公开(公告)号：US10735384B2

公开(公告)日：2020-08-04

申请号：US15649929

申请日：2017-07-14

Applicant: WhatsApp, Inc.

Inventor： Derek Alan Konigsberg ,  George Nachman ,  Chun Wing Yuen ,  Ehren Andrew Kret

IPC: H04L29/06 ,  G06F21/60 ,  H04W12/02 ,  H04L9/08 ,  H04L9/32

Abstract: Techniques for key ratcheting with multiple step sizes are described. For example, an apparatus may be configured to receive two or more encrypted messages, where the encrypted messages are encrypted according to a multi-dimensional ratcheting encryption scheme. Moreover, the apparatus may be configured to determine which of the encrypted messages was most-recently received and extract a message iteration count from the most-recent encrypted message, generate a decrypted message by decrypting the encrypted message based on a decryption key, decompose the message iteration count into a plurality of message chain key iteration counts, and determine the decryption key based on the plurality of message chain key iteration counts.

公开(公告)号：US20180241725A1

公开(公告)日：2018-08-23

申请号：US15649929

申请日：2017-07-14

Applicant: WhatsApp, Inc.

Inventor： Derek Alan Konigsberg ,  George Nachman ,  Chun Wing Yuen ,  Ehren Andrew Kret

IPC: H04L29/06 ,  G06F21/60

Abstract: Techniques for key ratcheting with multiple step sizes are described. In one embodiment, an apparatus may comprise a messaging component operative to receive an encrypted message, the encrypted message encrypted according to a multi-dimensional ratcheting encryption scheme; determine a message iteration count for the encrypted message; and generate a decrypted message by decrypting the encrypted message based on a decryption key; and a key management component operative on the processor circuit to decompose the message iteration count into a plurality of message chain key iteration counts; and determine the decryption key based on the plurality of message chain key iteration counts. Other embodiments are described and claimed.