diff options
Diffstat (limited to 'crypto/ec/ecp_nistp256.c')
| -rw-r--r-- | crypto/ec/ecp_nistp256.c | 77 |
1 files changed, 40 insertions, 37 deletions
diff --git a/crypto/ec/ecp_nistp256.c b/crypto/ec/ecp_nistp256.c index ea63c10f49..a5887086c6 100644 --- a/crypto/ec/ecp_nistp256.c +++ b/crypto/ec/ecp_nistp256.c @@ -437,25 +437,25 @@ static void felem_shrink(smallfelem out, const felem in) /* As tmp[3] < 2^65, high is either 1 or 0 */ high <<= 63; high >>= 63; - /*- - * high is: - * all ones if the high word of tmp[3] is 1 - * all zeros if the high word of tmp[3] if 0 */ + /*- + * high is: + * all ones if the high word of tmp[3] is 1 + * all zeros if the high word of tmp[3] if 0 */ low = tmp[3]; mask = low >> 63; - /*- - * mask is: - * all ones if the MSB of low is 1 - * all zeros if the MSB of low if 0 */ + /*- + * mask is: + * all ones if the MSB of low is 1 + * all zeros if the MSB of low if 0 */ low &= bottom63bits; low -= kPrime3Test; /* if low was greater than kPrime3Test then the MSB is zero */ low = ~low; low >>= 63; - /*- - * low is: - * all ones if low was > kPrime3Test - * all zeros if low was <= kPrime3Test */ + /*- + * low is: + * all ones if low was > kPrime3Test + * all zeros if low was <= kPrime3Test */ mask = (mask & low) | high; tmp[0] -= mask & kPrime[0]; tmp[1] -= mask & kPrime[1]; @@ -795,17 +795,17 @@ static void felem_reduce(felem out, const longfelem in) felem_reduce_(out, in); - /*- - * out[0] > 2^100 - 2^36 - 2^4 - 3*2^64 - 3*2^96 - 2^64 - 2^96 > 0 - * out[1] > 2^100 - 2^64 - 7*2^96 > 0 - * out[2] > 2^100 - 2^36 + 2^4 - 5*2^64 - 5*2^96 > 0 - * out[3] > 2^100 - 2^36 + 2^4 - 7*2^64 - 5*2^96 - 3*2^96 > 0 - * - * out[0] < 2^100 + 2^64 + 7*2^64 + 5*2^96 < 2^101 - * out[1] < 2^100 + 3*2^64 + 5*2^64 + 3*2^97 < 2^101 - * out[2] < 2^100 + 5*2^64 + 2^64 + 3*2^65 + 2^97 < 2^101 - * out[3] < 2^100 + 7*2^64 + 7*2^96 + 3*2^64 < 2^101 - */ + /*- + * out[0] > 2^100 - 2^36 - 2^4 - 3*2^64 - 3*2^96 - 2^64 - 2^96 > 0 + * out[1] > 2^100 - 2^64 - 7*2^96 > 0 + * out[2] > 2^100 - 2^36 + 2^4 - 5*2^64 - 5*2^96 > 0 + * out[3] > 2^100 - 2^36 + 2^4 - 7*2^64 - 5*2^96 - 3*2^96 > 0 + * + * out[0] < 2^100 + 2^64 + 7*2^64 + 5*2^96 < 2^101 + * out[1] < 2^100 + 3*2^64 + 5*2^64 + 3*2^97 < 2^101 + * out[2] < 2^100 + 5*2^64 + 2^64 + 3*2^65 + 2^97 < 2^101 + * out[3] < 2^100 + 7*2^64 + 7*2^96 + 3*2^64 < 2^101 + */ } /*- @@ -824,17 +824,17 @@ static void felem_reduce_zero105(felem out, const longfelem in) felem_reduce_(out, in); - /*- - * out[0] > 2^105 - 2^41 - 2^9 - 2^71 - 2^103 - 2^71 - 2^103 > 0 - * out[1] > 2^105 - 2^71 - 2^103 > 0 - * out[2] > 2^105 - 2^41 + 2^9 - 2^71 - 2^103 > 0 - * out[3] > 2^105 - 2^41 + 2^9 - 2^71 - 2^103 - 2^103 > 0 - * - * out[0] < 2^105 + 2^71 + 2^71 + 2^103 < 2^106 - * out[1] < 2^105 + 2^71 + 2^71 + 2^103 < 2^106 - * out[2] < 2^105 + 2^71 + 2^71 + 2^71 + 2^103 < 2^106 - * out[3] < 2^105 + 2^71 + 2^103 + 2^71 < 2^106 - */ + /*- + * out[0] > 2^105 - 2^41 - 2^9 - 2^71 - 2^103 - 2^71 - 2^103 > 0 + * out[1] > 2^105 - 2^71 - 2^103 > 0 + * out[2] > 2^105 - 2^41 + 2^9 - 2^71 - 2^103 > 0 + * out[3] > 2^105 - 2^41 + 2^9 - 2^71 - 2^103 - 2^103 > 0 + * + * out[0] < 2^105 + 2^71 + 2^71 + 2^103 < 2^106 + * out[1] < 2^105 + 2^71 + 2^71 + 2^103 < 2^106 + * out[2] < 2^105 + 2^71 + 2^71 + 2^71 + 2^103 < 2^106 + * out[3] < 2^105 + 2^71 + 2^103 + 2^71 < 2^106 + */ } /* @@ -1099,7 +1099,8 @@ static void smallfelem_inv_contract(smallfelem out, const smallfelem in) * * Building on top of the field operations we have the operations on the * elliptic curve group itself. Points on the curve are represented in Jacobian - * coordinates */ + * coordinates + */ /*- * point_double calculates 2*(x_in, y_in, z_in) @@ -1108,7 +1109,8 @@ static void smallfelem_inv_contract(smallfelem out, const smallfelem in) * http://hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-3.html#doubling-dbl-2001-b * * Outputs can equal corresponding inputs, i.e., x_out == x_in is allowed. - * while x_out == y_in is not (maybe this works, but it's not tested). */ + * while x_out == y_in is not (maybe this works, but it's not tested). + */ static void point_double(felem x_out, felem y_out, felem z_out, const felem x_in, const felem y_in, const felem z_in) @@ -1239,7 +1241,8 @@ static void copy_small_conditional(felem out, const smallfelem in, limb mask) * This function includes a branch for checking whether the two input points * are equal, (while not equal to the point at infinity). This case never * happens during single point multiplication, so there is no timing leak for - * ECDH or ECDSA signing. */ + * ECDH or ECDSA signing. + */ static void point_add(felem x3, felem y3, felem z3, const felem x1, const felem y1, const felem z1, const int mixed, const smallfelem x2, |