Define accessor functions to get address of ecc curve structs.

ChangeLog

 2017-04-09  Niels Möller  <nisse@lysator.liu.se>
 
+	* ecc-curve.h (nettle_get_secp_192r1, nettle_get_secp_224r1)
+	(nettle_get_secp_256r1, nettle_get_secp_384r1)
+	(nettle_get_secp_521r1): New functions, returning a pointer to
+	corresponding structure.
+	(nettle_secp_192r1, nettle_secp_224r1, nettle_secp_256r1)
+	(nettle_secp_384r1, nettle_secp_521r1): Redefined as macros,
+	calling the corresponding function.
+
 	* nettle-meta.h (nettle_ciphers, nettle_aeads, nettle_armors): New
 	macros, analogous to below change to nettle_hashes.
 

ecc-192.c

@@ -110,7 +110,7 @@ ecc_192_modp (const struct ecc_modulo *m UNUSED, mp_limb_t *rp)
 #define ecc_192_modp ecc_mod
 #endif
 
-const struct ecc_curve nettle_secp_192r1 =
+const struct ecc_curve _nettle_secp_192r1 =
 {
   {
     192,
@@ -172,3 +172,7 @@ const struct ecc_curve nettle_secp_192r1 =
   ecc_table
 };
 
+const struct ecc_curve *nettle_get_secp_192r1(void)
+{
+  return &_nettle_secp_192r1;
+}

ecc-224.c

@@ -62,7 +62,7 @@ ecc_224_modp (const struct ecc_modulo *m, mp_limb_t *rp);
 # error Configuration error
 #endif
 
-const struct ecc_curve nettle_secp_224r1 =
+const struct ecc_curve _nettle_secp_224r1 =
 {
   {
     224,
@@ -123,3 +123,8 @@ const struct ecc_curve nettle_secp_224r1 =
   ecc_unit,
   ecc_table
 };
+
+const struct ecc_curve *nettle_get_secp_224r1(void)
+{
+  return &_nettle_secp_224r1;
+}

ecc-256.c

@@ -239,7 +239,7 @@ ecc_256_modq (const struct ecc_modulo *q, mp_limb_t *rp)
 #error Unsupported parameters
 #endif
 
-const struct ecc_curve nettle_secp_256r1 =
+const struct ecc_curve _nettle_secp_256r1 =
 {
   {
     256,
@@ -300,3 +300,8 @@ const struct ecc_curve nettle_secp_256r1 =
   ecc_unit,
   ecc_table
 };
+
+const struct ecc_curve *nettle_get_secp_256r1(void)
+{
+  return &_nettle_secp_256r1;
+}

ecc-384.c

@@ -147,7 +147,7 @@ ecc_384_modp (const struct ecc_modulo *p, mp_limb_t *rp)
 #define ecc_384_modp ecc_mod
 #endif
   
-const struct ecc_curve nettle_secp_384r1 =
+const struct ecc_curve _nettle_secp_384r1 =
 {
   {
     384,
@@ -208,3 +208,8 @@ const struct ecc_curve nettle_secp_384r1 =
   ecc_unit,
   ecc_table
 };
+
+const struct ecc_curve *nettle_get_secp_384r1(void)
+{
+  return &_nettle_secp_384r1;
+}

ecc-521.c

@@ -75,7 +75,7 @@ ecc_521_modp (const struct ecc_modulo *m UNUSED, mp_limb_t *rp)
 }
 #endif
 
-const struct ecc_curve nettle_secp_521r1 =
+const struct ecc_curve _nettle_secp_521r1 =
 {
   {
     521,
@@ -137,3 +137,7 @@ const struct ecc_curve nettle_secp_521r1 =
   ecc_table
 };
 
+const struct ecc_curve *nettle_get_secp_521r1(void)
+{
+  return &_nettle_secp_521r1;
+}

ecc-curve.h

@@ -41,11 +41,26 @@ extern "C" {
 /* The contents of this struct is internal. */
 struct ecc_curve;
 
-extern const struct ecc_curve nettle_secp_192r1;
-extern const struct ecc_curve nettle_secp_224r1;
-extern const struct ecc_curve nettle_secp_256r1;
-extern const struct ecc_curve nettle_secp_384r1;
-extern const struct ecc_curve nettle_secp_521r1;
+#ifdef __GNUC__
+#define NETTLE_PURE __attribute__((pure))
+#else
+#define NETTLE_PURE
+#endif
+
+const struct ecc_curve * NETTLE_PURE nettle_get_secp_192r1(void);
+const struct ecc_curve * NETTLE_PURE nettle_get_secp_224r1(void);
+const struct ecc_curve * NETTLE_PURE nettle_get_secp_256r1(void);
+const struct ecc_curve * NETTLE_PURE nettle_get_secp_384r1(void);
+const struct ecc_curve * NETTLE_PURE nettle_get_secp_521r1(void);
+
+#undef NETTLE_PURE
+
+/* For backwards compatibility */
+#define nettle_secp_192r1 (*nettle_get_secp_192r1())
+#define nettle_secp_224r1 (*nettle_get_secp_224r1())
+#define nettle_secp_256r1 (*nettle_get_secp_256r1())
+#define nettle_secp_384r1 (*nettle_get_secp_384r1())
+#define nettle_secp_521r1 (*nettle_get_secp_521r1())
 
 #ifdef __cplusplus
 }

ecc-internal.h

@@ -73,6 +73,12 @@
 #define sec_modinv _nettle_sec_modinv
 #define curve25519_eh_to_x _nettle_curve25519_eh_to_x
 
+extern const struct ecc_curve _nettle_secp_192r1;
+extern const struct ecc_curve _nettle_secp_224r1;
+extern const struct ecc_curve _nettle_secp_256r1;
+extern const struct ecc_curve _nettle_secp_384r1;
+extern const struct ecc_curve _nettle_secp_521r1;
+
 /* Keep this structure internal for now. It's misnamed (since it's
    really implementing the equivalent twisted Edwards curve, with
    different coordinates). And we're not quite ready to provide

examples/ecc-benchmark.c

@@ -330,12 +330,12 @@ bench_curve (const struct ecc_curve *ecc)
 }
 
 const struct ecc_curve * const curves[] = {
-  &nettle_secp_192r1,
-  &nettle_secp_224r1,
+  &_nettle_secp_192r1,
+  &_nettle_secp_224r1,
   &_nettle_curve25519,
-  &nettle_secp_256r1,
-  &nettle_secp_384r1,
-  &nettle_secp_521r1,
+  &_nettle_secp_256r1,
+  &_nettle_secp_384r1,
+  &_nettle_secp_521r1,
 };
 
 #define numberof(x)  (sizeof (x) / sizeof ((x)[0]))

testsuite/testutils.c

@@ -1212,11 +1212,11 @@ test_dsa_key(const struct dsa_params *params,
 }
 
 const struct ecc_curve * const ecc_curves[] = {
-  &nettle_secp_192r1,
-  &nettle_secp_224r1,
-  &nettle_secp_256r1,
-  &nettle_secp_384r1,
-  &nettle_secp_521r1,
+  &_nettle_secp_192r1,
+  &_nettle_secp_224r1,
+  &_nettle_secp_256r1,
+  &_nettle_secp_384r1,
+  &_nettle_secp_521r1,
   &_nettle_curve25519,
   NULL
 };