Electronic Business: Concepts, Methodologies, Tools, and Applications (4-Volumes) P220 pps

2124 Web Services Security in E-Business SOAP M essage 1 SOAP M essage 2 SOAP M essage n Attacker Web Service )LJXUH62$3PHVVDJHVÀRRGLQJ Initial Sender Intermediary Ultimate Receiver Figure 6. A SOAP message routes via an intermediary Malicious Location Ultimate Receiver Compromised Intermediary Initial Sender Figure 7. Compromised intermediary route a SOAP message to a malicious location GUHVVWKHLVVXHRIGDWDFRQ¿GHQWLDOLW\DQGLQWHJULW\ UHVSHFWLYHO\+RZHYHUWKHVHWZRVSHFL¿FDWLRQV do not specify implementation issues of SOAP PHVVDJHVLQWHJULW\DQGFRQ¿GHQWLDOLW\7KLVSDUW is covered by additional standard that has been GH¿QHG LQ 1DGDOLQ .DOHU +DOODP%DNHU DQG 0RQ]LOOR7KHGHWDLORIHDFKVSHFL¿FDWLRQ is described as follows: • XML encryption: 7KH ;0/ HQFU\S- WLRQ V\QWD[ DQG SURFHVVLQJ VSHFL¿FDWLRQ describes the processing rules for encrypt- ing/decrypting data (Eastlake & Reagle,  7KLV VSHFL¿FDWLRQ DOVR GH¿QHV WKH V\ QWD[WKDWUHSUHVHQWVWKHHQFU \SWHGGDWDL Q ;0/IRUPDW;0/HQFU\SWLRQVXSSRUWVWKH encryption of arbitrary data (including an 2125 Web Services Security in E-Business ;0/GRFXPHQWDQ;0/HOHPHQWRU;0/ HOHPHQWFRQWHQW7KHIROORZLQJH[DPSOHLO- lustrates how to keep sensitive information FRQ¿GHQWLDOE\HQFU\SWLQJDQ;0/HOHPHQW (Eastlake & Reagle, 2002). Listing 5 shows the payment information that contains credit FDUGQXPEHULQFOHDUWH[WIRUPDWZKLOH/LVW- ing 6 shows the entire CreditCard element is encrypted from its start to end tags. An eavesdropper does not know any sensitive LQIRUPDWLRQFRQWDLQHGLQWKLV;0/GRFX- ment. The CreditCard element is encrypted using TripleDES algorithm in cipher block FKDLQLQJ&%&PRGHZKLFKLVVSHFL¿HG by the EncryptionMethod element. The resulting encrypted data is contained in the CipherValue element. • XML signature:7KH;0 /VLJQDW X UHV\ Q- WD[ DQG SURFHVVLQJ VSHFL¿FDWLRQ SURYLGHV the security services in terms of data integ- rity, message authentication, and/or signer authentication (Eastlake et al., 2002). This VSHFL¿FDWLRQ GH¿QHV WKH SURFHVVLQJ UXOHV IRUFUHDW LQJDQGYHU LI \LQJ; 0/VLJQDWX UHV ,WDOVRLQFOXGHVWKHV\QWD[IRUUHSUHVHQWLQJ the resulting signature information. Listing LVDQH[DPSOHRI;0/VLJQDWXUH(DVW- lake et al., 2002). The signature algorithm for signing the document is DSA, which is VSHFL¿HGLQWKHSignatureMethod element, while the DigestMethodHOHPHQWVSHFL¿HV the digest algorithm (i.e., SHA-1 in this case) applied to the signed object. The resulting digital signature value and digest value are HQFRGHGXVLQJEDVHDQGVSHFL¿HGLQWKH SignatureValue element and the DigestValue element respectively. • Web service security: SOAP message security: 7KLVLVDVSHFL¿FDWLRQGHYHORSHG by the Organization for the Advancement of Structured Information Standards (OASIS). 7KLV VSHFL¿FDWLRQ GH¿QHV D VHW RI 62$3 H[WHQVLRQVWRSURYLGHWKHVXSSRUWRIPHV- VDJHLQWHJULW\DQGFRQ¿GHQWLDOLW\1DGDOLQ HWDO7KHVSHFL¿FDWLRQLVÀH[LEOHDQG can be accommodated to various security models such as PKI, Kerberos, and SSL. Authentication and Authorization Authentication in e-business is the process to validate the identities of business entities, while authorization is a process to determine an authen- ticated party can access what sort of resources RUSHUIRUPZKDWNLQGRIDFWLRQV)RUH[DPSOH RQO\ VSHFL¿F DXWKHQWLFDWHG EXVLQHVV SDUWQHUV Initial Sender NoQH[Lstent Destination Compromised Intermediary Ultimate Receiver Initial Sender Figure 8. Compromised intermediary route a SOAP message to a nonexistent destination 2126 Web Services Security in E-Business should be able to access sensitive information. In general, access control rules are created to apply WKHUHVWULFWLRQWRVSHFL¿FFRQWHQWVRUDSSOLFDWLRQ I X Q F W LR Q D O LW \ 7 K H I RO ORZ L QJ V S HF L ¿F D W LR Q VV K R X O G  be applied in the Web service