Authentication and key negotiation method, gateway, sensor and electronic equipment

A key agreement, sensor technology, applied in key distribution, can solve the problem of important data leakage, and achieve the effect of ensuring security and realizing anonymity

Pending Publication Date: 2022-04-08

HANGZHOU INNOVATION RES INST OF BEIJING UNIV OF AERONAUTICS & ASTRONAUTICS

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AI-Extracted Technical Summary

Problems solved by technology

In this case, the attacker may analyze the sensitive information of the target user through the identity information of the sensor node, and analyze th...

Method used

The authentication and key agreement method of the wireless sensor network of the present embodiment, adopts dynamic pseudo-random identification technology to realize the privacy protection of user and sensor node, promptly utilizes pseudo-random user identification and pseudo-random sensor identification to realize The anonymity of the sensor node is guaranteed, and the pseudo-random user identity and the pseudo-random sensor identity are updated after each successful authentication negotiation to realize the untraceability of the sensor node, and the co...

Abstract

The invention relates to an authentication and key negotiation method for a wireless sensor network, and the method comprises the steps: user equipment verifies the identity of a user through an intelligent card according to the identity information inputted by the user, and transmits login information to a gateway; the gateway verifies the identity of the user, generates access request information of the target sensor based on the first preset parameter of the gateway, and updates the first preset parameter of the gateway; the target sensor verifies the access request information, updates sensor preset parameters after verification is passed, generates a session key, and sends request passing information to the gateway; the gateway calculates the session key and verifies the request passing information, generates access confirmation information and updates a second preset parameter of the gateway; the user equipment calculates a session key, verifies the access confirmation information, and updates preset parameters of the smart card; the user equipment and the sensor communicate secretly using the session key. According to the method, anonymity and non-traceability of the nodes and confidentiality of communication are realized.

Application Domain

Key distribution for secure communicationEncryption apparatus with shift registers/memories +1

Technology Topic

AnonymityEngineering +7

Image

Examples

Experimental program(5)

Example Embodiment

[0066] Example 1

[0067] The authentication and key agreement method for a wireless sensor network in this embodiment is applied to a wireless sensor network. The wireless sensor network includes a sensor, a gateway, a smart card, and a user equipment. The user logs in to the target sensor through the user equipment and the smart card, and the user equipment can It is a terminal device such as a mobile phone, tablet, computer, etc., which is not limited here; there can be one or more sensors and gateways. Each sensor is connected to the gateway through a wireless network. The sensor is used to collect data and send the collected data to the gateway. The gateway processes the data and sends the processed data results to the user device; before the user logs in, he needs to register with the gateway first, and then perform security authentication and key negotiation through the gateway and the sensor.

[0068] figure 1 A schematic flowchart of an authentication and key agreement method for a wireless sensor network in an embodiment of the present application, as shown in figure 1 As shown, this embodiment includes:

[0069] S10, the user equipment verifies the user identity through the smart card according to the identity information input by the user, and sends login information to the gateway after the verification is passed, and the login information includes a pseudo-random user identity identifier;

[0070] S20. The gateway verifies the user identity according to the login information, and after the verification is passed, the access request information of the target sensor is generated based on the first preset parameter of the gateway, and the first preset parameter of the gateway is updated; the first preset parameter of the gateway includes the pseudo-random sensor identity. Identify and share keys between sensor nodes and gateway nodes;

[0071] S30. The target sensor verifies the access request information, updates the sensor preset parameters after the verification is passed, generates a session key, and sends request pass information to the gateway based on the session key and the updated sensor preset parameters, and the sensor preset parameters Including pseudo-random sensor identity, shared key between sensor nodes and gateway nodes;

[0072] S40. The gateway calculates the session key and verifies the request passing information. After the verification is passed, the access confirmation information is generated based on the second preset parameter of the gateway, and the second preset parameter of the gateway is updated. The second preset parameter of the gateway includes pseudo-random User identities, shared keys between users and gateway nodes;

[0073] S50, the user equipment calculates the session key and verifies the access confirmation information, and after the verification is passed, updates the preset parameters of the smart card, and the preset parameters of the smart card include a pseudo-random user identity and a shared key between the user and the gateway node;

[0074] S60, the user equipment and the sensor perform secure communication using the session key.

