
+        assert resp.signature_hash_algorithm is None
+        assert (resp.signature_algorithm_oid ==
+                x509.SignatureAlgorithmOID.ED448)
+        private_key.public_key().verify(
+            resp.signature, resp.tbs_response_bytes
+        )
diff --git a/tests/x509/test_x509.py b/tests/x509/test_x509.py
index 540a814a..8a8507bd 100644
--- a/tests/x509/test_x509.py
+++ b/tests/x509/test_x509.py
@@ -28,7 +28,7 @@ from cryptography.hazmat.backends.interfaces import (
 )
 from cryptography.hazmat.primitives import hashes, serialization
 from cryptography.hazmat.primitives.asymmetric import (
-    dsa, ec, ed25519, padding, rsa
+    dsa, ec, ed25519, ed448, padding, rsa
 )
 from cryptography.hazmat.primitives.asymmetric.utils import (
     decode_dss_signature
@@ -2234,6 +2234,58 @@ class TestCertificateBuilder(object):
         with pytest.raises(ValueError):
             builder.sign(private_key, hashes.SHA256(), backend)
 
+    @pytest.mark.supported(
+        only_if=lambda backend: backend.ed25519_supported(),
+        skip_message="Requires OpenSSL with Ed25519 support"
+    )
+    @pytest.mark.requires_backend_interface(interface=X509Backend)
+    def test_request_with_unsupported_hash_ed25519(self, backend):
+        private_key = ed25519.Ed25519PrivateKey.generate()
+        builder = x509.CertificateSigningRequestBuilder().subject_name(
+            x509.Name([x509.NameAttribute(NameOID.COUNTRY_NAME, u'US')])
+        )
+
+        with pytest.raises(ValueError):
+            builder.sign(private_key, hashes.SHA256(), backend)
+
+    @pytest.mark.supported(
+        only_if=lambda backend: backend.ed448_supported(),
+        skip_message="Requires OpenSSL with Ed448 support"
+    )
+    @pytest.mark.requires_backend_interface(interface=X509Backend)
+    def test_sign_with_unsupported_hash_ed448(self, backend):
+        private_key = ed448.Ed448PrivateKey.generate()
+        builder = x509.CertificateBuilder().subject_name(
+            x509.Name([x509.NameAttribute(NameOID.COUNTRY_NAME, u'US')])
+        ).issuer_name(
+            x509.Name([x509.NameAttribute(NameOID.COUNTRY_NAME, u'US')])
+        ).serial_number(
+            1
+        ).public_key(
+            private_key.public_key()
+        ).not_valid_before(
+            datetime.datetime(2002, 1, 1, 12, 1)
+        ).not_valid_after(
+            datetime.datetime(2032, 1, 1, 12, 1)
+        )
+
+        with pytest.raises(ValueError):
+            builder.sign(private_key, hashes.SHA256(), backend)
+
+    @pytest.mark.supported(
+        only_if=lambda backend: backend.ed448_supported(),
+        skip_message="Requires OpenSSL with Ed448 support"
+    )
+    @pytest.mark.requires_backend_interface(interface=X509Backend)
+    def test_request_with_unsupported_hash_ed448(self, backend):
+        private_key = ed448.Ed448PrivateKey.generate()
+        builder = x509.CertificateSigningRequestBuilder().subject_name(
+            x509.Name([x509.NameAttribute(NameOID.COUNTRY_NAME, u'US')])
+        )
+
+        with pytest.raises(ValueError):
+            builder.sign(private_key, hashes.SHA256(), backend)
+
     @pytest.mark.requires_backend_interface(interface=RSABackend)
     @pytest.mark.requires_backend_interface(interface=X509Backend)
     @pytest.mark.supported(
@@ -2492,6 +2544,97 @@ class TestCertificateBuilder(object):
         assert isinstance(cert.signature_hash_algorithm, hashes.SHA256)
         assert isinstance(cert.public_key(), ed25519.Ed25519PublicKey)
 
