From f5ba7a6dc0ddd12173ed072b8579cca25f9ae89e Mon Sep 17 00:00:00 2001 From: Dmitri Bogomolov <4glitch@gmail.com> Date: Tue, 9 Mar 2021 18:45:10 +0200 Subject: [PATCH] Unencrypted Message Data section, msg object type and refs --- docs/protocol.rst | 143 ++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 138 insertions(+), 5 deletions(-) diff --git a/docs/protocol.rst b/docs/protocol.rst index 967ab363..137b1b95 100644 --- a/docs/protocol.rst +++ b/docs/protocol.rst @@ -206,6 +206,103 @@ Bitmessage uses `ECIES = 3**. + * - 1+ + - extra_bytes + - var_int + - Used to calculate the difficulty target of messages accepted by this + node. The higher this value, the more difficult the Proof of Work must + be before this individual will accept the message. This number is added + to the data length to make sending small messages more difficult. + 1000 is the network minimum so any lower values will be automatically + raised to 1000. **This field is new and is only included when the + address_version >= 3**. + * - 20 + - destination ripe + - uchar[] + - The ripe hash of the public key of the receiver of the message + * - 1+ + - encoding + - var_int + - :ref:`Message Encoding ` type + * - 1+ + - message_length + - var_int + - Message Length + * - message_length + - message + - uchar[] + - The message. + * - 1+ + - ack_length + - var_int + - Length of the acknowledgement data + * - ack_length + - ack_data + - uchar[] + - The acknowledgement data to be transmitted. This takes the form of a + Bitmessage protocol message, like another msg message. The POW therein + must already be completed. + * - 1+ + - sig_length + - var_int + - Length of the signature + * - sig_length + - signature + - uchar[] + - The ECDSA signature which covers the object header starting with the + time, appended with the data described in this table down to the + ack_data. + +.. _msg-encodings: Message Encodings """"""""""""""""" @@ -702,6 +799,20 @@ msg Used for person-to-person messages. Note that msg objects won't contain a version in the object header until Sun, 16 Nov 2014 22:00:00 GMT. +.. list-table:: + :header-rows: 1 + :widths: auto + + * - Field Size + - Description + - Data type + - Comments + * - ? + - encrypted + - uchar[] + - Encrypted data. See `Encrypted payload`_. + See also `Unencrypted Message Data`_ + broadcast ^^^^^^^^^ @@ -711,12 +822,34 @@ their inbox. Broadcasts are version 4 or 5. Pubkey objects and v5 broadcast objects are encrypted the same way: The data encoded in the sender's Bitmessage address is hashed twice. The first 32 bytes of the resulting hash constitutes the "private" encryption key and the last -32 bytes constitute a tag so that anyone listening can easily decide if this -particular message is interesting. The sender calculates the public key from -the private key and then encrypts the object with this public key. Thus anyone -who knows the Bitmessage address of the sender of a broadcast or pubkey object -can decrypt it. +32 bytes constitute a **tag** so that anyone listening can easily decide if +this particular message is interesting. The sender calculates the public key +from the private key and then encrypts the object with this public key. Thus +anyone who knows the Bitmessage address of the sender of a broadcast or pubkey +object can decrypt it. The version of broadcast objects was previously 2 or 3 but was changed to 4 or 5 for protocol v3. Having a broadcast version of 5 indicates that a tag is used which, in turn, is used when the sender's address version is >=4. + +.. list-table:: + :header-rows: 1 + :widths: auto + + * - Field Size + - Description + - Data type + - Comments + * - 32 + - tag + - uchar[] + - The tag. This field is new and only included when the broadcast version + is >= 5. Changed in protocol v3 + * - ? + - encrypted + - uchar[] + - Encrypted broadcast data. The keys are derived as described in the + paragraph above. See Encrypted payload for details about the encryption + algorithm itself. + +Unencrypted data format: