Encrypt (using Rijndael) A String To A File?

Dec 16, 2009

I've attempted using code snippets as a test to encrypt a string, save it to a file & the reload it back, decrypting it. I consistently get a "Padding is invalid and cannot be removed." error on decrypting the string.

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Encrypt Pdf File String?

Feb 4, 2011

I have a page that has a few text boxes on it and are filled based upon a persons information. Like Name, telephone number, address etc

The data is stored in an Access DB.

I want to add a check box and have a label beside it that if it's checked it shows a hyperlink to a pdf file, if its not checked the link disappears, so toggle between the two.

Here's the check box I have so far, which isn't much:

<br><input type=checkbox name="Password" value="<%=oRs("Password")%>" size=40> Check to show PDF File: <a href="<%=oRs("Password")%>"><%=oRs("Password")%></a><br><br>

I need this hyperlink/ string to be encrypted based upon the persons name, so each person has its own pdf file and no one can just guess anothers pdf file and have access to it....

The pdf file will be stored in a virtual directory within the site.

I don't know Vb or asp, and I'm doing this all in notepad ++

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Encrypt And Decrypt Connection String In XML File?

Mar 4, 2010

I want to save my connection string in XML file.How to do that?How to encrypt and decrypt that file using VB.Net

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VS 2005 Encrypt Connection String In ALL Copies Of App.Config File?

Jan 19, 2011

I have a question about the App.Config file. My understanding is that the connection string is stored within this file. I have setup my application so that the App.Config file is not only written to c:users<username>appdatalocal but also to c:users<username>appdataoaming. I plan to encrypt the connection string, my question at this point is will it encrypt the connection string in ALL copies of the App.Config file? It looks like at this point that the App.Config file is stored in two places on the hard drive.

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Decrypt A Datetime.Now.Day String Stored In Registry Using Rijndael

Jun 2, 2012

I recently have been developing a app that uses the rijndael encrypt and decrypt function it stores dates in the registry (encrypted with a key using the algorithm)

for example Dim strOldDay As String = Key.GetValue("UserSettings", "").ToString the key was made using a private function called "createkeys"

example:
dim current as currentdate
Current.Day = DateTime.Now.Day.ToString
Current.Day = Encrypt(pPassPhrase, Current.Day)

[Code]....

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VS 2005 ReEncrypt File In Memory Using Rijndael?

Oct 15, 2009

I have spent quite a while trying to solve this problem.I would like to be able to decrypt a file using an old password, then encrypt the file with a new password in memory. I could easily write the unencrypted file to disk then encrypt the file with a new password, BUT I was trying to keep the unencrypted file from being written to disk. Could someone point me in the right direction?

Private Function ReEncryptFile(ByVal PathToFile As String, ByVal OldPassword As String, ByVal NewPassword As String) As Boolean End Function I've been using a cryptostream to decrypt the file, but I cant seem to figure a way to encrypt the crytostream afterwards (or convert it to a memorystream and (re)encrypt the memorystream)

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.net - Rijndael Encryption Code Is Not Working For Large File?

Oct 1, 2011

I use the following Rijndael code to do encryption without fail for many times. But why it can not encrypt an ISO file with 4.2 GB? In fact my computer has 16GB memory and it should not be a memory problem. I use Windows 7 Ultimate. The code is compiled as winform (.Net 4) using Visual Studio 2010 (a VB.NET project).

I have checked that the ISO file is OK and can be mounted as virtual drive and even can be burnt to DVD rom. So it is not the ISO file problem.My question: Why the following code cannot encrypt an ISO file with size of 4.2GB? Is that caused by the limitation of Windows/.NET 4 implementation?

[Code]...

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Where Is The Proper Location To Embed IV Information For File Encryption Using Rijndael Algorithm?

Sep 29, 2011

I'm creating a Rijndael file encryption application. I will using a unique IV for each file encryption.

My question: Where is the proper place to embed the IV info?

My initial thought is to append it at the end of the file's content. Is that a good choice?

