lib: crypto: Add AES-256-GCM support

Signed-off-by: Ian Moffett <ian@osmora.org>

1 files changed, 50 insertions, 0 deletions

diff --git a/lib/include/crypto/aes.h b/lib/include/crypto/aes.h
new file mode 100644
index 0000000..5973323
--- /dev/null
+++ b/lib/include/crypto/aes.h
@@ -0,0 +1,50 @@
+/*
+ * Copyright (c) 2023-2024 Ian Marco Moffett and the Osmora Team.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Hyra nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef CRYPTO_AES_H_
+#define CRYPTO_AES_H_
+
+#include <stddef.h>
+
+#define AES_IV_SIZE         16
+#define AES_GCM_TAG_SIZE    16
+
+struct aes_message {
+    unsigned char tag[AES_GCM_TAG_SIZE];
+    unsigned char iv[AES_IV_SIZE];
+    unsigned char *ciphertext;
+    int ciphertext_len;
+};
+
+int aes256_encrypt(const unsigned char *data, size_t len,
+    const unsigned char *key, struct aes_message *res);
+int aes256_decrypt(struct aes_message *amp, const unsigned char *key,
+    unsigned char **res);
+
+#endif  /* CRYPTO_AES_H_ */