Here 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.
encrypt MS Access database and also decrypt it.
My purpose is to encrypt the database so that it cannot be open independently without using the application. my application should still be able to access it read/write.
At the moment I have a Form containing two text boxes and two buttons. I want the one textbox to be used to type a message (to be encrypted) and the second textbox will be for a key to decrypt the message. Button one will be for encryption and button 2 for decryption.
View 7 RepliesFrom desktop application I want to upload an image. Then want to pass that image to webservice which encrypt it and pass it to another webservice which will save the encrypted image in the Access database. And then using ASP.net want to decrypt the image.
View 2 RepliesI have a Problem to Decrypt my crypted files :e.g. if I encrypt this text:
B�AR B�LASDJASPDJAPSDJPASDJPASD
asdj
...
And Decrypt it:
AB0_�-M3‚S�r�WPJAPSDJPASDJPASD
asdj
...
The first chars are wrong! My Code to Encrypt and Decrypt :
Encrypt:
Public Shared Sub EncryptFile(ByVal sSource As String, ByVal sTarget As String, Optional ByVal BufferSize As Long = 4096)
Dim ErrorHappened As Boolean = False
Dim OldFileStream As FileStream
Dim NewFileStream As FileStream
[code].....
I need to encrypt a string using javascript and decrypt it using vb.net, is there a compatible encryption/decryption method between javascript and vb.net to be used?
View 5 Replies[Code] I need to do a video encryption/decryption on p2p chat. The concept for my understanding is to capture the video, encode it then encrypt, on the receiver side is to decode and decrypt it.
View 1 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
[Code].....
How to implement encryption and decryption algorithms in vb.net? Which algorithm is the best suited one?
View 4 RepliesI 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 trying to find a simple and easy encryption/decryption method for strings. The strings will contain spaces, special characters, numbers, and letters. I just need to be able to encrypt/decrypt them.
View 3 RepliesI was board making web browsers and OS so, I tried making an Encryption/Decryption program. I surfed the net and found a source code. But, after doing everything, I debug it, click the encrypt btn and nothing happens. I though the encrypting is a slow process. The thing is the process should be immediate cause I downloaded this web browser called 'Areo Pack'. It comes with a few other program and one of them in an Encryption/Decryption program. I tried it and it was done in a few seconds. I tried opening the encrypted file with notepad and I see a text file with Chinese, Japaneses, Korean, etc.
Imports System.Security.Cryptography
Imports System.Text
Public Class Form1
Private Shared DES As New TripleDESCryptoServiceProvider
Private Shared MD5 As New MD5CryptoServiceProvider
[Code] .....
I am trying to make a key that will be used in file encryption/decryption for my application. However, there is no user data involved with this application (As i would usually use the user's password to generate the encryption key), so i have to turn to another method.
I am thinking that maybe it is possible to generate a completely random key the first time the program runs, then save this key inside the program so that it is inaccessible by the user. The user will not be shown this key, but the key MUST be randomly generated for each application, and it also must stay constant once it is created.
Is there a way to encrypt/decrypt text (string form) in VB.net using another string as a key? Meaning, if one user encrypts using this key, the other user needs to decrypt using the same key?I do NOT mean public and private key encryption or anything of the sort.If not, what is the second best way to encrypt/decrypt data without public/private keys?I want to make a simple way to send messages securely.
View 2 RepliesThis is for a simple encryption / decryption program. However when I run this the program does nothing and doesnt respond. Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim decryptedtext As String
Dim encryptedtext As String
Dim k As Int16
[code]...
I'm using the cryptography classes in .net to encrypt and decrypt files. When I encrypt a txt file, then decrypt in my code it works fine. But when I encrypt an xml file and try to decrypt it within my code I get an error saying "padding is invalid and cannot be removed." I am setting the padding during both the encryption and decryption as:
PaddingMode.PKCS7. Do you think the file being an xml file has something to do with the error that's occuring? Also, should I or should I not be setting the padding for both encryption and decryption?
Complete VB project of Image Encryption And Decryption with codes
View 4 RepliesWhat I've decided to start working on is pretty much a personal project but something I may use in my UNI course in due time. I'm creating a security program with a set of access codes (yes I am a bit of a star trek fan) - 4 in total to be exact. I want to be able to use an Encrypted key file in form of a simple notepad created text file to update the codes at any due time. All I'm looking to do is write the access codes to the text file (say for a friend to use the program), Encrypt the file through the program and be able to also decrypt to obtain the new access codes on demand also via the same program. Once decrypted the codes can be read and verified if the user has entered each one correctly. I could hard code the access codes into the program but would rather do it the way I've thought of.