[0075] The authentication and key agreement method of the wireless sensor network in this embodiment adopts the dynamic pseudo-random identification technology to realize the privacy protection of the user and the sensor node, that is, the pseudo-random user identification and the pseudo-random sensor identification are used to realize the sensor node. The anonymity of the sensor node is achieved by updating the pseudo-random user ID and pseudo-random sensor ID after each authentication negotiation is successful, and the non-traceability of the sensor node is realized by updating the preset parameters of the current device. user data security.

[0076] In order to better understand the present invention, each step in this embodiment is described below.

[0077] S10. The user equipment verifies the user identity through the smart card according to the identity information input by the user, and sends login information to the gateway after the verification is passed, and the login information includes a pseudo-random user identity identifier.

[0078] In this embodiment, the user's identity information may include, but is not limited to, an identity identifier, an identity password, and a user's biometric feature. The smart card may be a single memory card, or may be a storage space designated in the client, which is not limited here. The preset parameters stored in the smart card are the parameters written into the smart card by the client and the gateway during the user's identity registration process.

[0079] In this embodiment, the smart card preset parameters also include a user registration verification value, an initial value of a user-side serial number, a hash function, a user identity information value, and a user biometric public parameter, and the preset parameters are generated when the user performs identity registration.

[0080] The user terminal can obtain the identity information input by the user, read the stored preset parameters from the smart card, and calculate the verification value according to the preset parameters and the identity information stored in the smart card. The validation value is used to validate the identity information entered by the user.

[0081] Specifically, in this embodiment, S10 includes:

[0082] S101, the user equipment obtains the identity information input by the user, and calculates a verification value according to the preset parameters of the smart card and the identity information;

[0083] S102, verifying the identity information by comparing the verification value with the user registration verification value;

[0084] S103. When the verification is passed, for the target sensor, based on the first key parameter information and the first authentication value generated by the hash function based on a first random number, the first random number is generated by a smart card;

[0085] S104. The user equipment sends the pseudo-random user identity, the timestamp, the first key parameter information and the first authentication value to the gateway as login information.

[0086] In this embodiment, a one-way hash function may be used for the parameter update method.

[0087] When each participant succeeds in each authentication negotiation, they will update the shared key between the user and the gateway node, and the shared key between the sensor node and the gateway node through the one-way hash function. Therefore, the attacker cannot obtain the previous shared key between the user and the gateway node, the shared key between the sensor node and the gateway node from the shared key this time, so as to realize the forwarding between the user, the gateway node and the sensor node. Security, which ensures the confidentiality of communications.

[0088] In this embodiment, the access request information further includes the update times of the first preset parameter of the gateway, then:

[0089] After the verification in S30 is passed, the method further includes: updating the shared key between the sensor node and the gateway node in the sensor preset parameter according to the update times of the first preset parameter of the gateway;

[0090] The sensor preset parameter further includes the sensor serial number, and the gateway first preset parameter further includes the sensor serial number on the gateway node side.

[0091] The access confirmation information also includes the update times of the second preset parameter of the gateway, then:

[0092] After the verification in S50 is passed, the method further includes: updating the shared key between the user and the gateway node in the preset parameters of the smart card according to the update times of the second preset parameters of the gateway;

[0093] The preset parameters of the smart card also include the user serial number, and the second preset parameters of the gateway also include the user identity and the user serial number on the gateway node side.

[0094] This embodiment adopts the serial number method to realize the anti-desynchronization attack of the protocol, that is, the user serial number and user serial number on the gateway node side, and the sensor serial number and sensor serial number on the gateway node side are used to realize the sensor node and gateway node, Synchronization between users and gateway nodes.

