[catacomb-python] / pubkey.c

/* -*-c-*-
 *
 * Public-key cryptography
 *
 * (c) 2004 Straylight/Edgeware
 */

/*----- Licensing notice --------------------------------------------------*
 *
 * This file is part of the Python interface to Catacomb.
 *
 * Catacomb/Python is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * Catacomb/Python is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Catacomb/Python; if not, write to the Free Software Foundation,
 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

/*----- Header files ------------------------------------------------------*/

#include "catacomb-python.h"

/*----- DSA and similar ---------------------------------------------------*/

typedef struct dsa_pyobj {
  PyObject_HEAD
  PyObject *G, *u, *p, *rng, *hash;
  gdsa d;
} dsa_pyobj;

static PyTypeObject *dsapub_pytype, *dsapriv_pytype;
static PyTypeObject *kcdsapub_pytype, *kcdsapriv_pytype;
#define DSA_D(o) (&((dsa_pyobj *)(o))->d)
#define DSA_G(o) (((dsa_pyobj *)(o))->G)
#define DSA_U(o) (((dsa_pyobj *)(o))->u)
#define DSA_P(o) (((dsa_pyobj *)(o))->p)
#define DSA_RNG(o) (((dsa_pyobj *)(o))->rng)
#define DSA_HASH(o) (((dsa_pyobj *)(o))->hash)

static void dsa_pydealloc(PyObject *me)
{
  dsa_pyobj *g = (dsa_pyobj *)me;
  Py_DECREF(g->G); Py_DECREF(g->u); Py_DECREF(g->p);
  Py_DECREF(g->rng); Py_DECREF(g->hash);
  FREEOBJ(me);
}

static PyObject *dsa_setup(PyTypeObject *ty, PyObject *G, PyObject *u,
			   PyObject *p, PyObject *rng, PyObject *hash)
{
  dsa_pyobj *g;

  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 (!u) {
    g->d.u = 0;
    u = Py_None;
  } else if ((g->d.u = getmp(u)) == 0)
    goto end;
  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->rng = rng; Py_INCREF(rng); g->hash = hash; Py_INCREF(hash);
  return ((PyObject *)g);
end:
  FREEOBJ(g);
  return (0);
}

static PyObject *dsapub_pynew(PyTypeObject *ty,
			      PyObject *arg, PyObject *kw)
{
  PyObject *G, *p, *u = 0, *rng = rand_pyobj, *hash = sha_pyobj;
  PyObject *rc = 0;
  char *kwlist[] = { "G", "p", "u", "hash", "rng", 0 };

  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O!O!|OO!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)
    goto end;
end:
  return (rc);
}

static PyObject *dsameth_beginhash(PyObject *me, PyObject *arg)
{
  if (!PyArg_ParseTuple(arg, ":beginhash")) return (0);
  return (ghash_pywrap(DSA_HASH(me), gdsa_beginhash(DSA_D(me)), f_freeme));
}

static PyObject *dsameth_endhash(PyObject *me, PyObject *arg)
{
  ghash *h;
  PyObject *rc;
  if (!PyArg_ParseTuple(arg, "O&:endhash", convghash, &h)) return (0);
  gdsa_endhash(DSA_D(me), h);
  h = GH_COPY(h);
  rc = bytestring_pywrap(0, GH_CLASS(h)->hashsz);
  GH_DONE(h, PyString_AS_STRING(rc));
  GH_DESTROY(h);
  return (rc);
}

static PyObject *dsameth_sign(PyObject *me, PyObject *arg, PyObject *kw)
{
  gdsa_sig s = GDSA_SIG_INIT;
  char *p;
  int n;
  mp *k = 0;
  PyObject *rc = 0;
  char *kwlist[] = { "msg", "k", 0 };

  if (!PyArg_ParseTupleAndKeywords(arg, kw, "s#|O&:sign", kwlist,
				   &p, &n, convmp, &k))
    goto end;
  if (n != DSA_D(me)->h->hashsz)
    VALERR("bad message length (doesn't match hash size)");
  gdsa_sign(DSA_D(me), &s, p, k);
  rc = Py_BuildValue("(NN)", mp_pywrap(s.r), mp_pywrap(s.s));
end:
  mp_drop(k);
  return (rc);
}

static PyObject *dsameth_verify(PyObject *me, PyObject *arg)
{
  char *p;
  int n;
  gdsa_sig s = GDSA_SIG_INIT;
  PyObject *rc = 0;

  if (!PyArg_ParseTuple(arg, "s#(O&O&):verify",
			&p, &n, convmp, &s.r, convmp, &s.s))
    goto end;
  if (n != DSA_D(me)->h->hashsz)
    VALERR("bad message length (doesn't match hash size)");
  rc = getbool(!gdsa_verify(DSA_D(me), &s, p));
end:
  mp_drop(s.r);
  mp_drop(s.s);
  return (rc);
}

static PyObject *dsapriv_pynew(PyTypeObject *ty,
			       PyObject *arg, PyObject *kw)
{
  PyObject *G, *p, *u = Py_None, *rng = rand_pyobj, *hash = sha_pyobj;
  PyObject *rc = 0;
  char *kwlist[] = { "G", "p", "u", "hash", "rng", 0 };

