Added aead.h header file, forgotten in previous commit.

aead.h

+/* aead.h
+ */
+
+/* nettle, low-level cryptographics library
+ *
+ * Copyright (C) 2014 Niels Möller
+ *
+ * The nettle library is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 of the License, or (at your
+ * option) any later version.
+ *
+ * The nettle library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+ * License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with the nettle library; see the file COPYING.LIB.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02111-1301, USA.
+ */
+
+#ifndef NETTLE_AEAD_H_INCLUDED
+#define NETTLE_AEAD_H_INCLUDED
+
+#include "nettle-types.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Name mangling */
+#define aead_encrypt_msg_size nettle_aead_encrypt_msg_size
+#define aead_encrypt_msg nettle_aead_encrypt_msg
+#define aead_decrypt_msg_size nettle_aead_decrypt_msg_size
+#define aead_decrypt_msg nettle_aead_decrypt_msg
+#define aead_encrypt_ctx_size nettle_aead_encrypt_ctx_size
+#define aead_encrypt_init nettle_aead_encrypt_init
+#define aead_encrypt nettle_aead_encrypt
+#define aead_encrypt_final_size nettle_aead_encrypt_final_size
+#define aead_encrypt_final nettle_aead_encrypt_final
+#define aead_decrypt_ctx_size nettle_aead_decrypt_ctx_size
+#define aead_decrypt_init nettle_aead_decrypt_init
+#define aead_decrypt nettle_aead_decrypt
+#define aead_decrypt_final_size nettle_aead_decrypt_final_size
+#define aead_decrypt_final nettle_aead_decrypt_final
+
+struct nettle_aead;
+struct nettle_buffer;
+
+/* Interface for processing a complete message at a time. Application
+   must allocate the context and call the set_key function before
+   using this interface. */
+size_t
+aead_encrypt_msg_size (const struct nettle_aead *aead, size_t size);
+void
+aead_encrypt_msg (const struct nettle_aead *aead,
+		  void *ctx, const uint8_t *nonce,
+		  size_t ad_size, const uint8_t *ad,
+		  size_t plaintext_size,
+		  uint8_t *gibberish, const uint8_t *plaintext);
+
+size_t
+aead_decrypt_msg_size (const struct nettle_aead *aead, size_t size);
+int
+aead_decrypt_msg (const struct nettle_aead *aead,
+		  void *ctx, const uint8_t *nonce,
+		  size_t ad_size, const uint8_t *ad,
+		  size_t gibberish_size,
+		  uint8_t *plaintext, const uint8_t *gibberish);
+
+/* Streaming interface, including buffering. Uses a context struct
+   corresponding to the aead algorithm, with additional buffers added
+   at the end. Hence, the context can be passed to algorithm-specific
+   functions. Applications should call set_key and set_nonce before
+   using these functions. */
+
+#define aead_update(aead, ctx, size, data) \
+  ((aead)->update((ctx), (size), (data)))
+
+size_t
+aead_encrypt_ctx_size (const struct nettle_aead *aead);
+
+void
+aead_encrypt_init (const struct nettle_aead *aead,
+		   void *ctx, const uint8_t *nonce);
+
+/* Attempts to grow the destination buffer as needed. Returns the
+   amount of plaintext that could be processed. */
+size_t
+aead_encrypt (const struct nettle_aead *aead,
+	      void *ctx, struct nettle_buffer *buffer,
+	      size_t size, const uint8_t *plaintext);
+
+/* Maximum output size for aead_encrypt_final. */
+size_t
+aead_encrypt_final_size (const struct nettle_aead *aead);
+
+/* Returns 1 on success, 0 if buffer was too small and growing it
+   failed. On failure, some output may still be generated, and the
+   function can be called again with more output space. */
+int
+aead_encrypt_final (const struct nettle_aead *aead,
+		    void *ctx, struct nettle_buffer *buffer);
+
+size_t
+aead_decrypt_ctx_size (const struct nettle_aead *aead);
+
+void
+aead_decrypt_init (const struct nettle_aead *aead,
+		   void *ctx, const uint8_t *nonce);
+
+/* Attempts to grow the destination buffer as needed. Returns the
+   amount of plaintext that could be processed. */
+size_t
+aead_decrypt (const struct nettle_aead *aead,
+	      void *ctx, struct nettle_buffer *dst,
+	      size_t size, const uint8_t *gibberish);
+
+/* Maximum output size for aead_decrypt_final. */
+size_t
+aead_decrypt_final_size (const struct nettle_aead *aead);
+
+/* Returns 1 on success, 0 if buffer is too small or authentication
+   failed. FIXME: Distinguish between failure cases? */
+int
+aead_decrypt_final (const struct nettle_aead *aead,
+		    void *ctx, struct nettle_buffer *dst);
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* NETTLE_AEAD_H_INCLUDED */