Safari (older than 14.1.1) rejects TLS connections of TURN with Let's Encrypt certificates

Summary

We could not make a video call successfully on Safari older than 14.1.1. The call kept disconnecting for some seconds. We got the following error in Nginx’s log

SSL: error:14094418:SSL routines:ssl3_read_bytes:tlsv1 alert unknown ca:SSL alert number 48

Root cause

The Safari didn’t trust our TLS certificates (certified by Let’s Encrypt) when establishing a TLS connection into our TURN server. It is a known issue that could be found at Bug 219274 - ICE does not resolve for `turns` relay candidates rooted in LetsEncrypt CA. The issue was just recently fixed (end of 2020), therefore old versions of Safari still meet the issues.

Solution

In our development environment, we replaced the untrusted certificate with a trusted one. We will warn our customers about this issue in our installation guide.

Technical explained

WebKit is a browser engine developed by Apple and primarily used in its Safari web browser, as well as all iOS web browsers. The WebRTC of WebKit relied on the upstream WebRTC library which the source code can be found here.

The WebRTC library contains its own hardcoded/fixed list of trusted root CA (Certification Authority). The list can be found here (source code). And, this list doesn’t contain the root CA of certificates generated by Let’s Encrypt.

In order to establish a TLS connection to our TURN server, Safari will verify the certificates are valid or not by using the WebRTC library. Therefore, the certificate verification was failed.

We needed to have a certificate with a root CA exist in the mentioned hardcoded list for a workaround. We just requested a free certificate from “ZeroSSL” which uses “USERTrust RSA Certification Authority” as its root CA. We can check the CA information of a certificate as the following command:

1openssl x509 -subject -issuer -noout -in /path/to/the/ca.pem

Or, by an online TLS checker such as SSL Checker.

The issue was fixed in the latest versions of WebKit so that there is no issue with the newest Safari. The status was updated at Bug 219274 - ICE does not resolve for `turns` relay candidates rooted in LetsEncrypt CA.

Comments

Styling Sort Icons Using Font Awesome for Primefaces' Data Table

So far, Primefaces has used image sprites for displaying the sort icons. This leads to a problem if we want to make a different style for these icons; for example, I would make the icon "arrow up" more blurry at the first time the table loading because I want to highlight the icon "arrow down". I found a way that I can replace these icons with Font Awesome icons. We will use "CSS Pseudo-classes" to achieve it. The hardest thing here is that we should handle displaying icons in different cases. There is a case both "arrow up" and "arrow down" showing and other case is only one of these icons is shown. .ui-sortable-column-icon.ui-icon.ui-icon-carat-2-n-s { background-image: none; margin-left: 5px; font-size: 1.1666em; position: relative; } .ui-sortable-column-icon.ui-icon.ui-icon-carat-2-n-s:not(.ui-icon-triangle-1-s)::before { content: "\f106"; font-family: "FontAwesome"; position: ...

Multiple Inheritance of State and Implementation

Today, I was just curious about why an enum can not extend anything else. I took a look on the Oracle document here , and I found the answer is below: "All enums implicitly extend java.lang.Enum. Because a class can only extend one parent (see Declaring Classes), the Java language does not support multiple inheritance of state (see Multiple Inheritance of State, Implementation, and Type), and therefore an enum cannot extend anything else." I have been learned of it before. But, wait a sec...! Why Java does not support multiple inheritance of state? Since I have worked with other programming languages like C++, I was able to make a class extend some other classes. The short answer is to avoid the issues of multiple inheritance of state . I wonder if other programming languages have these below terms but Java does. Multiple inheritance of state It is the ability to inherit fields from multiple classes. There is a problem and Java avoids it. "For exa...

JSF 2 - Dynamically manipulating the component tree with system events

Let's suppose we want to modify the metadata (attributes) of elements such as render , requried , maxlength but we do not define in JSF tags. The manipulating components can be conducted in Drools files, for example. How could we do? I think that is what we need to change something of component tree during JSF life-cycle. JSF supports event handling throughout the JSF life-cycle. In this post, I use two events: postAddToView for scanning components tree and preRenderView for manipulating the meta of components before rendering to GUI. I modified my own project from previous post for this example. This is my first further JSF trying out with the project as I said before. :) We define the tags f:event below the form - a container component of the components which we want to work on. The valid values for the attribute type for f:event can be found from tag library document of JSF 2. <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml" x...

Regex - Check a text without special characters but German, French

Special characters such as square brackets ([ ]) can cause an exception " java.util.regex.PatternSyntaxException " or something like this if we don't handle them correctly. I had met this issue. In my case, my customers want our application should allow some characters in German and French even not allow some special characters. The solution is that we limit the allowed characters by showing the validation message on GUI. For an instance, the message looks like the following: "This field can't contain any special characters; only letters, numbers, underscores (_), spaces and single quotes (') are allowed." I used Regular Expression to check it. For entering Germany and French, I actually don't have this type of keyboard, so I referred these sites: * German characters: http://german.typeit.org/ * French characters: http://french.typeit.org/ Here is my code: package vn.nvanhuong.practice; import java.util.regex.Matcher; import java.util...

The HelloWorld example of JSF 2.2 with Myfaces

I just did by myself create a very simple app "HelloWorld" of JSF 2.2 with a concrete implementation Myfaces that we can use it later on for our further JSF trying out. I attached the source code link at the end part. Just follow these steps below: 1. Create a Maven project in Eclipse (Kepler) with a simple Java web application archetype "maven-archetype-webapp". Maven should be the best choice for managing the dependencies , so far. JSF is a web framework that is the reason why I chose the mentioned archetype for my example. 2. Import dependencies for JSF implementation - Myfaces (v2.2.10) into file pom.xml . The following code that is easy to find from http://mvnrepository.com/ with key words "myfaces". <dependency> <groupId>org.apache.myfaces.core</groupId> <artifactId>myfaces-api</artifactId> <version>2.2.10</version> </dependency> <dependency> <groupId>org.apache.myfaces.core<...

vhandit

Search This Blog