Toshihiro Tabata

Program obfuscation scheme using random numbers to complicate control flow

For the security technology that has been achieved with software in the computer system and the protection of the intellectual property right of software, software protection technology is necessary. One of those techniques is called obfuscation, which converts program to make analysis difficult while preserving its function. In this paper, we examine the applicability of our program obfuscation scheme to complicate control flow and study the tolerance against program analysis.

A Recyclable Resource Management Method for Fast Process Creation and Reduced Memory Consumption

Findings by duration dependence test indicate that there are significant bubbles in market response to merger & acquisition. This paper compares the different responses caused by the same event between Shenzhen security market and Shanghai security market.The costs involved in process creation and termination make this procedure expensive. This procedure expensive, thus degrading the performance of program execution. To solve this problem, a fast process creation and termination mechanism is proposed. This mechanism is implemented by recycling process resources. In order to improve the efficiency of recycling, the management of preserved process resources for recycling is an important factor. In this paper, we propose an improved resource management method for recycling process resources and an adaptive control mechanism. In the method, only one process resource with a program image is preserved for each program that occurs with high frequency of program execution. The proposed method can reduce the amount of memory consumption for preserved process resources in a concurrent execution environment. We also describe the implementation of the proposed method on the tender operating system and report the results of our experiments.

Controlling CPU Usage for Processes with Execution Resource for Mitigating CPU DoS Attack

In a ubiquitous environment, the hardware resources are limited; thus, an appropriate resource management mechanism is required for guaranteeing its processing activity. However, most operating systems (OSs) lack an access control mechanism for CPU resources to guarantee satisfactory processing and to safeguard the system from malicious attacks that affect the CPU resources, resulting in denial of service (DoS). Access control is not intended for general OSs and CPU resources, which are important for the execution of a program. As a result, OSs cannot control the usage ratio of CPU resources. In this paper, we propose an access control model for CPU resources based on an execution resource. The proposed model can control the usage ratio of CPU resources appropriately for each program domain. This execution resource can be applied to mitigate DoS attacks.

An intrusion detection system using alteration of data

Attacks against data in memory are one of the most serious threats these days. Although many detection systems have been proposed so far, most of them can detect only part of alteration. Some detection systems use canaries to detect alteration. However, if an execution code has bugs that enable attackers to read data in memory, the system could be bypassed by attackers who can guess canaries. To overcome the problems, we propose a system using alteration of data. Our proposed system detects illegal alteration with verifier for vulnerable data. Verifier is made before vulnerable data could be altered by attackers, and verifier is checked when the program uses the vulnerable data. Part of verifier is stored in kernel area to prevent attackers from reading data in user memory. Our approach can detect illegal alteration of arbitrary data in user memory. Our proposed system, moreover, does not have the problem systems using canaries have.

I/O Buffer Cache Mechanism Based on the Frequency of File Usage

Most operating systems manage buffer caches for buffering I/O blocks, because I/O processing is slower than CPU processing. Application programs request I/O processing from files. In order to improve the performance of I/O processing, a buffer cache should be managed with regard to both blocks and files. This paper proposes an I/O buffer cache mechanism based on the frequency of file usage. This mechanism calculates the importance of each file. Then, blocks of important files are stored in a protected space. The blocks stored in the protected space are given priority for caching. We evaluated the proposed mechanism by kernel make processing. The results show that the proposed mechanism improves the processing time by 18 s (5.7%) as compared to the LRU algorithm.

Proposal of Instant Synchronous Interprocess Communication

Interprocess communication (IPC) is often applied to cooperative processes and IPC performance largely determine the processing time. Here, we propose an instant synchronous IPC mechanism for preferential processing of high-priority data. In addition, we present that the results of an evaluation using an application program by using an imprecise computational model.

IPS/UMS/WNGS/MUS 2008 Workshop Message from the Workshop Organizers MUE 2008

It is a great pleasure to welcome you to the 2008 IPS/UMS/WNGS/MUS workshop held in conjunction with the International Conference on Multimedia and Ubiquitous Engineering (MUE2008), Hanwha Resort Haeundae, Busan, Korea. The workshop covers topics on ubiquitous multimedia services and security in ubiquitous multimedia systems. All the submitted papers have undergone rigorous review process by the technical program committee members and external reviewers. We have selected 17 best papers for presentation and publication in the conference proceedings.