X-Git-Url: https://git.distorted.org.uk/~mdw/catacomb-python/blobdiff_plain/620169aef06f74c9a8574e28b5482061e81a7389..be17c8c27ee7ae2e14fe34bb517484a11b1cf300:/algorithms.c

diff --git a/algorithms.c b/algorithms.c
index 9dbebe6..babee57 100644
--- a/algorithms.c
+++ b/algorithms.c
@@ -526,14 +526,13 @@ static PyObject *gcipher_pywrap(PyObject *cobj, gcipher *c)
 static PyObject *gcipher_pynew(PyTypeObject *ty, PyObject *arg, PyObject *kw)
 {
   static const char *const kwlist[] = { "k", 0 };
-  char *k;
-  Py_ssize_t sz;
+  struct bin k;
 
-  if (!PyArg_ParseTupleAndKeywords(arg, kw, "s#:new", KWLIST, &k, &sz))
+  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O&:new", KWLIST, convbin, &k))
     goto end;
-  if (keysz(sz, GCCIPHER_CC(ty)->keysz) != sz) VALERR("bad key length");
+  if (keysz(k.sz, GCCIPHER_CC(ty)->keysz) != k.sz) VALERR("bad key length");
   return (gcipher_pywrap((PyObject *)ty,
-			 GC_INIT(GCCIPHER_CC(ty), k, sz)));
+			 GC_INIT(GCCIPHER_CC(ty), k.p, k.sz)));
 end:
   return (0);
 }
@@ -573,13 +572,12 @@ static PyObject *gccget_blksz(PyObject *me, void *hunoz)
 
 static PyObject *gcmeth_encrypt(PyObject *me, PyObject *arg)
 {
-  char *p;
-  Py_ssize_t sz;
+  struct bin m;
   PyObject *rc = 0;
 
-  if (!PyArg_ParseTuple(arg, "s#:encrypt", &p, &sz)) return (0);
-  rc = bytestring_pywrap(0, sz);
-  GC_ENCRYPT(GCIPHER_C(me), p, PyString_AS_STRING(rc), sz);
+  if (!PyArg_ParseTuple(arg, "O&:encrypt", convbin, &m)) return (0);
+  rc = bytestring_pywrap(0, m.sz);
+  GC_ENCRYPT(GCIPHER_C(me), m.p, PyString_AS_STRING(rc), m.sz);
   return (rc);
 }
 
@@ -599,13 +597,12 @@ static PyObject *gcmeth_enczero(PyObject *me, PyObject *arg)
 
 static PyObject *gcmeth_decrypt(PyObject *me, PyObject *arg)
 {
-  char *p;
-  Py_ssize_t sz;
+  struct bin c;
   PyObject *rc = 0;
 
-  if (!PyArg_ParseTuple(arg, "s#:decrypt", &p, &sz)) return (0);
-  rc = bytestring_pywrap(0, sz);
-  GC_DECRYPT(GCIPHER_C(me), p, PyString_AS_STRING(rc), sz);
+  if (!PyArg_ParseTuple(arg, "O&:decrypt", convbin, &c)) return (0);
+  rc = bytestring_pywrap(0, c.sz);
+  GC_DECRYPT(GCIPHER_C(me), c.p, PyString_AS_STRING(rc), c.sz);
   return (rc);
 }
 
@@ -625,14 +622,13 @@ static PyObject *gcmeth_deczero(PyObject *me, PyObject *arg)
 
 static PyObject *gcmeth_setiv(PyObject *me, PyObject *arg)
 {
-  char *p;
-  Py_ssize_t sz;
+  struct bin iv;
 
-  if (!PyArg_ParseTuple(arg, "s#:setiv", &p, &sz)) goto end;
+  if (!PyArg_ParseTuple(arg, "O&:setiv", convbin, &iv)) goto end;
   if (!GCIPHER_C(me)->ops->setiv) VALERR("`setiv' not supported");
   if (!GC_CLASS(GCIPHER_C(me))->blksz) VALERR("not a block cipher mode");
-  if (sz != GC_CLASS(GCIPHER_C(me))->blksz) VALERR("bad IV length");
-  GC_SETIV(GCIPHER_C(me), p);
+  if (iv.sz != GC_CLASS(GCIPHER_C(me))->blksz) VALERR("bad IV length");
+  GC_SETIV(GCIPHER_C(me), iv.p);
   RETURN_ME;
 end:
   return (0);
@@ -886,14 +882,13 @@ static PyObject *gaeadkey_pynew(PyTypeObject *ty,
 				PyObject *arg, PyObject *kw)
 {
   static const char *const kwlist[] = { "k", 0 };
-  char *k;
-  Py_ssize_t sz;
+  struct bin k;
 