  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O!O!O|O!O!:new", kwlist,
				   group_pytype, &G,
				   ge_pytype, &p,
				   &u,
				   gchash_pytype, &hash,
				   grand_pytype, &rng) ||
      (rc = dsa_setup(dsapriv_pytype, G, u, p, rng, hash)) == 0)
    goto end;
end:
  return (rc);
}

static PyMethodDef dsapub_pymethods[] = {
#define METHNAME(name) dsameth_##name
  METH	(beginhash,		"D.beginhash() -> hash object")
  METH	(endhash,		"D.endhash(H) -> BYTES")
  METH	(verify,		"D.verify(MSG, (R, S)) -> true/false")
#undef METHNAME
  { 0 }
};

static PyMethodDef dsapriv_pymethods[] = {
#define METHNAME(name) dsameth_##name
  KWMETH(sign,			"D.sign(MSG, k = K) -> R, S")
#undef METHNAME
  { 0 }
};

static PyMemberDef dsapub_pymembers[] = {
#define MEMBERSTRUCT dsa_pyobj
  MEMBER(G,	T_OBJECT, READONLY, "D.G -> group to work in")
  MEMBER(p,	T_OBJECT, READONLY, "D.p -> public key (group element")
  MEMBER(rng,	T_OBJECT, READONLY, "D.rng -> random number generator")
  MEMBER(hash,	T_OBJECT, READONLY, "D.hash -> hash class")
#undef MEMBERSTRUCT
  { 0 }
};

static PyMemberDef dsapriv_pymembers[] = {
#define MEMBERSTRUCT dsa_pyobj
  MEMBER(u,	T_OBJECT, READONLY, "D.u -> private key (exponent)")
#undef MEMBERSTRUCT
  { 0 }
};

static PyTypeObject dsapub_pytype_skel = {
  PyObject_HEAD_INIT(0) 0,		/* Header */
  "DSAPub",				/* @tp_name@ */
  sizeof(dsa_pyobj),			/* @tp_basicsize@ */
  0,					/* @tp_itemsize@ */

  dsa_pydealloc,			/* @tp_dealloc@ */
  0,					/* @tp_print@ */
  0,					/* @tp_getattr@ */
  0,					/* @tp_setattr@ */
  0,					/* @tp_compare@ */
  0,					/* @tp_repr@ */
  0,					/* @tp_as_number@ */
  0,					/* @tp_as_sequence@ */
  0,					/* @tp_as_mapping@ */
  0,					/* @tp_hash@ */
  0,					/* @tp_call@ */
  0,					/* @tp_str@ */
  0,					/* @tp_getattro@ */
  0,					/* @tp_setattro@ */
  0,					/* @tp_as_buffer@ */
  Py_TPFLAGS_DEFAULT |			/* @tp_flags@ */
    Py_TPFLAGS_BASETYPE,

  /* @tp_doc@ */
"DSA public key information.",

  0,					/* @tp_traverse@ */
  0,					/* @tp_clear@ */
  0,					/* @tp_richcompare@ */
  0,					/* @tp_weaklistoffset@ */
  0,					/* @tp_iter@ */
  0,					/* @tp_iternext@ */
  dsapub_pymethods,			/* @tp_methods@ */
  dsapub_pymembers,			/* @tp_members@ */
  0,					/* @tp_getset@ */
  0,					/* @tp_base@ */
  0,					/* @tp_dict@ */
  0,					/* @tp_descr_get@ */
  0,					/* @tp_descr_set@ */
  0,					/* @tp_dictoffset@ */
  0,					/* @tp_init@ */
  PyType_GenericAlloc,			/* @tp_alloc@ */
  dsapub_pynew,				/* @tp_new@ */
  0,					/* @tp_free@ */
  0					/* @tp_is_gc@ */
};

static PyTypeObject dsapriv_pytype_skel = {
  PyObject_HEAD_INIT(0) 0,		/* Header */
  "DSAPriv",				/* @tp_name@ */
  sizeof(dsa_pyobj),			/* @tp_basicsize@ */
  0,					/* @tp_itemsize@ */

  0,					/* @tp_dealloc@ */
  0,					/* @tp_print@ */
  0,					/* @tp_getattr@ */
  0,					/* @tp_setattr@ */
  0,					/* @tp_compare@ */
  0,					/* @tp_repr@ */
  0,					/* @tp_as_number@ */
  0,					/* @tp_as_sequence@ */
  0,					/* @tp_as_mapping@ */
  0,					/* @tp_hash@ */
  0,					/* @tp_call@ */
  0,					/* @tp_str@ */
  0,					/* @tp_getattro@ */
  0,					/* @tp_setattro@ */
  0,					/* @tp_as_buffer@ */
  Py_TPFLAGS_DEFAULT |			/* @tp_flags@ */
    Py_TPFLAGS_BASETYPE,

  /* @tp_doc@ */
"DSA private key information.",

  0,					/* @tp_traverse@ */
  0,					/* @tp_clear@ */
  0,					/* @tp_richcompare@ */
  0,					/* @tp_weaklistoffset@ */
  0,					/* @tp_iter@ */
  0,					/* @tp_iternext@ */
  dsapriv_pymethods,			/* @tp_methods@ */
  dsapriv_pymembers,			/* @tp_members@ */
  0,					/* @tp_getset@ */
  0,					/* @tp_base@ */
  0,					/* @tp_dict@ */
  0,					/* @tp_descr_get@ */
  0,					/* @tp_descr_set@ */
  0,					/* @tp_dictoffset@ */
  0,					/* @tp_init@ */
  PyType_GenericAlloc,			/* @tp_alloc@ */
  dsapriv_pynew,			/* @tp_new@ */
  0,					/* @tp_free@ */
  0					/* @tp_is_gc@ */
};

