198 results about "Key escrow" patented technology

A secure method for sending registered, authenticated electronic documents. The invention validates sender and recipient identities, provides for non-repudiation of authenticated documents by sender and recipient, provides an evidence trail, and protects the integrity of the document. The invention is constructed so that a sender can be supplied with proof that the intended recipient received and opened an authenticated document. A neutral third party acts as a document registration agent, and witness to the transmission and receipt of the authenticated document. In the event of a dispute between sender and recipient, the third party can provide an irrefutable record of the contents of the document and of the history of the transmission and receipt of the document Because the third party never has possession of the electronic document, the method provides maximum privacy for sender and recipient. The method is readily adaptable to both key recovery and key escrow.

Embodiments are directed to allowing a user to store encrypted, third-party-accessible data in a data store and to providing third party data access to a user's encrypted data according to a predefined policy. A data storage system receives encrypted data from a user at a data storage system. The data is encrypted using the user's private key. The data storage system stores the received encrypted data according to a predefined policy. The encryption prevents the storage system from gaining access to the encrypted data, while the policy allows the encrypted data to be released upon receiving a threshold number of requests from verified third parties. The data storage system implements a verifiable secret sharing scheme to verify that the encrypted data can be reconstituted without the data storage system accessing the encrypted data. The data storage system synchronously acknowledges that the received encrypted data has been verified and successfully stored.

A method is provided for an escrow cryptosystem that is essentially overhead-free, does not require a cryptographic tamper-proof hardware implementation (i.e., can be done in software), is publicly verifiable, and cannot be used subliminally to enable a shadow public key system. A shadow public key system is an unescrowed public key system that is publicly displayed in a covert fashion. The keys generated by the method are auto-recoverable and auto-certifiable (abbrev. ARC). The ARC Cryptosystem is based on a key generation mechanism that outputs a public/private key pair, and a certificate of proof that the key is recoverable by the escrow authorities. Each generated public/private key pair can be verified efficiently to be escrowed properly by anyone. The verification procedure does not use the private key. Hence, the general public has an efficient way of making sure that any given individual's private key is escrowed properly, and the trusted authorities will be able to access the private key if needed. Since the verification can be performed by anyone, there is no need for a special trusted entity, known in the art as a "trusted third party". The proof and verification method involves one party proving to a second party that a third party can gain access to an encrypted value. In addition, the system is designed so that its internals can be made publicly scrutinizable (e.g., it can be distributed in source code form). This differs from many schemes which require that the escrowing device be tamper-proof hardware. The system is efficient and can be implemented as a "drop-in" replacement to an RSA or ElGamal cryptosystem. The system is applicable for lawenforcement, file systems, e-mail systems, certified e-mail systems, and any scenario in which public key cryptography can be employed and where private keys or information encrypted under public keys need to be recoverable. The system security relies solely on the security of cipher systems involved whose security has been extensively studied in the past.

The invention discloses a distributed aggregation authentication method having a privacy protection function for a vehicle-mounted self-organizing network. The method comprises the following steps: a step of trusted root mechanism arrangement, a step of road side unit arrangement, a step of vehicle arrangement, a step of internal pseudonym and authentication key updating, a step of a vehicle obtaining secrets of members and authorization terms, a step of the vehicle generating signatures and updating the secrets of the members, a step of tracking and a step of message verification and information storage. The distributed aggregation authentication method is characterized in that conditional privacy is not associable, the method is independent of an ideal and strict anti osmosis device, and no secret key trusteeship problem can be caused. Safe and private communication of a the vehicle-mounted self-organizing network can be realized through the distributed aggregation authentication method.

The invention provides a partial key escrow (PKE) method and system based on a public key cryptographic algorithm SM2, and belongs to the field of information security. N (N is not less than 1) different PKE systems form one key escrow network. An SM2 private key of a user is divided into N+1 partial keys by utilizing key partition storage and multiparty combined calculation modes; the user and the N different PKE systems perform scatter storage; and the user and the N different PKE systems are combined to complete a correlation calculation when the private key needs to be used. At user key generation and use stages, the PKE system generates user partial private keys by utilizing a labeling mapping algorithm, but does not practically save the user partial private keys; therefore, the construction scale of the system can be largely reduced, investment costs of the system are reduced, and operation efficiency and service level of the system are improved.

