Reorder to improve inlining
This commit is contained in:
Frank Denis
parent
6872237df9
commit
f430f3a936
@ -257,6 +257,124 @@ void fe_frombytes(fe h,const unsigned char *s)
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h[9] = (crypto_int32) h9;
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}
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/*
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Preconditions:
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|h| bounded by 1.1*2^26,1.1*2^25,1.1*2^26,1.1*2^25,etc.
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Write p=2^255-19; q=floor(h/p).
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Basic claim: q = floor(2^(-255)(h + 19 2^(-25)h9 + 2^(-1))).
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Proof:
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Have |h|<=p so |q|<=1 so |19^2 2^(-255) q|<1/4.
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Also have |h-2^230 h9|<2^231 so |19 2^(-255)(h-2^230 h9)|<1/4.
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Write y=2^(-1)-19^2 2^(-255)q-19 2^(-255)(h-2^230 h9).
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Then 0<y<1.
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Write r=h-pq.
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Have 0<=r<=p-1=2^255-20.
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Thus 0<=r+19(2^-255)r<r+19(2^-255)2^255<=2^255-1.
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Write x=r+19(2^-255)r+y.
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Then 0<x<2^255 so floor(2^(-255)x) = 0 so floor(q+2^(-255)x) = q.
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Have q+2^(-255)x = 2^(-255)(h + 19 2^(-25) h9 + 2^(-1))
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so floor(2^(-255)(h + 19 2^(-25) h9 + 2^(-1))) = q.
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*/
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void fe_tobytes(unsigned char *s,const fe h)
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{
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crypto_int32 h0 = h[0];
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crypto_int32 h1 = h[1];
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crypto_int32 h2 = h[2];
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crypto_int32 h3 = h[3];
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crypto_int32 h4 = h[4];
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crypto_int32 h5 = h[5];
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crypto_int32 h6 = h[6];
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crypto_int32 h7 = h[7];
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crypto_int32 h8 = h[8];
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crypto_int32 h9 = h[9];
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crypto_int32 q;
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crypto_int32 carry0;
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crypto_int32 carry1;
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crypto_int32 carry2;
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crypto_int32 carry3;
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crypto_int32 carry4;
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crypto_int32 carry5;
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crypto_int32 carry6;
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crypto_int32 carry7;
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crypto_int32 carry8;
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crypto_int32 carry9;
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q = (19 * h9 + (((crypto_int32) 1) << 24)) >> 25;
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q = (h0 + q) >> 26;
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q = (h1 + q) >> 25;
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q = (h2 + q) >> 26;
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q = (h3 + q) >> 25;
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q = (h4 + q) >> 26;
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q = (h5 + q) >> 25;
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q = (h6 + q) >> 26;
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q = (h7 + q) >> 25;
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q = (h8 + q) >> 26;
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q = (h9 + q) >> 25;
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/* Goal: Output h-(2^255-19)q, which is between 0 and 2^255-20. */
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h0 += 19 * q;
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/* Goal: Output h-2^255 q, which is between 0 and 2^255-20. */
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carry0 = h0 >> 26; h1 += carry0; h0 -= carry0 << 26;
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carry1 = h1 >> 25; h2 += carry1; h1 -= carry1 << 25;
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carry2 = h2 >> 26; h3 += carry2; h2 -= carry2 << 26;
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carry3 = h3 >> 25; h4 += carry3; h3 -= carry3 << 25;
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carry4 = h4 >> 26; h5 += carry4; h4 -= carry4 << 26;
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carry5 = h5 >> 25; h6 += carry5; h5 -= carry5 << 25;
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carry6 = h6 >> 26; h7 += carry6; h6 -= carry6 << 26;
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carry7 = h7 >> 25; h8 += carry7; h7 -= carry7 << 25;
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carry8 = h8 >> 26; h9 += carry8; h8 -= carry8 << 26;
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carry9 = h9 >> 25; h9 -= carry9 << 25;
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/* h10 = carry9 */
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/*
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Goal: Output h0+...+2^255 h10-2^255 q, which is between 0 and 2^255-20.
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Have h0+...+2^230 h9 between 0 and 2^255-1;
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evidently 2^255 h10-2^255 q = 0.
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Goal: Output h0+...+2^230 h9.
