CN105376046B - A kind of encipher-decipher method and device of block cipher attack protection - Google Patents

Abstract

The invention discloses a block cipher attack-proof encryption and decryption method and device, wherein the encryption method includes: receiving plaintext P to be encrypted, performing two normal encryption operations on the plaintext P, and outputting a correct encryption result; During the encryption operation, the normal encryption operation process is injected with a fault once or twice, and the wrong encryption result is output; after the correct encryption result and the wrong encryption result are input into the F function, an invalid result that cannot be used by the attacker is output. In the embodiment of the present invention, faults are injected during the first and/or second normal encryption operations, and the encrypted results output twice are input into the F function, reducing the steps of comparing the results of the two normal encryption operations, Finally, the F function outputs an invalid result that the attacker cannot use, which effectively resists the double-point attack on the block cipher algorithm and improves the security of the encryption process of the block cipher algorithm.

Description

Encryption and decryption method and device for block cipher attack prevention

technical field

The present invention relates to the technical field of information security in the field of communication, in particular to a method and device for encryption and decryption of block ciphers against attacks.

Background technique

With the development of computer and communication technology, users have increasingly strong demands for safe storage, safe processing and safe transmission of information. Especially, with the wide application of the Internet, the issue of information security becomes more and more important. One of the effective means to solve the above problems is to use modern cryptographic techniques, and various cryptographic algorithms continue to emerge. The block cipher algorithm is one of the most commonly used encryption methods. The block cipher algorithm has the characteristics of fast speed, easy standardization, and easy hardware and software implementation. It is usually the core cryptographic algorithm for data encryption, message authentication, and authentication in information security. Currently, popular block cipher algorithms include DES algorithm, AES algorithm and so on.

With the increasing attention of people on the issue of information security, various methods of analyzing and attacking cryptographic algorithms are constantly appearing. Fault attack is a powerful attack method that has emerged in recent years. Its basic principle is to place the encryption chip in a strong magnetic field, or change the power supply voltage, operating frequency, temperature, etc. of the chip, so that the registers and memories in the encryption chip will generate random errors during the encryption and decryption process, and some output bits will change from the original 0's become 1's or 1's become 0's. By comparing the difference between the correct password output and the wrong password output, and through theoretical analysis, the password data information inside the chip can be obtained.

The common anti-failure attack methods of block ciphers include: perform multiple operations on the same data, and compare whether the results of multiple operations are consistent; after performing normal operations on a certain data, perform inverse operations on the operation results, and compare the inverse operation results with the original input Are the data consistent.

As shown in Figure 1, if the attacker injects a fault during the first normal operation on plaintext P, the output result C of the first normal operation is an incorrect result, and the second normal operation on plaintext P The output result C' is the correct result, at this time C≠C'; then compare the result C with the result C', that is, determine whether C and C' are equal, and inject the fault again when the result is compared, due to the fault Injection, there is the possibility of attacking "C≠C'" into "C=C'". If the injection fault attacks "C≠C'" into "C=C'", the comparison result is output as an error result C (or C'). The attacker obtains the wrong result C (or C'), plus the correct result C' obtained before, and can obtain useful fault information, thereby obtaining sensitive information.

Similarly, if the attacker does not inject a fault during the first normal operation on the plaintext P, and injects a fault when performing the second normal operation on the plaintext P, similar to the above situation, the attacker can still obtain the wrong result C'( or C), plus another correct result C that has been obtained before, can obtain useful fault information, thereby obtaining sensitive information.

Contents of the invention

The purpose of the present invention is to overcome the defect of low security of the block cipher in the prior art when preventing attacks. According to one aspect of the present invention, an encryption method for block cipher attack prevention is proposed.

The block cipher attack-proof encryption method according to an embodiment of the present invention includes:

Receive the plaintext P to be encrypted, perform two normal encryption operations on the plaintext P, and output the correct encryption result;

During the normal encryption operation, the normal encryption operation process is injected with a fault once or twice, and the wrong encryption result is output;

After the correct encryption result and the wrong encryption result are input into the F function, an invalid result that cannot be exploited by the attacker is output.

The purpose of the present invention is to overcome the defect that block ciphers in the prior art have low security when preventing attacks. According to another aspect of the present invention, an encryption device for block ciphers against attacks is proposed.

