diff --git a/src/Mayaqua/Encrypt.c b/src/Mayaqua/Encrypt.c
index 9d2c1a0d..b59ff886 100644
--- a/src/Mayaqua/Encrypt.c
+++ b/src/Mayaqua/Encrypt.c
@@ -570,6 +570,7 @@ CIPHER *NewCipher(char *name)
 	EVP_CIPHER_CTX_init(c->Ctx);
 #endif
 
+	c->IsAeadCipher = EVP_CIPHER_flags(c->Cipher) & EVP_CIPH_FLAG_AEAD_CIPHER;
 	c->BlockSize = EVP_CIPHER_block_size(c->Cipher);
 	c->KeySize = EVP_CIPHER_key_length(c->Cipher);
 	c->IvSize = EVP_CIPHER_iv_length(c->Cipher);
@@ -634,6 +635,74 @@ UINT CipherProcess(CIPHER *c, void *iv, void *dest, void *src, UINT size)
 	return r + r2;
 }
 
+// Process encryption / decryption (AEAD)
+UINT CipherProcessAead(CIPHER *c, void *iv, void *tag, UINT tag_size, void *dest, void *src, UINT src_size, void *aad, UINT aad_size)
+{
+	int r = src_size;
+	int r2 = 0;
+	// Validate arguments
+	if (c == NULL)
+	{
+		return 0;
+	}
+	else if (c->IsNullCipher)
+	{
+		Copy(dest, src, src_size);
+		return src_size;
+	}
+	else if (c->IsAeadCipher == false || iv == NULL || tag == NULL || tag_size == 0 || dest == NULL || src == NULL || src_size == 0)
+	{
+		return 0;
+	}
+
+	if (EVP_CipherInit_ex(c->Ctx, NULL, NULL, NULL, iv, c->Encrypt) == false)
+	{
+		Debug("CipherProcessAead(): EVP_CipherInit_ex() failed with error: %s\n", OpenSSL_Error());
+		return 0;
+	}
+
+	if (c->Encrypt == false)
+	{
+		if (EVP_CIPHER_CTX_ctrl(c->Ctx, EVP_CTRL_AEAD_SET_TAG, tag_size, tag) == false)
+		{
+			Debug("CipherProcessAead(): EVP_CIPHER_CTX_ctrl() failed to set the tag!\n");
+			return 0;
+		}
+	}
+
+	if (aad != NULL && aad_size != 0)
+	{
+		if (EVP_CipherUpdate(c->Ctx, NULL, &r, aad, aad_size) == false)
+		{
+			Debug("CipherProcessAead(): EVP_CipherUpdate() failed with error: %s\n", OpenSSL_Error());
+			return 0;
+		}
+	}
+
+	if (EVP_CipherUpdate(c->Ctx, dest, &r, src, src_size) == false)
+	{
+		Debug("CipherProcessAead(): EVP_CipherUpdate() failed with error: %s\n", OpenSSL_Error());
+		return 0;
+	}
+
+	if (EVP_CipherFinal_ex(c->Ctx, ((UCHAR *)dest) + (UINT)r, &r2) == false)
+	{
+		Debug("CipherProcessAead(): EVP_CipherFinal_ex() failed with error: %s\n", OpenSSL_Error());
+		return 0;
+	}
+
+	if (c->Encrypt)
+	{
+		if (EVP_CIPHER_CTX_ctrl(c->Ctx, EVP_CTRL_AEAD_GET_TAG, tag_size, tag) == false)
+		{
+			Debug("CipherProcessAead(): EVP_CIPHER_CTX_ctrl() failed to get the tag!\n");
+			return 0;
+		}
+	}
+
+	return r + r2;
+}
+
 // Release of the cipher object
 void FreeCipher(CIPHER *c)
 {
diff --git a/src/Mayaqua/Encrypt.h b/src/Mayaqua/Encrypt.h
index 1b2c0ff9..1a9bb468 100644
--- a/src/Mayaqua/Encrypt.h
+++ b/src/Mayaqua/Encrypt.h
@@ -239,6 +239,8 @@ void RAND_Free_For_SoftEther();
 
 // OpenSSL <1.1 Shims
 #if OPENSSL_VERSION_NUMBER < 0x10100000L
+#	define EVP_CTRL_AEAD_GET_TAG EVP_CTRL_GCM_GET_TAG
+#	define EVP_CTRL_AEAD_SET_TAG EVP_CTRL_GCM_SET_TAG
 #	define EVP_PKEY_get0_RSA(obj) ((obj)->pkey.rsa)
 #	define EVP_PKEY_base_id(pkey) ((pkey)->type)
 #	define X509_get0_notBefore(x509) ((x509)->cert_info->validity->notBefore)
@@ -348,7 +350,7 @@ struct DH_CTX
 struct CIPHER
 {
 	char Name[MAX_PATH];
-	bool IsNullCipher;
+	bool IsNullCipher, IsAeadCipher;
 	const struct evp_cipher_st *Cipher;
 	struct evp_cipher_ctx_st *Ctx;
 	bool Encrypt;
@@ -523,6 +525,7 @@ CIPHER *NewCipher(char *name);
 void FreeCipher(CIPHER *c);
 void SetCipherKey(CIPHER *c, void *key, bool enc);
 UINT CipherProcess(CIPHER *c, void *iv, void *dest, void *src, UINT size);
+UINT CipherProcessAead(CIPHER *c, void *iv, void *tag, UINT tag_size, void *dest, void *src, UINT src_size, void *aad, UINT aad_size);
 
 // Hashing
 MD *NewMd(char *name);