-  if (!PyArg_ParseTupleAndKeywords(arg, kw, "s#:new", KWLIST, &k, &sz))
+  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O&:new", KWLIST, convbin, &k))
     goto end;
-  if (keysz(sz, GCAEAD_AEC(ty)->keysz) != sz) VALERR("bad key length");
+  if (keysz(k.sz, GCAEAD_AEC(ty)->keysz) != k.sz) VALERR("bad key length");
   return (gaeadkey_pywrap((PyObject *)ty,
-			  GAEAD_KEY(GCAEAD_AEC(ty), k, sz)));
+			  GAEAD_KEY(GCAEAD_AEC(ty), k.p, k.sz)));
 end:
   return (0);
 }
@@ -1018,18 +1013,18 @@ static PyObject *gaekmeth_enc(PyObject *me, PyObject *arg, PyObject *kw)
   const gaead_key *k = GAEADKEY_K(me);
   gaead_enc *e;
   PyObject *rc = 0;
-  char *n; Py_ssize_t nsz;
+  struct bin n;
   PyObject *hszobj = Py_None, *mszobj = Py_None, *tszobj = Py_None;
   size_t hsz = 0, msz = 0, tsz = 0;
   unsigned f;
 
-  if (!PyArg_ParseTupleAndKeywords(arg, kw, "s#|OOO:enc", KWLIST,
-				   &n, &nsz, &hszobj, &mszobj, &tszobj))
+  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O&|OOO:enc", KWLIST,
+				   convbin, &n, &hszobj, &mszobj, &tszobj))
     goto end;
-  if (check_aead_encdec(k->ops->c, &f, nsz,
+  if (check_aead_encdec(k->ops->c, &f, n.sz,
 			hszobj, &hsz, mszobj, &msz, tszobj, &tsz))
     goto end;
-  e = GAEAD_ENC(GAEADKEY_K(me), n, nsz, hsz, msz, tsz);
+  e = GAEAD_ENC(GAEADKEY_K(me), n.p, n.sz, hsz, msz, tsz);
   if (!e) VALERR("bad aead parameter combination");
   rc = gaeadenc_pywrap((PyObject *)GCAEAD_ENC(Py_TYPE(me)),
 		       e, f, hsz, msz, tsz);
@@ -1043,18 +1038,18 @@ static PyObject *gaekmeth_dec(PyObject *me, PyObject *arg, PyObject *kw)
   const gaead_key *k = GAEADKEY_K(me);
   gaead_dec *d;
   PyObject *rc = 0;
-  char *n; Py_ssize_t nsz;
+  struct bin n;
   PyObject *hszobj = Py_None, *cszobj = Py_None, *tszobj = Py_None;
   size_t hsz = 0, csz = 0, tsz = 0;
   unsigned f;
 
-  if (!PyArg_ParseTupleAndKeywords(arg, kw, "s#|OOO:dec", KWLIST,
-				   &n, &nsz, &hszobj, &cszobj, &tszobj))
+  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O&|OOO:dec", KWLIST,
+				   convbin, &n, &hszobj, &cszobj, &tszobj))
     goto end;
-  if (check_aead_encdec(k->ops->c, &f, nsz,
+  if (check_aead_encdec(k->ops->c, &f, n.sz,
 			hszobj, &hsz, cszobj, &csz, tszobj, &tsz))
     goto end;
-  d = GAEAD_DEC(GAEADKEY_K(me), n, nsz, hsz, csz, tsz);
+  d = GAEAD_DEC(GAEADKEY_K(me), n.p, n.sz, hsz, csz, tsz);
   if (!d) VALERR("bad aead parameter combination");
   rc = gaeaddec_pywrap((PyObject *)GCAEAD_DEC(Py_TYPE(me)),
 		       d, f, hsz, csz, tsz);
@@ -1161,10 +1156,10 @@ end:
 
 static PyObject *gaeameth_hash(PyObject *me, PyObject *arg)
 {
-  char *h; Py_ssize_t hsz;
+  struct bin h;
 
-  if (!PyArg_ParseTuple(arg, "s#:hash", &h, &hsz)) return (0);
-  if (gaeadaad_hash(me, h, hsz)) return (0);
+  if (!PyArg_ParseTuple(arg, "O&:hash", convbin, &h)) return (0);
+  if (gaeadaad_hash(me, h.p, h.sz)) return (0);
   RETURN_ME;
 }
 
