mirror of
https://source.quilibrium.com/quilibrium/ceremonyclient.git
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797 lines
17 KiB
Go
797 lines
17 KiB
Go
/*
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* Copyright (c) 2012-2020 MIRACL UK Ltd.
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*
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* This file is part of MIRACL Core
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* (see https://github.com/miracl/core).
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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/* Kyber API */
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package core
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//import "fmt"
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const KY_LGN uint = 8
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const KY_DEGREE int = (1 << KY_LGN);
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const KY_PRIME int32 = 0xD01
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const KY_ONE int32 = 0x549 // R mod Q
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const KY_QINV int32 = 62209 // q^(-1) mod 2^16
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const KYBER_SECRET_CPA_SIZE_512 int = (2*(KY_DEGREE*3)/2)
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const KYBER_PUBLIC_SIZE_512 int = (32+2*(KY_DEGREE*3)/2)
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const KYBER_CIPHERTEXT_SIZE_512 int = ((10*2+4)*KY_DEGREE/8)
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const KYBER_SECRET_CCA_SIZE_512 int = (KYBER_SECRET_CPA_SIZE_512+KYBER_PUBLIC_SIZE_512+64)
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const KYBER_SHARED_SECRET_512 int = 32
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const KYBER_SECRET_CPA_SIZE_768 int = (3*(KY_DEGREE*3)/2)
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const KYBER_PUBLIC_SIZE_768 int = (32+3*(KY_DEGREE*3)/2)
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const KYBER_CIPHERTEXT_SIZE_768 int = ((10*3+4)*KY_DEGREE/8)
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const KYBER_SECRET_CCA_SIZE_768 int = (KYBER_SECRET_CPA_SIZE_768+KYBER_PUBLIC_SIZE_768+64)
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const KYBER_SHARED_SECRET_768 int = 32
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const KYBER_SECRET_CPA_SIZE_1024 int = (4*(KY_DEGREE*3)/2)
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const KYBER_PUBLIC_SIZE_1024 int = (32+4*(KY_DEGREE*3)/2)
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const KYBER_CIPHERTEXT_SIZE_1024 int = ((11*4+5)*KY_DEGREE/8)
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const KYBER_SECRET_CCA_SIZE_1024 int = (KYBER_SECRET_CPA_SIZE_1024+KYBER_PUBLIC_SIZE_1024+64)
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const KYBER_SHARED_SECRET_1024 int = 32
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const KY_MAXK = 4;
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// parameters for each security level
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// K,eta1,eta2,du,dv,shared secret
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var PARAMS_512 = [6]int{2,3,2,10,4,32}
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var PARAMS_768 = [6]int{3,2,2,10,4,32}
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var PARAMS_1024 = [6]int{4,2,2,11,5,32}
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/* Translated from public domain reference implementation code - taken from https://github.com/pq-crystals/kyber */
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var ZETAS = [256]int16{
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-1044, -758, -359, -1517, 1493, 1422, 287, 202,
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-171, 622, 1577, 182, 962, -1202, -1474, 1468,
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573, -1325, 264, 383, -829, 1458, -1602, -130,
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-681, 1017, 732, 608, -1542, 411, -205, -1571,
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1223, 652, -552, 1015, -1293, 1491, -282, -1544,
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516, -8, -320, -666, -1618, -1162, 126, 1469,
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-853, -90, -271, 830, 107, -1421, -247, -951,
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-398, 961, -1508, -725, 448, -1065, 677, -1275,
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-1103, 430, 555, 843, -1251, 871, 1550, 105,
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422, 587, 177, -235, -291, -460, 1574, 1653,
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-246, 778, 1159, -147, -777, 1483, -602, 1119,
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-1590, 644, -872, 349, 418, 329, -156, -75,
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817, 1097, 603, 610, 1322, -1285, -1465, 384,
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-1215, -136, 1218, -1335, -874, 220, -1187, -1659,
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-1185, -1530, -1278, 794, -1510, -854, -870, 478,
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-108, -308, 996, 991, 958, -1460, 1522, 1628}
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func montgomery_reduce(a int32) int16 {
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t := int16(a*KY_QINV)
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t = int16((a - int32(t)*KY_PRIME) >> 16)
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return t
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}
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func barrett_reduce(a int16) int16 {
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v := int16(((int32(1)<<26) + KY_PRIME/2)/KY_PRIME)
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vv := int32(v)
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aa := int32(a)
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t := int16((vv*aa + 0x2000000) >> 26);
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t *= int16(KY_PRIME)
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return int16(a - t);
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}
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func fqmul(a int16, b int16) int16 {
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return montgomery_reduce(int32(a)*int32(b));
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}
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func ntt(r []int16) {
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var j int
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k := 1
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for len := 128; len >= 2; len >>= 1 {
