Re: [openssl-users] Security of DH in TLS

2017-07-26 Thread Paul Yang
No idea on OpenVPN, I guess you could ask them directly : ) > On 26 Jul 2017, at 18:38, SaAtomic wrote: > > > Thank you for the elaboration and the link. > One more follow-up question :) > > With OpenVPN, when I configure a TLS cipher suite like >

Re: [openssl-users] Security of DH in TLS

2017-07-26 Thread SaAtomic
Thank you for the elaboration and the link. One more follow-up question :) With OpenVPN, when I configure a TLS cipher suite like `TLS-ECDHE-ECDSA-WITH-AES-128-GCM-SHA256`, I never manually created an ECC private key. You mentioned that this is required for such cipher suites. Does in this

Re: [openssl-users] Security of DH in TLS

2017-07-26 Thread Paul Yang
> On 26 Jul 2017, at 16:21, SaAtomic wrote: > > The subject is much clearer to me now, thank you. > > The EC key you mentioned is not created manually, correct? > This key is a result of ECC, which is done by OpenSSL. > > So if I set up a server offering TLS connections

Re: [openssl-users] Security of DH in TLS

2017-07-26 Thread SaAtomic
The subject is much clearer to me now, thank you. The EC key you mentioned is not created manually, correct? This key is a result of ECC, which is done by OpenSSL. So if I set up a server offering TLS connections and only offer ECDH/ECDHE, no additional data has to be generated manually,

Re: [openssl-users] Security of DH in TLS

2017-07-26 Thread Paul Yang
> On 26 Jul 2017, at 15:56, SaAtomic wrote: > > Thanks for the reply. > I'm still not sure I understand this correctly. > > So the length of modulus is the essential part, determining the security of > the DH, right? Mostly. > With ECC, this is defined by the used

Re: [openssl-users] Security of DH in TLS

2017-07-26 Thread SaAtomic
Thanks for the reply. I'm still not sure I understand this correctly. So the length of modulus is the essential part, determining the security of the DH, right? With ECC, this is defined by the used curves. Without ECC, this is determined by the DH parameters (from the .pem file I mentioned).

Re: [openssl-users] Security of DH in TLS

2017-07-26 Thread Paul Yang
The ‘key size’ concept is usually referred to the length of modulus. (In public key crypto area) For DH and ECDH, it (the size) ’s generated and defined in the ‘parameters’, as you pasted. Parameters are not exactly the final ‘keys’, they are the ‘materials’ to produce keys (both private ones