static PyObject *kcdsapub_pynew(PyTypeObject *ty,
				PyObject *arg, PyObject *kw)
{
  PyObject *G, *p, *u = 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!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)
    goto end;
end:
  return (rc);
}

static PyObject *kcdsapriv_pynew(PyTypeObject *ty,
				 PyObject *arg, PyObject *kw)
{
  PyObject *G, *p, *u = Py_None, *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,
				   group_pytype, &G,
				   ge_pytype, &p,
				   &u,
				   gchash_pytype, &hash,
				   grand_pytype, &rng) ||
      (rc = dsa_setup(kcdsapriv_pytype, G, u, p, rng, hash)) == 0)
    goto end;
end:
  return (rc);
}

static PyObject *kcdsameth_beginhash(PyObject *me, PyObject *arg)
{
  if (!PyArg_ParseTuple(arg, ":beginhash")) return (0);
  return (ghash_pywrap(DSA_HASH(me), gkcdsa_beginhash(DSA_D(me)), f_freeme));
}

static PyObject *kcdsameth_endhash(PyObject *me, PyObject *arg)
{
  ghash *h;
  PyObject *rc;
  if (!PyArg_ParseTuple(arg, "O&:endhash", convghash, &h)) return (0);
  gkcdsa_endhash(DSA_D(me), h);
  h = GH_COPY(h);
  rc = bytestring_pywrap(0, GH_CLASS(h)->hashsz);
  GH_DONE(h, PyString_AS_STRING(rc));
  GH_DESTROY(h);
  return (rc);
}

static PyObject *kcdsameth_sign(PyObject *me, PyObject *arg, PyObject *kw)
{
  gkcdsa_sig s = GKCDSA_SIG_INIT;
  char *p;
  int n;
  mp *k = 0;
  PyObject *r = 0, *rc = 0;
  char *kwlist[] = { "msg", "k", 0 };

  if (!PyArg_ParseTupleAndKeywords(arg, kw, "s#|O&:sign", kwlist,
				   &p, &n, convmp, &k))
    goto end;
  if (n != DSA_D(me)->h->hashsz)
    VALERR("bad message length (doesn't match hash size)");
  r = bytestring_pywrap(0, DSA_D(me)->h->hashsz);
  s.r = (octet *)PyString_AS_STRING(r);
  gkcdsa_sign(DSA_D(me), &s, p, k);
  rc = Py_BuildValue("(ON)", r, mp_pywrap(s.s));
end:
  Py_XDECREF(r);
  mp_drop(k);
  return (rc);
}

static PyObject *kcdsameth_verify(PyObject *me, PyObject *arg)
{
  char *p;
  int n, rn;
  gkcdsa_sig s = GKCDSA_SIG_INIT;
  PyObject *rc = 0;

  if (!PyArg_ParseTuple(arg, "s#(s#O&):verify",
			&p, &n, &s.r, &rn, convmp, &s.s))
    goto end;
  if (n != DSA_D(me)->h->hashsz)
    VALERR("bad message length (doesn't match hash size)");
  if (rn != DSA_D(me)->h->hashsz)
    VALERR("bad signature `r' length (doesn't match hash size)");
  rc = getbool(!gkcdsa_verify(DSA_D(me), &s, p));
end:
  mp_drop(s.s);
  return (rc);
}

static PyMethodDef kcdsapub_pymethods[] = {
#define METHNAME(name) kcdsameth_##name
  METH	(beginhash,		"D.beginhash() -> hash object")
  METH	(endhash,		"D.endhash(H) -> BYTES")
  METH	(verify,		"D.verify(MSG, (R, S)) -> true/false")
#undef METHNAME
  { 0 }
};

static PyMethodDef kcdsapriv_pymethods[] = {
#define METHNAME(name) kcdsameth_##name
  KWMETH(sign,			"D.sign(MSG, k = K) -> R, S")
#undef METHNAME
  { 0 }
};

static PyTypeObject kcdsapub_pytype_skel = {
  PyObject_HEAD_INIT(0) 0,		/* Header */
  "KCDSAPub",				/* @tp_name@ */
  sizeof(dsa_pyobj),			/* @tp_basicsize@ */
  0,					/* @tp_itemsize@ */

  dsa_pydealloc,			/* @tp_dealloc@ */
  0,					/* @tp_print@ */
  0,					/* @tp_getattr@ */
  0,					/* @tp_setattr@ */
  0,					/* @tp_compare@ */
  0,					/* @tp_repr@ */
  0,					/* @tp_as_number@ */
  0,					/* @tp_as_sequence@ */
  0,					/* @tp_as_mapping@ */
  0,					/* @tp_hash@ */
  0,					/* @tp_call@ */
  0,					/* @tp_str@ */
  0,					/* @tp_getattro@ */
  0,					/* @tp_setattro@ */
  0,					/* @tp_as_buffer@ */
  Py_TPFLAGS_DEFAULT |			/* @tp_flags@ */
    Py_TPFLAGS_BASETYPE,

