tests: add device test for CoSi

tests/device_tests/test_cosi.py

@@ -0,0 +1,78 @@
+# This file is part of the TREZOR project.
+#
+# Copyright (C) 2012-2016 Marek Palatinus <slush@satoshilabs.com>
+# Copyright (C) 2012-2016 Pavol Rusnak <stick@satoshilabs.com>
+#
+# This library is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with this library.  If not, see <http://www.gnu.org/licenses/>.
+
+import unittest
+import common
+import hashlib
+
+from trezorlib import messages_pb2 as proto
+from trezorlib import ed25519raw, ed25519cosi
+
+
+class TestDeviceCosi(common.TrezorTest):
+
+    def test_cosi_commit(self):
+        self.setup_mnemonic_pin_passphrase()
+
+        digest = hashlib.sha256(b'this is a message').digest()
+
+        c0 = self.client.cosi_commit(self.client.expand_path("10018'/0'"), digest)
+        c1 = self.client.cosi_commit(self.client.expand_path("10018'/1'"), digest)
+        c2 = self.client.cosi_commit(self.client.expand_path("10018'/2'"), digest)
+
+        assert c0.pubkey != c1.pubkey
+        assert c0.pubkey != c2.pubkey
+        assert c1.pubkey != c2.pubkey
+
+        assert c0.commitment != c1.commitment
+        assert c0.commitment != c2.commitment
+        assert c1.commitment != c2.commitment
+
+        digestb = hashlib.sha256(b'this is a different message').digest()
+
+        c0b = self.client.cosi_commit(self.client.expand_path("10018'/0'"), digestb)
+        c1b = self.client.cosi_commit(self.client.expand_path("10018'/1'"), digestb)
+        c2b = self.client.cosi_commit(self.client.expand_path("10018'/2'"), digestb)
+
+        assert c0.pubkey == c0b.pubkey
+        assert c1.pubkey == c1b.pubkey
+        assert c2.pubkey == c2b.pubkey
+
+        assert c0.commitment != c0b.commitment
+        assert c1.commitment != c1b.commitment
+        assert c2.commitment != c2b.commitment
+
+    def test_cosi_sign(self):
+        self.setup_mnemonic_pin_passphrase()
+
+        digest = hashlib.sha256(b'this is a message').digest()
+
+        c0 = self.client.cosi_commit(self.client.expand_path("10018'/0'"), digest)
+        c1 = self.client.cosi_commit(self.client.expand_path("10018'/1'"), digest)
+        c2 = self.client.cosi_commit(self.client.expand_path("10018'/2'"), digest)
+
+        global_pk = ed25519cosi.combine_keys([c0.pubkey, c1.pubkey, c2.pubkey])
+        global_R = ed25519cosi.combine_keys([c0.commitment, c1.commitment, c2.commitment])
+
+        sig0 = self.client.cosi_sign(self.client.expand_path("10018'/0'"), digest, global_R, global_pk)
+        sig1 = self.client.cosi_sign(self.client.expand_path("10018'/1'"), digest, global_R, global_pk)
+        sig2 = self.client.cosi_sign(self.client.expand_path("10018'/2'"), digest, global_R, global_pk)
+
+        sig = ed25519cosi.combine_sig(global_R, [sig0.signature, sig1.signature, sig2.signature])
+
+        ed25519raw.checkvalid(sig, digest, global_pk)