Meziantou.FrameworkSecurity
edit| To | Use | Page |
|---|---|---|
| Require a password to open a document, or restrict printing and copying | PdfDocument.Encryption | Encryption |
| Encrypt a document for the certificates of its recipients | PdfEncryptionRecipient | Encryption |
| Open an encrypted document | PdfReadOptions.Password, PdfReadOptions.Certificate | Encryption |
| Embed an encrypted document in a document that every reader opens | PdfDocument.SetEncryptedPayload | Unencrypted wrapper documents |
| Prove who approved a document, and that it did not change since | PdfSigner | Digital signatures |
| Check the signatures of a document | PdfSignatureVerifier | Digital signatures |
Encryption and signatures protect different things. Encryption hides the content from those who do not have the password or the private key of a recipient; its permissions are honored by the readers, not enforced by the file. A signature does not hide anything: it proves that the signed bytes did not change, and binds them to the certificate of the signer, whom the application must decide to trust.
In this section
- Encryption: passwords or certificates, algorithms and permissions, and how to remove or change them.
- Unencrypted wrapper documents: an encrypted document embedded in a document that is not encrypted.
- Digital signatures: PAdES signatures and time stamps, and their verification.