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-rw-r--r--nss/lib/freebl/ecl/ecp_521.c178
1 files changed, 89 insertions, 89 deletions
diff --git a/nss/lib/freebl/ecl/ecp_521.c b/nss/lib/freebl/ecl/ecp_521.c
index f70c2f4..6ca0dbb 100644
--- a/nss/lib/freebl/ecl/ecp_521.c
+++ b/nss/lib/freebl/ecl/ecp_521.c
@@ -10,76 +10,76 @@
#define ECP521_DIGITS ECL_CURVE_DIGITS(521)
/* Fast modular reduction for p521 = 2^521 - 1. a can be r. Uses
- * algorithm 2.31 from Hankerson, Menezes, Vanstone. Guide to
+ * algorithm 2.31 from Hankerson, Menezes, Vanstone. Guide to
* Elliptic Curve Cryptography. */
static mp_err
ec_GFp_nistp521_mod(const mp_int *a, mp_int *r, const GFMethod *meth)
{
- mp_err res = MP_OKAY;
- int a_bits = mpl_significant_bits(a);
- unsigned int i;
-
- /* m1, m2 are statically-allocated mp_int of exactly the size we need */
- mp_int m1;
-
- mp_digit s1[ECP521_DIGITS] = { 0 };
-
- MP_SIGN(&m1) = MP_ZPOS;
- MP_ALLOC(&m1) = ECP521_DIGITS;
- MP_USED(&m1) = ECP521_DIGITS;
- MP_DIGITS(&m1) = s1;
-
- if (a_bits < 521) {
- if (a==r) return MP_OKAY;
- return mp_copy(a, r);
- }
- /* for polynomials larger than twice the field size or polynomials
- * not using all words, use regular reduction */
- if (a_bits > (521*2)) {
- MP_CHECKOK(mp_mod(a, &meth->irr, r));
- } else {
-#define FIRST_DIGIT (ECP521_DIGITS-1)
- for (i = FIRST_DIGIT; i < MP_USED(a)-1; i++) {
- s1[i-FIRST_DIGIT] = (MP_DIGIT(a, i) >> 9)
- | (MP_DIGIT(a, 1+i) << (MP_DIGIT_BIT-9));
- }
- s1[i-FIRST_DIGIT] = MP_DIGIT(a, i) >> 9;
-
- if ( a != r ) {
- MP_CHECKOK(s_mp_pad(r,ECP521_DIGITS));
- for (i = 0; i < ECP521_DIGITS; i++) {
- MP_DIGIT(r,i) = MP_DIGIT(a, i);
- }
- }
- MP_USED(r) = ECP521_DIGITS;
- MP_DIGIT(r,FIRST_DIGIT) &= 0x1FF;
-
- MP_CHECKOK(s_mp_add(r, &m1));
- if (MP_DIGIT(r, FIRST_DIGIT) & 0x200) {
- MP_CHECKOK(s_mp_add_d(r,1));
- MP_DIGIT(r,FIRST_DIGIT) &= 0x1FF;
- } else if (s_mp_cmp(r, &meth->irr) == 0) {
- mp_zero(r);
- }
- s_mp_clamp(r);
- }
-
- CLEANUP:
- return res;
+ mp_err res = MP_OKAY;
+ int a_bits = mpl_significant_bits(a);
+ unsigned int i;
+
+ /* m1, m2 are statically-allocated mp_int of exactly the size we need */
+ mp_int m1;
+
+ mp_digit s1[ECP521_DIGITS] = { 0 };
+
+ MP_SIGN(&m1) = MP_ZPOS;
+ MP_ALLOC(&m1) = ECP521_DIGITS;
+ MP_USED(&m1) = ECP521_DIGITS;
+ MP_DIGITS(&m1) = s1;
+
+ if (a_bits < 521) {
+ if (a == r)
+ return MP_OKAY;
+ return mp_copy(a, r);
+ }
+ /* for polynomials larger than twice the field size or polynomials
+ * not using all words, use regular reduction */
+ if (a_bits > (521 * 2)) {
+ MP_CHECKOK(mp_mod(a, &meth->irr, r));
+ } else {
+#define FIRST_DIGIT (ECP521_DIGITS - 1)
+ for (i = FIRST_DIGIT; i < MP_USED(a) - 1; i++) {
+ s1[i - FIRST_DIGIT] = (MP_DIGIT(a, i) >> 9) | (MP_DIGIT(a, 1 + i) << (MP_DIGIT_BIT - 9));
+ }
+ s1[i - FIRST_DIGIT] = MP_DIGIT(a, i) >> 9;
+
+ if (a != r) {
+ MP_CHECKOK(s_mp_pad(r, ECP521_DIGITS));
+ for (i = 0; i < ECP521_DIGITS; i++) {
+ MP_DIGIT(r, i) = MP_DIGIT(a, i);
+ }
+ }
+ MP_USED(r) = ECP521_DIGITS;
+ MP_DIGIT(r, FIRST_DIGIT) &= 0x1FF;
+
+ MP_CHECKOK(s_mp_add(r, &m1));
+ if (MP_DIGIT(r, FIRST_DIGIT) & 0x200) {
+ MP_CHECKOK(s_mp_add_d(r, 1));
+ MP_DIGIT(r, FIRST_DIGIT) &= 0x1FF;
+ } else if (s_mp_cmp(r, &meth->irr) == 0) {
+ mp_zero(r);
+ }
+ s_mp_clamp(r);
+ }
+
+CLEANUP:
+ return res;
}
/* Compute the square of polynomial a, reduce modulo p521. Store the
- * result in r. r could be a. Uses optimized modular reduction for p521.
