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pull/765/head
Jeffrey Walton 2018-12-13 18:51:15 -05:00
parent 27cd177209
commit 8c3432473b
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GPG Key ID: B36AB348921B1838
1 changed files with 4 additions and 29 deletions
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33
donna_32.cpp
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@ -2,10 +2,14 @@
// This is a integration of Andrew Moon's public domain code.
// Also see curve25519-donna-32bit.h.
// If needed, see Moon's commit "Go back to ignoring 256th bit",
// https://github.com/floodyberry/curve25519-donna/commit/57a683d18721a658
#include "pch.h"
#include "config.h"
#include "donna.h"
#include "secblock.h"
#include "stdcpp.h"
#include "misc.h"
#include "cpu.h"
@ -290,34 +294,6 @@ curve25519_expand(bignum25519 out, const byte in[32]) {
GetBlock<word32, LittleEndian> block(in);
block(x0)(x1)(x2)(x3)(x4)(x5)(x6)(x7);
#if 0
#if defined(CRYPTOPP_LITTLE_ENDIAN)
x0 = *(word32 *)(in + 0);
x1 = *(word32 *)(in + 4);
x2 = *(word32 *)(in + 8);
x3 = *(word32 *)(in + 12);
x4 = *(word32 *)(in + 16);
x5 = *(word32 *)(in + 20);
x6 = *(word32 *)(in + 24);
x7 = *(word32 *)(in + 28);
#else
#define F(s) \
((((word32)in[s + 0]) ) | \
(((word32)in[s + 1]) << 8) | \
(((word32)in[s + 2]) << 16) | \
(((word32)in[s + 3]) << 24))
x0 = F(0);
x1 = F(4);
x2 = F(8);
x3 = F(12);
x4 = F(16);
x5 = F(20);
x6 = F(24);
x7 = F(28);
#undef F
#endif
#endif
out[0] = ( x0 ) & reduce_mask_26;
out[1] = ((((word64)x1 << 32) | x0) >> 26) & reduce_mask_25;
out[2] = ((((word64)x2 << 32) | x1) >> 19) & reduce_mask_26;
@ -328,7 +304,6 @@ curve25519_expand(bignum25519 out, const byte in[32]) {
out[7] = ((((word64)x6 << 32) | x5) >> 19) & reduce_mask_25;
out[8] = ((((word64)x7 << 32) | x6) >> 12) & reduce_mask_26;
out[9] = (( x7) >> 6) & reduce_mask_25; /* ignore the top bit */
// out[9] = (( x7) >> 6) & reduce_mask_26;
}
/* Take a fully reduced polynomial form number and contract it into a little-endian, 32-byte array */