My current approach of using Rijndael is to use a pair of static Key and Iv for all encryption operations (I mean I use this pair of Key and Iv for all protected files in my computer).
I heard that IV must be unique for each Rijndael encryption. Is that true? What is the problem (if any) for my current approach of using single static Key and Iv pair?
At first i thought it was the padding since mcrypt uses zero padding but i changed the php to use PKCS7 and get the same exact results.I think it has something to do with the padding in the php.Test output from .Net:
Key: d88f92e4fa27f6d45b49446c7fc76976
Text: Testing123
Encrypted: /DMkj7BL9Eu2LMxKhdGT+A==[code]......
I am using a slightly modified version of this code. to create a mission critical application. That files that will be encrypted are very important. This has to be done from scratch because there are some other things that has to be done along with this. How secure is this? Its impossible to crack this encryption right? [Code]
View 2 RepliesI 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?
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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?
I want it to do is that you input a string, then you select an algorithm (Theres only going to be one RijnDael) then you input a key, then the Initialization Vector comes from "txtIV.text" then you select the key bytes and the block bytes from the numeric up/down, then you either encrypt or decrypt.
View 1 RepliesAt the moment I have a piece or code that encripts a messasage and writes it to a textbox and a external text file. BUT the problem I have is that it is static and that every time a encript something it will do it exactley the same and I want it to be random. This is what I have so far: This is my form:
[code]...
my program takes a txt file and encrypts it successfully but it returns the wrong thing when decryting.[code]
View 4 RepliesWhen I decrypt an encrypted file; it doesn't have the same size in bytes as the original file and the the hash of the file is different.
I get the bytes of the file using File.ReadAllBytes and send to EncryptBytes with the password. Also the same with DecryptBytes.
When I receive the bytes encrypted or decrypted i save them using File.WriteAllBytes.
I need that the decrypted file and original file have the same hash an bytes.
This my code:
Public Function EncryptBytes(ByVal pass As String, ByVal bytes() As Byte)
Dim myRijndael As New RijndaelManaged
myRijndael.Padding = PaddingMode.Zeros
myRijndael.KeySize = 256
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I need to encrypt an XML file, send it to another location and decrypt it there. As you can see from the codes below, I am using the same key but it won't work (for now im simply using two local files).
The error I get is as follows:
Padding is invalid and cannot be removed.on this line in Decrypt.aspx: Dim xReader As XmlTextReader I am thinking it might be at the actual encryption stage causing errors e.g., file not saving correctly.
Encrypt.aspx
Dim rijnAlg As RijndaelManaged
rijnAlg = RijndaelManaged.Create()
[code]......
I'm designing a program to encrypt and decrypt files using TripleDes Encryption algorithms but am having issues decrypting an image file. The file encrypts in the correct manner, but when I go to decrypt the file and open as an image I get an error message. One example is when trying to open the file in paint a message appears stating 'c:New FolderDecrypted.jpg Paint cannot read this file. This is not a valid bitmap file, or its format is not currently supported. My coding for the form is shown below:
"Imports System.Windows.Forms
Imports System.Security.Cryptography
Imports System.Security
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I'm trying to host some static files for access by an ASP.Net web role and a separate data worker role that are both running on the same deployment (they use a global static interface).
However, I'm unsure how exactly to 'host' them, I've tried using virtual folders via HttpRuntime.AppDomainAppPath, but it only occasionally works in debug mode. The files also don't seem to get packaged into the deployment packages made by VS vis CSPack (though this might be a separate issue, is it possible to fix this too?)
The static files in question are actually WordNet, which I'm using through WordNet.Net, If that makes any difference. I also need the solution to work in both the cloud deployment and the emulator (if possible).
i have created a VB.net application which can be used as a BO scheduler substitute for sending refreshed report copies. These copies are AES 256 encrypted and password protected.