architecture to ensure these security goals. • Security assertion markup language (SAML): This specification defines a IUDPHZRUN IRU H[FKDQJLQJ DXWKHQWLFDWLRQ and authorization information between e- business partners (Cantor, Kemp, Philpott, & M a l e r, 2 0 05 ). S A M L s u p p o r t s s i n g le s i g n - RQ662IRUDI¿OLDWHGVLWHV%DVLF6$0/ components include assertions, protocols, EL Q G L QJ V  D QGS U R¿ O H V 7 KH U H D UH W K U H H W \ S H V  of assertions: authentication, attribute, and authorization. The authentication statements contain authenticated related information of a user. The attribute statements describe VSHFL¿F GHWDLOV DERXW WKH XVHU ZKLOH WKH authorization statements identify what the user is permitted to do. There is a set of request/response protocols for obtaining DVVHUWLRQV7KHELQGLQJVGH¿QHKRZ6$0/ protocols map onto the transport protocol, VXFKDV+773ZKLOHWKHSUR¿OHVGH¿QHKRZ SAML assertions, protocols, and bindings are combined for a particular use case. • XML access control markup language (XACML): 7KLV VSHFL¿FDWLRQ SURYLGHV D FRPPRQ ODQJXDJH IRU H[SUHVVLQJ DFFHVV FRQWUROSROLFLHVLQ;0/YRFDEXODU\0RVHV ,WGH¿QHVWKHPHFKDQLVPIRUFUHDWLQJ <?[Pl version='1.0'?> <PaymentInfo[mlns='http://e[Dmple.org/paymentv2'> <Name>John Smith</Name> <CreditCard Limit='5,000' Currency='USD'> <Number>4019 2445 0277 5567</Number> <Issuer>([ample Bank</Issuer> ([Siration>([Siration> </CreditCard> </PaymentInfo> <?[Pl version='1.0'?> <PaymentInfo[mlns='http://e[Dmple.org/paymentv2'> <Name>John Smith</Name> <EncryptedDaWD[mlns='http://www.w3.org/[Plenc#' Type='http://www.w3.org/[Plenc#Element'/> <EncryptionMethod Algorithm='http://www.w3.org/200[mlenc#tripledes-cbc'/> <ds:KeyInfo [Plns:ds='http://www.w3.org/2000/09/[Pldsig#'> <ds:KeyName>John Smith</ ds:KeyNam e> </ds:KeyInfo> <CipherData><CipherValue>DEADBEEF</CipherValue></CipherData> </EncryptedData> </PaymentInfo> Listing 5. Simple payment information (Source: W3C) Listing 6. Encrypting an XML element (Source: W3C) 2127 Web Services Security in E-Business the rules and policy sets that determine what users can access over a network. • Access control for SOAP messages: It is important to apply a security mechanism such as access control to SOAP messages. D a m i a n i , D e C a p i t a n i d i Vi m e r c a t i , P a r a b o s - chi, and Samarati (2001, 2002) have proposed DZRUNRQ ¿QHJUDLQHGDFFHVVFRQWUROIRU SOAP e-services. The authorization model enforces access restrictions to SOAP invo- FDWLRQV7KHUHLVDQDXWKRUL]DWLRQ¿OWHUWR intercept every SOAP message and evaluates LWDJDLQVWWKHVSHFL¿HGDFFHVVFRQWUROUXOHV Based on the policies, each soap message may (1) be rejected; (2) be allowed; or (3) be ¿OWHUHGDQGH[HFXWHGLQDPRGL¿HGIRUP Audit Trails Audit trails are also an important security re- quirement in Web services architecture (Booth, et. al., 2004). They can audit the activities for the Web services architecture such as changes in DQ\FRQ¿JXUDWLRQ2QWKHRWKHUKDQGWKH\PD\ provide audit on a business level. All the Web service transactions can be recorded as a proof of the business transaction occurred. In addition, they can support, for tracing, user access and behavior when there is any security breach. The audit trails may also provide as data sources for an intrusion detection system in the Web services environment. Intrusion Detection and Prevention $OPRVWHYHU\RUJDQL]DWLRQDOORZVQHWZRUNWUDI¿F pass through port 80 or 443 to access Web ap- SOLFDWLRQV$VVXFKWUDGLWLRQDOQHWZRUN¿UHZDOOV do not block most of the SOAP messages that transport via HTTP (port 80) or HTTPS (port 443). In addition, they do not check if there are a n y m a l ic i o u s c o n t e n t s i n t h e S OA P m e s s a g e s . A s <Signature Id="MyFirstSignature"[mlns="http://www.w3.org/[Pldsig#"> <SignedInfo> <CanonicalizationMethod