CN101847199B - Security authentication method for radio frequency recognition system - Google Patents

Abstract

The invention discloses a security authentication method for a radio frequency recognition system, which comprises the following steps of: searching an authentication key through an initial ID of an identifier; performing identifier authentication and reader authentication, and after the identifier and the reader pass the authentication, generating a key for data communication; and using the communication key in subsequent communication, and updating the authentication key of the identifier in real time by a security authentication flow during next communication. The method improves the security of the RFID system by updating the authentication key of the identifier in real time and transmitting information in an encrypted mode and other means, fully ensures the forward security of the authentication key, makes attackers incapable of calculating a key adopted by the previous communication from the currently acquired key, is suitable for any RFID communication protocol and can improve the key search efficiency.

Description

The safety certifying method that is used for radio-frequency recognition system

Technical field

The invention belongs to the REID field, relate to a kind of safety certifying method of radio-frequency recognition system, relate in particular to a kind of communication protocol and safety certifying method of radio-frequency recognition system.

Background technology

RF identification (RFID) is a kind of automatic identification technology that carries out the noncontact two-way communication through electromagnetic wave.The ultimate system of RF identification comprises electronic tag (hereinafter to be referred as label) and read write line.Twentieth century nineties, the RFID technology begins to be widely used in transportation card, fields such as gate inhibition's card.In recent years, the RFID technology constantly appears at various new applications, commodity counterfeit prevention for example, and E-Passport, car key, the care of animal, taking care of books, supply chain management and Olympic Games ticket etc., even have the people to advise implant into body with RFID.

Undoubtedly, applying of RFID technology makes human life become convenient, but also more and more causes that people are to the safety brought thus and the concern of privacy concern simultaneously.Unsafe rfid system threatens individual privacy except meeting, also can cause the leakage of incorporation's sensitive information.The safety problem of rfid system relates to each links such as background system, middleware, read write line and electronic tag; But; Therefore electronics becomes weak and the easiest link under attack in the rfid system because cost is limit, and the resource that can be used in Safety Design is minimum.The common attack means that face between read write line and the label in the rfid system mainly comprise: physical attacks, forge clone, unauthorized access, eavesdropping, tracking and denial of service etc.International Industry circle and academia have launched research to the safe privacy concern of rfid system; Many solutions have been proposed; Roughly can be divided into two types: one type of safety approach is based on the safety approach of non-cryptographic algorithm; For example, make method and use " blocker " the label assailant etc. of Void Label through " kill " instruction.Adopt non-cryptographic method simple, but security performance is unreliable, can only prevent partly that label from being read arbitrarily to the method that read write line and label carry out authentication.Another kind of safety approach is based on the safety approach of cryptographic algorithm, because label resources is limited, the safety approach that adopts symmetric cryptographic algorithm is the main flow of studying at present.Though existing security solution based on cryptographic algorithm has adopted identifying procedure, do not solve problems such as following the tracks of risk and key lookup.

Summary of the invention

The objective of the invention is deficiency, propose a kind of safety certifying method that is applicable to radio-frequency recognition system, relate in particular to a kind of communication protocol and safety certifying method of radio-frequency recognition system to prior art.The present invention increased authenticate key inquiry and two-way authentication flow process before read write line and label carry out proper communication, the smart-tag authentication key is carried out real-time update, and the data communication after authentication accomplished encrypts, with the security of raising rfid system.The present invention utilizes the characteristic of symmetric key algorithm and one-way function, has protected authenticate key effectively, has guaranteed the forward secrecy of data transmission, is suitable for any RFID communication protocol.

Fundamental purpose of the present invention realizes through following technical scheme: is used for the safety certifying method of RF identification, comprises smart-tag authentication and read write line authentication, comprise that also authenticate key is searched and authenticate key upgrades,

At first, label receives the request access instruction, and label returns the interim ID of encryption, i.e. metaID ⁱ(i=0...n is initial ID during i=0), the metaID of read write line to encrypt ⁱAs the corresponding authenticate key K of index search _Authen ⁱ

Carry out smart-tag authentication and read write line authentication then;

Described smart-tag authentication comprises that label receives the random number R 1 that read write line sends, and label is with the authenticate key K of oneself _Authen ⁱR1 encrypted obtain S1, label sends to read write line with S1, and read write line uses the authenticate key K that finds _Authen ⁱTo the S1 deciphering, if decrypted result is identical with R1, care label is legal; Otherwise label can not be through authentication, sign off;

