Secure Service Composition with Quantitative Information Flow Evaluation in Mobile Computing Environments

. 2019 Aug 1;21(8):753. doi: 10.3390/e21080753

Algorithm 2

I n t e r_E v a l ()

Input:

s_{i + 1}

, K,

L {(X)}_{0, 1, \dots, i}

F_{0, 1, \dots, i}

Output: True or False,

L (X) 0, 1, \dots, i + 1

F_{0, 1, \dots, i + 1}

1:
retrieve cert $C e_{i + 1}$
2:
update the flows $F_{0, 1, \dots, i + 1}$ based $F_{0, 1, \dots, i}$ and $C e_{i + 1}$
3:
for each $X \in H I n_{j}, j < i + 1$ do
4:
for each $Y \in L O u t_{i + 1}$ do
5:
for each $W \in H I n_{i + 1}$ do
6:
if $(X ⇝ W) \land (W ⇝ Y) \in F_{0, 1, \dots, i + 1}$ then
7:
get the leakage $F_{L I n_{i + 1}} (W ⇝ Y)$ from the certificate $C e_{i + 1}$
8:
$L {(X)}_{i + 1}$ = $L {(X)}_{i + 1}$ + $F_{L I n_{i + 1}} (W ⇝ Y)$
9:
end if
10:
end for
11:
end for
12:
$L {(X)}_{0, 1, \dots, i + 1}$ = $L {(X)}_{0, 1, \dots, i}$ + $L {(X)}_{i + 1}$
13:
if $L {(X)}_{0, 1, \dots, i + 1} \geq K$ then
14:
return False
15:
end if
16:
end for
17:
return True