CN114531223A - Encryption and decryption method based on lightweight block cipher tenon type algorithm - Google Patents

Abstract

An encryption and decryption method based on a lightweight block cipher tenon (Tenon) algorithm, by dividing the data to be encrypted into equal-length plaintext blocks P according to the block length of each group of n bits, and setting a master key K with a length of m ₁ Bit, the master key K generates the round key of the Tenon block cipher algorithm through the key arrangement algorithm

1≤r≤30, the length is m ₂ bits, m ₁ =128, m ₂ =64, in the encryption process, the input to-be-encrypted data is subjected to R rounds of iterative encryption operations, and an n-bit ciphertext block C is output. The present invention comprehensively considers security and implementation cost, based on SPN structure design, can realize efficient, safe and lightweight Tenon block cipher algorithm, and is suitable for application in resource-limited equipment.

Description

Encryption and decryption method based on lightweight block cipher tenon algorithm

technical field

The invention relates to a technology in the field of information security, in particular to an implementation method of a lightweight block cipher tenon (Tenon) algorithm.

Background technique

Existing block cipher algorithms require complex operations and structures to achieve the best security under known conditions, but consume a lot of hardware and software resources, making the algorithm implementation slow and difficult to apply to micro IoT devices. However, if a too simple logical structure is used, it is difficult to meet the requirements in terms of security.

SUMMARY OF THE INVENTION

Aiming at the above-mentioned shortcomings of the prior art, the present invention proposes an encryption and decryption method based on a lightweight block cipher tenon algorithm, which comprehensively considers security and implementation cost, and is designed based on SPN structure, which can achieve high efficiency, safety, and light weight. The Tenon block cipher algorithm is suitable for application on resource-constrained devices.

The present invention is achieved through the following technical solutions:

The present invention relates to an encryption method based on a lightweight block cipher tenon algorithm, comprising:

Step 1) divide the data to be encrypted into equal-length plaintext groups P according to the grouping length of each group of n bits, n=64;

长度为m₂比特，m₁＝128，m₂＝64，具体为：对于第r轮轮密钥，将128比特主密钥的第

位依次赋值给64比特长度的轮密钥

如对于第1轮，将主密钥的第1,2,4,7，…,97比特依次赋给轮密钥的第0,1,2，…,63位。再将

按16比特长度依次划分为4组

对于轮数r，将其表示为5位二进制数，最右侧为低位：如对于轮数r＝11，表示为01011。之后进行：1.将轮密钥中的第15,16,31,47,63位与r的二进制表示的五位依次进行与操作，结果更新为新的k₁₅,k₁₆,k₃₁,k₄₇,k₆₃；2.将

的16比特进行按位取反得到新的k₃₂k₃₃…k₄₇；3.将k₄₈k₄₉…k₆₃与k₃₂k₃₃…k₄₇按位与操作后，再与k₀k₁…k₁₅按位进行异或操作得到新的k₄₈k₄₉…k₆₃。更新完成后的64比特k₀k₁…k₆₃按16比特长度分为4组

即为第r轮的轮密钥，并将主密钥更新为128比特的

Step 2) Set the master key K, the length is m ₁ bit, and the round key of the Tenon block cipher algorithm is generated by the master key K through the key arrangement algorithm

The length is m ₂ bits, m ₁ =128, m ₂ =64, specifically: for the rth round key, the 128-bit master key

Bits are sequentially assigned to the round key of 64-bit length

For example, for the first round, assign the 1st, 2nd, 4th, 7th, ..., 97th bits of the master key to the 0th, 1st, 2nd, ..., 63rd bits of the round key in sequence. again

Divided into 4 groups according to the length of 16 bits

For the number of rounds r, it is represented as a 5-bit binary number, and the lowermost bit is on the far right: for example, for the number of rounds r=11, it is represented as 01011. Then proceed: 1. Perform the AND operation on the 15th, 16th, 31st, 47th, 63rd bits in the round key and the five bits of the binary representation of r in turn, and update the results to new k ₁₅ , k ₁₆ , k ₃₁ , k ₄₇ ,k ₆₃ ; 2. will

Perform bitwise inversion of the 16 bits to obtain new k ₃₂ k ₃₃ ... k ₄₇ ; 3. After k ₄₈ k ₄₉ ... k ₆₃ and k ₃₂ k ₃₃ ... k ₄₇ are bitwise ANDed with k ₀ k ₁ ... k ₁₅ performs bitwise XOR operation to obtain new k ₄₈ k ₄₉ . . . k ₆₃ . After the update is completed, the 64-bit k ₀ k ₁ ... k ₆₃ is divided into 4 groups according to the length of 16 bits

is the round key of the rth round, and the master key is updated to a 128-bit

Step 3) In the encryption process, the input data to be encrypted is subjected to R rounds of iterative encryption operation operations, and the ciphertext is output, specifically:

3.1) For R=1, 2, 3, ..., 29 rounds, in each round of encryption operation: add the n-bit plaintext block P and the m ₂ -bit round key K _i of the i-th round to the round key. , which is divided into 8 8-bit bytes, which are sequentially replaced by the nonlinear layer S box, and after the linear layer replacement, the output data is used as the input of the next round.

