Design and Implementation of a Secure Scheme for the C/S mode E-Government system

Zhihui. Feng School of Information and Management Science

Henan Agricultural University ZhengZhou, China fzhh@henau.edu.cn

Yanjie.ZhuSchool of Economics and Management

XuChang University XuChang, China

zyj_2006@126.com

Abstract—This paper introduces the application of the security policy and technology based on the PKI in E-government. The signatures and certification process module based on C/S model PKI security application is designed from the point of view of E-government applications; it emphasizes the solution of SSL VPN found on Security Gateway for E-government in order to implement the security of application platform and data.

Keywords-Digital Certificate; Authentication; E-Government

I. INTRODUCTION

Public Key Infrastructure PKI [1] is a kind of new safety technology system, which consists of public-key cipher technology, digital certificate, certificate authority and the security strategy about Public Key. PKI uses certificate to manage Public Key bind public key and the other identification information to verify user identity through third-party authentication center [2]. The public key infrastructure combines public key cryptography and symmetric cryptography, realizes automatic management of key on the Internet, and guarantees the security of data transmission online.

The realization of E-government is dependent on the computer technology and network technology, so safety hidden trouble exists unavoidably in E-government, such as identity authentication and information of confidentiality and integrity, non-repudiation etc[2].In order to eliminate the safety issues, guarantee the smooth implementation of e-government, the application of security PKI technology ensures the information transmission process information confidentiality and integrity, provides the digital signature to confirm non-repudiation of online behavior, and prevents all kinds of electronic government affair safety hazard eventually.

The functions such as access control and file encryption preservation are realized in PKI security applications. The personnel have different permissions when they browse information, in order to prevent the government internal staff stealing sensitive personal or enterprise information; The files of local computer cannot be opened by others.PKI is the security mechanism of five data security requirements, completely supports with identity authentication, material non-repudiation, data integrity, information confidentiality access control[3].

II. DIGITAL CERTIFICATE

A. The Identity Authentication Digital signature can solve denied, forgery, tampering and

imitation. Its requirements: the sender cannot deny verifying the signature after sending a message, the receiver cannot forge the signature of senders and tamper any message of sender, and one user in the Internet doesn't pretend to be another as the sender or receiver. Digital signature is wide range in information security. Electronic Data Interchange (EDI) security is a breakthrough progress, which uses digital signature when requiring the user identity judgment situation, such as encryption letter, business letters, ordering and purchasing system, distance financial transactions, automatic mode processing etc. Encrypting data and signature through a digital certificate ensure confidentiality, integrity and non-repudiation of data in the information transmission process.

B. Role-Based Access Control Strategy It is the main advantage of the identity authentication for

PKI. For all application systems, we can create a unity system authentication platform, when logging in any application system; users are authenticated by the same backend authentication database server based on digital certificate authentication. After a user has passed the authentication, he can access to any application system without identity authentication. When the user who has passed authentication operates an application system, the system distinguishes user's identity by digital certificate and gives the user permissions access according to the user's own level. Whenever the user want to access to the other system, user should be authorized by the system; Authentication once and multiple authorization can effectively achieve the authentication management based on user role.

Information management system is a large distributed management system about data resource; it consists of a lot of information and different information sensitivity. Because of various access requirements of users, it is very complex for authentication management. Its characteristic is user’s permissions granted or canceled through the role distribution and cancellation, and the operating rules provided and rules distribution of role. It defines various roles and sets the right of access to for safety manager based on need. And users are

Sponsor: Henan province higher education informatization projects.

2010 Second International Workshop on Education Technology and Computer Science

978-0-7695-3987-4/10 $26.00 © 2010 IEEE

DOI 10.1109/ETCS.2010.106

539

appointed as different roles according to their responsibilities and qualifications. So, the access control process includes two parts: access permission associated with role, role associated with user, and access permission independent of the user. Role which is regard as semantic structure of an access control strategy can be said for qualifications of specific control [4].

Because of access permission separated from the user, it is a great convenience to manage permission through the role. For example, if a user's position is changed, it removes the role of the user and adds new duties or new mission role. Research shows that the change between the role and privileges is slower than between role and customer; assigning a role to the user can be easily executed by the administrative personnel. Because of complexity of configuring permission of role, it can be done by the special technical personnel, but don't give them the user permissions. Role-based access control method can be very good to describe the hierarchical relationships and realizes least permission principle and roles and responsibilities of separation principle besides convenient access management.

