CRYPTOGRAPHIC CONTROL FOR RISK ASSESSMENT ON UNIX OPERATING SYSTEM-I

International Journal in Foundations of Computer Science & Technology (IJFCST), Vol. 3, No.1, January 2013 DOI:10.5121/ijfcst.2013.3104 37 CRYPTOGRAPHIC CONTROL FOR RISK ASSESSMENT ONUNIX OPERATING SYSTEM-I 1Dr. Prashant Kumar Patra & 2Padma Lochan Pradhan 1.Dept. of CSE, College of Engineering & Technology, BPUT, Bhubaneswar-751003 2.Dept. of CSE, Sikha ‘O’ Anusandhan University (SOA). Bhubaneswar, Orissa, India ABSTRACT The increased of the use of computer & communications system by IT industries has increased the risk of theft of proprietary information. Cryptographic control (Encryption) is a primary method of protecting system resources. Control is inversely proportional to the Risk ( C=K/R) & mean while control is directly proportional to the quality of standard( S ). Control will be optimize the risk as well as improve the IS standard. Control is directly proportional to mitigation & mitigation is directly proportional to standard. Encryption Key length (E) is inversely proportional to the Risk. This paper contributes to the development of an optimization model that aims to determine the optimal cost to be invested into security model & mechanisms deciding on the measure component of operating system resources (i.e. Processor, Memory and Encryption). Furthermore, the model & mechanism optimize the cost, time & resources is supposed to reduce the system risks. KEYWORD PC-Preventive Control, DC-Corrective Control, CC-Corrective Control, CKM-Cryptographic Key Management. AES: Advanced Encryption Standard. CPU: Central Processing Unit. ROI-Return on Investment, SSH –Secure Shell, TCO-Total Cost Ownership, RM-Risk Mitigation. 1. INTRODUCTION The machine is consists of millions of chips, each capable of testing a million keys per second, such machine could be test 2^56 key in 20 hours. It is easy to design a machine with a million parallel processors, each working independent of the others. The encryption key length size is depends Memory, Control, Arithmetic unit, Processor etc. to perform the functionality of the operating system. The operating system control is the process to address security weaknesses in operation systems by implementing the latest OS patches, hot fixes and updates and the procedures and policies to reduce attacks and system down time mean while increase the throughput of the system. Preventive control of the operating systems is the first step towards safeguarding systems from intrusion, workstations, applications, network and servers typically arrive from the vendor, installed with a multitude of development tools and utilities, which although beneficial to the user, also provide potential back-door access to the systems. Control of an operating system involves the removal of all non essential tools, utilities and other systems programmer options, any of which could be used to ease a hacker's path to our systems. International Journal in Foundations of Computer Science & Technology (IJFCST), Vol. 3, No.1, January 2013 38 Security is a process, not a result. It is a process which is difficult to adopt under normal conditions; the problem is compounded when it spans several job and application running simultaneously under complex based web infrastructure which using million of user accessing the same piece of devices and information or data on the around the clock ( 24 x 7 x 52 ). All the system level security in the world is rendered useless by insecure web-applications. The converse is also true, programming best practices, such as always verifying user inputs are useless when the code is running on a server which hasn’t been properly system programmed. Control is directly proportional to hardening or vice versa. Securing forward facing free BSD, GNU, SystemV based unix and Linux web servers can seem like a counting task, but it can be made much easier by breaking the process into manageable portions. Literature Survey: [4], [5], [16] & [17] The technical literature survey in IS Security area is very critical & tedious task to collect the actual data and evidence in the real life. It is one of the ongoing process in a continuous manner. It is a very time consuming to investigate & judge the information. There are many text book & reference books help to us to find out the real issue. The reference books like: Applied Cryptography by Bruce Schneier and Cryptography & Network Security by William Stalling is very much help full to expand our idea. The object oriented java programming is very help to make programming for cryptographic key management issue. The Sun Micro-system UNIX sun solaris system administration guide: Vol 1 & Vole 2. & O’ Reilly, Essential of System Administration