49 lines
2.4 KiB
Markdown
49 lines
2.4 KiB
Markdown
# Onionr Protocol Spec v2
|
||
|
||
A P2P platform for Tor & I2P
|
||
|
||
# Overview
|
||
|
||
Onionr is an encrypted microblogging & mailing system designed in the spirit of Twitter.
|
||
There are no central servers and all traffic is peer to peer by default (routed via Tor or I2P).
|
||
User IDs are simply Tor onion service/I2P host id + Ed25519 key fingerprint.
|
||
Private blocks are only able to be read by the intended peer.
|
||
All traffic is over Tor/I2P, connecting only to Tor onion and I2P hidden services.
|
||
|
||
## Goals:
|
||
• Selective sharing of information
|
||
• Secure & semi-anonymous direct messaging
|
||
• Forward secrecy
|
||
• Defense in depth
|
||
• Data should be secure for years to come
|
||
• Decentralization
|
||
* Avoid browser-based exploits that plague similar software
|
||
* Avoid timing attacks & unexpected metadata leaks
|
||
|
||
## Protocol
|
||
|
||
Onionr nodes use HTTP (over Tor/I2P) to exchange keys, metadata, and blocks. Blocks are identified by their sha3_256 hash. Nodes sync a table of blocks hashes and attempt to download blocks they do not yet have from random peers.
|
||
|
||
## Connections
|
||
|
||
When a node first comes online, it attempts to bootstrap using a default list provided by a client.
|
||
When two peers connect, they exchange Ed25519 keys (if applicable) then Salsa20 keys.
|
||
|
||
Salsa20 keys are regenerated either every X many communications with a peer or every X minutes.
|
||
|
||
Every 100kb or every 2 hours is a recommended default.
|
||
|
||
All valid requests with HMAC should be recorded until used HMAC's expiry to prevent replay attacks.
|
||
Peer Types
|
||
* Friends:
|
||
* Encrypted ‘friends only’ posts to one another
|
||
* Usually less strict rate & storage limits
|
||
* Strangers:
|
||
* Used for storage of encrypted or public information
|
||
* Can only read public posts
|
||
* Usually stricter rate & storage limits
|
||
|
||
## Spam mitigation
|
||
|
||
To send or receive data, a node can optionally request that the other node generate a hash that when in hexadecimal representation contains a random string at a random location in the string. Clients will configure what difficulty to request, and what difficulty is acceptable for themselves to perform. Difficulty should correlate with recent network & disk usage and data size. Friends can be configured to have less strict (to non existent) limits, separately from strangers. (proof of work).
|
||
Rate limits can be strict, as Onionr is not intended to be an instant messaging application. |