Research Article
A Random Label and Lightweight Hash-Based Security Authentication Mechanism for a UAV Swarm
Algorithm 2
The iterative algorithm of SHA-256.
1: fordo | 2: Logical function operation: | 3: S0 = (A rightrotate 2)(A rightrotate 13)(a rightrotate 22); | 4: Ma = (A and B)(A and C)(B and C); | 5: t2 = S0 + Ma; | 6: S1 = (E rightrotate 6)(E rightrotate 11)(E rightrotate 25); | 7: Ch = (E and F)((not E) and G); | 8: ; | 9: Update each word: | 10: H=G; | 11: G=F; | 12: F=E; | 13: E = D + t1; | 14: D = C; | 15: C = B; | 16: B = A; | 17: A = t1 + t2; | 18: Add the hash output of the message block to the existing hash output: | 19: h0 = h0 + A; | 20: h1 = h1 + B; | 21: h2 = h2 + C; | 22: h3 = h3 + D; | 23: h4 = h4 + E; | 24: h5 = h5 + F; | 25: h6 = h6 + G; | 26: h7 = h7 + H; | 27: Output the final hash value (big-endian): | 28: digest = hash = h0 append h1 append h2 append h3 append h4 append h5 append h6 append h7; | 29:end for | 30: return digest; |
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