co.h

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#ifndef OT_CO_H__
#define OT_CO_H__
#include "ot.h"
class OTCO: public OT<OTCO> { public:
    int cnt;
    eb_t g;
    bn_t q;
    const eb_t *gTbl;
    PRG prg;
    OTCO(NetIO * io): OT(io) {
        initialize_relic();
        eb_curve_get_gen(g);
        eb_curve_get_ord(q);
        gTbl = eb_curve_get_tab();
    }

    void send_impl(const block* data0, const block* data1, int length) {
        bn_t * a = new bn_t[length];
        eb_t * B = new eb_t[length];
        eb_t * A = new eb_t[length];
        for(int i = 0; i < length; ++i) {
            eb_newl(A[i], B[i]);
            bn_newl(a[i]);
        }

        block res[2];
        prg.random_bn(a, length);
        for(int i = 0; i < length; ++i) {
            eb_mul_fix_norm(A[i], gTbl, a[i]);
            io->send_eb(&A[i], 1);
        }

        for(int i = 0; i < length; ++i) {
            io->recv_eb(&B[i], 1);
            eb_mul_norm(B[i], B[i], a[i]);
            bn_sqr(a[i], a[i]);
            bn_mod(a[i], a[i], q);
            eb_mul_fix_norm(A[i], gTbl, a[i]);
            eb_sub_norm(A[i], B[i], A[i]);
        }

        for(int i = 0; i < length; ++i){
            res[0] = KDF(B[i]); 
            res[1] = KDF(A[i]);
            res[0] = xorBlocks(res[0], data0[i]);
            res[1] = xorBlocks(res[1], data1[i]);

            io->send_data(res, 2*sizeof(block));
        }

        for(int i = 0; i < length; ++i) {
            eb_freel(A[i], B[i]);
            bn_freel(a[i]);
        }
        delete[] a;
        delete[] A;
        delete[] B;
    }

    void recv_impl(block* data, const bool* b, int length) {
        bn_t * bb = new bn_t[length];
        eb_t * B = new eb_t[length];
        eb_t * A = new eb_t[length];
        for(int i = 0; i < length; ++i) {
            eb_newl(A[i], B[i]);
            bn_newl(bb[i]);
        }
        prg.random_bn(bb, length);

        for(int i = 0; i < length; ++i) {
            eb_mul_fix_norm(B[i], gTbl, bb[i]);
            io->recv_eb(&A[i], 1);
            if (b[i]) {
                eb_add_norm(B[i], A[i], B[i]);
            }
        }

        io->send_eb(B, length);
        for(int i = 0; i < length; ++i) {
            eb_mul_norm(A[i], A[i], bb[i]);
        }

        block res[2];
        for(int i = 0; i < length; ++i) {
            io->recv_data(res, 2*sizeof(block));
            data[i] = KDF(A[i]);
            if(b[i])
                data[i] = xorBlocks(data[i], res[1]);
            else
                data[i] = xorBlocks(data[i], res[0]);
        }
        for(int i = 0; i < length; ++i) {
            eb_freel(A[i], B[i]);
            bn_freel(bb[i]);
        }
        delete[] bb;
        delete[] A;
        delete[] B;
    }
};
#endif// OT_CO_H__