[cryptography] Forum Topics

Hi to all the old familiar faces, have not been here for a while... I have read up on tons of samples and answers (and even more on how cryptography works) but none answers my scenario. I am creating a new user from desktop app in VB.Net. User need to …

Hi All, am trying to use build a secure login page. I have written necessary functions and the registrations works fine (with secure hash + salt passwords created) but the verification never goes through. Can someone point me in the right direction? Imports System.Data Imports System.Data.SqlClient Imports System.Security.Cryptography Imports System.Web.Security …

Don't you just get sick of hash algorithms constantly been brute forced or even cracked. Well here is an algorithm I have created in my spare time to help out the little guy who just wants a secure hash. This hashing algorithm uses many different techniques including ones used in …

Hello, So I basically loaded to 2 keys and I want to verify them after I've signed something with one of them, but I a having difficulties. I am getting verified: false at the end without any error. Can someone please point out the flaw? package fliesigning; import static fliesigning.FlieSigning.verifySig; …

Hello everybody. I meeting you new. I want make the some project about stegenografi in C#. Actually i want preserve some message in picture with the kriptografi like a RSA etc. How can do u help me for the find the document

I have to perform cryptanalysis of vigenere cipher using C...i was able to get a key for a given cipher text., and now i want to get the plain text as well. Is it possible to get the encoded message from the user and generate the cipher text using a …

I am trying to make a simple cryptography program using a simple subsitution method. If any one could help that would be nice. I need to be able to encode it as well as decode it. but im just a little confused on how to go about doing that. here …

hello, Can anyone please tell me the most efficient know till date so as to find the prime numbers up to 10^8 or higher. I am using sieve and using odd number optimization with it also. but it is not too much effiecent which i want. Can you please any …

i Wana start a project on this topic. what is the scope of this topic as i want to do MS in future. Is there any coding related work in this ? I have just started this project 5 days before. thanks.

Guys im trying to generate a SA-1 code for the password and i have used this code Dim en As New System.Security.Cryptography.SHA1CryptoServiceProvider Dim bt() As Byte = System.Text.Encoding.ASCII.GetBytes(TextBox2.Text) Dim chs 'hash string that will be generated' bt = en.ComputeHash(bt) For Each b As Byte In bt chs = chs + …

For a given digitally signed file I need to extract the 1024 bit(RSA) public sign key that is shown in the attachment. Can someone tell me how to do that through python. Is there a specific python module that can extract the digital signature details? If that is not possible …

i need help using MAC from javax.crypto package. i am able to generate MAC codes using keys but i am getting different mac's for the same message using the same key.can anyone plz give a small foolproof code to generate mac from say a small message like "hello world" so …

so im very new to programming, its a miracle and a half i managed to get java reinstalled after a year and a half of not using it im taking a cryptography class, the teacher wants to show us the code behind some algorithms, like des and 3des, and in …

Ok, i made a code to Encrypt a file (any file), but i have a problem to do the Decrypter and the code to the Decrypter (doesn't work) [CODE]if (RestoreFile.ShowDialog() == DialogResult.OK) { FileStream fsFileIn = File.OpenRead(o.FileName); FileStream fsKeyFile = File.OpenRead(o.FileName); FileStream fsFileOut = File.Create(RestoreFile.FileName); TripleDESCryptoServiceProvider cryptAlgorithm = new TripleDESCryptoServiceProvider(); …

In Dorothy Sayers' novel "Have His Carcass", Lord Peter Wimsey describes a cryptography technique that is simple for encoding and decoding, yet relatively hard to crack. Your job is to implement this technique. Here's how it works, in Sayers' (edited) words: You choose a key-word of six letters or more, …

im a first year engg student. i need 2 make a report on cryptography and i need the source code in C for caeser cipher. as it so happens im not very good at c programming... please help can u tell me wats wrong wid this program? #include <stdio.h> void …