The block cipher attack-proof encryption device according to an embodiment of the present invention includes:

The encryption operation module is used to receive the plaintext P to be encrypted, perform two normal encryption operations on the plaintext P, and output the correct encryption result;

The fault receiving module is used for receiving the fault injected once or twice during the normal encryption operation process, and outputting the wrong encryption result;

The result output module is used for outputting invalid results that cannot be used by attackers after the correct encrypted results and wrong encrypted results are input into the F function.

The embodiment of the present invention discloses a block cipher attack-proof encryption method and device, in which a fault is injected during the first and/or second normal encryption operation, and the encryption result output by the first normal encryption operation is compared with the The encryption result output by the second normal encryption operation is input into the F function, which reduces the steps of comparing the results of the two normal encryption operations, and finally the F function outputs an invalid result that the attacker cannot use, effectively resisting the block cipher The double-point attack of the algorithm improves the security of the encryption process of the block cipher algorithm.

The purpose of the present invention is to overcome the defect that block ciphers in the prior art have low security when preventing attacks, and according to one aspect of the present invention, a decryption method for block ciphers against attacks is proposed.

The block cipher attack-proof decryption method according to an embodiment of the present invention includes:

Receive the ciphertext P to be decrypted, perform two normal decryption operations on the ciphertext P, and output the correct decryption result;

During the normal decryption operation, the normal encryption operation process is injected with a fault once or twice, and the wrong decryption result is output;

After the correct decryption result and the wrong decryption result are input into the F function, an invalid result that cannot be exploited by the attacker is output.

The purpose of the present invention is to overcome the defect of low security of block cipher in the prior art when preventing attacks. According to one aspect of the present invention, a decryption device for block cipher attack prevention is proposed.

The block cipher attack-proof decryption device according to an embodiment of the present invention includes:

The decryption operation module is used to receive the ciphertext P to be decrypted, perform two normal decryption operations on the ciphertext P, and output the correct decryption result;

The fault receiving module is used to receive the fault injected once or twice during the normal encryption operation process during the normal decryption operation, and output the wrong decryption result;

The result output module is used for outputting an invalid result that an attacker cannot utilize after the correct decryption result and the wrong decryption result are input into the F function.

The embodiment of the present invention discloses a block cipher attack-proof decryption method and device, which injects a fault when performing the first and/or second normal decryption operations, and compares the decryption result output by the first normal decryption operation with the The decryption result output by the second normal decryption operation is input into the F function, which reduces the steps of comparing the results of the two normal decryption operations, and finally the F function outputs an invalid result that the attacker cannot use, effectively resisting the block cipher The double-point attack of the algorithm improves the security of the decryption process of the block cipher algorithm.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

The technical solutions of the present invention will be described in further detail below with reference to the accompanying drawings and embodiments.

Description of drawings

The accompanying drawings are used to provide a further understanding of the present invention, and constitute a part of the description, and are used together with the embodiments of the present invention to explain the present invention, and do not constitute a limitation to the present invention. In the attached picture:

FIG. 1 is a flow diagram of a fault attack on a block cipher in the prior art;

Fig. 2 is the flow chart of Embodiment 1 of the encryption method of block cipher attack prevention of the present invention;

Fig. 3 is the flow chart of Embodiment 2 of the encryption method of block cipher attack prevention of the present invention;

Fig. 4 is the flow chart of embodiment 3 of the encryption method of block cipher attack prevention of the present invention;

Fig. 5 is the flow chart of Embodiment 4 of the encryption method for block cipher attack prevention of the present invention;

Fig. 6 is the flow chart of Embodiment 1 of the decryption method for block cipher attack prevention of the present invention;

FIG. 7 is a flow chart of Embodiment 2 of the decryption method for block cipher attack prevention in the present invention;

FIG. 8 is a flow chart of Embodiment 3 of the decryption method for block cipher attack prevention in the present invention;

FIG. 9 is a flow chart of Embodiment 4 of the decryption method for block cipher attack prevention in the present invention;

FIG. 10 is a structural diagram of an embodiment of an encryption device for block cipher attack prevention according to the present invention;

FIG. 11 is a structural diagram of an embodiment of a block cipher attack-proof decryption device according to the present invention.

Detailed ways

The specific embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, but it should be understood that the protection scope of the present invention is not limited by the specific embodiments.

