Re: Where are others SHA256 cipher suits in Firefox 27?

2014-03-23 Thread gegard4321
Another reason to enable DHE_RSA_AES_*_GCM: Mozilla's new account system only
supports RSA and DHE_RSA ciphers:
https://www.ssllabs.com/ssltest/analyze.html?d=accounts.firefox.com
Same goes for mozilla.org and bugzilla.



--
View this message in context: 
http://mozilla.6506.n7.nabble.com/Where-are-others-SHA256-cipher-suits-in-Firefox-27-tp306678p311535.html
Sent from the Mozilla - Cryptography mailing list archive at Nabble.com.
-- 
dev-tech-crypto mailing list
dev-tech-crypto@lists.mozilla.org
https://lists.mozilla.org/listinfo/dev-tech-crypto


Re: Where are others SHA256 cipher suits in Firefox 27?

2014-03-23 Thread Julien Vehent

On 2014-03-23 11:43, gegard4321 wrote:
Another reason to enable DHE_RSA_AES_*_GCM: Mozilla's new account 
system only

supports RSA and DHE_RSA ciphers:
https://www.ssllabs.com/ssltest/analyze.html?d=accounts.firefox.com
Same goes for mozilla.org and bugzilla.


On the server side, we are working to support better TLS. See this 
Tracker bug: https://bugzilla.mozilla.org/show_bug.cgi?id=901393


Depending on the technology used, not all ciphers are available on all 
sites. But I can already tell you that accounts.firefox.com will support 
ECDHE and AES-GCM.


- Julien
--
dev-tech-crypto mailing list
dev-tech-crypto@lists.mozilla.org
https://lists.mozilla.org/listinfo/dev-tech-crypto


Re: Where are others SHA256 cipher suits in Firefox 27?

2014-03-23 Thread Kurt Roeckx
On Sun, Mar 23, 2014 at 08:43:35AM -0700, gegard4321 wrote:
 Another reason to enable DHE_RSA_AES_*_GCM: Mozilla's new account system only
 supports RSA and DHE_RSA ciphers:
 https://www.ssllabs.com/ssltest/analyze.html?d=accounts.firefox.com
 Same goes for mozilla.org and bugzilla.

Firefox selects TLS_DHE_RSA_WITH_AES_128_CBC_SHA, while chrome
selects TLS_DHE_RSA_WITH_AES_128_GCM_SHA256.  And I would really
prefer the GCM version over the CBC version.

Please add support for TLS_DHE_RSA_WITH_AES_*_GCM_SHA*, which
currently probably means TLS_DHE_RSA_WITH_AES_128_GCM_SHA256.


Kurt

-- 
dev-tech-crypto mailing list
dev-tech-crypto@lists.mozilla.org
https://lists.mozilla.org/listinfo/dev-tech-crypto


Re: Where are others SHA256 cipher suits in Firefox 27?

2014-03-23 Thread gegard4321
On the server side, we are working to support better TLS.

Thanks for the information.
Please also have a look at AMO, it doesn't even support TLS 1.2 and Forward
Secrecy:
https://www.ssllabs.com/ssltest/analyze.html?d=addons.mozilla.org



--
View this message in context: 
http://mozilla.6506.n7.nabble.com/Where-are-others-SHA256-cipher-suits-in-Firefox-27-tp306678p311571.html
Sent from the Mozilla - Cryptography mailing list archive at Nabble.com.
-- 
dev-tech-crypto mailing list
dev-tech-crypto@lists.mozilla.org
https://lists.mozilla.org/listinfo/dev-tech-crypto


Re: Where are others SHA256 cipher suits in Firefox 27?

2014-02-09 Thread gegard4321
Lucky13 is a timing attack on MAC-then-Encrypt, which CBC uses.
This attack can be fixed, but it's harder to get this right than
it should be.
Maybe you're refering to the BEAST attack instead of Lucky 13,
which TLS 1.1 fixed and can be worked around in older versions
by splitting?
Anyway, I see no need for adding support for ciphers that do not
support forward secrecy.
Yes, because CBC is vulnerable to Lucky13, using GCM will not be vulnerable,
thus GCM support is important.
So if some sites support GCM but not Forward Secrecy, making
TLS_RSA_WITH_AES_128_GCM_SHA256 available in Firefox, they will at least be
safe from Lucky13.
But on the other hand I agree with you that supporting new ciphers without
Forward Secrecy is undesirable.


