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dgarskedgarske
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Add HPKE (RFC 9180) C# wrapper and test
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‎wrapper/CSharp/README.md‎

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@@ -40,6 +40,8 @@ apt-get install mono-complete
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### Build wolfSSL and install
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#### System-wide install
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```
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./autogen.sh
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cp wrapper/CSharp/user_settings.h .
@@ -49,6 +51,16 @@ make check
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sudo make install
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```
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#### Local-only install (no sudo required)
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```
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./autogen.sh
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cp wrapper/CSharp/user_settings.h .
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./configure --enable-usersettings --prefix=$(pwd)/install
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make
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make install
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```
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### Build and run the wolfCrypt test wrapper
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From the `wrapper/CSharp` directory (`cd wrapper/CSharp`):
@@ -57,9 +69,22 @@ Compile wolfCrypt test:
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```
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mcs wolfCrypt-Test/wolfCrypt-Test.cs wolfSSL_CSharp/wolfCrypt.cs wolfSSL_CSharp/wolfSSL.cs wolfSSL_CSharp/X509.cs -OUT:wolfcrypttest.exe
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```
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Run with system-wide install:
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```
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mono wolfcrypttest.exe
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```
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Run with local-only install. The compile step above produced
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`wolfcrypttest.exe` inside `wrapper/CSharp/`; this run command is invoked
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from the wolfSSL project root so the relative paths line up:
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```
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LD_LIBRARY_PATH=./install/lib mono wrapper/CSharp/wolfcrypttest.exe
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```
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### Build and run the wolfSSL client/server test
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From the `wrapper/CSharp` directory (`cd wrapper/CSharp`):

‎wrapper/CSharp/user_settings.h‎

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@@ -70,6 +70,7 @@
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#define WOLFSSL_SHA512
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#define HAVE_HKDF
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#define HAVE_HPKE
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#undef NO_DH
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#define HAVE_PUBLIC_FFDHE

