Crate lox_library

Implementation of a new style of bridge authority for Tor that allows users to invite other users, while protecting the social graph from the bridge authority itself.

We use CMZ14 credentials (GGM version, which is more efficient, but makes a stronger security assumption): “Algebraic MACs and Keyed-Verification Anonymous Credentials” (Chase, Meiklejohn, and Zaverucha, CCS 2014)

The notation follows that of the paper “Hyphae: Social Secret Sharing” (Lovecruft and de Valence, 2017), Section 4.

Modules

bridge_table

The encrypted table of bridges.

bridge_verification_info

cred

The various credentials used by the system.

dup_filter

Filter duplicate shows of credentials and open invitations by id (which will typically be a Scalar).

migration_table

The migration table.

proto

The protocol modules.

Structs

CMZ_A

CMZ_A_TABLE

CMZ_B

CMZ_B_TABLE

IssuerPrivKey

Private Key of the Issuer

IssuerPubKey

Constants

EXPIRY_DATE

MAX_DAILY_BRIDGES

TODO: Decide on maximum daily number of invitations to be distributed

OPENINV_K

Number of times a given invitation is ditributed

OPENINV_LENGTH

An open invitation is a [u8; OPENINV_LENGTH] where the first 32 bytes are the serialization of a random Scalar (the invitation id), the next 4 bytes are a little-endian bucket number, and the last SIGNATURE_LENGTH bytes are the signature on the first 36 bytes.

Functions

pt_dbl

Double a RistrettoPoint

scalar_dbl

Double a Scalar

scalar_u32

Try to extract a u32 from a Scalar

scalar_u64

Try to extract a u64 from a Scalar