is helpful to collect the basic data in real life environment. Nowhere of the above documents reflected the issue of the System Characterization, Risk Identification, Risk Analysis, Vulnerability, Risk Mitigation Method & Model, Control Analysis, Impact Analysis and Benefits .This issue is highlighted in our action plan and proposed method. We have to find out some method, to make the more efficient secure, high available & robust high end operating system with encryption key. No, where develop the following method in Graphically as well as Mathematically. We have to develop the following issue for betterment of the IS organization. There are many things not develop till now like : system Characterization, Risk Identification, Risk Analysis, Vulnerability Identification, Risk Mitigation Model & method, Control Analysis, Impact Analysis, Risk Determination, Control Recommendations & Results. We have to develop Risk Identification, Risk Analysis, Vulnerability Identification, Risk Mitigation in both analytical & graphical way. There many documents are available in general sense of risk identifications, risk analysis, risk mitigation, but operating system level, system software, application software, database, network and middleware level, the classification & categorization of risk is not available on today itself. Existing Encryption Control: System Programmed (Automated control)[7],[8] We have to develop this method based on our past experience of the hardening as well as controlling of operating system and network issue. Part of our assessment of the controls will necessitate an evaluation of the use of automated or programmed controls to mitigate risk as opposed to manual controls that also may be implemented to perform similar functions. The International Journal in Foundations of Computer Science & Technology (IJFCST), Vol. 3, No.1, January 2013 39 common wisdom is that programmatic controls will work without fail because the machinedriven control does not have an opportunity to ignore its programming as human process might. However automated controls come at price. They must be tested, coded, monitored and maintained to be effective. When circumstances or risks changes, these controls must be reconfigured and go through another rigorous development and testing cycle. They will not work just as automatically when systems are not set up correctly as they would work effectively when the implementation of the control is done correctly. Automated systems do not think or recognize bad instructions in most cases. However, they are much more reliable than manual controls and can be assumed to be working in an unattended fashion, with only minor monitoring to ensure continued effectiveness once way are up & running. When drawing conclusions on the overall effectiveness and cost of automated controls, the building, maintaining, and monitoring costs must be offset by the potential losses to best understand the cost effectiveness of the controls. Additionally, the reliability or net effectiveness of the controls, which are assumed higher in automated and programmatic implementation, also must be factored in. Where loss due to risk cannot be left to change, automated controls should be recommended. Because we will, no doubt, be focusing on the high risk situations as we triage our work and provide risk-based solutions to our clients these will be our recommendations more often than not. Proper research, investigation, survey, implementation and routine monitoring are a prerequisite. Encryption control is a major action plan for control system which prevent the major components of IT infrastructure. We have to followup the following file system to develop the CKM issue. Table:1 1 . etc/ssh/sshd_config Cryptiographic Control based on AES Cryptography enable through ssh implementation AES: 256 bits chipper. chipper blowfish-CBC,aes256-CBC, aes256-chr.ssh-key gen -b 1024 -f /etc/ssh_host_key -n '' chmod - - - /etc/ssh/ssh_config Preventative control n=1024, 2048, 4096 chimed r w x (i. e. 4 2 1 ) –blank is nothing [ H, M, L ] DATA COLLECTION BASED ON EXISTING CONTROL: (BASIC DATA) There are number of hardening and control methods developed as per requirement of the secure computing to achieve the highest level of business objective. There is a few method developed based on unix server and operating system programming. Unix file system have to be develop as per business requirement: ( BASIC DATA )[13],[18],[19] International Journal in Foundations of Computer Science & Technology (IJFCST), Vol. 3, No.1, January 2013 40 Table: 2 S N SYSTEM FILES ACTION PLAN REMARKS 1 /etc/system Can be update the kernel & n-bit processor Can be improve the system performance 2 /etc/hosts Develop the scripts: