1 files changed, 77 insertions, 42 deletions

diff --git a/src/messenger/messenger_api_message.h b/src/messenger/messenger_api_message.h
index 0f0a97e9c..7ce30dc92 100644
--- a/src/messenger/messenger_api_message.h
+++ b/src/messenger/messenger_api_message.h
@@ -1,6 +1,6 @@
 /*
    This file is part of GNUnet.
-   Copyright (C) 2020 GNUnet e.V.
+   Copyright (C) 2020--2021 GNUnet e.V.
 
    GNUnet is free software: you can redistribute it and/or modify it
    under the terms of the GNU Affero General Public License as published
@@ -36,10 +36,17 @@
 
 #include "messenger_api_ego.h"
 
+#define GNUNET_MESSENGER_MAX_MESSAGE_SIZE (GNUNET_MAX_MESSAGE_SIZE - GNUNET_MIN_MESSAGE_SIZE)
+
+#define GNUNET_MESSENGER_PADDING_MIN (sizeof(uint16_t) + sizeof(char))
+#define GNUNET_MESSENGER_PADDING_LEVEL0 (512)
+#define GNUNET_MESSENGER_PADDING_LEVEL1 (4096)
+#define GNUNET_MESSENGER_PADDING_LEVEL2 (32768)
+
 /**
  * Creates and allocates a new message with a specific <i>kind</i>.
  *
- * @param kind Kind of message
+ * @param[in] kind Kind of message
  * @return New message
  */
 struct GNUNET_MESSENGER_Message*
@@ -48,7 +55,7 @@ create_message (enum GNUNET_MESSENGER_MessageKind kind);
 /**
  * Creates and allocates a copy of a given <i>message</i>.
  *
- * @param message Message
+ * @param[in] message Message
  * @return New message
  */
 struct GNUNET_MESSENGER_Message*
@@ -57,15 +64,24 @@ copy_message (const struct GNUNET_MESSENGER_Message *message);
 /**
  * Destroys a message and frees its memory fully.
  *
- * @param message Message
+ * @param[in/out] message Message
  */
 void
 destroy_message (struct GNUNET_MESSENGER_Message *message);
 
 /**
+ * Returns if the message should be bound to a member session.
+ *
+ * @param[in] message Message
+ * @return #GNUNET_YES or #GNUNET_NO
+ */
+int
+is_message_session_bound (const struct GNUNET_MESSENGER_Message *message);
+
+/**
  * Returns the minimal size in bytes to encode a message of a specific <i>kind</i>.
  *
- * @param kind Kind of message
+ * @param[in] kind Kind of message
  * @return Minimal size to encode
  */
 uint16_t
@@ -74,57 +90,66 @@ get_message_kind_size (enum GNUNET_MESSENGER_MessageKind kind);
 /**
  * Returns the exact size in bytes to encode a given <i>message</i>.
  *
- * @param message Message
+ * @param[in] message Message
+ * @param[in] encode_signature Flag to include signature
  * @return Size to encode
  */
 uint16_t
-get_message_size (const struct GNUNET_MESSENGER_Message *message);
+get_message_size (const struct GNUNET_MESSENGER_Message *message,
+                  int include_signature);
 
 /**
  * Encodes a given <i>message</i> into a <i>buffer</i> of a maximal <i>length</i> in bytes.
  *
- * @param message Message
- * @param length Maximal length to encode
+ * @param[in] message Message
+ * @param[in] length Maximal length to encode
  * @param[out] buffer Buffer
+ * @param[in] encode_signature Flag to include signature
  */
 void
-encode_message (const struct GNUNET_MESSENGER_Message *message, uint16_t length, char *buffer);
+encode_message (const struct GNUNET_MESSENGER_Message *message, uint16_t length, char *buffer,
+                int include_signature);
 
 /**
  * Decodes a <i>message</i> from a given <i>buffer</i> of a maximal <i>length</i> in bytes.
  *
  * If the buffer is too small for a message of its decoded kind the function fails with
- * resulting GNUNET_NO after decoding only the messages header.
+ * resulting #GNUNET_NO after decoding only the messages header.
  *
- * On success the function returns GNUNET_YES.
+ * On success the function returns #GNUNET_YES.
  *
  * @param[out] message Message
- * @param length Maximal length to decode
- * @param buffer Buffer
- * @return GNUNET_YES on success, otherwise GNUNET_NO
+ * @param[in] length Maximal length to decode
+ * @param[in] buffer Buffer
+ * @param[out] padding Padding
+ * @return #GNUNET_YES on success, otherwise #GNUNET_NO
  */
 int
-decode_message (struct GNUNET_MESSENGER_Message *message, uint16_t length, const char *buffer);
+decode_message (struct GNUNET_MESSENGER_Message *message, uint16_t length, const char *buffer,
+                int include_signature, uint16_t *padding);
 