Please name a few of those sites that have  1024 DH keys.

I went looking for some more, but the apparently the only sites that have 
1024 DH keys are a few small sites usually concerning privacy and/or
security.

But I can understand that some people might prefer DHE instead of
ECDHE.  And I've actually requested that this cipher would be
enabled too.

Ah nice. I am not sure who is in charge of this decision, but I've searched
for a while and found quite a few sites that support AES-GCM but not the
ECDHE versions. The list includes VPN providers, a 3rd party payment
provider, a 3rd party system that educational institutions use which handles
student information and some more. So a lot of private and/or confidential
information. I hope that this can convince the need for
TLS_DHE_RSA_WITH_AES_*_GCM_SHA*

https://www.ssllabs.com/ssltest/analyze.html?d=openssl.orgs=185.9.166.106
https://www.ssllabs.com/ssltest/analyze.html?d=community.openvpn.net
https://www.ssllabs.com/ssltest/analyze.html?d=payment.buckaroo.nl
https://www.ssllabs.com/ssltest/analyze.html?d=hartvoorinternetvrijheid.nl
https://www.ssllabs.com/ssltest/analyze.html?d=system.im
https://www.ssllabs.com/ssltest/analyze.html?d=ivpn.net
https://www.ssllabs.com/ssltest/analyze.html?d=mullvad.net
https://www.ssllabs.com/ssltest/analyze.html?d=fronter.summacollege.nl
https://www.ssllabs.com/ssltest/analyze.html?d=proxy.sh
https://www.ssllabs.com/ssltest/analyze.html?d=unipackworldwide.com
https://www.ssllabs.com/ssltest/analyze.html?d=www.security.nls=213.156.0.246
https://www.ssllabs.com/ssltest/analyze.html?d=verified.de
https://www.ssllabs.com/ssltest/analyze.html?d=apache-da.com
https://www.ssllabs.com/ssltest/analyze.html?d=tuifly.com
https://www.ssllabs.com/ssltest/analyze.html?d=techzone.ergon.ch
https://www.ssllabs.com/ssltest/analyze.html?d=https-ict.nl
https://www.ssllabs.com/ssltest/analyze.html?d=filezilla-project.org
https://www.ssllabs.com/ssltest/analyze.html?d=socialsecurity.be
https://www.ssllabs.com/ssltest/analyze.html?d=daisy.ubuntu.coms=91.189.95.55
https://www.ssllabs.com/ssltest/analyze.html?d=www.box.coms=74.112.185.70

I understand that RSA is expected to get broken in the next 10 years
and we need alternatives.  ECDSA is currently the only other
standardised method for using in TLS that we should consider using
as far as I know.  I would also like to point out that EC isn't
exactly new, it's just seeing more wide deployment now.

So I'm actually concerned that in the long run all of RSA, DHE and
ECC will be broken and that we don't really have alternatives.
But we have to go with what we currently know.

Hopefully alternatives will emerge in the near future.




--
View this message in context: 
http://mozilla.6506.n7.nabble.com/Where-are-others-SHA256-cipher-suits-in-Firefox-27-tp306678p306864.html
Sent from the Mozilla - Cryptography mailing list archive at Nabble.com.
-- 
dev-tech-crypto mailing list
dev-tech-crypto@lists.mozilla.org
https://lists.mozilla.org/listinfo/dev-tech-crypto


Re: Where are others SHA256 cipher suits in Firefox 27?

