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Bahman Rashidi
Description DroidCat logger is a software package developed to instrument Android applications and capture their log activities. The main merit of DroidCat is that it can instrument apps through real human-­interaction, so we can get... more
Description DroidCat logger is a software package developed to instrument Android applications and capture their log activities. The main merit of DroidCat is that it can instrument apps through real human-­interaction, so we can get behavior logs which highly assemble real world executing of Android apps. DroidCat Logger has been developed for XDroid project. You can find more details on the tool in the paper. Download Policy We are pleased to share this package, but in order to prevent any misuse, we ask you to send us an email to rashidib@vcu.edu. We will email you back the package. ­ If you are in academia:
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The dataset contains 950 Android application logs from different malware categories. Applications are instrumented by human (real human-interaction) so the behavior logs highly assemble real world executing of Android apps. The dataset... more
The dataset contains 950 Android application logs from different malware categories. Applications are instrumented by human (real human-interaction) so the behavior logs highly assemble real world executing of Android apps. The dataset contains 440 malicious and 508 benign (normal) app logs. The logs have been captured for XDroid project. You can find more details on the dataset in the paper.
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Research Interests:
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—RecDroid is a smartphone permission management system which provides users with a fine-grained real-time app permission control and a recommendation system regarding whether to grant the permission or not based on expert users' responses... more
—RecDroid is a smartphone permission management system which provides users with a fine-grained real-time app permission control and a recommendation system regarding whether to grant the permission or not based on expert users' responses in the network. However, in such a system, malware owners may create multiple bot users to misguide the recommendation system by providing untruthful responses on the malicious app. Threshold-based detection method can detect malicious users which are dishonest on many apps, but it cannot detect malicious users that target on some specific apps. In this work, we present a clustering-based method called BotTracer to finding groups of bot users controlled by the same masters, which can be used to detect bot users with high reputation scores. The key part of the proposed method is to map the users into a graph based on their similarity and apply a clustering algorithm to group users together. We evaluate our method using a set of simulated users' profiles, including malicious users and regular ones. Our experimental results demonstrate high accuracy in terms of detecting malicious users. Finally, we discuss several clustering features and their impact on the clustering results.
Research Interests:
With billions of people using smartphones and the exponential growth of smartphone apps, it is prohibitive for app marketplaces, such as Google App Store, to thoroughly verify if an app is legitimate or malicious. As a result, mobile... more
With billions of people using smartphones and the exponential growth of smartphone apps, it is prohibitive for app marketplaces, such as Google App Store, to thoroughly verify if an app is legitimate or malicious. As a result, mobile users are left to decide for themselves whether an app is safe to use. Even worse, recent studies have shown that over 70% of apps in markets request to collect data irrelevant to the main functions of the apps, which could cause leaking of private information or inefficient use of mobile resources. It is worth mentioning that since resource management mechanism of mobile devices is different from PC machines, existing security solutions in PC malware area are not quite compatible with mobile devices. Therefore, academic researchers and commercial anti-malware companies have proposed many security mechanisms to address the security issues of the Android devices. Considering the mechanisms and techniques which are different in nature and used in proposed works, they can be classified into different categories. In this survey, we discuss the existing Android security threats and existing security enforcements solutions between 2010-2015 and try to classify works and review their functionalities. We review a few works of each class. The survey also reviews the strength and weak points of the solutions.
Research Interests:
With the exponential growth of smartphone apps, it is prohibitive for apps market places, such as Google App Store for example, to thoroughly verify if an app is legitimate or malicious. As a result, mobile users are left to decide for... more
With the exponential growth of smartphone apps, it is prohibitive for apps market places, such as Google App Store for example, to thoroughly verify if an app is legitimate or malicious. As a result, mobile users are left to decide for themselves whether an app is safe to use. Even worse, recent studies have shown that most apps in markets request to collect data irrelevant to the main functions of the apps, which could cause leaking of private information or inefficient use of mobile resources. To assist users to make a right decision as for whether a permission request should be accepted, we propose RecDroid. RecDroid is a crowdsourcing recommendation framework that collects apps' permission requests and users' permission responses, from which a ranking algorithm is used to evaluate the expertise level of users and a voting algorithm is used to compute an appropriate response to the permission request (accept or reject). To bootstrap the recommendation system, RecDroid relies on a small set of seed expert users that could make reliable recommendations for a small set of application. Our evaluation results show that RecDroid can provide high accuracy and satisfying coverage with careful selection of parameters. The results also show that a small coverage from seed experts is sufficient for RecDroid to cover the majority of the app requests.