Label through authentication after, again read write line is carried out authentication, described read write line authentication comprises, label generates random number R 2, utilizes authenticate key K _Authen ⁱEncryption obtains S2, sends to read write line, and read write line is used authenticate key K _Authen ⁱDecrypt random number R 2, obtain ciphertext S3 with R2 as secret key encryption R1 again,, explain that read write line is legal if C2 is identical with S3; If unequal, read write line can not be through authentication, sign off;

Read write line, is encrypted information transmitted the key of R2 as the i data transfer also through after the authentication;

Carry out authenticate key at last and upgrade, read write line generates the authenticate key K of random number R 3 as communication _Authen ^I+1, H calculates metaID with one-way function ^I+1, read write line upgrades the authenticate key and interim ID, i.e. (metaID of this label ^I+1, K _Authen ^I+1), and with (metaID ^I+1, K _Authen ^I+1) write label safely, during the i+1 time communication, with (metaID ^I+1, K _Authen ^I+1) original (metaID of replacement ⁱ, K _Authen ⁱ).

Said interim IDmetaID ⁱWith authenticate key K _Authen ⁱRelation do, ${\mathrm{MetaID}}^i=H\left(K_{\mathrm{Authen}}^i\right),$ Wherein H is an one-way function.

Said with (metaID ^I+1, K _Authen ^I+1) write label safely, comprise that read write line is with metaID ^I+1And K _Authen ^I+1Respectively with R ₂XOR obtains $\mathrm{\α}={\mathrm{MetaID}}^{i+1}\⊕R_2$ With $\mathrm{\γ}=K_{\mathrm{Authen}}^{i+1}\⊕R_2,$ α and β are sent to label; After label receives, with α and β respectively with R ₂XOR promptly can obtain (metaID ^I+1, K _Authen ^I+1), and with (metaID ^I+1, K _Authen ^I+1) original (metaID of replacement ⁱ, K _Authen ⁱ).

After the two-way authentication of label and read write line was all passed through, the data transmission between label and the read write line was all carried out with the ciphertext form, and the encrypted transmission flow process comprises

When read write line during to the tag ram writing information,

Suppose that the information that will write is M ₁, read write line at first utilizes key R ₂It is encrypted, and read write line obtains corresponding ciphertext Cipher1=Enc (M after encrypting ₁, R ₂), Enc representes AES, read write line sends write command write, and (Cipher1 addr1), comprises the ciphertext Cipher1 that writes and writes address addr1 in the instruction; Label receive write command write (Cipher1, addr1) after, utilize key R ₂Deciphering obtains plaintext M to ciphertext Cipher1 ₁=Dec (Cipher1, R ₂), Dec representes decrypt operation, and with M ₁Corresponding address unit in the write store.Behind the label success writing information, return and write response of successful write_success;

Described encrypted transmission flow process also comprises,

When read write line reading tag memorizer information,

Suppose that the information that will read is M ₂, the address is addr2, read write line sends the Read (addr2) that reads instruction; Label is with the information M of address addr2 ₂Use key R ₂Encryption obtains corresponding ciphertext Cipher2=Enc (M ₂, R ₂), Enc is an AES, and it is returned to read write line; Read write line utilizes key R ₂Deciphering obtains plaintext M to ciphertext Cipher2 ₂=Dec (Cipher2, R ₂), the Dec decipherment algorithm.

When read write line writes data to label, also comprise data integrity verifying,

At first, the computing information summary,

The plaintext of supposing transmission information is M ₁, read write line at first utilizes key R ₂It is encrypted, obtain ciphertext Cipher1=Enc (M ₁, R ₂), and with hash function Hash calculating M ₁Corresponding informative abstract Hash (M ₁),

Then, carry out informative abstract relatively,

Read write line sends to label through writing instruction with ciphertext, label to ciphertext Cipher1 decipher obtain corresponding plaintext M ' ₁, calculate then its corresponding Hash (M ' ₁), with Hash (M ₁) and Hash (M ' ₁) relatively, if consistent, then with M ' ₁It writes the storage unit of assigned address, writes response of successful with returning;

Read write line also comprises data integrity verifying during from the label read data,

At first, the computing information summary,

Read write line sends the Read (addr2) that reads instruction, and label reads corresponding cleartext information M according to the address from storer ₂, calculate M with hash function Hash earlier ₂Corresponding informative abstract Hash (M ₂),

Then, carry out the comparison of informative abstract,

To M ₂Encrypt, at last with M ₂Ciphertext Cipher2=Enc (M ₂, R ₂) and summary info Hash (M ₂) send read write line simultaneously to; Read write line at first obtains plaintext M to decrypt ciphertext ₂, calculate its corresponding summary info then, obtain Hash (M ' ₂), if Hash (M ' ₂) with the Hash (M that receives ₂) equate the data M of care label ₂Do not distorted, thereby guaranteed the tag storage information integrity.When label itself has independently HASH function calculation function calculate because label can carry out HASH to any data of memory block, so the time M ₂With M ₁There is not correlativity yet.

