Re: [TLS] Headerless records (was: padding)

2015-08-25 Thread Martin Thomson
On 24 August 2015 at 21:04, Dave Garrett wrote: > uint16 length = TLSPlaintext.length; You can't recover the plaintext without knowing how long it is. This part at a minimum needs to be in the clear. At which point you need it to be based on TLSCiphertext.length ___

Re: [TLS] Privacy considerations - identity hiding from eavesdropping in (D)TLS

2015-08-25 Thread Pascal Urien
Hi a working solution fot TLS 1.0,1.1, 1.2, DTLS 1.0, 1.2 is to encrypt the client certificat with an extra key computed from the master secret see https://tools.ietf.org/html/draft-urien-badra-eap-tls-identity-protection-01 Rgs Pascal 2015-08-24 22:56 UTC+02:00, Viktor S. Wold Eide : > Hi, >

Re: [TLS] padding

2015-08-25 Thread Yoav Nir
> On Aug 25, 2015, at 2:22 AM, Tom Ritter wrote: > > On 22 August 2015 at 19:28, Dave Garrett wrote: >> Toggling solves the undesired bandwidth use concern stated by Tom by making >> it fully optional on both sides. The even simpler route of just having to >> check if there's bytes in the enc

Re: [TLS] Headerless records (was: padding)

2015-08-25 Thread Kyle Rose
>> uint16 length = TLSPlaintext.length; > > You can't recover the plaintext without knowing how long it is. This > part at a minimum needs to be in the clear. At which point you need > it to be based on TLSCiphertext.length Is that really true? You could decrypt the first block/few bytes

Re: [TLS] Headerless records (was: padding)

2015-08-25 Thread Viktor Dukhovni
On Tue, Aug 25, 2015 at 10:26:24AM -0400, Kyle Rose wrote: > (I am not claiming anything about the purity of this approach, only > that it is technically feasible.) SSH now has ciphersuites where the payload length is encrypted, IIRC via a key that is different from the payload key. --

Re: [TLS] Headerless records (was: padding)

2015-08-25 Thread Martin Thomson
On Aug 25, 2015 7:26 AM, "Kyle Rose" wrote: > > >> uint16 length = TLSPlaintext.length; > > > > You can't recover the plaintext without knowing how long it is. This > > part at a minimum needs to be in the clear. At which point you need > > it to be based on TLSCiphertext.length > > Is t

Re: [TLS] Headerless records (was: padding)

2015-08-25 Thread Martin Thomson
On Aug 25, 2015 7:42 AM, "Viktor Dukhovni" wrote: > SSH now has ciphersuites where the payload length is encrypted, > IIRC via a key that is different from the payload key. Yeah, I'm not that enthusiastic about that feature, but if you want more complexity, it is possible. The authentication prope