diffie-hellman

This is the code that I'm using to generate a DH keypair: KeyPairGenerator keyGen = KeyPairGenerator.getInstance("DH"); keyGen.initialize(1024, new SecureRandom()); KeyPair ackp = keyGen.generateKeyPair(); (without the needed try/catch, of course). I've done some tests running such code iteratively and varying the key size (in particular ramping up from 128 with a 128 step up to 1024. 1024 would be the desired size. First of all, running each size generation 10 times to have some minimal std deviation on the results gives HIGH fluctuation of results, on average, anyway, the time needed for

在git clone 项目的时候， 竟然报错了：no matching key exchange method found. Their offer: diffie-hellman-group1-sha1 那么，想要解决此问题， 则需要在用户目录下的 .ssh文件夹下新建一个 config 文件，添加： 　　 Host * 　　KexAlgorithms +diffie -hellman -group1 -sha1 　　 然后，再重新执行 git clone : 至此， git clone 成功， 问题解决！ 原文：https://www.cnblogs.com/suwyer/p/9256102.html

I'm using OpenSSL's c library to generate an elliptic curve Diffie-Hellman (ECDH) key pair, following the first code sample here . It glosses over the actual exchange of public keys with this line: peerkey = get_peerkey(pkey); The pkey variable and the return value are both of type EVP * . pkey contains the public key, private key, and params generated earlier, and the return value only contains the peer's public key. So this raises three questions: How would get_peerkey() actually extract just the public key from pkey for sending to the peer? How would the code extract the private key and

I have the following code that converts a DH secret key to AES secret key. This used to work until Oracle JRE 8u161 when they started restricting creation of DH keys < 1024 in java.security file. Now, I will get NoSuchAlgorithmException: Unsupported secret key algorithm AES at the last line. PrivateKey privKey = null; PublicKey pubKey = null; PublicKey agreement = null; KeyAgreement keyAgreement = KeyAgreement.getInstance("DH"); keyAgreement.init(privKey); keyAgreement.doPhase(pubKey, false); keyAgreement.doPhase(agreement, true); SecretKey key = keyAgreement.generateSecret("AES"); I tried

what are the differences between the three key exchange algortihms namely Anonymous DH, Ephermal DH and fixed DH? From Cisco's docs : Fixed Diffie-Hellman: This a Diffie-Hellman key exchange in which the server's certificate contains the Diffie-Hellman public parameters signed by the certificate authority (CA). That is, the public-key certificate contains the Diffie-Hellman public-key parameters. The client provides its Diffie-Hellman public key parameters either in a certificate, if client authentication is required, or in a key exchange message. This method results in a fixed secret key

I am trying to export the keys from a new instance of a ECDiffieHellmanCng object so I can create an instance of it later with the same keys. But I am getting an error when trying to export it. //Create new ECDiffieHellmanCng which automatically creates new keys var ecdh = new ECDiffieHellmanCng(); //Export the keys var privateKey = ecdh.Key.Export(CngKeyBlobFormat.EccPrivateBlob); I am getting a CryptographicException when I call the Export method with the message " The requested operation is not supported. " After putting some breakpoints in the code it looks like it is throwing the