The invention has the advantages that, increase the two-way authentication flow process before communicate, real-time update smart-tag authentication key and adopt means such as ciphertext transmission information to realize above-mentioned Security Target through the read write line label; Through adopting symmetric key algorithm, reach the characteristic of one-way function, effectively protect authenticate key, and solved the problem of key lookup; Improved the efficient of key lookup, can resist the major part that faces between rfid interrogator and the label and attack, having comprised: eavesdropping; Follow the tracks of, illegally read, distort label data, the clone; Forge, man-in-the-middle attack, and can effectively protect the privacy of tag holder.

Description of drawings

Fig. 1 carries out the schematic flow sheet of two-way authentication for tag read-write equipment.

Fig. 2 is the ID of label and the synoptic diagram that concerns of corresponding authenticate key.

Fig. 3 is the synoptic diagram of read write line reading tag storer.

Fig. 4 writes the synoptic diagram of tag ram for read write line.

Fig. 5 is when guaranteeing integrity of data transmission, the synoptic diagram of read write line reading tag storer.

Fig. 6 is that read write line writes the synoptic diagram of tag ram when guaranteeing integrity of data transmission.

For the ease of understanding, below will describe in detail of the present invention through concrete accompanying drawing and embodiment.What need particularly point out is; Instantiation and accompanying drawing only are in order to explain; Obviously those of ordinary skill in the art can explain according to this paper, within the scope of the invention the present invention is made various corrections and change, and these corrections and change are also included in the scope of the present invention.

Embodiment

Embodiment 1

Fig. 1 is the two-way authentication flow process between rfid interrogator and the label, and comprising: authenticate key is searched, smart-tag authentication, and the read write line authentication, the key of data communication generates and authenticate key upgrades several steps.

Step 1, authenticate key is searched

Suppose that each label all has an independently key, when legal read write line and label communication, the key of how confirming current label fast is called authenticate key and searches problem.Simple solution is all authenticate keys in the read write line ergodic data storehouse; Use each key and label to carry out two-way authentication respectively; The defective of this method is when number of labels increases, and the read write line burden can sharply increase, and can not satisfy most of demands of applications.A kind of improving one's methods is for antilift wire quotation marks of each label distribution, when label is inquired about, at first returns call number separately, and read write line is searched corresponding authenticate key according to this call number.Since call number be fix and be plaintext transmission, this method exists follows the tracks of risk, assailant even can set up tab indexes number and the contact of label ID makes it face the privacy disclosure risk.The present invention proposes a kind of fast dynamic key lookup method, detailed process is following: each legal label can be assigned with an initial authentication key K when dispatching from the factory _Anthen ⁰, calculate the corresponding initial ID of label through one-way function H, be made as metaID ⁰, promptly ${\mathrm{MetaID}}^0=H\left(K_{\mathrm{Anthen}}^0\right),$ And with (metaID ⁰, K _Anthen ⁰) write tag ram.(metaID by all labels of database stores ⁰, K _Anthen ⁰) 0 the i time authentication begun before, read write line sends query statement Query, label returns current interim ID, is designated as metaID ⁱRead write line is with metaID ⁱAs the authenticate key K of index in this label correspondence of back-end data library lookup _Authen ⁱInterim ID will be updated after each authentication finishes, and not follow the tracks of and the privacy disclosure risk so this method does not exist.

Step 2, smart-tag authentication,

Read write line carries out authentication to the legitimacy of label.Read write line generates a random number R ₁Send to label; Label is used the current authentication key K _Authen ⁱTo R ₁Encryption obtains $\mathrm{<figure-callout\; id="1"\; label="S"\; filenames="H2009100481547E00022.png,H2009100481547E00031.png"\; state="\{\{state\}\}">S</figure-callout>}1=E({\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="H2009100481547E00022.png,H2009100481547E00031.png"\; state="\{\{state\}\}">R</figure-callout>}}_1,K_{\mathrm{Autnen}}^i),$ E (R wherein ₁, K _Authen ⁱ) represent with K _Authen ⁱAs key to plaintext R ₁Carry out the symmetric key encryption computing.Label generates a random number R ₂, utilize K _Authen ⁱEncryption obtains $S2=E(R_2,K_{\mathrm{Authen}}^i);$ Label sends to read write line with S1 and S2, in the accompanying drawing S1, and S2} representes junction symbol, promptly message is made up of S1 and S2.Read write line uses authenticate key K _Authen ⁱTo the S1 deciphering, if its decrypted result and R ₁Equate that then care label is legal; Otherwise label can not be through authentication, sign off.

