X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~mdw/git/tripe/blobdiff_plain/b2a72eca5851cfbd4146dd7e65867cd939b8f623..4155aec42e2aa48af1ebe8f1197f58e2f5830ccf:/server/keymgmt.c?ds=sidebyside

diff --git a/server/keymgmt.c b/server/keymgmt.c
index 0ef633c0..d80b81e8 100644
--- a/server/keymgmt.c
+++ b/server/keymgmt.c
@@ -42,135 +42,124 @@ typedef struct kgops {
   int (*loadpub)(key_data *, kdata *, dstr *, dstr *);
 } kgops;
 
-/* --- Diffie-Hellman --- */
-
-static int kgdh_priv(key_data *d, kdata *kd, dstr *t, dstr *e)
-{
-  key_packstruct kps[DH_PRIVFETCHSZ];
-  key_packdef *kp;
-  dh_priv dp;
-  int rc;
-
-  kp = key_fetchinit(dh_privfetch, kps, &dp);
-  if ((rc = key_unpack(kp, d, t)) != 0) {
-    a_format(e, "unpack-failed", "%s", key_strerror(rc), A_END);
-    goto fail_0;
-  }
-  kd->g = group_prime(&dp.dp);
-  kd->kpriv = MP_COPY(dp.x);
-  rc = 0;
-  goto done;
-fail_0:
-  rc = -1;
-done:
-  key_fetchdone(kp);
-  return (rc);
-}
-
-static int kgdh_pub(key_data *d, kdata *kd, dstr *t, dstr *e)
-{
-  key_packstruct kps[DH_PUBFETCHSZ];
-  key_packdef *kp;
-  dh_pub dp;
-  int rc;
-
-  kp = key_fetchinit(dh_pubfetch, kps, &dp);
-  if ((rc = key_unpack(kp, d, t)) != 0) {
-    a_format(e, "unpack-failed", "%s", key_strerror(rc), A_END);
-    goto fail_0;
-  }
-  kd->g = group_prime(&dp.dp);
-  kd->kpub = G_CREATE(kd->g);
-  if (G_FROMINT(kd->g, kd->kpub, dp.y)) {
-    a_format(e, "bad-public-vector", A_END);
-    goto fail_1;
-  }
-  rc = 0;
-  goto done;
-fail_1:
-  G_DESTROY(kd->g, kd->kpub);
-  G_DESTROYGROUP(kd->g);
-fail_0:
-  rc = -1;
-done:
-  key_fetchdone(kp);
-  return (rc);
-}
-
-static const kgops kgdh_ops = { "dh", kgdh_priv, kgdh_pub };
-
-/* --- Elliptic curve --- */
-
-static int kgec_priv(key_data *d, kdata *kd, dstr *t, dstr *e)
-{
-  key_packstruct kps[EC_PRIVFETCHSZ];
-  key_packdef *kp;
-  ec_priv ep;
-  ec_info ei;
-  const char *err;
-  int rc;
+/* --- @KLOAD@ --- *
+ *
+ * Arguments:	@ty@, @TY@ = key type name (lower- and upper-case)
+ *		@which@, @WHICH@ = `pub' or `priv' (and upper-case)
+ *		@setgroup@ = code to initialize @kd->g@
+ *		@setpriv@ = code to initialize @kd->kpriv@
+ *		@setpub@ = code to initialize @kd->kpub@
+ *
+ * Use:		Generates the body of one of the (rather tedious) key loading
+ *		functions.  See the description of @KEYTYPES@ below for the
+ *		details.
+ */
 
-  kp = key_fetchinit(ec_privfetch, kps, &ep);
-  if ((rc = key_unpack(kp, d, t)) != 0) {
-    a_format(e, "unpack-failed", "%s", key_strerror(rc), A_END);
-    goto fail_0;
-  }
-  if ((err = ec_getinfo(&ei, ep.cstr)) != 0) {
-    a_format(e, "decode-failed", "%s", err, A_END);
-    goto fail_0;
-  }
-  kd->g = group_ec(&ei);
-  kd->kpriv = MP_COPY(ep.x);
-  rc = 0;
-  goto done;
-fail_0:
-  rc = -1;
-done:
-  key_fetchdone(kp);
-  return (rc);
+#define KLOAD(ty, TY, which, WHICH, setgroup, setpriv, setpub)		\
+static int kg##ty##_##which(key_data *d, kdata *kd, dstr *t, dstr *e)	\
+{									\
+  key_packstruct kps[TY##_##WHICH##FETCHSZ];				\
+  key_packdef *kp;							\
+  ty##_##which p;							\
+  int rc;								\
+									\
+  /* --- Initialize things we've not set up yet --- */			\
+									\
+  kd->g = 0; kd->kpub = 0;						\
+									\
+  /* --- Unpack the key --- */						\
+									\
+  kp = key_fetchinit(ty##_##which##fetch, kps, &p);			\
+  if ((rc = key_unpack(kp, d, t)) != 0) {				\
+    a_format(e, "unpack-failed", "%s", key_strerror(rc), A_END);	\
+    goto fail;								\
+  }									\
+									\
+  /* --- Extract the pieces of the key --- */				\
+									\
+  setgroup;								\
+  setpriv;								\
+  kd->kpub = G_CREATE(kd->g);						\
+  setpub;								\
+									\
+  /* --- We win --- */							\
+									\
+  rc = 0;								\
+  goto done;								\
+									\
+fail:									\
+  if (kd->kpub) G_DESTROY(kd->g, kd->kpub);				\
+  if (kd->g) G_DESTROYGROUP(kd->g);					\
+  rc = -1;								\
+									\
+done:									\
+  key_fetchdone(kp);							\
+  return (rc);								\
 }
 
