Key - Decrypt A SHA1 String
Jan 26, 2011Is it possible to decrypt a SHA1 string in VB.Net, knowing the key? I have seen "decryption" of credentials before, however - in Java: [URL]
View 3 RepliesIs it possible to decrypt a SHA1 string in VB.Net, knowing the key? I have seen "decryption" of credentials before, however - in Java: [URL]
View 3 Repliesi 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..
View 10 RepliesThere is a problem with the source code. I cannot convert the string to decrypt from encrypt string.[code]I went on breakpoint on that line and I have looked on quickwatch. The error I have caught is that convert is a type and cannot be used as an expression.
View 18 Replieshow 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]....
I can encrypt a string with this code. It works fine.
Imports Microsoft.VisualBasic
Imports System.IO
Imports System.Security.Cryptography
[Code]......
But i am not able to decrypt the string i am using this code to decrypt. It gives error that Padding is invalid and can not be removed.
Imports Microsoft.VisualBasic
Imports System.Security.Cryptography
Imports System.IO
[Code].....
I am retrieving lists of crc32 hashes that contain names of files, not there contents.I need to be able to decrypt the strings which are hashed names like "vacationplans_2010.txt" which are less then 25 characters long.
View 3 Repliesi 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.
View 3 RepliesI 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
View 4 RepliesI 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
I want to save my connection string in XML file.How to do that?How to encrypt and decrypt that file using VB.Net
View 2 RepliesI have been having some problems trying to decrypt the string returned back from SagePay.I used their asp.net kit which included the encrypt and decrypt functions using base64 - sending the information to SagePay is not a problem but I am having a number of problems trying to descrypt the string.Here is the function I am using to descypt:
Private Function base64Decode(ByVal strEncoded As String) As String
Dim iRealLength As Integer
Dim strReturn As String
Dim iBy4 As Integer
[code]....
I don't think the web server is trying to encode anything as there are no + symbols within the url string and I have just glanced over the two to compair they are the same.This returns a blank string whereas when I use the sections commented out in the first loop i get a really weired string back and when I use their simpleXor function it just returns complete nonsense.
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]....
I'm using the below function to generate an MD5SH1 hash for SQL backup files.This works well, has progress report etc but is slow if using large files.
Could I generate the MD5 at the same time as SH1 rather than having to process the file twice, doubling the time taken? What about converting an MD5 result to SHA1?
Imports System
Imports System.IO
Imports System.Security.Cryptography
Imports System.Text
[Code]...
I've been trying to work on a personal project, in which the user enters in a text string in the first text box, and when the user clicks the "encrypt" button, the SHA1 hash of the text appears in the next text box. I've googled around for some information on this, and haven't found much for Windows Forms and SHA1, only MD5. I've checked a lot of things on MSDN but to no avail.
View 1 Replieshow to encrypting strings with SHA1, but all of the code I have found does not work or it is to complex for my program. I have found a website that has a encrypting demo program. It worked well so I email the programmer and he gave me this code.
[Code]...
I have some problems with the SHA1 hash value of a string. I'm trying to send a file from a client written in VB.net to a server written in PHP. My problem is that when I pass the same string to VB.net and PHP, the SHA1 value calculated by VB.net is completely different from the value calculated by PHP.
For example, I want to encode a string in Base64 and then calculate the SHA1 Hash of the Base64 string. When the computer executes this task from the vb.net version and from the PHP version I get two different SHA1 values, even if apparently the Base64 encoded string is the same:
VB.net: 2E97A53B09C482A831540B532845BCAC79BFACCF
PHP: 350A2080264E2724D4BCBC521C35264D264A1DAF
I'm surely missing something, could you point me in the right direction and tell me what I'm doing wrong here?
[Code]...
I'm trying to generate an MD5 and SHA1 hash value for a given file with the following:
Imports System
Imports System.IO
Imports System.Security.Cryptography
Imports System.Text
[Code]...
Here is some code that I have that works perfectly:
[Code]...
Is it possible to change the keysize and maybe even choose between MD5 and SHA1 encryption with this code? If not, can someone point me in the right direction to find some that does?