The inventors of the present invention found in the analysis and research of the above-mentioned prior art that if a fault injection is detected during the operation of the block cipher algorithm for encryption or decryption, the chip should not output wrong calculation results, otherwise the attacker can use Differential fault attacks are performed on wrong operation results. The embodiment of the present invention provides a block cipher attack prevention method. When there is a fault injection in the operation process, the wrong operation result is not output, but an invalid result that cannot be used by the attacker is output.

If the first normal operation is not injected into the fault, the second normal operation is injected into the fault, the invalid result is the correct first normal operation result C and the wrong second normal operation result C' processed by a certain F function The result of the subsequent operation.

If the first normal operation is injected with a fault and the second normal operation is not injected with a fault, the invalid result is the wrong first normal operation result C and the correct second normal operation result C' processed by a certain F function The result of the subsequent operation.

If the first normal operation is injected with a fault, the second normal operation is also injected with a fault, the invalid result is the wrong first normal operation result C and the wrong second normal operation result C' processed by a certain F function The result of the subsequent operation.

As shown in Figure 2, the embodiment of the present invention discloses a block cipher anti-attack encryption method, including:

Step 201: Input the plaintext P into the encryption module to perform the first normal encryption operation. At the same time, this step is injected with a fault, so the output is the wrong encryption result C;

Step 203: Input the same plaintext P into the encryption module again, perform the second normal encryption operation, and output the correct encryption result C';

Step 205: Input the wrong encryption result C in step 201 and the correct encryption result C' in step 203 into the F function, and the output of this function is Y; the F function knows through judgment that C≠C', so the output operation result is Invalid results that cannot be exploited by attackers;

For different grouping algorithms, the expression of the F function is different. This specification uses the following expressions to describe the embodiment, but the expression of the F function should not be limited to the following expressions.

Taking the DES algorithm as an example, the encryption result C is composed of L and R, and the encryption result C' is composed of L' and R', that is, C=L||R, C'=L'||R', then The F function can be defined as:

In step 205, the F function may or may not be injected with a fault. Due to the existence of the above-mentioned F-function, no matter whether a fault is injected or not, the calculation result output by the above-mentioned F-function is an invalid result that cannot be used by an attacker.

Step 207: Perform an encryption operation on the plaintext P, and output an invalid result Y that cannot be exploited by an attacker.

The embodiment in Fig. 2 discloses a block cipher anti-attack encryption method, a fault is injected during the first normal encryption operation, and the wrong encryption result output by the first normal encryption operation injected with the fault is compared with the second The correct encryption result output by the normal encryption operation is input into the F function, which reduces the steps of comparing the results of the two normal encryption operations, and finally the F function outputs an invalid result that the attacker cannot use, effectively resisting the attack on the block cipher algorithm Double-point attack improves the security of the encryption process of the block cipher algorithm.

As shown in Figure 3, the embodiment of the present invention discloses another block cipher anti-attack encryption method, including:

Step 301: Input the plaintext P into the encryption module, perform the first normal encryption operation, and output the correct encryption result C;

Step 303: The same plaintext P is input into the encryption module again, and the second normal encryption operation is performed. At the same time, this step is injected with a fault, so the output is the wrong encryption result C';

Step 305: Input the correct encryption result C in step 301 and the wrong encryption result C' in step 303 into the F function, and the output of this function is Y; the F function knows through judgment that C≠C', so the output operation result is Invalid results that cannot be exploited by attackers;

For different grouping algorithms, the expression of F function is different.

Taking the DES algorithm as an example, the encryption result C is composed of L and R, and the encryption result C' is composed of L' and R', that is, C=L||R, C'=L'||R', then The F function can be defined as:

In step 305, the F-function may or may not be injected with a fault. Due to the existence of the above-mentioned F-function, no matter whether a fault is injected or not, the calculation result output by the above-mentioned F-function is an invalid result that cannot be used by an attacker.

Step 307: Perform an encryption operation on the plaintext P, and output an invalid result Y that cannot be exploited by an attacker.

The embodiment in Fig. 3 discloses a block cipher anti-attack encryption method, a fault is injected during the second normal encryption operation, and the wrong encryption result output by the second normal encryption operation injected with the fault is the same as the first The correct encryption result output by the normal encryption operation is input into the F function, which reduces the steps of comparing the results of the two normal encryption operations, and finally the F function outputs an invalid result that the attacker cannot use, effectively resisting the attack on the block cipher algorithm Double-point attack improves the security of the encryption process of the block cipher algorithm.