  /* @tp_doc@ */
"KCDSA public key information.",

  0,					/* @tp_traverse@ */
  0,					/* @tp_clear@ */
  0,					/* @tp_richcompare@ */
  0,					/* @tp_weaklistoffset@ */
  0,					/* @tp_iter@ */
  0,					/* @tp_iternext@ */
  kcdsapub_pymethods,			/* @tp_methods@ */
  dsapub_pymembers,			/* @tp_members@ */
  0,					/* @tp_getset@ */
  0,					/* @tp_base@ */
  0,					/* @tp_dict@ */
  0,					/* @tp_descr_get@ */
  0,					/* @tp_descr_set@ */
  0,					/* @tp_dictoffset@ */
  0,					/* @tp_init@ */
  PyType_GenericAlloc,			/* @tp_alloc@ */
  kcdsapub_pynew,			/* @tp_new@ */
  0,					/* @tp_free@ */
  0					/* @tp_is_gc@ */
};

static PyTypeObject kcdsapriv_pytype_skel = {
  PyObject_HEAD_INIT(0) 0,		/* Header */
  "KCDSAPriv",				/* @tp_name@ */
  sizeof(dsa_pyobj),			/* @tp_basicsize@ */
  0,					/* @tp_itemsize@ */

  0,					/* @tp_dealloc@ */
  0,					/* @tp_print@ */
  0,					/* @tp_getattr@ */
  0,					/* @tp_setattr@ */
  0,					/* @tp_compare@ */
  0,					/* @tp_repr@ */
  0,					/* @tp_as_number@ */
  0,					/* @tp_as_sequence@ */
  0,					/* @tp_as_mapping@ */
  0,					/* @tp_hash@ */
  0,					/* @tp_call@ */
  0,					/* @tp_str@ */
  0,					/* @tp_getattro@ */
  0,					/* @tp_setattro@ */
  0,					/* @tp_as_buffer@ */
  Py_TPFLAGS_DEFAULT |			/* @tp_flags@ */
    Py_TPFLAGS_BASETYPE,

  /* @tp_doc@ */
"KCDSA private key information.",

  0,					/* @tp_traverse@ */
  0,					/* @tp_clear@ */
  0,					/* @tp_richcompare@ */
  0,					/* @tp_weaklistoffset@ */
  0,					/* @tp_iter@ */
  0,					/* @tp_iternext@ */
  kcdsapriv_pymethods,			/* @tp_methods@ */
  dsapriv_pymembers,			/* @tp_members@ */
  0,					/* @tp_getset@ */
  0,					/* @tp_base@ */
  0,					/* @tp_dict@ */
  0,					/* @tp_descr_get@ */
  0,					/* @tp_descr_set@ */
  0,					/* @tp_dictoffset@ */
  0,					/* @tp_init@ */
  PyType_GenericAlloc,			/* @tp_alloc@ */
  kcdsapriv_pynew,			/* @tp_new@ */
  0,					/* @tp_free@ */
  0					/* @tp_is_gc@ */
};

/*----- RSA ---------------------------------------------------------------*/

typedef struct rsapub_pyobj {
  PyObject_HEAD
  rsa_pub pub;
  rsa_pubctx pubctx;
} rsapub_pyobj;

#define RSA_PUB(o) (&((rsapub_pyobj *)(o))->pub)
#define RSA_PUBCTX(o) (&((rsapub_pyobj *)(o))->pubctx)

typedef struct rsapriv_pyobj {
  PyObject_HEAD
  rsa_pub pub;
  rsa_pubctx pubctx;
  rsa_priv priv;
  rsa_privctx privctx;
  PyObject *rng;
} rsapriv_pyobj;

#define RSA_PRIV(o) (&((rsapriv_pyobj *)(o))->priv)
#define RSA_PRIVCTX(o) (&((rsapriv_pyobj *)(o))->privctx)
#define RSA_RNG(o) (((rsapriv_pyobj *)(o))->rng)

static PyTypeObject *rsapub_pytype, *rsapriv_pytype;

static PyObject *rsapub_pynew(PyTypeObject *ty,
			      PyObject *arg, PyObject *kw)
{
  rsa_pub rp = { 0 };
  rsapub_pyobj *o;
  char *kwlist[] = { "n", "e", 0 };

  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O&O&:new", kwlist,
				   convmp, &rp.n, convmp, &rp.e))
    goto end;
  if (!MP_ODDP(rp.n)) VALERR("RSA modulus must be even");
  o = (rsapub_pyobj *)ty->tp_alloc(ty, 0);
  o->pub = rp;
  rsa_pubcreate(&o->pubctx, &o->pub);
  return ((PyObject *)o);
end:
  rsa_pubfree(&rp);
  return (0);
}

static void rsapub_pydealloc(PyObject *me)
{
  rsa_pubdestroy(RSA_PUBCTX(me));
  rsa_pubfree(RSA_PUB(me));
  FREEOBJ(me);
}

static PyObject *rsaget_n(PyObject *me, void *hunoz)
  { return mp_pywrap(MP_COPY(RSA_PUB(me)->n)); }

static PyObject *rsaget_e(PyObject *me, void *hunoz)
  { return mp_pywrap(MP_COPY(RSA_PUB(me)->e)); }

static PyObject *rsameth_pubop(PyObject *me, PyObject *arg)
{
  mp *x = 0;
  PyObject *rc = 0;

  if (!PyArg_ParseTuple(arg, "O&:pubop", convmp, &x)) goto end;
  rc = mp_pywrap(rsa_pubop(RSA_PUBCTX(me), MP_NEW, x));
end:
  mp_drop(x);
  return (rc);
}

static PyObject *rsapriv_dopywrap(PyTypeObject *ty,
				  rsa_priv *rp, PyObject *rng)
{
  rsapriv_pyobj *o;

  o = (rsapriv_pyobj *)ty->tp_alloc(ty, 0);
  o->priv = *rp;
  o->pub.n = rp->n;
  o->pub.e = rp->e;
  rsa_privcreate(&o->privctx, &o->priv, &rand_global);
  rsa_pubcreate(&o->pubctx, &o->pub);
  if (!rng) {
    rng = Py_None;
    Py_INCREF(rng);
  }
  o->rng = rng;
  return ((PyObject *)o);
}