Step 3, the read write line authentication,

Label carries out authentication to the legitimacy of read write line.Verified the legitimacy of label when read write line after, from $S2=E(R_2,K_{\mathrm{Authen}}^i)$ In decrypt the random number R that label generates ' ₂, with R ' ₂As key, encrypt R ₁, and with C ₂=E (R ₁, R ' ₂) send to label; Tag computation E (R ' ₁, R ₂), itself and C2 are compared, if identical, explain that read write line is legal; Otherwise read write line can not be through authentication, sign off.

Step 4, the key of data communication generates,

After read write line and label have been accomplished two-way authentication, if both sides are all legal, then can carry out the transmission of data, the data of transmission must be carried out with the ciphertext form.In the superincumbent verification process, the random number R that label produces ₂Be with the ciphertext transmission always, then can be with R ₂Key as both sides' data transmission.Because R ₂Be the disposable random number that label produces, improved the security of communication.

Step 5, authenticate key upgrades,

In order to guarantee that authenticate key has forward security, the key that adopts when promptly the assailant can not communicate by letter before the current key that obtains is extrapolated, security authentication process of the present invention is carried out real-time update to the authenticate key of label.Read write line generates random number R ₃, the legitimate secret with it during as label authentication next time, promptly $K_{\mathrm{Authen}}^{i+1}=R_3,$ Utilize one-way function H to calculate corresponding authenticate key metaID ^I+1, ${\mathrm{MetaID}}^{i+1}=H\left(K_{\mathrm{Authen}}^{i+1}\right),$ Promptly obtain the new (metaID of this label ^I+1, K _Authen ^I+1) right, read write line upgrades the key and the ID of this label; For with (metaID ^I+1, K _Authen ^I+1) writing label safely, read write line is with metaID ^I+1And K _Authen ^I+1Respectively with R ₂XOR obtains $\mathrm{\&alpha;}={\mathrm{MetaID}}^{i+1}\&CirclePlus;R_2$ With $\mathrm{\&gamma;}=K_{\mathrm{Authen}}^{i+1}\&CirclePlus;R_2,$ α and β are sent to label; After label receives, with α and β respectively with R ₂XOR promptly can obtain (metaID ^I+1, K _Authen ^I+1), and with (metaID ^I+1, K _Authen ^I+1) original (metaID of replacement ⁱ, K _Authen ⁱ).

In the authentication of i wheel, the interim ID of label, metaID ⁱAnd authenticate key K _Authen ⁱRelation shown in accompanying drawing 2, promptly ${\mathrm{MetaID}}^i=H\left(K_{\mathrm{Authen}}^i\right),$ Wherein H is one-way function (can not push away function input from functional value is counter).MetaID in verification process ⁱExpressly to return read write line, even the assailant obtains the one-way function algorithm, can not be from metaID ⁱCalculating K _Authen ⁱ, the one-way of function has improved authenticate key K _Authen ⁱConfidentiality.After the smart-tag authentication key updating, authenticate key still satisfies relation shown in the accompanying drawing 2 with interim ID.One-way function among the present invention only needs to realize at the read write line end, has reduced the hardware complexity of label, has practiced thrift the label cost.

After read write line, label two-way authentication were passed through, the data of read write line in can the reading tag storer perhaps write data to label.According to the requirement of communication security, the communication between them must be carried out with the form of ciphertext.The AES here can be consistent with the AES in the identifying procedure of front, and is perhaps different.Hereinafter represent AES, represent decrypt operation with Dec with Enc.

Fig. 3 is the flow process of read write line to the tag ram writing information, supposes that the information that will write is M ₁, read write line obtains corresponding ciphertext Cipher1=Enc (M after encrypting ₁, R ₂), read write line sends write command write, and (Cipher1 addr1), comprises the ciphertext Cipher1 that writes and writes address addr1 in the instruction; Label receive write command write (Cipher1, addr1) after, utilize key R ₂Deciphering obtains plaintext M to ciphertext Cipher1 ₁=Dec (Cipher1, R ₂), and with M ₁Corresponding address unit in the write store.Behind the label success writing information, return and write response of successful write_success.