As shown in Figure 4, the embodiment of the present invention discloses a third block cipher attack-proof encryption method, including:

Step 401: Input the plaintext P into the encryption module to perform the first normal encryption operation. At the same time, this step is injected with a fault, so the output is the wrong encryption result C;

Step 403: Input the same plaintext P into the encryption module again to perform the second normal encryption operation. At the same time, this step is injected with a fault, so the output is also the wrong encryption result C';

Step 405: Input the wrong encryption result C in step 401 and the wrong encryption result C' in step 403 into the F function, and the output of this function is Y; the F function knows through judgment that C≠C', so the output operation result is Invalid results that cannot be exploited by attackers;

For different grouping algorithms, the expression of F function is different.

Taking the DES algorithm as an example, the encryption result C is composed of L and R, and the encryption result C' is composed of L' and R', that is, C=L||R, C'=L'||R', then The F function can be defined as:

In step 405, the F-function may or may not be injected with a fault. Due to the existence of the above-mentioned F-function, no matter whether a fault is injected or not, the calculation result output by the above-mentioned F-function is an invalid result that cannot be used by an attacker.

Step 407: Perform an encryption operation on the plaintext P, and output an invalid result Y that cannot be exploited by an attacker.

The embodiment in Fig. 4 discloses a third block cipher attack-proof encryption method, in which a fault is injected during the first and second normal encryption operations, and the error output by the first normal encryption operation injected with the fault is output The encryption result and the wrong encryption result output by the second normal encryption operation that is also injected into the fault are input into the F function, which reduces the steps of comparing the results of the two normal encryption operations, and finally the F function outputs an invalid value that the attacker cannot exploit. As a result, the two-point attack on the block cipher algorithm is effectively resisted, and the security of the encryption process of the block cipher algorithm is improved.

As shown in Figure 5, the embodiment of the present invention discloses a fourth block cipher attack-proof encryption method, including:

Step 501: Input the plaintext P into the encryption module, perform the first normal encryption operation, and output the correct encryption result C;

Step 503: The same plaintext P is input into the encryption module again, and the second normal encryption operation is performed, and the output is also the correct encryption result C';

Step 505: Input the correct encryption result C in step 501 and the correct encryption result C' in step 503 into the F function, and the output of this function is Y; the F function knows through judgment that C=C', so the output operation result is The correct encryption operation result;

In step 505, the F-function may or may not be injected with a fault. If the F function is not injected with a fault, the calculation result output by the F function is a correct encrypted calculation result. If the F function is injected with a fault, as in the above embodiment, the F function will also output an invalid result that cannot be used by an attacker.

Step 507: Perform an encryption operation on the plaintext P, and output a correct encryption operation result.

The embodiment in Fig. 5 discloses a block cipher anti-attack encryption method, no fault is injected during two normal encryption operations, and the correct encryption results of the two normal encryption operations are input into the F function, and the F function The output of the correct encryption operation result effectively resists the double-point attack on the block cipher algorithm and improves the security of the encryption process of the block cipher algorithm.

As shown in Figure 6, the embodiment of the present invention discloses a block cipher anti-attack decryption method, including:

Step 601: The ciphertext P is input into the decryption module, and the first normal decryption operation is performed. At the same time, this step is injected with a fault, so the output is the wrong decryption result C;

Step 603: The same ciphertext P is input into the decryption module again, and the second normal decryption operation is performed, and the output is the correct decryption result C';

Step 605: Input the wrong decryption result C in step 601 and the correct decryption result C' in step 603 into the F function, and the output of this function is Y; the F function knows through judgment that C≠C', so the output operation result is Invalid results that cannot be exploited by attackers;

For different grouping algorithms, the expression of the F function is different. This specification uses the following expressions to describe the embodiment, but the expression of the F function should not be limited to the following expressions.

Taking the DES algorithm as an example, the decryption result C is composed of L and R, and the decryption result C' is composed of L' and R', that is, C=L||R, C'=L'||R', then The F function can be defined as:

In step 605, the F-function may or may not be injected with a fault. Due to the existence of the above-mentioned F-function, no matter whether a fault is injected or not, the calculation result output by the above-mentioned F-function is an invalid result that cannot be used by an attacker.

Step 607: Perform a decryption operation on the ciphertext P, and output an invalid result Y that cannot be exploited by an attacker.

