diff options
| -rw-r--r-- | stm32_driver/ecdsa256_driver_sample.c | 30 |
1 files changed, 15 insertions, 15 deletions
diff --git a/stm32_driver/ecdsa256_driver_sample.c b/stm32_driver/ecdsa256_driver_sample.c index fcfd3ae..1950491 100644 --- a/stm32_driver/ecdsa256_driver_sample.c +++ b/stm32_driver/ecdsa256_driver_sample.c @@ -122,22 +122,22 @@ int main() ok = ok && test_p256_multiplier(p256_n, p256_z, p256_z); /* O = n * G */ - ok = ok && test_p256_multiplier(p256_n1, p256_gx, p256_gy); /* G = (n + 1) * G */ + ok = ok && test_p256_multiplier(p256_n1, p256_gx, p256_gy); /* G = (n + 1) * G */ - // - // The following two vectors test the virtually never taken path in the curve point - // addition routine when both input points are the same. During the first test (2 * G) - // the double of the base point is computed at the second doubling step of the multiplication - // algorithm, which does not require any special handling. During the second test the - // precomputed double of the base point (stored in internal read-only memory) is returned, - // because after doubling of G * ((n + 1) / 2) we get G * (n + 1) = G. The adder then has to - // compute G + G for which the formulae don't work, and special handling is required. The two - // test vectors verify that the hardcoded double of the base point matches the one computed - // on the fly. Note that in practice one should never be multiplying by anything larger than (n-1), - // because both the secret key and the per-message (random) number must be from [1, n-1]. - // - ok = ok && test_p256_multiplier(p256_2, p256_hx, p256_hy); /* H = 2 * G */ - ok = ok && test_p256_multiplier(p256_n2, p256_hx, p256_hy); /* H = (n + 2) * G */ + // + // The following two vectors test the virtually never taken path in the curve point + // addition routine when both input points are the same. During the first test (2 * G) + // the double of the base point is computed at the second doubling step of the multiplication + // algorithm, which does not require any special handling. During the second test the + // precomputed double of the base point (stored in internal read-only memory) is returned, + // because after doubling of G * ((n + 1) / 2) we get G * (n + 1) = G. The adder then has to + // compute G + G for which the formulae don't work, and special handling is required. The two + // test vectors verify that the hardcoded double of the base point matches the one computed + // on the fly. Note that in practice one should never be multiplying by anything larger than (n-1), + // because both the secret key and the per-message (random) number must be from [1, n-1]. + // + ok = ok && test_p256_multiplier(p256_2, p256_hx, p256_hy); /* H = 2 * G */ + ok = ok && test_p256_multiplier(p256_n2, p256_hx, p256_hy); /* H = (n + 2) * G */ if (!ok) { led_off(LED_GREEN); |