wolfCrypt CSharp wrapper ECIES support and test

wrapper/CSharp/README.md

@@ -46,7 +46,7 @@ apt-get install mono-complete
 
 ```
 ./autogen.sh
-./configure --enable-keygen --enable-ed25519 --enable-curve25519 --enable-aesgcm
+./configure --enable-keygen --enable--eccencrypt --enable-ed25519 --enable-curve25519 --enable-aesgcm
 make
 make check
 sudo make install

wrapper/CSharp/user_settings.h

@@ -45,6 +45,7 @@
 #define WOLFSSL_KEY_GEN /* RSA key gen */
 #define WOLFSSL_ASN_TEMPLATE /* default */
 #define WOLFSSL_SHA3
+
 #if 0
     #define OPENSSL_EXTRA
 #endif
@@ -67,6 +68,8 @@
 #define HAVE_HKDF
 
 #undef  NO_DH
+#define HAVE_PUBLIC_FFDHE
+#define HAVE_FFDHE_2048
 #define HAVE_FFDHE_4096
 
 #undef  NO_RSA

wrapper/CSharp/wolfCrypt-Test/wolfCrypt-Test.cs

@@ -633,6 +633,106 @@ private static void hash_test(uint hashType)
         }
     } /* END hash_test */
 
+    private static void ecies_test()
+{
+    const int keySize = 32;
+    const int bufferSize = 128;
+    const string message = "Hello wolfSSL!";
+    byte[] salt = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 };
+
+    IntPtr a = IntPtr.Zero;
+    IntPtr b = IntPtr.Zero;
+    IntPtr aCtx = IntPtr.Zero;
+    IntPtr bCtx = IntPtr.Zero;
+    IntPtr rng = IntPtr.Zero;
+    IntPtr heap = IntPtr.Zero;
+
+    byte[] plaintext = new byte[bufferSize];
+    byte[] encrypted = new byte[bufferSize];
+    byte[] decrypted = new byte[bufferSize];
+
+    try
+    {
+        Console.WriteLine($"\nStarting ecies test for {keySize} key size...");
+
+        /* Create a new RNG context */
+        rng = wolfcrypt.RandomNew();
+        if (rng == IntPtr.Zero)
+        {
+            throw new Exception("RNG initialization failed.");
+        }
+
+        /* Initialize keys */
+        a = wolfcrypt.EccMakeKey(keySize);
+        b = wolfcrypt.EccMakeKey(keySize);
+        if (a == IntPtr.Zero || b == IntPtr.Zero)
+        {
+            throw new Exception("Key generation failed.");
+        }
+        Console.WriteLine("ECC key generation passed.");
+
+        /* Create ECIES contexts for encryption and decryption */
+        aCtx = wolfcrypt.EciesNewCtx((int)wolfcrypt.ecFlags.REQ_RESP_CLIENT, rng, heap);
+        bCtx = wolfcrypt.EciesNewCtx((int)wolfcrypt.ecFlags.REQ_RESP_SERVER, rng, heap);
+        if (aCtx == IntPtr.Zero || bCtx == IntPtr.Zero)
+        {
+            throw new Exception("Context creation failed.");
+        }
+        Console.WriteLine("ECC context creation passed.");
+
+        /* Set KDF salt */
+        if (wolfcrypt.EciesSetKdfSalt(aCtx, salt) != 0 ||
+            wolfcrypt.EciesSetKdfSalt(bCtx, salt) != 0)
+        {
+            throw new Exception("Failed to set KDF salt.");
+        }
+        Console.WriteLine("KDF salt setup passed.");
+
+        /* Prepare plaintext */
+        Array.Clear(plaintext, 0, plaintext.Length);
+        Array.Copy(Encoding.ASCII.GetBytes(message), plaintext, message.Length);
+        /* Pad to block size */
+        int plaintextLen = ((message.Length + (wolfcrypt.AES_BLOCK_SIZE - 1)) /
+                            wolfcrypt.AES_BLOCK_SIZE) * wolfcrypt.AES_BLOCK_SIZE;
+
+        /* Encrypt message */
+        int ret = wolfcrypt.EciesEncrypt(a, b, plaintext, (uint)plaintextLen, encrypted, aCtx);
+        if (ret < 0)
+        {
+            throw new Exception("Encryption failed.");
+        }
+
+        int encryptedLen = ret;
+        Console.WriteLine("ECC encryption passed.");
+
+        /* Decrypt message */
+        ret = wolfcrypt.EciesDecrypt(b, a, encrypted, (uint)encryptedLen, decrypted, bCtx);
+        if (ret < 0)
+        {
+            throw new Exception("Decryption failed.");
+        }
+
+        int decryptedLen = ret;
+        Console.WriteLine("ECC decryption passed.");
+
+        /* Compare decrypted text to original plaintext */
+        if (!wolfcrypt.ByteArrayVerify(plaintext, decrypted))
+        {
+            throw new Exception("Decrypted text does not match original plaintext.");
+        }
+        Console.WriteLine("Decrypted text matches original plaintext.");
+    }
+    finally
+    {
+        /* Cleanup key and context */
+        if (a != IntPtr.Zero) wolfcrypt.EccFreeKey(a);
+        if (b != IntPtr.Zero) wolfcrypt.EccFreeKey(b);
+        if (aCtx != IntPtr.Zero) wolfcrypt.EciesFreeCtx(aCtx);
+        if (bCtx != IntPtr.Zero) wolfcrypt.EciesFreeCtx(bCtx);
+        if (rng != IntPtr.Zero) wolfcrypt.RandomFree(rng);
+    }
+} /* END ecies_test */
+
     public static void standard_log(int lvl, StringBuilder msg)
     {
         Console.WriteLine(msg);
@@ -670,6 +770,8 @@ public static void Main(string[] args)
             hash_test((uint)wolfcrypt.hashType.WC_HASH_TYPE_SHA512); /* SHA-512 HASH test */
             hash_test((uint)wolfcrypt.hashType.WC_HASH_TYPE_SHA3_256); /* SHA3_256 HASH test */
 
+            ecies_test(); /* ECIES test */
+
             wolfcrypt.Cleanup();
 
             Console.WriteLine("\nAll tests completed successfully");