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Posts tagged with "New in Kestrel"

More testing: Updated EV information and new Roots

Friday, 18. April 2008, 18:22:12

A few hours ago the new online certificate repository that the most recent weeklies are using was updated with several new roots, and an additional CA, Comodo, was also provisionally EV-enabled

The new and the updated CAs are

America OnLine
Cisco
Comodo
Digicert

There is no need to download an updated Weekly (if you have one of the two recent ones). When you next restart one of the Opera 9.50 Weeklies with support for online certificate updates, it will immediately download the indexes, and download the new certificates when necessary. Please give it a minute to finish the update.

Here are a couple of testsites:

AOL: https://new.aol.com/ . This site will verify in newer versions, but not in older (Warning about issuer). Known problem: The security level is low due to problems with the CRL (Unsupported format, and currently no plans to support it. The connection will fail in the first build). AOL is aware of the problem, and was already working on updating their CRL system
Comodo EV sites:
https://www.sslcertificaten.nl/
https://comodocertificationauthority-ev.comodoca.com/
https://secure.comodo.com/example.html

Known Issues: The complex certificate chain system used by Comodo encounters some, mostly hidden, problems with our OpenSSL certificate verification support, and that will cause some EV sites to not be recognized. We will try to fix it, but it may not be advisable to include a fix in 9.50.
[*] DigiCert:

https://vpn.osrmedical.com/Citrix/AccessPlatform1/auth/login.aspx In older versions this will validate to an Entrust root (see in the Certificate details view of the security toolbar dialog), after this remote update of 9.50 the root will instead be "Digicert High Assurance".
https://www.iwanttss.com/ In older versions this site will trigger an unknown issuer warning, after this update it will also validate to "Digicert High Assurance"

I do not currently have testcases for Cisco, as they have not yet started issuing certificates from the new root.

More about known issues:

We know there are some problems with OCSP and CRL responses (the two kinds of revocation information) from some Certificate Authorities. These problem may lead to the website getting a lower security level. We are looking into these problems together with the CAs. In last week's build some of the CRL problems will cause a "Fatal Error 50", in the most recent build that has been fixed. We may decide to work around some of these, but they should preferably be fixed by the CA.
At least one CA (who is not in our repository) is using CRLs with a critical extension, which will cause the secure connection to fail with error code 554. In this case we are following the standard, although one might wonder why the specification says "Although the extension is critical, conforming implementations are not required to support this extension". The problem have been "fixed" internally by recognzing the extension, then ignore it, as we do not need it.

16 comments

New in Kestrel: Faster Root Certificate updates

Tuesday, 8. April 2008, 15:55:26

browser statistics, New in Kestrel, Security, standards ...

Extended Validation (EV) is not the only new feature in the most recent Weekly; we've also improved the certificate database by making it able to download new Roots automatically. This means that we can add new Roots to the Certificate Authority database without requiring users to update their installation.

Root Certificates are one the fundamental pillars of Internet security. They are used to confirm the identity of secure webservers by acting as a trusted third party. The introduction of a third party is what makes it possible for two parties that have had no previous contact to determine who the other is, and, based on that, establish an encrypted connection. That is the true "magic" of Public Key Cryptography.

The problem with Root Certificates has been that before they can be used, each relying party (in particular, TLS clients, as in our case) must have a copy of it. If a party doesn't have a trusted copy of the Root it cannot verify the certificate that the other party sent, and can therefore not make any statement about the identity, nor establish a secure connection to that other party.

In SSL/TLS clients like Opera, much of this initial problem has been handled by the vendor shipping a list of trusted Roots with each installation, as well as some update mechanism to add new Roots when necessary. In Opera, this update mechanism has until now been rather crude, as a new version of Opera would have to be installed by each user.

In this Weekly, we are adding an automatic certificate download capability that works like this:

A number of frequently used Roots are still shipped with Opera.
If a Web site presents a certificate issued from a Root that is not in the local Certificate store, but is available in the online repository, it will be downloaded and installed in the repository. (Please note that this means that if you delete a certificate rather than marking it as untrusted, it will be downloaded again if necessary.)
If a Root is added to the repository, and is closely associated with another Root, we can instruct all Opera instances to download that root if they have the other Root. This is particularly important in relation to how EV certificate chains have to be organized.

The certificates are downloaded from a repository hosted at https://certs.opera.com/, which is also the server hosting the EV information, and the information is refreshed every 6 hours. The certificate files hosted on this server, whose names are constructed from a SHA-256 digest of the CA name and other information that uniquely identifies them, are all digitally signed to prevent forgery.

A separate list in the repository identifies all the certificates that are included in the repository. This list is used to stop Opera from checking the repository for unknown issuers. The list is currently retrieved every time Opera starts, but will later be checked when Opera checks for other updates, that is, once a week when Opera starts.

We are particularly interested in your experiences with this new functionality and would like you to test it in various environments, such as:

performing an upgrade of a used test installation of 9.2x
clean installs,
whether or not secure sites that worked in 9.2x and previous Kestrel Weeklies work OK in this build.