Fig. 4 is the flow process of read write line reading tag memorizer information, supposes that the information that will read is M ₂, the address is addr2, read write line sends the Read (addr2) that reads instruction; Label is with the information M of address addr2 ₂Encryption obtains corresponding ciphertext Cipher2=Ennc (M ₂, R ₂), it is returned to read write line; Read write line utilizes key R ₂Deciphering obtains plaintext M to ciphertext Cipher2 ₂=Dec (Cipher2, R ₂).Need to prove the M at this place ₂M with the write operation of front ₁No correlativity.

In order to protect the sensitive data of label better, can in the intercommunication mutually of read write line label, increase the transmission information integrity.Data integrity is to obtain through the mode that the hash function computing information is made a summary.

The band completeness check to write the label flow process as shown in Figure 5: the plaintext of supposing transmission information is M ₁, read write line at first utilizes key R ₂It is encrypted, obtain ciphertext Cipher1=Enc (M ₁, R ₂), and with hash function Hash calculating M ₁Corresponding summary Hash (M ₁), through writing instruction ciphertext is sent to label then, label to ciphertext Cipher1 decipher obtain corresponding plaintext M ' ₁, calculate then its corresponding Hash (M ' ₁), with Hash (M ₁) compare with it, if consistent, then with M ' ₁It writes the storage unit of assigned address, writes response of successful with returning;

The band completeness check to read the label flow process as shown in Figure 6: at first send the Read (addr2) that reads instruction, label reads corresponding cleartext information M according to the address from storer ₂, calculate M with hash function Hash earlier ₂Corresponding summary Hash (M ₂), then to M ₂Encrypt, at last with M ₂Ciphertext Cipher2=Enc (M ₂, R ₂) and summary info Hash (M ₂) send read write line simultaneously to; Read write line at first to decrypt ciphertext obtain plaintext M ' ₂, calculate its corresponding summary info then, obtain Hash (M ' ₂), if Hash (M ' ₂) with the Hash (M that receives ₂) equate the data M of care label ₂Do not distorted, thereby guaranteed the tag storage information integrity.When label itself has independently HASH function calculation function calculate because label can carry out HASH to any data of memory block, so the time M ₂With M ₁There is not correlativity yet.

In sum, in order to prevent the random reading tag information of assailant, the individual privacy of protection tag holder prevents to follow the tracks of, and eavesdrops and distort attacks such as label data, and security authentication process of the present invention has been introduced the flow for authenticating ID to read write line; In order to prevent that the lawless person from cloning label, forge label, introduced identifying procedure to the label legitimacy.In order to prevent to reset and man-in-the-middle attack, safe procedures of the present invention has been used disposable random number.In order to guarantee the forward security of authenticate key, after the tag read-write equipment two-way authentication finished, read write line can upgrade authenticate key and the interim ID of label; Use one-way function from the interim ID of authenticate key computation tag, even the interim ID victim eavesdropping of label also can not be derived corresponding authenticate key.

The above; Only being preferred embodiment of the present invention, is not that the present invention is done any pro forma restriction, the those of ordinary skill of any affiliated technical field; If in the scope that does not break away from technical characterictic that the present invention carries; Utilize the equivalent embodiment of localized variation that disclosed technology contents is made or modification, and do not break away from technical characterictic content of the present invention, all still belong in the scope of technical characterictic of the present invention.

Claims (7)

1. a safety certifying method that is used for radio-frequency recognition system comprises smart-tag authentication and read write line authentication, it is characterized in that, comprises that also authenticate key is searched and authenticate key upgrades, and comprises the steps:

At first carry out key lookup, label receives the request access instruction, and label returns the interim ID of encryption, i.e. metaID ⁱ, wherein i=0...n is initial ID during i=0, the metaID of read write line to encrypt ⁱAs the corresponding authenticate key of index search

Carry out smart-tag authentication and read write line authentication then;

Described smart-tag authentication comprises that read write line carries out authentication to the legitimacy of label, and read write line generates a random number R ₁Send to label; Label is used the current authentication key

To R ₁Encryption obtains

Wherein

Expression with

As key to plaintext R ₁Carry out the symmetric key encryption computing, label generates a random number R ₂, utilize

Encryption obtains

Label sends to read write line with S1 and S2, and read write line uses authenticate key

To the S1 deciphering, if its decrypted result and R ₁Equate that then care label is legal; Otherwise label can not be through authentication, sign off;

