System, method and computer product for sending encrypted messages to recipients where the sender does not possess the credentials of the recipient

• US 20050257057A1
• Filed: 05/12/2004
• Published: 11/17/2005
• Est. Priority Date: 05/12/2004
• Status: Active Grant

• Current Assignee: ECHOWORX Corporation
• Original Assignee: ECHOWORX Corporation
• Inventors: Ivanov, Viatcheslav, Michael Sorbara, Joseph Dominic, Lai, Qinsheng, Mansell, Michael Graves, Roberts, Michael Albert
• Granted Patent: US 7,996,673 B2
• Time in Patent Office: Days
• US Class Current: 713/171
• CPC Class Codes: G06Q 20/383 Anonymous user system
• CPC Class Codes: H04L 2463/062 applying encryption of the keys
• CPC Class Codes: H04L 63/0435 wherein the sending and receiving network entities apply symmetric encryption, i.e. same key used for encryption and decryption cryptographic mechanisms or cryptographic arrangements for symmetric key encryption H04L9/06
• CPC Class Codes: H04L 63/0442 wherein the sending and receiving network entities apply asymmetric encryption, i.e. different keys for encryption and decryption cryptographic mechanisms or cryptographic arrangements for public-key encryption H04L9/30
• CPC Class Codes: H04L 63/0823 using certificates cryptographic mechanisms or cryptographic arrangements for entity authentication involving certificates H04L9/3263
• CPC Class Codes: H04L 9/006 involving public key infrastructure [PKI] trust models network architecture or network communication protocol for supporting authentication of entities using certificates in a packet data network H04L63/0823
• CPC Class Codes: H04L 9/0822 using key encryption key
• CPC Class Codes: H04L 9/3247 involving digital signatures
• CPC Class Codes: H04L 9/3268 using certificate validation, registration, distribution or revocation, e.g. certificate revocation list [CRL]

Abstract

A system for encrypting and decrypting messages using a browser in either a web or wireless device or secure message client software for transmission to or from a web server on the Internet connected to an email server or message server for the situation where the sender does not possess the credentials and public key of the recipients. The encryption and decryption is conducted using a standard web browser on a personal computer or a mini browser on a wireless device, or message client software on either a personal computer or wireless devices such that messages transmitted to the web or wireless browser or message client software can be completed and encrypted and signed by the user such that encrypted and signed data does not require credentials and public key of the recipients. A method for delivering and using private keys to ensure that such keys are destroyed after use is also provided. A method of transmitting encrypted messages to a web or wireless browser or message client and decrypting and verifying such messages by recipients who do not possess or who are not enrolled in a PKI and do not have private keys. A method for authenticating the sender/user of the browser, and a method for accessing or generating public and private keys for encrypting and decrypting messages for recipients who are not enrolled in a public key infrastructure.

Claims

1. A method of exchanging PKI compliant messages between a sender and one or more recipients, whereby the sender is associated with a sender computer and each of the one or more recipients is associated with a recipient computer, whereby the sender does not have access to the PKI credentials of at least one of the one or more recipients, said at least one of the one or more recipients corresponding to a non-credentialed recipient, the method comprising the steps of:

(a) Activating a Public Key Cryptography utility linked to a browser or a client communication program, or forming part of the browser or the client communication program, the Public Key Cryptography utility being operable to perform one or more cryptographic operations consisting of encrypting/decrypting data, authenticating data, and/or authenticating a sender, decrypting and/or verifying data, the Public Key Cryptography utility thereby performing one or more of such cryptographic operations so as to create an encrypted message;

(b) Sender sending the encrypted message to the non-credentialed recipient;

(c) The Public Key Cryptography utility in response to (b);

(i) identifying that the sender does not have access to the PKI credentials of the non-credentialed recipient; and

(ii) thereby initiating the creation of a secret shared between the sender and the non-credentialed recipient; and

(d) The non-credentialed recipient using the shared secret to either;

(i) Obtain the encrypted message in a decrypted form in a secure session with a trusted intermediary;

or

(ii) Activate a further Public Key Cryptography utility on the recipient computer of the non-credentialed recipient or on a server computer, so as to access a private key linked to the encrypted message thereby enabling the Public Key Cryptography utility to decrypt the encrypted message.

2. The method claimed in claim 1, whereby the non-credentialed recipient accesses a private message key linked to the encrypted message so as to obtain the encrypted message in a decrypted form in a secure session with the server computer.