[CODE]def egcd(a,b): u, u1 = 1, 0 v, v1 = 0, 1 while b: q = a // b u, u1 = u1, u - q * u1 v, v1 = v1, v - q * v1 a, b = b, a - q * b return u, v, a …

I am hoping I can get some help from you guys, I am taking a computer security course and we need to write a Caesar Cipher program, where you can input the text and offset and get the the encrypted results back. I have run into a problem with it …

Hi, for any of you who have done some java programming in cryptography I need your help. I'm trying to right and blinding and unblinding procedure, however at the final stage I should get a true, but I'm getting a false. If you know what's wrong, can you point it …

Hi everyone, I'm looking to write a server/client negotiation which involves both the server and client choosing a random number, sending it to one another, then generating a string using the two random numbers and some other previously found information. Using the hash of this string the client and server …

For those who understand El Gamal signature scheme . U may have known the verification process of the signature : y^a *a^b (mod p ) = g^M (mod p) We have to compute both side of the equation. If they are equal, the signature is verified. but i have issue …

can u guys gimme sum ideas on wat project can be done?i am required to do a program and a thesis about it... My interests are in IT Security, Computer Security, Cryptography and creating normal programs. I am really unsure on wat prjoect should i do? wat program should i …

Hi everyone. I'm new here and would like some help with some Python code. I'm trying to use modulus to shift decode an input line (regular sentence or word like "Bill") but I keep going over the regular alphabet in ascii and the "B" becomes an "=" How do I …

Reposting from [url]http://www.mentalis.org/forum/thread.qpx/971[/url] because I need an answer. I hope you guys can help me out. The component in question is Org.Mentalis.SecurityServices.dll. Hey all. I'm having troubles. CryptographicException: Couldn't acquire crypto service provider context. StackTrace: at Org.Mentalis.SecurityServices.Cryptography.CryptoHandle.CreateInternalHandle(IntPtr handle, String container) at ORG.Mentalis.SecurityServices.Cryptography.CryptoHandle.get_Handle() at Org.Mentalis.SecurityServices.Cryptography.RC4CryptoServiceProvider.ctor() at I had to copy that …

This code takes a string a cyphers it by shifting it's position in the alphabet. I've gotten it so it can pretty much take paragraphs. It's quite neat to play with. For example the above when shifted to 5, would be: Ymnx htij yfpjx f xywnsl f hDumjwx ny gD …

Hello, sorry for my english. I have a little problem. I want to verify the integrity of my certificat. I make this code: [CODE] using System.Security.Cryptography; using System.Runtime.InteropServices; using System.Security.Cryptography.X509Certificates; SHA1Managed sha1 = new SHA1Managed(); RSACryptoServiceProvider csp = null; AsymmetricAlgorithm rsaAlgo = certificatEnCours.PublicKey.Key; byte[] data = null; byte[] hash = …

I have some questions about using Cavium CSP, which need your kindness help. According to the explain in MSDN, the function 'CryptDestroyKey' of CRYPTAPI will not only destory the key handle, but also free the memory that the key occupied. But using Cavium CSP, the function does not free the …

I am working on the project of cryptography and i have entered text in textbox and convert into hexadecimal numbers or binary numbers and store into the one array using the shift function. Shift each binary digit from their place and store it into array and vice-versa. how can i …

new to forums ... dunno how to use them learnin them :$ ... doin my btech second year ... sort of got a project to do in cryptography ... digital signatures and need help ...

i need to use large integers of the size 1024 to 2048 in a cryptography project using C... are there any header files available which will make my work easier if not ... how do i hanlde these integers using structures ??? By handling i mean multiplication , exponentation , …

ok, not a computer geek...so I figured one of you could help me figure this out. I've read about Francis Bacon's Bilateral Ciphers...still can't make heads or tails out of them. I need to understand them and more specifically, a Bacon cipher with regular letters and Roman numerals involved. Is …