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*/
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s[0] = h0 >> 0;
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s[1] = h0 >> 8;
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s[2] = h0 >> 16;
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s[3] = (h0 >> 24) | (h1 << 2);
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s[4] = h1 >> 6;
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s[5] = h1 >> 14;
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s[6] = (h1 >> 22) | (h2 << 3);
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s[7] = h2 >> 5;
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s[8] = h2 >> 13;
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s[9] = (h2 >> 21) | (h3 << 5);
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s[10] = h3 >> 3;
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s[11] = h3 >> 11;
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s[12] = (h3 >> 19) | (h4 << 6);
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s[13] = h4 >> 2;
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s[14] = h4 >> 10;
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s[15] = h4 >> 18;
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s[16] = h5 >> 0;
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s[17] = h5 >> 8;
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s[18] = h5 >> 16;
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s[19] = (h5 >> 24) | (h6 << 1);
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s[20] = h6 >> 7;
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s[21] = h6 >> 15;
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s[22] = (h6 >> 23) | (h7 << 3);
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s[23] = h7 >> 5;
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s[24] = h7 >> 13;
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s[25] = (h7 >> 21) | (h8 << 4);
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s[26] = h8 >> 4;
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s[27] = h8 >> 12;
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s[28] = (h8 >> 20) | (h9 << 6);
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s[29] = h9 >> 2;
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s[30] = h9 >> 10;
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s[31] = h9 >> 18;
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}
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/*
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return 1 if f is in {1,3,5,...,q-2}
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return 0 if f is in {0,2,4,...,q-1}
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@ -1074,124 +1192,6 @@ void fe_sub(fe h,const fe f,const fe g)
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h[9] = h9;
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}
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/*
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Preconditions:
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|h| bounded by 1.1*2^26,1.1*2^25,1.1*2^26,1.1*2^25,etc.
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Write p=2^255-19; q=floor(h/p).
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Basic claim: q = floor(2^(-255)(h + 19 2^(-25)h9 + 2^(-1))).
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Proof:
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Have |h|<=p so |q|<=1 so |19^2 2^(-255) q|<1/4.
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Also have |h-2^230 h9|<2^231 so |19 2^(-255)(h-2^230 h9)|<1/4.
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Write y=2^(-1)-19^2 2^(-255)q-19 2^(-255)(h-2^230 h9).
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Then 0<y<1.
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Write r=h-pq.
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Have 0<=r<=p-1=2^255-20.
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Thus 0<=r+19(2^-255)r<r+19(2^-255)2^255<=2^255-1.
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Write x=r+19(2^-255)r+y.
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Then 0<x<2^255 so floor(2^(-255)x) = 0 so floor(q+2^(-255)x) = q.
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Have q+2^(-255)x = 2^(-255)(h + 19 2^(-25) h9 + 2^(-1))
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so floor(2^(-255)(h + 19 2^(-25) h9 + 2^(-1))) = q.
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*/
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void fe_tobytes(unsigned char *s,const fe h)
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{
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crypto_int32 h0 = h[0];
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crypto_int32 h1 = h[1];
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crypto_int32 h2 = h[2];
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crypto_int32 h3 = h[3];
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crypto_int32 h4 = h[4];
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crypto_int32 h5 = h[5];
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crypto_int32 h6 = h[6];
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crypto_int32 h7 = h[7];
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crypto_int32 h8 = h[8];
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crypto_int32 h9 = h[9];
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crypto_int32 q;
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crypto_int32 carry0;
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crypto_int32 carry1;
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crypto_int32 carry2;
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crypto_int32 carry3;
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crypto_int32 carry4;
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crypto_int32 carry5;
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crypto_int32 carry6;
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crypto_int32 carry7;
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crypto_int32 carry8;
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crypto_int32 carry9;
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q = (19 * h9 + (((crypto_int32) 1) << 24)) >> 25;
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q = (h0 + q) >> 26;
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q = (h1 + q) >> 25;
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q = (h2 + q) >> 26;
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q = (h3 + q) >> 25;
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q = (h4 + q) >> 26;
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q = (h5 + q) >> 25;
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q = (h6 + q) >> 26;
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q = (h7 + q) >> 25;
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q = (h8 + q) >> 26;
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q = (h9 + q) >> 25;
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/* Goal: Output h-(2^255-19)q, which is between 0 and 2^255-20. */
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h0 += 19 * q;
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/* Goal: Output h-2^255 q, which is between 0 and 2^255-20. */
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carry0 = h0 >> 26; h1 += carry0; h0 -= carry0 << 26;
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carry1 = h1 >> 25; h2 += carry1; h1 -= carry1 << 25;
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carry2 = h2 >> 26; h3 += carry2; h2 -= carry2 << 26;
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carry3 = h3 >> 25; h4 += carry3; h3 -= carry3 << 25;
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carry4 = h4 >> 26; h5 += carry4; h4 -= carry4 << 26;
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carry5 = h5 >> 25; h6 += carry5; h5 -= carry5 << 25;
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carry6 = h6 >> 26; h7 += carry6; h6 -= carry6 << 26;
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carry7 = h7 >> 25; h8 += carry7; h7 -= carry7 << 25;
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carry8 = h8 >> 26; h9 += carry8; h8 -= carry8 << 26;
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carry9 = h9 >> 25; h9 -= carry9 << 25;
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/* h10 = carry9 */
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/*
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Goal: Output h0+...+2^255 h10-2^255 q, which is between 0 and 2^255-20.
