Disclosure of Invention
The invention aims to provide an SSL VPN remote access method, system and related device supporting a post quantum algorithm, so as to solve the technical problems in the prior art, and provide anti-quantum protection.
In a first aspect, the present invention provides an SSL VPN remote access method supporting a post quantum algorithm, applied to a client, so that the client accesses a target server remotely through a VPN server, the method includes:
Establishing a PQC secure channel with a VPN server to negotiate and determine a key and identity authentication;
Encrypting the original data by using the negotiated encryption key, and transmitting the encrypted data to the VPN server;
The encrypted data is decrypted by the VPN server by using the negotiated decryption key and then sent to the target server.
The SSL VPN remote access method supporting the post quantum algorithm as described above, wherein preferably, the client establishes a PQC secure channel with the VPN server to negotiate and determine a key and identity authentication, including:
Transmitting a first random number, a session ID, a supported protocol version and a supported algorithm type to the VPN server;
Receiving a first post quantum algorithm public key, a second random number, a session ID, a selected protocol version and a selected algorithm sent by the VPN server, so as to confirm that the client and the VPN server communicate based on the same parameters;
acquiring a server signature sent by the VPN server, wherein the server signature is obtained by signing VPN server information by the VPN server through a second post quantum algorithm private key;
Verifying the signature of the server by using the built-in second post quantum algorithm public key, and confirming the identity of the VPN server;
Packaging a premaster secret key and a ciphertext of the premaster secret key by using a first post quantum algorithm public key, reserving the premaster secret key, generating a master secret key by using a first random number, a second random number and the premaster secret key, deriving a session secret key according to the master secret key, and then sending the ciphertext to a VPN server;
After the ciphertext is decrypted by the VPN server, the session key is also generated by the VPN server, the client and the VPN server mutually verify session keys of the two parties, and after the session key is successfully verified, the client uses the session key to carry out encrypted communication with the VPN server.
The SSL VPN remote access method supporting the post quantum algorithm as described above, wherein preferably, the client establishes a PQC secure channel with the VPN server to negotiate and determine a key and identity authentication, including:
Transmitting a first random number, a session ID, a supported protocol version and a supported algorithm type to the VPN server;
receiving a second random number, a session ID, a selected protocol version and a selected algorithm sent by the VPN server to confirm that the client and the VPN server communicate based on the same parameters;
Packaging a premaster secret key and a ciphertext of the premaster secret key by using a first post quantum algorithm public key, reserving the premaster secret key, generating a master secret key by using a first random number, a second random number and the premaster secret key, deriving a session secret key according to the master secret key, and then sending the ciphertext to a VPN server;
After the ciphertext is decrypted by the VPN server, the session key is also generated by the VPN server, the client and the VPN server mutually verify session keys of the two parties, and after the session key is successfully verified, the client uses the session key to carry out encrypted communication with the VPN server.
An SSL VPN remote access method supporting a post quantum algorithm as described above, wherein, preferably,
The session key is also generated by the VPN server;
The client and the VPN server respectively construct a Finished message, wherein the Finished message comprises a session key, a fixed character string and a hash value of handshake information, and the client and the VPN server encrypt the Finished message by using the session key;
the encrypted Finished message is sent to the opposite party, the receiver decrypts the received Finished message by using the session key, the receiver calculates a hash value theoretically contained in the Finished message and compares the hash value with the hash value in the decrypted Finished message, if the hash values are matched, the sender is informed of using the correct session key, and the handshake message is not tampered;
And if the Finished message is successfully authenticated, the client and the server carry out encrypted communication by using the session key.
The SSL VPN remote access method supporting the post quantum algorithm as described above, wherein preferably, the algorithm supported by the client adopts any one of the following:
a post quantum algorithm;
A national encryption algorithm;
International classical algorithms;
a first hybrid algorithm based on the post quantum algorithm and the cryptographic algorithm;
A second hybrid algorithm based on the post quantum algorithm and the international classical algorithm;
a third hybrid algorithm based on the national cryptographic algorithm and the international classical algorithm;
And a fourth hybrid algorithm based on the post quantum algorithm, the national cryptographic algorithm and the international classical algorithm.