+    @pytest.mark.supported(
+        only_if=lambda backend: backend.ed448_supported(),
+        skip_message="Requires OpenSSL with Ed448 support"
+    )
+    @pytest.mark.requires_backend_interface(interface=X509Backend)
+    def test_build_cert_with_ed448(self, backend):
+        issuer_private_key = ed448.Ed448PrivateKey.generate()
+        subject_private_key = ed448.Ed448PrivateKey.generate()
+
+        not_valid_before = datetime.datetime(2002, 1, 1, 12, 1)
+        not_valid_after = datetime.datetime(2030, 12, 31, 8, 30)
+
+        builder = x509.CertificateBuilder().serial_number(
+            777
+        ).issuer_name(x509.Name([
+            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
+        ])).subject_name(x509.Name([
+            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
+        ])).public_key(
+            subject_private_key.public_key()
+        ).add_extension(
+            x509.BasicConstraints(ca=False, path_length=None), True,
+        ).add_extension(
+            x509.SubjectAlternativeName([x509.DNSName(u"cryptography.io")]),
+            critical=False,
+        ).not_valid_before(
+            not_valid_before
+        ).not_valid_after(
+            not_valid_after
+        )
+
+        cert = builder.sign(issuer_private_key, None, backend)
+        issuer_private_key.public_key().verify(
+            cert.signature, cert.tbs_certificate_bytes
+        )
+        assert cert.signature_algorithm_oid == SignatureAlgorithmOID.ED448
+        assert cert.signature_hash_algorithm is None
+        assert isinstance(cert.public_key(), ed448.Ed448PublicKey)
+        assert cert.version is x509.Version.v3
+        assert cert.not_valid_before == not_valid_before
+        assert cert.not_valid_after == not_valid_after
+        basic_constraints = cert.extensions.get_extension_for_oid(
+            ExtensionOID.BASIC_CONSTRAINTS
+        )
+        assert basic_constraints.value.ca is False
+        assert basic_constraints.value.path_length is None
+        subject_alternative_name = cert.extensions.get_extension_for_oid(
+            ExtensionOID.SUBJECT_ALTERNATIVE_NAME
+        )
+        assert list(subject_alternative_name.value) == [
+            x509.DNSName(u"cryptography.io"),
+        ]
+
+    @pytest.mark.supported(
+        only_if=lambda backend: backend.ed448_supported(),
+        skip_message="Requires OpenSSL with Ed448 support"
+    )
+    @pytest.mark.requires_backend_interface(interface=X509Backend)
+    @pytest.mark.requires_backend_interface(interface=RSABackend)
+    def test_build_cert_with_public_ed448_rsa_sig(self, backend):
+        issuer_private_key = RSA_KEY_2048.private_key(backend)
+        subject_private_key = ed448.Ed448PrivateKey.generate()
+
+        not_valid_before = datetime.datetime(2002, 1, 1, 12, 1)
+        not_valid_after = datetime.datetime(2030, 12, 31, 8, 30)
+
+        builder = x509.CertificateBuilder().serial_number(
+            777
+        ).issuer_name(x509.Name([
+            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
+        ])).subject_name(x509.Name([
+            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
+        ])).public_key(
+            subject_private_key.public_key()
+        ).not_valid_before(
+            not_valid_before
+        ).not_valid_after(
+            not_valid_after
+        )
+
+        cert = builder.sign(issuer_private_key, hashes.SHA256(), backend)
+        issuer_private_key.public_key().verify(
+            cert.signature, cert.tbs_certificate_bytes, padding.PKCS1v15(),
+            cert.signature_hash_algorithm
+        )
+        assert cert.signature_algorithm_oid == (
+            SignatureAlgorithmOID.RSA_WITH_SHA256
+        )
+        assert isinstance(cert.signature_hash_algorithm, hashes.SHA256)
+        assert isinstance(cert.public_key(), ed448.Ed448PublicKey)
+
     @pytest.mark.requires_backend_interface(interface=RSABackend)
     @pytest.mark.requires_backend_interface(interface=X509Backend)
     def test_build_cert_with_rsa_key_too_small(self, backend):
@@ -3175,6 +3318,66 @@ class TestCertificateSigningRequestBuilder(object):
         assert basic_constraints.value.ca is True
         assert basic_constraints.value.path_length == 2
 