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for start := 0; start < 256; start = j + len {
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zeta := ZETAS[k]; k+=1
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for j = start; j < start + len; j++ {
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t := fqmul(zeta, r[j + len])
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r[j + len] = r[j] - t
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r[j] = r[j] + t
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}
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}
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}
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}
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func invntt(r []int16) {
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var j int
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f := int16(1441) // mont^2/128
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k := 127
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for len := 2; len <= 128; len <<= 1 {
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for start := 0; start < 256; start = j + len {
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zeta := ZETAS[k]; k-=1
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for j = start; j < start + len; j++ {
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t := r[j]
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r[j] = barrett_reduce(t + r[j + len])
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r[j + len] = (r[j + len] - t)
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r[j + len] = fqmul(zeta, r[j + len])
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}
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}
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}
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for j := 0; j < 256; j++ {
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r[j] = fqmul(r[j], f)
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}
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}
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func basemul(index int,r []int16, a []int16, b []int16,zeta int16) {
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i:=index
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j:=index+1
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r[i] = fqmul(a[j], b[j])
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r[i] = fqmul(r[i], zeta)
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r[i] += fqmul(a[i], b[i])
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r[j] = fqmul(a[i], b[j])
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r[j] += fqmul(a[j], b[i])
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}
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func poly_reduce(r []int16) {
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for i:=0;i<KY_DEGREE;i++ {
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r[i] = barrett_reduce(r[i])
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}
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}
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func poly_ntt(r []int16) {
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ntt(r)
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poly_reduce(r)
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}
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func poly_invntt(r []int16) {
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invntt(r)
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}
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// Note r must be distinct from a and b
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func poly_mul(r []int16, a []int16, b []int16) {
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for i := 0; i < KY_DEGREE/4; i++ {
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basemul(4*i,r,a,b,ZETAS[64+i])
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basemul(4*i+2,r,a,b,-ZETAS[64+i])
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}
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}
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func poly_tomont(r []int16) {
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f := int32(KY_ONE);
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for i:=0;i<KY_DEGREE;i++ {
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r[i] = montgomery_reduce(int32(r[i])*f)
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}
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}
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/* End of public domain reference code use */
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// copy polynomial
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func poly_copy(p1 []int16, p2 []int16) {
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for i := 0; i < KY_DEGREE; i++ {
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p1[i] = p2[i]
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}
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}
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// zero polynomial
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func poly_zero(p1 []int16) {
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for i := 0; i < KY_DEGREE; i++ {
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p1[i] = 0
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}
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}
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// add polynomials
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func poly_add(p1 []int16, p2 []int16, p3 []int16) {
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for i := 0; i < KY_DEGREE; i++ {
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p1[i] = (p2[i] + p3[i])
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}
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}
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// subtract polynomials
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func poly_sub(p1 []int16, p2 []int16, p3 []int16) {
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for i := 0; i < KY_DEGREE; i++ {
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p1[i] = (p2[i] - p3[i])
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}
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}
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// Generate A[i][j] from rho
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func expandAij(rho []byte,Aij []int16,i int,j int) {
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sh := NewSHA3(SHA3_SHAKE128)
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var buff [640]byte // should be plenty (?)
