[cryptography] Forum Topics

I need some help to make AES work with UDP. I keep getting this error. Exception in thread "main" javax.crypto.IllegalBlockSizeException: Input length must be multiple of 16 when decrypting with padded cipher at com.sun.crypto.provider.CipherCore.doFinal(CipherCore.java:750) at com.sun.crypto.provider.CipherCore.doFinal(CipherCore.java:676) at com.sun.crypto.provider.AESCipher.engineDoFinal(AESCipher.java:313) at javax.crypto.Cipher.doFinal(Cipher.java:2087) at AES.decrypt(AES.java:31) at EchoServer.main(EchoServer.java:26) It seems that upon receiving the …

"Active cracking" means indirectly changing a plaintext message so that it becomes a totally different, plaintext message that says something totally different but still makes sense, by creating a brand new encryption key that is applied to the ciphertext itself and changes the ciphertext rather than the original plaintext. I …

Hi I have a problem with RSA encryption/decription of txt files, I have one method to create a pair of RSA keys and save them into a file, then i made two methods, one for encryt and one for decrypt, encrypt method works fine, but when I want to decrypt …

hey i am trying to implement the diffie hellman key exchange algorithm in matlab. my problem is this: the program works just fine for numbers upto 5 digits, but after that it just sort of stops working. thing is i need to deal (multiply,exponentiation,modular arith etc.) with really big numbers …

the rc6 paper say this [CODE]Key schedule for RC6-w/r/b Input: User-supplied b byte key preloaded into the c-word array L[0; ..., c - 1] Number r of rounds Output: w-bit round keys S[0; ..., 2r + 3] Procedure: S[0] = Pw for i = 1 to 2r + 3 do …