+    @pytest.mark.supported(
+        only_if=lambda backend: backend.ed25519_supported(),
+        skip_message="Requires OpenSSL with Ed25519 support"
+    )
+    @pytest.mark.requires_backend_interface(interface=X509Backend)
+    def test_build_ca_request_with_ed25519(self, backend):
+        private_key = ed25519.Ed25519PrivateKey.generate()
+
+        request = x509.CertificateSigningRequestBuilder().subject_name(
+            x509.Name([
+                x509.NameAttribute(NameOID.STATE_OR_PROVINCE_NAME, u'Texas'),
+            ])
+        ).add_extension(
+            x509.BasicConstraints(ca=True, path_length=2), critical=True
+        ).sign(private_key, None, backend)
+
+        assert request.signature_hash_algorithm is None
+        public_key = request.public_key()
+        assert isinstance(public_key, ed25519.Ed25519PublicKey)
+        subject = request.subject
+        assert isinstance(subject, x509.Name)
+        assert list(subject) == [
+            x509.NameAttribute(NameOID.STATE_OR_PROVINCE_NAME, u'Texas'),
+        ]
+        basic_constraints = request.extensions.get_extension_for_oid(
+            ExtensionOID.BASIC_CONSTRAINTS
+        )
+        assert basic_constraints.value.ca is True
+        assert basic_constraints.value.path_length == 2
+
+    @pytest.mark.supported(
+        only_if=lambda backend: backend.ed448_supported(),
+        skip_message="Requires OpenSSL with Ed448 support"
+    )
+    @pytest.mark.requires_backend_interface(interface=X509Backend)
+    def test_build_ca_request_with_ed448(self, backend):
+        private_key = ed448.Ed448PrivateKey.generate()
+
+        request = x509.CertificateSigningRequestBuilder().subject_name(
+            x509.Name([
+                x509.NameAttribute(NameOID.STATE_OR_PROVINCE_NAME, u'Texas'),
+            ])
+        ).add_extension(
+            x509.BasicConstraints(ca=True, path_length=2), critical=True
+        ).sign(private_key, None, backend)
+
+        assert request.signature_hash_algorithm is None
+        public_key = request.public_key()
+        assert isinstance(public_key, ed448.Ed448PublicKey)
+        subject = request.subject
+        assert isinstance(subject, x509.Name)
+        assert list(subject) == [
+            x509.NameAttribute(NameOID.STATE_OR_PROVINCE_NAME, u'Texas'),
+        ]
+        basic_constraints = request.extensions.get_extension_for_oid(
+            ExtensionOID.BASIC_CONSTRAINTS
+        )
+        assert basic_constraints.value.ca is True
+        assert basic_constraints.value.path_length == 2
+
     @pytest.mark.requires_backend_interface(interface=DSABackend)
     def test_build_ca_request_with_dsa(self, backend):
         private_key = DSA_KEY_2048.private_key(backend)
@@ -4420,6 +4623,26 @@ class TestEd25519Certificate(object):
         assert cert.signature_algorithm_oid == SignatureAlgorithmOID.ED25519
 
 
+@pytest.mark.supported(
+    only_if=lambda backend: backend.ed448_supported(),
+    skip_message="Requires OpenSSL with Ed448 support"
+)
+@pytest.mark.requires_backend_interface(interface=X509Backend)
+class TestEd448Certificate(object):
+    def test_load_pem_cert(self, backend):
+        cert = _load_cert(
+            os.path.join("x509", "ed448", "root-ed448.pem"),
+            x509.load_pem_x509_certificate,
+            backend
+        )
+        # self-signed, so this will work
+        cert.public_key().verify(cert.signature, cert.tbs_certificate_bytes)
+        assert isinstance(cert, x509.Certificate)
+        assert cert.serial_number == 448
+        assert cert.signature_hash_algorithm is None
+        assert cert.signature_algorithm_oid == SignatureAlgorithmOID.ED448
+
+
 def test_random_serial_number(monkeypatch):
     sample_data = os.urandom(20)
 
diff --git a/tests/x509/test_x509_crlbuilder.py b/tests/x509/test_x509_crlbuilder.py
index b9afa702..04244c1b 100644
--- a/tests/x509/test_x509_crlbuilder.py
+++ b/tests/x509/test_x509_crlbuilder.py
@@ -15,8 +15,10 @@ from cryptography.hazmat.backends.interfaces import (
     DSABackend, EllipticCurveBackend, RSABackend, X509Backend
 )
 from cryptography.hazmat.primitives import hashes
-from cryptography.hazmat.primitives.asymmetric import ec
-from cryptography.x509.oid import AuthorityInformationAccessOID, NameOID
+from cryptography.hazmat.primitives.asymmetric import ec, ed25519, ed448
+from cryptography.x509.oid import (
+    AuthorityInformationAccessOID, NameOID, SignatureAlgorithmOID
+)
 
 from ..hazmat.primitives.fixtures_dsa import DSA_KEY_2048
 from ..hazmat.primitives.fixtures_ec import EC_KEY_SECP256R1
@@ -379,6 +381,54 @@ class TestCertificateRevocationListBuilder(object):
         with pytest.raises(TypeError):
             builder.sign(private_key, object(), backend)
 
