Is there a problem with the iOS system? The updated APP needs to be updated repeatedly

Did you guys know that yesterday, many iPhone users received a lot of App update notifications...

There have been many complaints from netizens on major social platforms, and it seems that quite a few users have been affected by this incident.

Could it be that today is an auspicious day, and everyone is pushing out new versions on the same day?

Of course it’s not such a coincidence. In fact, this update has not been released at all. . .

What it was like before the update, and what it is like after the update▼

This is amazing, what on earth is going on?

Many netizens began to speculate, saying that perhaps this wave of updates was to fix the problem that some software could not be opened a while ago.

A while ago, some netizens were unable to open the software directly. The prompt "This application is no longer shared with you" appeared and they needed to delete it and download it again before they could use it.

However, in addition to the software downloaded through Home Sharing, some software downloaded from the App Store are also affected.

Many netizens speculated that this was due to the expiration of the application certificate, or problems with other credentials shared by the application, and this time the batch update of the software was updating the certificates in the application.

So the question is, what is a certificate?

This certificate, to be precise, refers to a digital certificate, which is an identity certificate issued by Apple to these software to prove the legitimacy and integrity of the App content.

This feels a bit like our ID card. With an ID card, you can prove that you are yourself and prove your legal citizenship.

Digital signatures are implemented based on asymmetric encryption algorithms, which Shichao will briefly explain here.

First of all, when you go to Apple and ask for a digital certificate for your software, Apple will officially generate a set of encryption tools, including a public key (a key that is made public) and a private key (a key that is kept private). These two good friends are a pair that can decrypt and encrypt each other and are uniquely paired.

The private key is stored in the Apple backend, and the corresponding public key is embedded in every iOS device.

This is the foreword~

When requesting a certificate, public and private keys are generated▼

Okay, now let’s start the formal “certification process”.

Apple obtains the software information, uses a summary algorithm to calculate the summary of the original data, and then uses its own private key to encrypt the summary into ciphertext. The ciphertext is the digital signature. Finally, the signature is integrated with the original data and sent to the user.

When the user installs the app, the iOS system extracts the signature and uses the public key to decrypt the signature into a digest, which yields digest 1.

At the same time, the same digest algorithm is used to calculate the digest of the original data again to obtain digest 2.

The next thing is very simple, just compare abstracts 1 and 2.

If the original data has been modified, the calculated summary will definitely change and will not match.

In this way, users can be guaranteed that the software has not been tampered with when using it, and every software installed on iOS is officially approved by Apple.

However, this certificate, like our ID card, has a time limit. If the certificate expires, different problems will arise depending on the type of certificate.

Digital certificates are now widely used in the Internet world, and the accidents caused by them are endless.

In 2018, Taobao’s certificate expired, causing everyone who visited Taobao to receive a browser error saying that the link was not secure. . .

In May 2019, Symantec forgot to update the security certificate used to sign Firefox add-ons, causing Firefox users around the world to experience extension errors and become unusable. . .

If there really is a problem with the digital certificate, it would not be surprising if Apple fixed it with a wave of updates.

But so far Apple has maintained its traditional virtue: keeping silent. It has not come out to explain what is going on. So whether it is really the digital certificate that caused the problem remains to be seen. . .

Moreover, for the same app, some people must update it, while others don’t. It seems that whether or not to update depends entirely on one’s appearance.

Shichao only knew that after spending half a day updating more than 20 software, I opened the App Store again.

Another 24 updates popped up for me!!!!