Cryptographic system with halting key derivation function capabilities
US8254571B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 21, 2007 |
| Grant date | Aug 28, 2012 |
| Priority date | — |
| Expiry date | May 23, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L9/50
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A halting key derivation function is provided. A setup process scrambles a user-supplied password and a random string in a loop. When the loop is halted by user input, the setup process may generate verification information and a cryptographic key. The key may be used to encrypt data. During a subsequent password verification and key recovery process, the verification information is retrieved, a user-supplied trial password obtained, and both are used together to recover the key using a loop computation. During the loop, the verification process repeatedly tests the results produced by the looping scrambling function against the verification information. In case of match, the trial password is correct and a cryptographic key matching the key produced by the setup process may be generated and used for data decryption. As long as there is no match, the loop may continue indefinitely until interrupted exogenously, such as by user input.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.