Key pair infrastructure for secure messaging

Patent metadata

Field	Value
Publication number	US-10356057-B2
Application number	US-201816192602-A
Country	US
Kind code	B2
Filing date	Nov 15, 2018
Priority date	Dec 14, 2016
Publication date	Jul 16, 2019
Grant date	Jul 16, 2019

Abstract

Embodiments of the present invention use a limited-use public/private key pair to encrypt and decrypt messages sent through an intermediary. The messages may contain sensitive information and may be transmitted between entities over one or more networks. In some embodiments, the entities and/or the networks may be untrusted. Nevertheless, the content of the messages may remain protected by virtue of the limited-use key pair infrastructure.

First claim

What is claimed is:

1. A verification server comprising:
a processor; and
a memory coupled to the processor, the memory storing instructions, which when executed by the processor, cause the verification server to perform operations including:
receiving, over a first network, a request for a public key from an access device, wherein the access device sends the request in response to an interaction with a client device;
generating the public key, a private key that corresponds to the public key, and a key identifier associated with the private key, wherein the public key and the private key are limited-use keys;
transmitting the public key and the key identifier to the access device, wherein the access device transmits the public key and the key identifier to the client device;
receiving, from the client device over a second network, a message and the key identifier from the client device, wherein the message is encrypted using the public key;
retrieving the private key associated with the key identifier;
decrypting the message using the private key;
generating a token in response to the message, wherein the token authorizes access to a resource;
generating a signature using the token and the private key; and
transmitting the token and the signature to the access device, wherein the access device validates the signature using the public key and the token.

2. The verification server of claim 1 , wherein the token is transmitted to the access device via the client device.

3. The verification server of claim 1 , wherein the token and the signature are transmitted to the access device via the client device.

4. The verification server of claim 1 , wherein the operations further include:
expiring the private key after generating the signature.

5. The verification server of claim 1 , wherein the private key associated with the key identifier is retrieved after determining that the key identifier has not expired.

6. The verification server of claim 1 , wherein receiving the request for the public key occurs after generating the public key, the private key, and the key identifier.

7. The verification server of claim 1 , wherein generating the public key, the private key, and the key identifier comprises generating a plurality of public keys including the public key, a plurality of private keys including the private key, and a plurality of key identifiers including the key identifier prior to receiving the request, and wherein after receiving the request, the operations further include:
selecting the public key from the plurality of public keys, the private key from the plurality of private keys, and the key identifier from the plurality of key identifiers.

8. A method comprising:
receiving, by a verification server over a first network, a request for a public key from an access device, wherein the access device sends the request in response to an interaction with a client device;
generating, by the verification server, the public key, a private key that corresponds to the public key, and a key identifier associated with the private key, wherein the public key and the private key are limited-use keys;
transmitting the public key and the key identifier to the access device, wherein the access device transmits the public key and the key identifier to the client device;
receiving, by the verification server from the client device over a second network, a message and the key identifier from the client device, wherein the message is encrypted using the public key;
retrieving the private key associated with the key identifier;
decrypting the message using the private key;
generating a token in response to the message, wherein the token authorizes access to a resource;
generating a signature using the token and the private key; and
transmitting the token and the signature to the access device, wherein the access device validates the signature using the public key and the token.

9. The method of claim 8 , wherein the token is transmitted to the access device via the client device.

10. The method of claim 8 , further comprising:
expiring the private key after generating the signature.

11. An access device comprising:
a processor; and
a memory coupled to the processor, the memory storing instructions, which when executed by the processor, cause the access device to perform operations including:
receiving a request to send a message from a client device;
in response to the request, requesting a public key from a verification server, wherein the verification server generates the public key, a private key that corresponds to the public key, and a key identifier associated with the private key, and wherein the public key and the private key are limited-use keys;
receiving the public key and the key identifier from the verification server;
transmitting the public key and the key identifier to the client device, wherein the client device encrypts the message using the public key and transmits the message and the key identifier to the verification server, and wherein the verification server retrieves the private key using the key identifier and decrypts the message using the private key, and wherein after the verification server decrypts the message using the private key, the verification server generates a token corresponding to the message and generates a signature using the token and the private key, wherein the token authorizes access to a resource, and wherein the operations further include:

receiving the token and the signature from the verification server; and
validating the signature using the public key.

12. A method comprising performing, by an access device:
receiving a request to send a message from a client device;
in response to the request, requesting a public key from a verification server, wherein the verification server generates the public key, a private key that corresponds to the public key, and a key identifier associated with the private key, and wherein the public key and the private key are limited-use keys;
receiving the public key and the key identifier from the verification server;
transmitting the public key and the key identifier to the client device, wherein the client device encrypts the message using the public key and transmits the message and the key identifier to the verification server, and wherein the verification server retrieves the private key using the key identifier and decrypts the message using the private key, and wherein after the verification server decrypts the message using the private key, the verification server generates a token corresponding to the message and generates a signature using the token and the private key, wherein the token authorizes access to a resource;
receiving the token and the signature of the private key from the verification server; and
validating the signature of the private key using the public key.

Assignees

• Visa Int Service Ass

Inventors

• John Rhidian
• Prokop Bartlomiej Piotr
• Looney Thomas

Classifications

• H04L9/0825 Primary

  using asymmetric-key encryption or public key infrastructure [PKI], e.g. key signature or public key certificates · CPC title

• H04L63/061

  for key exchange, e.g. in peer-to-peer networks (cryptographic mechanisms or cryptographic arrangements for key agreement H04L9/0838) · CPC title

• H04L9/088

  Usage controlling of secret information, e.g. techniques for restricting cryptographic keys to pre-authorized uses, different access levels, validity of crypto-period, different key- or password length, or different strong and weak cryptographic algorithms (network architectures or network communication protocols for using time-dependent keys in a packet data network H04L63/068) · CPC title

• H04L9/0891

  Revocation or update of secret information, e.g. encryption key update or rekeying · CPC title

• H04L9/3247

  involving digital signatures · CPC title