2014-02-07 Thread Matthijs Janssen
Regarding the other variants of AES-GCM
-TLS_RSA_WITH_AES_128_GCM_SHA256
There are some sites support AES-GCM that use only ciphers with RSA key 
exchange. I think it would be best not to support new standards that don't 
provide Forward Secrecy, but on the other hand, if this cipher is enabled then 
users browsing to those sites will at least have something better than RSA with 
AES-CBC. If I'm correct, AES-GCM is not vulnerable to some of the newer TLS 
attacks, in particular Lucky13. Even when used together with TLS 1.2, AES-CBC 
is vulnerable to Lucky13.
-TLS_DHE_RSA_WITH_AES_128_GCM_SHA256
I'm aware that a lot of sites only use 1024 bit DH, but with the patent issues 
regarding ECC, there are still enough sites who don't support ECDHE. If this 
cipher is enabled, users can benefit both from protection against Lucky13 and 
Forward Secrecy. Also there are enough sites out there that do have 2048 or 
even 4096 bit DH key exchange. 
For sites that have both ECDHE and DHE ciphers enabled, ECDHE variants are 
usually the preferred anyway and if the server has no preference, they are also 
preferred by NSS. I also think that diversity should be maintained in case a 
vulnerability in some standard or protocol is discovered. Just like supporting 
ChaCha20_Poly1305 and AES with other modes like CCM to avoid the same disaster 
as with the BEAST attack, where AES-CBC was the only really secure protocol, 
found vulnerable and then having tons of sites switch back to the insecure RC4. 
Just in case ECC is being discovered vulnerable, there should be an alternative 
key exchange method that does not use EC cryptography. The only widely used are 
RSA and DHE, and DHE supports Forward Secrecy and is the better alternative 
IMO.  

Bruce Schneier believes ECC is relatively easier to break for the NSA. Whether 
or not you find his advice important, the fact is that ECC is relatively new 
and there should at least be one older and proven method as well.

As discussed before, ECC cryptography has better performance, but if webmasters 
prefer performance then they put DHE ciphers lower in the order  or disable 
them completely. IMO, the weighing whether to prefer performance or security is 
the choice of siteowners and webmasters. By supporting only variants you or 
someone else prefers, you're limiting their choice.
-- 
dev-tech-crypto mailing list
dev-tech-crypto@lists.mozilla.org
https://lists.mozilla.org/listinfo/dev-tech-crypto


Re: Where are others SHA256 cipher suits in Firefox 27?

2014-02-06 Thread Brian Smith
On Wed, Feb 5, 2014 at 9:54 PM, Rasj rasj...@gmail.com wrote:
 Where are others? For example:
 TLS_RSA_WITH_AES_256_CBC_SHA256 (0x3d)

See https://briansmith.org/browser-ciphersuites-01.html. Also, please
look at the archives of this mailing list. There have been several
DOZEN of emails about the cipher suite selection on this mailing list.

in particular: This proposal does not include the new HMAC-SHA256 or
HMAC-SHA384 ciphersuites that were added in TLS 1.2 since there is not
a clear need for them. Given our current understanding, HMAC-SHA-1,
HMAC-SHA-256, and HMAC-SHA-384 are all more-or-less equal in terms of
security given how they are used in TLS. (This is HMAC-SHA, not plain
SHA. Also, there is a huge difference in the ability to resist an
offline attack vs. the ability to resist an online attack.) Avoiding
these ciphersuites also allows us to sidestep the possibility of
performance regressions from enabling TLS 1.2.

 Many web-sites have only TLS_RSA_WITH_AES_256_CBC_SHA256 as kind of 
 strong(even without PFS) and weak RC4 and 3DES.

Please provide some examples of such sites.

Some of the information in my proposal is outdated. For example, it
seems like we don't have constraints on handshake size, since we've
discovered workarounds for those compatibility issues. So, we have
more flexibility to add these cipher suites than we previously did.

My main thought here is that these cipher suites aren't really
increasing security, but they are decreasing performance, when they
are used. We should advocate instead for cipher suites that increase
security and increase performance. That means, for example, cipher
suites that waste fewer bytes per record on nonces and padding. See
https://tools.ietf.org/html/draft-agl-tls-chacha20poly1305-04 for an
example of what I mean.