After smart-tag authentication passes through, again read write line is carried out authentication, described read write line authentication comprises that label carries out authentication to the legitimacy of read write line, verified the legitimacy of label when read write line after, from In decrypt the random number R that label generates ' ₂, with R ' ₂As key, encrypt R ₁, and with C2=E (R ₁, R ' ₂) send to label; Tag computation E (R ' ₁, R ₂), itself and C2 are compared, if identical, explain that read write line is legal; Otherwise read write line can not be through authentication, sign off;

Read write line is also through after the authentication, with the key of R2 as the i data transfer;

Carry out authenticate key at last and upgrade, read write line generates the authenticate key of random number R 3 as communication

H calculates metaID with one-way function ^I+1, read write line upgrades the authenticate key and interim ID of this label, promptly And will

Safety writes label, during the i+1 time communication, uses

Replace original

2. safety certifying method according to claim 1 is characterized in that, said interim ID, i.e. metaID ⁱ, with authenticate key

Relation do, Wherein H is an one-way function.

3. safety certifying method according to claim 1 is characterized in that, said general

Safety writes label, comprises that read write line is with metaID ^I+1With

Respectively with R ₂XOR obtains

With

α and γ are sent to label; After label receives, with α and γ respectively with R ₂XOR promptly can obtain

And use

Replace original

4. safety certifying method according to claim 1 is characterized in that, the data transmission between said label and the read write line is all carried out with the ciphertext form, and the encrypted transmission flow process comprises,

When read write line during to the tag ram writing information,

Suppose that the information that will write is M ₁, read write line at first utilizes key R ₂It is encrypted, and read write line obtains corresponding ciphertext Cipher1=Enc (M after encrypting ₁, R ₂), Enc representes AES, read write line sends write command write, and (Cipher1 addr1), comprises the ciphertext Cipher1 that writes and writes address addr1 in the instruction; Label receive write command write (Cipher1, addr1) after, utilize key R ₂Deciphering obtains plaintext M to ciphertext Cipher1 ₁=Dec (Cipher1, R ₂), Dec representes decrypt operation, and with M ₁Corresponding address unit in the write store behind the label success writing information, returns and writes response of successful write_success.

5. safety certifying method according to claim 4 is characterized in that, described encrypted transmission flow process also comprises,

When read write line reading tag memorizer information,

Suppose that the information that will read is M ₂, the address is addr ₂, read write line sends the Read (addr2) that reads instruction; Label is with the information M of address addr2 ₂Use key R ₂Encryption obtains corresponding ciphertext Cipher2=Enc (M ₂, R ₂), Enc is an AES, and it is returned to read write line; Read write line utilizes key R ₂Deciphering obtains plaintext M to ciphertext Cipher2 ₂=Dec (Cipher2, R ₂), Dec is a decipherment algorithm.

6. safety certifying method according to claim 4 is characterized in that, when read write line writes data to label, also comprises data integrity verifying,

At first, the computing information summary,

The plaintext of supposing transmission information is M ₁, read write line at first utilizes key R ₂It is encrypted, obtain ciphertext Cipher1=Enc (M ₁, R ₂), and with hash function Hash calculating M ₁Corresponding informative abstract Hash (M ₁),

Then, carry out informative abstract relatively,

Read write line sends to label through writing instruction with ciphertext, label to ciphertext Cipher1 decipher obtain corresponding plaintext M ' ₁, calculate then its corresponding Hash (M ' ₁), with Hash (M ₁) and Hash (M ' ₁) relatively, if consistent, then with M ' ₁It writes the storage unit of assigned address, writes response of successful with returning.

7. safety certifying method according to claim 5 is characterized in that, read write line also comprises data integrity verifying during from the label read data,

At first, the computing information summary,

Read write line sends the Read (addr2) that reads instruction, and label reads corresponding cleartext information M according to the address from storer ₂, calculate M with hash function Hash earlier ₂Corresponding informative abstract Hash (M ₂),

Then, carry out the comparison of informative abstract,

To M ₂Encrypt, at last with M ₂Ciphertext Cipher2=Enc (M ₂, R ₂) and summary info Hash (M ₂) send read write line simultaneously to; Read write line at first obtains plaintext M to decrypt ciphertext ₂, calculate its corresponding summary info then, obtain Hash (M ' ₂), if Hash (M ' ₂) with the Hash (M that receives ₂) equate the data M of care label ₂Do not distorted, thereby guaranteed the tag storage information integrity.

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