i2pd/core/crypto/ed25519/fe_sq.cpp

150 lines
5.8 KiB
C++

#include "fe.h"
#include "crypto_int64.h"
/*
h = f * f
Can overlap h with f.
Preconditions:
|f| bounded by 1.65*2^26,1.65*2^25,1.65*2^26,1.65*2^25,etc.
Postconditions:
|h| bounded by 1.01*2^25,1.01*2^24,1.01*2^25,1.01*2^24,etc.
*/
/*
See fe_mul.c for discussion of implementation strategy.
*/
void fe_sq(fe h,const fe f)
{
crypto_int32 f0 = f[0];
crypto_int32 f1 = f[1];
crypto_int32 f2 = f[2];
crypto_int32 f3 = f[3];
crypto_int32 f4 = f[4];
crypto_int32 f5 = f[5];
crypto_int32 f6 = f[6];
crypto_int32 f7 = f[7];
crypto_int32 f8 = f[8];
crypto_int32 f9 = f[9];
crypto_int32 f0_2 = 2 * f0;
crypto_int32 f1_2 = 2 * f1;
crypto_int32 f2_2 = 2 * f2;
crypto_int32 f3_2 = 2 * f3;
crypto_int32 f4_2 = 2 * f4;
crypto_int32 f5_2 = 2 * f5;
crypto_int32 f6_2 = 2 * f6;
crypto_int32 f7_2 = 2 * f7;
crypto_int32 f5_38 = 38 * f5; /* 1.959375*2^30 */
crypto_int32 f6_19 = 19 * f6; /* 1.959375*2^30 */
crypto_int32 f7_38 = 38 * f7; /* 1.959375*2^30 */
crypto_int32 f8_19 = 19 * f8; /* 1.959375*2^30 */
crypto_int32 f9_38 = 38 * f9; /* 1.959375*2^30 */
crypto_int64 f0f0 = f0 * (crypto_int64) f0;
crypto_int64 f0f1_2 = f0_2 * (crypto_int64) f1;
crypto_int64 f0f2_2 = f0_2 * (crypto_int64) f2;
crypto_int64 f0f3_2 = f0_2 * (crypto_int64) f3;
crypto_int64 f0f4_2 = f0_2 * (crypto_int64) f4;
crypto_int64 f0f5_2 = f0_2 * (crypto_int64) f5;
crypto_int64 f0f6_2 = f0_2 * (crypto_int64) f6;
crypto_int64 f0f7_2 = f0_2 * (crypto_int64) f7;
crypto_int64 f0f8_2 = f0_2 * (crypto_int64) f8;
crypto_int64 f0f9_2 = f0_2 * (crypto_int64) f9;
crypto_int64 f1f1_2 = f1_2 * (crypto_int64) f1;
crypto_int64 f1f2_2 = f1_2 * (crypto_int64) f2;
crypto_int64 f1f3_4 = f1_2 * (crypto_int64) f3_2;
crypto_int64 f1f4_2 = f1_2 * (crypto_int64) f4;
crypto_int64 f1f5_4 = f1_2 * (crypto_int64) f5_2;
crypto_int64 f1f6_2 = f1_2 * (crypto_int64) f6;
crypto_int64 f1f7_4 = f1_2 * (crypto_int64) f7_2;
crypto_int64 f1f8_2 = f1_2 * (crypto_int64) f8;
crypto_int64 f1f9_76 = f1_2 * (crypto_int64) f9_38;
crypto_int64 f2f2 = f2 * (crypto_int64) f2;
crypto_int64 f2f3_2 = f2_2 * (crypto_int64) f3;
crypto_int64 f2f4_2 = f2_2 * (crypto_int64) f4;
crypto_int64 f2f5_2 = f2_2 * (crypto_int64) f5;
crypto_int64 f2f6_2 = f2_2 * (crypto_int64) f6;
crypto_int64 f2f7_2 = f2_2 * (crypto_int64) f7;
crypto_int64 f2f8_38 = f2_2 * (crypto_int64) f8_19;
crypto_int64 f2f9_38 = f2 * (crypto_int64) f9_38;
crypto_int64 f3f3_2 = f3_2 * (crypto_int64) f3;
crypto_int64 f3f4_2 = f3_2 * (crypto_int64) f4;
crypto_int64 f3f5_4 = f3_2 * (crypto_int64) f5_2;
crypto_int64 f3f6_2 = f3_2 * (crypto_int64) f6;
crypto_int64 f3f7_76 = f3_2 * (crypto_int64) f7_38;
crypto_int64 f3f8_38 = f3_2 * (crypto_int64) f8_19;
crypto_int64 f3f9_76 = f3_2 * (crypto_int64) f9_38;
crypto_int64 f4f4 = f4 * (crypto_int64) f4;
crypto_int64 f4f5_2 = f4_2 * (crypto_int64) f5;
