verdnatura-chat/app/lib/encryption

Rocket.Chat Mobile

E2E Encryption

Note: This feature is currently in beta. Uploads will not be encrypted in this version. You can check this documentation for further information about the web client.

How it works

• Each user has a public and private key (asymmetric cryptography).
• The user private key is stored encrypted on the server and it can be decrypted on clients only using the user E2E encryption password.
• A room key is generated using the public key of each room member (symmetric cryptography).
• Users can decrypt the room key using their private key.
• Each room has a unique identifier which make users able to request a room key.
• The room unique identifier is called e2eKeyId and it's a property of the room collection.
• The room key is called E2EKey and it's a property of the subscription collection.
• After the room key is decrypted, the user is able to encrypt and decrypt messages of the room.

User keys

• If the user doesn't have keys neither locally nor on the server, we create and encrypt them using a random password. These encrypted keys are sent to the server (so other clients can fetch) and saved locally.
• If the user have keys stored on server, but doesn't have them stored locally, we fetch them from the server and request a password to decrypt the keys.

Room keys

• If the room has a E2EKey, we decrypt it using the user key.
• If the room doesn't have a E2EKey, but has a e2eKeyId, we emit an event on stream-notify-room-users sending the roomId and the e2eKeyId requesting the E2EKey from any online room member.
• If the room have none of them, we create new ones and send them back to the server.