@@ -1181,11 +1176,11 @@ DOUINTCONV(GAEAMETH_HASHU_)
 #define GAEAMETH_HASHBUF_(n, W, w)					\
   static PyObject *gaeameth_hashbuf##w(PyObject *me, PyObject *arg)	\
   {									\
-    char *p; Py_ssize_t sz; octet b[SZ_##W];				\
-    if (!PyArg_ParseTuple(arg, "s#:hashbuf" #w, &p, &sz)) goto end;	\
-    if (sz > MASK##n) TYERR("string too long");				\
-    STORE##W(b, sz); if (gaeadaad_hash(me, b, sizeof(b))) goto end;	\
-    if (gaeadaad_hash(me, p, sz)) goto end;				\
+    struct bin in; octet b[SZ_##W];					\
+    if (!PyArg_ParseTuple(arg, "O&:hashbuf" #w, convbin, &in)) goto end; \
+    if (in.sz > MASK##n) TYERR("string too long");			\
+    STORE##W(b, in.sz); if (gaeadaad_hash(me, b, sizeof(b))) goto end;	\
+    if (gaeadaad_hash(me, in.p, in.sz)) goto end;			\
     RETURN_ME;								\
   end:									\
     return (0);								\
@@ -1293,18 +1288,18 @@ static PyObject *gaeemeth_reinit(PyObject *me, PyObject *arg, PyObject *kw)
 {
   static const char *const kwlist[] = { "nonce", "hsz", "msz", "tsz", 0 };
   gaeadenc_pyobj *ge = (gaeadenc_pyobj *)me;
-  char *n; Py_ssize_t nsz;
+  struct bin n;
   PyObject *hszobj = Py_None, *mszobj = Py_None, *tszobj = Py_None;
   size_t hsz = 0, msz = 0, tsz = 0;
   unsigned f;
 
-  if (!PyArg_ParseTupleAndKeywords(arg, kw, "s#|OOO:enc", KWLIST,
-				   &n, &nsz, &hszobj, &mszobj, &tszobj))
+  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O&|OOO:enc", KWLIST,
+				   convbin, &n, &hszobj, &mszobj, &tszobj))
     goto end;
-  if (check_aead_encdec(ge->e->ops->c, &f, nsz,
+  if (check_aead_encdec(ge->e->ops->c, &f, n.sz,
 			hszobj, &hsz, mszobj, &msz, tszobj, &tsz))
     goto end;
-  if (GAEAD_REINIT(ge->e, n, nsz, hsz, msz, tsz))
+  if (GAEAD_REINIT(ge->e, n.p, n.sz, hsz, msz, tsz))
     VALERR("bad aead parameter combination");
   gaea_sever(&ge->aad);
   ge->f = f; ge->hsz = hsz; ge->msz = msz; ge->tsz = tsz;
@@ -1315,22 +1310,22 @@ end:
 static PyObject *gaeemeth_encrypt(PyObject *me, PyObject *arg)
 {
   gaeadenc_pyobj *ge = (gaeadenc_pyobj *)me;
-  char *m; Py_ssize_t msz;
+  struct bin m;
   char *c = 0; size_t csz; buf b;
   int err;
   PyObject *rc = 0;
 
-  if (!PyArg_ParseTuple(arg, "s#:encrypt", &m, &msz)) goto end;
+  if (!PyArg_ParseTuple(arg, "O&:encrypt", convbin, &m)) goto end;
   if (ge->f&AEADF_AADFIRST) {
     if ((ge->f&AEADF_PCHSZ) && (ge->aad ? ge->aad->hlen : 0) != ge->hsz)
       VALERR("header doesn't match precommitted length");
     gaea_invalidate(ge->aad);
   }
-  if ((ge->f&AEADF_PCMSZ) && msz > ge->msz - ge->mlen)
+  if ((ge->f&AEADF_PCMSZ) && m.sz > ge->msz - ge->mlen)
     VALERR("too large for precommitted message length");
-  csz = msz + ge->e->ops->c->bufsz; c = xmalloc(csz); buf_init(&b, c, csz);
-  err = GAEAD_ENCRYPT(ge->e, m, msz, &b); assert(!err); (void)err;
-  buf_flip(&b); rc = bytestring_pywrapbuf(&b); ge->mlen += msz;
+  csz = m.sz + ge->e->ops->c->bufsz; c = xmalloc(csz); buf_init(&b, c, csz);
+  err = GAEAD_ENCRYPT(ge->e, m.p, m.sz, &b); assert(!err); (void)err;
+  buf_flip(&b); rc = bytestring_pywrapbuf(&b); ge->mlen += m.sz;
 end:
   xfree(c);
   return (rc);
@@ -1462,18 +1457,18 @@ static PyObject *gaedmeth_reinit(PyObject *me, PyObject *arg, PyObject *kw)
 {
   static const char *const kwlist[] = { "nonce", "hsz", "csz", "tsz", 0 };
   gaeaddec_pyobj *gd = (gaeaddec_pyobj *)me;
-  char *n; Py_ssize_t nsz;
+  struct bin n;
   PyObject *hszobj = Py_None, *cszobj = Py_None, *tszobj = Py_None;
   size_t hsz = 0, csz = 0, tsz = 0;
   unsigned f;
 