The positive integer n=64; m ₁ =128; m ₂ =64; R=30;

从高位到低位表示为{k₀,k₁,k₂,k₃,…,k₆₁,k₆₂,k₆₃}，按位将P_i与k_i(0≤i≤63)进行异或得到新的明文分组P＝{P₀,P₁,P₂,…,P₆₂,P₆₃}；The specific implementation of the round key addition is as follows: the 64-bit plaintext packet P input in each round is expressed as {P ₀ , P ₁ , P ₂ ,..., P ₆₂ , P ₆₃ } from high order to low order, and the rth round 64 bit round key

It is expressed as {k ₀ ,k ₁ ,k ₂ ,k ₃ ,...,k ₆₁ ,k ₆₂ ,k ₆₃ } from the high order to the low order, and the bitwise XOR of P _i and k _i (0≤i≤63) is obtained New plaintext packet P={P ₀ , P ₁ , P ₂ ,...,P ₆₂ ,P ₆₃ };

The specific implementation of the above-mentioned non-linear layer S-box replacement is as follows: the _plaintext P ₌ {P ₀ , P ₁ , P ₂ , . Divide each 8 bits into a group to obtain 8 byte groups of 8 bits, denoted as W ₀ , W ₁ , W ₂ , W ₃ , W ₄ , W ₅ , W ₆ , W ₇ , where _Wi = { w _8i+0 ,w _8i+1 ,w _8i+2 ,w _8i+3 ,w _8i+4 ,w _8i+5 ,w _8i+6 ,w _8i+7 }, 0≤i≤7, set W ₀ ,W ₁ ,W ₂ ,W ₃ ,W ₄ ,W ₅ ,W ₆ ,W ₇ pass through 8 juxtaposed S-boxes at the same time, the specific process is to take eight identical 8-bit input and 8-bit output S-box transformation , the transformation is to take Wi as 8-bit input and obtain a new 8-bit output through S-box operation W′ _{i =} {w′ _8i+0 ,w′ _8i+1 ,...,w′ _8i+6 ,w′ _8i+7 }=S(W _i )=S({w _8i+0 , w _8i+1 , . . . , w _8i+6 , w _8i+7 }). This Tenon algorithm S-box is constructed based on 8-level NFSR (Non-Linear Feedback Shift Register). One S-box operation requires 11 iterations. The output of the previous beat will be used as the input of the next beat. The input is used as the first bit of the output; the third bit of the input is inverted and then ANDed with the eighth bit, and then XORed with the fifth bit and the sixth bit respectively to obtain the second bit of the output; the first bit of the input Two bits as the third bit of the output; the eighth bit of the input as the fourth bit of the output; the sixth bit of the input as the seventh bit of the output; the fourth bit of the input as the sixth bit of the output; the third bit of the input As the output seventh bit; the input sixth bit is first ANDed with the eighth bit and then XORed with the first bit and the fifth bit to obtain the output eighth bit. The 8 juxtaposed S-boxes are respectively output as W′ ₀ , W′ ₁ , W′ ₂ , W′ ₃ , W′ ₄ , W′ ₅ , W′ ₆ , W′ ₇ after the above-mentioned 11-beat operation. Its combination from high order to low order is 64 bits C={C ₀ , C ₁ , C ₂ , . . . , C ₆₂ , C ₆₃ };

The over-linear layer replacement is specifically: performing bit-level pull-wire replacement on the 64 bits after the nonlinear layer S-box replacement operation. The specific process is that 64 bits replace the output 8 bits to the new position in the order of 8 S boxes: the 8-bit output of W _i after one S box replacement is W′ _i ={w′ _8i+0 ,w′ _{8i+ 1} ,w′ _8i+2 ,w′ _8i+3 ,w′ _8i+4 ,w′ _8i+5 ,w′ _8i+6 ,w′ _8i+7 } are transformed into

{C _{[8(i+1)]mod64+(2i+1)mod8} ,C _{[8(i+2)]mod64+(2i+2)mod8} ,C _{[8(i+3)]mod64+(2i+3) mod8} ,C _{[8(i+4)]mod64+(2i+4)mod8} ,C _{[8(i+5)]mod64+(2i+5)mod8} ,C _{[8(i+6)]mod64+(2i+6 )mod8} ,C _{[8(i+7)]mod64+(2i+7)mod8} ,C _{[8(i+8)]mod64+(2i+8)mod8} }, where 0≤i≤7.

