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permutation fixes

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This commit is contained in:
Mirek Kratochvil 2012-04-08 14:12:16 +02:00
parent 781ea21513
commit 28585ce3f8
1 changed files with 4 additions and 10 deletions
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14
lib/mce.cpp
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@ -19,14 +19,8 @@ int ccr::mce::generate (pubkey&pub, privkey&priv, prng&rng, uint m, uint t)
permutation hp;
priv.g.compute_goppa_check_matrix (priv.h, priv.fld);
int attempts_left = 1 << m;
for (;;) {
if (priv.h.create_goppa_generator (generator, hp, rng) ) break;
--attempts_left;
}
if (!attempts_left) return 1;
hp.compute_inversion (priv.hperm);
for (;;) if (priv.h.create_goppa_generator
(generator, priv.hperm, rng) ) break;
//scramble matrix
matrix S;
@ -79,7 +73,7 @@ int privkey::decrypt (const bvector&in, bvector&out)
permutation hpermInv;
hperm.compute_inversion (hpermInv);
bvector canonical, syndrome;
hperm.permute (not_permuted, canonical);
hpermInv.permute (not_permuted, canonical);
h.mult_vec_right (canonical, syndrome);
//decode
@ -95,7 +89,7 @@ int privkey::decrypt (const bvector&in, bvector&out)
canonical.add (ev);
//shuffle back into systematic order
hpermInv.permute (canonical, not_permuted);
hperm.permute (canonical, not_permuted);
//get rid of redundancy bits
not_permuted.resize (Sinv.size() );