def cbc_rt.xtea

bend-osdev-crypto@0.1.0.0 · PROOF.bend:1509

import Base
import bend-osdev-legacy-ciphers@0.1.0.0/legacy_ciphers.bend as L
import bend-osdev-legacy-ciphers@0.1.0.0/xtea.bend as Xt
import bend-osdev-legacy-ciphers@0.1.0.0/LAWS.bend as LL
import bend-osdev-crypto@0.1.0.0/modes.bend as Md
import bend-osdev-crypto@0.1.0.0/inst_lc.bend as LC

1509def cbc_rt.xtea(+k: Xt.LcXteaKey, bs: List<&2, L.LcBlock64>, +iv: L.LcBlock64) -> {bs == Md.cr.cbc.dec(~Xt.LcXteaKey, ~L.LcBlock64, ~Xt.LcXtea.decrypt, ~LC.CrBlk64.xor, k, Md.cr.cbc.enc(~Xt.LcXteaKey, ~L.LcBlock64, ~Xt.LcXtea.encrypt, ~LC.CrBlk64.xor, k, bs, iv), iv) : List<&2, L.LcBlock64>}:
1510  match bs:
1511    case Nil{}:
1512      {==}
1513    case Con{+p, t}:
1514      %Equal.sym(L.LcBlock64, Xt.LcXtea.decrypt(k, Xt.LcXtea.encrypt(k, LC.CrBlk64.xor(p, iv))), LC.CrBlk64.xor(p, iv), LL.xtea_round_trip(k, LC.CrBlk64.xor(p, iv))) : {Con{p, t} == Con{LC.CrBlk64.xor(_, iv), Md.cr.cbc.dec(~Xt.LcXteaKey, ~L.LcBlock64, ~Xt.LcXtea.decrypt, ~LC.CrBlk64.xor, k, Md.cr.cbc.enc(~Xt.LcXteaKey, ~L.LcBlock64, ~Xt.LcXtea.encrypt, ~LC.CrBlk64.xor, k, t, Xt.LcXtea.encrypt(k, LC.CrBlk64.xor(p, iv))), Xt.LcXtea.encrypt(k, LC.CrBlk64.xor(p, iv)))} : List<&2, L.LcBlock64>}
1515      %lcblock64_xx(p, iv) : {Con{p, t} == Con{_, Md.cr.cbc.dec(~Xt.LcXteaKey, ~L.LcBlock64, ~Xt.LcXtea.decrypt, ~LC.CrBlk64.xor, k, Md.cr.cbc.enc(~Xt.LcXteaKey, ~L.LcBlock64, ~Xt.LcXtea.encrypt, ~LC.CrBlk64.xor, k, t, Xt.LcXtea.encrypt(k, LC.CrBlk64.xor(p, iv))), Xt.LcXtea.encrypt(k, LC.CrBlk64.xor(p, iv)))} : List<&2, L.LcBlock64>}
1516      %cbc_rt.xtea(k, t, Xt.LcXtea.encrypt(k, LC.CrBlk64.xor(p, iv))) : {Con{p, t} == Con{p, _} : List<&2, L.LcBlock64>}
1517      {==}