From 5f6d9c3e27b1bc3d85b0b729ee924399dc4b7486 Mon Sep 17 00:00:00 2001
From: Jonathan Bennett <jbennett@incomsystems.biz>
Date: Thu, 26 Sep 2024 19:33:08 -0500
Subject: [PATCH] Add pkc test (#4878)

* Add a second delay() to get the unit tests running on Rak4631

* Add test_PKC_Decrypt

* Remove cruft from test case
---
 src/mesh/CryptoEngine.cpp      |  2 ++
 test/test_crypto/test_main.cpp | 38 ++++++++++++++++++++++++++++++++++
 2 files changed, 40 insertions(+)

diff --git a/src/mesh/CryptoEngine.cpp b/src/mesh/CryptoEngine.cpp
index f9d7b4ad29..7b5c8f2bd3 100644
--- a/src/mesh/CryptoEngine.cpp
+++ b/src/mesh/CryptoEngine.cpp
@@ -102,6 +102,7 @@ bool CryptoEngine::decryptCurve25519(uint32_t fromNode, uint64_t packetNum, size
     uint8_t *auth; // set to last 8 bytes of text?
     uint32_t extraNonce; // pointer was not really used
     auth = bytes + numBytes - 12;
+#ifndef PIO_UNIT_TESTING
     memcpy(&extraNonce, auth +8, 4); // do not use dereference on potential non aligned pointers : (uint32_t *)(auth + 8);
     LOG_INFO("Random nonce value: %d\n", extraNonce);
     meshtastic_NodeInfoLite *node = nodeDB->getMeshNode(fromNode);
@@ -115,6 +116,7 @@ bool CryptoEngine::decryptCurve25519(uint32_t fromNode, uint64_t packetNum, size
     if (!crypto->setDHKey(fromNode)) {
         return false;
     }
+#endif
     initNonce(fromNode, packetNum, extraNonce);
     printBytes("Attempting decrypt using nonce: ", nonce, 13);
     printBytes("Attempting decrypt using shared_key starting with: ", shared_key, 8);
diff --git a/test/test_crypto/test_main.cpp b/test/test_crypto/test_main.cpp
index 0c820178ac..cbe3660486 100644
--- a/test/test_crypto/test_main.cpp
+++ b/test/test_crypto/test_main.cpp
@@ -98,7 +98,44 @@ void test_DH25519(void)
     HexToBytes(private_key, "18630f93598637c35da623a74559cf944374a559114c7937811041fc8605564a");
     crypto->setDHPrivateKey(private_key);
     TEST_ASSERT(!crypto->setDHPublicKey(public_key)); // Weak public key results in 0 shared key
+
+    HexToBytes(public_key, "f7e13a1a067d2f4e1061bf9936fde5be6b0c2494a8f809cbac7f290ef719e91c");
+    HexToBytes(private_key, "10300724f3bea134eb1575245ef26ff9b8ccd59849cd98ce1a59002fe1d5986c");
+    HexToBytes(expected_shared, "24becd5dfed9e9289ba2e15b82b0d54f8e9aacb72f5e4248c58d8d74b451ce76");
+    crypto->setDHPrivateKey(private_key);
+    TEST_ASSERT(crypto->setDHPublicKey(public_key));
+    crypto->hash(crypto->shared_key, 32);
+    TEST_ASSERT_EQUAL_MEMORY(expected_shared, crypto->shared_key, 32);
+}
+
+void test_PKC_Decrypt(void)
+{
+    uint8_t private_key[32];
+    uint8_t public_key[32];
+    uint8_t expected_shared[32];
+    uint8_t expected_decrypted[32];
+    uint8_t radioBytes[128] __attribute__((__aligned__));
+    uint8_t decrypted[128] __attribute__((__aligned__));
+    uint8_t expected_nonce[16];
+
+    uint32_t fromNode;
+    HexToBytes(public_key, "db18fc50eea47f00251cb784819a3cf5fc361882597f589f0d7ff820e8064457");
+    HexToBytes(private_key, "a00330633e63522f8a4d81ec6d9d1e6617f6c8ffd3a4c698229537d44e522277");
+    HexToBytes(expected_shared, "777b1545c9d6f9a2");
+    HexToBytes(expected_decrypted, "08011204746573744800");
+    HexToBytes(radioBytes, "8c646d7a2909000062d6b2136b00000040df24abfcc30a17a3d9046726099e796a1c036a792b");
+    HexToBytes(expected_nonce, "62d6b213036a792b2909000000");
+    fromNode = 0x0929;
+    crypto->setDHPrivateKey(private_key);
+    TEST_ASSERT(crypto->setDHPublicKey(public_key));
+    crypto->hash(crypto->shared_key, 32);
+    crypto->decryptCurve25519(fromNode, 0x13b2d662, 22, radioBytes + 16, decrypted);
+    TEST_ASSERT_EQUAL_MEMORY(expected_shared, crypto->shared_key, 8);
+    TEST_ASSERT_EQUAL_MEMORY(expected_nonce, crypto->nonce, 13);
+
+    TEST_ASSERT_EQUAL_MEMORY(expected_decrypted, decrypted, 10);
 }
+
 void test_AES_CTR(void)
 {
     uint8_t expected[32];
@@ -137,6 +174,7 @@ void setup()
     RUN_TEST(test_ECB_AES256);
     RUN_TEST(test_DH25519);
     RUN_TEST(test_AES_CTR);
+    RUN_TEST(test_PKC_Decrypt);
 }
 
 void loop()