From: Mark Wooding <mdw@distorted.org.uk>
Date: Thu, 11 May 2017 09:42:15 +0000 (+0100)
Subject: pubkey.c: Support the `ed2559ctx' signature scheme from RFC8032.
X-Git-Tag: 1.2.0~5
X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~mdw/git/catacomb-python/commitdiff_plain/5c4c02314ca241c437b28f301658fee743323739

pubkey.c: Support the `ed2559ctx' signature scheme from RFC8032.

Main difference is the addition of a personalization string.

In the wrapper classes, forward unknown keyword arguments on to the
underlying implementation.
---

diff --git a/catacomb.c b/catacomb.c
index 9c83c9d..9e3b9cb 100644
--- a/catacomb.c
+++ b/catacomb.c
@@ -48,6 +48,7 @@ static const struct nameval consts[] = {
   C(X25519_KEYSZ), C(X25519_PUBSZ), C(X25519_OUTSZ),
   C(X448_KEYSZ), C(X448_PUBSZ), C(X448_OUTSZ),
   C(ED25519_KEYSZ), C(ED25519_PUBSZ), C(ED25519_SIGSZ),
+    C(ED25519_MAXPERSOSZ),
 #define ENTRY(tag, val, str) C(KERR_##tag),
   KEY_ERRORS(ENTRY)
 #undef ENTRY
diff --git a/catacomb/__init__.py b/catacomb/__init__.py
index b9818e7..4840eef 100644
--- a/catacomb/__init__.py
+++ b/catacomb/__init__.py
@@ -901,14 +901,14 @@ class _EdDSAPriv (_BasePriv, _EdDSAPub):
 class Ed25519Pub (_EdDSAPub):
   _PUBSZ = KeySZSet(ED25519_PUBSZ)
   _HASH = sha512
-  def verify(me, msg, sig):
-    return ed25519_verify(me.pub, msg, sig)
+  def verify(me, msg, sig, **kw):
+    return ed25519_verify(me.pub, msg, sig, **kw)
 
 class Ed25519Priv (_EdDSAPriv, Ed25519Pub):
   _KEYSZ = KeySZAny(ED25519_KEYSZ)
   def _pubkey(me, priv): return ed25519_pubkey(priv)
-  def sign(me, msg):
-    return ed25519_sign(me.priv, msg, pub = me.pub)
+  def sign(me, msg, **kw):
+    return ed25519_sign(me.priv, msg, pub = me.pub, **kw)
 
 ###--------------------------------------------------------------------------
 ### Built-in named curves and prime groups.
diff --git a/pubkey.c b/pubkey.c
index 642da3e..7374429 100644
--- a/pubkey.c
+++ b/pubkey.c
@@ -1164,9 +1164,9 @@ XDHS(DEFXDH)
 /*----- Ed25519 and related algorithms ------------------------------------*/
 
 #define EDDSAS(_)							\
-  _(ED25519, ed25519)
+  _(ED25519, ed25519, -1, ctx)
 
-#define DEFEDDSA(ED, ed)						\
+#define DEFEDDSA(ED, ed, phdflt, sigver)				\
 									\
   static PyObject *meth_##ed##_pubkey(PyObject *me, PyObject *arg)	\
   {									\
@@ -1185,21 +1185,26 @@ XDHS(DEFXDH)
   static PyObject *meth_##ed##_sign(PyObject *me, PyObject *arg,	\
 				    PyObject *kw)			\
   {									\
-    const char *k, *p = 0, *m;						\
-    Py_ssize_t ksz, psz, msz;						\
+    const char *k, *p = 0, *c = 0, *m;					\
+    Py_ssize_t ksz, psz, csz = 0, msz;					\
+    int ph = phdflt;							\
     PyObject *rc = 0;							\
     octet pp[ED##_PUBSZ];						\
-    char *kwlist[] = { "key", "msg", "pub", 0 };			\
+    char *kwlist[] = { "key", "msg", "pub", "perso", "phflag", 0 };	\
     if (!PyArg_ParseTupleAndKeywords(arg, kw,				\
-				     "s#s#|s#:" #ed "_sign",		\
+				     "s#s#|s#s#O&:" #ed "_sign",	\
 				     kwlist,				\
-				     &k, &ksz, &m, &msz, &p, &psz))	\
+				     &k, &ksz, &m, &msz, &p, &psz,	\
+				     &c, &csz, convbool, &ph))		\
       goto end;								\
     if (p && psz != ED##_PUBSZ) VALERR("bad public length");		\
+    if (c && csz > ED##_MAXPERSOSZ)					\
+      VALERR("personalization string too long");			\
+    if (c && ph == -1) ph = 0;						\
     if (!p) { p = (const char *)pp; ed##_pubkey(pp, k, ksz); }		\
     rc = bytestring_pywrap(0, ED##_SIGSZ);				\
-    ed##_sign((octet *)PyString_AS_STRING(rc), k, ksz,			\
-	      (const octet *)p, m, msz);				\
+    ed##sigver##_sign((octet *)PyString_AS_STRING(rc), k, ksz,		\
+		      (const octet *)p, ph, c, csz, m, msz);		\
     return (rc);							\
   end:									\
     return (0);								\
@@ -1208,19 +1213,24 @@ XDHS(DEFXDH)
   static PyObject *meth_##ed##_verify(PyObject *me,			\
 				      PyObject *arg, PyObject *kw)	\
   {									\
-    const char *p, *m, *s;						\
-    Py_ssize_t psz, msz, ssz;						\
+    const char *p, *c = 0, *m, *s;					\
+    Py_ssize_t psz, csz = 0, msz, ssz;					\
+    int ph = phdflt;							\
     PyObject *rc = 0;							\
-    char *kwlist[] = { "pub", "msg", "sig", 0 };			\
+    char *kwlist[] = { "pub", "msg", "sig", "perso", "phflag", 0 };	\
     if (!PyArg_ParseTupleAndKeywords(arg, kw,				\
-				     "s#s#s#:" #ed "_verify",		\
+				     "s#s#s#|s#O&:" #ed "_verify",	\
 				     kwlist,				\
-				     &p, &psz, &m, &msz, &s, &ssz))	\
+				     &p, &psz, &m, &msz, &s, &ssz,	\
+				     &c, &csz, convbool, &ph))		\
       goto end;								\
     if (psz != ED##_PUBSZ) VALERR("bad public length");			\
     if (ssz != ED##_SIGSZ) VALERR("bad signature length");		\
-    rc = getbool(!ed##_verify((const octet *)p,				\
-			      m, msz, (const octet *)s));		\
+    if (c && csz > ED##_MAXPERSOSZ)					\
+      VALERR("personalization string too long");			\
+    if (c && ph == -1) ph = 0;						\
+    rc = getbool(!ed##sigver##_verify((const octet *)p, ph, c, csz,	\
+				      m, msz, (const octet *)s));	\
     return (rc);							\
   end:									\
     return (0);								\
@@ -1247,7 +1257,7 @@ generate(NBITS, [event = pgen_nullev, rng = rand, nsteps = 0]) -> R")
 " #x "(KEY, PUBLIC) -> SHARED")
   XDHS(DEFMETH)
 #undef DEFMETH
-#define DEFMETH(ED, ed)							\
+#define DEFMETH(ED, ed, phdflt, sigver)					\
   METH  (ed##_pubkey,			"\
 " #ed "_pubkey(KEY) -> PUBLIC")						\
   KWMETH(ed##_sign,			"\