# US 10,873,458 B2 · System and method for securely storing and utilizing password validation data

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 10,873,458 B2
- Document ID: US10873458B2
- Status: Granted
- Kind: B2
- Application number: 16/104,918
- Filed: 2018-08-19
- Published: 2018-12-20
- Granted: 2020-12-22
- Earliest claimed: 2016-04-28
- Applicants: Arnold G. Reinhold
- Inventors: Arnold G. Reinhold
- Web page: https://patentgrep.com/patent/US10873458B2

## CPC

- H04L 9/3226: {using a predetermined code, e.g. password, passphrase or PIN (network architectures or network communication protocols for supporting authentication of entities using passwords in a packet data network H04L63/083)}
- G06F 21/31: User authentication
- G06F 21/45: Structures or tools for the administration of authentication
- H04L 9/004: {for fault attacks}
- H04L 9/0643: {Hash functions, e.g. MD5, SHA, HMAC or f9 MAC}
- H04L 9/0662: {with particular pseudorandom sequence generator}
- H04L 9/3234: {involving additional secure or trusted devices, e.g. TPM, smartcard, USB or software token (network architectures or network communication protocols for supporting authentication of entities using an additional device in a packet data network H04L63/0853)}
- H04L 9/3239: {involving non-keyed hash functions, e.g. modification detection codes [MDCs], MD5, SHA or RIPEMD}
- H04L 63/083: {using passwords (cryptographic mechanisms or cryptographic arrangements for entity authentication using a predetermined code H04L9/3226)}
- H04L 63/1441: {Countermeasures against malicious traffic (countermeasures against attacks on cryptographic mechanisms H04L9/002)}
- H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M)
- G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N)

## Abstract

A system and method for storing and accessing password verification data on multi-user computer systems that prevents remote attacks. Along with commonly-employed measures that limit the number of unsuccessful attempts to login or otherwise verify a password, it allows users to choose relatively simple passwords with full security. The secret component cannot be easily leaked or exfiltrated does not require periodic backup and is isolated in a way that allows it to be protected by conventional security measures such as safes, alarm systems and video surveillance from attackers who somehow gain access to the computing facility.

## Claims

### Claim 1

A method for password authentication comprising:
obtaining a user id and a password as input on a password management module (PMM) comprising software executing on a processor configured to communicate with a restricted secret server (RSS);
generating a salt on the password management module;
securely sending a message including the salt to the RSS having a very large key (VLK) module;
wherein securely sending a message to the RSS comprises:
sending the message via a secure, authenticated link to at least one data guard;
authenticating the message on the at least one data guard; and
forwarding the message from the at least one data guard via a dedicated link to the RSS, wherein the at least one data guard is a module located within the RSS, and wherein the at least one data guard provides an interface between a restricted secret server network interface (RSS-NI) and the RSS;
generating a block of unpredictable data by a cryptographically-strong bit stream generator;
loading the block of unpredictable data into the VLK module;
using the salt included in the message as a seed for a deterministic random number generator (DRNG) on the restricted secret server;
using the seeded DRNG to select multiple subsets of data from the block of unpredictable data;
combining the multiple subsets of data from the block of unpredictable data to form a password authenticator token; and
securely sending a return message including the password authenticator token to the PMM, wherein securely sending a return message comprises:
sending the return message from the restricted secret server via a second dedicated link to the at least one data guard;
authenticating the return message on the at least one data guard; and
forwarding the return message via a secure, authenticated link to the PMM; and
wherein only the PMM can query the RSS using a secure link within one of:
a data center's intranet to access the RSS; and
a direct communication link between the PMM and the RSS.

### Claim 2 (depends on 1)

The method for password authentication of claim 1 further comprising:
sending information including at least one of:
user-specific information; and
enterprise-specific information, from the PMM to the RSS; and
using the information in addition to the salt to form the password authenticator token.

### Claim 3 (depends on 1)

The method for password authentication of claim 1, further comprising using the password authenticator field to authenticate the user id and the password received in a login attempt.

### Claim 4 (depends on 3)

The method for password authentication of claim 3 further comprising authenticating the password in one of:
the password management module; and
the restricted secret server.

### Claim 5 (depends on 1)

The method for password authentication of claim 1 further comprising:
limiting a rate at which messages are passed between the restricted secret server and the password management module such that the amount of data coming out of the RSS is limited.

### Claim 6 (depends on 5)

The method for password authentication of claim 5 wherein the VLK is a Terakey comprising a probabilistic random pad using a key having a size much larger than an anticipated volume of traffic.

### Claim 7 (depends on 1)

The method for password authentication of claim 1, wherein the VLK module is removable from the restricted secret server and further comprising:
providing a secure interlock between the VLK module and the restricted secret server.

### Claim 8 (depends on 7)

The method for password authentication of claim 7, wherein the removable VLK module is in a sealed unit designed to plug only into a corresponding restricted secret server.

### Claim 9 (depends on 8)

The method for password authentication of claim 8, wherein the sealed unit uses non-standard connector pin-outs and mechanical interlocks that are custom designed for each customer installation.

### Claim 10 (depends on 1)

The method for password authentication of claim 1 further comprising sending the message and return message between the password management module and the restricted secret server fixed in size to prevent buffer overflow attacks.

### Claim 11 (depends on 1)

The method for password authentication of claim 1, wherein transferring the block of unpredictable data takes longer than ten minutes which deters exfiltrating the block of unpredictable data out of the restricted secret server.

### Claim 12 (depends on 1)

The method for password authentication of claim 1 wherein the at least one data guard sanitizes data, enforces message formats and restricts the rate at which received from the RSS 120 are retransmitted to the PMM.

### Claim 13 (depends on 1)

The method for password authentication of claim 1 wherein the at least one data guard matches outputs with requests.

### Claim 14

A system for password authentication comprising:
a password management module (PMM);
a restricted secret server (RSS) having at least one very large key (VLK) module, a restricted secret server network interface (RSS-NI) interconnecting the RSS with the PMM and
a data guard disposed between the RSS-NI and the VLK module,
wherein the data guard is disposed between the RSS-NI and the at least one VLK storage module and is configured to restrict and sanitize request data by enforcing message formats and restricting the transfer rate of VLK data.

### Claim 15 (depends on 14)

The system of claim 14, wherein the VLK module further comprises a VLK module alarm which is triggered when the VLK module is removed from the RSS.

### Claim 16 (depends on 15)

The system of claim 15, wherein the VLK module alarm comprises an optical sensor.

### Claim 17 (depends on 14)

The system of claim 14, wherein the VLK module comprises a plurality of grooves and flutes to prevent insertion of an unauthorized VLK module into the RSS.

### Claim 18 (depends on 14)

The system of claim 14, wherein the VLK module includes storage which comprises one of:
a solid state drive (SSD);
a rotating hard disk; and
a NOR flash memory.

### Claim 19 (depends on 14)

The system of claim 14, wherein the VLK module comprises storage which comprises a memory device having non-standard firmware such that said memory device's control commands differ from standard control commands of a corresponding standard memory.

### Claim 20 (depends on 14)

The system of claim 14, wherein the data guard comprises a processor architecture wherein no data or code executed in the processor can affect its stored program and wherein the data guard uses non-standard connectors.