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.net - How To Encrypt A String

May 27, 2012

Parameters.ReferencedAssemblies.Add("System.dll")
Parameters.ReferencedAssemblies.Add("System.Data.dll")
Parameters.ReferencedAssemblies.Add("System.Windows.Forms.dll")

is a way to encrypt "systems.dll" in the add() value?

something like Add(Char64+char45+...) or any method???
Dim Version = New Dictionary(Of String, String)
Version.Add("CompilerVersion", "v2.0")

[Code]...

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How To Encrypt Any Given String

Feb 8, 2011

I made this program to encrypt any given string, I am getting an error that prevents this from being finished.

Public Class Form1
Dim Holder As string
Dim Pass = "Za029fjao"
Dim Helper As String
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Holder = TextBox1.Text
Helper = Holder + Holder * Pass
Textbox2.text = Helper
End Sub
End Class

All I want to do is multiply 2 strings (is that possible?). The error says that string cannot be converted into double...

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AES Encrypt Decrypt String?

Jan 2, 2010

i need a standard way of encrypting a string and decrypting it using AES. I am aware of the Cryptography class, however almost every example creates a class to do the encryption,If .Net already has this implemented and ready to use why would we create classes for encryption and decryption, isn't it as simple as calling the encrypt method of the class or decrpyt and passing in the text. Unless everyone is wanting to centralize the code. But even then i see so many different examples from File,Data Protection etc..

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Encrypt A String Via 128+-bit Encryption?

Apr 23, 2011

I am not sure if there is such thing in VB.NET via 128-bit Encryption or more. [code]...

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Encrypt String In Program?

Dec 12, 2009

Is it possible to encrypt string in VB.NET, so user won't be able to see it, when he opens program with hex editor, or something like that.

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How To Encrypt / Decrypt A String

Nov 2, 2011

how to encrypt / decrypt a string in VB.Net.I followed the example given here and wrote the following code (below). There's a text box, an "encrypt" button, and a "decrypt" button. The idea is to type something into the text box ("like 'hello world'"), click "encrypt", and see the encrypted version appear in the text box. Clicking "decrypt" should then take you back to the original string.

But when I try to encrypt I get an error when I try to "FlushFinalBlock". The error is: "Length of the data to encrypt is invalid".The "decrypt" part is a total shot in the dark, as the example quoted above only deals with encryption, not decryption. I'm sure it's wrong, but since I can't get "encrypt" to work I haven't tested it yet.

Imports System.Data.SqlClient
Imports System.IO
Imports System.Security.Cryptography
Public Class Form1

[code]....

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How To Encrypt Query String

Nov 20, 2010

How to encrypt query string in vb.net ?

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Code For Encrypt / Decrypt String

Nov 12, 2009

i have found a few encrypt/decrypt tutorials online but either they dont work or they only work when the application is running so if i encrypt a string using some code i find and save it (in its encrypted form) and then restart the application and enter the saved encrypted string into a textbox and run the decrypt code it wont decrypt it. i don't understand why en/de-cryption is so hard or why there are so little working examples online. could someone be so kind and show me some code that can let me en/de-crypt a string even if i restart the application or use it on a different computer? and doesn't show the weak key errors all the time.

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Encrypt A String Using AES 256-bit Encryption With A Custom Key

Jul 28, 2009

I need some help with encrypting a string. I want to encrypt a string using AES 256-bit encryption with a custom key. How can I go about doing this?

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Hash - Encrypt A String Using HmacSHA256 In .NET?

May 8, 2009

I need to create a keyed hash for a string of XML to send to a 3rd party. This is the code I am using but it is producing a different hash then the example the 3rd party has sent me.

Public Shared Function HashString(ByVal StringToHash As String) As String
Dim myEncoder As New System.Text.UTF32Encoding
Dim Key() As Byte = myEncoder.GetBytes(My.Settings.PortalHASH)
Dim XML() As Byte = myEncoder.GetBytes(StringToHash)

[code]....

It needs to be base-64 encoded, which is why I have the last line.

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How To Encrypt And Decrypt Password String

Jun 25, 2009

I want to encrypt all users' password that stored in database, but also i need to able to decrypt them.How can i do that?Because i try using MD5 method and only get one way ticket

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[2005] Encrypt String In VB - Decrypt In PHP

Feb 23, 2009

I need to be able to encrypt a string in VB.Net 2005 and then be able to decrypt it using PHP on a web server.

