chiark / gitweb /
catacomb/__init__.py: Don't print secret bits of keys by default.
[catacomb-python] / pubkey.c
index 391db319d4106aef59b02335c4a78c15a2fd18e5..4067ae0ff10219ed5dbff4f24df93be1c4d41af7 100644 (file)
--- a/pubkey.c
+++ b/pubkey.c
@@ -54,26 +54,35 @@ static void dsa_pydealloc(PyObject *me)
 }
 
 static PyObject *dsa_setup(PyTypeObject *ty, PyObject *G, PyObject *u,
-                          PyObject *p, PyObject *rng, PyObject *hash)
+                          PyObject *p, PyObject *rng, PyObject *hash,
+                          void (*calcpub)(group *, ge *, mp *))
 {
   dsa_pyobj *g;
+  ge *pp;
 
   g = PyObject_New(dsa_pyobj, ty);
-  if (GROUP_G(G) != GE_G(p) && !group_samep(GROUP_G(G), GE_G(p)))
-    TYERR("public key not from group");
+  if (p) Py_INCREF(p);
   if (!u) {
     g->d.u = 0;
     u = Py_None;
   } else if ((g->d.u = getmp(u)) == 0)
     goto end;
+  if (!p) {
+    assert(g->d.u); assert(calcpub);
+    pp = G_CREATE(GROUP_G(G));
+    calcpub(GROUP_G(G), pp, g->d.u);
+    p = ge_pywrap(G, pp);
+  } else if (GROUP_G(G) != GE_G(p) && !group_samep(GROUP_G(G), GE_G(p)))
+    TYERR("public key not from group");
   g->d.g = GROUP_G(G);
   g->d.p = GE_X(p);
   g->d.r = GRAND_R(rng);
   g->d.h = GCHASH_CH(hash);
-  g->G = G; Py_INCREF(G); g->u = u; Py_INCREF(u); g->p = p; Py_INCREF(p);
+  g->G = G; Py_INCREF(G); g->u = u; Py_INCREF(u); g->p = p;
   g->rng = rng; Py_INCREF(rng); g->hash = hash; Py_INCREF(hash);
   return ((PyObject *)g);
 end:
+  if (p) Py_DECREF(p);
   FREEOBJ(g);
   return (0);
 }
@@ -81,17 +90,16 @@ end:
 static PyObject *dsapub_pynew(PyTypeObject *ty,
                              PyObject *arg, PyObject *kw)
 {
-  PyObject *G, *p, *u = 0, *rng = rand_pyobj, *hash = sha_pyobj;
+  PyObject *G, *p, *rng = rand_pyobj, *hash = sha_pyobj;
   PyObject *rc = 0;
-  char *kwlist[] = { "G", "p", "u", "hash", "rng", 0 };
+  char *kwlist[] = { "G", "p", "hash", "rng", 0 };
 
-  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O!O!|OO!O!:new", kwlist,
+  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O!O!|O!O!:new", kwlist,
                                   group_pytype, &G,
                                   ge_pytype, &p,
-                                  &u,
                                   gchash_pytype, &hash,
                                   grand_pytype, &rng) ||
-      (rc = dsa_setup(dsapub_pytype, G, u, p, rng, hash)) == 0)
+      (rc = dsa_setup(dsapub_pytype, G, 0, p, rng, hash, 0)) == 0)
     goto end;
 end:
   return (rc);
@@ -156,20 +164,22 @@ end:
   return (rc);
 }
 
+static void dsa_calcpub(group *g, ge *p, mp *u) { G_EXP(g, p, g->g, u); }
+
 static PyObject *dsapriv_pynew(PyTypeObject *ty,
                               PyObject *arg, PyObject *kw)
 {
-  PyObject *G, *p, *u = Py_None, *rng = rand_pyobj, *hash = sha_pyobj;
+  PyObject *G, *p = 0, *u, *rng = rand_pyobj, *hash = sha_pyobj;
   PyObject *rc = 0;
-  char *kwlist[] = { "G", "p", "u", "hash", "rng", 0 };
+  char *kwlist[] = { "G", "u", "p", "hash", "rng", 0 };
 