Research Interests:
RecDroid is an Android smartphone permission control framework which provides fine-grained permission control regarding smartphone resources and recommends the permission control decisions from savvy users to inexperienced (novice) users.... more
RecDroid is an Android smartphone permission control framework which provides fine-grained permission
control regarding smartphone resources and recommends the permission control decisions
from savvy users to inexperienced (novice) users. However, malicious users, such as dummy users
created by malicious app owners, may attempt to provide untruthful responses in order to mislead the
recommendation system. Although a sybil detection function can be used to detect and remove some
dummy users, undetected dummy users may still be able to mislead RecDroid framework. Therefore,
it is not sufficient to depend on sybil detection techniques. In this work, we investigate this
problem from a game-theoretical perspective to analyze the interaction between users and RecDroid
system using a static Bayesian game-theoretical formulation. In the game, both players choose the
best response strategy to minimize their loss in the interactions. We analyze the game model and find
both pure strategy Nash equilibrium and mixed strategy Nash equilibrium under different scenarios.
Finally, we discuss the impact from several parameters of the designed game on the outcomes, and
analyzed the strategy on how to disincentivize attackers through corresponding game design.
Research Interests:
The rapid growth of smartphone application market raises security concerns regarding untrusted applications. Studies have shown that most apps in markets request to collect data irrelevant to the main functions of the apps. Traditional... more
The rapid growth of smartphone application market raises security concerns regarding untrusted applications. Studies have shown that most apps in markets request to collect data irrelevant to the main functions of the apps. Traditional permission control design based on one-time decisions on installation has been proven to be not effective to protect user privacy and poorly utilize scarce mobile resources (e.g. battery). In this work, we propose RecDroid, a framework for smartphone users to make permission control in real time and receive recommendations from expert users who use the same apps. This way users can benefit from the expert opinions and make correct permission granting decisions. We describe our vision on realizing our solution on Android and show that our solution is feasible, easy to use, and effective.
Research Interests:
RecDroid is a smartphone permission response recommendation system which utilizes the responses from expert users in the network to help inexperienced users. However, in such system, malicious users can mislead the recommendation system... more
RecDroid is a smartphone permission response recommendation system which utilizes the responses from expert users in the network to help inexperienced users. However, in such system, malicious users can mislead the recommendation system by providing untruthful responses. Although detection system can be deployed to detect the malicious users, and exclude them from recommendation system, there are still undetected malicious users that may cause damage to RecDroid. Therefore, relying on environment knowledge to detect the malicious users is not sufficient. In this work, we present a game-theoretic model to analyze the interaction (request/response) between RecDroid users and RecDroid system using a static Bayesian game formulation. In the game RecDroid system chooses the best response strategy to minimize its loss from malicious users. We analyze the game model and explain the Nash equilibrium in a static scenario under different conditions. Through the static game model we discuss the strategy that RecDroid can adopt to disincentivize attackers in the system, so that attackers are discouraged to perform malicious users attack. Finally, we discuss several game parameters and their impact on players' outcome.
Research Interests:
Computer Science, Game Theory, Information Security, Computer Engineering, Privacy, and 40 more
Nowadays, it is prohibitive for apps market places, such as google App Store, to thoroughly verify an app’s resource permission requests to be legitimate or malicious. As a result, mobile users are left to decide for themselves whether... more
Nowadays, it is prohibitive for apps market places, such as google App Store, to thoroughly verify an app’s resource  permission requests to be legitimate or malicious. As a result, mobile users are left to decide for themselves whether an app is safe to use or not. To assist users to make correct decisions as for whether to accept a permission request or not, we propose RecDroid. RecDroid is a crowdsourcing  recommendation framework that collects apps’ permission requests and users’ responses to those requests, from
which an experts ranking algorithm is used to seek expert users in the system and a recommendation algorithm is used to suggest appropriate responses to permission requests (accept or reject) based on experts’ responses. In this demo, we demonstrate a user case to show how the RecDroid system assists users in permission control. We also explain the major principles and processes behind that support the RecDroid recommendation system.