-  if (!PyArg_ParseTupleAndKeywords(arg, kw, "s#|OOO:enc", KWLIST,
-				   &n, &nsz, &hszobj, &cszobj, &tszobj))
+  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O&|OOO:enc", KWLIST,
+				   convbin, &n, &hszobj, &cszobj, &tszobj))
     goto end;
-  if (check_aead_encdec(gd->d->ops->c, &f, nsz,
+  if (check_aead_encdec(gd->d->ops->c, &f, n.sz,
 			hszobj, &hsz, cszobj, &csz, tszobj, &tsz))
     goto end;
-  if (GAEAD_REINIT(gd->d, n, nsz, hsz, csz, tsz))
+  if (GAEAD_REINIT(gd->d, n.p, n.sz, hsz, csz, tsz))
     VALERR("bad aead parameter combination");
   gaea_sever(&gd->aad);
   gd->f = f; gd->hsz = hsz; gd->csz = csz; gd->tsz = tsz;
@@ -1484,22 +1479,22 @@ end:
 static PyObject *gaedmeth_decrypt(PyObject *me, PyObject *arg)
 {
   gaeaddec_pyobj *gd = (gaeaddec_pyobj *)me;
-  char *c; Py_ssize_t csz;
+  struct bin c;
   char *m = 0; size_t msz; buf b;
   int err;
   PyObject *rc = 0;
 
-  if (!PyArg_ParseTuple(arg, "s#:decrypt", &c, &csz)) goto end;
+  if (!PyArg_ParseTuple(arg, "O&:decrypt", convbin, &c)) goto end;
   if (gd->f&AEADF_AADFIRST) {
     if ((gd->f&AEADF_PCHSZ) && (gd->aad ? gd->aad->hlen : 0) != gd->hsz)
       VALERR("header doesn't match precommitted length");
     gaea_invalidate(gd->aad);
   }
-  if ((gd->f&AEADF_PCMSZ) && csz > gd->csz - gd->clen)
+  if ((gd->f&AEADF_PCMSZ) && c.sz > gd->csz - gd->clen)
     VALERR("too large for precommitted message length");
-  msz = csz + gd->d->ops->c->bufsz; m = xmalloc(msz); buf_init(&b, m, msz);
-  err = GAEAD_DECRYPT(gd->d, c, csz, &b); assert(!err); (void)err;
-  buf_flip(&b); rc = bytestring_pywrapbuf(&b); gd->clen += csz;
+  msz = c.sz + gd->d->ops->c->bufsz; m = xmalloc(msz); buf_init(&b, m, msz);
+  err = GAEAD_DECRYPT(gd->d, c.p, c.sz, &b); assert(!err); (void)err;
+  buf_flip(&b); rc = bytestring_pywrapbuf(&b); gd->clen += c.sz;
 end:
   xfree(m);
   return (rc);
@@ -1510,13 +1505,13 @@ static PyObject *gaedmeth_done(PyObject *me, PyObject *arg, PyObject *kw)
   static const char *const kwlist[] = { "tag", "aad", 0 };
   gaeaddec_pyobj *gd = (gaeaddec_pyobj *)me;
   PyObject *aad = Py_None;
-  char *t; Py_ssize_t tsz;
+  struct bin t;
   char *m = 0; size_t msz; buf b;
   int err;
   PyObject *rc = 0;
 