In the SSL VPN remote access method supporting the post quantum algorithm, it is preferable that the first post quantum algorithm is a post quantum cryptography encapsulation algorithm, and the second post quantum algorithm is a post quantum cryptography signature algorithm.
In a second aspect, the present invention provides an SSL VPN remote access system, including a client, a VPN server and a target server, where the client has an application, a first VPN function module and a first network interface that are sequentially signal connected, the VPN server has a second network interface, a second VPN function module and a forwarding module that are sequentially signal connected, and the target server has a plurality of service modules, where:
the application program sends original data to the first VPN functional module, and the first VPN functional module and the second VPN functional module establish a PQC secure channel so as to negotiate and determine a key; the first VPN function module encrypts original data by using the negotiated encryption key, and the encrypted data is sent to the first network interface by the first VPN module;
after the second network interface receives the encrypted data sent by the first network interface, the encrypted data is transferred to the second VPN functional module, the second VPN functional module decrypts the encrypted data by using the negotiated decryption key and sends the decrypted data to the forwarding module, and the forwarding module forwards the decrypted data to the corresponding service module of the target server.
An SSL VPN remote access system as described above, wherein preferably, the first VPN functional module establishes a PQC secure channel with the second VPN functional module, comprising:
The first VPN function module sends a first random number, a session ID, a supported protocol version and a supported algorithm type to the second VPN function module;
the second VPN functional module selects a protocol version and an algorithm supported by the second VPN functional module from protocol versions and algorithm types supported by the first VPN functional module, and sends a selection result, a first post quantum algorithm public key, a second random number and a session ID to the first VPN functional module; the second VPN function module signs VPN server information by using a second postquantum algorithm private key to obtain a server signature, and sends the server signature to the first VPN function module;
The first VPN functional module verifies the server signature by using a built-in second post quantum algorithm public key, packages a premaster secret key and a ciphertext of the premaster secret key by using the first post quantum algorithm public key, reserves the premaster secret key, generates a master secret key by using a first random number, a second random number and the premaster secret key, derives a session secret key according to the master secret key, and then sends the ciphertext to a VPN server;
The second VPN function module receives the ciphertext sent by the first VPN function module, decrypts the ciphertext by using a first post quantum algorithm key to obtain a premaster secret key, and generates a session key by using the first random number, the second random number and the premaster secret key;
The first VPN function module and the second VPN function module mutually authenticate the session key.
In a third aspect, the present invention provides an electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, characterized in that the processor implements the aforementioned method when executing the computer program.
In a fourth aspect, the present invention provides a computer readable storage medium having stored thereon a method of performing the foregoing.
Compared with the prior art, the invention establishes the PQC secure channel between the client and the VPN server, the PQC secure channel is used for negotiating and determining the secret key and the identity authentication, the encrypted data is sent to the VPN server through the established PQC secure channel, in the process, the data is encrypted by the post quantum algorithm, and the data is protected from being read or tampered by an unauthorized third party, so that the protection against the attack of a quantum computer can be provided, and the security of the secret key exchange process is ensured.
Detailed Description
The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the invention.
Referring to fig. 1, an embodiment of the present invention provides an SSL VPN remote access method supporting a post quantum algorithm, which is applied to a client, so that the client accesses a target server remotely through a VPN server, in a possible implementation manner, the client has an application program, a first VPN function module and a first network interface that are sequentially connected by signals, the VPN server has a second network interface, a second VPN function module and a forwarding module that are sequentially connected by signals, and the target server has a plurality of service modules, and the method includes the following steps:
step S101, a PQC secure channel is established with a VPN server to negotiate and determine a secret key and identity authentication, the secure channel is constructed based on a post quantum cryptography algorithm (PQC), the channel is used for negotiating and determining the secret key and the identity authentication, and the post quantum cryptography algorithm can provide protection against quantum computer attacks and ensure the security of a secret key exchange process.
Specifically, the application program sends the original data to the first VPN function module, and a PQC secure channel is established between the first VPN function module and the second VPN function module, where the secure channel is established to negotiate a cryptographic key used by both parties of communication and perform identity authentication.
After the PQC secure channel is established, the first VPN function module and the second VPN function module perform key agreement. This process involves the use of post quantum cryptography algorithms to protect key exchanges, ensuring that the security of key exchanges is guaranteed even in the quantum computing era. And the first VPN function module and the second VPN function module can also carry out identity authentication at the same time of key negotiation so as to ensure that the identities of the two communication parties are credible.
