Encrypting Documents with OpenPGP
LibreOffice pode cifrar documentos empregando cifrado de chave pública OpenPGP. O documento cífrase empregando un algoritmo de cifrado simétrico.
LibreOffice pode cifrar documentos confidencialmente empregando OpenPGP. O documento cífrase empregando un algoritmo de cifrado simétrico que require unha chave simétrica. Cada chave simétrica emprégase só unha vez e recibe tamén o nome de chave de sesión. O documento e a súa chave de sesión son enviados ao destinatario. A chave de sesión debe ser enviada aos destinatarios para que saiban como descifrar o documento mais, para a protexer durante a transmisión vai cifrada coa chave pública do destinatario. Só a chave privada pertencente ao destinatario pode descifrar a chave de sesión.
LibreOffice emprega o software de OpenPGP instalado no computador. Se non dispón de software de OpenPGP terá que descargar e instalar un axeitado para o seu sistema operativo, posibelmente desde o seu almacén de aplicacións ou canle de distribución de software.
Here are some external GPG applications known to work with LibreOffice:
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gpg4win on Windows
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GPGTools on MacOS
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On Linux, usually already installed:
gnupg - a command line utility for signing, encrypting and key management.
Graphical applications for gnupg such as Seahorse (gnome), Kleopatra and KGpg (KDE).
gpgme - an application program interface (API) to develop applications with GPG.
You must define a personal pair of cryptography keys with the OpenPGP application. Refer to the OpenPGP software installed on how to create a pair of keys, it is usually the first step to execute after the software installation.
Configuración de cifrado do LibreOffice
Choose menu Cryptography area:
. In theEncrypting documents
OpenPGP encryption requires the use of the public key of the recipient and this key must be available in the OpenPGP key chain stored in your computer. To encrypt a document:
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Escolla
, -
Enter a name for the file.
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Mark the
checkbox. -
Click
. LibreOffice opens the OpenPGP public key selection dialog. -
Choose the public key of the recipient. You can select multiple keys at the time.
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Click
to close the dialog and save the file.
The file is saved encrypted with the selected public keys.
Only the private key belonging to the recipient can decrypt the document, unless you also encrypt for yourself.
Decrypting documents
You can only decrypt documents that have been encrypted with your public key. To decrypt a document:
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Open the document. An Enter password prompt shows.
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Enter the password of the OpenPGP private key. The document is decrypted and the contents is available.
Difference between document encryption with OpenPGP and Save with password
Both commands address confidentiality, but in different ways.
When you save a document with a password, you must remember the password inserted to open the document later. Anyone else that needs to open the document must also know the password used at save time. Therefore, the Save password must be transmitted to be known by other users.
Files encrypted with the save password cannot be decrypted unless the save password is supplied.
With document OpenPGP encryption, you define the set of users that can decrypt the document and you don’t need to send passwords through channels which security is unknown. Besides, the OpenPGP application manages the key chain of public keys more efficiently.