PyObject *rsapriv_pywrap(rsa_priv *rp)
  { return rsapriv_dopywrap(rsapriv_pytype, rp, 0); }

static PyObject *rsapriv_pynew(PyTypeObject *ty,
			       PyObject *arg, PyObject *kw)
{
  rsa_priv rp = { 0 };
  PyObject *rng = Py_None;
  char *kwlist[] =
    { "n", "e", "d", "p", "q", "dp", "dq", "q_inv", "rng", 0 };

  if (!PyArg_ParseTupleAndKeywords(arg, kw, "|O&O&O&O&O&O&O&O&O:new", kwlist,
				   convmp, &rp.n, convmp, &rp.e,
				   convmp, &rp.d,
				   convmp, &rp.p, convmp, &rp.q,
				   convmp, &rp.dp, convmp, &rp.dq,
				   convmp, &rp.q_inv,
				   &rng))
    goto end;
  if ((rp.n && !MP_ODDP(rp.n)) ||
      (rp.p && !MP_ODDP(rp.p)) ||
      (rp.p && !MP_ODDP(rp.q)))
    VALERR("RSA modulus and factors must be odd");
  if (rsa_recover(&rp)) VALERR("couldn't construct private key");
  if (rng != Py_None && !GRAND_PYCHECK(rng))
    TYERR("not a random number source");
  Py_INCREF(rng);
  return (rsapriv_dopywrap(ty, &rp, rng));
end:
  rsa_privfree(&rp);
  return (0);
}

static void rsapriv_pydealloc(PyObject *me)
{
  RSA_PRIVCTX(me)->r = &rand_global;
  rsa_privdestroy(RSA_PRIVCTX(me));
  rsa_privfree(RSA_PRIV(me));
  Py_DECREF(RSA_RNG(me));
  FREEOBJ(me);
}

static PyObject *rsaget_d(PyObject *me, void *hunoz)
  { return mp_pywrap(MP_COPY(RSA_PRIV(me)->d)); }

static PyObject *rsaget_p(PyObject *me, void *hunoz)
  { return mp_pywrap(MP_COPY(RSA_PRIV(me)->p)); }

static PyObject *rsaget_q(PyObject *me, void *hunoz)
  { return mp_pywrap(MP_COPY(RSA_PRIV(me)->q)); }

static PyObject *rsaget_dp(PyObject *me, void *hunoz)
  { return mp_pywrap(MP_COPY(RSA_PRIV(me)->dp)); }

static PyObject *rsaget_dq(PyObject *me, void *hunoz)
  { return mp_pywrap(MP_COPY(RSA_PRIV(me)->dq)); }

static PyObject *rsaget_q_inv(PyObject *me, void *hunoz)
  { return mp_pywrap(MP_COPY(RSA_PRIV(me)->q_inv)); }

static PyObject *rsaget_rng(PyObject *me, void *hunoz)
  { RETURN_OBJ(RSA_RNG(me)); }

static int rsaset_rng(PyObject *me, PyObject *val, void *hunoz)
{
  int rc = -1;
  if (!val)
    val = Py_None;
  else if (val != Py_None && !GRAND_PYCHECK(val))
    TYERR("expected grand or None");
  Py_DECREF(RSA_RNG(me));
  RSA_RNG(me) = val;
  Py_INCREF(val);
  rc = 0;
end:
  return (rc);
}

static PyObject *rsameth_privop(PyObject *me, PyObject *arg, PyObject *kw)
{
  PyObject *rng = RSA_RNG(me);
  mp *x = 0;
  PyObject *rc = 0;
  char *kwlist[] = { "x", "rng", 0 };

  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O&|O:privop", kwlist,
				   convmp, &x, &rng))
    goto end;
  if (rng != Py_None && !GRAND_PYCHECK(rng))
    TYERR("not a random number source");
  RSA_PRIVCTX(me)->r = (rng == Py_None) ? 0 : GRAND_R(rng);
  rc = mp_pywrap(rsa_privop(RSA_PRIVCTX(me), MP_NEW, x));
end:
  mp_drop(x);
  return (rc);
}

static PyObject *meth__RSAPriv_generate(PyObject *me,
					PyObject *arg, PyObject *kw)
{
  grand *r = &rand_global;
  unsigned nbits;
  unsigned n = 0;
  rsa_priv rp;
  pgev evt = { 0 };
  char *kwlist[] = { "class", "nbits", "event", "rng", "nsteps", 0 };
  PyObject *rc = 0;

  if (!PyArg_ParseTupleAndKeywords(arg, kw, "OO&|O&O&O&:generate", kwlist,
				   &me, convuint, &nbits, convpgev, &evt,
				   convgrand, &r, convuint, &n))
    goto end;
  if (rsa_gen(&rp, nbits, r, n, evt.proc, evt.ctx))
    PGENERR;
  rc = rsapriv_pywrap(&rp);
end:
  droppgev(&evt);
  return (rc);
}

static PyGetSetDef rsapub_pygetset[] = {
#define GETSETNAME(op, name) rsa##op##_##name
  GET	(n,			"R.n -> N")
  GET	(e,			"R.e -> E")
#undef GETSETNAME
  { 0 }
};