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for m:=0;m<32;m++ {
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sh.Process(rho[m])
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}
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sh.Process(byte(j&0xff))
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sh.Process(byte(i&0xff))
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sh.Shake(buff[:],640)
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i = 0
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j = 0
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for j<KY_DEGREE {
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d1 := int16(buff[i])+256*int16(buff[i+1]&0x0F);
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d2 := int16(buff[i+1])/16+16*int16(buff[i+2]);
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if (d1<int16(KY_PRIME)) {
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Aij[j]=d1; j+=1
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}
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if (d2<int16(KY_PRIME) && j<KY_DEGREE) {
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Aij[j]=d2; j+=1
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}
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i+=3
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}
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}
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// get n-th bit from byte array
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func getbit(b []byte,n int) int {
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wd:=n/8;
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bt:=n%8;
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return int((b[wd]>>bt)&1)
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}
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// centered binomial distribution
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func cbd(bts []byte,eta int,f []int16) {
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for i:=0;i<KY_DEGREE;i++ {
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a:=0; b:=0
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for j:=0;j<eta;j++ {
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a+=getbit(bts,2*i*eta+j)
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b+=getbit(bts,2*i*eta+eta+j)
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}
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f[i]=int16(a-b)
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}
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}
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// extract ab bits into word from dense byte stream
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func nextword(ab int,t []byte,position []int) int16 {
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ptr:=position[0] // index in array
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bts:=position[1] // bit index in byte
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r:=int16(t[ptr]>>bts)
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mask:=int16((1<<ab)-1)
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i:=0
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gotbits:=8-bts // bits left in current byte
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for gotbits<ab {
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i++
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w:=int16(t[ptr+i])
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r|=w<<gotbits
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gotbits+=8
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}
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bts+=ab
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for bts>=8{
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bts-=8
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ptr++
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}
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w:=int16(r&mask)
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position[0]=ptr
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position[1]=bts
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return w
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}
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// array t has ab active bits per word
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// extract bytes from array of words
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// if max!=0 then -max<=t[i]<=+max
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func nextbyte16(ab int,t []int16,position []int) byte {
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ptr:=position[0] // index in array
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bts:=position[1] // bit index in byte
