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Diffstat (limited to 'external_libs/python/pyzmq-14.7.0/bundled/libsodium/src/libsodium/crypto_scalarmult/curve25519/ref10/fe_tobytes_curve25519_ref10.c')
-rw-r--r--external_libs/python/pyzmq-14.7.0/bundled/libsodium/src/libsodium/crypto_scalarmult/curve25519/ref10/fe_tobytes_curve25519_ref10.c123
1 files changed, 0 insertions, 123 deletions
diff --git a/external_libs/python/pyzmq-14.7.0/bundled/libsodium/src/libsodium/crypto_scalarmult/curve25519/ref10/fe_tobytes_curve25519_ref10.c b/external_libs/python/pyzmq-14.7.0/bundled/libsodium/src/libsodium/crypto_scalarmult/curve25519/ref10/fe_tobytes_curve25519_ref10.c
deleted file mode 100644
index 4e033fb6..00000000
--- a/external_libs/python/pyzmq-14.7.0/bundled/libsodium/src/libsodium/crypto_scalarmult/curve25519/ref10/fe_tobytes_curve25519_ref10.c
+++ /dev/null
@@ -1,123 +0,0 @@
-#include "fe.h"
-
-#ifndef HAVE_TI_MODE
-
-/*
-Preconditions:
- |h| bounded by 1.1*2^25,1.1*2^24,1.1*2^25,1.1*2^24,etc.
-
-Write p=2^255-19; q=floor(h/p).
-Basic claim: q = floor(2^(-255)(h + 19 2^(-25)h9 + 2^(-1))).
-
-Proof:
- Have |h|<=p so |q|<=1 so |19^2 2^(-255) q|<1/4.
- Also have |h-2^230 h9|<2^230 so |19 2^(-255)(h-2^230 h9)|<1/4.
-
- Write y=2^(-1)-19^2 2^(-255)q-19 2^(-255)(h-2^230 h9).
- Then 0<y<1.
-
- Write r=h-pq.
- Have 0<=r<=p-1=2^255-20.
- Thus 0<=r+19(2^-255)r<r+19(2^-255)2^255<=2^255-1.
-
- Write x=r+19(2^-255)r+y.
- Then 0<x<2^255 so floor(2^(-255)x) = 0 so floor(q+2^(-255)x) = q.
-
- Have q+2^(-255)x = 2^(-255)(h + 19 2^(-25) h9 + 2^(-1))
- so floor(2^(-255)(h + 19 2^(-25) h9 + 2^(-1))) = q.
-*/
-
-void fe_tobytes(unsigned char *s,fe h)
-{
- crypto_int32 h0 = h[0];
- crypto_int32 h1 = h[1];
- crypto_int32 h2 = h[2];
- crypto_int32 h3 = h[3];
- crypto_int32 h4 = h[4];
- crypto_int32 h5 = h[5];
- crypto_int32 h6 = h[6];
- crypto_int32 h7 = h[7];
- crypto_int32 h8 = h[8];
- crypto_int32 h9 = h[9];
- crypto_int32 q;
- crypto_int32 carry0;
- crypto_int32 carry1;
- crypto_int32 carry2;
- crypto_int32 carry3;
- crypto_int32 carry4;
- crypto_int32 carry5;
- crypto_int32 carry6;
- crypto_int32 carry7;
- crypto_int32 carry8;
- crypto_int32 carry9;
-
- q = (19 * h9 + (((crypto_int32) 1) << 24)) >> 25;
- q = (h0 + q) >> 26;
- q = (h1 + q) >> 25;
- q = (h2 + q) >> 26;
- q = (h3 + q) >> 25;
- q = (h4 + q) >> 26;
- q = (h5 + q) >> 25;
- q = (h6 + q) >> 26;
- q = (h7 + q) >> 25;
- q = (h8 + q) >> 26;
- q = (h9 + q) >> 25;
-
- /* Goal: Output h-(2^255-19)q, which is between 0 and 2^255-20. */
- h0 += 19 * q;
- /* Goal: Output h-2^255 q, which is between 0 and 2^255-20. */
-
- carry0 = h0 >> 26; h1 += carry0; h0 -= carry0 << 26;
- carry1 = h1 >> 25; h2 += carry1; h1 -= carry1 << 25;
- carry2 = h2 >> 26; h3 += carry2; h2 -= carry2 << 26;
- carry3 = h3 >> 25; h4 += carry3; h3 -= carry3 << 25;
- carry4 = h4 >> 26; h5 += carry4; h4 -= carry4 << 26;
- carry5 = h5 >> 25; h6 += carry5; h5 -= carry5 << 25;
- carry6 = h6 >> 26; h7 += carry6; h6 -= carry6 << 26;
- carry7 = h7 >> 25; h8 += carry7; h7 -= carry7 << 25;
- carry8 = h8 >> 26; h9 += carry8; h8 -= carry8 << 26;
- carry9 = h9 >> 25; h9 -= carry9 << 25;
- /* h10 = carry9 */
-
- /*
- Goal: Output h0+...+2^255 h10-2^255 q, which is between 0 and 2^255-20.
- Have h0+...+2^230 h9 between 0 and 2^255-1;
- evidently 2^255 h10-2^255 q = 0.
- Goal: Output h0+...+2^230 h9.
- */
-
- s[0] = h0 >> 0;
- s[1] = h0 >> 8;
- s[2] = h0 >> 16;
- s[3] = (h0 >> 24) | (h1 << 2);
- s[4] = h1 >> 6;
- s[5] = h1 >> 14;
- s[6] = (h1 >> 22) | (h2 << 3);
- s[7] = h2 >> 5;
- s[8] = h2 >> 13;
- s[9] = (h2 >> 21) | (h3 << 5);
- s[10] = h3 >> 3;
- s[11] = h3 >> 11;
- s[12] = (h3 >> 19) | (h4 << 6);
- s[13] = h4 >> 2;
- s[14] = h4 >> 10;
- s[15] = h4 >> 18;
- s[16] = h5 >> 0;
- s[17] = h5 >> 8;
- s[18] = h5 >> 16;
- s[19] = (h5 >> 24) | (h6 << 1);
- s[20] = h6 >> 7;
- s[21] = h6 >> 15;
- s[22] = (h6 >> 23) | (h7 << 3);
- s[23] = h7 >> 5;
- s[24] = h7 >> 13;
- s[25] = (h7 >> 21) | (h8 << 4);
- s[26] = h8 >> 4;
- s[27] = h8 >> 12;
- s[28] = (h8 >> 20) | (h9 << 6);
- s[29] = h9 >> 2;
- s[30] = h9 >> 10;
- s[31] = h9 >> 18;
-}
-
-#endif