Fastest Hash Function For Hashing Filenames?

Feb 9, 2010

I'm trying to optimize my ASP.NET thumbnailing script, so it doesn't resize all the images all the time, and one part of the problem is choosing the hash function for the thumbnail naming/checking procedure.Is crc32 up to the task - I'm asking cause the input data is small(only relative path, size and date)?

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E.g.

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I have number of files stored in a folder.

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[Code]....

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[Code]....

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I'm using Webservice which will return the data from the database through datatable and I'll convert the datatable into byte array. In front end, I'll reconvert the bytearray to datatable and used ajaxloader to display it in the form.. It is dynamic loading. So, for each click, it is taking 10 seconds to retreive the data regardless of the size of the data. So, I used static datatable and I've loaded all data in that datatable in page load event. But, no reaction. It is taking only same time. Even, there is no data to retreive, the ajax loader is going on loading for 10 seconds. Problem is with Ajax or my webservice?? Plz, tell me some other idea??!!

[Code]....

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I am trying to run a linq query but I need the result as a datatable as I am using that to store records from different queries in the same viewstate object.The 2 versions below compile, but return an empty set. The exact error is "Value cannot be null.Parameter name: source". (and yes I have checked there is data):

MyDatabaseDataContext db = new MyDatabaseDataContext(conn);
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[code]...

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I'm just wondering if the built in Hashing in the ASP.Net membership good password security, or if there is more that I should do to protect my passwords? If so, what should I look into for a higher level of security?

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C# - SHA1 + Salt Password Hashing On Multiple Servers

Feb 8, 2011

So, I am the approach David Hayden posted on his blog [URL] to create a salt and hash the user's password by taking the user's raw password and the generated salt and using SHA1 to hash the value. I then store the salt and the hashed password in the database. zhe website is currently load balanced, so I was wondering if resulting hash value would be the same for both servers. Here is the snippet of code posted on David Hayden's blog:

private static string CreateSalt(int size)
{
//Generate a cryptographic random number.
RNGCryptoServiceProvider rng = new RNGCryptoServiceProvider();
byte[] buff = new byte[size];
rng.GetBytes(buff);
// Return a Base64 string representation of the random number.
return Convert.ToBase64String(buff);
}

private static string CreatePasswordHash(string pwd, string salt)
{
string saltAndPwd = String.Concat(pwd, salt);
string hashedPwd =
FormsAuthentication.HashPasswordForStoringInConfigFile(
saltAndPwd, "sha1");
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}

The reason I ask is that this code uses the code snippet: FormsAuthentication.HashPasswordForStoringInConfigFile(saltAndPwd, "sha1");

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Jan 5, 2010

I am planning to write a custom 'password reset control' that allows an Administrator to reset the user's password, while using the ASP.NET built-in 'login' and 'create new user' controls. For this reason, I will need the hashing algorithm (hopefully I can call some .NET class and method) to perform this.

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Security :: Hashing Web.config Credentials / Connection Strings

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I want to apply some better security measures to an existing web application. Currently, my connection string contains the user name and password in plain text. I'm also using a custom membership provider, which stores user names and passwords in the web.config file as plain text [URL] I would like to secure this information using an algorithm such as SHA1.

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