3.2) For R=30 rounds, add the n-bit group P and the round key K _i of the i-th round of m ₂ bits to the round key, divide it into 8 8-bit bytes, and pass through the nonlinear layer. The S box is replaced, and the final 64-bit ciphertext block C is directly output.

The present invention relates to a decryption method of the above encryption method, including: key arrangement algorithm generating round key, nonlinear layer inverse S-box substitution, round key addition and linear layer inverse permutation.

The described key arrangement algorithm is the same as step 2) in the encryption process; instead of the nonlinear layer inverse S box, the 64-bit ciphertext group C is divided into 8 groups according to the 8-bit width, and the i-th group is denoted as W′ _i = { w′ _8i+0 ,w′ _8i+1 ,w′ _8i+2 ,w′ _8i+3 ,w′ _8i+4 ,w′ _8i+5 ,w′ _8i+6 ,w′ _8i+7 },0 ≤i≤7, replace W′ _i through the inverse S box to obtain W _i , wherein the selected inverse S box is described in the specific embodiment; the round key addition operation is the same as the round key addition described in step 3.1; the linear layer The inverse transformation is to group the ciphertext of C {C _{[8(i+1)]mod64+(2i+1)mod8} ,C _{[8(i+2)]mod64+(2i+2)mod8} ,C _{[8(i+ 3)]mod64+(2i+3)mod8} ,C _{[8(i+4)]mod64+(2i+4)mod8} ,C _{[8(i+5)]mod64+(2i+5)mod8} ,C _{[8(i +6)]mod64+(2i+6)mod8} ,C _{[8(i+7)]mod64+(2i+7)mod8} ,C _{[8(i+8)]mod64+(2i+8)mod8} } transform to W′ _i ={w′ _8i+0 ,w′ _8i+1 ,w′ _8i+2 ,w′ _8i+3 ,w′ _8i+4 ,w′ _8i+5 ,w′ _8i+6 ,w′ _8i+7 }, which is the opposite of the pull-wire replacement chosen during encryption.

For R=30, the ciphertext block C only needs to undergo two operations of inverse S-box substitution and round key addition; for 1≤R≤29, the decryption process needs to perform linear layer inverse permutation, inverse S-box substitution and round key in turn. The key is added three times, and finally the correct plaintext packet P is obtained.

technical effect

The 8-bit nonlinear layer S box used in the present invention is designed based on the nonlinear feedback shift register, which can significantly reduce the hardware implementation cost; in terms of cryptographic properties, the differential uniformity is 8 and the nonlinearity is 96; the selected linear transformation and Compared with the transformation used in the PRESENT algorithm, the position of 64 bits can be changed after permutation to prevent potential weaknesses caused by fixed points; the key arrangement algorithm adopts a non-linear arrangement, which increases security.

Description of drawings

1 is a schematic diagram of the single-shot structure of the nonlinear feedback shift register used in the S box of the present invention;

Fig. 2 is a schematic diagram of the replacement of the linear layer cable used in the present invention;

Figure 3 is a flow chart of the present invention.

Detailed ways

为第r轮的轮密钥，长度64比特，r＝1,2,…,30，P_i为明文分组由高位到低位的第i比特，i＝0,1,2,…,62,63，K_i为主密钥由高位到低位的第i比特，i＝0,1,2,…,126,127，k_i为轮密钥由高位到低位的第i比特，i＝0,1,2,…,62,63，

为密钥扩展中使用的64比特轮密钥中16比特过程字，i＝0,1,2,3，

为最终输出的64比特轮密钥中的16比特字，

W_i为进入S盒替换前的状态字，每个字的长度为8比特，i＝0,1,…,6,7，W′_i为经过S盒替换后的状态字，每个字的长度为8比特，i＝0,1,…,6,7，S为长度为16比特的全1序列，

为比特级异或运算，&为比特级与运算，||为字符串连接符，本发明Tenon算法基于SPN结构设计，实现过程主要分为S盒代替(非线性层)和拉线置换(线性层)两部分。As shown in Figure 3, the SPN structure is adopted in this embodiment, the block length is 64 bits, the key length is 128 bits, the number of algorithm iteration rounds is 30, P is a 64-bit plaintext block, C is a 64-bit ciphertext block, and R is a 64-bit ciphertext block. The number of iteration rounds of the algorithm, r is the current round of the algorithm, _1≤r≤30 , ri is the binary representation of the current round number, 1≤r≤30, 0≤i≤4, K is the 128-bit master key,

is the round key of the rth round, with a length of 64 bits, r=1,2,...,30, P _i is the i-th bit of the plaintext packet from high to low, i=0,1,2,...,62,63 , K _i is the i-th bit of the master key from high to low, i=0,1,2,...,126,127, ki is the _i -th bit of the round key from high to low, i=0,1,2 ,…,62,63,

is the 16-bit process word in the 64-bit round key used in key expansion, i=0, 1, 2, 3,

is the 16-bit word in the final output 64-bit round key,

W _i is the status word before entering the S box replacement, the length of each word is 8 bits, i=0,1,...,6,7, W' _i is the status word after the S box replacement, the length of each word is The length is 8 bits, i=0,1,...,6,7, S is an all-one sequence with a length of 16 bits,

is a bit-level XOR operation, & is a bit-level AND operation, and || is a string connector. The Tenon algorithm of the present invention is designed based on the SPN structure. ) in two parts.