+ * result in r. r could be a. Uses optimized modular reduction for p521.
*/
static mp_err
ec_GFp_nistp521_sqr(const mp_int *a, mp_int *r, const GFMethod *meth)
{
- mp_err res = MP_OKAY;
+ mp_err res = MP_OKAY;
- MP_CHECKOK(mp_sqr(a, r));
- MP_CHECKOK(ec_GFp_nistp521_mod(r, r, meth));
- CLEANUP:
- return res;
+ MP_CHECKOK(mp_sqr(a, r));
+ MP_CHECKOK(ec_GFp_nistp521_mod(r, r, meth));
+CLEANUP:
+ return res;
}
/* Compute the product of two polynomials a and b, reduce modulo p521.
@@ -87,39 +87,39 @@ ec_GFp_nistp521_sqr(const mp_int *a, mp_int *r, const GFMethod *meth)
* optimized modular reduction for p521. */
static mp_err
ec_GFp_nistp521_mul(const mp_int *a, const mp_int *b, mp_int *r,
- const GFMethod *meth)
+ const GFMethod *meth)
{
- mp_err res = MP_OKAY;
+ mp_err res = MP_OKAY;
- MP_CHECKOK(mp_mul(a, b, r));
- MP_CHECKOK(ec_GFp_nistp521_mod(r, r, meth));
- CLEANUP:
- return res;
+ MP_CHECKOK(mp_mul(a, b, r));
+ MP_CHECKOK(ec_GFp_nistp521_mod(r, r, meth));
+CLEANUP:
+ return res;
}
/* Divides two field elements. If a is NULL, then returns the inverse of
* b. */
static mp_err
ec_GFp_nistp521_div(const mp_int *a, const mp_int *b, mp_int *r,
- const GFMethod *meth)
+ const GFMethod *meth)
{
- mp_err res = MP_OKAY;
- mp_int t;
-
- /* If a is NULL, then return the inverse of b, otherwise return a/b. */
- if (a == NULL) {
- return mp_invmod(b, &meth->irr, r);
- } else {
- /* MPI doesn't support divmod, so we implement it using invmod and
- * mulmod. */
- MP_CHECKOK(mp_init(&t));
- MP_CHECKOK(mp_invmod(b, &meth->irr, &t));
- MP_CHECKOK(mp_mul(a, &t, r));
- MP_CHECKOK(ec_GFp_nistp521_mod(r, r, meth));
- CLEANUP:
- mp_clear(&t);
- return res;
- }
+ mp_err res = MP_OKAY;
+ mp_int t;
+
+ /* If a is NULL, then return the inverse of b, otherwise return a/b. */
+ if (a == NULL) {
+ return mp_invmod(b, &meth->irr, r);
+ } else {
+ /* MPI doesn't support divmod, so we implement it using invmod and
+ * mulmod. */
+ MP_CHECKOK(mp_init(&t));
+ MP_CHECKOK(mp_invmod(b, &meth->irr, &t));
+ MP_CHECKOK(mp_mul(a, &t, r));
+ MP_CHECKOK(ec_GFp_nistp521_mod(r, r, meth));
+ CLEANUP:
+ mp_clear(&t);
+ return res;
+ }
}
/* Wire in fast field arithmetic and precomputation of base point for
@@ -127,11 +127,11 @@ ec_GFp_nistp521_div(const mp_int *a, const mp_int *b, mp_int *r,
mp_err
ec_group_set_gfp521(ECGroup *group, ECCurveName name)
{
- if (name == ECCurve_NIST_P521) {
- group->meth->field_mod = &ec_GFp_nistp521_mod;
- group->meth->field_mul = &ec_GFp_nistp521_mul;
- group->meth->field_sqr = &ec_GFp_nistp521_sqr;
- group->meth->field_div = &ec_GFp_nistp521_div;
- }
- return MP_OKAY;
+ if (name == ECCurve_NIST_P521) {
+ group->meth->field_mod = &ec_GFp_nistp521_mod;
+ group->meth->field_mul = &ec_GFp_nistp521_mul;
+ group->meth->field_sqr = &ec_GFp_nistp521_sqr;
+ group->meth->field_div = &ec_GFp_nistp521_div;
+ }
+ return MP_OKAY;
}