Key management method and system

• US 9,705,672 B2
• Filed: 01/23/2014
• Issued: 07/11/2017
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: Fujian Landi Commercial Technology Company Limited
• Original Assignee: Fujian Landi Commercial Equipment Co., Ltd. (Ingenico Group SA)
• Inventors: Su, Wenlong, Meng, Luqiang, Yao, Chengyong, Chen, Ruibing
• Primary Examiner(s): Mehedi, Morshed
• Application Number:
  US14/775,633
• Publication Number:
  US 20160028539A1
• Time in Patent Office: 1,265 Days
• CPC Class Codes: H04L 2209/56 Financial cryptography, e.g. electronic payment or e-cash
• CPC Class Codes: H04L 63/062 for key distribution, e.g. centrally by trusted party cryptographic mechanisms or cryptographic arrangements for key distribution involving a central third party H04L9/0819
• CPC Class Codes: H04L 9/0825 using asymmetric-key encryption or public key infrastructure [PKI], e.g. key signature or public key certificates
• CPC Class Codes: H04L 9/0836 using tree structure or hierarchical structure
• CPC Class Codes: H04L 9/0861 Generation of secret information including derivation or calculation of cryptographic keys or passwords
• CPC Class Codes: H04L 9/0869 involving random numbers or seeds
• CPC Class Codes: H04L 9/32 including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials
• CPC Class Codes: H04L 9/3247 involving digital signatures
• CPC Class Codes: H04L 9/3265 using certificate chains, trees or paths; Hierarchical trust model

Abstract

Disclosed are a key management method and system. A master key is remotely downloaded to avoid the problem that the master key is not issued to a merchant until the master key needs be downloaded on a POS terminal, so as to reduce logistics costs and maintenance costs. When a key is remotely downloaded, a KMS system uses a symmetric algorithm to encrypt the key to be transmitted to ensure that the encrypted key can only be decrypted by a corresponding POS terminal, thereby ensuring the security of data transmission. During bidirectional authentication, an application program of the POS terminal can only contact an encrypted text form of the key instead of a plain text key needing to be remotely downloaded to the POS terminal, thereby ensuring security in reproduction.

Claims

1. A key management method, comprising:

calling a first hardware and security module to generate a public key Pu and a private key Pr, storing the private key Pr in the first hardware and security module and sending the public key Pu to a security module of the POS terminal, using a Material Tracking and Management (MTMS) system;

calling the first hardware and security module using the MTMS system and calling a second hardware and security module using a KMS system to respectively combine MTMS access components and KMS access components into a protective key PK and a MAC key MAK in the respective first and second hardware and security modules and store the protective key PK and the MAC key MAK in the respective first hardware and security module and the second hardware and security module;

using an operating terminal to generate a transmission key TK and store the transmission key in the security module of the POS terminal, wherein the transmission key TK consists of a transmission encryption key TEK and an authentication key AUK;

encrypting the transmission key TK using the public key Pu to generate a first transmission key cipher text Ctk_Pu in the security module of the POS terminal using the POS terminal;

sending the first transmission key cipher text Ctk_Pu and a terminal sequence number SN to the MTMS system through the operating terminal using the POS terminal;

storing the received terminal sequence number SN and the corresponding first transmission key cipher text Ctk_Pu in an SN-Key_MTMS database using the MTMS system;

calling the first hardware and security module to decrypt the first transmission key cipher text Ctk_Pu using the private key Pr to obtain the transmission key TK, encrypting the transmission key TK using the protective key PK and calculating a MAC value using the MAC key MAK to generate a second transmission key cipher text Ctk_Pk using the MTMS system;

sending the terminal sequence number SN and the second transmission key cipher text Ctk_Pk to the KMS system using the MTMS system;

storing the terminal sequence number SN and the second transmission key cipher text Ctk_Pk sent from the MTMS system in an SN-TK_KMS database using the KMS system;

sending the terminal sequence number SN and a downloading master key application to the KMS system using the POS terminal;

inquiring about the second transmission key cipher text Ctk_Pk corresponding to the terminal sequence number SN using the KMS system after receiving the terminal sequence number SN and the downloading master key application sent by the POS terminal;

calling the second hardware and security module to verify the MAC validity of the inquired-about second transmission key cipher text Ctk_Pk using the MAC key MAK, and if the verification is passed, decrypting the second transmission key cipher text Ctk_Pk using the protective key PK to obtain the transmission key TK, and storing the transmission key TK in the second hardware and security module, using the KMS system;

calling the second hardware and security module to perform bidirectional authentication using an authentication key AUK and the POS terminal by the KMS system after obtaining the transmission key TK, and if the authentication is passed, calling the second hardware and security module to encrypt the terminal master key TMK using the transmission decryption key TEK to generate a master key cipher text Ctmk, and sending the master key cipher text Ctmk to the POS terminal, using the KMS system;

decrypting the master key cipher text Ctmk using the transmission encryption key TEK to obtain the terminal master key TMK and storing the terminal master key TMK in the security module of the POS terminal, using the POS terminal after receiving the master key cipher text Ctmk sent by the KSM system.