As shown in Figure 1, the present embodiment relates to a method for implementing a lightweight block cipher algorithm, comprising the following steps:

Step 1. Group the data to be encrypted to be encrypted according to the length of 64 bits, encrypt each group separately, and record a group of data to be encrypted as P; set the master key, the length of the master key is 128 bits, and expand according to the key. The algorithm obtains a round key with a length of 64 bits, and the rth round key is recorded as

长度为m₂比特，m₁＝128，m₂＝64，其中Tenon算法的密钥编排算法如下：对于r＝1,2,…,30,取128比特主密钥K的第

位：

共64比特，按序依次赋给

Step 2. Set the master key K, the length is m ₁ bit, and the round key of the Tenon block cipher algorithm is generated by the master key K through the key arrangement algorithm

The length is m ₂ bits, m ₁ =128, m ₂ =64, and the key arrangement algorithm of Tenon algorithm is as follows: For r=1,2,...,30, take the first 128-bit master key K

Bit:

A total of 64 bits, assigned in order

以16比特长度划分为4组，记为

计算：

输出当前轮密钥

主密钥更新为

再进行下一轮轮密钥的计算。The current round number r is expressed as r ₀ , r ₁ , r ₂ , r ₃ , r ₄ in 5-bit binary numbers, and k ₁₅ = k ₁₅ &r ₀ ; k ₁₆ = k ₁₆ &r ₁ ; k ₃₁ = k ₃₁ &r ₂ ; k ₄₇ =k ₄₇ &r ₃ ; k ₆₃ =k ₆₃ &r ₄ ; will be obtained

Divided into 4 groups with a length of 16 bits, denoted as

calculate:

Output current round key

Master key updated to

Then perform the calculation of the next round key.

Step 3) In the encryption process, the input data to be encrypted is subjected to R rounds of iterative encryption operations, and the ciphertext is output. For R=1, 2, 3, ..., 29 rounds, in each round of encryption operations: n After the bit plaintext packet P and the m ₂ -bit round key K _i of the i-th round are round key added, it is divided into 8 8-bit bytes, which are sequentially replaced by the nonlinear layer S box, and after the linear layer replacement , the output data is used as the input of the next round. The specific process is as follows: divide the plaintext block and the round key into P ₀ , P ₁ ,...,P ₆₂ ,P ₆₃ and k ₀ ,k ₁ ,...,k according to the bit order ₆₂ ,k ₆₃ , for i=0,1,2,3,4,5,6,7, calculate

w′₂＝w₁；w′₃＝w₇；w′₄＝w₆；w′₅＝w₃；w′₆＝w₂；

w′₀w′₁w′₂w′₃w′₄w′₅w′₆w′₇作为新的w₀w₁w₂w₃w₄w₅w₆w₇,进入下一拍。；也可以将各状态字W_i以10进制表示，通过查找S盒真值表，再转为二进制表示，得到新的状态字W′_i，0≤i≤7。The non-linear layer S-box substitution operation is specifically: dividing the new plaintext packet obtained by adding the round key into 8 state words, each state word having a length of 8 bits, that is, P=W ₀ ||W ₁ | |W ₂ |W ₃ ||W ₄ ||W ₅ ||W _{6 ||} W ₇ ; for Wi, convert it through an 8-bit in 8-bit out S-box to obtain a new 8-bit state word W _i '. Each transformation needs to iterate 11 beats, and the process of each beat includes: w′ ₀ =w ₅ ;

w' ₂ =w ₁ ; w' ₃ =w ₇ ; w' ₄ =w ₆ ; w' ₅ =w ₃ ; w' ₆ =w ₂ ;

w′ ₀ w′ ₁ w′ ₂ w′ ₃ w′ ₄ w′ ₅ w′ ₆ w′ ₇ as the new w ₀ w ₁ w ₂ w ₃ w ₄ w ₅ w ₆ w ₇ , enter the next beat. ; It is also possible to represent each state word W _i in decimal system, by searching the truth table of the S box, and then converting it into binary representation to obtain a new state word W' _i , 0≤i≤7.