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left:=ab-bts // number of bits left in this word
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i:=0
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k:=ptr%256
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w:=t[k]; w+=(w>>15)&int16(KY_PRIME)
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r:=int16(w>>bts);
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for left<8 {
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i++
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w=t[k+i]; w+=(w>>15)&int16(KY_PRIME)
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r|=w<<left
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left+=ab
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}
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bts+=8
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for bts>=ab {
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bts-=ab;
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ptr++;
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}
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position[0]=ptr
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position[1]=bts
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return byte(r&0xff);
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}
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// encode polynomial vector of length len with coefficients of length L, into packed bytes
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func encode(t []int16,pos []int,L int,pack []byte,pptr int) {
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k:=(KY_DEGREE*L)/8 // compressed length
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for n:=0;n<k;n++ {
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pack[n+pptr*k]=nextbyte16(L,t,pos)
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}
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}
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func chk_encode(t []int16,pos []int,L int,pack []byte,pptr int) byte {
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k:=(KY_DEGREE*L)/8
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diff:=byte(0)
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for n:=0;n<k;n++ {
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m:=nextbyte16(L,t,pos)
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diff|=(m^pack[n+pptr*k])
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}
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return diff;
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}
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// decode packed bytes into polynomial vector, with coefficients of length L
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// pos indicates current position in byte array pack
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func decode(pack []byte,L int,t []int16,pos []int) {
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for i:=0;i<KY_DEGREE;i++ {
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t[i]=nextword(L,pack,pos)
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}
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}
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// compress polynomial coefficents in place, for polynomial vector of length len
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func compress(t []int16,d int) {
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twod:=int32(1<<d)
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for i:=0;i<KY_DEGREE;i++ {
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t[i]+=(t[i]>>15)&int16(KY_PRIME)
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t[i]= int16(((twod*int32(t[i])+KY_PRIME/2)/KY_PRIME)&(twod-1))
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}
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}
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// decompress polynomial coefficents in place, for polynomial vector of length len
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func decompress(t []int16,d int) {
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twod1:=int32(1<<(d-1))
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for i:=0;i<KY_DEGREE;i++ {
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t[i]=int16((KY_PRIME*int32(t[i])+twod1)>>d)
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}
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}
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// input entropy, output key pair
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func cpa_keypair(params [6]int,tau []byte,sk []byte,pk []byte) {
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sh := NewSHA3(SHA3_HASH512)
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var rho [32]byte
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var sigma [33]byte
