Encryption, privacy and security

Data encryption in VIPole is always performed on the client side, and encryption keys are available to the user only. Data is transmitted encrypted to the web and to the server, and only the user can decrypt it. Therefore, no third party, including the service provider, can intercept or disclose the user data.

VIPole uses strong cryptographic algorithms for data protection:

AES-256 for symmetric encryption;
RSA with 3072 bit key for asymmetric encryption.

All messages are sent and stored on the server in secured VIPole containers. VIPole encrypted container includes symmetric and asymmetric encryption blocks and is based on the principle similar to S/MIME e-mail protection algorithm.

Protected data is encrypted with the symmetric algorithm using a one-time key of the container symmetric encryption;
VIPole ID of the sender , a one-time symmetric encryption key is encrypted with the asymmetric algorithm using the public key of the sender
VIPole ID of the receiver , a one-time symmetric encryption key is encrypted with the asymmetric algorithm using the public key of the receiver.

The original message is encrypted symmetrically (AES-256) using a one-time encryption key. The one-time encryption key is then encrypted asymmetrically (RSA) using the sender’s and the receivers’ public keys. Therefore, only the sender and the receivers can decrypt the one-time key with their private keys and then decrypt the message.

Encryption key management

Data protection level is defined not only by the encryption algorithm being used, but also by the system of creating, storing and transmitting encryption keys.

The core feature of VIPole security system is that only the users have access to the keys for decrypting their data. This is why no one else, including VIPole employees, is able to read the user data that is transferred and stored in the system.

	Purpose	Origin	Storage	Who has access
User password	Client access to VIPole server. Access to the account on VIPole website.	Created by user during sign up or when changing password.	Hashed on the server. Hashed on the device in the encrypted database.	User Server
One-time symmetric encryption key for secured VIPole container	Encryption of secured data using the symmetric encryption algorithm.	Generated automatically for each secured VIPole container.	Encrypted in secured VIPole container.	The sender of the secured VIPole container. The receivers of the secured VIPole container.
User’s public key	Encryption of one-time symmetric encryption keys for the secured VIPole containers.	Generated by the user together with the private key when creating the profile.	On the server. On the user’s device. In the contact lists of the users.	All users from the contact list
User’s private key	Decryption of one-time symmetric encryption keys for the secured VIPole containers. Decryption of other data, asymmetrically encrypted with user’s public key.	Generated by the user together with the public key when creating the profile.	Encrypted on the server. Encrypted on the user’s device.	Only the user
User’s secret phrase	Decryption of user’s private key	Generated by the user when creating the profile	Is not stored anywhere	Only the user

Data transmission

VIPole protects all transmitted data from interceptions and eavesdropping. Along with transferring data in secured containers, VIPole additionally protects data transmission channels.

VIPole uses two types of channels:

Client-server connections – basic connection to VIPole server, enabling all client-server interactions;
Direct user-to-user channels for voice and video transmission.

Connection	Connection type	Connection establishment
Basic connection to the server	VIPole protocol via protected TLS connection	VIPole server authentication is done by the client using the X.509 server certificate, installed on a client side. Client authorization: Client to server: connection request. Server to client: authorization request with a random passphrase (‘salt’). Client to server: reply to authorization request with hash value, calculated with received ‘salt’ and user’s login and password. Server to client: hash check, sending authorization status to the client.
Channels for voice and video calls	VIPole protocols	For each communication session one-time key material is generated that is used during the session to create one-time encryption keys for each packet. Each party encrypts this key material with the public key of the user and transmits it to the other party. The second part of the key material is generated using the Diffie-Hellman algorithm. This algorithm allows to generate the key material that is known to both parties, while the key material is not transmitted through the network. For each data packet the one-time encryption key is calculated using the packet data and the key material generated at the start of the communication session. Each data packet in the channel is symmetrically encrypted with the one-time key of the packet.

Data storage

VIPole stores all user data encrypted both on devices and on the server. Chat history, files and account information are stored in local encrypted databases on users’ devices.

Database encryption master key is generated at the database creation and is stored only on the device. The key is stored encrypted; the secret phrase and the private key of the user are used to decrypt it.

Data type	Transmission format	Data storage format on VIPole server	Data storage format on devices
Text messages	Secured VIPole container	Secured VIPole container	Secured VIPole database
Data stored in organizer and password manager, notes and tasks	Secured VIPole container	Secured VIPole container	Secured VIPole database
Voice and video communications	Secured VIPole channels	data is not stored	data is not stored
Files	Encrypted VIPole blocks in the special format	Encrypted VIPole blocks in the special format	Encrypted VIPole blocks in the special format

Encrypted database on the device

Each page of the user profile database is encrypted with the AES-256 symmetric encryption algorithm using a one-time key.

Key management	Access
Symmetric encryption master key is generated during VIPole profile creation on the device. Master key is used to generate one-time keys for encrypting each page of the database. Master key is stored on user’s device asymmetrically encrypted with the public key of the user. Master key is never sent to the server.	Each device has a unique master key, which means that the local database of the user is encrypted differently on different devices. Only the user has access to the master key: the master key is decrypted using with the private key after the user enters the secret phrase. The Group account allows setting the mode when the user is allowed to access the local database only after connecting to the server. In this case, the master key is additionally protected by the access mask, which is stored on the server and gets to the device only after the users connects to the server. As long as there is no connection to the server, it is impossible to figure out the master key and decrypt the database.

Key management

Access

Symmetric encryption master key is generated during VIPole profile creation on the device.
Master key is used to generate one-time keys for encrypting each page of the database.
Master key is stored on user’s device asymmetrically encrypted with the public key of the user.
Master key is never sent to the server.

Each device has a unique master key, which means that the local database of the user is encrypted differently on different devices.
Only the user has access to the master key: the master key is decrypted using with the private key after the user enters the secret phrase.
The Group account allows setting the mode when the user is allowed to access the local database only after connecting to the server. In this case, the master key is additionally protected by the access mask, which is stored on the server and gets to the device only after the users connects to the server. As long as there is no connection to the server, it is impossible to figure out the master key and decrypt the database.

Secure file storage

VIPole ensures the uniform protection for all user data stored in VIPole and transmitted via VIPole. Encryption is applied to files transferred via VIPole as well: files are not only transmitted encrypted, they are also stored encrypted on VIPole servers and on the devices of the users.

Special VIPole virtual drives are used for working with encrypted files on the user device. These drives are used to decrypt files when working with them in any program on the device.

	Encryption keys	Access
Storage on the server Each file is splitted into blocks, each block is symmetrically encrypted using a one-time encryption key	Symmetric encryption master key is generated for each file. One-time symmetric encryption key based on the master key is generated for each file block. File encryption master key is stored and sent in the secured VIPole container using the sender’s and receiver’s public keys.	For file’s sender – network access for deleting and downloading. For file’s receivers – network access for downloading. When the sender deletes the file, it is deleted for all receivers.
Storage on the device Each file is splitted into blocks, each block is symmetrically encrypted using a one-time encryption key	Symmetric encryption master key is generated for each file. One-time symmetric encryption key based on master key is generated for each file block. File encryption master key is stored in the local encrypted database on user’s device.	File access on the device is provided via VIPole virtual drive. The file is stored on the device encrypted, and the virtual disk allows to work with it like with a usual unencrypted file. On Android and iOS, files for reading are decrypted into temporary folders, which are automatically cleared after they are used.

Encryption and security architecture

Encryption key management

Data transmission

Data storage

Encrypted database on the device

Secure file storage

More about VIPole security