Algorithm="http://www.w3.org/TR/2001/REC-[Pl-c14n-20010315"/> <SignatureMethod Algorithm="http://www.w3.org/[Pldsig#dsa-sha1"/> <Reference URI="http://www.w3.org/TR/2000/R(&[html1-20000126/"> <Transforms> <Transform Algorithm="http://www.w3.org/TR/2001/REC-[Pl-c14n-20010315"/> </Transforms> <DigestMethod Algorithm="http://www.w3.org[Pldsig#sha1"/> <DigestValue>j6lZ[3rvEPO0vKtMup4NbeVu8nk=</DigestValue> </Reference> </SignedInfo> <SignatureValue>MC0CFFrVLtRlk= </SignatureValue> <KeyInfo> <KeyValue> <DSAKeyValue> <P> </P><Q> </Q><G> </G><Y> </Y> </DSAKeyValue> </KeyValue> </KeyInfo> </Signature> Listing 7. An example of XML signature (Source: W3C) 2128 Web Services Security in E-Business attackers generally manipulate SOAP messages for attacking Web services, it is inadequate for WUDGLWLRQDOQHWZRUN¿UHZDOOVWRSURWHFWWKHH[LVW- ing Web service architecture. Web service-based intrusion detection and prevention systems may address this issue. 7KH\FDQPRQLWRU62$3WUDI¿FDQGLQVSHFWWKH SOAP contents for anomaly behaviors or intru- VLRQSDWWHUQV 0DOLFLRXV 62$3 WUDI¿F VXFK DV parameter tampering and SQL injection, should be denied before they travel to a critical system. ,QDGGLWLRQWKH\VKRXOGYDOLGDWHV\QWD[RI62$3 PHVVDJHVDQG¿OWHUWKRVHZLWKLPSURSHUV\QWD[ such as oversized payloads. The systems may also provide access control based on different roles, groups, and responsibilities for preventing XQDXWKRUL]HGXVHRI:HEVHUYLFHV)RUH[DPSOH only authenticated business partners are allowed to view some of the restricted WSDL documents for critical Web services. FUTURE TRENDS ,WLVH[SHFWHGWKDWQHZVSHFL¿FDWLRQVDQGSURWRFROV ZLOOEHGH¿QHGDV:HEVHUYLFHVWHFKQRORJ\HYROYH Also, new applications related to Web services will be developed gradually. All these new technolo- gies may introduce new vulnerabilities to the Web VHUYLFHVDUFKLWHFWXUH,WLVUHTXLUHGWRH[DPLQH every security aspect of the new Web services technologies. The study and analysis of potential attacks and their countermeasures is important in this issue. Automated testing or benchmarking tools may be developed for evaluating the security of the Web services. Malicious codes such as viruses and worms VSUHDGDFURVVWKHH[LVWLQJQHWZRUNLQIUDVWUXFWXUH and result in a great deal of business loss. It may foresee that the Web services architecture will be another new avenue for the propagation of the malicious codes. Antivirus scanners should ensure that they have the ability to recognize ma- OLFLRXVFRGHVWKDWHPEHGGHGLQ;0/GRFXPHQWV as well as to control the propagation of malicious software within the Web services architecture (Negm, 2005). *XWLpUUH]HWDOVWDWHGWKDWDQ;0/YR- F D E X O D U \IR U H [ S U HV V L QJ D X G LW G DW D D QG S U RW R F R O IR U  GLVWULEXWHGDXGLWSURFHVVHVPD\EHGH¿QHGDVDQ H[WHQVLRQWRVRPHH[LVWLQJVHFXULW\VSHFL¿FDWLRQV They also proposed that contingency protocols, security alerts management, and countermeasures need to be developed in the future. All these UHVHDUFKHVZLOOEHHVVHQWLDOIRUEXLOGLQJHI¿FLHQW intrusion detection and prevention systems in the Web services architecture. CONCLUSION Web services provide a framework for inter- V\VWHP FRPPXQLFDWLRQ WKDW HQDEOHV ÀH[LEOH implementation and integration of e-business systems. However, there are risks for adopting Web services by enterprises if they do not address security challenges in the Web services architec- ture. Therefore, it is crucial for the developers and users to understand the security issues in Web services. This chapter is meant to provide a state-of-the-art view of security attacks and preventive countermeasures in Web services. We presented core components of Web services such as SOAP, WSDL, and UDDI. In addition, we EULHÀ\GLVFXVVHGWKHLUUROHVDQGRSHUDWLRQV7KH inherently insecure nature of the Web services architecture is susceptible to numerous attacks. :HDOVRGLVFXVVHGWKHVHDWWDFNVDQGH[DPLQHG KRZDWWDFNHUVH[SORLWYXOQHUDELOLWLHVLQWKH:HE services architecture. Proper security schemes should be applied to counter these attacks. We presented these security countermeasures and VSHFL¿FDWLRQV WR SURWHFW :HE VHUYLFHV GHSOR\- ments in e-business. 