2. The key management method according to claim 1, wherein the calling the first hardware and security module of the POS terminal to generate the public key Pu and the private key Pr, storing the private key Pr in the first hardware and security module and sending the public key Pu to the security module of the POS terminal, via the MTMS system comprises:

calling the first hardware and security module to generate the public key Pu and the private key Pr, storing the private key Pr in the first hardware and security module, recording an index number of the private key Pr in the first hardware and security module and sending the public key Pu to a CA center, via the MTMS system;

obtaining a generated working certificate HsmWCRT from the CA center and storing the working certificate in the SN-Key_MTMS database via the MTMS system, wherein the working certificate HsmWCRT is generated by signing the public key with a root certificate HsmRCRT;

obtaining a working certificate HsmWCRT from the SN-KEY_MTMS database of the MTMS system, and sending the working certificate HsmWCRT to the POS terminal, via an operating system;

verifying a validity of the working certificate HsmWCRT using a root certificate HsmRCRT preloaded in a record, by the POS terminal;

after the verification is passed, extracting the public key Pu and storing the public key Pu in the security module of the POS terminal, using the POS terminal.

3. The key management method according to claim 2, wherein the sending the first transmission key cipher text Ctk_Pu and the terminal sequence number SN to the MTMS system through the operating terminal by the POS terminal, and the storing the received terminal sequence number SN and the first transmission key cipher text Ctk_Pu in the SN-Key_MTMS database via the MTMS system comprises:

sending the first transmission key cipher text Ctk_Pu and the terminal sequence number SN to the operating terminal, via the POS terminal;

packaging the received first transmission key cipher text Ctk_Pu and the terminal sequence number SN, signing the first transmission key cipher text Ctk_Pu and the terminal sequence number SN with an operator card, and sending the signed first transmission key cipher text Ctk_Pu and the terminal sequence number SN to the MTMS system via the operating system;

verifying a validity of a signature, and if the signature is valid, storing the received terminal sequence number SN and the first transmission key cipher text Ctk_pu into the SN-TK_KMS database, via the MTMS system.

4. The key management method according to claim 3, further comprising extracting the terminal sequence number SN and the first transmission key cipher text Ctk_Pu to be sent from the SN-Key_MTMS database, verifying the validity of the signature, and if the signature is valid, executing the calling the first hardware and security module to decrypt the first transmission key cipher text Ctk_Pu using the private key Pr to obtain the transmission key TK, via the MTMS system.

5. The key management method according to claim 3, wherein the after obtaining the transmission key TK, calling the second hardware and security module to perform bidirectional authentication using the authentication key AUK and the POS terminal, using the KMS system comprises:

generating a first random number Rnd1 and sending the first random number Rnd1 to the KMS system using the POS terminal;

generating a second random number Rnd2, calling the second hardware and security module to encrypt the first random number using the authentication key AUK to obtain a first random number text Crnd1, and sending the first random number text Crnd1 and the second random number Rnd2 to the POS terminal using the KMS system after receiving the first random number Rnd1;

decrypting the received first random number text Crnd1 using the authentication key AUK to obtain a third random number Rnd1′

, and judging if the third random number Rnd1′

is consistent with the first random number Rnd1 or not, using the POS terminal;

if the third random number Rnd1′

is consistent with the first random number Rnd1, encrypting the second random number Rnd2 using the authentication key AUK to generate a second random number text Crnd2, and sending the second random number text Crnd2 to the KMS system using the POS terminal;

decrypting the received second random number text Crnd2 using the authentication key AUK to obtain a fourth random number Rnd2′

, and judging if the fourth random number Rnd′

is consistent with the second random number Rnd2 or not, via the KMS system;

and if the fourth random number Rnd′

is consistent with the second random number Rnd2, confirming the KMS system and the POS terminal pass the authentication.

6. A key management system, comprising a first hardware and security module, a second hardware and security module, an operating terminal, a POS terminal, a Material Tracking and Management (MTMS) system and a KMS system;

the first hardware and security module used to allow calls using the MTMS system, and the second hardware and security module used to allow calls using the KMS system;

wherein,

the MTMS is used for calling the first hardware and security module to generate a public key Pu and a private key Pr, storing the private key Pr in the first hardware and security module and sending the public key Pu to a security module of the POS terminal;

the MTMS system is used for calling the first hardware and security module and the KMS system is used for calling the second hardware and security module to respectively combine MTMS access components and KMS access components into a protective key PK and a MAC key MAK in the respective first and second hardware and security modules and store the protective key PK and the MAC key MAK in the respective first hardware and security module and the second hardware and security module;

the operating system is used for controlling the POS terminal to generate a transmission key TK and store the transmission key in the security module of the POS terminal, wherein the transmission key TK consists of a transmission encryption key TEK and an authentication key AUK;

the POS terminal is used for encrypting the transmission key TK by using the public key Pu in the security module of the POS terminal so as to generate a first transmission key cipher text Ctk_Pu, and sending the first transmission key cipher text Ctk_Pu and a terminal sequence number SN to the MTMS system through the operating terminal;

