static int mulg_item_count(element_ptr e) {
return element_item_count(e->data);
}
bool Manager::JoinMember(string request, string & respond)
{
//elements
element_t Pi1;
element_t Pi2;
element_t Sk;
element_t R;
element_init_G1(Pi1,pairing);
element_init_GT(Pi2, pairing);
element_init_Zr(Sk, pairing);
element_init_G1(R,pairing);
//read & check SoK
string hash;
string hash_check;
RequestFromString(request,hash,Sk,Pi1);
//check Pi1 is point of curve
if(element_item_count(Pi1)!=2)
{
element_clear(Pi1);
element_clear(Pi2);
element_clear(Sk);
element_clear(R);
return 1;//failure
}
element_t tmp1, tmp2;
element_t c_Hsok;
element_init_G1(tmp1, pairing);
element_init_G1(tmp2, pairing);
element_init_Zr(c_Hsok, pairing);
element_from_hash(c_Hsok,(void*)hash.c_str(),hash.length());
element_pow_zn(tmp1,g,Sk);
element_pow_zn(tmp2,Pi1,c_Hsok);
element_div(R,tmp1,tmp2);
hash_check=Helper::Hash_g_R(g,R);
if(hash.compare(hash_check))
{
element_clear(Pi1);
element_clear(Pi2);
element_clear(Sk);
element_clear(R);
element_clear(tmp1);
element_clear(tmp2);
element_clear(c_Hsok);
return 1;//failure
}
//generate r_issuer
element_t issuer_r;
element_init_Zr(issuer_r, pairing);
element_random(issuer_r);
//create a b c
element_t ai;
element_t bi;
element_t ci;
element_t temp_ci1;
element_t temp_ci2;
//init
element_init_G1(ai, pairing);
element_init_G1(bi, pairing);
element_init_G1(ci, pairing);
element_init_G1(temp_ci1, pairing);
element_init_G1(temp_ci2, pairing);
//compute ai bi ci
element_pow_zn(ai,g,issuer_r);//ai
element_pow_zn(bi,ai,y);//bi
element_pow_zn(temp_ci1,ai,x);
element_pow_zn(temp_ci2,Pi1,issuer_r);
element_pow_zn(temp_ci2,temp_ci2,x);
element_pow_zn(temp_ci2,temp_ci2,y);
element_mul(ci,temp_ci1,temp_ci2);//ci
//create RESPOND
respond=MemberSecretToString(ai,bi,ci);
//compute Pi2
element_pairing(Pi2,Pi1,g);
//Write_to_reg_list
AddToRegistrationList(Pi1, Pi2);
//clear elements
element_clear(issuer_r);
element_clear(Pi1);
element_clear(Pi2);
element_clear(temp_ci1);
element_clear(temp_ci2);
element_clear(tmp1);
element_clear(tmp2);
element_clear(c_Hsok);
element_clear(Sk);
element_clear(R);
element_clear(ai);
element_clear(bi);
element_clear(ci);
return 0;//success
}