I have 1 string : abc @#ABC.xyz123ZYX
Now I need to encode the string:
The encoding alphabetic characters,
CODE:
With this string, after encoding, the result is: zyx @#ZYX.cba123ABC
About Function Encrypt and Function Decrypt?
I am attempting to find some code to use in VB.NET to decrypt a string that has been encrypted using the Java crypto libary.All of the code I have found so far uses an Initialisation Vector and Key to decrypt but the string has been encrypted using the Key only. (Using an Initialisation Vector is apperently an optional step in Java).Does anyone know of code that I can use (preferably in VB.NET but i could convert C#) to decrypt AES 128 Bit encoded string without an Initialisation Vector?
View 1 RepliesI have a classic ASP page which constructed a querystring for a link to an ASP.NET page. Certain elements in the querystring are somewhat sensitive so I want to encrypt them. I've come across some techniques for doing this in ASP.NET and also in classic ASP but I'm not sure how to do it from classic ASP to ASP.NET. I'm using .NET 3.5.
View 1 Repliesi got encrypt way so how can i decrypt it and the encrypt way is :
View 7 RepliesI'm joining several files and would like to encrypt them with AES. As a test I'm joining the exact same file twice, but I'm never able to properly decrypt the second file.
Steps to reproduce:
Make sure you have a file "C:Original.pdf" or change the filepath.
1) Click Button1 to encrypt the file. This will create an encrypted file named "Encrypted.bin"
2) Click Button2 to decrypt the file. This will create a decrypted file named "Decrypted.pdf"
Both "Original.pdf" and "Decrypted.pdf" are 100% the same.
3) Uncomment the code between the hash character lines.
4) Repeat the first two steps.
"Original.pdf" and "Decrypted.pdf" are now not the same.
vb.net
Private enc As New Encrypt
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
'Encrypt
enc.EncryptDecrypt("C:Original.pdf", "C:Encrypted.bin", True)
[Code] .....
i am trying to decrypt a file that was encrypted with Des. However not all of the file is encrypted just a few lines are. Here is an example of the file im trying to decrypt:
Random text
Encrypted Text
MD5 Hash
Encryption Key(Only there for tests)
Number of encrypted lines
The idea is to read the last three lines into variables and use them to decrypt the text. At the moment i use the number of lines - (the number of encrypted lines + 3) to find where the encrypted text starts. Then i was trying to copy the encrypted text to a temp file so i could run the code bellow on it, however i am getting an encoding error apparently i need to be using base64 or something. So my question is can anybody explain to me or show me how i can pull the encrypted text out of the file so that i can use the code bellow on it.
Dim DES As New DESCryptoServiceProvider()
'A 64-bit key and an IV are required for this provider.
'Set the secret key for the DES algorithm.
[Code].....
I would like to decrypt a files that sis coming to me as pgp, is there anyway of doing this. without the pgp command or any other third party dll. or I rememeber A long time ago there was a .dll called NSDpgp3.dll but it only works with vb6 ( sdpgp3 was free)
View 2 RepliesTHIS IS THE SAMPLE OF ENCRYPTED DATA PLEASE HELP ME HOW TO DECRYPT THIS KIND OF ENCRYPTION
View 2 RepliesI 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]
View 14 RepliesI ended up getting this properly working, as far as encrypting a file goes:How to encrypt and decrypt a file by using Visual Basic .NET or Visual Basic 2005 However, the catch is I have to change the name of the output file. What I was hoping to do is overwrite the original with the encrypted file, but when I tried that on a large file, it ended up only getting about 8 bytes of it.
Does anybody have any suggestions or recommendations? The overall idea is that I want to keep a file encrypted until it needs to be unencrypted for use by a program, but I'm not sure if there are better tools out there or if there's a better way of accomplishing this.
Question 2: I would really, really like to encrypt an entire folder, which I'm guessing would be faster than file by file, but when I try I keep getting access denied errors, even with DOS Cipher. Is there a way to do this with a key?
there is anyone know how to encrypt and decrypt app config in vb.net??i want encrypt connection string and appsettings .
View 4 RepliesHow to encrypt and decrypt database..
View 4 Replies