My mistake. I was reading the calls backwards. The use of c_str() there is fine. Ignore my previous comment.
From: openssl-users [mailto:openssl-users-boun...@openssl.org] On Behalf Of Jason Qian Sent: Friday, March 18, 2016 2:34 PM To: openssl-users@openssl.org Subject: Re: [openssl-users] help on des_cblock Thanks, Jason On Fri, Mar 18, 2016 at 4:23 PM, Scott Neugroschl <scot...@xypro.com<mailto:scot...@xypro.com>> wrote: I suspect the use of std::string and c_str(). Use a std::vector<char> instead. From: openssl-users [mailto:openssl-users-boun...@openssl.org<mailto:openssl-users-boun...@openssl.org>] On Behalf Of Jason Qian Sent: Friday, March 18, 2016 1:19 PM To: openssl-users@openssl.org<mailto:openssl-users@openssl.org> Subject: [openssl-users] help on des_cblock I am new on openSSl and run into a issue need some help. In our application, the client and server perform a Diffie Hellman Key exchange and then encrypt the data The client is written in C++(using openSSL), and server is in java. Most of time, it is running correctly, but occasionally the server(java) throw a "Given final block not properly padded" exception. I added more log on the both side. When the exception happen, the keys are offset by one(for the working case, they are the same) Server -- java get from getEncoded() DES Key size (8) (1,-83,-113,-74,-77,109,84,88) Client -- openSSL get from des_cblock struct DES Key size (8) (-83,-113,-74,-77,109,84,88,8) Thanks Jason Here is the C++ code void DiffieHellmanCipher::init(const std::string &Y){ if (Y.length() == 0) { return; } if (m_DH == NULL) { return; } // convert the Y to BIGNUM BIGNUM *bnY = NULL; // Memory for bnY is allocated in BN_dec2bn call. if (!BN_dec2bn(&bnY, Y.c_str())) { if (bnY) BN_free(bnY); printf("Could not convert Diffie-Hellman Y value to BIGNUM"); } // compute the secret key int dhSize = DH_size(m_DH); unsigned char *secretKey = (unsigned char*) new char[dhSize + 1]; int secretKeyLen = DH_compute_key(secretKey, bnY, m_DH); BN_free(bnY); if (secretKeyLen < 8) { delete [] secretKey; printf("Error computing secret key: key length is too short"); } // convert from raw form to odd parity DES key des_cblock desKey; memcpy(desKey, secretKey, 8); delete [] secretKey; DES_set_odd_parity(&desKey); //just print out des_cblock secretKeyString="("; char ch[10]="\0"; for(int i=0;i<8;i++){ sprintf(ch,"%d",(char)desKey[i]); secretKeyString+=ch; if(i != 7){ secretKeyString+=","; } } secretKeyString+=")"; int skRet; if ((skRet = DES_set_key(&desKey, &m_DESKey)) != 0) { delete [] secretKey; printf("Error computing secret key: generated key is weak"); } m_bInited = true; } -- openssl-users mailing list To unsubscribe: https://mta.openssl.org/mailman/listinfo/openssl-users
-- openssl-users mailing list To unsubscribe: https://mta.openssl.org/mailman/listinfo/openssl-users