-  if (!PyArg_ParseTupleAndKeywords(arg, kw, "s#|O:done", KWLIST,
-				   &t, &tsz, &aad))
+  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O&|O:done", KWLIST,
+				   convbin, &t, &aad))
     goto end;
   if (aad != Py_None &&
       !PyObject_TypeCheck(aad,
@@ -1529,11 +1524,12 @@ static PyObject *gaedmeth_done(PyObject *me, PyObject *arg, PyObject *kw)
     VALERR("header doesn't match precommitted length");
   if ((gd->f&AEADF_PCMSZ) && gd->clen != gd->csz)
     VALERR("message doesn't match precommitted length");
-  if ((gd->f&AEADF_PCTSZ) && tsz != gd->tsz)
+  if ((gd->f&AEADF_PCTSZ) && t.sz != gd->tsz)
     VALERR("tag length doesn't match precommitted value");
-  if (keysz(tsz, gd->d->ops->c->tagsz) != tsz) VALERR("bad tag length");
+  if (keysz(t.sz, gd->d->ops->c->tagsz) != t.sz) VALERR("bad tag length");
   msz = gd->d->ops->c->bufsz; m = xmalloc(msz); buf_init(&b, m, msz);
-  err = GAEAD_DONE(gd->d, aad == Py_None ? 0 : GAEADAAD_A(aad), &b, t, tsz);
+  err = GAEAD_DONE(gd->d, aad == Py_None ? 0 : GAEADAAD_A(aad),
+		   &b, t.p, t.sz);
   assert(err >= 0);
   if (!err) VALERR("decryption failed");
   buf_flip(&b); rc = bytestring_pywrapbuf(&b);
@@ -2011,10 +2007,9 @@ static PyObject *ghmeth_copy(PyObject *me)
 
 static PyObject *ghmeth_hash(PyObject *me, PyObject *arg)
 {
-  char *p;
-  Py_ssize_t sz;
-  if (!PyArg_ParseTuple(arg, "s#:hash", &p, &sz)) return (0);
-  GH_HASH(GHASH_H(me), p, sz);
+  struct bin m;
+  if (!PyArg_ParseTuple(arg, "O&:hash", convbin, &m)) return (0);
+  GH_HASH(GHASH_H(me), m.p, m.sz);
   RETURN_ME;
 }
 
@@ -2031,11 +2026,10 @@ DOUINTCONV(GHMETH_HASHU_)
 #define GHMETH_HASHBUF_(n, W, w)					\
   static PyObject *ghmeth_hashbuf##w(PyObject *me, PyObject *arg)	\
   {									\
-    char *p;								\
-    Py_ssize_t sz;							\
-    if (!PyArg_ParseTuple(arg, "s#:hashbuf" #w, &p, &sz)) goto end;	\
-    if (sz > MASK##n) TYERR("string too long");				\
-    GH_HASHBUF##W(GHASH_H(me), p, sz);					\
+    struct bin in;							\
+    if (!PyArg_ParseTuple(arg, "O&:hashbuf" #w, convbin, &in)) goto end; \
+    if (in.sz > MASK##n) TYERR("string too long");			\
+    GH_HASHBUF##W(GHASH_H(me), in.p, in.sz);				\
     RETURN_ME;								\
   end:									\
     return (0);								\
@@ -2212,14 +2206,13 @@ extern int convgmac(PyObject *, void *);
 static PyObject *gmac_pynew(PyTypeObject *ty, PyObject *arg, PyObject *kw)
 {
   static const char *const kwlist[] = { "k", 0 };
-  char *k;
-  Py_ssize_t sz;
+  struct bin k;
 
-  if (!PyArg_ParseTupleAndKeywords(arg, kw, "s#:new", KWLIST, &k, &sz))
+  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O&:new", KWLIST, convbin, &k))
     goto end;
-  if (keysz(sz, GCMAC_CM(ty)->keysz) != sz) VALERR("bad key length");
+  if (keysz(k.sz, GCMAC_CM(ty)->keysz) != k.sz) VALERR("bad key length");
   return (gmac_pywrap((PyObject *)ty,
-		      GM_KEY(GCMAC_CM(ty), k, sz)));
+		      GM_KEY(GCMAC_CM(ty), k.p, k.sz)));
 end:
   return (0);
 }
@@ -2470,16 +2463,15 @@ static PyObject *poly1305hash_pynew(PyTypeObject *ty,
   static const char *const kwlist[] = { "mask", 0 };
   poly1305key_pyobj *pk = (poly1305key_pyobj *)ty;
   poly1305hash_pyobj *ph;
-  char *m = 0;
-  Py_ssize_t sz;
+  struct bin m = { 0, 0 };
 
