Dual-link wireless ad hoc network and security defense method in emergency scene

A security defense method for a dual-link wireless ad hoc network in an emergency scene, comprising the steps of:

• (1) sending, by a source node ni, a secret key to its destination node nj, wherein:
• the RSA encryption module loaded on the source node ni encrypts the AES key Z1 through a private key Y of ni to obtain the encrypted AES key, and sends Z1 and the public key X of the source node ni to the destination node nj through the second link, wherein 1≤i≤M, 1≤j≤M, i≠j;
• (2) sending, by the source node ni, a message to its destination node nj, wherein:
• (2a) the Hash module loaded on the source node ni calculates the message A to be sent by the source node ni, and takes the calculated hash value as the message digest B of the message A;
• (2b) the digital signature module loaded on the source node ni signs the message digest B through the private key Y of the source node ni to obtain a digital signature C of B, and attaches the digital signature C to the message A to obtain the message D with the digital signature;
• (2c) the AES encryption module loaded on the source node ni encrypts D through the AES key Z of the source node ni to obtain an AES encrypted message E;
• (2d) if the AES encrypted message E is a security defense message, the source node ni sends the message to the destination node nj through the first link;
• if the AES encrypted message E is another message, the source node ni sends the message to the destination node nj through the second link;
• in the transmission process, if the destination node nj is not in the communication range of the source node ni, the message is forwarded through an intermediate node;
• (3) acquiring, by the destination node nj, the valid message, wherein:
• (3a) the destination node nj receives the encrypted AES key Z1 sent by the source node ni, the public key X of the source node ni and the AES encrypted message E;
• (3b) the RSA decryption module loaded on the destination node nj decrypts the encrypted AES key Z1 through the public key X of the source node ni to obtain the decrypted AES key Z2;
• (3c) the AES decryption module loaded on the destination node nj decrypts the AES encrypted message E through Z2 to obtain the AES decrypted message E′;
• (3d) the digital signature verification module loaded on the destination node nj strips the AES decrypted message E′ to obtain the message D′ and the digital signature C′ of E′;
• (3e) the digital signature verification module loaded on the destination node nj decrypts the digital signature C′ of E′ through the public key X of the source node ni to obtain message digest P;
• (3f) the Hash module loaded on the destination node nj calculates the message D′ and takes the calculated hash value as the message digest Q;
• (3g) the digital signature verification module loaded on the destination node nj judges whether the message digest P is the same as the message digest Q, if so, the message sent by the source node ni is consistent with the message received by nj, that is, the message received by nj is a valid message, otherwise, the message received by nj is an invalid message;
• (4) filtering, by the destination node nj, the abnormal message, wherein:
• (4a) the feature matching module loaded on the destination node nj matches the valid message with the abnormal message features in the abnormal message feature library, if they match successfully, the valid message is an abnormal message, and the abnormal message is filtered out to realize the defense against the abnormal message, otherwise, step (4b) is executed;
• (4b) the supervision engine module loaded on the destination node nj judges whether the valid message is normal through deep learning algorithm, if so, the valid message is a normal message, otherwise, the valid message is a new abnormal message, the features of the new abnormal message are added to the special broadcast queue module loaded on the destination node nj and the abnormal message feature library, and the new abnormal message is filtered out at the same time to realize the defense against the new abnormal message;
• (5) expanding, by the destination node nj, the abnormal message feature library, wherein:
• after receiving the normal message which is the security defense message in step (4b), the destination node nj adds the abnormal message features in the security defense message to the abnormal message feature library loaded on the destination node nj;
• (6) checking, by the new node to be added to the dual-link wireless ad hoc network in the emergency scene, its own security, wherein:
• the new node to be added to the dual-link wireless ad hoc network in the emergency scene is loaded with a security defense unit;
• its own hardware state is monitored by the S.M.A.R.T module to obtain the hardware state results of whether it is invaded and whether there is hardware failure;
• the supervision engine module checks whether its own identity and the hardware state monitored by the S.M.A.R.T module are normal;
• if so, it is authorized by the supervision engine module, and the authorization result information is added to the special broadcast queue module loaded on the new node through the supervision engine module;
• otherwise, the new node is refused to be added to the network to realize the defense against the new node with abnormality to be added to the dual-link wireless ad hoc network in the emergency scene;
• (7) sending, by the new node to be added to the dual-link wireless ad hoc network in the emergency scene, a security defense message to M mobile nodes, wherein:
• the new node to be added to the dual-link wireless ad hoc network in the emergency scene is taken as a source node, and its own encrypted AES key is acquired according to the method in step (1);
• the encrypted AES key and its own public key are sent to M mobile nodes of the dual-link wireless ad hoc network in the emergency scene through the second link, and its own AES encrypted security defense message is acquired according to the method in step (2) at the same time, and is sent to M mobile nodes of the dual-link wireless ad hoc network in the emergency scene through the first link;
• (8) acquiring, by M mobile nodes of the dual-link wireless ad hoc network in the emergency scene, the security defense message sent by the new node, wherein:
• M mobile nodes of the dual-link wireless ad hoc network in the emergency scene acquire the valid message sent by the new node according to the method in step (3), and judge whether the valid message is a normal message, an abnormal message or a new abnormal message according to the method in step (4);
• if the valid message is an abnormal message, the abnormal message is filtered out;
• if the valid message is a new abnormal message, the features of the new abnormal message are added to the special broadcast queue module loaded on M mobile nodes and the abnormal message feature library, and the new abnormal message is filtered out at the same time;
• otherwise, after the authorization result information of the new node in the normal message sent by the new node which is a security defense message is acquired, the new node is allowed to be added to the dual-link wireless ad hoc network in the emergency scene, and the dual-link wireless ad hoc network in the emergency scene of M+1 mobile nodes including the new node is obtained.