The embodiment in Fig. 6 discloses a block cipher anti-attack decryption method, a fault is injected during the first normal decryption operation, and the wrong decryption result output by the first normal decryption operation injected with the fault is compared with the second The correct decryption result output by the normal decryption operation is input into the F function, which reduces the steps of comparing the results of the two normal decryption operations, and finally the F function outputs an invalid result that the attacker cannot use, effectively resisting the attack on the block cipher algorithm Double-point attack improves the security of the block cipher algorithm decryption process.

As shown in Figure 7, the embodiment of the present invention discloses another block cipher anti-attack decryption method, including:

Step 701: Input the ciphertext P into the decryption module, perform the first normal decryption operation, and output the correct decryption result C;

Step 703: The same ciphertext P is input into the decryption module again, and the second normal decryption operation is performed. At the same time, this step is injected with a fault, so the output is the wrong decryption result C';

Step 705: Input the correct decryption result C in step 701 and the wrong decryption result C' in step 703 into the F function, and the output of this function is Y; the F function knows through judgment that C≠C', so the output operation result is Invalid results that cannot be exploited by attackers;

For different grouping algorithms, the expression of the F function is different. This specification uses the following expressions to describe the embodiment, but the expression of the F function should not be limited to the following expressions.

Taking the DES algorithm as an example, the decryption result C is composed of L and R, and the decryption result C' is composed of L' and R', that is, C=L||R, C'=L'||R', then The F function can be defined as:

In step 705, the F-function may or may not be injected with a fault. Due to the existence of the above-mentioned F-function, no matter whether a fault is injected or not, the calculation result output by the above-mentioned F-function is an invalid result that cannot be used by an attacker.

Step 707: Perform a decryption operation on the ciphertext P, and output an invalid result Y that cannot be exploited by an attacker.

The embodiment in Fig. 7 discloses a block cipher anti-attack decryption method, a fault is injected during the second normal decryption operation, and the wrong decryption result output by the second normal decryption operation injected with the fault is the same as the first The correct decryption result output by the normal decryption operation is input into the F function, which reduces the steps of comparing the results of the two normal decryption operations, and finally the F function outputs an invalid result that the attacker cannot use, effectively resisting the attack on the block cipher algorithm Double-point attack improves the security of the block cipher algorithm decryption process.

As shown in Figure 8, the embodiment of the present invention discloses a third block cipher attack prevention decryption method, including:

Step 801: The ciphertext P is input into the decryption module, and the first normal decryption operation is performed. At the same time, this step is injected with a fault, so the output is the wrong decryption result C;

Step 803: The same ciphertext P is input into the decryption module again, and the second normal decryption operation is performed. At the same time, this step is injected with a fault, so the output is the wrong decryption result C';

Step 805: Input the wrong decryption result C in step 801 and the wrong decryption result C' in step 803 into the F function, and the output of this function is Y; the F function knows through judgment that C≠C', so the output operation result is Invalid results that cannot be exploited by attackers;

For different grouping algorithms, the expression of the F function is different. This specification uses the following expressions to describe the embodiment, but the expression of the F function should not be limited to the following expressions.

Taking the DES algorithm as an example, the decryption result C is composed of L and R, and the decryption result C' is composed of L' and R', that is, C=L||R, C'=L'||R', then The F function can be defined as:

In step 805, the F-function may or may not be injected with a fault. Due to the existence of the above-mentioned F-function, no matter whether a fault is injected or not, the calculation result output by the above-mentioned F-function is an invalid result that cannot be used by an attacker.

Step 807: Perform a decryption operation on the plaintext P, and output an invalid result Y that cannot be exploited by an attacker.

The embodiment in Figure 8 discloses the third block cipher anti-attack decryption method, which injects faults when performing the first and second normal decryption operations, and outputs errors from the first normal decryption operation that is injected with faults The decryption result and the wrong decryption result output by the second normal decryption operation that is also injected into the fault are input into the F function, which reduces the steps of comparing the results of the two normal decryption operations, and finally the F function outputs an invalid value that the attacker cannot exploit. As a result, the two-point attack on the block cipher algorithm is effectively resisted, and the security of the decryption process of the block cipher algorithm is improved.