所采用S盒真值表十进制表示为{0,191,119,88,130,86,165,114,57,77,91,139,148,132,200,84,34,120,180,209,203,42,234,249,61,236,223,192,18,195,21,95,121,219,122,11,221,123,31,60,163,7,112,246,46,55,56,194,210,102,116,143 ,47,45,173,224,63,141,190,201,17,25,157,133,205,87,28,147,152,30,64,158,129,248,125,182,176,188,154,100,159,230,105,153,103,5,8,89,73,92,107,247,241,238,174,26,229,81,2,104,43,49,227,137,68,212,211,66,251,127,242,76,189,94,111,109,235,36,70,169 ,14,78,183,22,170,23,214,74,255,250,231,1,79,85,110,178,150,96,240,71,69,29,51,93,185,144,145,12,215,33,217,175,135,166,161,59,155,118,24,75,13,131,128,156,115,228,186,54,149,196,98,167,37,138,67,237,233,207,99,126,216,254 ,58,3,136,140,41,97,6,53,225,164,39,181,162,38,19,253,83,142,90,171,220,198,226,52,27,199,101,80,218,239,117,9,50,48,108,124,206,15,252,177,208,35,44,62,151,245,168,243,10,222,32,244,179,193,65,134,232,72,213,202,113,160 , 20, 187, 4, 204, 106, 184, 172, 16, 197, 146, 40, 82}.

The 8 state words W ₀ ′||W ₁ ′||W ₂ ′||W ₃ ′||W ₄ ′||W ₅ ′||W ₆ ′||W ₇ ′ obtained from the nonlinear layer are converted from The high-order to low-order bits are arranged in bit order to obtain 64 bits C={C ₀ , C ₁ , C ₂ , . . . , C ₆₂ , C ₆₃ }.

The linear layer permutation operation described in step 5 is as follows:

The 64 bits after the non-linear layer S-box replacement operation are subjected to bit-level pull-wire replacement. The specific process is that 64 bits replace the output 8 bits to the new position in the order of 8 S boxes: the 8-bit output of W _i after one S box replacement is obtained W′ _I ={C _8i+0 ,C _8i+1 , C _8i+2 , C _8i+3 , C _8i+4 , C _8i+5 , C _8i+6 , C _8i+7 } transform to obtain the next round of input plaintext packets, which is {P _{[8(i+1) ]mod64+(2i+1)mod8} ,P _{[8(i+2)]mod64+(2i+2)mod8} ,P _{[8(i+3)]mod64+(2i+3)mod8} ,P _{[8(i+4 )]mod64+(2i+4)mod8} ,

P _{[8(i+5)]mod64+(2i+5)mod8} ,P _{[8(i+6)]mod64+(2i+6)mod8} ,P _{[8(i+7)]mod64+(2i+7)mod8} ,P _{[8(i+8)]mod64+(2i+8)mod8} }, where 0≤i≤7.

Table 1 shows the linear layer permutation correspondence.

For the 30th round, the linear layer permutation operation is not performed, and the 8 state words after the S-box substitution operation are directly combined into the final ciphertext output in sequence, that is, C=W ₀ ′||W ₁ ′||W ₂ ′ ||W ₃ ′||W ₄ ′||W ₅ ′||W ₆ ′||W ₇ ′.

The decryption process in steps 4 and 5 is as follows:

对于r＝1,2,3,…,30,重复执行下列操作。Extend the 128-bit master key K into a 64-bit wheel key according to the key arrangement algorithm

For r=1, 2, 3, . . . , 30, the following operations are repeated.

The ciphertext is grouped with a fixed length of 64 bits, and each ciphertext block C is divided into eight 8-bit length state words W ₀ ′||W ₁ ′||W ₂ ′||W ₃ ′|| W ₄ ′||W ₅ ′||W ₆ ′||W ₇ ′.

For each state word W' _i , a new state word W _i is obtained through the inverse S-box substitution operation, 0≤i≤7.逆S盒的十进制表示为：{0,131,98,183,246,85,188,41,86,213,230,35,147,160,120,219,251,60,28,196,244,30,123,125,158,61,95,206,66,141,69,38,232,149,16,223,117,172,195,192,254,186,21,100,224,53,44,52,215,101,214,142,205,189,167,45,46 ,8,182,155,39,24,225,56,70,236,107,174,104,140,118,139,239,88,127,159,111,9,121,132,209,97,255,198,15,133,5,65,3,87,200,10,89,143,113,31,137,187,170,178,79,208,49,84,99,82,248,90,216,115,134,114,42,242,7,164,50,212,157 ,2,17,32,34,37,217,74,179,109,162,72,4,161,13,63,237,152,184,103,173,11,185,57,199,51,145,146,253,67,12,168,136,226,68,83,78,156,163,62,71,80,243,154,194,40,191,6,153,171,228,119,124,201,250,54,94,151 ,76,221,135,234,18,193,75,122,249,144,166,245,77,112,58,1,27,235,47,29,169,252,203,207,14,59,241,20,247,64,218,177,222,19,48,106,105,240,126,148,180,150,210,33,202,36,231,26,55,190,204,102,165,96,81,130,238,176,22,116,25,175,93,211,138,92,110,229,233,227 ,43,91,73,23,129,108,220,197,181,128}

The obtained new 8 state words Wi are arranged and combined in sequence into a 64-bit group P={P ₀ , P ₁ , P ₂ , . . . , P ₆₂ , P _{63 }} .