Research Interests:
Computer Science, Information Security, Computer Engineering, Privacy, Recommender Systems, and 35 more
In the recent years, Cloud Computing has been one of the top ten new technologies which provides various services such as software, platform and infrastructure for internet users. The Cloud Computing is a promising IT paradigm which... more
In the recent years, Cloud Computing has
been one of the top ten new technologies which provides
various services such as software, platform and
infrastructure for internet users. The Cloud Computing is
a promising IT paradigm which enables the Internet
evolution into a global market of collaborating services.
In order to provide better services for cloud customers,
cloud providers need services that are in cooperation
with other services. Therefore, Cloud Computing
semantic interoperability plays a key role in Cloud
Computing services. In this paper, we address
interoperability issues in Cloud Computing
environments. After a description of Cloud Computing
interoperability from different aspects and references,
we describe two architectures of cloud service
interoperability. Architecturally, we classify existing
interoperability challenges and we describe them.
Moreover, we use these aspects to discuss and compare
several interoperability approaches.
Research Interests:
This paper presents the methods to reduce dynamic power consumption of a digital Finite Imppulse Respanse (FIR) filter these mrthods include low power serial multiplier and serial adder, combinational booth multiplier, shift/add... more
This paper presents the methods to reduce dynamic
power consumption of a digital Finite Imppulse Respanse (FIR)
filter these mrthods include low power serial multiplier and
serial adder, combinational booth multiplier, shift/add
multipliers, folding transformation in linear pheas
architecture and applied to fir filters to power consumption
reduced thus reduce power consumption due to glitching is
also reduced. The minimum power achieved is 110mw in fir
filter based on shift/add multiplier in 100MHZ to 8taps and
8bits inputs and 8bits coefficions. The proposed FIR filters
were synthesized implemented using Xilinx ISE Virtex IV
Research Interests:
In last two decades continues increase of comput-ational power and recent advance in the web technology cause to provide large amounts of data. That needs large scale data processing mechanism to handle this volume of data. MapReduce is a... more
In last two decades continues increase of comput-ational power and recent advance in the
web technology cause to provide large amounts of data. That needs large scale data
processing mechanism to handle this volume of data. MapReduce is a programming model
for large scale distributed data processing in an efficient and transparent way. Due to its
excellent fault tolerance features, scalability and the ease of use. Currently, there are several
options for using MapReduce in cloud environments, such as using MapReduce as a service,
setting up one’s own MapReduce cluster on cloud instances, or using specialized cloud
MapReduce runtimes that take advantage of cloud infrastructure services. Cloud computing
has recently emerged as a new paradigm that provide computing infrastructure and large
scale data processing mechanism in the network. The cloud is on demand, scalable and high
availability so implement of MapReduce on the top of cloud services cause faster, scalable
and high available MapReduce framework for large scale data processing. In this paper we
explain how to implement MapReduce in the cloud and also have a comparison between
implementations of MapReduce on AzureCloud, Amazon Cloud and Hadoop at the end.
Research Interests:
This paper presents, complete step by step description design and implementation of a high speed technique for character segmentation of license plate based on thresholding algorithm. Because of vertical edges in the plate, fast Sobel... more
This paper presents, complete step by step
description design and implementation of a high speed
technique for character segmentation of license plate
based on thresholding algorithm. Because of vertical
edges in the plate, fast Sobel edge detection has been
used for extracting location of license plate, after stage
edge detection the image is segmented by thresholding
algorithm and the color of characters is changed to white
and the color of background is black. Then, boundary’s
pixels of license plate are scanned and their color is
changed to black pixels. Afterward the image is scanned
vertically and if the number of black pixels in a column
is equal to the width of plate or a little few, then the
pixels of that column is changed to white pixel, until
create white columns between characters, in continue
we change pixels around license plate to white pixels.
