def dec_y_rel

bend-collections-laws-crypto@1.0.0.0 · proofs/crypto/ed25519/pdec.bend:148

import Base
import bend-collections-laws-crypto@1.0.0.0/spec/crypto/curve25519/field.bend as FS
import bend-collections-laws-crypto@1.0.0.0/spec/crypto/ed25519.bend as SE
import bend-collections-laws-crypto@1.0.0.0/src/crypto/ed25519/point.bend as PT
import bend-collections-laws-crypto@1.0.0.0/proofs/lib/word.bend as WD
import bend-collections-laws-crypto@1.0.0.0/proofs/crypto/curve25519/limbs.bend as LM
import bend-collections-laws-crypto@1.0.0.0/proofs/crypto/curve25519/rel.bend as RL
import bend-collections-laws-crypto@1.0.0.0/proofs/crypto/ed25519/pcodec.bend as PC

148def dec_y_rel(+one: Nat, +h1: {one == 1n : Nat}, +pp: Nat, +hP: {Nat.add(1n+pp, 19n) == WD.sc(255n, one) : Nat}, +cs: PT.Cs, +D: Nat, +rd: RL.R(pp, PT.cs_d(cs), D), +rs: RL.R(pp, PT.cs_s(cs), SE.sqm1(1n+pp)), +y: List<&2, U32>, +Y: Nat, +hyv: {FS.value(y) == Y : Nat}, +hy: {LM.okb(32n, y, 255n) == True{} : Bool}, +x0: U32, +b0: Nat, +hx0: {v(x0) == b0 : Nat}, +hb0: {Nat.is_le(b0, 1n) == True{} : Bool}, +bad: Bool, +hbad: {PT.ge_p(y) == bad : Bool}, +hlt: {Bool.not(Nat.is_lt(Y, 1n+pp)) == bad : Bool}) -> PC.MR(pp, PT.dec_y(cs, y, x0, PT.ge_p(y)), SE.dec_y(1n+pp, D, Y, b0, bad)):
149  %Equal.sym(Bool, PT.ge_p(y), bad, hbad) : PC.MR(pp, PT.dec_y(cs, y, x0, _), SE.dec_y(1n+pp, D, Y, b0, bad))
150  dec_y_rel_core(one, h1, pp, hP, cs, D, rd, rs, y, Y, hyv, hy, x0, b0, hx0, hb0, bad, hbad, hlt)