SM4 DFA: differential fault analysis attacks (DFA) against SM4

Introduction

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Simple DFA on SM4 round31, round30, round29 and round 28.

And recover the master key by these four round keys.

Ref:

Ruilin Li, Bing Sun, Chao Li, Jianxiong You, Differential Fault Analysis on SMS4 using a single fault, Information Processing Letters, Volume 111, Issue 4, 2011, Pages 156-163, ISSN 0020-0190,

https://doi.org/10.1016/j.ipl.2010.11.011.

张蕾,吴文玲.SMS4密码算法的差分故障攻击[J].计算机学报,2006(09):1596-1602.

https://kns.cnki.net/kcms/detail/detail.aspx?dbcode=CJFD&dbname=CJFD2006&filename=JSJX200609011&v=xAkChrfMKVAUb6xQPrdHbTHWM98SnCwCOA9gyxNS4qm3YEcyZUB00vqmQY1zUibw

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Usage

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Script should be run under python3.

test function:

def foo():
    masterKey = b'\x01\x23\x45\x67\x89\xab\xcd\xef\xfe\xdc\xba\x98\x76\x54\x32\x10'
    in_put = b'\x01\x23\x45\x67\x89\xab\xcd\xef\xfe\xdc\xba\x98\x76\x54\x32\x10'
    # last_round_key = [k31, k30, k29, k28]
    #last_round_key = [0x9124a012, 0x01cf72e5 ,0x62293496, 0x428d3654]

    sk = set_key(masterKey, SM4_ENCRYPT)
    #print("fault output:")
    r31 = [gen_fault_cipher(in_put, sk, 31) for i in range(30)]
    r30 = [gen_fault_cipher(in_put, sk, 30) for i in range(30)]
    r29 = [gen_fault_cipher(in_put, sk, 29) for i in range(30)]
    r28 = [gen_fault_cipher(in_put, sk, 28) for i in range(30)]
    ref = sm4_encrypt(in_put, sk)
    last_round_key = []
    key_schedule = []
    last_round_key.append(crack_round(r31,ref))
    last_round_key.append(crack_round(r30,ref,last_round_key))
    last_round_key.append(crack_round(r29,ref,last_round_key))
    last_round_key.append(crack_round(r28,ref,last_round_key))
    key_schedule = recovery_key(last_round_key)
    MK = get_masterKey(key_schedule)
    dump_byte(MK)

Faulty ciphers are generated by gen_fault_cipher()

Also, you can get the faulty cipher from other sources.

Run the script:

    python3 ./sm4_dfa.py

Result:

Master Key found:
/x01/x23/x45/x67/x89/xab/xcd/xef/xfe/xdc/xba/x98/x76/x54/x32/x10