As shown in Figure 9, the embodiment of the present invention discloses a fourth block cipher attack prevention decryption method, including:

Step 901: input the ciphertext P into the decryption module, perform the first normal decryption operation, and output the correct decryption result C;

Step 903: The same ciphertext P is input into the decryption module again, and the normal decryption operation is performed for the second time, and the output is also the correct decryption result C';

Step 905: Input the correct decryption result C in step 901 and the correct decryption result C' in step 903 into the F function, and the output of this function is Y; the F function knows through judgment that C=C', so the output operation result is The correct decryption operation result;

For different grouping algorithms, the expression of the F function is different. This specification uses the following expressions to describe the embodiment, but the expression of the F function should not be limited to the following expressions.

Taking the DES algorithm as an example, the decryption result C is composed of L and R, and the decryption result C' is composed of L' and R', that is, C=L||R, C'=L'||R', then The F function can be defined as:

In step 905, the F function may or may not be injected with a fault. If the F function is not injected with a fault, the calculation result output by the F function is a correct encrypted calculation result. If the F function is injected with a fault, as in the above embodiment, the F function will also output an invalid result that cannot be used by an attacker.

Step 907: Perform a decryption operation on the ciphertext P, and output a correct decryption operation result.

The embodiment in Fig. 9 discloses a block cipher anti-attack decryption method, no fault is injected during two normal decryption operations, and the correct decryption results of the two normal decryption operations are input into the F function, and the F function The correct decryption operation result is output, effectively resisting the double-point attack on the block cipher algorithm, and improving the security of the decryption process of the block cipher algorithm.

As shown in Figure 10, an encryption device for block cipher attack prevention is disclosed, including:

The encryption operation module 10 is used to receive the plaintext P to be encrypted, perform two normal encryption operations on the plaintext P, and output the correct encryption result;

The fault receiving module 20 is used to receive the fault injected once or twice during the normal encryption operation process, and output the wrong encryption result;

The result output module 30 is used for outputting an invalid result that cannot be used by an attacker after the correct encryption result and the wrong encryption result are input into the F function.

Wherein: the failure receiving module 20 is specifically used to receive the injected failure of this normal encryption operation when performing the first normal encryption operation on the plaintext P, and output an error encryption result;

When the second normal encryption operation is performed on the plaintext P, the correct encryption result is output.

Wherein: the failure receiving module 20 is specifically also used for outputting a correct encryption result when performing the first normal encryption operation on the plaintext P;

When the second normal encryption operation is performed on the plaintext P, the fault injected into this normal encryption operation is received, and an erroneous encryption result is output.

Wherein: the fault receiving module 20 is also specifically used for,

When the first normal encryption operation is performed on the plaintext P, the fault injected into this normal encryption operation is received, and the wrong encryption result is output;

When the second normal encryption operation is performed on the plaintext P, the fault injected into this normal encryption operation is received, and an erroneous encryption result is output.

The embodiment of Fig. 10 discloses a block cipher attack-proof encryption device, which is injected with a fault when performing the first and/or second normal encryption operation, and compares the encryption result output by the first normal encryption operation with the second The encryption result output by the second normal encryption operation is input into the F function, which reduces the steps of comparing the results of the two normal encryption operations, and finally the F function outputs an invalid result that the attacker cannot use, effectively resisting the attack on the block cipher algorithm Double-point attack improves the security of the encryption process of the block cipher algorithm.

As shown in Figure 11, a decryption device for block cipher attack prevention is disclosed, including:

The decryption operation module 40 is used to receive the ciphertext P to be decrypted, perform two normal decryption operations on the ciphertext P, and output the correct decryption result;

The fault receiving module 50 is used for receiving the fault injected once or twice during the normal decryption operation, and outputting the wrong decryption result;

The result output module 60 is used for outputting an invalid result that cannot be used by an attacker after the correct decryption result and the wrong decryption result are input into the F function.

Wherein: the failure receiving module 50 is specifically used to receive the injected failure of this normal decryption operation when performing the first normal decryption operation on the ciphertext P, and output an error decryption result;

When the second normal decryption operation is performed on the ciphertext P, the correct decryption result is output.

Wherein: the failure receiving module 50 is specifically also used for outputting a correct decryption result when the first normal decryption operation is performed on the ciphertext P;

When the second normal decryption operation is performed on the ciphertext P, the fault injected into this normal decryption operation is received, and an error decryption result is output.