III. DESIGN OF PKI BASED ON C/S MODE

C/S system is connected with user management center, in order to prevent illegal users from entering the system. Using authentication certificate to confirm the legitimate user login is a more effective protective measure for the whole data security. User authentication is achieved by signature verification, as shown in Fig. 1.

Figure 1. Flow of signature verification

Authentication Center issues user certificate to release directory server, and saves private key and certificate in USB Key before giving it user.

When each time entering the server, user needs a USB Key with private-key. Signature module generates a random signs, and reads the certificate and private-key from USB key. After random information has been signed, the certificate, the original information and the information signed are sent to the server. Signature module is shown in Fig. 2.

Figure 2. Signature module

Original application system should be adjusted while using signature authentification based on certificate. Developers of the system should open the corresponding API interfaces for the development of authentication module of signature and give appropriate modification of old authentication setup.

According to the certificate, the original information and the information signed from client, authentication module of server connects release LDAP directory server [5]. If the certificate is in the certificate revocation list of LDAP, the authentication failed; otherwise, using local CA root certificate to confirm validity of user’s certificate, if available, reading the public key of user to authenticate information signed. Signature certification is verified by passing authentication. If the authentication fails, the user is disconnected and cannot login. Only the user with legitimate certificate can enter system through authentication certificate. Authentication module is shown in Fig. 3.

Figure 3. Authentication module

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IV. IMPLEMENT OF PKI BASED ON C/S MODE

Accessing a variety of applications in the network, two-way authentication, access control and data transmission encryption between user and server are achieved for the purpose of system date safety. SSL VPN is built by secure gateway, its following features:

Security gateway based on SSL protocol, digital certificate technology and high-strength encryption algorithms can meet remote access security requirements of network environment and guarantee access data security.

Security gateway with USB Key (hardware store digital certificates medium) uses two factors (the certificate and password) to provide authentication; Gateway based on user roles realizes the back-end server resources access control, and provides the high-speed access SSL encrypted tunnel in the whole process, so as to a guarantee of the back-end resources in a variety of application server security. The SSL VPN scheme based on security gateway is shown in Fig. 4.

CISCOSYSTEMS

Figure 4. The SSL VPN scheme based on security gateway

The SSL VPN scheme based on security gateway logic diagram is shown in Fig. 5.

Figure 5. The SSL VPN logical diagram of security gateway

The specific steps of SSL VPN solution based on Security Gateway are as follows: First, SSL client program enabled gets the certificate information from USB-Key. Certificate information will be sent to the user SSL security gateway by SSL client. After received the appropriate user certificate information, SSL gateway connects the external directory server; Server checks user’s certificates before building secure SSL connection between clients. The user's request is sent to SSL gateway through SSL encrypted channel in Socks proxy mode by SSL client. According to the built-in RBAC, SSL gateway determines whether the user's application request is within its competence. If passed, requests of user are transmitted to the corresponding server. Data communication between Users and the application servers is protected by SSL encryption. At any time, so long as user unplugs the USB-Key, the connection immediately interrupts. It ensures that only legitimate users can access the resources within their purview.

The compatibility of network application systems is given full consideration; Access control, secure authentication, secure communications and a series of security measures are completely achieved for E-government system in the application layer.

ACKNOWLEDGMENT

We would like to express our gratitude to the reviewers for their comments and suggestions to this paper. We thank ETCS2010 Organizing Committee which made this International Workshop possible.

REFERENCES

[1] RSA Laboratories,Understand Public Key Infrastructure, RSA Security Inc, 1999.

[2] N. Li and Y. H. Wu, “ Mutual Authenticate Framework Based on x.509,” Computer Application and Engineering, vol. 41, no.18, 2005, pp.10-11.

[3] F. B. Zhang and C. H. Zhang, “Application of Secure E-government Based on PKI,”Computer Engineering,vol. 30, no. 6, 2004, pp.130-132.

[4] Z. X. Gao, Y. Q. TU and Z. X. LI,“Design and Implementation of PKI and RBAC-authorized Digital Certificate,” Computer Engineering, vol. 34, no. 2, 2008, pp.117-119.

[5] LuZhengtian,“Design and Implementation of a Secure E-Government System,” Information Security and Communications Privacy, vol. 28, no. 3, 2006, pp. 58-60.

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