Signing OpenOffice.org 3 Document Failed

PKI Tutorials - Herong's Tutorial Examples

∟Signing OpenOffice.org 3 Document Failed

This section provides a tutorial example on how OpenOffice.org 3 refuses to use a certificate that was issued from an invalid intermediate CA. Be an intermediate CA, your certificate must have authorized usage of 'Certificate Signing, Off-line CRL Signing, CRL Signing (06)'.

Amy is ready to apply digital signatures to OpenOffice.org 3 documents now. So she follows the instruction from OpenOffice.org 3 help text:

1. Amy runs OpenOffice.org 3 Writer and creates a document called Digital-Signature-Test.odt.

2. Click "Digital Signatures" from the "File" menu. The "Digital Signatures" dialog box shows up.

3. Click "Add" button. The "Select Certificate" dialog box shows up. Amy's certificate is listed there.

3. Select Amy's certificate and click "OK" button. But no digital signature is added! Why?

Adding Digital Signatures in OpenOffice.org 3

4. Amy goes back to "Internet Options" and view Amy's certificate.

5. Select "herongyang.com" on the "Certificate Path" tab. This message shows up in the certificate status section:

This certificate does not appear to be valid for the selected purpose.

6. Double clicks "herongyang.com" on the "Certificate Path" tab. My certificate shows up with this information on the "General" tab:

This certificate is intended for the following purpose(s):
- Proves your identify to a remote computer
- Ensures the identity of a remote computer
- Allows strong encryption for online transactions/communications

I think I understand why OpenOffice.org refuses to use Amy's certificate to sign the document. The root cause of the problem is my certificate, which is issued by CAcert.org with 3 specific purposes. Acting as intermediate CA and issuing certificates to others is not listed on my certificate. So in theory, I can not use my certificate from CAcert.org to sign other certificates.