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Retrieved August 4, 2005, from http:// GRFVRDVLVRSHQRUJ[DFPODFFHVVBFRQWURO [DFPOFRUHVSHFRVSGI Nadalin, A., Kaler, C., Hallam-Baker, P., & Monzillo, R. (Eds.). (2004). Web services security: SOAP message security 1.0 (WS-Security 2004) (OASIS Standard). Retrieved August 4, 2005, from http://docs.oasis-open.org/wss/2004/01/oa- sis-200401-wss-soap-message-security-1.0.pdf 1DHGHOH06WDQGDUGVIRU;0/DQG:HE services security. IEEE Computer, 36(4), 96-98. Negm, W. (2004). Anatomy of a Web services attack. Retrieved April 26, 2005, from http:// forumsystems.com/papers/Anatomy_of_At- tack_wp.pdf Negm, W. (2005). XML malware: Controlling the propagation of malicious software within service oriented architectures. Retrieved July 15, 2005, from http://forumsystems.com/papers/Fo- UXPB;0/B0DOZDUHBZSBVXPPHUBSGI Thompson, H., Beech, D., Maloney, M., & Men- delsohn, N. (Eds.). (2004). XML schema part 1: Structures (W3C Recommendation). Retrieved April 18, 2005, from http://www.w3.org/TR/2004/ 5(&[POVFKHPD Wilson, P. (2003). Web services security. Network Security, 2003(5), 14-16. This work was previously published in Web Services Security and E-Business, edited by G. Radhamani and G. Rao, pp. 165- 183, copyright 2007 by IGI Publishing (an imprint of IGI Global). 2131 Copyright © 2009, IGI Global, distributing in print or electronic forms without written permission of IGI Global is prohibited. Chapter 7.11 A Security Blueprint for E-Business Applications Jun Du Tianjin University, China Yuan-Yuan Jiao Nankai University, China Jianxin (Roger) Jiao Nanyang Technological University, Singapore ABSTRACT This chapter develops a security blueprint for an e-business environment taking advantage of the three-tiered e-business architecture. This security blueprint suggests best practices in general. It involves (1) security control by layers — from physical access, to network communica- tion, to operating systems, to applications, and (2) different stages of the management process, including planning, deployment, administration, and auditing. Also reported is a case study of the implementation of the proposed security blueprint in a Singapore multinational corporation. Such issues as security control analysis, management SURFHVVDQDO\VLVDQGFRVWEHQH¿WVDQDO\VLVDUH discussed in detail. INTRODUCTION The Internet has created huge opportunities for new companies and new business for those established organizations formerly bound by a saturated market. (EXVLQHVV LV GH¿QHG DV WKH c o nd u ct i o n of b u si n e s s w i t h t he a s si s t a n c e of t el e - communications and telecommunication-based tools, mainly over the Internet (Clarke 1999), including business-to-business (B2B), business- to-customer (B2C), and intra-organizational com- merce (Siau & Davis, 2000). Security is essential and very critical to e-business applications. The importance of information privacy to e-business has been recognized for some time (Agre & Ro- tenberg, 1997; Bingi, Mir, & Khamalah, 2000; Lichtenstein & Swatman, 2001), with the Gartner 2132 A Security Blueprint for E-Business Applications Group (2002) nominating information privacy as the greatest impediment to consumer-based e-business through 2006. However, when building up a secure environ- ment for e-business applications, there are no industry standards for people to follow on their design or implementation jobs. All that can be referred is from the security product manufac- turers and