Rc4.rc4.ksa: def of bend-osdev-legacy-ciphers@0.1.0.0
Import: import bend-osdev-legacy-ciphers@0.1.0.0/rc4.bend as Rc4
Lines 81-89 of bend-osdev-legacy-ciphers@0.1.0.0/rc4.bend: https://jend.leeeet.dev/read.txt?path=bend-osdev-legacy-ciphers@0.1.0.0/rc4.bend&start_line=81&end_line=89

import Base
import bend-osdev-legacy-ciphers@0.1.0.0/legacy_ciphers.bend as L

# The key-scheduling algorithm: for i = 0 .. 255,
#   j = j + S[i] + key[i mod keylength]; swap S[i] and S[j]
def rc4.ksa(n: Nat, +key: List<&2, U32>, +klen: Nat, +s: L.LcTab, +i: U32, +j: U32) -> L.LcTab:
  match n:
    case 0n:
      s
    case 1n+p:
      +j2 = U32.and(255, U32.add(U32.add(j, rc4.at(s, i)), L.lc.at(key, Nat.mod(U32.to_nat(i), klen))))
      rc4.ksa(p, key, klen, rc4.swap(s, i, j2), U32.add(i, 1), j2)

Uses (11):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat
  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=Base/base.bend&name=U32.add
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.and
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.to_nat
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-legacy-ciphers@0.1.0.0/legacy_ciphers.bend&name=LcTab
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-legacy-ciphers@0.1.0.0/legacy_ciphers.bend&name=lc.at
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-legacy-ciphers@0.1.0.0/rc4.bend&name=rc4.at
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-legacy-ciphers@0.1.0.0/rc4.bend&name=rc4.swap