Wherein: the fault receiving module 50 is specifically also used for receiving the fault injected into the normal decryption operation during the first normal decryption operation on the ciphertext P, and outputting an error decryption result;

When the second normal decryption operation is performed on the ciphertext P, the fault injected into this normal decryption operation is received, and an error decryption result is output.

The embodiment in Fig. 11 discloses a block cipher anti-attack decryption device, which is injected with a fault when performing the first and/or second normal decryption operation, and compares the decryption result output by the first normal decryption operation with the second The decryption result output by the second normal decryption operation is input into the F function, which reduces the steps of comparing the results of the two normal decryption operations, and finally the F function outputs an invalid result that the attacker cannot use, effectively resisting the attack on the block cipher algorithm Double-point attack improves the security of the block cipher algorithm decryption process.

The present invention can have multiple specific implementations in different forms. The technical solution of the present invention is illustrated by taking Fig. 2-Fig. 11 as an example in conjunction with the accompanying drawings. In the specific process or embodiment structure, those skilled in the art should understand that the specific implementations provided above are only some examples of various preferred usages, and any implementation that embodies the claims of the present invention shall be included in the present invention. Within the scope of protection required by the technical solution.

Finally, it should be noted that: the above is only a preferred embodiment of the present invention, and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, it still The technical solutions recorded in the foregoing embodiments may be modified, or some technical features thereof may be equivalently replaced. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (20)

