Schnorr.verify_p: def of bend-collections-laws-crypto@1.0.0.0
Import: import bend-collections-laws-crypto@1.0.0.0/spec/crypto/secp256k1/schnorr.bend as Schnorr
Lines 82-90 of bend-collections-laws-crypto@1.0.0.0/spec/crypto/secp256k1/schnorr.bend: https://jend.leeeet.dev/read.txt?path=bend-collections-laws-crypto@1.0.0.0/spec/crypto/secp256k1/schnorr.bend&start_line=82&end_line=90

import Base
import bend-collections-laws-crypto@1.0.0.0/spec/crypto/secp256k1/curve.bend as CV

# fail if r >= p or s >= n
def verify_p(+one: Nat, +pk: List<&2, U32>, +m: List<&2, U32>, +sig: List<&2, U32>, mp: Maybe<&2, CV.SPoint>) -> Bool:
  match mp:
    case None{}: False{}
    case Some{+pp}:
      +r = CV.os2ip(CV.first(32n, sig))
      +s = CV.os2ip(CV.after(32n, sig))
      +e = Nat.mod(CV.os2ip(tagged(tag_challenge(), cat(CV.first(32n, sig), cat(pk, m)))), n(one))
      verify_ok(one, r, s, e, pp, Bool.and(Nat.is_lt(r, p(one)), Nat.is_lt(s, n(one))))

Uses (18):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.and
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Maybe
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.is_lt
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.mod
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-crypto@1.0.0.0/spec/crypto/secp256k1/curve.bend&name=SPoint
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-crypto@1.0.0.0/spec/crypto/secp256k1/curve.bend&name=after
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-crypto@1.0.0.0/spec/crypto/secp256k1/curve.bend&name=first
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-crypto@1.0.0.0/spec/crypto/secp256k1/curve.bend&name=os2ip
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-crypto@1.0.0.0/spec/crypto/secp256k1/schnorr.bend&name=cat
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-crypto@1.0.0.0/spec/crypto/secp256k1/schnorr.bend&name=n
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-crypto@1.0.0.0/spec/crypto/secp256k1/schnorr.bend&name=p
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-crypto@1.0.0.0/spec/crypto/secp256k1/schnorr.bend&name=tag_challenge
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-crypto@1.0.0.0/spec/crypto/secp256k1/schnorr.bend&name=tagged
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-crypto@1.0.0.0/spec/crypto/secp256k1/schnorr.bend&name=verify_ok