-  if (!PyArg_ParseTupleAndKeywords(arg, kw, "|s#:new", KWLIST, &m, &sz))
+  if (!PyArg_ParseTupleAndKeywords(arg, kw, "|O&:new", KWLIST, convbin, &m))
     return (0);
-  if (m && sz != POLY1305_MASKSZ) VALERR("bad mask length");
+  if (m.p && m.sz != POLY1305_MASKSZ) VALERR("bad mask length");
   ph = PyObject_NEW(poly1305hash_pyobj, ty);
   ph->f = 0;
-  if (m) ph->f |= f_mask;
-  poly1305_macinit(&ph->ctx, &pk->k, m);
+  if (m.p) ph->f |= f_mask;
+  poly1305_macinit(&ph->ctx, &pk->k, m.p);
   Py_INCREF(ty);
   return ((PyObject *)ph);
 end:
@@ -2491,12 +2483,11 @@ static PyObject *poly1305key_pynew(PyTypeObject *ty,
 {
   static const char *const kwlist[] = { "k", 0 };
   poly1305key_pyobj *pk;
-  char *k;
-  Py_ssize_t sz;
+  struct bin k;
 
-  if (!PyArg_ParseTupleAndKeywords(arg, kw, "s#:new", KWLIST, &k, &sz))
+  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O&:new", KWLIST, convbin, &k))
     goto end;
-  if (keysz(sz, poly1305_keysz) != sz) VALERR("bad key length");
+  if (keysz(k.sz, poly1305_keysz) != k.sz) VALERR("bad key length");
 
   pk = newtype(ty, 0, 0);
   pk->ty.ht_name = PyString_FromString("poly1305(keyed)");
@@ -2512,7 +2503,7 @@ static PyObject *poly1305key_pynew(PyTypeObject *ty,
   pk->ty.ht_type.tp_new = poly1305hash_pynew;
   typeready(&pk->ty.ht_type);
 
-  poly1305_keyinit(&pk->k, k, sz);
+  poly1305_keyinit(&pk->k, k.p, k.sz);
   return ((PyObject *)pk);
 
 end:
@@ -2542,10 +2533,9 @@ static PyObject *polymeth_copy(PyObject *me)
 
 static PyObject *polymeth_hash(PyObject *me, PyObject *arg)
 {
-  char *p;
-  Py_ssize_t sz;
-  if (!PyArg_ParseTuple(arg, "s#:hash", &p, &sz)) return (0);
-  poly1305_hash(P1305_CTX(me), p, sz);
+  struct bin m;
+  if (!PyArg_ParseTuple(arg, "O&:hash", convbin, &m)) return (0);
+  poly1305_hash(P1305_CTX(me), m.p, m.sz);
   RETURN_ME;
 }
 
@@ -2563,13 +2553,12 @@ DOUINTCONV(POLYMETH_HASHU_)
 #define POLYMETH_HASHBUF_(n, W, w)					\
   static PyObject *polymeth_hashbuf##w(PyObject *me, PyObject *arg)	\
   {									\
-    char *p;								\
-    Py_ssize_t sz;							\
+    struct bin in;							\
     octet b[SZ_##W];							\
-    if (!PyArg_ParseTuple(arg, "s#:hashbuf" #w, &p, &sz)) goto end;	\
-    if (sz > MASK##n) TYERR("string too long");				\
-    STORE##W(b, sz); poly1305_hash(P1305_CTX(me), b, sizeof(b));	\
-    poly1305_hash(P1305_CTX(me), p, sz);				\
+    if (!PyArg_ParseTuple(arg, "O&:hashbuf" #w, convbin, &in)) goto end; \
+    if (in.sz > MASK##n) TYERR("string too long");			\
+    STORE##W(b, in.sz); poly1305_hash(P1305_CTX(me), b, sizeof(b));	\
+    poly1305_hash(P1305_CTX(me), in.p, in.sz);				\
     RETURN_ME;								\
   end:									\
     return (0);								\
@@ -2796,17 +2785,16 @@ static const PyTypeObject poly1305hash_pytype_skel = {
   static PyObject *meth_##hdance##_prf(PyObject *me, PyObject *arg)	\
   {									\
     dance##_ctx dance;							\
-    char *k, *n;							\
-    Py_ssize_t ksz, nsz;						\
+    struct bin k, n;							\
     PyObject *rc;							\
-    if (!PyArg_ParseTuple(arg, "s#s#:" #hdance "_prf",			\
-			  &k, &ksz, &n, &nsz))				\
+    if (!PyArg_ParseTuple(arg, "O&O&:" #hdance "_prf",			\
+			  convbin, &k, convbin, &n))			\
       goto end;								\
-    if (ksz != keysz(ksz, dance##_keysz)) VALERR("bad key length");	\
-    if (nsz != HDANCE##_INSZ) VALERR("bad input length");		\
+    if (k.sz != keysz(k.sz, dance##_keysz)) VALERR("bad key length");	\
+    if (n.sz != HDANCE##_INSZ) VALERR("bad input length");		\
     rc = bytestring_pywrap(0, HSALSA20_OUTSZ);				\
-    dance##_init(&dance, k, ksz, 0);					\
-    hdance##_prf(&dance, n, PyString_AS_STRING(rc));			\
+    dance##_init(&dance, k.p, k.sz, 0);					\
+    hdance##_prf(&dance, n.p, PyString_AS_STRING(rc));				\
     return (rc);							\
   end:									\
     return (0);								\
@@ -2860,11 +2848,12 @@ static PyObject *kxvikmeth_mix(PyObject *me, PyObject *arg)
   const octet *q;
   octet buf[8];
   unsigned i;
-  char *p; Py_ssize_t n;
+  struct bin in;
+  size_t n;
 
