Bug 1412611 – NSS should use P-256 for TLS by default, not new curves

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Bug 1412611 - NSS should use P-256 for TLS by default, not new curves

Summary:	NSS should use P-256 for TLS by default, not new curves

Status:	CLOSED ERRATA

Aliases:	None

Product:	Red Hat Enterprise Linux 7
Classification:	Red Hat
Component:	nss (Show other bugs)
Sub Component:
Version:	7.4
Hardware:	Unspecified Unspecified

Priority	unspecified Severity unspecified
Target Milestone:	rc
Target Release:	7.4
Assigned To:	Daiki Ueno
QA Contact:	Hubert Kario
Docs Contact:

URL:
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Depends On:
Blocks:
	Show dependency tree / graph

Reported:	2017-01-12 07:40 EST by Kai Engert (:kaie) (inactive account)
Modified:	2017-08-01 12:50 EDT (History)
CC List:	5 users (show)

See Also:
Fixed In Version:	nss-3.28.3-4.el7
Doc Type:	If docs needed, set a value
Doc Text:
Story Points:	---
Clone Of:
Environment:
Last Closed:	2017-08-01 12:50:07 EDT
Type:	Bug
Regression:	---
Mount Type:	---
Documentation:	---
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Verified Versions:
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oVirt Team:	---
RHEL 7.3 requirements from Atomic Host:
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Add an attachment (proposed patch, testcase, etc.)

External Trackers
Tracker	ID	Priority	Status	Summary	Last Updated
Mozilla Foundation	1330612	None	None	None	2017-01-12 07:41 EST
Red Hat Product Errata	RHEA-2017:1977	normal	SHIPPED_LIVE	nss bug fix and enhancement update	2017-08-01 13:57:47 EDT

Groups: None (edit)

Description Kai Engert (:kaie) (inactive account) 2017-01-12 07:40:53 EST

Hubert reported, the current behavior of NSS 3.28.x isn't ideal for our compatibility needs, and has suggested a change to use curve P-256 by default.

We'll need that fix (see upstream bug) for RHEL 7.4.0 which will pick up a new softokn that supports additional curves.

Comment 1 Tomas Mraz 2017-01-12 08:07:23 EST

The other option is to change the ciphersuite selection so when client does not send a group list the server chooses non-ecc ciphersuite. That's what openssl will do in future releases.

Comment 2 Kai Engert (:kaie) (inactive account) 2017-01-12 08:27:11 EST

Tomas, thanks for your suggestion. The implementation discussion is happening upstream. We either have to forward your suggestion, or you could participate directly in the upstream NSS bug. Preference?

Comment 3 Tomas Mraz 2017-01-12 09:21:05 EST

I'll add a comment to the upstream bug.

Comment 4 Tomas Mraz 2017-01-12 09:23:49 EST

Hmm, I actually see that on the upstream bug the option to treat missing supported groups extension as no support for ecc is already discussed.

Comment 5 Kai Engert (:kaie) (inactive account) 2017-01-13 06:51:04 EST

The upstream bug has received a patch, so I think it's possible to backport it to the version we'll use in RHEL 7.4.0, adding devel-ack+

Comment 6 Hubert Kario 2017-01-13 06:57:37 EST

tlsfuzzer test cases implicitly test this, since current version doesn't support X25519, but writing a test case that expects P-256 in case no supported_groups are sent is trivial

Comment 7 Kai Engert (:kaie) (inactive account) 2017-02-24 09:14:22 EST

Daiki, could you please backport the upstream fix for 7.4.0 ?

Hubert, can you please help with qa-ack?

Comment 9 Daiki Ueno 2017-03-15 05:54:27 EDT

The upstream patch has already been backported to the 3.28 branch and included in the 3.28.2:
https://hg.mozilla.org/projects/nss/rev/970f503f579e

So rebasing to 3.28.3 should fix the issue.

Comment 12 errata-xmlrpc 2017-08-01 12:50:07 EDT

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHEA-2017:1977

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