More generally, the CBC-HMAC mode of cipher suites is outdated and
should just be replaced. We have to support the older variants for
backward compatibility, but I don't see much reason, right now, to add
support for the new, less efficient, no-more-secure, variants.

Cheers,
Brian
-- 
Mozilla Networking/Crypto/Security (Necko/NSS/PSM)
-- 
dev-tech-crypto mailing list
dev-tech-crypto@lists.mozilla.org
https://lists.mozilla.org/listinfo/dev-tech-crypto


Re: Where are others SHA256 cipher suits in Firefox 27?

2014-02-06 Thread Rasj
On Thursday, February 6, 2014 12:50:16 PM UTC+4, Brian Smith wrote:
  Many web-sites have only TLS_RSA_WITH_AES_256_CBC_SHA256 as kind of 
  strong(even without PFS) and weak RC4 and 3DES.
 Please provide some examples of such sites.
Some Banks.


You can include it by default but turn it off if you worry about performance. 
So standard users get what you want and some users as I can turn it on in 
about:config. 

-- 
dev-tech-crypto mailing list
dev-tech-crypto@lists.mozilla.org
https://lists.mozilla.org/listinfo/dev-tech-crypto


Where are others SHA256 cipher suits in Firefox 27?

2014-02-06 Thread gegard4321-bugzi...@yahoo.co.uk
Regarding the other variants of AES-GCM
-TLS_RSA_WITH_AES_128_GCM_SHA256
There are some sites support AES-GCM that use only ciphers with RSA key 
exchange. I think it would be best not to support new standards that 
don't provide Forward Secrecy, but on the other hand, if this cipher is 
enabled then users browsing to those sites will at least have something better 
than RSA with AES-CBC. If I'm correct, AES-GCM is not vulnerable to some of the 
newer TLS attacks, in particular Lucky13. Even when used together with TLS 1.2, 
AES-CBC is 
vulnerable to Lucky13.
-TLS_DHE_RSA_WITH_AES_128_GCM_SHA256
I'm
 aware that a lot of sites only use 1024 bit DH, but with the patent 
issues regarding ECC, there are still enough sites who don't support 
ECDHE. If this cipher is enabled, users can benefit both from protection
 against Lucky13 and Forward Secrecy. Also there are enough sites out 
there that do have 2048 or even 4096 bit DH key exchange. 
For sites 
that have both ECDHE and DHE ciphers enabled, ECDHE variants are usually
 the preferred anyway and if the server has no preference, they are also
 preferred by NSS. I also think that diversity should be maintained in 
case a vulnerability in some standard or protocol is discovered. Just 
like supporting ChaCha20_Poly1305 and AES with other modes like CCM to avoid 
the same 
disaster as with the BEAST attack, where AES-CBC was the only really 
secure protocol, found vulnerable and then having tons of sites switch 
back to the insecure RC4. Just in case ECC is being discovered 
vulnerable, there should be an alternative key exchange method that does not 
use EC cryptography. The only widely used are RSA and DHE, and DHE 
supports Forward Secrecy and is the better alternative IMO.  
Bruce Schneier believes ECC is relatively easier to break for the NSA. Whether 
or not you find his advice important, the fact is that ECC is 
relatively new and there should at least be one older and proven method as well.

As
 discussed before, ECC cryptography has better performance, but if 
webmasters prefer performance then they put DHE ciphers lower in the 
order  or disable them completely. IMO, the weighing whether to prefer 
performance or security is the choice of siteowners and webmasters. By 
supporting only variants you or someone else prefers, you're limiting 
their choice.
-- 
dev-tech-crypto mailing list
dev-tech-crypto@lists.mozilla.org
https://lists.mozilla.org/listinfo/dev-tech-crypto


Re: Where are others SHA256 cipher suits in Firefox 27?