The round key addition refers to: the current round key K _r is recorded as K _r ={k ₀ ,k ₁ ,k ₂ ,...,k ₆₃ } in the order from high to low. For i=0, 1,…,63, calculate:

The inverse linear layer permutation refers to: P={P ₀ , P ₁ , P ₂ ,..., P ₆₂ , P ₆₃ } obtained after adding the round key is subjected to the pull-wire permutation inverse to the encryption operation to obtain the next step. C = {C ₀ , C ₁ , C ₂ , . . . , C ₆₂ , C ₆₃ } for a round.

Table 2 shows the linear layer permutation correspondence in the decryption process.

After specific practical experiments, when the 128-bit master key is set to all 0s (0000 0000 0000 00000000 0000 0000 0000), the keys of each round are (in hexadecimal notation):

Round 01: 0000 0000 FFFF 0000

Round 02: 0002 0420 FDF6 0816

Round 03: 0000 0CB0 BDB2 2C90

Round 04: 0020 252B 3F73 1430

Round 05: 0302 4861 65B7 0713

Round 06: C04E 4525 D5F8 D026

Round 07: 185A 00DC 4DC5 105F

Round 08: 72A0 85A6 453F 73A8

Round 09: 460A 4316 F0D5 561E

Round 10: 01B2 2526 94D7 0136

11 rounds: AD40 6A88 DA87 A5C7

12 rounds: 1802 C2CC 2E6D 3006

Round 13: 6420 012964BB 2423

Round 14: 0228 440F 9E37 8228

15 rounds: 147C 4622 77F7 367F

Round 16: 590E 0B76 5DB5 41BA

Round 17: 3E02 2EC4 CEE7 FC81

Round 18: B2DC 48A4 1703 B3DC

Round 19: 4EC7 58FC C49C CAD3

20 rounds: 9740 265B 3109 B648

Round 21: DF8C 6F09 3E03 ED8F

Round 22: DB6E 3529 A3E2 F9CC

Round 23: ABE6 19CF C4AF 6B45

24 rounds: DD01 4CE0 A0C3 7DC3

25 rounds: D805 E5A8 E0F3 3896

26 rounds: 8ABB 560E EEF3 2EE9

Round 27: 625F A074 8437 667D

Round 28: 7A48 DA2F 0003 7A48

Round 29: FCB2 8FA6 6859 FCBA

30 rounds: 8DE9 CC93 4885 856D

Algorithm encryption test vector (TestVector): When the master key is all 1s and all 0s, respectively, and the plaintext data is all 1s and all 0s, respectively, calculate the ciphertext data. Table 3 is the test vector (hexadecimal notation) of the Tenon algorithm.

Compared with the prior art, the present invention has significant advantages in hardware resource consumption, and achieves a better balance in security and implementation performance. In the nonlinear layer, the S-box used has less hardware resource consumption than 8-bit S-boxes of the same type or even some 4-bit S-boxes. Each S-box replacement operation needs to consume 1 NOT gate and 2 AND gates. And 4 XOR gates, a total of about 1×0.5+2×1.3+4×2.65=13.7 standard gate circuits (GE). In contrast, the 4-bit S-box used by the existing popular lightweight block cipher algorithm PRESENT-80 consumes about 28 standard gate circuits. When the block length is 64 bits, the PRESENT round needs to use 16 A total of 28×16=448 GE is occupied by each S box, and only 8 S boxes are used for one round of the Tenon of the present invention, which occupies 13.7×8=109.6 GE. In addition, the linear layer used in this algorithm is bit-level wire replacement, which does not require redundant hardware resources to implement.

In terms of security, the S-box used in the algorithm also has good cryptographic properties, with a differential uniformity of 8, a non-linearity of 96, and an algebraic degree of 7. The 8-bit S-box used is better than the 4-bit wide S-box. The S box has a stronger ability to resist attacks. In the linear layer, the bit-slice technology is applied, so that the bits output by the same S box enter different S boxes in the next round of encryption, and the bits input in the same S box in the next round come from different S boxes in the previous round. output of the box. If the S-box is regarded as a bijective function without considering the specific input-output correspondence, MILP (mixed integer linear programming) is used to find that the minimum number of active S-boxes is 44 under 30 rounds, and the security is not weaker than that of PRESENT. -80 for the result of the algorithm.

