def pk.len

bend-osdev-pkcs7@0.1.0.0 · PROOF.bend:1332

import Base
import bend-osdev-bytes@0.1.1.0/bytes.bend as B
import bend-osdev-bytes@0.1.1.0/LAWS.bend as BL
import bend-osdev-pkcs7@0.1.0.0/pkcs7.bend as P
import bend-osdev-u32@0.1.0.0/LAWS.bend as UL

1332# the padded message's length
1333def pk.len(+m: B.Octets, +p1: Nat) -> {B.Octets.len(B.Octets.append(m, pk.pad(p1))) == 1n+Nat.add(B.Octets.len(m), p1) : Nat}:
1334  %Equal.sym(Nat, B.Octets.len(B.Octets.append(m, pk.pad(p1))), Nat.add(B.Octets.len(m), B.Octets.len(pk.pad(p1))), BL.octets_len_append(m, pk.pad(p1))) : {_ == 1n+Nat.add(B.Octets.len(m), p1) : Nat}
1335  %Equal.sym(Nat, B.Octets.len(pk.pad(p1)), B.len(P.pkcs7.fill(1n+p1, U32.from_nat(1n+p1))), BL.octets_len_of_list(P.pkcs7.fill(1n+p1, U32.from_nat(1n+p1)))) : {Nat.add(B.Octets.len(m), _) == 1n+Nat.add(B.Octets.len(m), p1) : Nat}
1336  %Equal.sym(Nat, B.len(P.pkcs7.fill(1n+p1, U32.from_nat(1n+p1))), 1n+p1, pk.fill_len(1n+p1, U32.from_nat(1n+p1))) : {Nat.add(B.Octets.len(m), _) == 1n+Nat.add(B.Octets.len(m), p1) : Nat}
1337  UL.nat_add_succ(B.Octets.len(m), p1)