[0095] In this embodiment, S20 includes:

[0096] S201. The gateway receives the login information, and detects the time validity of the login information according to the timestamp in the login information;

[0097] S202, if the detection is passed, extract the user identity and the shared key between the user and the gateway node from the second preset parameter of the gateway according to the pseudo-random user identity;

[0098] S203, the gateway calculates an actual authentication value based on the user identity identifier, the shared key between the user and the gateway node, and the login information, and performs legality verification on the user identity;

[0099] S204, if the verification is passed, calculate the sensor identification and search for the existence of the sensor identification in the first preset parameter of the gateway;

[0100]S205, if it exists, based on the second key parameter information and the second authentication value generated by the hash function based on the second random number, the second random number is generated by the gateway;

[0101] S206, the gateway updates the pseudo-random user identity, the user serial number on the gateway node side, and the shared key between the user and the gateway node,

[0102] S207: The gateway sends the updated user serial number, timestamp, second key parameter information and second authentication value on the gateway node side to the target sensor as access request information.

[0103] In this embodiment, S30 includes:

[0104] S301. The target sensor receives the access request information, detects the time validity of the access request information according to the timestamp in the access request information, and detects the access request information according to the user serial number on the gateway node side synchronicity;

[0105] S302. If the detection is passed, update the shared key between the sensor node and the gateway node according to the user serial number on the gateway node side;

[0106] S303, calculating the actual authentication value based on the updated shared key between the sensor node and the gateway node, and verifying the validity of the gateway;

[0107] S304. If the verification is passed, the target sensor updates the pseudo-random sensor ID, the serial number on the sensor side, and the shared key between the sensor node and the gateway node;

[0108] S305. Generate third key parameter information and a third authentication value by using the hash function based on a third random number, where the third random number is generated by the target sensor;

[0109] S305: The target sensor sends the third key parameter information, the third authentication value, and the timestamp to the gateway as request pass information.

[0110] The method of this embodiment is an AKA protocol suitable for the WSNs environment, which can effectively prevent unauthorized access and ensure the availability and security of the WSNs communication.

Example Embodiment

[0111] Embodiment 2

[0112] In this embodiment, on the basis of Embodiment 1, the specific implementation process of the method proposed in the application is described in detail. The method includes four execution subjects: a user, a smart card, a sensor node and a gateway node, where the user refers to a device used by the user side, and the steps of the method include:

[0113] S1. Device initialization, including:

[0114] Step a1, the gateway node selects two random integers as the gateway node identity ID G and the gateway node master key K, and store it in the gateway node's memory;

[0115] Step a2, the gateway node selects the sensor node identification ID for the sensor node S , and store it in the memory of the sensor node;

[0116] Step a3, the gateway node pre-initializes all smart cards, and selects a smart card identity ID for each smart card SC and store it on the smart card.

[0117] S2, user registration and sensor node registration.

[0118] When a new user wants to access the data collected by sensor nodes in WSNs, it must complete legal registration with the gateway node, image 3 For a data flow diagram of the user registration process in another embodiment of the present application, please refer to image 3 , the user registration steps include:

[0119] Step b1, the new user inserts the smart card pre-assigned to him/her into the system card reader, and reads its identification ID SC And send it to the gateway node through the secure channel;

[0120] Step b2, when the gateway node receives the identity ID SC After that, first check whether it exists in the smart card database. If it exists, the gateway node returns the confirmation value Conf to the user. Otherwise, reject the registration request;

[0121] Step b3, the user sets the user identity ID U and user password PW U , and enter the user's biometric BIO through the biometric information collection device U. After that, the client generates a random number a i And calculate and generate the user biometric key BK i , User biological public parameter P i , pseudo-random user password MPW U :

[0122] Gen(BIO U )=(BK i ,P i )

[0123] MPW U =h(ID U ||PW U ||BK i ||a i )

[0124] Among them, h( ) represents the one-way hash function, and x||y represents the join operation on x and y.

[0125] will register information {id U , MPW U } to the gateway node through a secure channel;

[0126] Step b4, when the gateway node receives the registration information, it first detects the user identity ID U exists in the user database. If it exists, the gateway node rejects the registration request and asks the user to enter a new ID U. Otherwise, the gateway node computes the shared key K between the user and the gateway node GU and pseudo-random user ID MID U :

[0127] K GU =h(ID U ||ID G ||MPW U ||K)

[0128] MID U =h(ID U ||ID G ||K GU )

[0129] Among them, K represents the gateway node master key.

[0130] Set the initial value of the serial number NU i =NU i0 =0, where NU i0 Indicates the serial number of the user side, NU i Indicates the user serial number on the gateway node side, and calculates the user registration verification value D i :

[0131] D i =h(ID U ||K GU ||MPW U )mod n 0

[0132] where n 0 for 2 4 and 2 8 integers between.

