gdsa: Fix the conversion of hashes to integers to conform to the spec.

[u/mdw/catacomb] / gdsa.c

diff --git a/gdsa.c b/gdsa.c
index 10f6b6d..83f4d06 100644 (file)
--- a/gdsa.c
+++ b/gdsa.c
@@ -79,7 +79,7 @@ void gdsa_endhash(const gdsa *c, ghash *h) { ; }
 void gdsa_sign(const gdsa *c, gdsa_sig *s, const void *m, mp *k)
 {
   group *g = c->g;
-  mp *mr = mp_loadb(MP_NEW, m, c->h->hashsz);
+  mp *mr = dsa_h2n(MP_NEW, g->r, m, c->h->hashsz);
   ge *z = G_CREATE(g);
   mp *sr = s->r, *ss = s->s;
   mpbarrett b;
@@ -128,7 +128,7 @@ int gdsa_verify(const gdsa *c, const gdsa_sig *s, const void *m)
     return (-1);
   mpbarrett_create(&b, g->r); h = mp_modinv(MP_NEW, s->s, g->r);
   e[0].base = g->g; e[1].base = c->p;
-  t = mp_loadb(MP_NEW, m, c->h->hashsz); mp_div(0, &t, t, g->r);
+  t = dsa_h2n(MP_NEW, g->r, m, c->h->hashsz); mp_div(0, &t, t, g->r);
   t = mp_mul(t, t, h); e[0].exp = t = mpbarrett_reduce(&b, t, t);
   h = mp_mul(h, s->r, h); e[1].exp = h = mpbarrett_reduce(&b, h, h);
   w = G_CREATE(g); G_MEXP(g, w, e, 2);