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Have h0+...+2^230 h9 between 0 and 2^255-1;
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evidently 2^255 h10-2^255 q = 0.
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Goal: Output h0+...+2^230 h9.
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*/
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s[0] = h0 >> 0;
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s[1] = h0 >> 8;
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s[2] = h0 >> 16;
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s[3] = (h0 >> 24) | (h1 << 2);
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s[4] = h1 >> 6;
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s[5] = h1 >> 14;
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s[6] = (h1 >> 22) | (h2 << 3);
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s[7] = h2 >> 5;
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s[8] = h2 >> 13;
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s[9] = (h2 >> 21) | (h3 << 5);
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s[10] = h3 >> 3;
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s[11] = h3 >> 11;
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s[12] = (h3 >> 19) | (h4 << 6);
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s[13] = h4 >> 2;
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s[14] = h4 >> 10;
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s[15] = h4 >> 18;
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s[16] = h5 >> 0;
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s[17] = h5 >> 8;
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s[18] = h5 >> 16;
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s[19] = (h5 >> 24) | (h6 << 1);
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s[20] = h6 >> 7;
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s[21] = h6 >> 15;
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s[22] = (h6 >> 23) | (h7 << 3);
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s[23] = h7 >> 5;
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s[24] = h7 >> 13;
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s[25] = (h7 >> 21) | (h8 << 4);
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s[26] = h8 >> 4;
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s[27] = h8 >> 12;
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s[28] = (h8 >> 20) | (h9 << 6);
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s[29] = h9 >> 2;
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s[30] = h9 >> 10;
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s[31] = h9 >> 18;
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}
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/*
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r = p + q
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*/
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@ -1249,107 +1249,6 @@ static ge_precomp Bi[8] = {
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#include "base2.h"
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} ;
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/*
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r = a * A + b * B
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where a = a[0]+256*a[1]+...+256^31 a[31].
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and b = b[0]+256*b[1]+...+256^31 b[31].
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B is the Ed25519 base point (x,4/5) with x positive.