[0133] After that put info U ,MID U ,K GU ,NU i stored in the user database. At the same time, the gateway node initializes the value FAIL, which records the number of user login failures, to NULL. Finally, the gateway node puts the information < MID U ,D i ,K GU ,NU i0 ,FAIL,h( )>Write to the smart card and send it to the user through a secure channel;

[0134] Step b5, when the user receives the information from the gateway node, calculate the user identity information value A i , and put information i ,P i write to smart card,

[0135]

[0136] in, Represents an XOR operation.

[0137] Ultimately, the smart card contains the information < MID U ,A i ,D i ,P i ,K GU ,NU i0 ,FAIL,h(·)>.

[0138] When sensor nodes need to join WSNs and perform data collection, they must complete legal registration with gateway nodes. Figure 4 For a data flow diagram of the sensor registration process in another embodiment of the present application, please refer to Figure 4 , the sensor registration steps include:

[0139] Step c1, the new sensor node sends the sensor node identification ID through the secure channel S to the gateway node;

[0140] Step c2, when the gateway node receives the identity ID S After that, first check whether it exists in the sensor node database. If not present, the gateway node rejects the registration request. Otherwise, the gateway node generates a random number m j and calculate the shared key K between the sensor node and the gateway node GS , Pseudo-random sensor identification MID S :

[0141] K GS =h(ID S ||ID G ||K||m j )

[0142] MID S =h(ID S ||ID G ||K GS )

[0143] The gateway node sets the initial value of the serial number NS k =NS k0 =0, where NS k is the sensor serial number on the gateway node side, NS k0 is the serial number on the sensor node side, and stores the information S ,MID S , K GS ,NS k to the sensor data sheet. Finally, the message {MID is sent over the secure channel S ,K GS ,NS k0 } to the sensor node;

[0144] Step c3, after receiving the information from the gateway node, the sensor node sends the information {MID S ,K GS ,NSk0 } Store to memory and delete the identity ID S.

[0145] S3. User login and authentication negotiation.

[0146] It should be noted that, in the following embodiments, the parameters marked with * are the parameters input or generated during the user login and authentication negotiation process, or the same parameters saved in different devices. The meanings of the parameters are the same as those in S1 and S2. The same, and will not be described one by one below.

[0147] When a user needs to obtain the data collected by a certain sensor node, he/she needs to log in to the gateway node first. Figure 5 For a data flow diagram of the wireless sensor network authentication and key agreement process in another embodiment of the present application, please refer to Figure 5 , the user login and authentication negotiation process includes:

[0148] Step d1, the user inserts the smart card into the card reader and inputs the user identification ID U and user password PW U and enter After the smart card calculation:

[0149]

[0150]

[0151]

[0152]

[0153] Will with D stored in it i Compare. If the two are not equal, the login request is rejected and the value of FAIL is incremented by 1. When the value of FAIL exceeds the preset threshold, the smart card is considered to be insecure, and it is suspended until the user re-registers. Otherwise, the smart card completes the verification of the user's legitimacy and executes the subsequent process.

[0154] Smart card to generate random number R i and get the current timestamp T 1. After that, the user selects the sensor node that he wants to access, and calculates the temporary sensor identification TID s :

[0155]

[0156]

[0157] V 1 =h(ID U ||R 1 ||K GU ||T 1 )

[0158] Finally, the user will log in with the information Msg1:{MID U ,M 1 ,V 1 ,T 1 } Send to the gateway node through the common channel;

[0159] Step d2, when the gateway node receives the login information Msg1 from the user, it first checks the validity of the timestamp. The gateway node gets the current time and with the received time T 1 Compare. if exceeds the preset threshold - the maximum transmission delay time ΔT, the session is terminated. Otherwise, the gateway node identifies the MID by a pseudo-random user identity U Extract the corresponding ID from the user database U and K GU. After that, the gateway node computes:

[0160]

[0161]

[0162] Will with the received V 1 Compare. If the two are not equal, terminate the session. Otherwise, the gateway node confirms the legitimacy of the user, and calculates the sensor node identification ID by the following formula S and search for the identity ID in the sensor database S does it exist.

