2.4.3 Signature Checking Using Gpg4win for Windows

The Section 2.4.2, “Signature Checking Using GnuPG” section describes how to verify MySQL downloads using GPG. That guide also applies to Microsoft Windows, but another option is to use a GUI tool like Gpg4win. You may use a different tool but our examples are based on Gpg4win, and utilize its bundled Kleopatra GUI.

Download and install Gpg4win, and then load Kleopatra. The dialog should look similar to:

Figure 2.1 Kleopatra: Initial Screen

Next, add the MySQL Release Engineering certificate. Do this by clicking File, Lookup Certificates on Server. Type "Mysql Release Engineering" into the search box and press Search.

Figure 2.2 Kleopatra: Lookup Certificates on Server Wizard: Finding a Certificate

Select the "MySQL Release Engineering" certificate. The Fingerprint and Key-ID must be "3A79BD29" for MySQL 5.7.37 and higher or "5072E1F5" for MySQL 5.7.36 and earlier, or choose Details... to confirm the certificate is valid. Now, import it by clicking Import. An import dialog is displayed; choose Okay, and this certificate should now be listed under the Imported Certificates tab.

Next, configure the trust level for our certificate. Select our certificate, then from the main menu select Certificates, Change Owner Trust.... We suggest choosing I believe checks are very accurate for our certificate, as otherwise you might not be able to verify our signature. Select I believe checks are very accurate to enable "full trust" and then press OK.

Figure 2.3 Kleopatra: Change Trust level for MySQL Release Engineering

Next, verify the downloaded MySQL package file. This requires files for both the packaged file, and the signature. The signature file must have the same name as the packaged file but with an appended .asc extension, as shown by the example in the following table. The signature is linked to on the downloads page for each MySQL product. You must create the .asc file with this signature.

Table 2.2 MySQL Package and Signature Files for MySQL Installer for Microsoft Windows

File Type	File Name
Distribution file	mysql-installer-community-5.7.44.msi
Signature file	mysql-installer-community-5.7.44.msi.asc

Make sure that both files are stored in the same directory and then run the following command to verify the signature for the distribution file. Either drag and drop the signature (.asc) file into Kleopatra, or load the dialog from File, Decrypt/Verify Files..., and then choose either the .msi or .asc file.

Figure 2.4 Kleopatra: The Decrypt and Verify Files Dialog

Click Decrypt/Verify to check the file. The two most common results look like the following, and although the yellow warning looks problematic, the following means that the file check passed with success. You may now run this installer.

Figure 2.5 Kleopatra: the Decrypt and Verify Results Dialog: All operations completed

Seeing a red "The signature is bad" error means the file is invalid. Do not execute the MSI file if you see this error.

Figure 2.6 Kleopatra: the Decrypt and Verify Results Dialog: Bad

The Section 2.4.2, “Signature Checking Using GnuPG” section explains why you probably don't see a green Good signature result.