View 2 RepliesI have set up a method in vb.net and in xcode for encrypting a string using as far as i can tell the same parameters for an AES encryption.I've looked all over the place but cannot find information on whether they use the same encryption algorithm and settings.
this is the vb.net code:
Dim encryptAES As New AesCryptoServiceProvider()
Dim encoding As New UTF8Encoding()
Dim encryptor As ICryptoTransform
encryptAES.Key = encoding.GetBytes("12345678901234567890123456789032")
encryptAES.IV = encoding.GetBytes("1234567890123416")
encryptAES.Mode = CipherMode.CBC
[Code]...
How to generate Rijndael KEY and IV using a passphrase? The key length must be in 256 bits.
View 5 RepliesI'm trying out the Rijndael to generate an encrypted license string to use for our new software, so we know that our customers are using the same amount of apps that they paid for.[code]...
View 3 RepliesI'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.
View 3 RepliesIm using Rijndael (as AES algorithm) for encrypting. I encrypt the values (objects properties) and serialize the object to xml an dsend the xml to the receiver via a web service. I want to pass along the encrypted symmetric key that I used to encrypt the data. But what key should I pass along?
My decryption algorithm looks like this (vb.net):
CODE:
If I want to decrypt the encrypted string I have to use both key and IV, but I think I have to pass along only a key value. Do I have to do this another way or what should I pass along? My specification says that the values have to be encrypted using AES and a 128 bits key.
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)
What's the difference? I'm going to create a password encrypting program, and I wanted to know what's the basic difference about the managed class and the "not managed" class.
View 4 RepliesDo both of these algorithm work only with a 128bit size block size?
View 3 RepliesI 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)
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is there anyway that I can convert this to use RSA encryption?
Imports System.Text
Imports System.Security.Cryptography
Imports System.IO
Public Class ClsEncryption
[code].....
I have been trying to create an app that will do xor encryption. I have tried a few different functions but none of them seem to give me what I want. I need it to put the coded text into a 7 bit ascii string. For example if the key was a - 1100001 and the text to be encrypted was s - 1110011 then it would return 0010010 as the encryption. One of the pieces of code I tried to use
Public Function XOREncryption(ByVal CodeKey As String, ByVal DataIn As String) As String
Dim lonDataPtr As Long
Dim strDataOut As String
Dim temp As Integer
[code]....
This returns a hex digit though which will not work for what I want.
have made a library for my vb.net project by combining 3 libraries (using ilmerge).
View 3 RepliesI am attempting to create a program that can do raw RSA encryption (performing the encryption without using 'Encrypt' and 'Decrypt') of a user's message that can contain a-z, A-Z, 0-9, and [,.;:'"()]. I've attached a screen shot of the application form.
Basically, the user will pick from a list of prime numbers from the first box and input them into p and q. They will type their message in the designated textbox and then hit <encrypt> which will encrypt using p and q and then show the encrypted message below. I'll leave out the Key box since that deals with the math behind the encryption.
The part I am stuck on right now is assigning a number to each one of the characters so that it can be encrypted. These numbers need to remain the same so that the message can be decrypted as well.
I am rewriting a C# class in VB. The C# class has a static constructor in it:
static Class()
{
...
}
which, through the Call Stack, I found is called by the main window's InitializeComponent() method.Everywhere I've looked has told me that the corresponding static constructor in VB is just:Shared Sub New()
but this method is never invoked. Am I creating my VB static constructor right? Is it likely something else that has nothing to do with my static constructor?
I am writing a code for a webapplication in vb.net. I am using a shared variable in the vb code.
Consider the static variable value is 3 for a user who hits the web application. Again when another user hits the same web application, whether the static variable will be 3 again or whether he will have a separate value for static variable for his session?
i have this .xml file read and display at runtime by vb.net2003. the .xml file is the database which contain various data and its not for adding more data or edited by user so i need to protect the file so that my code can read and display those data. can anyone know how to protect the file.
View 1 RepliesHere is some code that works well for strings:
[Code]....
modifying these functions to encrypt/decrypt byte arrays rather than strings. Also, to have the functions return the encrypted/decrypted byte array, rather than a string.