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

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@@ -880,6 +880,202 @@ private static void hash_test(uint hashType)
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}
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} /* END hash_test */
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private static void hpke_test(wolfcrypt.HpkeKem kem,
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wolfcrypt.HpkeKdf kdf, wolfcrypt.HpkeAead aead)
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{
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IntPtr hpke = IntPtr.Zero;
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IntPtr receiverKey = IntPtr.Zero;
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IntPtr deserializedKey = IntPtr.Zero;
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IntPtr ephemeralKey = IntPtr.Zero;
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try
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{
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Console.WriteLine("\nStarting HPKE Base mode test...");
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/* Initialize HPKE context */
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Console.WriteLine("Initializing HPKE context...");
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hpke = wolfcrypt.HpkeInit(kem, kdf, aead);
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if (hpke == IntPtr.Zero)
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{
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throw new Exception("HpkeInit failed");
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}
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Console.WriteLine("HPKE context initialization passed.");
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/* Generate receiver keypair */
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Console.WriteLine("Generating receiver keypair...");
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receiverKey = wolfcrypt.HpkeGenerateKeyPair(hpke);
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if (receiverKey == IntPtr.Zero)
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{
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throw new Exception("HpkeGenerateKeyPair (receiver) failed");
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}
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Console.WriteLine("Receiver keypair generation passed.");
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/* Serialize and deserialize public key (round-trip) */
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Console.WriteLine("Testing public key serialize/deserialize round-trip...");
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byte[] pubKeyBytes = wolfcrypt.HpkeSerializePublicKey(hpke, receiverKey);
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if (pubKeyBytes == null)
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{
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throw new Exception("HpkeSerializePublicKey failed");
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}
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Console.WriteLine($"Serialized public key length: {pubKeyBytes.Length}");
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deserializedKey = wolfcrypt.HpkeDeserializePublicKey(hpke, pubKeyBytes);
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if (deserializedKey == IntPtr.Zero)
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{
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throw new Exception("HpkeDeserializePublicKey failed");
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}
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/* Verify round-trip by re-serializing */
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byte[] pubKeyBytes2 = wolfcrypt.HpkeSerializePublicKey(hpke, deserializedKey);
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if (pubKeyBytes2 == null || !wolfcrypt.ByteArrayVerify(pubKeyBytes, pubKeyBytes2))
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{
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throw new Exception("Public key round-trip verification failed");
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}
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Console.WriteLine("Public key round-trip test passed.");
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/* Generate ephemeral keypair for sender */
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Console.WriteLine("Generating ephemeral keypair...");
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ephemeralKey = wolfcrypt.HpkeGenerateKeyPair(hpke);
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if (ephemeralKey == IntPtr.Zero)
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{
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throw new Exception("HpkeGenerateKeyPair (ephemeral) failed");
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}
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Console.WriteLine("Ephemeral keypair generation passed.");
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/* Define test data */
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byte[] info = Encoding.UTF8.GetBytes("HPKE .NET Test");
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byte[] aad = Encoding.UTF8.GetBytes("additional data");
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byte[] plaintext = Encoding.UTF8.GetBytes("Hello HPKE from wolfCrypt .NET!");
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/* Seal (encrypt) */
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Console.WriteLine("Testing HpkeSealBase...");
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byte[] encCiphertext = wolfcrypt.HpkeSealBase(hpke, ephemeralKey,
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receiverKey, info, aad, plaintext);
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if (encCiphertext == null)
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{
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throw new Exception("HpkeSealBase failed");
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}
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Console.WriteLine($"HpkeSealBase passed. Output length: {encCiphertext.Length}");
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/* Open (decrypt) */
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Console.WriteLine("Testing HpkeOpenBase...");
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byte[] decrypted = wolfcrypt.HpkeOpenBase(hpke, receiverKey,
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encCiphertext, info, aad, plaintext.Length);
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if (decrypted == null)
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{
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throw new Exception("HpkeOpenBase failed");
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}
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Console.WriteLine("HpkeOpenBase passed.");
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/* Compare plaintext and decrypted */
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if (!wolfcrypt.ByteArrayVerify(plaintext, decrypted))
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{
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throw new Exception("Decrypted text does not match original plaintext");
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}
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Console.WriteLine("HPKE Base mode test PASSED.");
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/* Test convenience overload (no ephemeral key) */
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Console.WriteLine("Testing HpkeSealBase convenience overload...");
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byte[] encCiphertext2 = wolfcrypt.HpkeSealBase(hpke, receiverKey,
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info, aad, plaintext, kem);
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if (encCiphertext2 == null)
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{
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throw new Exception("HpkeSealBase (convenience) failed");
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}
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Console.WriteLine($"HpkeSealBase convenience passed. Output length: {encCiphertext2.Length}");
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byte[] decrypted2 = wolfcrypt.HpkeOpenBase(hpke, receiverKey,
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encCiphertext2, info, aad, kem);
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if (decrypted2 == null)
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{