static PyMethodDef rsapub_pymethods[] = {
#define METHNAME(name) rsameth_##name
  METH	(pubop,			"R.pubop(X) -> X^E (mod N)")
#undef METHNAME
  { 0 }
};

static PyGetSetDef rsapriv_pygetset[] = {
#define GETSETNAME(op, name) rsa##op##_##name
  GET	(d,			"R.d -> D")
  GET	(p,			"R.p -> P")
  GET	(q,			"R.q -> Q")
  GET	(dp,			"R.dp -> D mod (P - 1)")
  GET	(dq,			"R.dq -> D mod (Q - 1)")
  GET	(q_inv,			"R.q_inv -> Q^{-1} mod P")
  GETSET(rng,			"R.rng -> random number source for blinding")
#undef GETSETNAME
  { 0 }
};

static PyMethodDef rsapriv_pymethods[] = {
#define METHNAME(name) rsameth_##name
  KWMETH(privop,		"R.privop(X, rng = None) -> X^D (mod N)")
#undef METHNAME
  { 0 }
};

static PyTypeObject rsapub_pytype_skel = {
  PyObject_HEAD_INIT(0) 0,		/* Header */
  "RSAPub",				/* @tp_name@ */
  sizeof(rsapub_pyobj),			/* @tp_basicsize@ */
  0,					/* @tp_itemsize@ */

  rsapub_pydealloc,			/* @tp_dealloc@ */
  0,					/* @tp_print@ */
  0,					/* @tp_getattr@ */
  0,					/* @tp_setattr@ */
  0,					/* @tp_compare@ */
  0,					/* @tp_repr@ */
  0,					/* @tp_as_number@ */
  0,					/* @tp_as_sequence@ */
  0,					/* @tp_as_mapping@ */
  0,					/* @tp_hash@ */
  0,					/* @tp_call@ */
  0,					/* @tp_str@ */
  0,					/* @tp_getattro@ */
  0,					/* @tp_setattro@ */
  0,					/* @tp_as_buffer@ */
  Py_TPFLAGS_DEFAULT |			/* @tp_flags@ */
    Py_TPFLAGS_BASETYPE,

  /* @tp_doc@ */
"RSA public key information.",

  0,					/* @tp_traverse@ */
  0,					/* @tp_clear@ */
  0,					/* @tp_richcompare@ */
  0,					/* @tp_weaklistoffset@ */
  0,					/* @tp_iter@ */
  0,					/* @tp_iternext@ */
  rsapub_pymethods,			/* @tp_methods@ */
  0,					/* @tp_members@ */
  rsapub_pygetset,			/* @tp_getset@ */
  0,					/* @tp_base@ */
  0,					/* @tp_dict@ */
  0,					/* @tp_descr_get@ */
  0,					/* @tp_descr_set@ */
  0,					/* @tp_dictoffset@ */
  0,					/* @tp_init@ */
  PyType_GenericAlloc,			/* @tp_alloc@ */
  rsapub_pynew,				/* @tp_new@ */
  0,					/* @tp_free@ */
  0					/* @tp_is_gc@ */
};

static PyTypeObject rsapriv_pytype_skel = {
  PyObject_HEAD_INIT(0) 0,		/* Header */
  "RSAPriv",				/* @tp_name@ */
  sizeof(rsapriv_pyobj),		/* @tp_basicsize@ */
  0,					/* @tp_itemsize@ */

  rsapriv_pydealloc,			/* @tp_dealloc@ */
  0,					/* @tp_print@ */
  0,					/* @tp_getattr@ */
  0,					/* @tp_setattr@ */
  0,					/* @tp_compare@ */
  0,					/* @tp_repr@ */
  0,					/* @tp_as_number@ */
  0,					/* @tp_as_sequence@ */
  0,					/* @tp_as_mapping@ */
  0,					/* @tp_hash@ */
  0,					/* @tp_call@ */
  0,					/* @tp_str@ */
  0,					/* @tp_getattro@ */
  0,					/* @tp_setattro@ */
  0,					/* @tp_as_buffer@ */
  Py_TPFLAGS_DEFAULT |			/* @tp_flags@ */
    Py_TPFLAGS_BASETYPE,

  /* @tp_doc@ */
"RSA private key information.",

  0,					/* @tp_traverse@ */
  0,					/* @tp_clear@ */
  0,					/* @tp_richcompare@ */
  0,					/* @tp_weaklistoffset@ */
  0,					/* @tp_iter@ */
  0,					/* @tp_iternext@ */
  rsapriv_pymethods,			/* @tp_methods@ */
  0,					/* @tp_members@ */
  rsapriv_pygetset,			/* @tp_getset@ */
  0,					/* @tp_base@ */
  0,					/* @tp_dict@ */
  0,					/* @tp_descr_get@ */
  0,					/* @tp_descr_set@ */
  0,					/* @tp_dictoffset@ */
  0,					/* @tp_init@ */
  PyType_GenericAlloc,			/* @tp_alloc@ */
  rsapriv_pynew,			/* @tp_new@ */
  0,					/* @tp_free@ */
  0					/* @tp_is_gc@ */
};