And step S102, encrypting the original data by using the negotiated encryption key, and transmitting the encrypted data to the VPN server.
Specifically, the first VPN function module encrypts the original data using the negotiated encryption key, the encrypted data is sent to the first network interface by the first VPN module, and once the secure channel is established, the client and the VPN server encrypt the original data using the negotiated encryption key.
The first network interface sends the encrypted data to a second network interface of the VPN server, and the second network interface receives the encrypted data sent by the first network interface and then sends the encrypted data to a second VPN functional module.
And step S103, the encrypted data is decrypted by the VPN server by using the negotiated decryption key and then is sent to the target server.
Specifically, after the second VPN function module in the VPN server receives the encrypted data sent from the second network interface, the data are decrypted by using a decryption key determined by a key negotiation process before, which ensures the security of the data in the transmission process and prevents an unauthorized third party from accessing or tampering with the data.
The decrypted data is sent to a forwarding module of the VPN server. The forwarding module is responsible for forwarding data from the VPN server to a destination server on the internal network or the internet. And the forwarding module forwards the decrypted data to a corresponding service module of the target server. This traffic module is the part of the target server responsible for handling the specific traffic logic, which receives and processes data from the VPN.
After the service module of the target server receives the data, further processing, such as storing, calculating or responding to the request of the client, is performed on the data according to the service requirement. If the service module needs to return a response to the client, the service module sends response data back to the forwarding module of the VPN server, then the forwarding module sends the response data to the second VPN function module, and the second VPN function module encrypts the response data and sends the response data back to the client through the second network interface. After receiving the encrypted response data, the first VPN function module of the client decrypts the data by using the corresponding decryption key, and displays the decrypted data to a user or further processes.
In a first possible implementation, referring to fig. 2, a PQC secure channel is established with a VPN server to negotiate a deterministic key and identity authentication, comprising the steps of:
And step S1011, transmitting the first random number, the session ID, the supported protocol version and the supported algorithm type to the VPN server, and receiving the first post-quantum algorithm public key, the second random number, the session ID, the selected protocol version and the selected algorithm transmitted by the VPN server to confirm that the client and the VPN server communicate based on the same parameters.
Specifically, the first random number is used in subsequent key generation and verification processes. Preferably, the first random number is a quantum random number, and the quantum random number (Quantum Random Number, QRNG) is a random number generated based on the quantum mechanical principle, and has unpredictability and no periodicity so as to ensure the safety and reliability in the communication process.
The protocol version sent by the first VPN function determines the specifications and rule framework to which the subsequent communications of both parties follow, and defines the rules and steps that must be followed in the communication process, including how to establish a connection, how to exchange information, and how to handle errors, etc. The kind of algorithm is related to the subsequent security related operations such as encryption, signature, etc. to establish the initial parameters of the communication.
After the second VPN functional module receives the information of the first VPN functional module, screening is started from the protocol version and algorithm type set provided by the first VPN functional module, a proper option is determined based on configuration of a system, a preset security policy and supporting capability of various protocols and algorithms, and after the selection is determined, the second VPN functional module clearly informs the first VPN functional module of which protocol version and algorithm type is specifically selected, so that the first VPN functional module knows that subsequent communication will be performed according to the protocol version and algorithm type.
In addition, the second VPN function module also generates and transmits a second random number to the first VPN function module, where the second random number is similar to the first random number sent by the first VPN function module and is also used for subsequent operations such as generating a session key, and preferably, the second random number is also a quantum random number. The randomness and confidentiality of the key generation are further enhanced by providing random numbers for the two parties respectively.
By exchanging random numbers and validating protocol versions and algorithms, the first VPN function module and the server validate that they use the same communication rules and security measures, thereby establishing a secure communication channel.