the MTMS system is used for storing the received terminal sequence number SN and the corresponding first transmission key cipher text Ctk_Pu in an SN-Key_MTMS database, and calling the first hardware and security module to decrypt the first transmission key cipher text Ctk_Pu by-using the private key Pr so as to obtain the transmission key TK, then encrypting the transmission key TK by using the protective key PK and calculating a MAC value using the MAC key MAK so as to generate a second transmission key cipher text Ctk_Pk, and sending the terminal sequence number SN and the second transmission key cipher text Ctk_Pk to the KMS system;

the KMS system is used to store the terminal sequence number SN and the corresponding second transmission key cipher text Ctk_pk sent by the MTMS system into an SN-TK_KMS database;

the POS terminal is used to send the terminal sequence number SN and a downloading master key application to the KMS system;

the KMS system is used to inquire about the second transmission key cipher text Ctk_Pk corresponding to the terminal sequence number SN after receiving the terminal sequence number SN and the downloading master key application sent by the POS terminal;

the KMS system is used to inquire about the second hardware and security module to verify a MAC validity of the inquired-about second transmission key cipher text Ctk_Pk by using the MAC key MAK, and if the verification is passed, decrypts the second transmission key cipher text Ctk_Pk using the protective key PK to obtain the transmission key TK, and store the transmission key in the second hardware and security module;

the KMS system is used for calling the second hardware and security module to perform bidirectional authentication by using the authentication key AUK and the POS terminal, and if the authentication is passed, the KMS system calls the second hardware and security module to encrypt a terminal master key TMK using the transmission decryption key TEK so as to generate a master key cipher text Ctmk and send the master key cipher text Ctmk to the POS terminal;

the POS terminal is used for decrypting the master key cipher text Ctmk using the transmission encryption key TEK to obtain the terminal master key TMK after receiving the master key cipher text Ctmk sent by the KSM system, and storing the terminal master key TMK in the security module of the POS terminal.

7. The key management system according claim 6, wherein the MTMS system is used for calling the first hardware and security module to generate the public key Pu and the private key Pr, storing the private key Pr in the first hardware and security module, recording an index number of the private key Pr in the first hardware and security module and sending the public key Pu to a CA center using the MTMS system;

the MTMS system is also used to obtain a generated working certificate HsmWCRT from the CA center and store the working certificate HsmWCRT in the SN-key_MTMS database;

the working certificate HsmWCRT is generated by signing the public key PU with a root certificate HsmRCRT;

the operating system is used to obtain the working certificate HsmWCRT from the SN-Key_MTMS database of the MTMS system, and send the working certificate HsmWCRT to the POS terminal;

the POS terminal is used to verify a validity of the working certificate HsmWCRT by using a root certificate HsmRCRT preloaded in a record, and used to extract the public key Pu after the verification is passed and store the public key Pu in the security module of the POS terminal.

8. The key management system according to claim 7, wherein:

the POS terminal is used to send the first transmission key cipher text Ctk_Pu and the terminal sequence number SN to the operating terminal;

the operating system packages the received first transmission key cipher text Ctk_Pu and the terminal sequence number SN, signs the first transmission key cipher text Ctk_Pu and the terminal sequence number SN with the operator card, and sends the signed first transmission key cipher text Ctk_Pu and the terminal sequence number SN to the MTMS system;

the MTMS system is used to verify a validity of a signature, and if the signature is valid, stores the received terminal sequence number SN and the corresponding first transmission key cipher text Ctk_pu into the SN-TK_KMS database.

9. The key management system according to claim 8, wherein:

the MTMS system is used for extracting the terminal sequence number SN and the first transmission key cipher text Ctk_Pu to be sent from the SN-Key_MTMS database, verifying the validity of the signature, and if the signature is valid, executing the step of calling the first hardware and security module using the MTMS system to decrypt the first transmission key cipher text Ctk_Pu by using the private key Pr so as to obtain the transmission key TK.

10. The key management system according to claim 8, wherein:

the POS terminal is used for generating a first random number Rnd1 and sending the first random number Rnd1 to the KMS system;

the KMS system is used for generating a second random number Rnd2 receiving the first random number Rnd1, calling the second hardware and security module to encrypt the first random number by using the authentication key AUK so as to obtain a first random number text Crnd1, and sending the first random number text Crnd1 and the second random number Rnd2 to the POS terminal;

the POS terminal is used for decrypting the received first random number text Crnd1 using the authentication key AUK to obtain a third random number Rnd1′

, and judging if the third random number Rnd1′

is consistent with the first random number Rnd1 or not;

the POS terminal is used for encrypting the second random number Rnd2 using the authentication key AUK to generate a second random number text Crnd2, and sending the second random number text Crnd2 to the KMS system, when judging that the third random number Rnd1′

is consistent with the first random number Rnd1;

the KMS system is used for decrypting the received second random number text Crnd2 using the authentication key AUK so as to obtain a fourth random number Rnd2′

, and judging if the fourth random number Rnd′

is consistent with the second random number Rnd2 or not;

and the KMS system is used for confirming that the KMS system and the POS terminal pass the authentication when judging that the fourth random number Rnd′

is consistent with the second random number Rnd2.