-  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O!O!O|O!O!:new", kwlist,
+  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O!O|O!O!O!:new", kwlist,
                                   group_pytype, &G,
-                                  ge_pytype, &p,
                                   &u,
+                                  ge_pytype, &p,
                                   gchash_pytype, &hash,
                                   grand_pytype, &rng) ||
-      (rc = dsa_setup(dsapriv_pytype, G, u, p, rng, hash)) == 0)
+      (rc = dsa_setup(dsapriv_pytype, G, u, p, rng, hash, dsa_calcpub)) == 0)
     goto end;
 end:
   return (rc);
@@ -307,36 +317,43 @@ static PyTypeObject dsapriv_pytype_skel = {
 static PyObject *kcdsapub_pynew(PyTypeObject *ty,
                                PyObject *arg, PyObject *kw)
 {
-  PyObject *G, *p, *u = 0, *rng = rand_pyobj, *hash = has160_pyobj;
+  PyObject *G, *p, *rng = rand_pyobj, *hash = has160_pyobj;
   PyObject *rc = 0;
-  char *kwlist[] = { "G", "p", "u", "hash", "rng", 0 };
+  char *kwlist[] = { "G", "p", "hash", "rng", 0 };
 
-  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O!O!O|O!O!:new", kwlist,
+  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O!O!|O!O!:new", kwlist,
                                   group_pytype, &G,
                                   ge_pytype, &p,
-                                  &u,
                                   gchash_pytype, &hash,
                                   grand_pytype, &rng) ||
-      (rc = dsa_setup(kcdsapub_pytype, G, u, p, rng, hash)) == 0)
+      (rc = dsa_setup(kcdsapub_pytype, G, 0, p, rng, hash, 0)) == 0)
     goto end;
 end:
   return (rc);
 }
 
+static void kcdsa_calcpub(group *g, ge *p, mp *u)
+{
+  mp *uinv = mp_modinv(MP_NEW, u, g->r);
+  G_EXP(g, p, g->g, uinv);
+  mp_drop(uinv);
+}
+
 static PyObject *kcdsapriv_pynew(PyTypeObject *ty,
                                 PyObject *arg, PyObject *kw)
 {
-  PyObject *G, *p, *u = Py_None, *rng = rand_pyobj, *hash = has160_pyobj;
+  PyObject *G, *u, *p = 0, *rng = rand_pyobj, *hash = has160_pyobj;
   PyObject *rc = 0;
   char *kwlist[] = { "G", "p", "u", "hash", "rng", 0 };
 
-  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O!O!|OO!O!:new", kwlist,
+  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O!O|O!O!O!:new", kwlist,
                                   group_pytype, &G,
-                                  ge_pytype, &p,
                                   &u,
+                                  ge_pytype, &p,
                                   gchash_pytype, &hash,
                                   grand_pytype, &rng) ||
-      (rc = dsa_setup(kcdsapriv_pytype, G, u, p, rng, hash)) == 0)
+      (rc = dsa_setup(kcdsapriv_pytype, G, u, p,
+                     rng, hash, kcdsa_calcpub)) == 0)
     goto end;
 end:
   return (rc);
@@ -1118,7 +1135,7 @@ end:
   return (rc);
 }
 
-/*----- X25519 ------------------------------------------------------------*/
+/*----- X25519 and related algorithms -------------------------------------*/
 
 static PyObject *meth_x25519(PyObject *me, PyObject *arg)
 {
@@ -1136,6 +1153,22 @@ end:
   return (0);
 }
 
+static PyObject *meth_x448(PyObject *me, PyObject *arg)
+{
+  const char *k, *p;
+  Py_ssize_t ksz, psz;
+  PyObject *rc = 0;
+  if (!PyArg_ParseTuple(arg, "s#s#:x448", &k, &ksz, &p, &psz)) goto end;
+  if (ksz != X448_KEYSZ) VALERR("bad key length");
+  if (psz != X448_PUBSZ) VALERR("bad public length");
+  rc = bytestring_pywrap(0, X448_OUTSZ);
+  x448((octet *)PyString_AS_STRING(rc),
+       (const octet *)k, (const octet *)p);
+  return (rc);
+end:
+  return (0);
+}
+
 /*----- Ed25519 -----------------------------------------------------------*/
 
 static PyObject *meth_ed25519_pubkey(PyObject *me, PyObject *arg)
@@ -1203,6 +1236,8 @@ static PyMethodDef methods[] = {
 generate(NBITS, [event = pgen_nullev, rng = rand, nsteps = 0]) -> R")
   METH  (x25519,                       "\
 x25519(KEY, PUBLIC) -> SHARED")
+  METH  (x448,                         "\
+x448(KEY, PUBLIC) -> SHARED")
   METH  (ed25519_pubkey,               "\
 ed25519_pubkey(KEY) -> PUBLIC")
   KWMETH(ed25519_sign,                 "\