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*/
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void ge_double_scalarmult_vartime(ge_p2 *r,const unsigned char *a,const ge_p3 *A,const unsigned char *b)
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{
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signed char aslide[256];
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signed char bslide[256];
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ge_cached Ai[8]; /* A,3A,5A,7A,9A,11A,13A,15A */
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ge_p1p1 t;
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ge_p3 u;
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ge_p3 A2;
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int i;
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slide(aslide,a);
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slide(bslide,b);
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ge_p3_to_cached(&Ai[0],A);
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ge_p3_dbl(&t,A); ge_p1p1_to_p3(&A2,&t);
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ge_add(&t,&A2,&Ai[0]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[1],&u);
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ge_add(&t,&A2,&Ai[1]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[2],&u);
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ge_add(&t,&A2,&Ai[2]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[3],&u);
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ge_add(&t,&A2,&Ai[3]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[4],&u);
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ge_add(&t,&A2,&Ai[4]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[5],&u);
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ge_add(&t,&A2,&Ai[5]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[6],&u);
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ge_add(&t,&A2,&Ai[6]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[7],&u);
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ge_p2_0(r);
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for (i = 255;i >= 0;--i) {
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if (aslide[i] || bslide[i]) break;
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}
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for (;i >= 0;--i) {
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ge_p2_dbl(&t,r);
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if (aslide[i] > 0) {
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ge_p1p1_to_p3(&u,&t);
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ge_add(&t,&u,&Ai[aslide[i]/2]);
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} else if (aslide[i] < 0) {
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ge_p1p1_to_p3(&u,&t);
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ge_sub(&t,&u,&Ai[(-aslide[i])/2]);
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}
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if (bslide[i] > 0) {
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ge_p1p1_to_p3(&u,&t);
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ge_madd(&t,&u,&Bi[bslide[i]/2]);
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} else if (bslide[i] < 0) {
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ge_p1p1_to_p3(&u,&t);
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ge_msub(&t,&u,&Bi[(-bslide[i])/2]);
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}
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ge_p1p1_to_p2(r,&t);
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}
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}
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void ge_scalarmult_vartime(ge_p3 *r,const unsigned char *a,const ge_p3 *A)
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{
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signed char aslide[256];
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ge_cached Ai[8];
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ge_p1p1 t;
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ge_p3 u;
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ge_p3 A2;
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int i;
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slide(aslide,a);
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ge_p3_to_cached(&Ai[0],A);
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ge_p3_dbl(&t,A); ge_p1p1_to_p3(&A2,&t);
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ge_add(&t,&A2,&Ai[0]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[1],&u);
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ge_add(&t,&A2,&Ai[1]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[2],&u);