3. The method claimed in claim 1, comprising the further steps of (i) generating a public key/private key pair for encrypting the message, and (ii) using the shared secret to encrypt the private key.

4. The method claimed in claim 3, comprising the further step of storing the encrypted private key to the server computer.

5. The method claimed in claim 4, whereby recipient information and the shared secret is also stored to the server computer.

6. The method claimed in claim 1, whereby:

(a) the message is encrypted using a trusted intermediary using the encryption key(s) of the trusted intermediary;

(b) the trusted intermediary captures the shared secret and sends a notification to the recipient with instructions for retrieving the encrypted message; and

(c) the recipient is authenticated to the trusted intermediary by providing the shared secret, whereby the trusted intermediary decrypts the encrypted message and transmits it to the recipient in a secure session.

7. The method claimed in claim 1, whereby the encrypted message is decrypted and displayed to the recipient by:

(a) Obtaining a shared secret question;

(b) Providing the shared secret; and

(c) In response to (c) either (i) authenticating the recipient to the server computer and thereby obtaining the encrypted message in a decrypted form in a secure session or (ii) authenticating the-recipient to the Public Key Cryptography utility on the recipient computer or the server computer and thereby releasing the private key for decryption of the encrypted message.

10. The method of claim 6, comprising the further step of saving the encrypted private key to a server computer or saving the shared secret to the server computer.

11. The method claimed in claim 10, comprising the further step of the Public Key Cryptography utility encrypting the message with the public key.

12. The method claimed in claim 10, whereby the public key consists of a public key created for the message by the Public Key Cryptography utility for the message.

8. A method of exchanging PKI compliant messages between a sender and one or more recipients, whereby the sender is associated with a sender computer and each of the one or more recipients is associated with a recipient computer, whereby the sender does not have access to the PKI credentials of at least one of the one or more recipients, said at least one of the one or more recipients corresponding to a non-credentialed recipient, the method comprising the steps of:

(a) Activating a Public Key Cryptography utility linked to a browser or a client communication program, or forming part of the browser or the client communication program, the Public Key Cryptography utility being operable to perform one or more cryptographic operations consisting of encrypting/decrypting data, authenticating data, and/or authenticating a sender, decrypting and/or verifying data, the Public Key Cryptography utility thereby performing one or more of such cryptographic operations so as to create an encrypted message;

(b) Sender sending the encrypted message to the non-credentialed recipient;

(c) The Public Key Cryptography utility in response to (b);

(i) identifying that the sender does not have access to the PKI credentials of the non-credentialed recipient; and

(ii) thereby initiating the creation of a secret shared between the sender and the non-credentialed recipient; and

(d) The non-credentialed recipient using the secret to activate a further Public Key Cryptography utility on the recipient computer of the non-credentialed recipient so as to access a private key linked to the encrypted message thereby enabling the Public Key Cryptography utility to decrypt the encrypted message.

9. The method claimed in claim 8, further comprising the steps of:

(a) Creating a public key and private key for the encrypted message;

(b) Encrypting the private key with the shared secret;

(c) Delivering the encrypted private key to the Public Key Cryptography utility; and

(d) Providing the shared secret to the Public Key Cryptography utility, thereby releasing the private key.

13. A method of exchanging PKI compliant messages between a sender and one or more recipients, whereby the sender is associated with a sender computer and each of the one or more recipients is associated with a recipient computer, whereby the sender does not have access to the PKI credentials of at least one of the one or more recipients, said at least one of the one or more recipients corresponding to a non-credentialed recipient, the method comprising the steps of:

(a) Activating a Public Key Cryptography utility linked to a browser or a client communication program, or forming part of the browser or the client communication program, the Public Key Cryptography utility being operable to perform one or more cryptographic operations consisting of encrypting/decrypting data, authenticating data, and/or authenticating a sender, decrypting and/or verifying data, the Public Key Cryptography utility thereby performing one or more of such cryptographic operations so as to create an encrypted message;

(b) Sender sending the encrypted message to a server computer for delivery to the non-credentialed recipient;

(c) The Public Key Cryptography utility in response to (b);

(i) identifying that the sender does not have access to the PKI credentials of the non-credentialed recipient; and

(ii) thereby initiating the creation of a secret shared between the sender and the non-credentialed recipient; and

(d) The non-credentialed recipient using the secret to obtain the encrypted message in a decrypted form in a secure session with the server computer.