In the embodiment provided by the invention, the first VPN functional module is internally provided with the second post-quantum algorithm public key, the second VPN functional module is internally provided with the first post-quantum algorithm public key and the second post-quantum algorithm private key, in a feasible implementation mode, the first post-quantum algorithm is a post-quantum password packaging algorithm, the first post-quantum password packaging algorithm is exemplified as Kyber algorithm, and the Kyber algorithm is a grid-based public key encryption scheme and is used for key packaging and other operations. The second VPN function module sends Kyber the public key to the first VPN function module for use in subsequent key encapsulation and decryption operations to construct a two-party secure communications key hierarchy. The second post quantum algorithm is a post quantum cryptographic signature algorithm. The second post quantum cryptographic signature algorithm is illustratively Dilithium algorithm, dilithium algorithm is a lattice-based digital signature scheme, and is used for identity verification and other operations.
Step S1012, the server signature sent by the VPN server is obtained, wherein the server signature is obtained by the VPN server signing the VPN server information by using a second post quantum algorithm private key, and the built-in second post quantum algorithm public key is used for verifying the server signature and confirming the identity of the VPN server.
Specifically, the server signature is obtained by signing the related information by the second VPN function module by using a built-in Dilithium private key, the first VPN function module is built with a Dilithium public key, the second VPN function module proves the identity legitimacy of the second VPN function module to the first VPN function module in a private key-based signature mode, only the party with the corresponding Dilithium private key can generate a correct signature, and the first VPN function module can verify through the corresponding Dilithium public key. If the verification is passed, the second VPN function module currently communicating with the second VPN function module is legal and has a party with a corresponding private key, so that the identity of the second VPN function module is confirmed, a foundation is laid for subsequent safe and reliable communication, and if the verification is failed, the second VPN function module possibly means that safety risks exist, such as the situation of encountering man-in-the-middle attack and the like, and the communication is interrupted.
Through the steps, the first VPN function module can ensure the authenticity of the identity of the second VPN function module and the safety of communication, and meanwhile, the process utilizes the characteristics of a post quantum algorithm to resist the threat of quantum computation.
Step S1013, a pre-master key and ciphertext of the pre-master key are packaged by using the first post-quantum algorithm public key, the pre-master key is reserved, the first random number, the second random number and the pre-master key are used for generating the master key, a session key is derived according to the master key, and then the ciphertext is sent to the VPN server.
After confirming the identity of the second VPN function module, the first VPN function module performs a key encapsulation operation by using the Kyber public key sent by the previous second VPN function module, and in this process, a premaster secret key and a corresponding ciphertext form (i.e., cipher) are generated by combining a specific key encapsulation algorithm with relevant parameters.
The premaster secret is typically a randomly generated random number, preferably a quantum random number, used for subsequent session encryption, and is encrypted as Cipher to ensure that it is not compromised during transmission to the second VPN functional module, ensuring its confidentiality. Then, the first VPN functional module may send Cipher to the second VPN functional module, and enter the next round of interaction link.
Step S1014, after the ciphertext is decrypted by the server, the session key is also generated by the server, the client and the server mutually verify the session keys of the two parties, and after the session key is successfully verified, the client uses the session key to carry out encrypted communication with the server.
Specifically, after receiving the Cipher sent by the first VPN function module, the second VPN function module decrypts the Cipher by using its own Kyber private key, and only the private key matched with the Kyber public key has a specific mathematical correspondence relationship with the private key, so that the ciphertext generated by encrypting the corresponding public key can be correctly decrypted. Through the decryption process, the second VPN function module can successfully obtain the plaintext content of the premaster secret.
After the ciphertext is decrypted by the second VPN function module, the second VPN function module is provided with necessary elements for generating a session key, namely a first random number, a second random number and a premaster key, the second VPN function module uses the same algorithm, generates a master key by combining the first random number, the second random number and the premaster key, and derives the session key according to the master key.
To ensure that the session keys calculated by the two parties are completely consistent and not tampered with, the two parties will send a Finished message encrypted with the session key to each other, and the first VPN function module and the second VPN function module each construct a Finished message, where the Finished message includes the session key, a fixed string (e.g., "SERVER FINISHED" or "CLIENT FINISHED"), and a hash value of all exchanged messages from the beginning of the handshake, where the hash value includes a hash of all previously handshake messages to ensure the integrity of the message. The first VPN function and the second VPN function encrypt the Finished message using a session key that was generated during a previous key exchange, ensuring that only parties that have the correct session key can decrypt the message.