+    @pytest.mark.supported(
+        only_if=lambda backend: backend.ed25519_supported(),
+        skip_message="Requires OpenSSL with Ed25519 support"
+    )
+    @pytest.mark.requires_backend_interface(interface=X509Backend)
+    def test_sign_with_invalid_hash_ed25519(self, backend):
+        private_key = ed25519.Ed25519PrivateKey.generate()
+        last_update = datetime.datetime(2002, 1, 1, 12, 1)
+        next_update = datetime.datetime(2030, 1, 1, 12, 1)
+        builder = x509.CertificateRevocationListBuilder().issuer_name(
+            x509.Name([
+                x509.NameAttribute(NameOID.COMMON_NAME, u"cryptography.io CA")
+            ])
+        ).last_update(
+            last_update
+        ).next_update(
+            next_update
+        )
+
+        with pytest.raises(ValueError):
+            builder.sign(private_key, object(), backend)
+        with pytest.raises(ValueError):
+            builder.sign(private_key, hashes.SHA256(), backend)
+
+    @pytest.mark.supported(
+        only_if=lambda backend: backend.ed448_supported(),
+        skip_message="Requires OpenSSL with Ed448 support"
+    )
+    @pytest.mark.requires_backend_interface(interface=X509Backend)
+    def test_sign_with_invalid_hash_ed448(self, backend):
+        private_key = ed448.Ed448PrivateKey.generate()
+        last_update = datetime.datetime(2002, 1, 1, 12, 1)
+        next_update = datetime.datetime(2030, 1, 1, 12, 1)
+        builder = x509.CertificateRevocationListBuilder().issuer_name(
+            x509.Name([
+                x509.NameAttribute(NameOID.COMMON_NAME, u"cryptography.io CA")
+            ])
+        ).last_update(
+            last_update
+        ).next_update(
+            next_update
+        )
+
+        with pytest.raises(ValueError):
+            builder.sign(private_key, object(), backend)
+        with pytest.raises(ValueError):
+            builder.sign(private_key, hashes.SHA256(), backend)
+
     @pytest.mark.requires_backend_interface(interface=DSABackend)
     @pytest.mark.requires_backend_interface(interface=X509Backend)
     def test_sign_dsa_key(self, backend):
@@ -468,6 +518,104 @@ class TestCertificateRevocationListBuilder(object):
         assert ext.critical is False
         assert ext.value == invalidity_date
 