 /**
- * Calculates a <i>hash</i> of a given <i>buffer</i> of a <i>length</i> in bytes.
+ * Calculates a <i>hash</i> of a given <i>buffer</i> with a <i>length</i> in bytes
+ * from a <i>message</i>.
  *
- * @param length Length of buffer
- * @param buffer Buffer
+ * @param[in] message Message
+ * @param[in] length Length of buffer
+ * @param[in] buffer Buffer
  * @param[out] hash Hash
  */
 void
-hash_message (uint16_t length, const char *buffer, struct GNUNET_HashCode *hash);
+hash_message (const struct GNUNET_MESSENGER_Message *message, uint16_t length, const char *buffer,
+              struct GNUNET_HashCode *hash);
 
 /**
  * Signs the <i>hash</i> of a <i>message</i> with a given <i>ego</i> and writes the signature
  * into the <i>buffer</i> as well.
  *
- * @param[out] message Message
- * @param length Length of buffer
+ * @param[in/out] message Message
+ * @param[in] length Length of buffer
  * @param[out] buffer Buffer
- * @param hash Hash of message
- * @param ego EGO
+ * @param[in] hash Hash of message
+ * @param[in] ego EGO
  */
 void
 sign_message (struct GNUNET_MESSENGER_Message *message, uint16_t length, char *buffer,
@@ -132,13 +157,13 @@ sign_message (struct GNUNET_MESSENGER_Message *message, uint16_t length, char *b
 
 /**
  * Verifies the signature of a given <i>message</i> and its <i>hash</i> with a specific
- * public key. The function returns GNUNET_OK if the signature was valid, otherwise
- * GNUNET_SYSERR.
+ * public key. The function returns #GNUNET_OK if the signature was valid, otherwise
+ * #GNUNET_SYSERR.
  *
- * @param message Message
- * @param hash Hash of message
- * @param key Public key of EGO
- * @return GNUNET_OK on success, otherwise GNUNET_SYSERR
+ * @param[in] message Message
+ * @param[in] hash Hash of message
+ * @param[in] key Public key of EGO
+ * @return #GNUNET_OK on success, otherwise #GNUNET_SYSERR
  */
 int
 verify_message (const struct GNUNET_MESSENGER_Message *message, const struct GNUNET_HashCode *hash,
@@ -147,23 +172,23 @@ verify_message (const struct GNUNET_MESSENGER_Message *message, const struct GNU
 /**
  * Encrypts a <i>message</i> using a given public <i>key</i> and replaces its body
  * and kind with the now private encrypted <i>message</i>. The function returns
- * GNUNET_YES if the operation succeeded, otherwise GNUNET_NO.
+ * #GNUNET_YES if the operation succeeded, otherwise #GNUNET_NO.
  *
- * @param message Message
- * @param key Public key of EGO
- * @return GNUNET_YES on success, otherwise GNUNET_NO
+ * @param[in/out] message Message
+ * @param[in] key Public key of EGO
+ * @return #GNUNET_YES on success, otherwise #GNUNET_NO
  */
 int
 encrypt_message (struct GNUNET_MESSENGER_Message *message, const struct GNUNET_IDENTITY_PublicKey *key);
 
 /**
  * Decrypts a private <i>message</i> using a given private <i>key</i> and replaces its body
- * and kind with the inner encrypted message. The function returns GNUNET_YES if the
- * operation succeeded, otherwise GNUNET_NO.
+ * and kind with the inner encrypted message. The function returns #GNUNET_YES if the
+ * operation succeeded, otherwise #GNUNET_NO.
  *
- * @param message Message
- * @param key Private key of EGO
- * @return GNUNET_YES on success, otherwise GNUNET_NO
+ * @param[in/out] message Message
+ * @param[in] key Private key of EGO
+ * @return #GNUNET_YES on success, otherwise #GNUNET_NO
  */
 int
 decrypt_message (struct GNUNET_MESSENGER_Message *message, const struct GNUNET_IDENTITY_PrivateKey *key);
@@ -173,18 +198,28 @@ decrypt_message (struct GNUNET_MESSENGER_Message *message, const struct GNUNET_I
 
 /**
  * Encodes the <i>message</i> to pack it into a newly allocated envelope if <i>mode</i>
- * is equal to GNUNET_MESSENGER_PACK_MODE_ENVELOPE. Independent of the mode the message
+ * is equal to #GNUNET_MESSENGER_PACK_MODE_ENVELOPE. Independent of the mode the message
  * will be hashed if <i>hash</i> is not NULL and it will be signed if the <i>ego</i> is
  * not NULL.
  *
  * @param[out] message Message
  * @param[out] hash Hash of message
- * @param ego EGO to sign
- * @param mode Mode of packing
+ * @param[in] ego EGO to sign
+ * @param[in] mode Mode of packing
  * @return Envelope or NULL
  */
 struct GNUNET_MQ_Envelope*
 pack_message (struct GNUNET_MESSENGER_Message *message, struct GNUNET_HashCode *hash,
               const struct GNUNET_MESSENGER_Ego *ego, int mode);
 
+/**
+ * Returns if a specific kind of message should be sent by a client. The function returns
+ * #GNUNET_YES or #GNUNET_NO for recommendations and #GNUNET_SYSERR for specific kinds
+ * of messages which should not be sent manually at all.
+ *
+ * @param[in] message Message
+ */
+int
+filter_message_sending (const struct GNUNET_MESSENGER_Message *message);
+
 #endif //GNUNET_MESSENGER_API_MESSAGE_H