On 16 March 2013 18:00, azhar jodatti <azhar...@gmail.com> wrote: > > > Thompson, > > Really thanks for the reply. appreciate your time. > > Yes it was JCE and not JCF. it was typo :) > > I am working on application which has android and iPhone client. Both the > client talk to my server which is written in JAVA. I am using JCE > implementation of DH algorithm and X509EncodedkeySpec for generating > public and private key. code below > > X509EncodedKeySpec x509Spec = new > X509EncodedKeySpec(this.clientPublicKey); > PublicKey pk = kf.generatePublic(x509Spec); > > for the android client I am using same JCE implementation of DH algorithm > and it works fine with my server. > > for iPhone client I wrote a C programme which makes use of openSSl > implementation of DH algorithm. The problem I am facing is when I generate > DH params (prime,generator,pulickey) at client and pass them to server to > calculate server's public and secret key, my server (JAVA) throws > invalidKeySpecification exception. below are steps. > > Client in C > 1. I am generating DH parameters (prime,generator) > //client is DH *client. > //also tried with 1024 bits and DH_GENERATOR_5 > DH_generate_parameters_ex(client,512,DH_GENERATOR_2,NULL); > 2. then generating DH public and private key > DH_generate_key(client) > when I pass these (prime,generator,publickey ) generated keys to server > which is written in JAVA , It won't work. server (JAVA) throws > invalidKeySpecification exception. >
Is there any particular reason why you are using the low level interface for this. Typically using the high level EVP interface is preferred. See: http://www.openssl.org/docs/crypto/EVP_PKEY_derive.html To generate parameters: /* Create the context for generating the parameters */ if(!(pctx = EVP_PKEY_CTX_new_id(type, NULL))) goto err; if(!EVP_PKEY_paramgen_init(pctx)) goto err; /* Set a prime length of 2048 */ if(!EVP_PKEY_CTX_set_dh_paramgen_prime_len(pctx, 2048)) goto err; /* Generate parameters */ if (!EVP_PKEY_paramgen(pctx, ¶ms)) goto err; To generate keys: if(!(kctx = EVP_PKEY_CTX_new(params, NULL))) goto err; if(!EVP_PKEY_keygen_init(kctx)) goto err; /* Generate the key */ if (!EVP_PKEY_keygen(kctx, &key)) goto err; To get the parameters afterwards you can use: DH *EVP_PKEY_get1_DH(EVP_PKEY *pkey); So, how are you transmitting the parameters and public keys between the Java and C? Matt
