tls: shrink p256_base
function old new delta
curve_P256_compute_pubkey_and_premaster 196 291 +95
static.base_y - 40 +40
static.base_x - 40 +40
p256_base 244 - -244
------------------------------------------------------------------------------
(add/remove: 2/1 grow/shrink: 1/0 up/down: 175/-244) Total: -69 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/networking/tls_sp_c32.c b/networking/tls_sp_c32.c
index 8059f6e..64c53b0 100644
--- a/networking/tls_sp_c32.c
+++ b/networking/tls_sp_c32.c
@@ -72,18 +72,6 @@
#define p256_mp_mod ((sp_digit)0x000001)
-/* The base point of curve P256. */
-static const sp_point p256_base = {
- /* X ordinate */
- { 0x098c296,0x04e5176,0x33a0f4a,0x204b7ac,0x277037d,0x0e9103c,0x3ce6e56,0x1091fe2,0x1f2e12c,0x01ac5f4 },
- /* Y ordinate */
- { 0x3bf51f5,0x1901a0d,0x1ececbb,0x15dacc5,0x22bce33,0x303e785,0x27eb4a7,0x1fe6e3b,0x2e2fe1a,0x013f8d0 },
- /* Z ordinate */
- { 0x0000001,0x0000000,0x0000000,0x0000000,0x0000000,0x0000000,0x0000000,0x0000000,0x0000000,0x0000000 },
- /* infinity */
- 0
-};
-
/* Write r as big endian to byte aray.
* Fixed length number of bytes written: 32
*
@@ -798,6 +786,24 @@
*/
static void sp_256_ecc_mulmod_base_10(sp_point* r, sp_digit* k /*, int map*/)
{
+ /* Since this function is called only once, save space:
+ * don't have "static const sp_point p256_base = {...}",
+ * it would have more zeros than data.
+ */
+ static const sp_digit base_x[] = {
+ 0x098c296,0x04e5176,0x33a0f4a,0x204b7ac,0x277037d,0x0e9103c,0x3ce6e56,0x1091fe2,0x1f2e12c,0x01ac5f4
+ };
+ static const sp_digit base_y[] = {
+ 0x3bf51f5,0x1901a0d,0x1ececbb,0x15dacc5,0x22bce33,0x303e785,0x27eb4a7,0x1fe6e3b,0x2e2fe1a,0x013f8d0
+ };
+ sp_point p256_base;
+
+ memset(&p256_base, 0, sizeof(p256_base));
+ memcpy(p256_base.x, base_x, sizeof(base_x));
+ memcpy(p256_base.y, base_y, sizeof(base_y));
+ p256_base.z[0] = 1;
+ /*p256_base.infinity = 0;*/
+
sp_256_ecc_mulmod_10(r, &p256_base, k /*, map*/);
}