|
@@ -0,0 +1,106 @@
|
|
|
|
|
+/*! The various credentials used by the system.
|
|
|
|
|
+
|
|
|
|
|
+In each case, (P,Q) forms the MAC on the credential. This MAC is
|
|
|
|
|
+verifiable only by the issuing party, or if the issuing party issues a
|
|
|
|
|
+zero-knowledge proof of its correctness (as it does at issuing time).*/
|
|
|
|
|
+
|
|
|
|
|
+use curve25519_dalek::ristretto::RistrettoPoint;
|
|
|
|
|
+use curve25519_dalek::scalar::Scalar;
|
|
|
|
|
+use serde::{Deserialize, Serialize};
|
|
|
|
|
+
|
|
|
|
|
+/// A migration credential.
|
|
|
|
|
+///
|
|
|
|
|
+/// This credential authorizes the holder of the Lox credential with the
|
|
|
|
|
+/// given id to switch from bucket from_bucket to bucket to_bucket. The
|
|
|
|
|
+/// migration_type attribute is 0 for trust upgrade migrations (moving
|
|
|
|
|
+/// from a 1-bridge untrusted bucket to a 3-bridge trusted bucket) and 1
|
|
|
|
|
+/// for blockage migrations (moving buckets because the from_bucket has
|
|
|
|
|
+/// been blocked).
|
|
|
|
|
+#[derive(Debug, CMZ, Serialize, Deserialize)]
|
|
|
|
|
+// Annotated to "M"
|
|
|
|
|
+pub struct Migration {
|
|
|
|
|
+ pub P: RistrettoPoint,
|
|
|
|
|
+ pub Q: RistrettoPoint,
|
|
|
|
|
+ pub lox_id: Scalar,
|
|
|
|
|
+ pub from_bucket: Scalar,
|
|
|
|
|
+ pub to_bucket: Scalar,
|
|
|
|
|
+ pub migration_type: Scalar,
|
|
|
|
|
+}
|
|
|
|
|
+
|
|
|
|
|
+/// The main user credential in the Lox system.
|
|
|
|
|
+///
|
|
|
|
|
+/// Its id is jointly generated by the user and the BA (bridge
|
|
|
|
|
+/// authority), but known only to the user. The level_since date is the
|
|
|
|
|
+/// Julian date of when this user was changed to the current trust
|
|
|
|
|
+/// level.
|
|
|
|
|
+#[derive(Debug, CMZ, Serialize, Deserialize)]
|
|
|
|
|
+// Annotated to "L"
|
|
|
|
|
+pub struct Lox {
|
|
|
|
|
+ pub P: RistrettoPoint,
|
|
|
|
|
+ pub Q: RistrettoPoint,
|
|
|
|
|
+ pub id: Scalar,
|
|
|
|
|
+ pub bucket: Scalar,
|
|
|
|
|
+ pub trust_level: Scalar,
|
|
|
|
|
+ pub level_since: Scalar,
|
|
|
|
|
+ pub invites_remaining: Scalar,
|
|
|
|
|
+ pub blockages: Scalar,
|
|
|
|
|
+}
|
|
|
|
|
+
|
|
|
|
|
+/// The migration key credential.
|
|
|
|
|
+///
|
|
|
|
|
+/// This credential is never actually instantiated. It is an implicit
|
|
|
|
|
+/// credential on attributes lox_id and from_bucket. This credential
|
|
|
|
|
+/// type does have an associated private and public key, however. The
|
|
|
|
|
+/// idea is that if a user proves (in zero knowledge) that their Lox
|
|
|
|
|
+/// credential entitles them to migrate from one bucket to another, the
|
|
|
|
|
+/// BA will issue a (blinded, so the BA will not know the values of the
|
|
|
|
|
+/// attributes or of Q) MAC on this implicit credential. The Q value
|
|
|
|
|
+/// will then be used (actually, a hash of lox_id, from_bucket, and Q)
|
|
|
|
|
+/// to encrypt the to_bucket, P, and Q fields of a Migration credential.
|
|
|
|
|
+/// That way, people entitled to migrate buckets can receive a Migration
|
|
|
|
|
+/// credential with their new bucket, without the BA learning either
|
|
|
|
|
+/// their old or new buckets.
|
|
|
|
|
+#[derive(Debug, CMZ, Serialize, Deserialize)]
|
|
|
|
|
+// Annotated to "K"
|
|
|
|
|
+pub struct MigrationKey {
|
|
|
|
|
+ pub P: RistrettoPoint,
|
|
|
|
|
+ pub Q: RistrettoPoint,
|
|
|
|
|
+ pub lox_id: Scalar,
|
|
|
|
|
+ pub from_bucket: Scalar,
|
|
|
|
|
+}
|
|
|
|
|
+
|
|
|
|
|
+/// The Bucket Reachability credential.
|
|
|
|
|
+///
|
|
|
|
|
+/// Each day, a credential of this type is put in each bucket that has
|
|
|
|
|
+/// at least a (configurable) threshold number of bridges that have not
|
|
|
|
|
+/// been blocked as of the given date. Users can present this
|
|
|
|
|
+/// credential (in zero knowledge) with today's date to prove that the
|
|
|
|
|
+/// bridges in their bucket have not been blocked, in order to gain a
|
|
|
|
|
+/// trust level.
|
|
|
|
|
+// Annotated to "B"
|
|
|
|
|
+#[derive(Debug, CMZ, Serialize, Deserialize)]
|
|
|
|
|
+pub struct BucketReachability {
|
|
|
|
|
+ pub P: RistrettoPoint,
|
|
|
|
|
+ pub Q: RistrettoPoint,
|
|
|
|
|
+ pub date: Scalar,
|
|
|
|
|
+ pub bucket: Scalar,
|
|
|
|
|
+}
|
|
|
|
|
+
|
|
|
|
|
+/// The Invitation credential.
|
|
|
|
|
+///
|
|
|
|
|
+/// These credentials allow a Lox user (the inviter) of sufficient trust
|
|
|
|
|
+/// (level 2 or higher) to invite someone else (the invitee) to join the
|
|
|
|
|
+/// system. The invitee ends up at trust level 1, in the _same bucket_
|
|
|
|
|
+/// as the inviter, and inherits the inviter's blockages count (so that
|
|
|
|
|
+/// you can't clear your blockages count simply by inviting yourself).
|
|
|
|
|
+/// Invitations expire after some amount of time.
|
|
|
|
|
+#[derive(Debug, CMZ, Serialize, Deserialize)]
|
|
|
|
|
+// Annotated to "I"
|
|
|
|
|
+pub struct Invitation {
|
|
|
|
|
+ pub P: RistrettoPoint,
|
|
|
|
|
+ pub Q: RistrettoPoint,
|
|
|
|
|
+ pub inv_id: Scalar,
|
|
|
|
|
+ pub date: Scalar,
|
|
|
|
|
+ pub bucket: Scalar,
|
|
|
|
|
+ pub blockages: Scalar,
|
|
|
|
|
+}
|
