encryption

How to get compatibility between C# and SQL2k8 AES Encryption?

I have an AES encryption being made on two columns: one of these columns is stored at a SQL Server 2000 database; the other is stored at a SQL Server 2008 database. As the first column's database (2000) doesn't have native functionality for encryption / decryption, we've decided to do the cryptography logic at application level, with .N...

Bad crypto error in .NET 4.0

Today I moved my web application to .net 4.0 and Forms Auth just stopped working. After several hours of digging into my SqlMembershipProvider (simplified version of built-in SqlMembershipProvider), I found that HMACSHA256 hash is not consistent. This is the encryption method: internal string EncodePassword(string pass, int passwordForm...

CryptoExcercise Encryption/Decryption Problem

I am using apples "cryptoexcercise" (Security.Framework) in my application to encrypt and decrypt a data of numeric value. When I give the input 950,128 the values got encrypted, but it is not getting decrypted and exists with the encrypted value only. This happens only with the mentioned numeric values. Could you please check this iss...

SSL encrpytion, SHA1 and SHA2

Hello, I am trying to implement SHA2 encryption instead SHA1. For this, I know that bit number between these two hash algorithms are different and it confuses me. How can this be achieved and at what parts do I need to make required changes. I can use any open source library from Java, Python and any other major programming language....

Encrypting Files with AES, Encrypting Key with RSA - Am I on the right track?

Overview: I'm trying to design an application that will encrypt files to safely send through Snail Mail (LARGE sets of data). I'm planning on using AES/RijndaelManaged encryption from .Net to encrypt the files initially, using a randomly generated key using RNGCryptoServiceProvider. I'm then encrypting this random AES key with a RSA Pu...

How to make html file encrypted?

Hey Guys, I want to know, how to make my html file code to encrypted? So that if normal user see the code, then they don't understand the code? ...

How to encrypt HTML source code output using PHP

I want to deter novice users from seeing the source code. I have a php code that generates a html page. edit1: I came across a simple tool which encrypted html code into %C%D%F but which worked with the browser just fine. ...

Is it viable and necessary to encrypt bytes?

We have a requirement from customer that if someone gets access to the database, all data that includes personal information should be encrypted, so that when they do select calls, they shouldn't be able to see anything in clear text. Now this isn't any problem for Strings, but what about bytearrays? (that can potentially be quite huge (...

iPhone Encryption Standard - Will this implementation bye-pass apple check?

Hi All, I found this implementation, and i am not sure whether we can use this implementation and apple will bye-pass extra check, this is a base-64 implementation. The source code link is http://blog.objectgraph.com/wp-content/uploads/2010/04/CryptTest.zip The web page link is : http://blog.objectgraph.com/index.php/2010/04/20/encry...

iphone encryption not working

I have this encryption/decryption implemented and executes with no error, but i am unable to decrypt the data and im not sure whether the data is encrypted, kindly help. - (NSData *)AES256EncryptWithKey:(NSString *)key { char keyPtr[kCCKeySizeAES256+1]; bzero(keyPtr, sizeof(keyPtr)); [key getCString:keyPtr maxLength:sizeof(keyPtr) e...

What is the difference between DSA and RSA?

It appears they are both encryption algorithms that require public and private keys. Why would I pick one versus the other to provide encryption in my client server application? ...

How to encrypt a file using a Public Key in C#?

I have a 2048 bits public key (asymmetric, RSA) of which I know the Modulus and Exponent and need to encrypt a string. Ideally, I want to encrypt a small string in c# and later on decrypt it with python. ...

Secure password transmission over unencrypted tcp/ip

I'm in the designing stages of a custom tcp/ip protocol for mobile client-server communication. When not required (data is not sensitive), I'd like to avoid using SSL for overhead reasons (both in handshake latency and conserving cycles). My question is, what is the best practices way of transmitting authentication information over an ...

Is there a public / private key encryption scheme that will not change a message's length?

Is there a public / private key encryption scheme that will not change a message's length? I would like to encrypt a message one packet at a time, but if the packet grows, it would no longer just be one packet long. ...

From an established ssh connection, what is a good way to encrypt messages on the side?

If I have a connection between a client and a server using ssh. What is a good way to encrypt data sent outside the ssh connection for sending large amounts of data quickly and securely? I can use the ssh connection to set up the terms of the communication, sharing keys etc, but then will do the communication on the side. ...

How to build this encryption system that allows multiple users/objects.

Hello! I am trying to figure out how to create an optimal solution for my project. I made this simple picture in Photoshop to try to illustrate the problem and how i want it (if possible). Illustrative image Ill also try to explain it based on the picture. First off we have a couple of objects to the left, these objects all get encryp...

(Secure) alternative to TLS / SSLv3 ?

Toying with an idea for a F2F networked application I've just been reading up on secure communication. I quickly settled with the idea of using TLS / SSL as the basis for any communication since it employs Public Key encryption at the protocol level and thus is perfect for my needs. However I was surprised to read (on wikipedia) that the...

What is an s2k algorithm?

What is the definition of an s2k algorithm? For example, "PBKDF2(SHA-1)" is an s2k algorithm. Here is some Botan code that refers to s2k: AutoSeeded_RNG rng; std::auto_ptr<S2K> s2k(get_s2k("PBKDF2(SHA-1)")); s2k->set_iterations(8192); s2k->new_random_salt(rng, 8); SymmetricKey bc_key = s2k->derive_key(key_len, "BLK" + pass...

When encrypting data that is not an even multiple of the block size do I have to send a complete last block?

If I am using a block cipher such as AES which has a block size of 128 bits, what do I do if my data is not an even multiple of 128 bits? I am working with packets of data and do not want to change the size of my packet when encrypting it, yet my data is not an even multiple of 128? Does the AES block cipher allow handling of a final b...

Does having an unencrypted sha-224 checksum create a vulnerability?

If I have a packet of data that is encrypted yet also includes a sha-224 checksum that is not encrypted, am I creating a security vulnerability? Or perhaps the checksum should be produced after encryption? ...