The above-mentioned specific implementation can be partially adjusted by those skilled in the art in different ways without departing from the principle and purpose of the present invention. The protection scope of the present invention is based on the claims and is not limited by the above-mentioned specific implementation. Each implementation within the scope is bound by the present invention.

Claims (8)

1. An encryption method based on a lightweight block cipher tenon type algorithm is characterized in that data to be encrypted are divided into equal-length plaintext blocks P according to block length, each block of n bits is divided into equal-length plaintext blocks P, a master key K is set, and the length of the master key K is m₁Bits, round keys of the Tenon block cipher algorithm generated by the key arrangement algorithm from the master key K

1≤r≤30, length m₂Bit, m₁＝128，m₂And 64, in the encryption process, carrying out R rounds of iterative encryption operation on the input data to be encrypted, and outputting an n-bit ciphertext block C.

2. The encryption method based on the lightweight block cipher tenon algorithm as claimed in claim 1, which specifically comprises:

step 1), dividing data to be encrypted into plaintext blocks P with equal length according to the block length, wherein each block of n bits is 64;

step 2) setting a master key K with the length of m₁Bits, round keys of the Tenon block cipher algorithm generated by the key arrangement algorithm from the master key K

R is more than or equal to 1 and less than or equal to 30, and the length is m₂Bit, m₁＝128，m₂64, specifically: for the r round key, the first of 128 bit master key

Bit-sequentially assigning to 64-bit length round key

As for round 1, bits 1,2,4,7, …,97 of the master key are sequentially assigned to bits 0,1,2, …,63 of the round key; then will be

Divided into 4 groups in sequence according to 16 bit length

For the round number r, it is represented as a 5-bit binary number, with the rightmost bit being the lower bit: as 01011 for a wheel number r ═ 11; then, carrying out: 1. the 15 th, 16 th, 31 th, 47 th, 63 th bit in the round key is ANDed with the five bits of the binary representation of r in sequence, and the result is updated to a new k₁₅,k₁₆,k₃₁,k₄₇,k₆₃(ii) a 2. Will be provided with

Is inverted bit by bit to obtain a new k₃₂k₃₃…k₄₇(ii) a 3. Will k₄₈k₄₉…k₆₃And k is₃₂k₃₃…k₄₇After bitwise AND operation, then K is ANDed₀k₁…k₁₅Carrying out XOR operation according to bit to obtain new k₄₈k₄₉…k₆₃(ii) a 64 bits k after update completion₀k₁…k₆₃Divided into 4 groups according to 16 bit length

I.e. the round key of the r-th round, and updates the master key to 128 bits

Step 3) in the encryption process, carrying out R-round iterative encryption operation on the input data to be encrypted, and outputting a ciphertext, specifically:

3.1) for round R1, 2,3, …,29, in each round of encryption: n-bit plaintext blocks P and m₂Round key K for ith round of bits_iAfter round key addition is carried out, the round key is divided into 8 bytes with 8 bits, the bytes are sequentially replaced by a nonlinear layer S box, and after linear layer replacement, output data is used as the input of the next round;

the positive integer n is 64; m is₁＝128；m₂＝64；R＝30；

3.2) for R ═ 30 rounds, n bits are grouped into P and m₂Round key K for ith round of bits_iAnd after round key addition, dividing the round key into 8-bit bytes, and directly outputting a final 64-bit ciphertext block C through nonlinear layer S box replacement.

3. The encryption method based on lightweight block cipher tenon algorithm of claim 2, wherein said roundThe key plus implementation is as follows: the 64-bit plaintext block P for each round of input is represented as P from high order to low order₀，P₁，P₂，...，P₆₂，P₆₃}, round r 64-bit round key

From high to low, denoted by k₀，k₁，k₂，k₃，...，k₆₁，k₆₂，k₆₃Get P out of place_iAnd k is_i(i is 0. ltoreq. i.ltoreq.63) is XOR-ed to obtain a new plaintext block P ═ P₀，P₁，P₂，...，P₆₂，P₆₃}。

