New implementation of Curve25519 (using multiplications of words of 15 bits or so...

[BearSSL] / src / ec / ec_c25519_i15.c

diff --git a/src/ec/ec_c25519_i15.c b/src/ec/ec_c25519_i15.c
index 79560ae..6e4c4f8 100644 (file)
--- a/src/ec/ec_c25519_i15.c
+++ b/src/ec/ec_c25519_i15.c
@@ -46,6 +46,27 @@ static const uint16_t C255_R2[] = {
        0x0000
 };
 
+/* obsolete
+#include <stdio.h>
+#include <stdlib.h>
+static void
+print_int_mont(const char *name, const uint16_t *x)
+{
+       uint16_t y[18];
+       unsigned char tmp[32];
+       size_t u;
+
+       printf("%s = ", name);
+       memcpy(y, x, sizeof y);
+       br_i15_from_monty(y, C255_P, P0I);
+       br_i15_encode(tmp, sizeof tmp, y);
+       for (u = 0; u < sizeof tmp; u ++) {
+               printf("%02X", tmp[u]);
+       }
+       printf("\n");
+}
+*/
+
 static const uint16_t C255_A24[] = {
        0x0110,
        0x45D3, 0x0046, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
@@ -194,6 +215,10 @@ api_mul(unsigned char *G, size_t Glen,
        k[31] &= 0x7F;
        k[31] |= 0x40;
 
+       /* obsolete
+       print_int_mont("x1", x1);
+       */
+
        swap = 0;
        for (i = 254; i >= 0; i --) {
                uint32_t kt;
@@ -204,6 +229,13 @@ api_mul(unsigned char *G, size_t Glen,
                cswap(z2, z3, swap);
                swap = kt;
 
+               /* obsolete
+               print_int_mont("x2", x2);
+               print_int_mont("z2", z2);
+               print_int_mont("x3", x3);
+               print_int_mont("z3", z3);
+               */
+
                c255_add(a, x2, z2);
                c255_mul(aa, a, a);
                c255_sub(b, x2, z2);
@@ -213,6 +245,19 @@ api_mul(unsigned char *G, size_t Glen,
                c255_sub(d, x3, z3);
                c255_mul(da, d, a);
                c255_mul(cb, c, b);
+
+               /* obsolete
+               print_int_mont("a ", a);
+               print_int_mont("aa", aa);
+               print_int_mont("b ", b);
+               print_int_mont("bb", bb);
+               print_int_mont("e ", e);
+               print_int_mont("c ", c);
+               print_int_mont("d ", d);
+               print_int_mont("da", da);
+               print_int_mont("cb", cb);
+               */
+
                c255_add(x3, da, cb);
                c255_mul(x3, x3, x3);
                c255_sub(z3, da, cb);
@@ -222,6 +267,13 @@ api_mul(unsigned char *G, size_t Glen,
                c255_mul(z2, C255_A24, e);
                c255_add(z2, z2, aa);
                c255_mul(z2, e, z2);
+
+               /* obsolete
+               print_int_mont("x2", x2);
+               print_int_mont("z2", z2);
+               print_int_mont("x3", x3);
+               print_int_mont("z3", z3);
+               */
        }
        cswap(x2, x3, swap);
        cswap(z2, z3, swap);