name constraints - support leading periods
diff --git a/src/cryptography/hazmat/backends/openssl/x509.py b/src/cryptography/hazmat/backends/openssl/x509.py
index 4125848..c7ca2ad 100644
--- a/src/cryptography/hazmat/backends/openssl/x509.py
+++ b/src/cryptography/hazmat/backends/openssl/x509.py
@@ -86,13 +86,17 @@
# This is a wildcard name. We need to remove the leading wildcard,
# IDNA decode, then re-add the wildcard. Wildcard characters should
# always be left-most (RFC 2595 section 2.4).
- data = u"*." + idna.decode(data[2:])
+ decoded = u"*." + idna.decode(data[2:])
else:
# Not a wildcard, decode away. If the string has a * in it anywhere
# invalid this will raise an InvalidCodePoint
- data = idna.decode(data)
+ decoded = idna.decode(data)
+ if data.startswith(b"."):
+ # idna strips leading periods. Name constraints can have that
+ # so we need to re-add it. Sigh.
+ decoded = u"." + decoded
- return x509.DNSName(data)
+ return x509.DNSName(decoded)
elif gn.type == backend._lib.GEN_URI:
data = backend._ffi.buffer(
gn.d.uniformResourceIdentifier.data,
diff --git a/tests/test_x509_ext.py b/tests/test_x509_ext.py
index 15ee118..0ef84e7 100644
--- a/tests/test_x509_ext.py
+++ b/tests/test_x509_ext.py
@@ -2076,6 +2076,44 @@
excluded_subtrees=None
)
+ def test_permitted_with_leading_period(self, backend):
+ cert = _load_cert(
+ os.path.join(
+ "x509", "custom", "nc_permitted.pem"
+ ),
+ x509.load_pem_x509_certificate,
+ backend
+ )
+ nc = cert.extensions.get_extension_for_oid(
+ x509.OID_NAME_CONSTRAINTS
+ ).value
+ assert nc == x509.NameConstraints(
+ permitted_subtrees=[
+ x509.DNSName(u".cryptography.io"),
+ x509.UniformResourceIdentifier(u"ftp://cryptography.test")
+ ],
+ excluded_subtrees=None
+ )
+
+ def test_excluded_with_leading_period(self, backend):
+ cert = _load_cert(
+ os.path.join(
+ "x509", "custom", "nc_excluded.pem"
+ ),
+ x509.load_pem_x509_certificate,
+ backend
+ )
+ nc = cert.extensions.get_extension_for_oid(
+ x509.OID_NAME_CONSTRAINTS
+ ).value
+ assert nc == x509.NameConstraints(
+ permitted_subtrees=None,
+ excluded_subtrees=[
+ x509.DNSName(u".cryptography.io"),
+ x509.UniformResourceIdentifier(u"gopher://cryptography.test")
+ ]
+ )
+
class TestDistributionPoint(object):
def test_distribution_point_full_name_not_general_names(self):