Class SM9Pairing

java.lang.Object
org.bouncycastle.math.ec.sm9.SM9Pairing
public class SM9Pairing extends Object
The SM9 R-ate pairing e: G1 x G2 -> G_T over the 256-bit BN curve (GM/T 0044.5-2016). Computed as the optimal-ate/R-ate Miller loop with loop parameter 6t+2, a two-term Frobenius tail, and the final exponentiation f^((q^12-1)/N).

This is a correctness-first reference implementation: the Miller loop runs in F_p12 on the twist image, and the Frobenius/final exponentiation are ordinary F_p12 exponentiations. It is deliberately straightforward, not optimised.

  • Method Summary

    Modifier and Type
    Method
    Description
    static Fp12
    pairing(ECPoint p, SM9G2Point q)
    e(P, Q) for P in G1 (a point of E(F_q)) and Q in G2 (a point of the twist).
    static byte[]
    toBytes(Fp12 z)
    Serialize a G_T element to bytes per GM/T 0044.5: high dimension first, recursively over the 1-2-4-12 tower (w^2, w^1, w^0; then v^1, v^0; then u^1, u^0), 32 bytes per F_q component; 384 bytes total.

    Methods inherited from class Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Method Details

    • pairing

      public static Fp12 pairing(ECPoint p, SM9G2Point q)
      e(P, Q) for P in G1 (a point of E(F_q)) and Q in G2 (a point of the twist).

    • toBytes

      public static byte[] toBytes(Fp12 z)
      Serialize a G_T element to bytes per GM/T 0044.5: high dimension first, recursively over the 1-2-4-12 tower (w^2, w^1, w^0; then v^1, v^0; then u^1, u^0), 32 bytes per F_q component; 384 bytes total.