The invention relates to a key escrow-free secure multi-keyword sorting and searching system. The system comprises a key generation center, a cloud server, a data owner and a data user; the key generation center is used for achieving interactive computing with the cloud server to jointly generate a public parameter of the system and a property public key-private key pair of the data user; the cloud server is used for storing a file of the data owner and responding to a searching query request of the data user; the data owner extracts a keyword set from the file, encrypts the keyword set into asecure index, encrypts the file, makes an access strategy and embeds the access strategy into ciphertext; and the data user defines the searched keyword set and generates a trap door by using the property private key of the data user to search for the encrypted file stored in the cloud server. According to the system, the key escrow problem is solved, flexible authorization keyword searching andfine-grained data access authorization are achieved, multi-keyword subset searching is supported, and the searching result is not influenced by changes of the keyword query order.

The invention relates to the technical field of data encryption in information security, and discloses a certificate-based agent heavy encryption method and system, for solving the defect of a conventional agent heavy encryption method. The invention provides a certificate-based agent heavy encryption method by combining a certificate password system and agent heavy encryption. The method comprises the steps of generating system parameters, generating a user public key and private key pair, generating a user certificate, encrypting messages, generating agent heavy encryption secret key, agent heavy encrypting and message recovery. The invention also provides a certificate-based agent heavy encryption system. The system comprises a system parameter generation module, a user secret key generation module, a certificate generation module, an encryption module, an agent heavy encryption secret key generation module, an agent heavy encryption module and a decryption module. The technical scheme provided by the invention not only simplifies a certificate management process, but also eliminates the problems of secret key distribution and secret key hosting and facilitates application in open network environment.

An embodiment pertains generally to a method of storing keys. The method includes receiving a request for generating a subject private key at a token processing system and generating a subject key pair, where the subject key pair includes a subject public and the subject private key. The method also includes archiving the subject private key within the token processing system.

The present invention discloses a identity-based authentication group key management method which comprises the following steps: embedding ID into key with bilinear pairing in elliptic curve; generating Ci as part of main key ui according to the secret key and ID of group member ui by key generating center, and transmitting the Ci to ui through overt channel; generating main key according to Ci and its own secret key by each group member ui; calculating overt key verification information according to Hash value of main key and over key by each group member, and broadcasting the link between over key and verification information inside the group; calculating the secret value sharing with left and right neighbors when the received information is verified to be true by each group member, and calculating the group member information Xi included in group session key according to the secret value, and then broadcasting the Xi inside the group; calculating group session key K according to all Xj, j=1, ...,n, by each group member. The invention has the advantages of no key escrow and no need of secure channel, which can be applied in coordination and distributed network as secure reliable group communication.

This invention relates to a negotiation method and a system for both party certificated cryptographic keys based on hidden public key certificates, which applies three stages of system initialization, user end registration, generation of hidden public key certificates and distribution and certificated cryptographic key negotiations to utilize the traditional cipher plan of PKI and identity base to eliminate unnecessary trusteeship of the cryptographic keys on one hand and keep the advantages of part of identity base ciphers on the other, besides, this invention also discloses a system for realizing negotiation method of both party certified keys based on hidden public key certificates.

The invention provides for robust efficient distributed generation of RSA keys. An efficient protocol is one which is independent of the primality test "circuit size", while a robust protocol allows correct completion even in the presence of a minority of arbitrarily misbehaving malicious parties. The disclosed protocol is secure against any minority of malicious parties (which is optimal). The disclosed method is useful in establishing sensitive distributed cryptographic function sharing services (certification authorities, signature schemes with distributed trust, and key escrow authorities), as well as other applications besides RSA (namely: composite ElGamal, identification schemes, simultaneous bit exchange, etc.). The disclosed method can be combined with proactive function sharing techniques to establish the first efficient, optimal-resilience, robust and proactively-secure RSA-based distributed trust services where the key is never entrusted to a single entity (i.e., distributed trust totally "from scratch"). The disclosed method involves new efficient "robustness assurance techniques" which guarantee "correct computations" by mutually distrusting parties with malicious minority.