system integrators. The truth is that security systems can only provide a certain level of protection to an e-business environment. Therefore, security protection must be in place at different layers, and the management process must be carried out at different stages. From the authors’ viewpoint, security is not a by-product; it is a combination of managing technologies and VHFXULW\SURFHVVHVUDWKHUWKDQ³SXWWKH¿UHZDOO here, put the intrusion detection system there.” This chapter develops a security blueprint for a typical e-business environment based on the discussion of the major components in three-tiered e-business architecture. This security blueprint includes general security control layered from physical access, network communication, operat- ing system, to application; and security manage- ment processes staged from planning, deployment, administration, to auditing. TYPICAL E-BUSINESS ENVIRONMENT Originally, business computing was carried out as a point task, without any real concept of a net- worked operation. All the business processes are run on a single platform or single tier. Later, many systems evolved to a two-tiered approach, also known as client/server architecture, where most of the business process runs on the server and the client is mainly concerned with presentation and RQ O\KROGVDOL PLWHGDPRX QWRIXVHUVSHFL¿FGDWD Today, more and more e-business applications are deployed as a three-tiered architecture owing to LWVLQFUHDVHGSHUIRUPDQFHÀH[LELOLW\PDLQWDLQ- ability, reusability, and scalability, while hiding the complexity of distributed processing from the user. After this, things get more complicated, with additional applications running in different tiers, which is so-called multi-tiered architecture. However, multi-tiered architectures have arisen not necessarily because great thought was given to this choice of architecture; in truth, they are more the result of trying to make the best of what was there. This section will describe a typical three-tier e-business environment and identify the major components from system architecture perspec- tives. Three-Tier E-Business Architecture When it comes to an e-business environment, usually, these three tiers (layers) can be described as the presentation layer, business logic layer, and data layer. These tiers are logical, not physical. One machine can run several business tiers and tiers can be distributed across several machines. A typical three-tiered e-business architecture is shown in Figure. 1. Major Components in an E-Business Environment In the three-tiered e-business architecture, the PDMRU FRPSRQHQWV FDQ EH LGHQWL¿HG DV D :HE browser, a Web server, an application server, a database server, an AAA/directory service, a corporate network, and the Internet, as illustrated in Figure 2. A SECURITY BLUEPRINT A secure e-business environment must prevent most attacks from successfully affecting valuable e-business resources. While being secure, the e- business environment must continue to provide critical services that users expect. Proper security 2133 A Security Blueprint for E-Business Applications Figure 1. A typical e-business environment Figure 2. Major components in an e-business environment . et al. (Eds.), Computational science and its applications — ICCSA 2004, Proceedings of the International Conference on Computational Science and Its Applications — ICCSA 2004, Assisi, Italy. process runs on the server and the client is mainly concerned with presentation and RQ OKROGVDOL PLWHGDPRX QWRIXVHUVSHFL¿FGDWD Today, more and more e-business applications are deployed. Security and E-Business, edited by G. Radhamani and G. Rao, pp. 165- 183, copyright 2007 by IGI Publishing (an imprint of IGI Global). 2131 Copyright © 2009, IGI Global, distributing in print or electronic