+    @pytest.mark.supported(
+        only_if=lambda backend: backend.ed25519_supported(),
+        skip_message="Requires OpenSSL with Ed25519 support"
+    )
+    @pytest.mark.requires_backend_interface(interface=X509Backend)
+    def test_sign_ed25519_key(self, backend):
+        private_key = ed25519.Ed25519PrivateKey.generate()
+        invalidity_date = x509.InvalidityDate(
+            datetime.datetime(2002, 1, 1, 0, 0)
+        )
+        ian = x509.IssuerAlternativeName([
+            x509.UniformResourceIdentifier(u"https://cryptography.io"),
+        ])
+        revoked_cert0 = x509.RevokedCertificateBuilder().serial_number(
+            2
+        ).revocation_date(
+            datetime.datetime(2012, 1, 1, 1, 1)
+        ).add_extension(
+            invalidity_date, False
+        ).build(backend)
+        last_update = datetime.datetime(2002, 1, 1, 12, 1)
+        next_update = datetime.datetime(2030, 1, 1, 12, 1)
+        builder = x509.CertificateRevocationListBuilder().issuer_name(
+            x509.Name([
+                x509.NameAttribute(NameOID.COMMON_NAME, u"cryptography.io CA")
+            ])
+        ).last_update(
+            last_update
+        ).next_update(
+            next_update
+        ).add_revoked_certificate(
+            revoked_cert0
+        ).add_extension(
+            ian, False
+        )
+
+        crl = builder.sign(private_key, None, backend)
+        assert crl.signature_hash_algorithm is None
+        assert crl.signature_algorithm_oid == SignatureAlgorithmOID.ED25519
+        assert crl.extensions.get_extension_for_class(
+            x509.IssuerAlternativeName
+        ).value == ian
+        assert crl[0].serial_number == revoked_cert0.serial_number
+        assert crl[0].revocation_date == revoked_cert0.revocation_date
+        assert len(crl[0].extensions) == 1
+        ext = crl[0].extensions.get_extension_for_class(x509.InvalidityDate)
+        assert ext.critical is False
+        assert ext.value == invalidity_date
+
+    @pytest.mark.supported(
+        only_if=lambda backend: backend.ed448_supported(),
+        skip_message="Requires OpenSSL with Ed448 support"
+    )
+    @pytest.mark.requires_backend_interface(interface=X509Backend)
+    def test_sign_ed448_key(self, backend):
+        private_key = ed448.Ed448PrivateKey.generate()
+        invalidity_date = x509.InvalidityDate(
+            datetime.datetime(2002, 1, 1, 0, 0)
+        )
+        ian = x509.IssuerAlternativeName([
+            x509.UniformResourceIdentifier(u"https://cryptography.io"),
+        ])
+        revoked_cert0 = x509.RevokedCertificateBuilder().serial_number(
+            2
+        ).revocation_date(
+            datetime.datetime(2012, 1, 1, 1, 1)
+        ).add_extension(
+            invalidity_date, False
+        ).build(backend)
+        last_update = datetime.datetime(2002, 1, 1, 12, 1)
+        next_update = datetime.datetime(2030, 1, 1, 12, 1)
+        builder = x509.CertificateRevocationListBuilder().issuer_name(
+            x509.Name([
+                x509.NameAttribute(NameOID.COMMON_NAME, u"cryptography.io CA")
+            ])
+        ).last_update(
+            last_update
+        ).next_update(
+            next_update
+        ).add_revoked_certificate(
+            revoked_cert0
+        ).add_extension(
+            ian, False
+        )
+
+        crl = builder.sign(private_key, None, backend)
+        assert crl.signature_hash_algorithm is None
+        assert crl.signature_algorithm_oid == SignatureAlgorithmOID.ED448
+        assert crl.extensions.get_extension_for_class(
+            x509.IssuerAlternativeName
+        ).value == ian
+        assert crl[0].serial_number == revoked_cert0.serial_number
+        assert crl[0].revocation_date == revoked_cert0.revocation_date
+        assert len(crl[0].extensions) == 1
+        ext = crl[0].extensions.get_extension_for_class(x509.InvalidityDate)
+        assert ext.critical is False
+        assert ext.value == invalidity_date
+
     @pytest.mark.requires_backend_interface(interface=DSABackend)
     @pytest.mark.requires_backend_interface(interface=X509Backend)
     def test_dsa_key_sign_md5(self, backend):
diff --git a/tests/x509/test_x509_ext.py b/tests/x509/test_x509_ext.py
index cf757abd..10d217ab 100644
--- a/tests/x509/test_x509_ext.py
+++ b/tests/x509/test_x509_ext.py
@@ -1641,6 +1641,46 @@ class TestSubjectKeyIdentifierExtension(object):
         )
         assert ext.value == ski
 
+    @pytest.mark.supported(
+        only_if=lambda backend: backend.ed25519_supported(),
+        skip_message="Requires OpenSSL with Ed25519 support"
+    )
+    @pytest.mark.requires_backend_interface(interface=X509Backend)
+    def test_from_ed25519_public_key(self, backend):
+        cert = _load_cert(
+            os.path.join("x509", "ed25519", "root-ed25519.pem"),
+            x509.load_pem_x509_certificate,
+            backend
+        )
+
+        ext = cert.extensions.get_extension_for_oid(
+            ExtensionOID.SUBJECT_KEY_IDENTIFIER
+        )
+        ski = x509.SubjectKeyIdentifier.from_public_key(
+            cert.public_key()
+        )
+        assert ext.value == ski
+
+    @pytest.mark.supported(
+        only_if=lambda backend: backend.ed448_supported(),
+        skip_message="Requires OpenSSL with Ed448 support"
+    )
+    @pytest.mark.requires_backend_interface(interface=X509Backend)
+    def test_from_ed448_public_key(self, backend):
+        cert = _load_cert(
+            os.path.join("x509", "ed448", "root-ed448.pem"),
+            x509.load_pem_x509_certificate,
+            backend
+        )
+
+        ext = cert.extensions.get_extension_for_oid(
+            ExtensionOID.SUBJECT_KEY_IDENTIFIER
+        )
+        ski = x509.SubjectKeyIdentifier.from_public_key(
+            cert.public_key()
+        )
+        assert ext.value == ski
+
 
 @pytest.mark.requires_backend_interface(interface=RSABackend)
 @pytest.mark.requires_backend_interface(interface=X509Backend)