The invention relates to a public key cryptosystem private key escrow system based on identification. A client cryptosystem transmits the information of a user to a private key generator for requesting authentication; a user private key is generated and stored at the client cryptosystem after the authentication of the private key generator is passed; and the client cryptosystem provides an operation interface for an application program, and realizes the cryptographic operation internally. The public key cryptosystem private key escrow system dynamically acquires the private key form the private key generator when a user is logged in, a tamper-proofing authentication protocol and the technology of a cipher device can ensure the user to acquire the private key safely. Because the user neither stores the private key statically nor dynamically exposes the private key out of the cipher device, so the hacking difficulty of a hacker is increased. The public key cryptosystem private key escrow system can effectively resist various dynamic and static analysis methods.

The invention discloses an internet of vehicles conditional privacy protection method and system based on certificateless aggregation signature. The internet of vehicles conditional privacy protection method based on certificateless aggregation signature is provided based on a certificateless cryptosystem. On the basis of internet of vehicle conditional privacy protection of a traditional public key cryptosystem, an aggregation signer aggregates various different signatures into one signature, the internet of vehicles conditional privacy protection scheme is realized by employing a key generation center KGC and a tracking authentication center TRA, the problems of certificate management and key hosting are avoided, the computing efficiency of an internet of vehicles is improved when the aggregation signature is authenticated, the conditional privacy protection of internet of vehicles users is realized, and the method and the system can be applied in the open internet of vehicles safely.

This invention discloses a multi-receiver signcryption method based on keyless trusteeship problem of elliptic curve, and solves the technical problem of private key trusteeship existed in the existing multi-receiver signcryption method. The method comprises the following steps: a user randomly selects a secret value as own private key, calculates a verification share according to own private key, and sends the verification share and own identity information to a private key generating center KGC; the private key generating center KGC generates a public key, a public key verification parameter and a public key hiding parameter of the user according to the verification share and the identity information sent by the user, and sends the public key, the public key verification parameter and the public key hiding parameter to the user; and after receiving the parameters sent by the private key generating center KGC, the user verifies the public key. Since the private key of the user is the secret value randomly selected by the user, the private key generating center KGC only knows the public key and corresponding identity information of the user, and cannot acquire the private key of the user to realize keyless trusteeship. Simultaneously, the signcryption efficiency is improved; and the bandwidth is reduced.

The invention discloses an efficient certificateless signature method based on an elliptic curve discrete logarithm problem. The method has the advantages of a common certificateless signature algorithm, namely a certificate management problem of a traditional public key system and a key escrow problem in an identity password system are eliminated; and the algorithm is simple in calculation process, and time-consuming bilinear operation does not need to use. The algorithm can be efficiently applied to fields such as e-commerce and the like of requiring the electronic signature.

The invention discloses a multifunctional fine-grained access control method for cloud storage, and solves the problem of fine-grained access control of data in cloud storage. The implementation stepsof the method are as follows: performing global initialization and attribute organization initialization; generating the public and private keys of a user and a private key of a cloud server; enabling a system to perform offline/online encryption, wherein the system is provided with a strategy hiding mechanism; uploading a final ciphertext to the cloud server; enabling the cloud server and a userterminal to decrypt and verify the correctness of the keys; enabling the cloud server to delete the corresponding entry from a key list for user revocation. The invention proposes a multi-system CP-ABE scheme with multiple characteristics, and the offline/online encryption mechanism is constructed in detail, which greatly reduces the computational cost of the user. The method has the functions ofattribute revocation, keyless collocation problem, the offline/online encryption mechanism, the strategy hiding and verifiability, and can be applied to fine-grained access control of data in cloud environments such as education, business and medical fields.