PHP offers a variety of options - the best seeming to be mcrypt() but I can't see (easily) a way of encrypting the string in VB.Net

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Encrypt A String Using RijndaelManaged And Using PKCS5 Padding?

Oct 18, 2010

I use the following code to initialize encryption...

[Code]...

So I don't think there is a method for PKCS5. Is there any way to add it, or do I need to write an encryption method myself? If so - how do I write that? Is there a reliable DLL that will support it?

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VS 2008 - Encrypt String Using ECDSA Algorithm?

May 28, 2009

Any example code to encrypt a string using the new ECDSA algorithm?

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Vb 2005 : Encrypt The String Values Stored In The Code?

Jul 23, 2009

encrypt the string values stored in the code.The problem is that when the code is compiled and the .exe file is generated, anybody can edit the .exe file with an text editor or another program and see the values.This is very important for me, because i have some password stored in string variables?

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VB 2008 App - Encrypt Database Connection String In App.Config

Sep 21, 2011

I know this topic has been addressed a million times but please help me out. I have read so many articles on HOW TO encrypt and decrypt the app.config file but I need to know WHEN and WHERE I should encrypt it.

The problem arose because we found an AppName.exe.config file on a users computer and the database username and password was clearly visible. I understand that the .config file gets created during the VB app install process and is used
by the application. I then learned about the aspnet_regiis.exe tool and ran it on the app.config file inside my VB project. I am guessing that was the wrong thing to do.

When I now install the app on user desktops, it gives an error stating failed to decrypt the connection string. Also, when one of my other developers attempts to open the project in his copy of visual studio on his computer, he receives an error when trying to access the setting portion of the project properties. We store all of our projects on a file server and any developer can access the projects via a mapped drive on their computer.

So how am I supposed to encrypt the .config file. If I can't encrypt the App.config file in the development environment, then I'm guessing I have to perform the encryption on the users PC during the install process? How do I do that? Or is that what I am supposed to do?

Just for reference, here is the aspnet_regiis command I ran.

aspnet_regiis.exe -pef "connectionStrings" S:ProjectsDevelopmentVB.netPTPUSourceCodePTPU -prov "DataProtectionConfigurationProvider"

One last thing, maybe it's my misunderstanding of the issue but if this problem has existed since .Net 2.0, why has an option not been built into the development studio to encrypt connection strings?. This would seem to be a very common issue, even their own dataset wizard creates connection strings that are clearly readable.

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Encryption/Decryption - Code To Encrypt A File->networkstream->Decrypt The File

Feb 28, 2011

I'm having trouble writing the code to encrypt a file->networkstream->Decrypt the file.. I've tried several ways, but I keep failing....

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VS 2005 Possible To Be Able To Encrypt File / Have Application Be Able To Decrypt It And Amend File As Necessary

Mar 17, 2009

I would like to know if it is possible to be able to encrypt a file and have my application be able to decrypt it and ammed the file as necessary. and then when the program exits it will encrypt the file back up.

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Encrypt A File With RSA In VB?

Oct 16, 2009

I'm just getting started with Visual Basic .NET and I'm currently stuck on the following problem: how can I encrypt/decrypt a file with asymmetric encryption?

Essentially, I'm trying to figure out how I can write the following pseudocode in VB

[code]...

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VS 2005 File.encrypt And File.decrypt

Mar 12, 2010

Has anyone used these methods? I tried File.Encrypt on a text file, and I did not get an exception, however the Encrypt method did not work (the file was unchanged afterwards).

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Encrypt / Decrypt Xml File

Jun 22, 2011

I need some help on saving/reading xml from/to dataset. I would like to make that complete file is encrypted and not only some elements inside or part of file.Currently this is not working in any way at all.[code]

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Encrypt A File Then Read It?

Apr 14, 2010

So I have a connection string which is read from a basic text file. This string contains a password. Is there anyway to encrypt this text file so that anyone can't just open it up and read it. The program will still be able to read it.

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