4. The encryption method based on the lightweight block cipher tenon algorithm of claim 2, wherein the non-linear layer S-box replacement is implemented as follows: the plaintext P after the round key addition is set as { P }₀，P₁，P₂，...，P₆₂，P₆₃Divide the high order to the low order into a group according to every 8 bits, get 8 byte groups of 8 bits, mark as W₀，W₁，W₂，W₃，W₄，W₅，W₆，W₇Wherein W is_i＝{w_8i+0，w_8i+1，w_8i+2，w_8i+3，w_8i+4，w_8i+5，w_8i+6，w_8i+7I is more than or equal to 0 and less than or equal to 7, and W is₀，W₁，W₂，W₃，W₄，W₅，W₆，W₇Simultaneously through 8 juxtaposed S boxes, the concrete process is to take eight same 8-bit input 8-bit output S box conversion, the conversion is to convert W_iObtaining a new 8-bit output W 'through S-box calculation as an 8-bit input'_i＝{w′_8i+0，w′_8i+1，...，w′_8i+6，w′_8i+7}＝S(W_i)＝S({w_8i+0，w_8i+1，...，w_8i+6，w_8i+7}) the present Tenon algorithm S-box is based on an 8-stage NFSR (non-linear NFSR)Feedback shift register), one S-box operation needs to iterate for 11 beats, the output of the previous beat is used as the input of the next beat, and the input of the sixth bit is used as the first bit of the output in each beat; after inverting the input third bit, carrying out AND operation on the inverted input third bit and the eighth bit, and then respectively carrying out XOR operation on the inverted input third bit and the eighth bit and the fifth bit and the sixth bit to obtain an output second bit; the second bit of the input is used as the third bit of the output; the eighth bit is input as the fourth bit of the output; the sixth bit is input as the seventh bit of the output; the fourth bit is input as the sixth bit of the output; the third bit of the input is used as the seventh bit of the output; the sixth bit and the eighth bit are input and then are subjected to AND operation, and then are subjected to exclusive OR operation with the first bit and the fifth bit respectively to obtain an eighth bit of output, and the 8 juxtaposed S boxes are subjected to the 11-beat operation respectively and then are output as W'₀，W′₁，W′₂，W′₃，W′₄，W′₅，W′₆，W′₇From high to low, into 64 bits C ═ C₀，C₁，C₂，...，C₆₂，C₆₃}。

5. The encryption method based on the lightweight block cipher tenon algorithm of claim 2, wherein the linear layer permutation specifically comprises: performing bit-level wire-drawing replacement on 64 bits subjected to nonlinear layer S-box replacement operation, wherein the specific process is that the 64 bits replace the output 8 bits to a new position according to the sequence of 8S-boxes: w_i8-bit output W 'obtained after S-box replacement'_I＝{w′_8i+0，w′_8i+1，w′_8i+2，w′_8i+3，w′_8i+4，w′_8i+5，w′_8i+6，w′_8i+7Is transformed into { C_{[8(iI1)]mod64+(2i+1)mod8}，C_{[8(iI2)]mod64+(2i+2)mod8}，C_{[8(iI3)]mod64+(2i+3)mod8}，C_{[8(iI4)]mod64+(2i+4)mod8}，

C_{[8(i+5)]mod64+(2i+5)mod8}，C_{[8(i+6)]mod64+(2i+6)mod8}，C_{[8(i+7)]mod64+(2i+7)mod8}，C_{[8(i+8)]mod64+(2i+8)mod8}I is more than or equal to 0 and less than or equal to 7.

6. A decryption method according to any one of claims 1 to 5, comprising: the key orchestration algorithm generates round keys, nonlinear layer inverse S-box substitution, round key addition, and linear layer inverse permutation.

7. The decryption method according to claim 6, wherein the key arrangement algorithm comprises: the nonlinear layer inverse S box replacement is to divide 64-bit ciphertext blocks C into 8 groups according to the 8-bit width, and the ith group is marked as W'_i＝{w′_8i+0，w′_8i+1，w′_8i+2，w′_8i+3，w′_8i+4，w′_8i+5，w′_8i+6，w′_8i+7H, i is more than or equal to 0 and less than or equal to 7, and W'_iW is obtained by inverse S box substitution_iWherein the selected inverse S-box is described in the detailed description; the round key adding operation is the same as the round key adding operation in the step 3.1; the linear layer inverse transform is to group the ciphertext into group C_{[8(i+1)]mod64+(2i+1)mod8}，C_{[8(i+2)]mod64+(2i+2)mod8}，C_{[8(i+3)]mod64+(2i+3)mod8}，C_{[8(i+4)]mod64+(2i+4)mod8}，C_{[8(i+5)]mod64+(2i+5)mod8}，C_{[8(i+6)]mod64+(2i+6)mod8}，C_{[8(i+7)]mod64+(2i+7)mod8}，C_{[8(i+8)]mod64+(2i+8)mod8}Is converted to W'_i＝{w′_8i+0，w′_8i+1，w′_8i+2，w′_8i+3，w′_8i+4，w′_8i+5，w′_8i+6，w′_8i+7This is the opposite of the bracing wire replacement chosen in the encryption process.

8. The decryption method according to claim 7, wherein for R-30, only the ciphertext block C needs to be subjected to the inverse S-box substitution and round key plus two operations; for R is more than or equal to 1 and less than or equal to 29, the decryption process needs to sequentially perform linear layer inverse replacement, inverse S box replacement and round key plus three times of operation, and finally correct plaintext subdivision P is obtained.

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