Add support for RFC 7914 (#77)

4 files changed, 146 insertions, 0 deletions

diff --git a/CHANGES.txt b/CHANGES.txt
index 4dbe1fa..9797e24 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -44,6 +44,7 @@ Revision 0.2.7, released XX-09-2019
 - Added RFC8358 providing Digital Signatures on Internet-Draft Documents
 - Added RFC8209 providing BGPsec Router PKI Profile
 - Added RFC8017 providing PKCS #1 Version 2.2
+- Added RFC7914 providing scrypt Password-Based Key Derivation Function
 
 Revision 0.2.6, released 31-07-2019
 -----------------------------------
diff --git a/pyasn1_modules/rfc7914.py b/pyasn1_modules/rfc7914.py
new file mode 100644
index 0000000..99e9551
--- /dev/null
+++ b/pyasn1_modules/rfc7914.py
@@ -0,0 +1,49 @@
+#
+# This file is part of pyasn1-modules software.
+#
+# Created by Russ Housley with assistance from asn1ate v.0.6.0.
+#
+# Copyright (c) 2019, Vigil Security, LLC
+# License: http://snmplabs.com/pyasn1/license.html
+#
+#The scrypt Password-Based Key Derivation Function
+#
+# ASN.1 source from:
+# https://www.rfc-editor.org/rfc/rfc8520.txt
+# https://www.rfc-editor.org/errata/eid5871
+#
+
+from pyasn1.type import constraint
+from pyasn1.type import namedtype
+from pyasn1.type import univ
+
+from pyasn1_modules import rfc5280
+
+MAX = float('inf')
+
+
+id_scrypt = univ.ObjectIdentifier('1.3.6.1.4.1.11591.4.11')
+
+
+class Scrypt_params(univ.Sequence):
+    componentType = namedtype.NamedTypes(
+        namedtype.NamedType('salt',
+            univ.OctetString()),
+        namedtype.NamedType('costParameter',
+            univ.Integer().subtype(subtypeSpec=constraint.ValueRangeConstraint(1, MAX))),
+        namedtype.NamedType('blockSize',
+            univ.Integer().subtype(subtypeSpec=constraint.ValueRangeConstraint(1, MAX))),
+        namedtype.NamedType('parallelizationParameter',
+            univ.Integer().subtype(subtypeSpec=constraint.ValueRangeConstraint(1, MAX))),
+        namedtype.OptionalNamedType('keyLength',
+            univ.Integer().subtype(subtypeSpec=constraint.ValueRangeConstraint(1, MAX)))
+    )
+
+
+# Update the Algorithm Identifier map in rfc5280.py
+
+_algorithmIdentifierMapUpdate = {
+    id_scrypt: Scrypt_params(),
+}
+
+rfc5280.algorithmIdentifierMap.update(_algorithmIdentifierMapUpdate)
diff --git a/tests/__main__.py b/tests/__main__.py
index 36290c6..b79752f 100644
--- a/tests/__main__.py
+++ b/tests/__main__.py
@@ -60,6 +60,7 @@ suite = unittest.TestLoader().loadTestsFromNames(
      'tests.test_rfc7296.suite',
      'tests.test_rfc7894.suite',
      'tests.test_rfc7906.suite',
+     'tests.test_rfc7914.suite',
      'tests.test_rfc8017.suite',
      'tests.test_rfc8018.suite',
      'tests.test_rfc8103.suite',
diff --git a/tests/test_rfc7914.py b/tests/test_rfc7914.py
new file mode 100644
index 0000000..1ab8b8f
--- /dev/null
+++ b/tests/test_rfc7914.py
@@ -0,0 +1,95 @@
+#
+# This file is part of pyasn1-modules software.
+#
+# Created by Russ Housley
+# Copyright (c) 2019, Vigil Security, LLC
