// Multipairing void do_multi(int m){ int i = 0; lpoly list[m]; lpoly *tmp_list; // prevalues element_t gg[m]; element_ptr ggg[m]; element_t hh[m]; for(i = 0; i < m; i++){ element_init_G2(gg[i], pairing); element_random(gg[i]); ggg[i] = malloc(sizeof(element_ptr)); element_init(ggg[i], gg[i]->field); element_set(ggg[i], gg[i]); element_init_G1(hh[i], pairing); element_random(hh[i]); } // precomputation gettimeofday(&tvBegin, NULL); for(i = 0; i < m; i++){ tmp_list = lpoly_init(); precompute(tmp_list, pairing->r, hh[i], gg[i]); list[i] = *tmp_list; } gettimeofday(&tvEnd, NULL); timeval_subtract(&tvEnd, &tvBegin, 1000); // compute gettimeofday(&tvBegin, NULL); compute_millers(temp2, list, ggg, m, pairing); gettimeofday(&tvEnd, NULL); timeval_subtract(&tvEnd, &tvBegin, 1000); gettimeofday(&tvBegin, NULL); element_prod_pairing(temp1, hh, gg, m); gettimeofday(&tvEnd, NULL); timeval_subtract(&tvEnd, &tvBegin, 1000); for(i = 0; i < m; i++){ lpoly_free2(list[i]); } }
void pbc_decrypt(struct crypto *pbc, int tl, int *nse, int ts, int use_caching, int use_product) { /* e(C_0, K_0) -> pairing(C, K[i]) * e(C_{i1}, K_{i1}) -> pairing(Ci[i], Ki[i]) * e(C_{i2}, K_{i2}) -> pairing(Ci[i], Ki[i]) */ element_t C, K[ts], Ci[tl], Ki[tl], R, A, B, M, T; int num_mul=0, num_pair=0; struct timeval st, en; int i, j; /* -------------------- setup --------------------- */ gettimeofday(&st, NULL); element_init_G1(C, pbc->pairing); element_random(C); for (i = 0; i < ts; i++) { element_init_G2(K[i], pbc->pairing); element_random(K[i]); } for (i = 0; i < tl; i++) { element_init_G1(Ci[i], pbc->pairing); element_random(Ci[i]); } for (i = 0; i < tl; i++) { element_init_G2(Ki[i], pbc->pairing); element_random(Ki[i]); } element_init_GT(R, pbc->pairing); element_init_GT(A, pbc->pairing); element_init_GT(B, pbc->pairing); element_init_GT(M, pbc->pairing); element_init_GT(T, pbc->pairing); gettimeofday(&en, NULL); printf("Setup: %lu us\n", time_diff(&st, &en)); printf("tl=%d ts=%d|", tl, ts); for (i = 0; i < ts; i++) printf("%d ", nse[i]); printf("\n"); /* ------------------ decryption ------------------ */ gettimeofday(&st, NULL); /* e(C0, K0) across all tokens */ if (use_caching) { pairing_pp_t pp; pairing_pp_init(pp, C, pbc->pairing); for (i = 0; i < ts; i++) pairing_pp_apply(R, K[i], pp); pairing_pp_clear(pp); } else for (i = 0; i < ts; i++) { pairing_apply(R, C, K[i], pbc->pairing); num_pair++; } /* prod{e(Ci1, Ki1)}prod{e(Ci2, Ki2)} across all tokens */ if (use_product) { for (i = 0; i < ts; i++) { if (!nse[i])continue; element_prod_pairing(A, Ci, Ki, nse[i]); element_prod_pairing(B, Ci, Ki, nse[i]); element_mul(M, A, B); } } else for (i = 0; i < ts; i++) { element_set1(A); for (j = 0; j < nse[i]; j++) { element_pairing(T, Ci[j], Ki[j]); element_mul(A, A, T); num_pair++; num_mul++; } element_set1(B); for (j = 0; j < nse[i]; j++) { element_pairing(T, Ci[j], Ki[j]); element_mul(B, B, T); num_pair++; num_mul++; } element_mul(M, A, B); num_mul++; } gettimeofday(&en, NULL); printf("Decryption: %lu us\n", time_diff(&st, &en)); if (use_caching || use_product) { num_pair = -1; num_mul = -1; } printf("Used %d pairings and %d multiplications\n", num_pair, num_mul); /* ------------------- cleanup -------------------- */ gettimeofday(&st, NULL); element_clear(T); element_clear(M); element_clear(B); element_clear(A); element_clear(R); element_clear(C); for (i = 0; i < ts; i++) element_clear(K[i]); for (i = 0; i < tl; i++) element_clear(Ci[i]); for (i = 0; i < tl; i++) element_clear(Ki[i]); gettimeofday(&en, NULL); printf("Cleanup: %lu us\n", time_diff(&st, &en)); }