-  if (!PyArg_ParseTuple(arg, "s#:mix", &p, &n)) goto end;
-  if (n > 200) VALERR("out of range");
-  q = (const octet *)p;
+  if (!PyArg_ParseTuple(arg, "O&:mix", convbin, &in)) goto end;
+  if (in.sz > 200) VALERR("out of range");
+  q = in.p; n = in.sz;
   i = 0;
   while (n > 8) { LOAD64_L_(t[i], q); i++; q += 8; n -= 8; }
   if (n) {
@@ -2988,15 +2977,14 @@ static PyObject *shake_dopynew(void (*initfn)(shake_ctx *,
 			       PyObject *arg, PyObject *kw)
 {
   shake_pyobj *rc = 0;
-  char *p = 0, *f = 0;
-  Py_ssize_t psz = 0, fsz = 0;
+  struct bin p = { 0, 0 }, f = { 0, 0 };
   static const char *const kwlist[] = { "perso", "func", 0 };
 
-  if (!PyArg_ParseTupleAndKeywords(arg, kw, "|s#s#:new", KWLIST,
-				   &p, &psz, &f, &fsz))
+  if (!PyArg_ParseTupleAndKeywords(arg, kw, "|O&O&:new", KWLIST,
+				   convbin, &p, convbin, &f))
     goto end;
   rc = (shake_pyobj *)ty->tp_alloc(ty, 0);
-  initfn(&rc->h, f, fsz, p, psz);
+  initfn(&rc->h, f.p, f.sz, p.p, p.sz);
   rc->st = 0;
 end:
   return ((PyObject *)rc);
@@ -3020,11 +3008,10 @@ end:
 
 static PyObject *shakemeth_hash(PyObject *me, PyObject *arg)
 {
-  char *p;
-  Py_ssize_t sz;
-  if (!PyArg_ParseTuple(arg, "s#:hash", &p, &sz)) return (0);
+  struct bin m;
+  if (!PyArg_ParseTuple(arg, "O&:hash", convbin, &m)) return (0);
   if (shake_check(me, 0)) return (0);
-  shake_hash(SHAKE_H(me), p, sz);
+  shake_hash(SHAKE_H(me), m.p, m.sz);
   RETURN_ME;
 }
 
@@ -3043,14 +3030,13 @@ DOUINTCONV(SHAKEMETH_HASHU_)
 #define SHAKEMETH_HASHBUF_(n, W, w)					\
   static PyObject *shakemeth_hashbuf##w(PyObject *me, PyObject *arg)	\
   {									\
-    char *p;								\
-    Py_ssize_t sz;							\
+    struct bin in;							\
     octet b[SZ_##W];							\
-    if (!PyArg_ParseTuple(arg, "s#:hashbuf" #w, &p, &sz)) goto end;	\
-    if (sz > MASK##n) TYERR("string too long");				\
+    if (!PyArg_ParseTuple(arg, "O&:hashbuf" #w, convbin, &in)) goto end; \
+    if (in.sz > MASK##n) TYERR("string too long");			\
     if (shake_check(me, 0)) goto end;					\
-    STORE##W(b, sz); shake_hash(SHAKE_H(me), b, sizeof(b));		\
-    shake_hash(SHAKE_H(me), p, sz);					\
+    STORE##W(b, in.sz); shake_hash(SHAKE_H(me), b, sizeof(b));		\
+    shake_hash(SHAKE_H(me), in.p, in.sz);				\
     RETURN_ME;								\
   end:									\
     return (0);								\
@@ -3115,12 +3101,12 @@ end:
 static PyObject *shakemeth_mask(PyObject *me, PyObject *arg)
 {
   PyObject *rc = 0;
-  char *p; Py_ssize_t sz;
+  struct bin in;
 
