def kb_ctr_prefix

bend-osdev-crypto@0.1.0.0 · PROOF.bend:660

import Base
import bend-osdev-bytes@0.1.0.0/bytes.bend as B
import bend-osdev-crypto@0.1.0.0/kbkdf.bend as Kb

660def kb_ctr_prefix(~K: Data, ~compute: K -> B.Octets -> B.Octets, n: Nat, +j: Nat, cur: List<&2, U32>, +k: K, +rlen: Nat, +fixed: B.Octets, +i: U32) -> {B.take(n, Kb.cr.kb.ctr(~K, ~compute, Nat.add(n, j), cur, k, rlen, fixed, i)) == Kb.cr.kb.ctr(~K, ~compute, n, cur, k, rlen, fixed, i) : List<&2, U32>}:
661  match n:
662    case 0n:
663      {==}
664    case 1n+p:
665      match cur:
666        case Con{h, t}:
667          %kb_ctr_prefix(~K, ~compute, p, j, t, k, rlen, fixed, i) : {Con{h, B.take(p, Kb.cr.kb.ctr(~K, ~compute, Nat.add(p, j), t, k, rlen, fixed, i))} == Con{h, _} : List<&2, U32>}
668          {==}
669        case Nil{}:
670          %kb_ctr_prefix(~K, ~compute, p, j, Kb.cr.kb.tail(B.Octets.to_list(compute(k, B.Octets.append(Kb.CrKbkdf.counter(rlen, U32.add(i, 1)), fixed)))), k, rlen, fixed, U32.add(i, 1)) : {Con{Kb.cr.kb.head(B.Octets.to_list(compute(k, B.Octets.append(Kb.CrKbkdf.counter(rlen, U32.add(i, 1)), fixed)))), B.take(p, Kb.cr.kb.ctr(~K, ~compute, Nat.add(p, j), Kb.cr.kb.tail(B.Octets.to_list(compute(k, B.Octets.append(Kb.CrKbkdf.counter(rlen, U32.add(i, 1)), fixed)))), k, rlen, fixed, U32.add(i, 1)))} == Con{Kb.cr.kb.head(B.Octets.to_list(compute(k, B.Octets.append(Kb.CrKbkdf.counter(rlen, U32.add(i, 1)), fixed)))), _} : List<&2, U32>}
671          {==}