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ge_add(&t,&A2,&Ai[2]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[3],&u);
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ge_add(&t,&A2,&Ai[3]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[4],&u);
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ge_add(&t,&A2,&Ai[4]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[5],&u);
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ge_add(&t,&A2,&Ai[5]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[6],&u);
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ge_add(&t,&A2,&Ai[6]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[7],&u);
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ge_p3_0(r);
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for (i = 255;i >= 0;--i) {
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if (aslide[i]) break;
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}
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for (;i >= 0;--i) {
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ge_p3_dbl(&t,r);
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if (aslide[i] > 0) {
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ge_p1p1_to_p3(&u,&t);
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ge_add(&t,&u,&Ai[aslide[i]/2]);
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} else if (aslide[i] < 0) {
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ge_p1p1_to_p3(&u,&t);
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ge_sub(&t,&u,&Ai[(-aslide[i])/2]);
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}
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ge_p1p1_to_p3(r,&t);
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}
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}
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static const fe d = {
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-10913610,13857413,-15372611,6949391,114729,-8787816,-6275908,-3247719,-18696448,-12055116
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};
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@ -1496,17 +1395,6 @@ void ge_p3_0(ge_p3 *h)
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fe_0(h->T);
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}
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/*
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r = 2 * p
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*/
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void ge_p3_dbl(ge_p1p1 *r,const ge_p3 *p)
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{
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ge_p2 q;
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ge_p3_to_p2(&q,p);
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ge_p2_dbl(r,&q);
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}
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/*
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r = p
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*/
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@ -1547,6 +1435,17 @@ void ge_p3_tobytes(unsigned char *s,const ge_p3 *h)
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s[31] ^= fe_isnegative(x) << 7;
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}
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/*
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r = 2 * p
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*/
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void ge_p3_dbl(ge_p1p1 *r,const ge_p3 *p)
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{
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ge_p2 q;
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||||
ge_p3_to_p2(&q,p);
|
||||
ge_p2_dbl(r,&q);
|
||||
}
|
||||
|
||||
void ge_precomp_0(ge_precomp *h)
|
||||
{
|
||||
fe_1(h->yplusx);
|
||||
@ -1605,6 +1504,40 @@ static void ge_select(ge_precomp *t,int pos,signed char b)
|
||||
cmov(t,&minust,bnegative);
|
||||
}
|
||||
|
||||
/*
|
||||
r = p - q
|
||||
*/
|
||||
|
||||
void ge_sub(ge_p1p1 *r,const ge_p3 *p,const ge_cached *q)
|
||||
{
|
||||
fe t0;
|
||||
|
||||
fe_add(r->X, p->Y, p->X);
|
||||
fe_sub(r->Y, p->Y, p->X);
|
||||
fe_mul(r->Z, r->X, q->YminusX);
|
||||
fe_mul(r->Y, r->Y, q->YplusX);
|
||||
fe_mul(r->T, q->T2d, p->T);
|
||||
fe_mul(r->X, p->Z, q->Z);
|
||||
fe_add(t0, r->X, r->X);
|
||||
fe_sub(r->X, r->Z, r->Y);
|
||||
fe_add(r->Y, r->Z, r->Y);
|
||||
fe_sub(r->Z, t0, r->T);
|
||||
fe_add(r->T, t0, r->T);
|
||||
}
|
||||
|
||||
void ge_tobytes(unsigned char *s,const ge_p2 *h)
|
||||
{
|
||||
fe recip;
|
||||
fe x;
|
||||
fe y;
|
||||
|
||||
fe_invert(recip,h->Z);
|
||||