The encrypted Finished message is sent to the opposite party, the receiver decrypts the received Finished message by using the session key, the receiver calculates the hash value theoretically contained in the Finished message and compares the hash value with the hash value in the decrypted Finished message, if the hash values are matched, the sender uses the correct session key, and the handshake message is not tampered.
And if the Finished message is successfully verified, the first VPN functional module and the second VPN functional module carry out encrypted communication by using the session key.
Taking the message sent by the first VPN function module as an example, the message plaintext structure of the message has a strict design, firstly, hash operation is performed on all the messages sent by the two parties to obtain a hash value, and then the hash value is integrated with the session key and the fixed character string CLIENT FINISHED to perform hash operation again. The first VPN function module encrypts the message by using the session key and sends the encrypted message to the second VPN function module, the second VPN function module decrypts the message by using the same session key after receiving the message, calculates a hash value according to the same rule by itself, and compares the two hash values. If the two are consistent, the correct session key used by the two parties is indicated, and the message in the whole session process is not tampered, so that the integrity and the safety of communication are ensured. The second VPN function will then also generate a message ("SERVER FINISHED") encrypted with a similar structure but replacing the fixed string to send to the first VPN function for the same authentication operation. This not only verifies that both parties have calculated the correct session key, but also ensures that both parties' session messages have not been tampered with.
After the key verification step, the first VPN functional module and the second VPN functional module already determine the consistent and safe and reliable session key, on the basis, the first VPN functional module and the second VPN functional module can use the session key to encrypt communication contents, so that the communication data is kept secret in the network transmission process, and only two parties with the correct session key can decrypt and restore the encrypted contents, thereby realizing safe communication.
In a possible implementation, the algorithm supported by the first VPN function module adopts any one of the following:
Post quantum algorithms, providing data protection against quantum security to ensure data security under the quantum computing age, include one or more of Kyber and Dilithum algorithms.
The national cryptographic algorithm refers to a cryptographic algorithm approved by the national cryptographic authority, and comprises one or more algorithms of SM1, SM2, SM3, SM4, SM7, SM9 and ZUC.
The international classical algorithm refers to a cryptographic algorithm widely used internationally, including one or more of AES, RSA and ECDSA.
The first hybrid algorithm based on the post quantum algorithm and the national encryption algorithm combines the post quantum algorithm and the national encryption algorithm to provide a more flexible security solution. This hybrid approach can introduce post-quantum algorithms to address future security challenges while maintaining traditional algorithm compatibility.
Based on the second hybrid algorithm of the post quantum algorithm and the international classical algorithm, the post quantum algorithm and the international classical algorithm are combined to provide a more flexible safety solution. This hybrid approach can introduce post-quantum algorithms to address future security challenges while maintaining traditional algorithm compatibility.
A third hybrid algorithm based on the national cryptographic algorithm and the international classical algorithm, combined with the national cryptographic algorithm and the international classical algorithm, provides greater security and flexibility.
And a fourth hybrid algorithm based on a post quantum algorithm, a national cryptographic algorithm and an international classical algorithm is combined with the post quantum algorithm, the national cryptographic algorithm and the international classical algorithm to provide a more flexible safety solution. This hybrid approach can introduce post-quantum algorithms to address future security challenges while maintaining traditional algorithm compatibility.
By designing a plurality of preset algorithms, a user is allowed to select a proper algorithm according to actual demands, the whole process can be completed by using a classical algorithm under the condition that a certain party does not support a post quantum algorithm, and a comprehensive, flexible and prospective safety solution is provided for the user so as to protect data from being damaged by current and future potential threats.
In a second possible implementation, if the first VPN function module and the second VPN function module have already established a PQC secure channel, but want to replace the master key used, the secure channel can be re-established according to the following procedure, which saves the authentication procedure compared to re-establishing the secure channel.
Specifically, referring to fig. 3, establishing a PQC secure channel with a VPN server to negotiate a certain key and identity authentication includes:
Step S1011, transmitting the first random number, the session ID, the supported protocol version and the supported algorithm type to the VPN server, and receiving the second random number, the session ID, the selected protocol version and the selected algorithm transmitted by the VPN server to confirm that the first VPN function module and the VPN server communicate based on the same parameters.