-static int kgec_pub(key_data *d, kdata *kd, dstr *t, dstr *e)
-{
-  key_packstruct kps[EC_PUBFETCHSZ];
-  key_packdef *kp;
-  ec_pub ep;
-  ec_info ei;
-  const char *err;
-  int rc;
+/* --- @KEYTYPES@ --- *
+ *
+ * A list of the various key types, and how to unpack them.  Each entry in
+ * the list has the form
+ *
+ *	_(ty, TY, setgroup, setpriv, setpub)
+ *
+ * The @ty@ and @TY@ are lower- and upper-case versions of the key type name,
+ * and there should be @key_fetchdef@s called @ty_{priv,pub}fetch@.
+ *
+ * The @setgroup@, @setpriv@ and @setpub@ items are code fragments which are
+ * passed to @KLOAD@ to build appropriate key-loading methods.  By the time
+ * these code fragments are run, the key has been unpacked from the incoming
+ * key data using @ty_whichfetch@ into a @ty_which@ structure named @p@.
+ * They can report errors by writing an appropriate token sequence to @e@ and
+ * jumping to @fail@.
+ */
 
-  kp = key_fetchinit(ec_pubfetch, kps, &ep);
-  if ((rc = key_unpack(kp, d, t)) != 0) {
-    a_format(e, "unpack-failed", "%s", key_strerror(rc), A_END);
-    goto fail_0;
-  }
-  if ((err = ec_getinfo(&ei, ep.cstr)) != 0) {
-    a_format(e, "decode-failed", "%s", err, A_END);
-    goto fail_0;
-  }
-  kd->g = group_ec(&ei);
-  kd->kpub = G_CREATE(kd->g);
-  if (G_FROMEC(kd->g, kd->kpub, &ep.p)) {
-    a_format(e, "bad-public-vector", A_END);
-    goto fail_1;
-  }
-  rc = 0;
-  goto done;
-fail_1:
-  G_DESTROY(kd->g, kd->kpub);
-  G_DESTROYGROUP(kd->g);
-fail_0:
-  rc = -1;
-done:
-  key_fetchdone(kp);
-  return (rc);
-}
+#define KEYTYPES(_)							\
+									\
+  /* --- Diffie-Hellman --- */						\
+									\
+  _(dh, DH,								\
+    { kd->g = group_prime(&p.dp); },					\
+    { kd->kpriv = MP_COPY(p.x); },					\
+    { if (G_FROMINT(kd->g, kd->kpub, p.y)) {				\
+	a_format(e, "bad-public-vector", A_END);			\
+	goto fail;							\
+      }									\
+    })									\
+									\
+  /* --- Elliptic curves --- */						\
+									\
+  _(ec, EC,								\
+    { ec_info ei; const char *err;					\
+      if ((err = ec_getinfo(&ei, p.cstr)) != 0) {			\
+	a_format(e, "decode-failed", "%s", err, A_END);			\
+	goto fail;							\
+      }									\
+      kd->g = group_ec(&ei);						\
+    },									\
+    { kd->kpriv = MP_COPY(p.x); },					\
+    { if (G_FROMEC(kd->g, kd->kpub, &p.p)) {				\
+	a_format(e, "bad-public-vector", A_END);			\
+	goto fail;							\
+      }									\
+    })
 
-static const kgops kgec_ops = { "ec", kgec_priv, kgec_pub };
+#define KEYTYPE_DEF(ty, TY, setgroup, setpriv, setpub)			\
+  KLOAD(ty, TY, priv, PRIV, setgroup, setpriv,				\
+	{ G_EXP(kd->g, kd->kpub, kd->g->g, kd->kpriv); })		\
+  KLOAD(ty, TY, pub, PUB, setgroup, { }, setpub)			\
+  static const kgops kg##ty##_ops = { #ty, kg##ty##_priv, kg##ty##_pub };
+KEYTYPES(KEYTYPE_DEF)
 
 /* --- Table of supported key types --- */
 
-static const kgops *kgtab[] = { &kgdh_ops, &kgec_ops, 0 };
+static const kgops *kgtab[] = {
+#define KEYTYPE_ENTRY(ty, TY, setgroup, setpriv, setpub) &kg##ty##_ops,
+  KEYTYPES(KEYTYPE_ENTRY)
+#undef KEYTYPE_ENTRY
+  0
+};
 
 /*----- Algswitch stuff ---------------------------------------------------*/
 
@@ -404,12 +393,11 @@ static int kh_loadpriv(const kgops *ko, key_data *d, kdata *kd,
     a_format(e, "bad-group", "%s", err, A_END);
     goto fail_1;
   }
-  kd->kpub = G_CREATE(kd->g);
-  G_EXP(kd->g, kd->kpub, kd->g->g, kd->kpriv);
   return (0);
 
 fail_1:
   mp_drop(kd->kpriv);
+  G_DESTROY(kd->g, kd->kpub);
   G_DESTROYGROUP(kd->g);
 fail_0:
   return (-1);