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var buff [256]byte
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ck:=params[0]
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var r [KY_DEGREE]int16
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var w [KY_DEGREE]int16
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var Aij [KY_DEGREE]int16
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var s= make([][KY_DEGREE]int16, ck)
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var e= make([][KY_DEGREE]int16, ck)
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var p= make([][KY_DEGREE]int16, ck)
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eta1:=params[1]
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public_key_size:=32+ck*(KY_DEGREE*3)/2
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// secret_cpa_key_size:=ck*(KY_DEGREE*3)/2
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for i:=0;i<32;i++ {
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sh.Process(tau[i])
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}
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bf := sh.Hash();
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for i:=0;i<32;i++ {
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rho[i]=bf[i]
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sigma[i]=bf[i+32]
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}
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sigma[32]=0 // N
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// create s
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for i:=0;i<ck;i++ {
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sh= NewSHA3(SHA3_SHAKE256)
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for j:=0;j<33;j++{
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sh.Process(sigma[j])
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}
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sh.Shake(buff[:],64*eta1);
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cbd(buff[:],eta1,s[i][:])
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sigma[32]+=1
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}
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// create e
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for i:=0;i<ck;i++ {
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sh= NewSHA3(SHA3_SHAKE256)
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for j:=0;j<33;j++ {
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sh.Process(sigma[j])
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}
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sh.Shake(buff[:],64*eta1)
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cbd(buff[:],eta1,e[i][:])
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sigma[32]+=1
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}
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for k:=0;k<ck;k++ {
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poly_ntt(s[k][:])
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poly_ntt(e[k][:])
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}
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for i:=0;i<ck;i++ {
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expandAij(rho[:],Aij[:],i,0)
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poly_mul(r[:],Aij[:],s[0][:])
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for j:=1;j<ck;j++ {
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expandAij(rho[:],Aij[:],i,j)
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poly_mul(w[:],s[j][:],Aij[:])
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poly_add(r[:],r[:],w[:])
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}
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poly_reduce(r[:])
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poly_tomont(r[:])
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poly_add(p[i][:],r[:],e[i][:])
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poly_reduce(p[i][:])
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}
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var pos [2]int
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pos[0]=0; pos[1]=0
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for i:=0;i<ck;i++ {
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encode(s[i][:],pos[:],12,sk,i)
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}
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pos[0]=0; pos[1]=0
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for i:=0;i<ck;i++ {
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encode(p[i][:],pos[:],12,pk,i)
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}
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for i:=0;i<32;i++ {
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pk[public_key_size-32+i]=rho[i]
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}
