Transparent encryption/decryption gateway for cloud storage services

• US 9,374,345 B2
• Filed: 06/05/2015
• Issued: 06/21/2016
• Est. Priority Date: 01/09/2013
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Brugger, Dominik W., Seul, Matthias
• Primary Examiner(s): HO, DAO Q
• Application Number:
  US14/731,505
• Publication Number:
  US 20150271151A1
• Time in Patent Office: 382 Days
• Field of Search: 713/154
• US Class Current: 1/1
• CPC Class Codes: G06F 21/60 Protecting data
• CPC Class Codes: H04L 63/0227 Filtering policies mail message filtering H04L51/212
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• 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 63/101 Access control lists [ACL]
• CPC Class Codes: H04L 63/1441 Countermeasures against malicious traffic countermeasures against attacks on cryptographic mechanisms H04L9/002

Abstract

A mechanism is provided for secure data storage in a distributed computing system by a client of the distributed computing system. A gateway device intercepts a data file from at least a portion of stream data during transmission. If the destination of the data file is the storage, the gateway device selects a set of analysis algorithms to determine whether the data file comprises sensitive data.

Claims

1. A computer implemented method for secure data storage in a storage in a distributed computing system by a client of the distributed computing system, the method comprising in a gateway device of the distributed computing system:

intercepting a data file from at least a portion of stream data during transmission of the stream data in the distributed computing system;

evaluating the data file for determining a communication protocol used for the stream data transmission;

evaluating the data file based on the communication protocol for determining a destination and a source of the data file;

responsive to determining the destination is the storage and the source is the client;

selecting a set of analysis algorithms from a plurality of predetermined analysis algorithms;

analyzing the data file using each of the analysis algorithms of the set of analysis algorithms for determining whether the data file comprises sensitive data;

in response to a determination that the data file comprises sensitive data, replacing payload content of the data file with encrypted payload data; and

transmitting the data file to the storage,

wherein replacing payload content of the data file with encrypted payload data comprises;

creating a data container;

encrypting the payload content of the data file using at least one encryption key;

storing the at least one encryption key;

storing the encrypted payload content in the data container;

augmenting or reducing a size of the payload content of the data container such that the size of the payload content of the data container equals a size of the payload content of the data file; and

replacing the payload content of the data file with the payload content of the data container.

2. The method according to claim 1, wherein the distributed computing system is a cloud computing system.

3. The method according to claim 1, wherein evaluating the data file for determining the communication protocol comprises:

determining that the data file is encrypted; and

determining an encryption key used to encrypt the data file,

wherein the method further comprises;

responsive to determining the destination is the client and the source is the storage;

decrypting the data file using the determined encryption key; and

transmitting the data file to the client responsive to decrypting the data file.

4. The method according to claim 3, wherein in case the encryption key used to encrypt the data file is unknown the determining the encryption key comprises recovering during a predefined time period said encryption key using a Rainbow table.

5. The method according to claim 1, wherein the intercepting comprises:

sequentially intercepting data packets of the data file;

determining if the data file is complete;

in response to a determination that the data file is not complete, sending an acknowledgment message to the client for triggering further data transmission from the client.

6. The method according to claim 1, wherein the gateway device comprises a data structure of one or more entries comprising client category identifiers and corresponding encryption data, wherein replacing payload content of the data file with encrypted payload data comprises:

determining a client category identifier of the client;

reading the data structure using the client category identifier; and

determining the at least one encryption key based on the encryption data corresponding to the determined client category identifier.

7. The method according to claim 6, wherein the encryption data is indicative of an encryption strength in one or more levels of encryption.

8. The method according to claim 6, wherein determining the at least one encryption key comprises:

generating the at least one encryption key;

or

selecting the at least one encryption key from plurality of stored encryption keys.

9. The method according claim 1, wherein the plurality of analysis algorithms comprises an analysis algorithm for identifying sensitive data in the payload content of the data file by comparing the payload content of the data file with sensitive data pattern definitions stored in the distributed computing system.

10. The method according to claim 1, wherein the plurality of analysis algorithms further comprises a Reverse Spam Analysis algorithm.

11. The method according to claim 10, wherein analysis of the data file using the Reverse Spam Analysis algorithm comprises:

providing reference data for sensitive and non-sensitive data respectively;

processing the reference data by a statistical learning technique for generating weights to denote sensitive and non-sensitive data;

using the generated weights for determining whether the payload content of the data file comprises sensitive data.

12. The method according to claim 1, further comprising:

responsive to determining the destination is the client and the source is the storage;

determining whether the data file is encrypted in accordance with an encryption key of a plurality of stored encryption keys;

responsive to determining the data file is encrypted with a stored encryption key, decrypting the data file using the stored encryption key; and

transmitting the data file to the client in response to determining that the client satisfies a predefined authorization condition.

13. The method according to claim 12, wherein the distributed computing system comprises an access control list associated with the data file, the access control list comprising client identifiers of clients having access to the data file, wherein transmitting the data file to the client comprises:

identifying a client identifier of the client, wherein the predefined authorization condition is satisfied if the access control list comprises the client identifier.

14. The method according to claim 1, wherein analyzing the data file using each of the analysis algorithms for determining whether the data file comprises sensitive data comprises:

determining a respective set of results;

associating each result of the set of results with a number indicating whether the data file comprises sensitive or not sensitive data;

calculating a weighted sum of the numbers indicating whether the data file comprises sensitive data using the predefined weights;

comparing the weighted sum with a predetermined sensitivity threshold value.