US 6,819,766 B1 · Method and system for managing keys for encrypted data

Abstract

A computer system and method manages encryption keys for data. The system and method generates a session key and encrypts given data with the session key. The system and method generates a key encryption key based on a secret initial vector, or password. The session key is encrypted using the key encryption key. The encrypted data and the encrypted session key are then interleaved according to a set of indices created by a one-way transform. The one-way transform takes as its input the initial vector, the length of the encrypted session key and the length of the encrypted data. The data is recovered by a party knowing the initial vector using the one-way transform to determine the location of the encrypted session key in the interleaved data. The session key is decrypted which allows the data to be decrypted.

Claims22

Dependent claims

A method for managing encryption keys for data comprising the steps of:

a) generating a session key;
b) encrypting the data using the session key, the encrypted data having a binary representation;
c) generating a key encryption key based on an initial vector, the initial vector being known only to a party encrypting the data and a party intended to decrypt the data;
d) encrypting the session key using the key encryption key, the encrypted session key having a binary representation;
e) generating a set of indices by a one-way transform mapping based on the length of the binary representation of the encrypted session key, the length of the binary representation of the encrypted data, and the initial vector;
and
f) reformatting the binary representation of the encrypted data to generate an output set of binary data by interleaving the encrypted session key with the encrypted data by dividing the binary representation of the encrypted session key into segments and inserting the segments into the binary representation of the encrypted data at locations determined by the set of indices.

4 more elements

A method for managing encryption keys in a computer system environment having a client and a server, comprising the steps of:

a) authenticating communication between the client and the server;
b) securely communicating an initial vector to the client and the server;
c) defining a server application and a client application in the server, whereby the client application comprises computer code, for a set of data, for the following functions:
i) generating a session key;
ii) encrypting the set of data using the session key, the encrypted data having a binary representation;
iii) generating a key encryption key based on the initial vector;
iv) encrypting the session key using the key encryption key, the encrypted session key having a binary representation;
v) generating a set of indices by a one-way transform mapping based on the length of the binary representation of the encrypted session key, the length of the binary representation of the encrypted data, and the initial vector;
and
vi) reformatting the binary representation of the encrypted data to generate an output set of binary data by interleaving the encrypted session key with the encrypted data by dividing the binary representation of the encrypted session key into segments and inserting the segments into the binary representation of the encrypted data at locations determined by the set of indices;
and whereby the client application comprises computer code for the following functions:
vii) regenerating the set of indices by using the one-way transform mapping based on the length of the binary representation of the encrypted session key, the length of the binary representation of the encrypted data, and the initial vector;
viii) rebuilding the encrypted session key by using the regenerated set of indices to extract the segments of the binary representation of the encrypted session key from the output set of binary data and assembling the segments to form the encrypted session key;
ix) rebuilding the encrypted data by using the regenerated set of indices to extract the binary representation of the encrypted data from the output set of binary data;
x) regenerating the key encryption key, using the initial vector;
xi) regenerating the session key by decrypting the rebuilt encrypted session key using the regenerated key encryption key;
and
xii) decrypting the rebuilt encrypted data using the regenerated session key;
d) providing the client application to the client;
and
e) communicating between the client and the server by sets of data which are encrypted by the functions of the client application and decrypted by the functions of the server application.

18 more elements

A method for managing encryption keys for a plurality of sets of data comprising the steps of:

a) initializing an initial vector;
and
b) for each set of data:
i) generating an associated session key for the set of data using an encryption key generation algorithm whereby there is a low probability that more than two or more of the plurality of sets of data will share the same session key;
ii) encrypting the set of data using the associated session key, the encrypted set of data having a binary representation;
iii) generating a key encryption key for the associated session key, based on the initial vector;
iv) encrypting the associated session key using the key encryption key, the encrypted associated session key having a binary representation;
v) generating a set of indices for the set of data by a one-way transform mapping based on the length of the binary representation of the encrypted associated session key, the length of the binary representation of the encrypted set of data, and the initial vector;
and
vi) reformatting the binary representation of the encrypted set of data to generate an output set of binary data by interleaving the encrypted associated session key with the encrypted set of data by dividing the binary representation of the encrypted associated session key into segments and inserting the segments into the binary representation of the encrypted set of data at locations determined by the set of indices.

7 more elements

A computer system for managing encryption keys for data comprising:

a) means for generating a session key;
b) means for encrypting the data using the session key, the encrypted data having a binary representation;
c) means for generating a key encryption key based on an initial vector, the initial vector being known only to a party encrypting the data and a party intended to decrypt the data;
d) means for encrypting the session key using the key encryption key, the encrypted session key having a binary representation;
e) means for generating a set of indices by a one-way transform mapping based on the length of the binary representation of the encrypted session key, the length of the binary representation of the encrypted data, and the initial vector;
and
f) means for reformatting the binary representation of the encrypted data to generate an output set of binary data by interleaving the encrypted session key with the encrypted data by dividing the binary representation of the encrypted session key into segments and inserting the segments into the binary representation of the encrypted data at locations determined by the set of indices.

4 more elements

A computer program product for managing encryption keys in a computer system environment having a client and a server, comprising a computer usable medium having computer readable code means embodied in said medium to perform steps comprising:

a) authenticating communication between the client and the server;
b) securely communicating an initial vector to the client and the server;
c) defining a server application and a client application in the server, whereby the client application comprises computer code, for a set of data, for the following functions:
i) generating a session key;
ii) encrypting the set of data using the session key, the encrypted data having a binary representation;
iii) generating a key encryption key based on the initial vector;
iv) encrypting the session key using the key encryption key, the encrypted session key having a binary representation;
v) generating a set of indices by a one-way transform mapping based on the length of the binary representation of the encrypted session key, the length of the binary representation of the encrypted data, and the initial vector;
and
vi) reformatting the binary representation of the encrypted data to generate an output set of binary data by interleaving the encrypted session key with the encrypted data by dividing the binary representation of the encrypted session key into segments and inserting the segments into the binary representation of the encrypted data at locations determined by the set of indices;
and whereby the client application comprises computer code for the following functions:
vii) regenerating the set of indices by using the one-way transform mapping based on the length of the binary representation of the encrypted session key, the length of the binary representation of the encrypted data, and the initial vector;
viii) rebuilding the encrypted session key by using the regenerated set of indices to extract the segments of the binary representation of the encrypted session key from the output set of binary data and assembling the segments to form the encrypted session key;
ix) rebuilding the encrypted data by using the regenerated set of indices to extract the binary representation of the encrypted data from the output set of binary data;
x) regenerating the key encryption key, using the initial vector;
xi) regenerating the session key by decrypting the rebuilt encrypted session key using the regenerated key encryption key;
and
xii) decrypting the rebuilt encrypted data using the regenerated session key;
d) providing the client application to the client;
and
e) communicating between the client and the server by sets of data which are encrypted by the functions of the client application and decrypted by the functions of the server application.

18 more elements

Dependencies are inferred from the claim text.

Method and system for managing keys for encrypted data

Life of this patent

Method and system for managing keys for encrypted data

Life of this patent

Abstract

Claims22