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Questions tagged [encryption-symmetric]

A type of encryption where the same key is used to encrypt and decrypt the message.

Symmetric encryption is the oldest and best-known technique. A secret key, which can be a number, a word, or just a string of random letters, is applied to the text of a message to change the content in a particular way. This might be as simple as shifting each letter by a number of places in the alphabet (known as the Caesar Cipher), or as complicated as the Advanced Encryption Standard, which is used in some modern cryptography. Anyone who knows the key can either encrypt or decrypt a message.

Note that symmetric encryption does not require that the encryption and decryption key be identical, but rather that both keys derive from the same knowledge. For example, a letter-shifting cipher might require that "A" be enciphered as "G" - the opposite operation would be needed to decrypt.

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Symmetric decrypting returns a NULL value

I have two databases . I copied all the data from one table and inserted into another database table . I have created symmetric key on second database but when i try to run the query as follow OPEN SYMMETRIC KEY SecureSymmetricKey DECRYPTION BY…
pardeep dhingra
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Cipher.getInstance() is failing with java.security.NoSuchAlgorithmException: Cannot find any provider supporting AES/ECB/ZeroBytePadding

I have an Android app that encrypts data using AES with ECB and ZeroBytePadding. Everything works fine in that environment: encrypted data gets decrypted in Android without a problem, as follows: public static String encrypt(byte[] raw, byte[]…
FractalBob
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Java multi-level aes de/encrypting fails

I have been tasked with decrypting a file in Java that has been encrypted using the following criteria: Encrypting: ` byte[] masterKey; if (Base64.decode(config.getProperty("encrMasterKey")) != null) { …
hellfiend
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Padding is invalid and cannot be removed aes

I have searched solutions on this website but none solved my problem. Sometimes I recieve "padding is invalid and cannot be removed" exception. I don't know what to do. When I tried some solutions, there was empty decrypted text or it didn't…
Robert
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In-built key Generation Algorithm using SHA256

I am working on an application in c# .Net where data needs to be encrypted and Since data privacy is my ultimate motive , I am doing it using AES Encryption and I use PasswordDervieBytes for determining the Secret Key. Now Since it uses SHA1 which…
user2107833
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SQL Server symmetric key is lost, how to decrypt the data?

We are in a situation where symmetric key and certificates are deleted, Is there any way can we decrypt the data? We tried decrypting the data with same script which was used for creating the master key , certificate and symmetric keys.…
Vivek
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How can I decrypt data stored in XML using the XML Encryption Syntax and Processing spec?

How could I use C# to decrypt this XML file while I know the password?
Ahmed Darwish
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Android RC2 Encryption

I'm working on making an Android client for a fairly old webservice. The webservice requires that I encrypt some of the data I send to it in RC2 style. I'm having trouble getting anything (Cipher, KeyFactory, KeyGenerator, etc.) to even have an…
BlargleMonster
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Is there any difference between implementation of Triple DES in C# and Java? Java gives error wrong IV size

In our application we are using Triple DES to encrypt and decrypt the data. We have the enc/dec code in C# which uses 24 byte key and 12 byte IV which works fine. Now we want to implement same code in java but when I use 12 byte IV, I get an error…
Tejas
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Is there a significant risk to encrypt the secret with itself as key (with salt)?

I'd like to store user passwords encrypted in a database. I need to use a bidirectional, symetrical encryption, eg. AES (using a hash is not an option in this special case). Part 1 Is there a significant increased risk in using the string that I…
Zeemee
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Symmetric encryption using Dukpt

I am new to this forum. Recently I am tasked to decrypt a file that is encrypted using AES encryption( which require a secret key for encryption and decryption as well). File use to encrypt in every 5 minute using a DUKPT . I am working on c# .By…
Satish2230
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BadPaddingException: invalid ciphertext

I would like some help as this is my first time in coding cryptography code. The encryption code appears to be working correctly, but the decryption throws an error. The error I get is: de.flexiprovider.api.exceptions.BadPaddingException: invalid…
Mike
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perl encryption script IDEA

Hi everyone im making a perl script to encrypt and decrypt text, i just have started i have this: #!/usr/bin/perl use Crypt::IDEA; my $key = pack("H32", "0123456789ABCDEF0123456789ABCDEF"); my $cipher = new IDEA $key; my $palabra= "plaintex"; my…
fpilee
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Shared-Key Signature

I know that most uses of cryptographic signatures are with public/private keys, but I need to sign information using a pre-shared key. I know I can just encrypt the data, but I prefer signing it.. Is it possible in C#?
Roy Reznik
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encrypting a Document using vigenere cipher

I'm interested in learning about different encryption techniques and have started to implement a vigenere cipher in c#. I can implement a windows forms which allows me to encrypt and decrypt a string similar the following…
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