crypto_int64 f4f6_38 = f4_2 * (crypto_int64) f6_19;
crypto_int64 f4f7_38 = f4 * (crypto_int64) f7_38;
crypto_int64 f4f8_38 = f4_2 * (crypto_int64) f8_19;
crypto_int64 f4f9_38 = f4 * (crypto_int64) f9_38;
crypto_int64 f5f5_38 = f5 * (crypto_int64) f5_38;
crypto_int64 f5f6_38 = f5_2 * (crypto_int64) f6_19;
crypto_int64 f5f7_76 = f5_2 * (crypto_int64) f7_38;
crypto_int64 f5f8_38 = f5_2 * (crypto_int64) f8_19;
crypto_int64 f5f9_76 = f5_2 * (crypto_int64) f9_38;
crypto_int64 f6f6_19 = f6 * (crypto_int64) f6_19;
crypto_int64 f6f7_38 = f6 * (crypto_int64) f7_38;
crypto_int64 f6f8_38 = f6_2 * (crypto_int64) f8_19;
crypto_int64 f6f9_38 = f6 * (crypto_int64) f9_38;
crypto_int64 f7f7_38 = f7 * (crypto_int64) f7_38;
crypto_int64 f7f8_38 = f7_2 * (crypto_int64) f8_19;
crypto_int64 f7f9_76 = f7_2 * (crypto_int64) f9_38;
crypto_int64 f8f8_19 = f8 * (crypto_int64) f8_19;
crypto_int64 f8f9_38 = f8 * (crypto_int64) f9_38;
crypto_int64 f9f9_38 = f9 * (crypto_int64) f9_38;
crypto_int64 h0 = f0f0 +f1f9_76+f2f8_38+f3f7_76+f4f6_38+f5f5_38;
crypto_int64 h1 = f0f1_2+f2f9_38+f3f8_38+f4f7_38+f5f6_38;
crypto_int64 h2 = f0f2_2+f1f1_2 +f3f9_76+f4f8_38+f5f7_76+f6f6_19;
crypto_int64 h3 = f0f3_2+f1f2_2 +f4f9_38+f5f8_38+f6f7_38;
crypto_int64 h4 = f0f4_2+f1f3_4 +f2f2 +f5f9_76+f6f8_38+f7f7_38;
crypto_int64 h5 = f0f5_2+f1f4_2 +f2f3_2 +f6f9_38+f7f8_38;
crypto_int64 h6 = f0f6_2+f1f5_4 +f2f4_2 +f3f3_2 +f7f9_76+f8f8_19;
crypto_int64 h7 = f0f7_2+f1f6_2 +f2f5_2 +f3f4_2 +f8f9_38;
crypto_int64 h8 = f0f8_2+f1f7_4 +f2f6_2 +f3f5_4 +f4f4 +f9f9_38;
crypto_int64 h9 = f0f9_2+f1f8_2 +f2f7_2 +f3f6_2 +f4f5_2;
crypto_int64 carry0;
crypto_int64 carry1;
crypto_int64 carry2;
crypto_int64 carry3;
crypto_int64 carry4;
crypto_int64 carry5;
crypto_int64 carry6;
crypto_int64 carry7;
crypto_int64 carry8;
crypto_int64 carry9;
carry0 = (h0 + (crypto_int64) (1<<25)) >> 26; h1 += carry0; h0 -= carry0 << 26;
carry4 = (h4 + (crypto_int64) (1<<25)) >> 26; h5 += carry4; h4 -= carry4 << 26;
carry1 = (h1 + (crypto_int64) (1<<24)) >> 25; h2 += carry1; h1 -= carry1 << 25;
carry5 = (h5 + (crypto_int64) (1<<24)) >> 25; h6 += carry5; h5 -= carry5 << 25;
carry2 = (h2 + (crypto_int64) (1<<25)) >> 26; h3 += carry2; h2 -= carry2 << 26;
carry6 = (h6 + (crypto_int64) (1<<25)) >> 26; h7 += carry6; h6 -= carry6 << 26;
carry3 = (h3 + (crypto_int64) (1<<24)) >> 25; h4 += carry3; h3 -= carry3 << 25;
carry7 = (h7 + (crypto_int64) (1<<24)) >> 25; h8 += carry7; h7 -= carry7 << 25;
carry4 = (h4 + (crypto_int64) (1<<25)) >> 26; h5 += carry4; h4 -= carry4 << 26;
carry8 = (h8 + (crypto_int64) (1<<25)) >> 26; h9 += carry8; h8 -= carry8 << 26;
carry9 = (h9 + (crypto_int64) (1<<24)) >> 25; h0 += carry9 * 19; h9 -= carry9 << 25;
carry0 = (h0 + (crypto_int64) (1<<25)) >> 26; h1 += carry0; h0 -= carry0 << 26;
h[0] = h0;
h[1] = h1;
h[2] = h2;
h[3] = h3;
h[4] = h4;
h[5] = h5;
h[6] = h6;
h[7] = h7;
h[8] = h8;
h[9] = h9;
}