Multi-core Computing Security: Lecture 43 - Multiprocessor Techniques, Slides of Computer Science

Download Multi-core Computing Security: Lecture 43 - Multiprocessor Techniques and more Slides Computer Science in PDF only on Docsity! Objectives_template file:///D|/...ary,%20Dr.%20Sanjeev%20K%20Aggrwal%20&%20Dr.%20Rajat%20Moona/Multi-core_Architecture/lecture%2043/43_1.htm[6/14/2012 12:18:10 PM] Module 22: Multi-core Computing Security Lecture 43: Multiprocessor Techniques The Lecture Contains: Producer and Consumer Code Message Passing Synchronization With Messages Buffering Model Multiprocessor Techniques First Job Decipher Security Infrastructure Goals: Confidentiality Goals: Integrity Goals: Availability Policies Mechanisms Enforcement Media Threat and Attack Information Security Threat Perception and Cost of Security Cryptography: кρυptο γρafη(hidden writing) Cryptography Objectives_template file:///D|/...ary,%20Dr.%20Sanjeev%20K%20Aggrwal%20&%20Dr.%20Rajat%20Moona/Multi-core_Architecture/lecture%2043/43_2.htm[6/14/2012 12:18:10 PM] Module 22: Multi-core Computing Security Lecture 43: Multiprocessor Techniques Producer and Consumer Code BUF_Data consume(void) { while (buffer.outptr == buffer.inptr) ; buffer.items[buffer.outptr]; buffer.outptr = (buffer.outptr +1)%BUF_SZ; return (buffer.items[buffer.outptr-1]%BUF_SZ;); } What is wrong with this code? Message Passing Communication channel How to name the channel between two processes? Direct Communication The sender process (P) must know the receiver process (Q) and vice versa P: send(Q, msg) ♦ Q: receive(P, msg); Some versions may have receive(ANY, msg); Indirect Communication Mailboxes must be named rather than the processes. Sender: Create_mailbox(Name, Properties); Sender: Send(Name, msg); Sender: Distroy_mailbox(Name); Receiver: Open_mailbox(Name); Receiver: Receive(mailbox, msg); Objectives_template file:///D|/...ary,%20Dr.%20Sanjeev%20K%20Aggrwal%20&%20Dr.%20Rajat%20Moona/Multi-core_Architecture/lecture%2043/43_5.htm[6/14/2012 12:18:11 PM] Module 22: Multi-core Computing Security Lecture 43: Multiprocessor Techniques Decipher Si spy net work, big fedjaw iog link kyxogy Replace S by T Ti tpy net work, big fedjaw iog link kyxogy Replace i by o To tpy net work,bog fedjaw oog lonk kyxogy Replace p by h To thy net work,bog fedjaw oog lonk kyxogy Replace y by e To the net work,bog fedjaw oog lonk kyxoge Replace n by b To the bet work, bog fedjaw oog lobk kyxoge Replace e by a To the bat work,bog fadjaw oog lobk kyxoge Replace t by d To the bad work,bog fadjaw oog lobk kyxoge Replace k by s To the bad wors, bog fadjaw oog lobs syxoge Replace w by g To the bad gors, bog fadjag oog lobs syxoge Replace o by u To the bad gurs, bog fadjag oug lobs syxuge Replace g by r To the bad gurs, bor fadjag our lobs syxure r byy,bbyf, … To the bad guys, for making our jobs secure Security Infrastructure Objectives_template file:///D|/...ary,%20Dr.%20Sanjeev%20K%20Aggrwal%20&%20Dr.%20Rajat%20Moona/Multi-core_Architecture/lecture%2043/43_6.htm[6/14/2012 12:18:11 PM] Module 22: Multi-core Computing Security Lecture 43: Multiprocessor Techniques Goals: Confidentiality Access to information or resources only to authorized users/entities/persons. Mechanism: Access Control List (ACL) or Access control specifications Data encryption Must have a mechanism to authenticate Password, Cryptographic techniques Some time necessary to even conceal the fact that the information exist. Access control on directories, Steganography Goals: Integrity “Can I trust the information?” Data integrity to ensure that the data is genuine and is not modified Some time need to ensure that data originated from the right place Origin integrity Mechanism Cryptographic techniques Hashing techniques Checksums and use of alternate channels to send them. Objectives_template file:///D|/...ary,%20Dr.%20Sanjeev%20K%20Aggrwal%20&%20Dr.%20Rajat%20Moona/Multi-core_Architecture/lecture%2043/43_7.htm[6/14/2012 12:18:11 PM] Module 22: Multi-core Computing Security Lecture 43: Multiprocessor Techniques Goals: Availability A most common attack is “denial of service” attack. Attacker does not get the access but can prevent other authorized users getting access as well. Policies “What is permitted” For example “only course students can have read access to the these lecture notes” Policies are usually defined by the administrator or owner of the resource. Mechanisms Mechanisms are techniques/methods to enforce a policy For example a “attributes” associated with a file can be changed by the owners Mechanism need not even be technical A lost ID card application must be approved by the Dean’s office before a new one is issued. In computer related security, typically procedural mechanisms are used.