-  if (!PyArg_ParseTuple(arg, "s#:mask", &p, &sz)) goto end;
+  if (!PyArg_ParseTuple(arg, "O&:mask", convbin, &in)) goto end;
   if (shake_check(me, 1)) goto end;
-  rc = bytestring_pywrap(0, sz);
-  shake_mask(SHAKE_H(me), p, PyString_AS_STRING(rc), sz);
+  rc = bytestring_pywrap(0, in.sz);
+  shake_mask(SHAKE_H(me), in.p, PyString_AS_STRING(rc), in.sz);
 end:
   return (rc);
 }
@@ -3371,17 +3357,16 @@ typedef struct prp {
 static PyObject *gprp_pynew(PyTypeObject *ty, PyObject *arg, PyObject *kw)
 {
   static const char *const kwlist[] = { "key", 0 };
-  char *k;
-  Py_ssize_t sz;
+  struct bin k;
   const prpinfo *prp = GCPRP_PRP(ty);
   PyObject *me;
 
-  if (!PyArg_ParseTupleAndKeywords(arg, kw, "s#:new", KWLIST, &k, &sz))
+  if (!PyArg_ParseTupleAndKeywords(arg, kw, "O&:new", KWLIST, convbin, &k))
     goto end;
-  if (keysz(sz, prp->keysz) != sz) VALERR("bad key length");
+  if (keysz(k.sz, prp->keysz) != k.sz) VALERR("bad key length");
   me = (PyObject *)ty->tp_alloc(ty, 0);
   GPRP_PRP(me) = prp;
-  prp->init(GPRP_CTX(me), k, sz);
+  prp->init(GPRP_CTX(me), k.p, k.sz);
   Py_INCREF(me);
   return (me);
 end:
@@ -3417,28 +3402,26 @@ static PyObject *gcpget_blksz(PyObject *me, void *hunoz)
 
 static PyObject *gpmeth_encrypt(PyObject *me, PyObject *arg)
 {
-  char *p;
-  Py_ssize_t n;
+  struct bin m;
   PyObject *rc = 0;
 
-  if (!PyArg_ParseTuple(arg, "s#:encrypt", &p, &n)) goto end;
-  if (n != GPRP_PRP(me)->blksz) VALERR("incorrect block length");
-  rc = bytestring_pywrap(0, n);
-  GPRP_PRP(me)->eblk(GPRP_CTX(me), p, PyString_AS_STRING(rc));
+  if (!PyArg_ParseTuple(arg, "O&:encrypt", convbin, &m)) goto end;
+  if (m.sz != GPRP_PRP(me)->blksz) VALERR("incorrect block length");
+  rc = bytestring_pywrap(0, m.sz);
+  GPRP_PRP(me)->eblk(GPRP_CTX(me), m.p, PyString_AS_STRING(rc));
 end:
   return (rc);
 }
 
 static PyObject *gpmeth_decrypt(PyObject *me, PyObject *arg)
 {
-  char *p;
-  Py_ssize_t n;
+  struct bin c;
   PyObject *rc = 0;
 
-  if (!PyArg_ParseTuple(arg, "s#:decrypt", &p, &n)) goto end;
-  if (n != GPRP_PRP(me)->blksz) VALERR("incorrect block length");
-  rc = bytestring_pywrap(0, n);
-  GPRP_PRP(me)->dblk(GPRP_CTX(me), p, PyString_AS_STRING(rc));
+  if (!PyArg_ParseTuple(arg, "O&:decrypt", convbin, &c)) goto end;
+  if (c.sz != GPRP_PRP(me)->blksz) VALERR("incorrect block length");
+  rc = bytestring_pywrap(0, c.sz);
+  GPRP_PRP(me)->dblk(GPRP_CTX(me), c.p, PyString_AS_STRING(rc));
 end:
   return (rc);
 }