Back in the days of the old VB6 there was a simple method but for some reason that doesnt work any more. What I guess I'm looking to do is have 4 text fields where 4 digit access codes are typed into, have the program take them and encrypt each one is then written to the text file. Hoping that will make it a bit clearer what I'm trying to achieve as I think I made it sound like I want to encrypt the text file after the info has been written to it, which is of course one option so wouldn't mind know how to do that too!
I am trying and failing to make a text encryption and decryption program. How can I encrypt and decrypt text or text files?
View 6 RepliesI have (using some examples) created a program which reads from a file, encrypts the content and writes it to a new file. The file can then be reopened in the program and decrypted.Now I am trying to adapt the program to split the file into pieces as specified by the user whilst it is been written to the hard drive. This also works, but when the files are read and decrypted the original file seems to be corrupted. I have been testing it using a JPG which turns out viewable, but is distorted. However the filesize is the same as the orignal after the encryption/decryption process. [code]
View 3 RepliesI 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 RepliesI'm having trouble writing the code to encrypt a file->networkstream->Decrypt the file.. I've tried several ways, but I keep failing....
View 1 RepliesI've got a site using .netCART. It's running fine in production with Windows Server 2003 and .NET 2.0. On the new server (Windows Server 2008) everything is working except for credit card decryption in the store admin. No errors are being sent, no exceptions thrown, just the encrypted string being output to the screen instead of a decrypted credit card number.
Dim strCCEncrypt As String
strCCEncrypt = Trim(DataRow.Item("CreditCard"))
strCCEncrypt = tools.Decrypt(strCCEncrypt) 'tools is a .netCART utility
[code].....
I 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]...
If the input is alphabets such as any string, it works ok but once the input is in numeric such as "177307" the error attached will be prompted out during the decryption process. I've checked that the decryption value for 177307 is "dw==". I suspected that this function does not support numerical values. Is there anyway to fix this problem? Below are the codes and attached is the error
Imports System
Imports System.Security.Cryptography
Imports System.IO
[code].....
i will like to know if it will be possible to decrypt and encrypted file in vb.net or any without knowing the form of encryption..any information on how to go by it... in that if you lose the form on encryption can it be decrypted?
View 1 RepliesI am actually really new to VB and C#. From numerous tutorials that i found online i was able to create a small program that will encrypt a file. However I am having a really hard time decrying it back.[code]All I am trying to do is to create a program that will decrypte these file with an upload button. Our system encrypts the files to prevent operators from changing the results, we need to trend the data. However it will take way to long to use the online tool provided with the software. A desktop tool will save us much more time. The files generated are 70mb and up.
View 15 RepliesOk so I've made an encrypting/decrypting program and I've found a small bug with it. It will encrypt plain text files fine, except for the last character ( does anyone know how to fix this by the way? ) But when it comes to enrypting PNG Images.. well here's is the before and after files:
[Code]...
i am looking to decrypt my HEX code file for an ATTiny chip and programming it using the AVRDude command line interface. Problem being, i do not want the user to be able to see what the HEX file is at any given time.Can the VB.net Cryptography crypt the HEX file before i put it onto the server and then decrypt it after the program downloads it from the server and runs it through the program without seeing the decrypted HEX file?Obviously the HEX file can not stay encrypted while being programmed to the ATTiny chip so how can i go about it so that i can create the original HEX file to be programmed within the program without having to worry about it writing a temporary file to the hard drive and then deleting it afterwards? (Because they could close the program after it does that temp file and they would be able to navigate and open it and see the code)
View 3 Repliesi am looking to decrypt my HEX code file for an ATTiny chip and programming it using the AVRDude command line interface. Problem being, i do not want the user to be able to see what the HEX file is at any given time.
Can the VB.net Cryptography crypt the HEX file before i put it onto the server and then decrypt it after the program downloads it from the server and runs it through the program without seeing the decrypted HEX file?
Obviously the HEX file can not stay encrypted while being programmed to the ATTiny chip so how can i go about it so that i can create the original HEX file to be programmed within the program without having to worry about it writing a temporary file to the hard drive and then deleting it afterwards? (Because they could close the program after it does that temp file and they would be able to navigate and open it and see the code)