From 16178155513725d7fee6e61316c200aaed7eff17 Mon Sep 17 00:00:00 2001 Message-Id: <16178155513725d7fee6e61316c200aaed7eff17.1716318565.git.mdw@distorted.org.uk> From: Mark Wooding Date: Mon, 1 May 2017 01:38:30 +0100 Subject: [PATCH] pubkey.c: Change the arguments to {DSA,KCDSA}{Pub,Priv}. Organization: Straylight/Edgeware From: Mark Wooding * Don't allow a private-key `u' argument to `*Pub'. * Have the private key argument `u' precede the public key `p' to `*Priv'. * Make the public key optional to `*Priv', and compute it correctly if not provided. This is an incompatible change, but I've resolved not to care. The old interface was obviously crazy. --- pubkey.c | 63 +++++++++++++++++++++++++++++++++++--------------------- 1 file changed, 40 insertions(+), 23 deletions(-) diff --git a/pubkey.c b/pubkey.c index 5292717..4067ae0 100644 --- 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); -- [mdw]