Verifying Signed Oracle Instant Client RPM Packages

Use the rpm command to perform operations such as listing and verifying the signature fingerprint for Oracle Instant Client RPM packages for Oracle Linux 7 and Oracle Linux 8.

Ensure that the RPM signature fingerprint matches the expected key fingerprint and also verify the RPM package has a signature. Before you start this process, perform the following tasks:

List the installed keys on your system:
```
rpm -qa gpg-pubkey
```
The output of this command is similar to the following:
```
gpg-pubkey-ad986da3-5cabf60d
gpg-pubkey-16c083cd-49af3996
```
Import the GPG keys (optional):
```
rpm --import GPG-KEY
```
Note:
Depending on your verification purpose you can install any GPG keys in the RPM database on your system to verify the signed packages.

Scenario 1: To verify an RPM package that has a signature with the key not installed on the system by default

Run the rpm -qip command to check the Oracle Instant Client Basic RPM package fingerprint. For example, for Linux x86-64:

rpm -qip oracle-instantclient19.22-basic-19.22.0.0.0-1.x86_64.rpm | grep Signature

The output of this command is similar to the following:

warning: oracle-instantclient19.22-basic-19.22.0.0.0-1.x86_64.rpm: Header V3 RSA/SHA256 Signature, key ID 8d8b756f: NOKEY
Signature: RSA/SHA256, Mon 09 Jan 2023 07:38:06 PM GMT, Key ID bc4d06a08d8b756f

Run the rpm --checksig --verbose command to verify the package and print headers statuses and fingerprint details for the Oracle Instant Client Basic RPM package. For example, for Linux x86-64:
```
rpm --checksig --verbose oracle-instantclient19.22-basic-19.22.0.0.0-1.x86_64.rpm
```
The output of this command is similar to the following:
```
oracle-instantclient19.22-basic-19.22.0.0.0-1.x86_64.rpm: 
Header V3 RSA/SHA256 Signature, key ID 8d8b756f: NOKEY
```
This output verifies the Oracle Instant Client Basic RPM package signature by printing the key ID and returning NOKEY verification status as the GPG key with this ID is not present in the RPM key management system.

Scenario 2: To verify RPM package with both signature and key installed

Run the rpm -qip command to check the Oracle Instant Client Basic RPM package fingerprint. For example, for Linux x86-64:
```
rpm -qip oracle-instantclient19.22-basic-19.22.0.0.0-1.x86_64.rpm | grep Signature
```
The output of this command is similar to the following:
```
Signature: RSA/SHA256, Fri 06 Jan 2023 11:11:04 PM GMT, Key ID 82562ea9ad986da3
```
Run the rpm --checksig --verbose command to verify the package and print headers statuses and fingerprint details for Oracle Instant Client Basic RPM package. For example, for Linux x86-64:
```
rpm --checksig --verbose oracle-instantclient19.22-basic-19.22.0.0.0-1.x86_64.rpm
```
The output of this command is similar to the following:
```
oracle-instantclient19.22-basic-19.22.0.0.0-1.x86_64.rpm: 
Header V3 RSA/SHA256 Signature, key ID ad986da3: OK
    Header SHA256 digest: OK
    Header SHA1 digest: OK
    Payload SHA256 digest: OK
    V3 RSA/SHA256 Signature, key ID ad986da3: OK
    MD5 digest: OK
```
This output verifies the Oracle Instant Client Basic RPM package signature with the key and displays the fingerprint.