DAKEs: Decentralized Authenticated Key Exchange Protocols via Blockchain for Smart City

Algorithm 2

get

Input 

1: if version ==1 then

2:  require(users[iC].user == msg.sender);

3:  return users[iP].r[iC];

4: end if

5: if version ==2 then

6:  return users[iO].c;

7: end if

8: if version ==3 then

9:  if 100 == type then

10  return users[iO].token1;

11: end if

12: if 200 == type then

13:  return users[iO].token2;

14: end if

15: if 300 == type then

16:  return users[iO].c;

17: end if

18:end if