Expand description
The field extension whose subfield is order 15*2^27 + 1;
this field choice allows 32-bit addition without overflow
Baby bear field.
Support for the base finite field modulo 15 * 2^27 + 1.
Structs
Definition of this field for operations that operate on the baby
bear field and its 4th degree extension.
The BabyBear class is an element of the finite field F_p, where P is the
prime number 15*2^27 + 1. Put another way, Fp is basically integer
arithmetic modulo P.
Instances of
ExtElem are elements of a finite field F_p^4. They are
represented as elements of F_p[X] / (X^4 + 11). This large
finite field (about 2^128 elements) is used when the security of
operations depends on the size of the field. The field extension ExtElem
has Elem as a subfield, so operations on elements of each are compatible.
The irreducible polynomial x^4 + 11 was chosen because 11 is
the simplest choice of BETA for x^4 + BETA that makes this polynomial
irreducible.