[0163]

[0164] If it exists, the gateway node extracts the corresponding MID S and K GS. After that, the gateway node generates a random number R j , get the current timestamp T 2 , and compute:

[0165]

[0166] V 2 =h(ID U ||R i ||R j ||K GS ||NS k ||T 2 ).

[0167] Finally, the gateway node updates K respectively by the following formulas GS , MID S and NS k , and send the message Msg2:{M through the common channel 2 ,V 2 ,NS k ,T 2 } to the sensor node.

[0168] K GS =h(K GS )

[0169] MID S =h(ID S ||ID G ||K GS )

[0170] NS k =NS k +1

[0171] Step d3, when the sensor node receives the information Msg2 from the gateway node, it first detects and NS k -NS k0 Whether ≥1 is established. If not, terminate the session. Otherwise, the sensor node orders:

[0172] N=NS k -NS k0

[0173]

[0174] and compute N–1 times After that, the sensor node computes:

[0175]

[0176]

[0177] and will with the received V 2 Compare. If the two are equal, the sensor node passes

[0178] K GS =h(K GS * ||ID S ||ID G )

[0179] MID S =h(ID S ||ID G ||K GS )

[0180] NS k0 =NS k

[0181] Update K separately GS , MID S and NS k0. Next, the sensor node generates a random number R k , get the current timestamp T 3 and calculate:

[0182] SK=h(ID U ||ID G ||ID S ||R i ||R j ||R k )

[0183]

[0184] V 3 =h(MID S ||ID U ||SK||R k ||NS k0 ||T 3 )

[0185] Among them, SK is the session key.

[0186] Finally, the sensor node sends the message Msg3:{M through the common channel 3 ,V 3 ,T 3 } to the gateway node;

[0187] Step d4, when the gateway node receives the information Msg3 from the sensor node, it first detects T 3 freshness, and compute:

[0188]

[0189]

[0190]

[0191] After that, the gateway node will with the received V 3 Compare. If the two are not equal, terminate the session. Otherwise, the gateway node gets the current timestamp T 4 and calculate:

[0192]

[0193] V 4 =h(ID U ||MID U ||SK||R j ||NU i ||T 4 )

[0194] Then pass:

[0195] K GU =h(K GU ||ID U )

[0196] MID U =h(MID U ||ID G ||K GU )

[0197] NU i =NU i +1

[0198] Update K separately GU , MID U and NU i. Finally, the gateway node sends the message Msg4:{M through the common channel4 ,V 4 ,NU i ,T 4 } to the user;

[0199] Step d5, when the user receives the information Msg4 from the gateway node, first detect -T 4 | i -NU i0 Whether ≥1 is established. If not, terminate the session. Otherwise, the user sets M=NU i -NU i0 and and compute M–1 times After that, the user computes:

[0200]

[0201] SK=h(ID U ||ID G ||ID S ||R i ||R j ||R k )

[0202]

[0203] Next, the user will with the received V 4 Compare. If equal, the user passes

[0204] K GU =h(K GU * ||ID U )

[0205] MID U =h(MID U ||ID G ||K GU )

[0206] NU i0 =NU i

[0207] Update K separately GU , MID U and NU i0. Finally, the user completes the authentication and negotiation process.

[0208] In this embodiment, the serial number method is used to realize the anti-desynchronization attack of authentication and negotiation, that is, using NU respectively i and NU i0 , NS k and NS k0 To achieve synchronization between users and gateway nodes, sensor nodes and gateway nodes, maintain the consistency between users, gateway nodes and sensor nodes, so as to avoid the attackers blocking the authentication negotiation process. The synchronization process is interrupted.

[0209] In this embodiment, it can also include

[0210] S4. The user updates the password or biometric information.

[0211] Image 6 For a data flow diagram of the password and biometric key update process in another embodiment of the present application, please refer to Image 6 , when the user needs to update the password or biometric information, he/she needs to perform the following process.