Also, somebody may ask, "Does this mean Opera now have the ability to automatically remove a Root certificate?". Yes, in extreme cases, such as the unlikely event (I hope) of a Root Key compromise, we now have the ability to do what previously would have required an emergency security update.
We also have the ability to add certificates to the new "Untrusted" certificate store, which might be necessary in cases where an important certificate has been issued in error.

11 comments

New in Kestrel: End of the Extended (Validation) wait

Tuesday, 8. April 2008, 15:54:39

standards, New in Kestrel, Kestrel, Extended Validation ...

Today we're releasing the first Kestrel Weekly with Extended Validation (EV) support.

As I've written before, Extended Validation is a new way to indicate, in a Web site certificate, that the identity of the company behind the Web site has been verified according to a rigorous standard. The guidelines for this process is defined by the CA/Browser forum, which is a group consisting of many certificate issuers (CAs), browser vendors, and others.

We are now ready to start public alpha testing.

So, how does it work?

When a Web site is recognized as an EV site, Opera will change the background color of the security toolbar to green, instead of yellow as it is for normal secure Web sites. There will be a few further adjustments done in this area, the most major being that we have stopped displaying the Organization Name field and country in the security toolbar for non-EV sites, because this name might not have been properly verified for non-EV certificates.

What is required to be permitted to issue EV certificates?

Root CAs that want to issue EV certificates must first pass a rigorous audit to prove that they have the proper procedures in place to identify accurately the company requesting a certificate, and that this company is in control of the given server. Further, an agreement between the Root CA and the browser vendor is required before the browser can recognize the CA's certificates as EV certificates.

How does Opera know it is an EV certificate?

All EV certificates contain an identifier (called an EV-OID, actually a Certificate Policy identifier). The CA will insert this identifier when it has verified all the information. Only certificates issued from specific Roots are allowed to use these identifiers.

How does Opera know that a Root is allowed to issue EV certificates?

Each Opera instance will regularly download a digitally-signed list identifying the CA, its certificate, and which EV-OID(s) it is permitted to use (different CAs can use different EV-OIDs). When Opera verifies a certificate issued from this Root, it will "sift" through the data where the EV-OIDs are stored to see if it contains one of the EV-OIDs recognized for this Root. If such an EV-OID is present, Opera will proceed to check if the other requirements (see below) for saying the Web site is an EV site are fulfilled.

What is required by a Web site to be considered an EV site?

The primary requirement is, of course, that it is eligible to get an EV certificate, and that it has purchased and installed one. The certificate, and all the intermediate certificates must (of course) still be valid, and cannot have been revoked by the issuer (we now check both OCSP and CRLs). Further, there must be no problems verifying the certificate; that is, there must be no unknown issuers, no mismatch of server name, and no weak encryption.

There are also a couple of specific encryption key requirements: The Web site's key should (for RSA) be at least 2048 bits long, but non-root certificates which expire before 23:59:59 UTC/GMT December 31, 2010 MAY use RSA keys of at least 1024 bits. Except for the Root key, which (for RSA) must be at least 2048 bit long, all signing keys must be at least as long as the key of the certificate it is used to sign.

And lastly, if the Web site includes content from other Web servers, those servers must *also* be hosting EV-sites. This is a point at which we are much stricter than the other EV-capable browsers currently. As I said earlier: "It ain't EV 'til it is EV, all EV".

The reason for this requirement is that these other servers may provide content that directly controls the appearance of the entire site, either through frames or external Ecmascript embedded in the page (and the latter has full control of the site's content).

Considering how many click-wrap licensed Web services (such as for Web statistics) there are, it is not likely that the Web designers signing their sites up for these services will have done anything close to good-enough legal identity check of the service. Also, don't forget all the liability disclaimers such contracts include. It is impossible to check the contracts, but we can check that the sites have been able to get an EV certificate.

EV is intended to give you better information about who provided the content with which you are viewing and interacting. If not all the servers providing the content are providing this kind of information, do you really know who provided the important part of the content? Our answer is that you don't, therefore such sites, which at the moment include Paypal.com, will not get the EV indication unless they either remove all references to the non-EV content, or those providers upgrade to provide EV content, as well.

Which Root CAs are currently recognized as issuing EV certificates?

During the test period starting with this release we have provisonally configured three Roots as EV Roots (in alphabetic order)

Entrust's EV Root
GlobalSign's EV Root
VeriSign's G5 Class 3 (EV) Root

Other CAs and Roots may be added later.

About the online repository

As mentioned above, Opera retrieves information about which CAs are recognized as EV-issuers from an online repository. This repository, hosted at https://certs.opera.com/, contains a digitally-signed file listing all the EV issuers and a (separately) signed list of the EV-OIDs they are using.

This repository is refreshed every 6 hours, so we can start updating clients very quickly. At present Opera will check this repository immediately when it starts, but the final version will only check once a week at the same time as we check for other updates.

Examples of EV sites