+# License: http://snmplabs.com/pyasn1/license.html
+#
+
+import sys
+
+from pyasn1.codec.der.decoder import decode as der_decode
+from pyasn1.codec.der.encoder import encode as der_encode
+
+from pyasn1_modules import pem
+from pyasn1_modules import rfc5280
+from pyasn1_modules import rfc5958
+from pyasn1_modules import rfc7914
+from pyasn1_modules import rfc8018
+
+try:
+    import unittest2 as unittest
+
+except ImportError:
+    import unittest
+
+
+# From RFC 7914, Section 13
+
+class MultiprimeRSAPrivateKeyTestCase(unittest.TestCase):
+    pem_text = """\
+MIHiME0GCSqGSIb3DQEFDTBAMB8GCSsGAQQB2kcECzASBAVNb3VzZQIDEAAAAgEI
+AgEBMB0GCWCGSAFlAwQBKgQQyYmguHMsOwzGMPoyObk/JgSBkJb47EWd5iAqJlyy
++ni5ftd6gZgOPaLQClL7mEZc2KQay0VhjZm/7MbBUNbqOAXNM6OGebXxVp6sHUAL
+iBGY/Dls7B1TsWeGObE0sS1MXEpuREuloZjcsNVcNXWPlLdZtkSH6uwWzR0PyG/Z
++ZXfNodZtd/voKlvLOw5B3opGIFaLkbtLZQwMiGtl42AS89lZg==
+"""
+
+    def setUp(self):
+        self.asn1Spec = rfc5958.EncryptedPrivateKeyInfo()
+
+    def testDerCodec(self):
+        substrate = pem.readBase64fromText(self.pem_text)
+        asn1Object, rest = der_decode(substrate, asn1Spec=self.asn1Spec)
+        assert not rest
+        assert asn1Object.prettyPrint()
+        assert der_encode(asn1Object) == substrate
+
+        ea = asn1Object['encryptionAlgorithm']
+        assert ea['algorithm'] == rfc8018.id_PBES2
+        assert ea['algorithm'] in rfc5280.algorithmIdentifierMap.keys()
+
+        params, rest = der_decode(ea['parameters'],
+            asn1Spec=rfc5280.algorithmIdentifierMap[ea['algorithm']])
+        assert not rest
+        assert params.prettyPrint()
+        assert der_encode(params) == ea['parameters']
+
+        kdf = params['keyDerivationFunc']
+        assert kdf['algorithm'] == rfc7914.id_scrypt
+        assert kdf['algorithm'] in rfc5280.algorithmIdentifierMap.keys()
+
+        kdfp, rest = der_decode(kdf['parameters'],
+            asn1Spec=rfc5280.algorithmIdentifierMap[kdf['algorithm']])
+        assert not rest
+        assert kdfp.prettyPrint()
+        assert der_encode(kdfp) == kdf['parameters']
+
+        assert kdfp['costParameter'] == 1048576
+
+    def testOpenTypes(self):
+        substrate = pem.readBase64fromText(self.pem_text)
+        asn1Object, rest = der_decode(substrate,
+            asn1Spec=self.asn1Spec,
+            decodeOpenTypes=True)
+        assert not rest
+        assert asn1Object.prettyPrint()
+        assert der_encode(asn1Object) == substrate
+
+        ea = asn1Object['encryptionAlgorithm']
+        assert ea['algorithm'] == rfc8018.id_PBES2
+
+        params = asn1Object['encryptionAlgorithm']['parameters']
+        assert params['keyDerivationFunc']['algorithm'] == rfc7914.id_scrypt
+
+        kdfp = params['keyDerivationFunc']['parameters']
+        assert kdfp['costParameter'] == 1048576
+
+
+suite = unittest.TestLoader().loadTestsFromModule(sys.modules[__name__])
+
+if __name__ == '__main__':
+    import sys
+
+    result = unittest.TextTestRunner(verbosity=2).run(suite)
+    sys.exit(not result.wasSuccessful())