Module sapling_crypto_ce::jubjub

Jubjub is a twisted Edwards curve defined over the BLS12-381 scalar field, Fr. It takes the form -x^2 + y^2 = 1 + dx^2y^2 with d = -(10240/10241). It is birationally equivalent to a Montgomery curve of the form y^2 = x^3 + Ax^2 + x with A = 40962. This value A is the smallest integer choice such that:

• (A - 2) / 4 is a small integer (10240).
• A^2 - 4 is quadratic nonresidue.
• The group order of the curve and its quadratic twist has a large prime factor.

Jubjub has s = 0x0e7db4ea6533afa906673b0101343b00a6682093ccc81082d0970e5ed6f72cb7 as the prime subgroup order, with cofactor 8. (The twist has cofactor 4.)

It is a complete twisted Edwards curve, so the equivalence with the Montgomery curve forms a group isomorphism, allowing points to be freely converted between the two forms.

Modules

edwards	This is an implementation of the twisted Edwards Jubjub curve.
fs	This is an implementation of the scalar field for Jubjub.
montgomery	This is an implementation of the birationally equivalent Montgomery curve.

Structs

JubjubBls12

Enums

FixedGenerators	Fixed generators of the Jubjub curve of unknown exponent.
PrimeOrder	Point of prime order.
Unknown	Point of unknown order.

Traits

JubjubEngine	This is an extension to the pairing Engine trait which offers a scalar field for the embedded curve (Jubjub) and some pre-computed parameters.
JubjubParams	The pre-computed parameters for Jubjub, including curve constants and various limits and window tables.
ToUniform