allow/disallow as per policy, chimed 000= /etc/mark disallow Preventative control [ H, M, L ] 3 /etc/services Disable the third parties services. Remove the ftp, http, telnet, port no, printer, IP services. Those services are not required. Preventative control [ H, M, L ] 4 /use/bin/rash, etc/pam.conf Disable all remote services: chmod 000 /usr/bin/rsh, rksh,rcp, ruser,rlogin, uptime. Preventative control 5 /vary/dam/message Date & time stamp ( DC) Internal audit purpose [ H, M, L ] 6 /etc/rc.conf script Run level script Run level script have to develop as per requirement. /etc/init.conf,rc2.d example:httpd_flags="NO" Preventative control [ H, M, L ] 7 /etc/init.conf OS services, run level Preventative control Problem in existing Control: [7],[8] •The IS security is a process which is difficult to adopt under normal conditions; the problem is compounded when it spans several jobs and applications running simultaneously under complex based web infrastructure which using million of user accessing the same piece of devices and information or data on the around the clock ( 24 x 7 x 52 ). The ssh key 1024 & AES key 256 is limited shorter key size. OS Hungering & control as well as high utilized of CPU Times: system throughput became slow down. Slow down the network resources, loss of communication system. There is no balance ratio among the Processor, Memory & Time slot of the high end OS. •When too many packets are present in the subnet, performance degrades and in this situation data/packet congestion is happening. In this way transmission error is happening. At the high end traffic, performance collapses completely and almost no packet is delivered. If there is insufficient memory to hold all of them, packet will be lost. If slow the processor can also cause the congestion. Similarly, the low bandwidth can also cause congestion. Therefore, the OS became hungering & highly utilizing of CPU Times, system throughput became slow down, also slow down the network resources & loss of communication system. There is no protection, detection & automatic correction on the Shell, File & Kernel. There is no balance ratio among the Kernel, Processor, Memory, File System [Encryption Key] & Time slot of the high end OS. The high level decision process is required to implement resources like kernel, processor and instruction level parallelism (SISD, SIMD, MISD, MIMD ) & high memory & encryption key sizes for high end business. The high end technology would be match with high volume business. International Journal in Foundations of Computer Science & Technology (IJFCST), Vol. 3, No.1, January 2013 41 Why we use stronger (larger ) key sizes? Problem in existing control: due to shorter keys size That’s why we are using stronger key: AES 512, 1024, 2048 & so on. Increasing the business ( large volume of data, Information, data warehousing & data mining. •Increasing the million of users. •Increasing the hackers as well as experiences hackers. •Increasing the hardware & software capabilities ( n-th bits processor & no of CPU, Memory). Our proposed cryptographic key management ( encryption) control will be help to : •Business continuity planning & disaster planning (BCP/DRP) •Internal & external system audit. •Keep the system balance among devices, sub-systems, resources & users need. •Improve the throughput, interoperability, CPU utilization, total cost ownership (TCO) & Return on Investment ( ROI, ROA) •The least cost & best fit approach. PROPOSED CONTROL: CRYPTOGRAPHIC ENCRYPTION CONTROL: ( ANALYTICAL & GRAPHICAL METHOD ) The Cryptographic Key Management (CKM) keys must be securely managed when cryptographic functions are implemented in various other controls. Cryptographic key management includes key generation, distribution, storage and maintenance purpose. This is a measure preventive control in security world around the globe. As a brief, in the operational security domain, preventive controls are designed to achieve two things: to lower the amount and impact of unintentional errors their are entering the system and to prevent unauthorized intruders from internally or externally accessing the system. An example of these controls might be renumbered forms or a data validation and review procedure to prevent duplications. How the operating system maintaining ratio & proportion among various sub systems like server key, encryption key, processor & memory capability, availability and efficienciency. This issue is high lighted in our action plan. We have to find out some method, to make the more efficient, secure, high available & reliable the robust high end operating system. The SSH key in the existing Unix based operating system support only up to 1024 etc/ssh/sshd_config ( Cryptography enable