fe_mul(x,h->X,recip);
|
||||
fe_mul(y,h->Y,recip);
|
||||
fe_tobytes(s,y);
|
||||
s[31] ^= fe_isnegative(x) << 7;
|
||||
}
|
||||
|
||||
/*
|
||||
h = a * B
|
||||
where a = a[0]+256*a[1]+...+256^31 a[31]
|
||||
@ -1614,6 +1547,107 @@ Preconditions:
|
||||
a[31] <= 127
|
||||
*/
|
||||
|
||||
/*
|
||||
r = a * A + b * B
|
||||
where a = a[0]+256*a[1]+...+256^31 a[31].
|
||||
and b = b[0]+256*b[1]+...+256^31 b[31].
|
||||
B is the Ed25519 base point (x,4/5) with x positive.
|
||||
*/
|
||||
|
||||
void ge_double_scalarmult_vartime(ge_p2 *r,const unsigned char *a,const ge_p3 *A,const unsigned char *b)
|
||||
{
|
||||
signed char aslide[256];
|
||||
signed char bslide[256];
|
||||
ge_cached Ai[8]; /* A,3A,5A,7A,9A,11A,13A,15A */
|
||||
ge_p1p1 t;
|
||||
ge_p3 u;
|
||||
ge_p3 A2;
|
||||
int i;
|
||||
|
||||
slide(aslide,a);
|
||||
slide(bslide,b);
|
||||
|
||||
ge_p3_to_cached(&Ai[0],A);
|
||||
ge_p3_dbl(&t,A); ge_p1p1_to_p3(&A2,&t);
|
||||
ge_add(&t,&A2,&Ai[0]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[1],&u);
|
||||
ge_add(&t,&A2,&Ai[1]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[2],&u);
|
||||
ge_add(&t,&A2,&Ai[2]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[3],&u);
|
||||
ge_add(&t,&A2,&Ai[3]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[4],&u);
|
||||
ge_add(&t,&A2,&Ai[4]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[5],&u);
|
||||
ge_add(&t,&A2,&Ai[5]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[6],&u);
|
||||
ge_add(&t,&A2,&Ai[6]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[7],&u);
|
||||
|
||||
ge_p2_0(r);
|
||||
|
||||
for (i = 255;i >= 0;--i) {
|
||||
if (aslide[i] || bslide[i]) break;
|
||||
}
|
||||
|
||||
for (;i >= 0;--i) {
|
||||
ge_p2_dbl(&t,r);
|
||||
|
||||
if (aslide[i] > 0) {
|
||||
ge_p1p1_to_p3(&u,&t);
|
||||
ge_add(&t,&u,&Ai[aslide[i]/2]);
|
||||
} else if (aslide[i] < 0) {
|
||||
ge_p1p1_to_p3(&u,&t);
|
||||
ge_sub(&t,&u,&Ai[(-aslide[i])/2]);
|
||||
}
|
||||
|
||||
if (bslide[i] > 0) {
|
||||
ge_p1p1_to_p3(&u,&t);
|
||||
ge_madd(&t,&u,&Bi[bslide[i]/2]);
|
||||
} else if (bslide[i] < 0) {
|
||||
ge_p1p1_to_p3(&u,&t);
|
||||
ge_msub(&t,&u,&Bi[(-bslide[i])/2]);
|
||||
}
|
||||
|
||||
ge_p1p1_to_p2(r,&t);
|
||||
}
|
||||
}
|
||||
|
||||
void ge_scalarmult_vartime(ge_p3 *r,const unsigned char *a,const ge_p3 *A)
|
||||
{
|
||||
signed char aslide[256];
|
||||
ge_cached Ai[8];
|
||||
ge_p1p1 t;
|
||||
ge_p3 u;
|
||||
ge_p3 A2;
|
||||
int i;
|
||||
|
||||
slide(aslide,a);
|
||||
|
||||
ge_p3_to_cached(&Ai[0],A);
|
||||
ge_p3_dbl(&t,A); ge_p1p1_to_p3(&A2,&t);
|
||||
ge_add(&t,&A2,&Ai[0]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[1],&u);
|
||||
ge_add(&t,&A2,&Ai[1]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[2],&u);
|
||||
ge_add(&t,&A2,&Ai[2]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[3],&u);
|
||||
ge_add(&t,&A2,&Ai[3]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[4],&u);
|
||||
ge_add(&t,&A2,&Ai[4]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[5],&u);
|
||||
ge_add(&t,&A2,&Ai[5]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[6],&u);
|
||||
ge_add(&t,&A2,&Ai[6]); ge_p1p1_to_p3(&u,&t); ge_p3_to_cached(&Ai[7],&u);
|
||||
|
||||
ge_p3_0(r);
|
||||
|
||||
for (i = 255;i >= 0;--i) {
|
||||
if (aslide[i]) break;
|
||||
}
|
||||
|
||||
for (;i >= 0;--i) {
|
||||
ge_p3_dbl(&t,r);
|
||||
|
||||
if (aslide[i] > 0) {
|
||||
ge_p1p1_to_p3(&u,&t);
|
||||
ge_add(&t,&u,&Ai[aslide[i]/2]);
|
||||
} else if (aslide[i] < 0) {
|
||||
ge_p1p1_to_p3(&u,&t);
|
||||
ge_sub(&t,&u,&Ai[(-aslide[i])/2]);
|
||||
}
|
||||
|
||||
ge_p1p1_to_p3(r,&t);
|
||||
}
|
||||
}
|
||||
|
||||
void ge_scalarmult_base(ge_p3 *h,const unsigned char *a)
|
||||
{
|
||||
signed char e[64];
|
||||
@ -1657,40 +1691,6 @@ void ge_scalarmult_base(ge_p3 *h,const unsigned char *a)
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
r = p - q
|
||||
*/
|
||||
|
||||
void ge_sub(ge_p1p1 *r,const ge_p3 *p,const ge_cached *q)
|
||||
{
|
||||
fe t0;
|
||||
|
||||
fe_add(r->X, p->Y, p->X);
|
||||
fe_sub(r->Y, p->Y, p->X);
|
||||
fe_mul(r->Z, r->X, q->YminusX);
|
||||
fe_mul(r->Y, r->Y, q->YplusX);
|
||||
fe_mul(r->T, q->T2d, p->T);
|
||||
fe_mul(r->X, p->Z, q->Z);
|
||||
fe_add(t0, r->X, r->X);
|
||||
fe_sub(r->X, r->Z, r->Y);
|
||||
fe_add(r->Y, r->Z, r->Y);
|
||||
fe_sub(r->Z, t0, r->T);
|
||||
fe_add(r->T, t0, r->T);
|
||||
}
|
||||
|
||||
void ge_tobytes(unsigned char *s,const ge_p2 *h)
|
||||
{
|
||||
fe recip;
|
||||
fe x;
|
||||
fe y;
|
||||
|
||||
fe_invert(recip,h->Z);
|
||||
fe_mul(x,h->X,recip);
|
||||
fe_mul(y,h->Y,recip);
|
||||
fe_tobytes(s,y);
|
||||
s[31] ^= fe_isnegative(x) << 7;
|
||||
}
|
||||
|
||||
/*
|
||||
Input:
|
||||
a[0]+256*a[1]+...+256^31*a[31] = a
|
||||
|
||||
Loading…
Reference in New Issue
Block a user