14. The method claimed in claim 13, comprising the further steps of:

(a) The sender sending the encrypted message to an email server or to a message server for delivery to the non-credentialed recipient;

(b) The message server creating a message notification notifying the non-credentialed recipient that the email server or the message server has received the encrypted message; and

(c) In response to (b), the non-credentialed recipient authenticating to a server or a trusted intermediary thereby obtaining access to the encrypted message in decrypted form in a secure session.

15. A system for exchanging PKI compliant messages between a sender and one or more recipients, whereby the sender does not have access to the PKI credentials of at least one of the one or more recipients, said at least one of the one or more recipients corresponding to a non-credentialed recipient, the system comprising:

(a) A first network-connected device associated with the sender, and a second network-connected device associated with the recipient, the first and second network-connected devices being operable to communicate with remote devices via a communication network; and

(b) The first network-connected device including a Public Key Cryptographic utility linked to a browser or a client communication program, or forming part of the browser or the client communication program, the Public Key Cryptography utility being operable to perform one or more cryptographic operations consisting of encrypting/decrypting data, authenticating data, and/or authenticating a sender, decrypting and/or verifying data, the Public Key Cryptography utility being operable to;

(i) Perform one or more of such cryptographic operations so as to create an encrypted message for communication to the recipient; and

(ii) Identify that the sender does not have access to the PKI credentials of the non-credential recipient, and thereby initiating the creation of a secret shared between the sender and the non-credentialed recipient; and

Wherein the Public Key Cryptographic utility cooperates with a server to invite the recipient to provide the shared secret so as to;

(i) obtain the encrypted message in a decrypted form in a secure session with the server;

or (ii) activate a Public Key Cryptography utility linked to the second network-connected device or to the server so as to access a private key linked to the encrypted message thereby enabling the Public Key Cryptography utility to decrypt the encrypted message.

16. The system claimed in claim 15, wherein the Public Key Cryptography utility is operable on the first network-connected device to:

(a) Create a public key and private key for the encrypted message; and

(b) Encrypt the private key with the shared secret.

17. The system as claimed in claim 15, wherein:

(a) The Public Key Cryptography utility linked to the first network-connected device is operable to send the encrypted message to the server;

(b) The server is linked to a server application that is operable to create a message notification notifying the non-credentialed recipient that the server computer has received the encrypted message, and including instructions for the non-credential recipient retrieving the encrypted message; and

(c) The second network-connected device includes instructions for authenticating to the server, thereby instructing the server to decrypt the encrypted message and transmit same to the second network-connected device in a secure session.

18. A computer program product operable on a network-connected device for exchanging PKI compliant messages between a sender and one or more recipients, whereby the sender does not have access to the PKI credentials of at least one of the one or more recipients, said at least one of the one or more recipients corresponding to a non-credentialed recipient, the system comprising:

(a) A Public Key Cryptographic utility linked to a browser or a client communication program, or forming part of the browser or the client communication program, the Public Key Cryptography utility being operable to perform one or more cryptographic operations consisting of encrypting/decrypting data, authenticating data, and/or authenticating a sender, decrypting and/or verifying data, the Public Key Cryptography utility being operable on a computer of the sender to;

(i) Perform one or more of such cryptographic operations so as to create an encrypted message for communication to the recipient; and

(ii) Identify that the sender does not have access to the PKI credentials of the non-credentialed recipient, and thereby initiate the creation of a secret shared between the sender and the non-credentialed recipient; and

Wherein the Public Key Cryptographic utility cooperates with a server to invite the recipient to provide the shared secret so as to;

(i) obtain the encrypted message in a decrypted form in a secure session with the server;

or (ii) activate a Public Key Cryptography utility linked to the second network-connected device or to the server so as to access a private key linked to the encrypted message thereby enabling the Public Key Cryptography utility to decrypt the encrypted message.

19. The computer program product claimed in claim 18, wherein the Public Key Cryptography utility is operable to:

(a) Create a public key and private key for the encrypted message;

(b) Encrypt the private key with the shared secret.

20. The computer program product claimed in claim 18, wherein the Public Key Cryptography utility is operable on a computer associated with the recipient to:

(a) Obtain a question associated with the shared secret;

(b) Deliver the shared secret as an answer to the question, thereby authenticating the non-credentialed recipient to a server computer thereby obtaining access to the encrypted message in decrypted form in a secure session, or activating a Public Key Cryptography utility on a server computer or on the recipient computer to release the private key and thereby decrypt the message.