Step S1013, a pre-master key and ciphertext of the pre-master key are packaged by using the first post-quantum algorithm public key, the pre-master key is reserved, the first random number, the second random number and the pre-master key are used for generating the master key, a session key is derived according to the master key, and then the ciphertext is sent to the VPN server.
Step S1014, after the ciphertext is decrypted by the VPN server, the session key is also generated by the VPN server, the client side and the VPN server mutually verify the session keys of the two parties, and after the session key is successfully verified, the client side uses the session key to carry out encrypted communication with the VPN server.
In a second aspect, the present invention provides an SSL VPN remote access system, including a client, a VPN server and a target server, where the client has an application, a first VPN function module and a first network interface that are sequentially connected by signals, the VPN server has a second network interface, a second VPN function module and a forwarding module that are sequentially connected by signals, and the target server has a plurality of service modules, where:
The application program sends the original data to the first VPN function module, the first VPN function module establishes a PQC secure channel with the second VPN function module to negotiate to determine a key, the first VPN function module encrypts the original data by using the negotiated encryption key, and the encrypted data is sent to the first network interface by the first VPN module.
After the second network interface receives the encrypted data sent by the first network interface, the encrypted data is transferred to the second VPN functional module, the second VPN functional module decrypts the encrypted data by using the negotiated decryption key and sends the decrypted data to the forwarding module, and the forwarding module forwards the decrypted data to the corresponding service module of the target server.
In the embodiment provided by the invention, the first VPN functional module and the second VPN functional module establish a PQC secure channel, which comprises the following steps:
The first VPN function module sends the first random number, the session ID, the supported protocol version, and the supported algorithm class to the second VPN function module.
The second VPN functional module selects a protocol version and an algorithm supported by the second VPN functional module from protocol versions and algorithm types supported by the first VPN functional module, and sends a selection result, a first post quantum algorithm public key, a second random number and a session ID to the first VPN functional module; the second VPN function module signs VPN server information by using a second postquantum algorithm private key to obtain a server signature, and the server signature is sent to the first VPN function module.
The first VPN function module uses a built-in second post quantum algorithm public key to verify the signature of the server, uses the first post quantum algorithm public key to package a premaster key and a ciphertext of the premaster key, reserves the premaster key, then sends the ciphertext to the VPN server, uses the first random number, the second random number and the premaster key to generate the master key, and derives a session key according to the master key.
The second VPN function module receives the ciphertext sent by the first VPN function module, decrypts the ciphertext by using the first post quantum algorithm key to obtain a premaster secret key, and generates a session secret key by using the first random number, the second random number and the premaster secret key.
The first VPN function module and the second VPN function module mutually authenticate a session key.
In a third aspect, embodiments of the present invention also provide an electronic device comprising a memory in which a computer program is stored and a processor arranged to run the computer program to implement the steps of any of the method embodiments described above.
Specifically, the electronic apparatus may further include a transmission device and an input/output device, where the transmission device is connected to the processor, and the input/output device is connected to the processor.
Specifically, in this embodiment, the above-mentioned processor may be configured to implement the following steps by a computer program:
step S101, a PQC secure channel is established with the VPN server to negotiate a certain key and identity authentication.
And step S102, encrypting the original data by using the negotiated encryption key, and transmitting the encrypted data to the VPN server.
And step S103, the encrypted data is decrypted by the VPN server by using the negotiated decryption key and then is sent to the target server.
In a fourth aspect, embodiments of the present invention further provide a storage medium having a computer program stored therein, wherein the computer program is arranged to implement the steps of any of the method embodiments described above when run.
Specifically, in the present embodiment, the above-described storage medium may be configured to store a computer program for realizing the steps of:
step S101, a PQC secure channel is established with the VPN server to negotiate a certain key and identity authentication.
And step S102, encrypting the original data by using the negotiated encryption key, and transmitting the encrypted data to the VPN server.
And step S103, the encrypted data is decrypted by the VPN server by using the negotiated decryption key and then is sent to the target server.
The construction, features and effects of the present invention have been described in detail with reference to the embodiments shown in the drawings, but the above description is only a preferred embodiment of the present invention, but the present invention is not limited to the embodiments shown in the drawings, all changes, or modifications to the teachings of the invention, which fall within the meaning and range of equivalents are intended to be embraced therein, are intended to be embraced therein.