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throw new Exception("HpkeOpenBase (convenience) failed");
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}
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if (!wolfcrypt.ByteArrayVerify(plaintext, decrypted2))
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{
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throw new Exception("Convenience seal/open: decrypted text does not match");
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}
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Console.WriteLine("HPKE convenience overload test PASSED.");
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/* Empty plaintext round-trip - native API accepts ptSz == 0 */
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Console.WriteLine("Testing HpkeSealBase/OpenBase with empty plaintext...");
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byte[] emptyPt = new byte[0];
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byte[] encEmpty = wolfcrypt.HpkeSealBase(hpke, receiverKey,
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info, aad, emptyPt, kem);
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if (encEmpty == null)
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{
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throw new Exception("HpkeSealBase with empty plaintext failed");
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}
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byte[] decEmpty = wolfcrypt.HpkeOpenBase(hpke, receiverKey,
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encEmpty, info, aad, kem);
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if (decEmpty == null || decEmpty.Length != 0)
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{
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throw new Exception("HpkeOpenBase with empty plaintext: round-trip failed");
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}
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Console.WriteLine("Empty plaintext round-trip test PASSED.");
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/* Negative test: tampered ciphertext should fail */
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Console.WriteLine("Testing HpkeOpenBase with tampered ciphertext...");
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byte[] tampered = (byte[])encCiphertext.Clone();
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tampered[tampered.Length - 1] ^= 0xFF; /* flip last byte (in tag) */
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byte[] badResult = wolfcrypt.HpkeOpenBase(hpke, receiverKey,
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tampered, info, aad, plaintext.Length);
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if (badResult != null)
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{
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throw new Exception("HpkeOpenBase should fail with tampered ciphertext");
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}
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Console.WriteLine("Tampered ciphertext test PASSED (correctly rejected).");
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/* Negative test: mismatched AAD should fail */
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Console.WriteLine("Testing HpkeOpenBase with mismatched AAD...");
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byte[] wrongAad = Encoding.UTF8.GetBytes("wrong aad");
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badResult = wolfcrypt.HpkeOpenBase(hpke, receiverKey,
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encCiphertext, info, wrongAad, plaintext.Length);
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if (badResult != null)
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{
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throw new Exception("HpkeOpenBase should fail with mismatched AAD");
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}
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Console.WriteLine("Mismatched AAD test PASSED (correctly rejected).");
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/* Null info/aad round-trip - exercises the null-marshaling path through P/Invoke */
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Console.WriteLine("Testing HpkeSealBase/OpenBase with null info and aad...");
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byte[] encNull = wolfcrypt.HpkeSealBase(hpke, receiverKey,
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null, null, plaintext, kem);
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if (encNull == null)
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{
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throw new Exception("HpkeSealBase with null info/aad failed");
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}
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byte[] decNull = wolfcrypt.HpkeOpenBase(hpke, receiverKey,
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encNull, null, null, kem);
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if (decNull == null || !wolfcrypt.ByteArrayVerify(plaintext, decNull))
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{
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throw new Exception("HpkeOpenBase with null info/aad: round-trip failed");
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}
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Console.WriteLine("Null info/aad round-trip test PASSED.");
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/* Negative test: invalid ptLen should fail */
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Console.WriteLine("Testing HpkeOpenBase with invalid ptLen...");
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badResult = wolfcrypt.HpkeOpenBase(hpke, receiverKey,
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encCiphertext, info, aad, plaintext.Length + 1);
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if (badResult != null)
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{
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throw new Exception("HpkeOpenBase should fail with incorrect ptLen");
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}
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Console.WriteLine("Invalid ptLen test PASSED (correctly rejected).");
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}
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finally
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{
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/* Cleanup */
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if (ephemeralKey != IntPtr.Zero)
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wolfcrypt.HpkeFreeKey(hpke, ephemeralKey, kem);
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if (deserializedKey != IntPtr.Zero)
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wolfcrypt.HpkeFreeKey(hpke, deserializedKey, kem);
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if (receiverKey != IntPtr.Zero)
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wolfcrypt.HpkeFreeKey(hpke, receiverKey, kem);
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if (hpke != IntPtr.Zero)
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wolfcrypt.HpkeFree(hpke);
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}
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} /* END hpke_test */
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8831079
public static void standard_log(int lvl, StringBuilder msg)
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{
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Console.WriteLine(msg);
@@ -941,6 +1137,15 @@ public static void Main(string[] args)
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hash_test((uint)wolfcrypt.hashType.WC_HASH_TYPE_SHA512); /* SHA-512 HASH test */
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hash_test((uint)wolfcrypt.hashType.WC_HASH_TYPE_SHA3_256); /* SHA3_256 HASH test */
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Console.WriteLine("\nStarting HPKE tests");
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hpke_test(wolfcrypt.HpkeKem.DHKEM_P256_HKDF_SHA256,
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wolfcrypt.HpkeKdf.HKDF_SHA256,
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wolfcrypt.HpkeAead.AES_128_GCM);
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hpke_test(wolfcrypt.HpkeKem.DHKEM_X25519_HKDF_SHA256,
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wolfcrypt.HpkeKdf.HKDF_SHA256,
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wolfcrypt.HpkeAead.AES_128_GCM);
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wolfcrypt.Cleanup();
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Console.WriteLine("\nAll tests completed successfully");

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