Do the openssl X509_verify_cert() verifies the signature in the certificate?

c, linux, openssl

Solution

`X509_verify_cert()` essentially checks a certificate's validity. That includes verifying that signatures that have signed the cert belonging to CAs are valid and are in date - it'll process the entire chain like that.

It does not, however, verify that a given RSA signature is valid - although it validates RSA signatures as part of its work, it isn't what you should use to do that.

It is, broadly speaking, like the functionality that runs when you get a certificate error browsing an SSL site.

Problem

Do the openssl X509_verify_cert() API verifies the RSA signature in the certificate ? To my understanding , that API checks only certificate validity (like date check and all). Somebody please clarify ?

Original source