37 lines
1.3 KiB
C
37 lines
1.3 KiB
C
/*
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* Copyright (C) 2014 FH Bielefeld
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*
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* This file is part of a FH Bielefeld project.
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
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* MA 02110-1301 USA
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*/
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// Require: N , q, p, secret key f , inverse polynomial Fp , and encrypted message e.
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int ntru_decrypt(char *encr_msg, pb_poly *private_key, ntru_context *context, char ** decr_msg){
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// StarMultiply(f, e, a, N, q)
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for(int i = 0, i < N, i++){
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if(a[i] < 0 ) {
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a[i] = a[i] + q; // Make all coefficients positive
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}
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if(a[i] > q/2) {
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a[i] = a[i] - q // Shift coefficients of a into range (−q/2, q/2)
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}
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}
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// StarMultiply(a, Fp , d, N, p)
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// {Decode returns the decrypted message, d, through the argument list.}
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return 0;
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}
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