The invention discloses a certificate-free anonymous authentication method for a wireless body area network, which mainly solves the anonymity problem of wireless body area network remote authentication, and mainly comprises the steps as follows: 1) a network manager initializes a whole wireless body area network system; 2) a wireless body area network user carries out identity register from the network manager; 3) the network manager issues an account index to the wireless body area network user; 4) the wireless body area network user uses the account index to disguisedly send a service request to the network manager; and 5) bidirectional authentication between an application service provider and the wireless body area network user is achieved. According to the invention, a certificate is not required, the defect of no key escrow is avoided, the security performance is high, the degree of complexity of calculation is low, and the method can be used for remote medical treatment monitoring and on other application occasions.

The invention relates to a certificateless partially blind signature method. In the prior art, practicality of the partially blind signature method is low. The method of the invention is mainly used to solve the above problem. The method comprises the following steps that: 1) a secret key generation center randomly selects an integer sPKG as a private key in an integer multiplication group of mod q and stores secretly, and discloses a system parameter: (G1, q, 1, P, G2, e, H, h, QPKG); 2) a signer generates the partial private key s1 and a partial public key Q1, the secret key generation center generates the other partial private key S2 and the public key Q2 and sends to the signer through a safe authentication channel, and the signer acquires a private key pair (s1, S2) and a public key pair (Q1, Q2); 3) the signer carries out signature; 4) an authenticator verifies validity of the signature by using the public key pair (Q1, Q2) of the signer. By using the method of the invention, a demand to a certificate can be eliminated. There is no disadvantage of secret key escrow. A partial blind characteristic is possessed. Simultaneously, the method is simple and high efficient and possesses good practicality and security. The method can be used in an electronic cash transaction and electronic voting.

The present invention discloses a method and system for certificating a vehicle identity, and belongs to the field of mobile communication. The method includes: a road side unit RSU certificates an agent vehicle and acquires a session key of the agent vehicle when the certification is passed; the agent vehicle constitutes a vehicle group, and receives second information sent by vehicles within the RSU communication scope; the second information is sent to the RSU after encrypted using the session key of the agent vehicle, so that the RSU certificates the vehicles in the RSU communication scope in a batch according to the second information; and the RSU sends a false identity identification of the vehicle which does not pass the certification within the RSU communication scope to the vehicles in the RSU communication scope. The system includes: an acquiring module, a sending module, a certification module, a generating module and an encryption module. The present invention acquires a private key of the agent vehicle through the agent vehicle, which avoids the problem of secret key hosting; moreover, the RSU sends the false identity identification of the vehicle which does not pass the certification to the vehicles in the RSU communication scope, which considers revocation for illegal vehicles.

Embodiments described herein relate to apparatuses and methods for registering and storing a local key associated with a local application of a communication device, including, but not limited to, receiving a request from the communication device to register and store the local key, evaluating the request based on at least one first policy, and sending the request to register and store the local key to a secure key storage.

A variant on the "One Time Pad' cipher is used to provide an encrypted link between two or more stations. The main feature of this variant is the use of a unique and easily created Pseudo-Random Number Sequence segment not having any internal repeats. At one station, a mixing function is used to combine a locally created stream of truly random bytes with a portion of this unique PRNS segment, yielding a fresh stream of truly random data. This freshly created stream of truly random data is operated on in such a way as to create a new and unique PRNS element set which is used to control the functioning of a PRNS generator. The PRNS generator is used to create a new and unique PRNS segment which has a repeat period much longer than the length of the PRNS element set used to create it. It is then useful to treat the PRNS element set as a message and transfer it across the encrypted link to other stations. In this fashion, this OTP cipher variant can be re-keyed and used for as long as there is a continuing source of truly random data available at one of the stations on the network. This technique of using unique and freshly created PRNS segments rather than the classic One Time Pad allows encrypted networks to function independently of any central key distribution regimens or Public Key Infrastructures, making such an encrypted network proof against security breaches perpetrated upon, or key escrow schemes propagated through, such external key distribution infrastructures. This technique also provides certain securities against willful betrayals by tempted users or coerced revelations by users under duress.