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}
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// input 64 random bytes, output secret and public keys
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func cca_keypair(params [6]int,randbytes64 []byte,sk []byte,pk []byte) {
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sh:= NewSHA3(SHA3_HASH256)
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sks:=(params[0]*(KY_DEGREE*3)/2)
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pks:=(32+params[0]*(KY_DEGREE*3)/2)
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cpa_keypair(params,randbytes64[0:32],sk,pk)
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for i:=0;i<pks;i++ {
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sk[sks+i]=pk[i]
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}
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for i:=0;i<pks;i++ {
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sh.Process(pk[i])
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}
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h:=sh.Hash();
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for i:=0;i<32;i++ {
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sk[sks+pks+i]=h[i]
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}
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for i:=0;i<32;i++ {
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sk[sks+pks+32+i]=randbytes64[32+i]
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}
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}
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func cpa_base_encrypt(params [6]int,coins []byte,pk []byte,ss []byte,u [][256]int16, v []int16) {
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var rho [32]byte
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var sigma [33]byte
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var buff [256]byte
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ck:=params[0]
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var r [KY_DEGREE]int16
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var w [KY_DEGREE]int16
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var Aij [KY_DEGREE]int16
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var q= make([][KY_DEGREE]int16, ck)
|
|
var p= make([][KY_DEGREE]int16, ck)
|
|
|
|
eta1:=params[1]
|
|
eta2:=params[2]
|
|
du:=params[3]
|
|
dv:=params[4]
|
|
public_key_size:=32+ck*(KY_DEGREE*3)/2
|
|
|
|
for i:=0;i<32;i++ {
|
|
sigma[i]=coins[i] //i+6 //RAND_byte(RNG);
|
|
}
|
|
sigma[32]=0
|
|
|
|
for i:=0;i<32;i++ {
|
|
rho[i]=pk[public_key_size-32+i]
|
|
}
|
|
|
|
// create q
|
|
for i:=0;i<ck;i++ {
|
|
sh := NewSHA3(SHA3_SHAKE256)
|
|
for j:=0;j<33;j++ {
|
|
sh.Process(sigma[j])
|
|
}
|
|
sh.Shake(buff[:],64*eta1)
|
|
cbd(buff[:],eta1,q[i][:])
|
|
sigma[32]+=1
|
|
}
|
|
// create e1
|
|
for i:=0;i<ck;i++ {
|
|
sh := NewSHA3(SHA3_SHAKE256)
|
|
for j:=0;j<33;j++ {
|
|
sh.Process(sigma[j])
|
|
}
|
|
sh.Shake(buff[:],64*eta2);
|
|
cbd(buff[:],eta1,u[i][:]) // e1
|
|
sigma[32]+=1
|
|
}
|
|
for i:=0;i<ck;i++ {
|
|
poly_ntt(q[i][:])
|
|
}
|
|
|
|
for i:=0;i<ck;i++ {
|
|
expandAij(rho[:],Aij[:],0,i)
|
|
poly_mul(r[:],Aij[:],q[0][:])
|
|
for j:=1;j<ck;j++ {
|
|
expandAij(rho[:],Aij[:],j,i)
|
|
poly_mul(w[:],q[j][:],Aij[:])
|
|
poly_add(r[:],r[:],w[:])
|
|
}
|
|
poly_reduce(r[:]);
|
|
poly_invntt(r[:]);
|
|
poly_add(u[i][:],u[i][:],r[:]);
|
|
poly_reduce(u[i][:]);
|
|
}
|
|
|
|
var pos [2]int
|
|
pos[0]=0; pos[1]=0
|
|
for i:=0;i<ck;i++ {
|
|
decode(pk,12,p[i][:],pos[:])
|
|
}
|
|
|
|
poly_mul(v[:],p[0][:],q[0][:])
|
|
|
|
for i:=1;i<ck;i++ {
|
|
poly_mul(r[:],p[i][:],q[i][:])
|
|
poly_add(v[:],v[:],r[:])
|
|
}
|
|
poly_invntt(v[:])
|
|
|
|
// create e2
|
|
sh := NewSHA3(SHA3_SHAKE256)
|
|
for j:=0;j<33;j++ {
|
|
sh.Process(sigma[j])
|
|
}
|
|
sh.Shake(buff[:],64*eta2)
|
|
cbd(buff[:],eta1,w[:]) // e2
|
|
|
|
poly_add(v[:],v[:],w[:])
|
|
pos[0]=0; pos[1]=0
|
|
decode(ss,1,r[:],pos[:])
|
|
decompress(r[:],1)
|
|
|
|
poly_add(v[:],v[:],r[:])
|
|
poly_reduce(v[:])
|
|
|
|
for i:=0;i<ck;i++ {
|
|
compress(u[i][:],du)
|
|
}
|
|
compress(v[:],dv)
|
|
}
|
|
|
|
// Given input of entropy, public key and shared secret is an input, outputs ciphertext
|
|
func cpa_encrypt(params [6]int,coins []byte,pk []byte,ss []byte,ct []byte) {
|
|
ck:=params[0]
|
|
var v [KY_DEGREE]int16
|
|
var u= make([][KY_DEGREE]int16, ck)
|
|
|
|
du:=params[3]
|
|
dv:=params[4]
|
|
ciphertext_size:=(du*ck+dv)*KY_DEGREE/8
|
|
|
|
cpa_base_encrypt(params,coins,pk,ss,u,v[:])
|
|
var pos [2]int
|
|
pos[0]=0; pos[1]=0
|
|
for i:=0;i<ck;i++ {
|
|
encode(u[i][:],pos[:],du,ct,i)
|
|
}
|
|
encode(v[:],pos[:],dv,ct[ciphertext_size-(dv*KY_DEGREE/8):ciphertext_size],0)
|
|
}
|
|
|
|
// Re-encrypt and check that ct is OK (if so return is zero)
|
|
func cpa_check_encrypt(params [6]int,coins []byte,pk []byte,ss []byte,ct []byte) byte {
|
|
