netw0rk

Protocol Outline

T_interval = client authentication time interval (say 24 hours)
T_sigset = The time interval after which a client can reuse the same signature set (say 48 hours)
T_inter = The max time interval after which a peer can sign on a previously provided timestamp (say 15 minutes) [described in Bluetooth Authentication step 5]
n = the number of peers a client needs to receive authentications from

Client establishes connection to a peer via BLE
Peer produces a signature: Sign( ClientPubKey || timestamp ) and transmits it back to the client.
Client collects n such signatures from n peers.
Upon getting S = [S1,S2,...,Sn] such signatures, the client sends S (SigSet) to the last signing peer.
Peers form signature set as follows:
- If the hash, H, of the sorted PeerID list (P = [P1, P2,...Pn]) exists in SigSet Table, do nothing.
- Verify each signature in the set (is valid sig, and belongs to a peer, p ∈ peer_table)
- Verify that max_timestamp(S) - min_timestamp(S) < T_inter
- Concatenate ClientPubKey || P || min_timestamp(S), and sign (call it Ši).
  - ~~Separate by null byte, '\x00' for now~~
- Add client_pub_key, current_timestamp, and H to SigSet_Table
- Send Ši and S to all peers in S.
- After receiving Ši,..., Šn signatures, a peer forms a BLS group signature Š using Ši,..., Šn, and sends Š to client
SigSet_Table

ClientPubKey Timestamp SigSet Peer Hash

1234 1548718597 afh13roidn9

5678 1548703652 grepk1239fnz
- Remove row_i from table if current_timestamp - timestamp_i > n

ClientPubKey	Timestamp	SigSet Peer Hash
1234	1548718597	afh13roidn9
5678	1548703652	grepk1239fnz

~~Packets are only forwarded if BT Auth is valid.~~ Inter-peer communication is unrestricted, that is, peers can forward packets between each other without performing any signature validation.
Entry and Exit peers (the peer who first receives a packet from a client, and the peer who forwards the packet to its destination), are the only ones who perform authentication verification. This includes:
- BT Auth verification, once per session.
- Client Signature verification on every packet
A valid BT Auth:
- signs on UserPubKey who is sending the packet
- is signed by all P
- has current_timestamp - timestamp(SigSet) < T_interval
- for s ∈ SigSet, s(PeerID) ∈ Peer_Table, and s is a valid signature for PeerID
Use CJDNS for forwarding?