Research Article

Automatic Search for the Linear (Hull) Characteristics of ARX Ciphers: Applied to SPECK, SPARX, Chaskey, and CHAM-64

Table 2

The 9/10/13 round optimal linear trails for SPECK32/48/64.

rSPECK32SPECK48SPECK64

000A0062 F1000180B80001101000120140100212
178B818B94000000C00001000018100200001011
200906021100000E00000 E200000100000000010
36080408117A0070700070500000001000000001
4008000010C2C08082938060D0000000C0000002
5000100001D00000108300260610000606C00003
60B0008003800000809800100024D0300620C036
720402050200000400C0041181070141B1073586
8008380C31200020260020200130018180318403
9170B130A013100310100218180000001812002
108800A888010900180000000010001
1100001000000000001
1200000098000000802
135000040480000404