/*----- RSA padding schemes -----------------------------------------------*/

static PyObject *meth__p1crypt_encode(PyObject *me,
				      PyObject *arg, PyObject *kw)
{
  pkcs1 p1;
  char *m, *ep;
  int msz, epsz;
  unsigned long nbits;
  PyObject *rc = 0;
  octet *b = 0;
  size_t sz;
  mp *x;
  char *kwlist[] = { "msg", "nbits", "ep", "rng", 0 };

  p1.r = &rand_global; ep = 0; epsz = 0;
  if (!PyArg_ParseTupleAndKeywords(arg, kw, "s#O&|s#O&:encode", kwlist,
				   &m, &msz, convulong, &nbits,
				   &ep, &epsz, convgrand, &p1.r))
    goto end;
  sz = (nbits + 7)/8;
  p1.ep = ep; p1.epsz = epsz;
  if (epsz + msz + 11 > sz) VALERR("buffer underflow");
  b = xmalloc(sz);
  x = pkcs1_cryptencode(MP_NEW, m, msz, b, sz, nbits, &p1);
  rc = mp_pywrap(x);
end:
  xfree(b);
  return (rc);
}

static PyObject *meth__p1crypt_decode(PyObject *me,
				      PyObject *arg, PyObject *kw)
{
  pkcs1 p1;
  char *ep;
  int epsz;
  unsigned long nbits;
  int n;
  PyObject *rc = 0;
  octet *b = 0;
  size_t sz;
  mp *x = 0;
  char *kwlist[] = { "ct", "nbits", "ep", "rng", 0 };

  p1.r = &rand_global; ep = 0; epsz = 0;
  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O&O&|s#O&:decode", kwlist,
				   convmp, &x, convulong, &nbits,
				   &ep, &epsz, convgrand, &p1.r))
    goto end;
  sz = (nbits + 7)/8;
  p1.ep = ep; p1.epsz = epsz;
  if (epsz + 11 > sz) VALERR("buffer underflow");
  b = xmalloc(sz);
  if ((n = pkcs1_cryptdecode(x, b, sz, nbits, &p1)) < 0)
    VALERR("decryption failed");
  rc = bytestring_pywrap(b, n);
end:
  mp_drop(x);
  xfree(b);
  return (rc);
}

static PyObject *meth__p1sig_encode(PyObject *me,
				    PyObject *arg, PyObject *kw)
{
  pkcs1 p1;
  char *m, *ep;
  int msz, epsz;
  unsigned long nbits;
  PyObject *rc = 0;
  octet *b = 0;
  size_t sz;
  mp *x;
  char *kwlist[] = { "msg", "nbits", "ep", "rng", 0 };

  p1.r = &rand_global; ep = 0; epsz = 0;
  if (!PyArg_ParseTupleAndKeywords(arg, kw, "s#O&|s#O&:encode", kwlist,
				   &m, &msz, convulong, &nbits,
				   &ep, &epsz, convgrand, &p1.r))
    goto end;
  sz = (nbits + 7)/8;
  p1.ep = ep; p1.epsz = epsz;
  if (epsz + msz + 11 > sz) VALERR("buffer underflow");
  b = xmalloc(sz);
  x = pkcs1_sigencode(MP_NEW, m, msz, b, sz, nbits, &p1);
  rc = mp_pywrap(x);
end:
  xfree(b);
  return (rc);
}

static PyObject *meth__p1sig_decode(PyObject *me,
				    PyObject *arg, PyObject *kw)
{
  pkcs1 p1;
  char *ep;
  int epsz;
  unsigned long nbits;
  int n;
  PyObject *hukairz;
  PyObject *rc = 0;
  octet *b = 0;
  size_t sz;
  mp *x = 0;
  char *kwlist[] = { "msg", "sig", "nbits", "ep", "rng", 0 };

  p1.r = &rand_global; ep = 0; epsz = 0;
  if (!PyArg_ParseTupleAndKeywords(arg, kw, "OO&O&|s#O&:decode", kwlist,
				   &hukairz, convmp, &x, convulong, &nbits,
				   &ep, &epsz, convgrand, &p1.r))
    goto end;
  sz = (nbits + 7)/8;
  p1.ep = ep; p1.epsz = epsz;
  if (epsz + 10 > sz) VALERR("buffer underflow");
  b = xmalloc(sz);
  if ((n = pkcs1_sigdecode(x, 0, 0, b, sz, nbits, &p1)) < 0)
    VALERR("verification failed");
  rc = bytestring_pywrap(b, n);
end:
  mp_drop(x);
  xfree(b);
  return (rc);
}

static PyObject *meth__oaep_encode(PyObject *me,
				   PyObject *arg, PyObject *kw)
{
  oaep o;
  char *m, *ep;
  int msz, epsz;
  unsigned long nbits;
  PyObject *rc = 0;
  octet *b = 0;
  size_t sz;
  mp *x;
  char *kwlist[] = { "msg", "nbits", "mgf", "hash", "ep", "rng", 0 };

  o.r = &rand_global; o.cc = &sha_mgf; o.ch = &sha; ep = 0; epsz = 0;
  if (!PyArg_ParseTupleAndKeywords(arg, kw, "s#O&|O&O&s#O&:encode", kwlist,
				   &m, &msz, convulong, &nbits,
				   convgccipher, &o.cc,
				   convgchash, &o.ch,
				   &ep, &epsz,
				   convgrand, &o.r))
    goto end;
  sz = (nbits + 7)/8;
  o.ep = ep; o.epsz = epsz;
  if (2 * o.ch->hashsz + 2 + msz > sz) VALERR("buffer underflow");
  b = xmalloc(sz);
  x = oaep_encode(MP_NEW, m, msz, b, sz, nbits, &o);
  rc = mp_pywrap(x);
end:
  xfree(b);
  return (rc);
}