[0212] Step e1, the user inserts the smart card into the card reader and inputs the ID U and PW U and enter Smart Card Computing:

[0213]

[0214]

[0215]

[0216]

[0217] After that, the smart card will with D stored in it i Compare. If the two are not equal, the smart card rejects the update request for the password/biometric information. Otherwise, the smart card confirms the user's legitimacy and allows the user to enter a new user password or new user biometrics At the same time, the smart card generates a random number b i and get the current timestamp T c1 , and then compute:

[0218]

[0219]

[0220]

[0221]

[0222] Finally, the request information {MPW U ,M c1 ,V c1 ,T c1 } Send to the gateway node;

[0223] Step e2, when the gateway node receives the request information from the user, it first detects T c1 freshness. If the conditions are met, the gateway node passes the MID U Search for the corresponding ID in the user database U , K GU and MPW U , and compute:

[0224]

[0225]

[0226] After that, the gateway node detects V c1 * =V c1 Whether it is true, if true, the gateway node generates a random number n j and get the current timestamp T c2. Then calculate:

[0227]

[0228]

[0229]

[0230]

[0231] Finally, the gateway node will reply with the message {M c2 ,V c2 ,T c2 } Send to the user and update the corresponding data;

[0232] Step e3, when the smart card receives the reply information from the gateway node, it first detects T c2 freshness. If the conditions are met, the smart card calculates:

[0233]

[0234]

[0235]

[0236]

[0237] After that, smart card detection Is it equal, if so, the smart card calculates:

[0238]

[0239]

[0240] put D in memory i ,A i ,P i ,MID U and K GU replace with Otherwise, the client immediately terminates this phase and retries the password/biometric information update process.

[0241] It should be noted that, in this embodiment, the information M of key parameters is transmitted between the user, the gateway node and the sensor node. 1 ,M 2 ,M 3 ,M 4 ,Mc 1 ,Mc 2 Symmetric encryption algorithm can also be used; information V used for mutual authentication of users, gateway nodes and sensor nodes 1 ,V 2 ,V 3 ,V 4 ,Vc 1 ,Vc 2 A message authentication code based on a hash function can also be used.

[0242] The invention proposes a safe and lightweight identity authentication method. The method is based on the combination of hash function and XOR operation, and adopts a three-factor authentication method combining user password, user biometric feature and smart card, so as to reduce the impact of identity authentication protocol on sensors. The energy consumption caused by the network can improve the efficiency of the sensor network.

Example Embodiment

[0243] Embodiment 3

[0244] A second aspect of the present application provides a sensor through Embodiment 3, Image 6 A schematic diagram of the sensor structure in the third embodiment of the present application, such as Image 6 shown, the sensor includes:

[0245] The first verification module 11 is used to verify the access request information;

[0246] The parameter updating module 12 is used to update the sensor preset parameters after the verification is passed, and the sensor preset parameters include a pseudo-random sensor identification, a shared key between the sensor node and the gateway node;

[0247] The key generation module 13 is used to generate a session key, and sends request pass information to the gateway based on the session key and the updated sensor preset parameters;

[0248] The first communication module 14 is configured to perform secure communication with the user equipment by using the session key.

[0249] The sensor provided in this embodiment can be used to execute the steps in the foregoing method embodiments that use the sensor as an execution subject, and the implementation principle and technical effect thereof are similar, and are not repeated here in this embodiment.

PUM

Description & Claims & Application Information

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Virtual reality equipment as well as method and device for monitoring ground obstacles under using scene of virtual reality equipment

InactiveCN105807920Aensure safetySecurity

Owner:BEIJING PICO TECH

Block chain hidden data segmentation transmission method

PendingCN114567427Astrong anonymityachieve anonymity

Owner:BEIJING INSTITUTE OF TECHNOLOGYGY

Classification and recommendation of technical efficacy words

achieve anonymity
ensure safety

Block chain hidden data segmentation transmission method

PendingCN114567427Astrong anonymityachieve anonymity

Owner:BEIJING INSTITUTE OF TECHNOLOGYGY

Authentication and key negotiation method, gateway, sensor and electronic equipment

A key agreement, sensor technology, applied in key distribution, can solve the problem of important data leakage, and achieve the effect of ensuring security and realizing anonymity

AI-Extracted Technical Summary

Problems solved by technology

Method used

Abstract

Image

Examples

Example Embodiment

Example Embodiment

Example Embodiment

PUM

Description & Claims & Application Information

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