2.2 KiB
Massive public group chats.
Everyone generates a short term public private key pair right before joining the chat.
Note that for public group chats it is impossible to protect the chat from being spied on by a very dedicated attacker, encryption is therefor used as a form of spam/access control.
Joining the chats
Protocol
Node format:
[char array (node_id), length=32 bytes][ip (in network byte order), length=4 bytes][port (in network byte order), length=2 bytes][Padding , length=2 bytes]
Get nodes (Request): Packet contents:
[char with a value of 48][Bob's (The reciever's) Public key (client_id) (32 bytes))][Alice's (The sender's) Public key (client_id) (32 bytes)][Random nonce (24 bytes)][Encrypted with the nonce and private key of the sender:[char with a value of 48][random 8 byte (ping_id)]
Valid replies: a send_nodes packet
Send_nodes (response):
[char with a value of 48][Bob's (The reciever's) Public key (client_id) (32 bytes))][Alice's (The sender's) Public key (client_id) (32 bytes)][Random nonce (24 bytes)][Encrypted with the nonce and private key of the sender:[char with a value of 49][random 8 byte (ping_id)][Nodes in node format, length=40 * (number of nodes (maximum of 6 nodes)) bytes]]
Broadcast packet:
[char with a value of 48][Bob's (The reciever's) Public key (client_id) (32 bytes))][Alice's (The sender's) Public key (client_id) (32 bytes)][nonce][Encrypted with the nonce and private key of the sender:[char with a value of 50][Data to send to everyone]]
Data to send to everyone: TODO: signing and spam control + permissions. [client_id of sender][uint32_t message number][char with a value representing id of message][data]
Note: the message number is increased by 1 for each sent message.
message ids: 0 - ping sent every ~60 seconds by every peer. No data.
16 - new_peer Tell everyone about a new peer in the chat. [uint8_t public_key[public_key_len]]
17 - ban_peer Ban a peer [uint8_t public_key[public_key_len]]
18 - topic change [uint8_t topic[topiclen]]
48 - name change [uint8_t name[namelen]]
49 - status change [uint8_t (status id)]
64 - chat message [uint8_t message[messagelen]]
65 - action (/me) [uint8_t message[messagelen]]