static PyObject *meth__oaep_decode(PyObject *me,
				   PyObject *arg, PyObject *kw)
{
  oaep o;
  char *ep;
  int epsz;
  unsigned long nbits;
  int n;
  PyObject *rc = 0;
  octet *b = 0;
  size_t sz;
  mp *x = 0;
  char *kwlist[] = { "ct", "nbits", "mgf", "hash", "ep", "rng", 0 };

  o.r = &rand_global; o.cc = &sha_mgf; o.ch = &sha; ep = 0; epsz = 0;
  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O&O&|O&O&s#O&:decode", kwlist,
				   convmp, &x, convulong, &nbits,
				   convgccipher, &o.cc,
				   convgchash, &o.ch,
				   &ep, &epsz,
				   convgrand, &o.r))
    goto end;
  sz = (nbits + 7)/8;
  o.ep = ep; o.epsz = epsz;
  if (2 * o.ch->hashsz > sz) VALERR("buffer underflow");
  b = xmalloc(sz);
  if ((n = oaep_decode(x, b, sz, nbits, &o)) < 0)
    VALERR("decryption failed");
  rc = bytestring_pywrap(b, n);
end:
  mp_drop(x);
  xfree(b);
  return (rc);
}

static PyObject *meth__pss_encode(PyObject *me,
				  PyObject *arg, PyObject *kw)
{
  pss p;
  char *m;
  int msz;
  unsigned long nbits;
  PyObject *rc = 0;
  octet *b = 0;
  size_t sz;
  mp *x = 0;
  char *kwlist[] = { "msg", "nbits", "mgf", "hash", "saltsz", "rng", 0 };

  p.cc = &sha_mgf; p.ch = &sha; p.r = &rand_global; p.ssz = (size_t)-1;
  if (!PyArg_ParseTupleAndKeywords(arg, kw, "s#O&|O&O&O&O&:encode", kwlist,
				   &m, &msz, convulong, &nbits,
				   convgccipher, &p.cc,
				   convgchash, &p.ch,
				   convszt, &p.ssz,
				   convgrand, &p.r))
    goto end;
  sz = (nbits + 7)/8;
  if (p.ssz == (size_t)-1) p.ssz = p.ch->hashsz;
  if (p.ch->hashsz + p.ssz + 2 > sz) VALERR("buffer underflow");
  b = xmalloc(sz);
  x = pss_encode(MP_NEW, m, msz, b, sz, nbits, &p);
  rc = mp_pywrap(x);
end:
  xfree(b);
  return (rc);
}

static PyObject *meth__pss_decode(PyObject *me,
				  PyObject *arg, PyObject *kw)
{
  pss p;
  char *m;
  int msz;
  unsigned long nbits;
  PyObject *rc = 0;
  octet *b = 0;
  size_t sz;
  int n;
  mp *x = 0;
  char *kwlist[] =
    { "msg", "sig", "nbits", "mgf", "hash", "saltsz", "rng", 0 };

  p.cc = &sha_mgf; p.ch = &sha; p.r = &rand_global; p.ssz = (size_t)-1;
  if (!PyArg_ParseTupleAndKeywords(arg, kw, "s#O&O&|O&O&O&O&:decode", kwlist,
				   &m, &msz, convmp, &x, convulong, &nbits,
				   convgccipher, &p.cc,
				   convgchash, &p.ch,
				   convszt, &p.ssz,
				   convgrand, &p.r))
    goto end;
  sz = (nbits + 7)/8;
  if (p.ssz == (size_t)-1) p.ssz = p.ch->hashsz;
  if (p.ch->hashsz + p.ssz + 2 > sz) VALERR("buffer underflow");
  b = xmalloc(sz);
  if ((n = pss_decode(x, m, msz, b, sz, nbits, &p)) < 0)
    VALERR("verification failed");
  rc = Py_None; Py_INCREF(rc);
end:
  mp_drop(x);
  xfree(b);
  return (rc);
}

/*----- Global stuff ------------------------------------------------------*/

static PyMethodDef methods[] = {
#define METHNAME(name) meth_##name
  KWMETH(_p1crypt_encode,		0)
  KWMETH(_p1crypt_decode,		0)
  KWMETH(_p1sig_encode,			0)
  KWMETH(_p1sig_decode,			0)
  KWMETH(_oaep_encode,			0)
  KWMETH(_oaep_decode,			0)
  KWMETH(_pss_encode,			0)
  KWMETH(_pss_decode,			0)
  KWMETH(_RSAPriv_generate,		"\
generate(NBITS, [event = pgen_nullev, rng = rand, nsteps = 0]) -> R")
#undef METHNAME
  { 0 }
};

void pubkey_pyinit(void)
{
  INITTYPE(dsapub, root);
  INITTYPE(dsapriv, dsapub);
  INITTYPE(kcdsapub, root);
  INITTYPE(kcdsapriv, kcdsapub);
  INITTYPE(rsapub, root);
  INITTYPE(rsapriv, rsapub);
  addmethods(methods);
}

void pubkey_pyinsert(PyObject *mod)
{
  INSERT("DSAPub", dsapub_pytype);
  INSERT("DSAPriv", dsapriv_pytype);
  INSERT("KCDSAPub", kcdsapub_pytype);
  INSERT("KCDSAPriv", kcdsapriv_pytype);
  INSERT("RSAPub", rsapub_pytype);
  INSERT("RSAPriv", rsapriv_pytype);
}

/*----- That's all, folks -------------------------------------------------*/