through ssh implementation AES: 256, bits chipper, chipper blowfishCBC,aes256-CBC, aes256-chr.). The existing system supporting only 1024 in SSH key & 256 key size in AES Level. These AES-256 and SSH-1024 is not sufficient for high end processor, CPU, Memory, instruction pipe lines ( SIMD, MISD, MIMD) . But, the propose control will be facilitate and resolve the various problems when it spans several jobs and applications are running simultaneously under heterogeneous complex infrastructure & mobile computing environment, which using million of user accessing the same piece of data around the clock( 24 x 7 x 52 ). [Internet & Intranet ]. International Journal in Foundations of Computer Science & Technology (IJFCST), Vol. 3, No.1, January 2013 42 Flow diagram of detail work: system program (proposed method ) PREVENTIVE CONTROL TOOLS & TECHNIQUE: Technical security controls for risk mitigation can be configured to protect against given types of threats. These controls may range from simple to complex measures and usually involve system architectures; engineering disciplines; and security packages with a mix of hardware, software, and firmware. All of these measures should work together to secure critical and sensitive data, information, and IT system functions. Technical controls can be grouped into the following: critical, major, minor ( H, M, L) categories, according to primary purpose: Supporting controls are generic and underline most IT security capabilities. These controls must be in place in order to implement other controls which are deals with the system & sub system, devices dependencies. Preventive controls focus on preventing security breaches from occurring in the first place. Preventive control is the cryptographic control. These controls focus on detecting (DC)and recovering (CC) from a security breach. We can define Mathematically and Graphically as follows: C=K= (PC+DC+CC), Cα1/R, C α S. International Journal in Foundations of Computer Science & Technology (IJFCST), Vol. 3, No.1, January 2013 43 Control flow chart: Proposed Control (Cryptography based system control ): Our Action Plan Aim and Objective of the Thesis: a).To investigate the preventive control and technique to safe guard our operating system that should be free from risk. Our objective is that, to find out the maximum policy, procedure, tools (CKM), commands & technique how to safe guard our assets from internal and external hacker as well as misuse of the critical infrastructure components like ( N-tire architecture) network components, operating system , server, data and file, database, middleware, application, scanner, printer and storage devices. Therefore, the following sub systems have to protect as per business requirement. Prevention is the first step of the risk assessment of the critical IT infrastructure. We are going to develop many more hard core prevention methods to protect the multi-tire architecture for web based application, which is facilitating million of customers . To maintain the integrity & privacy of the sub system for multi-core operating system as well as current virtualization technology. There are four level of prevention control methods are require to minimize the risk of any web based multi-tire infrastructure. •Operating system control ( Sun Solaris, AIX, LINUX, HPUX, NT, Microsoft OS) •Network control ( Load balancing, Clustering, DNS, Firewall, Proxy, Squid, SSH, SSL, FTP, LDAP) •Database control •Application Control (cryptography, mod-ssl, mod-security, mod_autho & vintila ) b). Minimize the Risk: ( PC=K/R) International Journal in Foundations of Computer Science & Technology (IJFCST), Vol. 3, No.1, January 2013 44 Meanwhile we have to investigate and audit the system security for detection, prevention & corrective action for minimize the various level of risk : like : High, Medium & Low. Risk is never eliminated, only we can able to minimize into lowest level. We can minimize the risk on IT infrastructure in the three ways of doing continues ways process of protection, detection and risk assessment method. But, risk never be eliminated. Risk can be transferable and minimize. We should always optimize the risk at the minimum level to protect our critical IT infrastructure and assets as well as sub systems ( OS : processor, multi-plexier, memory, cpu and other related components). In this paper, we are focusing only operating system level : (Advanced Cryptography Encryption control) Control is directly proportional to AES-M. (PC=keys-M) [Where M=512, 1024, …….. ] & AES & CKM key size inversely proportional to the risk. PC=K/R. where k is the constant factor, then automatically reduced the risk. But, there is some limitation of architecture of processor & memory ( instruction pipe lines: SIMD, MIMD, MISD ) capability of the operating system for large based key generation of AES & CKM. PROPOSED ALGORITHM: Advanced key expansion algorithm: The advanced key expansion algorithm scheme takes as input a 4-word (N), ( 16-byte ) key and produces a linear array of 44 words ( 176 bytes). This is insufficient to provide a 4-word round key for the initial add round key stage and each f 10 rounds of the chipper. The following pseudo code describes the expansion. Let us consider N = 4, 8, 16, 32…… Advanced key expansion ( byte key {16 }, word w [44] ) {word temp for ( i = 0; i < N; i++ ) w[i] = ( key [ N*i ], key [N*i+1] ) , key [N*i+ 2] , key [N*i+ 3] ); for ( i = N; I < 44; i++ ) {Temp = w [ i - 1 ]; if ( i mod N = 0 ) temp = SubWord ( RotWord (temp ) ) Rcon [ i/N ]; w[ i ] = w [ i - N ] = temp } }The key is copied into the first four words of the expanded key. The reminder of the expanded key is filled in four words at a time. Each added word w{i} depends on the immediately preceding word, w[i –1], and the word four positions back, w[i –N ]. In three out of four cases, a simple XOR is used. For a word whose position in the w array is a multiple of 4 (i.e N), a more complex function is used. International Journal in Foundations of Computer Science & Technology (IJFCST), Vol. 3, No.1, January 2013 45 CRYPTIOGRAPHIC CONTROL RESULT & DISCUSSION: Based on the above algorithm, we can decide the programme ( JAVA/C++) , then we can find out the /var/adm/message ( action & reaction ) of the JVM issue as well as space utilization like RAM & Cache etc ( space & time complexity). Mean while we can use the various system commands and scripts for further review and analysis of the unix based server. How is behaving the server and its sub components, when we are running on the different processor & CPU of the same cryptographic algorithm program AES512, AES1024)? How far is system (hardware, software, application, network bandwidth & related devices) maintaining risk level, we can only review practically based on theoretical idea. We can review the system behavior with space & time complexity. How is system is behaving when million of users accessing the same piece of devices? HOW TO INVESTIGATE CRYPTOGRAPHIC CONTROL RESULT ON UNIX OS: •A. RISK IDENTIFICATION ( Detective Control): Intrusion Detection System : In unix operating system, the risk can be identified by the following dynamic OS logs. (date and time stamp ) •/var/adm/syslog : syslog system logs /var/adm/sulog : super user log /var/adm/loginlog : user login log /var/adm/message >> Temp # using last| head or tail -f /var/adm/syslog, tail –f /var/adm/message . These logs are very helpful to the internal as well as external audit purpose. The incident management department analysis these logs to mitigate the risk factor. •B. RISK ANALYSIS: (above system logs: DC) Meanwhile we have to investigate and audit the system security for detection, prevention & corrective action for minimize the various level of risk : like : High, Medium & Low. Risk is never eliminated, only we can able to minimize into lowest level. High level preventive control will be take care of minimize the lowest level of risk. (Prevention is inversely proportional to Risk) PC=k/R and PC=k.S ( k is the proportionality constant ) or CKM =kS REVIEW THE INTERNAL OS by applying the following commands and scripts in key boards in super user mode. International Journal in Foundations of Computer Science & Technology (IJFCST), Vol. 3, No.1, January 2013 52 OPTIMIZED LEVEL(P-P-P=>P-P-P) Digonal view (Processor:PC) We can conclude that from the Model 3, 4 & 5 the memory, encryption & processor have to take highest priorities of the preventive (PC) control plan, which is shown in the table 7, 8 & 9 respectively. In this way, we can improve the high end processor, CPU, Memory, instruction pipe lines like :SIMD, MISD, MISD. MIMD . But, the encryption controll will be facilitate and resolve the various issue when it spans several jobs and applications are running simultaneously under heterogeneous complex based web infrastructure around the globe. These above optimization model will be very helpful for Instruction level parallelism for high end computing. We hope this theoritical and experimental idea will be very much help to the parallel computing environament to optimize the hardware & software risk. The clear cut picture already mentioned in the Table:4. We can assume the the encryption control matrix will be help to the following points. FUTURE ADVANCEMENT OF THIS WORK: •We have to develop space & time complexity based on our requirement ( Ref to Table: 4) •Top Mgmt have to decide the encryption standard ( AES, SSH & CKM ) key sizes as per business requirement & availability of resources. ( Ref. Table: 4) •Based on above two points, we can improve the operating system performance. BENEFITS: DECISION MAKIND DATA FOR RISK MGMT a. The top management have to decide the optimal cost of HW/SW.