Guarantee Effective osearchmsearchlsearch search omsearchlsearch Entertain ssearcha Study cd Study e Study rsearchhs Szh a Formula c Effective F Effectivestudyformula r Effective ula Study tdy 2010 nsearchE Study fc Formula i Study et Study dfsearchr Formula usearchasearchs
Abstract: Side channel attacks on cryptographic systems are attacks exploiting information gained from physical implementations rather than utilizing theoretical weaknesses of a scheme. In particular, during the last years, major achievements were made for the class of access-driven cache-attacks. The source of information leakage for such attacks are the locations of memory accesses performed by a victim process.
In this paper we analyze the case of AES and present an attack which is capable of recovering the full secret key in almost realtime for AES-128, requiring only a very limited number of observed encryptions. Unlike most other attacks, ours neither needs to know the ciphertext, nor does it need to know any information about the plaintext (such as its distribution, etc.). Moreover, for the first time we also show how the plaintext can be recovered without having access to the ciphertext. Further, our spy process can be run under an unprivileged user account. It is the first working attack for implementations using compressed tables, where it is not possible to find out the beginning of AES rounds any more -- a corner stone for all efficient previous attacks. All results of our attack have been demonstrated by a fully working implementation, and do not solely rely on theoretical considerations or simulations.
A contribution of probably independent interest is a denial of service attack on the scheduler of current Linux systems (CFS), which allows to monitor memory accesses with novelly high precision. Finally, we give some generalizations of our attack, and suggest some possible countermeasures which would render our attack impossible.

Read more: eprint
Posted via email from .NET Info
Delicious Twitter Facebook Digg Stumbleupon Technorati RSS
Links to this post

HowTo: Open MSTest with MSBuild

0 comments
According to the blogpost about „HowTo: build solutions with MSBuild“ I’m going to show you a little example about how to call MSTests.

Scenario
The structure is nearly the same like in this blogpost. As a little add-on I created a new test project:


I’ve added one more “RunTests” target to my BuildSolutions.target file where the MSBuild Script is included:

<Project xmlns="developer/msbuild/2003" DefaultTargets="Build">

<PropertyGroup>
<OutDir>$(MSBuildStartupDirectory)\OutDir\</OutDir>
<SolutionProperties>
OutDir=$(OutDir);
Platform=Any CPU;
Configuration=Release
</SolutionProperties>
</PropertyGroup>
<ItemGroup>
<Solution Include="..\MsBuildSample.sln">
<Properties>
$(SolutionProperties)
</Properties>
</Solution>
</ItemGroup>
<Target Name="Build">
<MSBuild Projects="@(Solution)">
</Target>
<Target Name="RunTests">
<Exec Command='"C:\Program Files (x86)\Microsoft Visual Studio 10.0\Common7\IDE\mstest.exe" /testcontainer:"$(MSBuildStartupDirectory)\OutDir\MsBuildSample.WebApp.Tests.dll" /testcontainer:"$(MSBuildStartupDirectory)\OutDir\AnotherTestProject.dll"' />
</Target>
</Project>

Read more: Code-Inside Blog International
Posted via email from .NET Info
Delicious Twitter Facebook Digg Stumbleupon Technorati RSS
Links to this post

How to consume a web service from within SQL Server using SQL CLR

0 comments
DISCLAIMER:
This is just intended as proof of concept. I do feel that if you wish to consume web services from SQL Server, then you should probably put this code in an assembly outside SQL Server and then call that assembly from the CLR within SQL Server. This will make it more maintainable when, for example, the web service changes. If you then need to rebuild the references etc., it will be easier to do this in an external assembly rather than in assemblies stored in SQL Server.
In this scenario we have a web service that return the current temperature for the provided city. We wish to consume this information from within SQL Server and store it in a table. Let’s do this from scratch.

Step 1 is to create the web service itself.
In Visual Studio, create a new ASP.Net Web Service project in a web site (called Weather in this example) call it “WeatherService”.
Delete the default WebMethod and create a new one that will return the temperature for provided city. Call this method “GetTemperatureForCity”.

Read more: Common tips and tricks from a SQL Developer Support perspective
Posted via email from .NET Info
Delicious Twitter Facebook Digg Stumbleupon Technorati RSS
Links to this post

Scrypt Enhanced Cryptography for Silverlight 3+

0 comments
Project Description
The Scrypt enahnced cryptography library provides additional cryptographic capabilities for Microsoft Silverlight 3+. In this initial release we've added RSA Encryption with support for key sizes from 256-bit to 4096-bit.

This library is fully compatible with .NET's built in RSACryptoServiceProvider.

For some usage examples, please visit my blog:
post/Asymmetric-Encryption-and-Signing-with-RSA-in-Silverlight.aspx

Limitations
This library limits the allowed key size to the range of 256-bit to 4096-bit. This is strictly due to the functionality of the employed BigInteger class that is used which initializes a fixed array for data storage. While this size can be increased to allow for larger keys, I found the negative impact on performance to be unacceptable. Likewise, I performed a full conversion of the BigInteger class to utilize generics instead of fixed arrays but the performance impact of this approach was also unacceptable.

Read more: Codeplex
Posted via email from .NET Info
Delicious Twitter Facebook Digg Stumbleupon Technorati RSS
Links to this post

Difference between int.Parse and Convert.ToInt32