2014-02-06 Thread Kurt Roeckx
On Thu, Feb 06, 2014 at 09:57:34PM +, gegard4321-bugzi...@yahoo.co.uk wrote:
 Regarding the other variants of AES-GCM
 -TLS_RSA_WITH_AES_128_GCM_SHA256
 There are some sites support AES-GCM that use only ciphers with RSA key 
 exchange. I think it would be best not to support new standards that 
 don't provide Forward Secrecy, but on the other hand, if this cipher is 
 enabled then users browsing to those sites will at least have something 
 better than RSA with AES-CBC. If I'm correct, AES-GCM is not vulnerable to 
 some of the newer TLS attacks, in particular Lucky13. Even when used together 
 with TLS 1.2, AES-CBC is 
 vulnerable to Lucky13.

Lucky13 is a timing attack on MAC-then-Encrypt, which CBC uses.
This attack can be fixed, but it's harder to get this right than
it should be.

Maybe you're refering to the BEAST attack instead of Lucky 13,
which TLS 1.1 fixed and can be worked around in older versions
by splitting?

Anyway, I see no need for adding support for ciphers that do not
support forward secrecy.

 -TLS_DHE_RSA_WITH_AES_128_GCM_SHA256
 I'm
  aware that a lot of sites only use 1024 bit DH, but with the patent 
 issues regarding ECC, there are still enough sites who don't support 
 ECDHE. If this cipher is enabled, users can benefit both from protection
  against Lucky13 and Forward Secrecy. Also there are enough sites out 
 there that do have 2048 or even 4096 bit DH key exchange. 

Please name a few of those sites that have  1024 DH keys.

 For sites 
 that have both ECDHE and DHE ciphers enabled, ECDHE variants are usually
  the preferred anyway and if the server has no preference, they are also
  preferred by NSS. I also think that diversity should be maintained in 
 case a vulnerability in some standard or protocol is discovered. Just 
 like supporting ChaCha20_Poly1305 and AES with other modes like CCM to avoid 
 the same 
 disaster as with the BEAST attack, where AES-CBC was the only really 
 secure protocol, found vulnerable and then having tons of sites switch 
 back to the insecure RC4. Just in case ECC is being discovered 
 vulnerable, there should be an alternative key exchange method that does not 
 use EC cryptography. The only widely used are RSA and DHE, and DHE 
 supports Forward Secrecy and is the better alternative IMO.  

Some of the curves using by ECDHE might have some problems which
is why people are working on getting alternatives like curve25519
standardized.  But DHE is so slow that people want to avoid it,
and there are both clients and servers have problems with sizes
of 2048 or more which really is what you want.

But I can understand that some people might prefer DHE instead of
ECDHE.  And I've actually requested that this cipher would be
enabled too.

 Bruce Schneier believes ECC is relatively easier to break for the NSA. 
 Whether or not you find his advice important, the fact is that ECC is 
 relatively new and there should at least be one older and proven method as 
 well.

I understand that RSA is expected to get broken in the next 10 years
and we need alternatives.  ECDSA is currently the only other
standardised method for using in TLS that we should consider using
as far as I know.  I would also like to point out that EC isn't
exactly new, it's just seeing more wide deployment now.

So I'm actually concerned that in the long run all of RSA, DHE and
ECC will be broken and that we don't really have alternatives.
But we have to go with what we currently know.


Kurt

-- 
dev-tech-crypto mailing list
dev-tech-crypto@lists.mozilla.org
https://lists.mozilla.org/listinfo/dev-tech-crypto


Where are others SHA256 cipher suits in Firefox 27?

2014-02-05 Thread Rasj
Hi,
I see only:
TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 (0xc02b)
TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (0xc02f)

Where are others? For example:
TLS_RSA_WITH_AES_256_CBC_SHA256 (0x3d) 

Many web-sites have only TLS_RSA_WITH_AES_256_CBC_SHA256 as kind of strong(even 
without PFS) and weak RC4 and 3DES. If I have not 
TLS_RSA_WITH_AES_256_CBC_SHA256 server will choose RC4 or 3DES!

Why Mozilla doesn't add others SHA256 cipher suits? What is the problem to 
add them, is it so hard? :)
-- 
dev-tech-crypto mailing list
dev-tech-crypto@lists.mozilla.org
https://lists.mozilla.org/listinfo/dev-tech-crypto