From 407110def426d856ac33808e4d6717ffe054ec2c Mon Sep 17 00:00:00 2001
From: Pol Henarejos <pol.henarejos@cttc.es>
Date: Tue, 14 Feb 2023 11:25:02 +0100
Subject: [PATCH] Added ECDH tests.

Signed-off-by: Pol Henarejos <pol.henarejos@cttc.es>
---
 tests/conftest.py                         |  6 ++-
 tests/pico-hsm/test_022_key_derivation.py | 52 +++++++++++++++++++++++
 tests/utils.py                            |  1 +
 3 files changed, 58 insertions(+), 1 deletion(-)
 create mode 100644 tests/pico-hsm/test_022_key_derivation.py

diff --git a/tests/conftest.py b/tests/conftest.py
index 4cc960f..d5915a1 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -335,9 +335,13 @@ class Device:
         data += c.finalize()
 
         p1 = self.get_first_free_id()
-        resp = self.send(cla=0x80, command=0x74, p1=p1, p2=0x93, data=data)
+        _ = self.send(cla=0x80, command=0x74, p1=p1, p2=0x93, data=data)
         return p1
 
+    def exchange(self, keyid, pubkey):
+        resp = self.send(cla=0x80, command=0x62, p1=keyid, p2=Algorithm.ALGO_EC_DH.value, data=pubkey.public_bytes(Encoding.X962, PublicFormat.UncompressedPoint))
+        return resp
+
 
 @pytest.fixture(scope="session")
 def device():
diff --git a/tests/pico-hsm/test_022_key_derivation.py b/tests/pico-hsm/test_022_key_derivation.py
new file mode 100644
index 0000000..e28298a
--- /dev/null
+++ b/tests/pico-hsm/test_022_key_derivation.py
@@ -0,0 +1,52 @@
+"""
+/*
+ * This file is part of the Pico HSM distribution (https://github.com/polhenarejos/pico-hsm).
+ * Copyright (c) 2022 Pol Henarejos.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 3.
+ *
+ * This program 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
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+"""
+
+import pytest
+import hashlib
+from utils import KeyType, DOPrefixes
+from cryptography.hazmat.primitives.asymmetric import rsa, ec
+from const import DEFAULT_RETRIES, DEFAULT_DKEK_SHARES, DEFAULT_DKEK
+
+def test_prepare_dkek(device):
+    device.initialize(retries=DEFAULT_RETRIES, dkek_shares=DEFAULT_DKEK_SHARES)
+    resp = device.import_dkek(DEFAULT_DKEK)
+    resp = device.import_dkek(DEFAULT_DKEK)
+    kcv = hashlib.sha256(b'\x00'*32).digest()[:8]
+    assert(bytes(resp[2:]) == kcv)
+
+@pytest.mark.parametrize(
+    "curve", [ec.SECP192R1, ec.SECP256R1, ec.SECP384R1, ec.SECP521R1, ec.SECP256K1, ec.BrainpoolP256R1, ec.BrainpoolP384R1, ec.BrainpoolP512R1]
+)
+def test_exchange_ecc(device, curve):
+    pkeyA = ec.generate_private_key(curve())
+    pbkeyA = pkeyA.public_key()
+    keyid = device.import_key(pkeyA)
+    pkeyB = ec.generate_private_key(curve())
+    pbkeyB = pkeyB.public_key()
+
+    sharedB = pkeyB.exchange(ec.ECDH(), pbkeyA)
+    sharedA = device.exchange(keyid, pbkeyB)
+
+    assert(bytes(sharedA) == sharedB)
+
+    sharedAA = pkeyA.exchange(ec.ECDH(), pbkeyB)
+    assert(bytes(sharedA) == sharedAA)
+
+    device.delete_file(DOPrefixes.KEY_PREFIX.value << 8 | keyid)
+    device.delete_file(DOPrefixes.EE_CERTIFICATE_PREFIX.value << 8 | keyid)
diff --git a/tests/utils.py b/tests/utils.py
index e5935b9..d59505c 100644
--- a/tests/utils.py
+++ b/tests/utils.py
@@ -101,6 +101,7 @@ class Algorithm(Enum):
     ALGO_EC_SHA256          = 0x73
     ALGO_EC_SHA384          = 0x74
     ALGO_EC_SHA512          = 0x75
+    ALGO_EC_DH              = 0x80
 
     ALGO_RSA_RAW            = 0x20
     ALGO_RSA_DECRYPT        = 0x21