1. An encryption method for block cipher attack prevention, characterized in that, comprising: Receive the plaintext P to be encrypted, perform two normal encryption operations on the plaintext P, and output the correct encryption result; When performing the normal encryption operation, the normal encryption operation process is injected with a fault once or twice, and an incorrect encryption result is output; After the correct encryption result and the wrong encryption result are input into the F function, an invalid result that cannot be exploited by an attacker is output. 2. The method according to claim 1, characterized in that, in the two normal encryption operations, the encryption result of the first normal encryption operation is C, and the encryption result of the second normal encryption operation is C', The C is composed of L and R, the C' is composed of L' and R', that is, C=L||R, C'=L'||R', and the F function is defined as: or or 3. The method according to claim 1 or 2, characterized in that, when the normal encryption operation is performed, the normal encryption operation process is injected with a fault once or twice, and the step of outputting an error encryption result specifically includes: When the first normal encryption operation is performed on the plaintext P, a fault is injected into the normal encryption operation this time, and an incorrect encryption result is output; When the second normal encryption operation is performed on the plaintext P, a correct encryption result is output. 4. The method according to claim 1 or 2, characterized in that, when the normal encryption operation is performed, the normal encryption operation process is injected with a fault once or twice, and the step of outputting an error encryption result specifically further comprises: When the first normal encryption operation is performed on the plaintext P, a correct encryption result is output; When the second normal encryption operation is performed on the plaintext P, a fault is injected into the normal encryption operation this time, and an incorrect encryption result is output. 5. The method according to claim 1 or 2, characterized in that, when the normal encryption operation is performed, the normal encryption operation process is injected with a fault once or twice, and the step of outputting an error encryption result specifically further comprises: When the first normal encryption operation is performed on the plaintext P, a fault is injected into the normal encryption operation this time, and an incorrect encryption result is output; When the second normal encryption operation is performed on the plaintext P, a fault is injected into the normal encryption operation this time, and an incorrect encryption result is output. 6. A decryption method for block cipher attack prevention, characterized in that, comprising: Receive the ciphertext P to be decrypted, perform two normal decryption operations on the ciphertext P, and output the correct decryption result; When performing the normal decryption operation, the normal decryption operation process is injected with a fault once or twice, and an incorrect decryption result is output; After the correct decryption result and the wrong decryption result are input into the F function, an invalid result that cannot be used by an attacker is output. 7. The method according to claim 6, characterized in that, in the two normal decryption operations, the decryption result of the first normal decryption operation is C, and the decryption result of the second normal decryption operation is C', The C is composed of L and R, the C' is composed of L' and R', that is, C=L||R, C'=L'||R', and the F function is defined as: or or 8. The method according to claim 6 or 7, wherein when the normal decryption operation is performed, the normal encryption operation process is injected with a fault once or twice, and the step of outputting an error decryption result specifically includes: When the first normal decryption operation is performed on the ciphertext P, a fault is injected into the normal decryption operation this time, and an incorrect decryption result is output; When the second normal decryption operation is performed on the ciphertext P, a correct decryption result is output. 9. The method according to claim 6 or 7, wherein when the normal decryption operation is performed, the normal encryption operation process is injected with a fault once or twice, and the step of outputting an error decryption result specifically further comprises: When the first normal decryption operation is performed on the ciphertext P, a correct decryption result is output; When the second normal decryption operation is performed on the ciphertext P, a fault is injected into the normal decryption operation this time, and an incorrect decryption result is output. 10. The method according to claim 6 or 7, wherein when the normal decryption operation is performed, the normal encryption operation process is injected with a fault once or twice, and the step of outputting an error decryption result specifically further comprises: When the first normal decryption operation is performed on the ciphertext P, a fault is injected into the normal decryption operation this time, and an incorrect decryption result is output; When the second normal decryption operation is performed on the ciphertext P, a fault is injected into the normal decryption operation this time, and an incorrect decryption result is output. 11. An encryption device for block cipher attack prevention, characterized in that it comprises: An encryption operation module is used to receive the plaintext P to be encrypted, perform two normal encryption operations on the plaintext P, and output a correct encryption result; The fault receiving module is used to receive the fault injected once or twice in the normal encryption operation process when performing the normal encryption operation, and output an error encryption result; The result output module is used for outputting invalid results that cannot be used by attackers after the correct encrypted results and wrong encrypted results are input into the F function. 12. The device according to claim 11, characterized in that, in the two normal encryption operations of the encryption operation module, the encryption result of the first normal encryption operation is C, and the encryption result of the second normal encryption operation is C. is C', the C is composed of two parts L and R, and the C' is composed of two parts L' and R', that is, C=L||R, C'=L'||R', the result The F function in the output module is defined as: or or 13. The device according to claim 11 or 12, wherein the fault receiving module is specifically configured to, when performing the normal encryption operation on the plaintext P for the first time, receive the input code injected into the normal encryption operation this time. Failure, output wrong encryption result; When the second normal encryption operation is performed on the plaintext P, a correct encryption result is output. 14. The device according to claim 11 or 12, wherein the fault receiving module is further configured to output a correct encryption result when performing a normal encryption operation on the plaintext P for the first time; When the second normal encryption operation is performed on the plaintext P, the fault injected into this normal encryption operation is received, and an erroneous encryption result is output. 15. The device according to claim 11 or 12, characterized in that, the fault receiving module is further used for: When performing the normal encryption operation on the plaintext P for the first time, receiving the fault injected into this normal encryption operation, and outputting an error encryption result; When the second normal encryption operation is performed on the plaintext P, the fault injected into this normal encryption operation is received, and an erroneous encryption result is output. 16. A block cipher anti-attack decryption device, characterized in that it comprises: The decryption operation module is used to receive the ciphertext P to be decrypted, perform two normal decryption operations on the ciphertext P, and output the correct decryption result; The fault receiving module is used to receive the fault injected once or twice in the normal decryption operation process when performing the normal decryption operation, and output an error decryption result; The result output module is used for outputting an invalid result that an attacker cannot utilize after the correct decryption result and the wrong decryption result are input into the F function. 17. The device according to claim 16, characterized in that, in the two normal decryption operations of the decryption operation module, the decryption result of the first normal decryption operation is C, and the decryption result of the second normal decryption operation is is C', the C is composed of two parts L and R, and the C' is composed of two parts L' and R', that is, C=L||R, C'=L'||R', the result The F function in the output module is defined as: or or 18. The device according to claim 16 or 17, wherein the fault receiving module is specifically configured to, when the first normal decryption operation is performed on the ciphertext P, receive this normal decryption operation to be injected failure, the wrong decryption result is output; When the second normal decryption operation is performed on the ciphertext P, a correct decryption result is output. 19. The device according to claim 16 or 17, wherein the fault receiving module is further configured to output a correct decryption result when performing a normal decryption operation on the ciphertext P for the first time; When the second normal decryption operation is performed on the ciphertext P, the fault injected into this normal decryption operation is received, and an erroneous decryption result is output. 20. The device according to claim 16 or 17, wherein the fault receiving module is further configured to, when performing a normal decryption operation on the ciphertext P for the first time, receive this normal decryption operation Injected failure, output wrong decryption result; When the second normal decryption operation is performed on the ciphertext P, the fault injected into this normal decryption operation is received, and an erroneous decryption result is output.