( Processor, Memory, CPU, IO Units & Multiplexers ). b. Capacity planning of operating system c. Business continuity planning & Disaster recovering planning ( BCP/DRP) d. Risk Assessments & Mitigation e. Internal & External audit. f. The top management have to decide the encryptions standard (AES, SSH, CKM) key sizes as per business requirement. Risks –Results: •There are three categories of results developed on the basis of CKM control on the Unix operating systems. •Monetary –Financial Loss relating to under performing and unsecured resources being used within the organization. •Productivity –Cost of fixing the machines affected in terms of end-user and system programmer, lost productively due to a loss of functionality (server crash or compromise) and performance & Security issue. •Trust –Loss of good faith of customers, vendors, client and users. It is impossible to regain in e-Commerce, B2B, B2C & mobile computing environment. International Journal in Foundations of Computer Science & Technology (IJFCST), Vol. 3, No.1, January 2013 53 Summary: •The cryptographic control provides accountability for individuals who are accessing sensitive information on application, system software, server and network. This accountability is accomplished through access encryption control mechanisms that require identification, authentication, authorization, accountability, non-repudiation, availability, reliability & integrity through the audit function (/var/adm/message). By the help of these model we can keep the balance ratio among the Processor, Memory, Encryption key & Time slot of the high end OS as per business requirement and availability of the resources around the globe in basis of 24 x7 x 52 pattern . •The encryption control is a one of the efficient & best control for risk management. Alternatively we can say preventive & automated control which is help to reduce the risk of the IT infrastructure. This control is mostly acceptable on heterogeneous hardware like: INTEL, MAC & MOROLA. •Risk can be mitigate by ongoing process of various action plan of control of OS, Network, Database, Application and devices as well as relevant resources of the IT infrastructure. •To minimize the risk, operating system hardening, preventive, detective and corrective action is the most well advanced action plan for the long term business activities of the every organization. Therefore, contingency plan is the most effective & efficient plan for safe guard of the organizational assets. Therefore operating system control, anti-virus solution, periodically security system programming (SSH,AES) & patches updation are the most preventive, detective and corrective action plan of the any organization to survive. In summary, the risk assessment process is about making decisions to minimize the risk. The impact of a successful attack and the level of acceptable risk for any given situation is a fundamental policy decision. Likewise, vulnerabilities are design issues and must be addressed during the design, development & implementation of information resources. •A sound information security policy identifies prevention, detection, and response measures. The appendix provides more details on risk assessment tools and practices that may be used to improve information security programs. Preventive measures may include regularly using vulnerability assessment tools and conducting periodic penetration analyses. Intrusion detection tools can be effective in detecting potential intrusions or system misuse. Institutions should also develop a response. •By reading through this paper and utilizing the checklist for preventive, detective and corrective action plan of that organization, an OS and Security programmer & administrator now has a base knowledge of security, server hardening, intrusion detection, auditing, and security tools. This knowledge can be directly applied to their servers and many vulnerable holes will now be filled. Bear in mind that many holes that exist have yet to be discovered. Therefore, it is critical that every Unix security-minded programmer maintains their knowledge of security by researching and referring to the Internet resources that have been mentioned. If there is ever a question about updation & implementation of any of the suggested features, refer to the OS server Security manuals that were designated with the specified feature (all features have been research, design, developed & documented). 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