Finally characters are segmented cleanly. We test
proposed character segmentation algorithm for stage
recognition of number by code that we design. Results
of experimentation on different images demonstrate
ability of proposed algorithm. The accuracy of proposed
character segmentation is 99% and average time of
character segmentation is 15ms with thresholding
algorithm code and 0.7ms only segmentation character
code that is very small in comparison with other
algorithms.
Research Interests:
Electrical Engineering, Electronic Engineering, Computer Science, Computer Architecture, Computer Graphics, and 25 more
This paper presents, a low power 128-bit Advanced Encryption Standard (AES) algorithm based on a novel asynchronous self-timed architecture for encryption of audio signals. An asynchronous system is defined as one where the transfers of... more
This paper presents, a low power 128-bit
Advanced Encryption Standard (AES) algorithm based
on a novel asynchronous self-timed architecture for
encryption of audio signals. An asynchronous system is
defined as one where the transfers of information
between combinatorial blocks without a global clock
signal. The self-timed architectures are asynchronous
circuits which perform their function based on local
synchronization signals called hand shake, independently
from the other modules. This new architecture reduced
spikes on current consumption and only parts with valid
data are working, and also this design does not need any
clock pulse. A combinational logic based Rijndael S-Box
implementation for the Substitution Byte transformation
in AES is proposed, its low area occupancy and high
throughput therefore proposed digital design leads to
reduction in power consumption. Mix-columns
transformation is implemented only based on multiplyby-2
and multiply-by-3 modules with combinational logic.
The proposed novel asynchronous self-timed AES
algorithm is modeled and verified using FPGA and
simulation results from encryption of sound signals is
presented, until original characteristics are preserved
anymore and have been successfully synthesized and
implemented using Xilinx ISE V7.1 and Virtex IV FPGA
to target device Xc4vf100. The achieved power
consumption is 283 mW in clock frequency of 100 MHz
Research Interests:
In this paper, presents an optimized combinational logic based Rijndael S-Box implementation for the SubByte transformation(S-box) in the Advanced Encryption Standard (AES) algorithm on FPGA. S-box dominated the hardware complexity of the... more
In this paper, presents an optimized
combinational logic based Rijndael S-Box
implementation for the SubByte transformation(S-box) in
the Advanced Encryption Standard (AES) algorithm on
FPGA. S-box dominated the hardware complexity of the
AES cryptographic module thus we implement its
mathematic equations based on optimized and
combinational logic circuits until dynamic power
consumption reduced. The complete data path of the Sbox
algorithm is simulated as a net list of AND, OR,
NOT and XOR logic gates, also for increase in speed and
maximum operation frequency used 4-stage pipeline in
proposed method. The proposed implemented
combinational logic based S-box have been successfully
synthesized and implemented using Xilinx ISE V7.1 and
Virtex IV FPGA to target device Xc4vf100. Power is
analized using Xilinx XPower analyzer and achieved
power consumption is 29 mW in clock frequency of 100
MHz. The results from the Place and Route report
indicate that maximum clock frequency is 209.617 MHz.
Research Interests:
In this paper, the authors present implementation of a low power and low area digital Finite Impulse Response (FIR) filter. The we method for reduce dynamic power consumption of a digital FIR filter is use of low power multiplexer based... more
In this paper, the authors present implementation
of a low power and low area digital Finite Impulse Response
(FIR) filter. The we method for reduce dynamic power
consumption of a digital FIR filter is use of low power
multiplexer based on shift/add multiplier without clock pulse
and we applied it to fir filter until power consumption reduced
thus reduce power consumption due to glitching is also reduced.
The minimum power achieved is 56mw in fir filter based on
shift/add multiplier in 100MHZ with 8bits inputs and 8bits
coefficients. The proposed FIR filter was synthesized
implemented using Xilinx ISE V7.1 and Virtex IV FPGA to
target device xc4vlx200 also power is analized using Xilinx
XPower analyzer.
Research Interests: