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Imported OpenSSL 1.1.1c

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This commit is contained in:
Steve Dower
2019-06-17 08:35:38 -07:00
parent cf34d7b72e
commit ea3c37b9ec
196 changed files with 38947 additions and 2649 deletions
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11
crypto/ec/ecp_nistp521.c
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@@ -357,10 +357,15 @@ static void felem_diff64(felem out, const felem in)
static void felem_diff_128_64(largefelem out, const felem in)
{
/*
* In order to prevent underflow, we add 0 mod p before subtracting.
* In order to prevent underflow, we add 64p mod p (which is equivalent
* to 0 mod p) before subtracting. p is 2^521 - 1, i.e. in binary a 521
* digit number with all bits set to 1. See "The representation of field
* elements" comment above for a description of how limbs are used to
* represent a number. 64p is represented with 8 limbs containing a number
* with 58 bits set and one limb with a number with 57 bits set.
*/
static const limb two63m6 = (((limb) 1) << 62) - (((limb) 1) << 5);
static const limb two63m5 = (((limb) 1) << 62) - (((limb) 1) << 4);
static const limb two63m6 = (((limb) 1) << 63) - (((limb) 1) << 6);
static const limb two63m5 = (((limb) 1) << 63) - (((limb) 1) << 5);
out[0] += two63m6 - in[0];
out[1] += two63m5 - in[1];