ck:=params[0]
|
|
var v [KY_DEGREE]int16
|
|
var u= make([][KY_DEGREE]int16, ck)
|
|
|
|
du:=params[3]
|
|
dv:=params[4]
|
|
ciphertext_size:=(du*ck+dv)*KY_DEGREE/8
|
|
|
|
d1:=byte(0)
|
|
|
|
cpa_base_encrypt(params,coins,pk,ss,u,v[:]);
|
|
var pos [2]int
|
|
pos[0]=0; pos[1]=0
|
|
|
|
for i:=0;i<ck;i++ {
|
|
d1|=chk_encode(u[i][:],pos[:],du,ct,i)
|
|
}
|
|
|
|
d2:=chk_encode(v[:],pos[:],dv,ct[ciphertext_size-(dv*KY_DEGREE/8):ciphertext_size],0);
|
|
if (d1|d2)==0 {
|
|
return 0
|
|
} else {
|
|
return byte(0xff)
|
|
}
|
|
}
|
|
|
|
func cca_encrypt(params [6]int,randbytes32 []byte,pk []byte,ss []byte,ct []byte) {
|
|
var coins [32]byte
|
|
|
|
ck:=params[0]
|
|
du:=params[3]
|
|
dv:=params[4]
|
|
shared_secret_size:=params[5]
|
|
public_key_size:=32+ck*(KY_DEGREE*3)/2
|
|
ciphertext_size:=(du*ck+dv)*KY_DEGREE/8
|
|
|
|
sh := NewSHA3(SHA3_HASH256)
|
|
for i:=0;i<32;i++{
|
|
sh.Process(randbytes32[i])
|
|
}
|
|
hm := sh.Hash();
|
|
|
|
sh = NewSHA3(SHA3_HASH256)
|
|
for i:=0;i<public_key_size;i++ {
|
|
sh.Process(pk[i])
|
|
}
|
|
h := sh.Hash()
|
|
|
|
sh = NewSHA3(SHA3_HASH512);
|
|
for i:=0;i<32;i++ {
|
|
sh.Process(hm[i])
|
|
}
|
|
for i:=0;i<32;i++ {
|
|
sh.Process(h[i])
|
|
}
|
|
g:= sh.Hash()
|
|
|
|
for i:=0;i<32;i++ {
|
|
coins[i]=g[i+32]
|
|
}
|
|
|
|
cpa_encrypt(params,coins[:],pk,hm,ct)
|
|
|
|
sh = NewSHA3(SHA3_HASH256)
|
|
for i:=0;i<ciphertext_size;i++ {
|
|
sh.Process(ct[i])
|
|
}
|
|
h= sh.Hash();
|
|
|
|
sh = NewSHA3(SHA3_SHAKE256)
|
|
for i:=0;i<32;i++ {
|
|
sh.Process(g[i])
|
|
}
|
|
for i:=0;i<32;i++ {
|
|
sh.Process(h[i])
|
|
}
|
|
|
|
sh.Shake(ss[:],shared_secret_size)
|
|
}
|
|
|
|
func cpa_decrypt(params [6]int,SK []byte,CT []byte,SS []byte) {
|
|
ck:=params[0]
|
|
var w [KY_DEGREE]int16
|
|
var v [KY_DEGREE]int16
|
|
var r [KY_DEGREE]int16
|
|
|
|
var u= make([][KY_DEGREE]int16, ck)
|
|
var s= make([][KY_DEGREE]int16, ck)
|
|
|
|
du:=params[3]
|
|
dv:=params[4]
|
|
//shared_secret_size:=params[5]
|
|
|
|
var pos [2]int
|
|
pos[0]=0; pos[1]=0
|
|
|
|
for i:=0;i<ck;i++ {
|
|
decode(CT,du,u[i][:],pos[:])
|
|
}
|
|
decode(CT,dv,v[:],pos[:]);
|
|
for i:=0;i<ck;i++ {
|
|
decompress(u[i][:],du)
|
|
}
|
|
decompress(v[:],dv)
|
|
pos[0]=0; pos[1]=0
|
|
for i:=0;i<ck;i++ {
|
|
decode(SK,12,s[i][:],pos[:])
|
|
}
|
|
|
|
poly_ntt(u[0][:]);
|
|
poly_mul(w[:],u[0][:],s[0][:]);
|
|
for i:=1;i<ck;i++ {
|
|
poly_ntt(u[i][:])
|
|
poly_mul(r[:],u[i][:],s[i][:])
|
|
poly_add(w[:],w[:],r[:])
|
|
}
|
|
poly_reduce(w[:]);
|
|
poly_invntt(w[:]);
|
|
poly_sub(v[:],v[:],w[:]);
|
|
compress(v[:],1);
|
|
pos[0]=0; pos[1]=0;
|
|
encode(v[:],pos[:],1,SS,0);
|
|
}
|
|
|
|
func cca_decrypt(params [6]int,SK []byte,CT []byte,SS []byte) {
|
|
ck:=params[0]
|
|
du:=params[3]
|
|
dv:=params[4]
|
|
secret_cpa_key_size:=ck*(KY_DEGREE*3)/2
|
|
public_key_size:=32+ck*(KY_DEGREE*3)/2
|
|
shared_secret_size:=params[5]
|
|
ciphertext_size:=(du*ck+dv)*KY_DEGREE/8
|
|
|
|
var h [32]byte
|
|
var z [32]byte
|
|
var m [32]byte
|
|
var coins [32]byte
|
|
|
|
PK:=SK[secret_cpa_key_size:secret_cpa_key_size+public_key_size]
|
|
|
|
for i:=0;i<32;i++ {
|
|
h[i]=SK[secret_cpa_key_size+public_key_size+i]
|
|
}
|
|
for i:=0;i<32;i++ {
|
|
z[i]=SK[secret_cpa_key_size+public_key_size+32+i]
|
|
}
|
|
cpa_decrypt(params,SK,CT,m[:])
|
|
|
|
sh := NewSHA3(SHA3_HASH512)
|
|
for i:=0;i<32;i++ {
|
|
sh.Process(m[i])
|
|
}
|
|
for i:=0;i<32;i++ {
|
|
sh.Process(h[i])
|
|
}
|
|
g := sh.Hash()
|
|
|
|
for i:=0;i<32;i++ {
|
|
coins[i]=g[i+32]
|
|
}
|
|
|
|
mask:=cpa_check_encrypt(params,coins[:],PK,m[:],CT)
|
|
for i:=0;i<32;i++ {
|
|
g[i]^=(g[i]^z[i])&mask // substitute z for Kb on failure
|
|
}
|
|
|
|
sh = NewSHA3(SHA3_HASH256)
|
|
for i:=0;i<ciphertext_size;i++ {
|
|
sh.Process(CT[i])
|
|
}
|
|
hh:=sh.Hash()
|
|
|
|
sh = NewSHA3(SHA3_SHAKE256);
|
|
for i:=0;i<32;i++ {
|
|
sh.Process(g[i])
|
|
}
|
|
for i:=0;i<32;i++ {
|
|
sh.Process(hh[i])
|
|
}
|
|
sh.Shake(SS,shared_secret_size)
|
|
}
|
|
|
|
func KYBER_keypair512(r64 []byte,SK []byte,PK []byte) {
|
|
cca_keypair(PARAMS_512,r64,SK,PK)
|
|
}
|
|
|
|
func KYBER_encrypt512(r32 []byte,PK []byte,SS []byte,CT []byte) {
|
|
cca_encrypt(PARAMS_512,r32,PK,SS,CT)
|
|
}
|
|
|
|
func KYBER_decrypt512(SK []byte,CT []byte,SS []byte) {
|
|
cca_decrypt(PARAMS_512,SK,CT,SS)
|
|
}
|
|
|
|
|
|
func KYBER_keypair768(r64 []byte,SK []byte,PK []byte) {
|
|
cca_keypair(PARAMS_768,r64,SK,PK)
|
|
}
|
|
|
|
func KYBER_encrypt768(r32 []byte,PK []byte,SS []byte,CT []byte) {
|
|
cca_encrypt(PARAMS_768,r32,PK,SS,CT)
|
|
}
|
|
|
|
func KYBER_decrypt768(SK []byte,CT []byte,SS []byte) {
|
|
cca_decrypt(PARAMS_768,SK,CT,SS)
|
|
}
|
|
|
|
|
|
func KYBER_keypair1024(r64 []byte,SK []byte,PK []byte) {
|
|
cca_keypair(PARAMS_1024,r64,SK,PK)
|
|
}
|
|
|
|
func KYBER_encrypt1024(r32 []byte,PK []byte,SS []byte,CT []byte) {
|
|
cca_encrypt(PARAMS_1024,r32,PK,SS,CT)
|
|
}
|
|
|
|
func KYBER_decrypt1024(SK []byte,CT []byte,SS []byte) {
|
|
cca_decrypt(PARAMS_1024,SK,CT,SS)
|
|
}
|