System and method for information protection

Patent metadata

Field	Value
Publication number	US-10715500-B2
Application number	US-201916708329-A
Country	US
Kind code	B2
Filing date	Dec 9, 2019
Priority date	Nov 27, 2018
Publication date	Jul 14, 2020
Grant date	Jul 14, 2020

Abstract

A computer-implemented method for information protection comprises: committing a transaction amount of a transaction with a first commitment scheme to obtain a transaction commitment value, committing a change of the transaction with a second commitment scheme to obtain a change commitment value, the first commitment scheme comprising a transaction blinding factor, and the second commitment scheme comprising a change blinding factor; encrypting a first combination of the change blinding factor and the change with a first key; transmitting the transaction blinding factor, the transaction amount, and the transaction commitment value to a recipient node associated with a recipient for the recipient node to verify the transaction; in response to that the recipient successfully verifies the transaction, obtaining an encrypted second combination of the transaction blinding factor and the transaction amount encrypted with a second key.

First claim

The invention claimed is:

1. A computer-implemented method for information protection, comprising:
obtaining a transaction blinding factor r t , a transaction amount t of a transaction, and a transaction commitment value T from a sender node associated with a sender of a transaction, wherein:
the transaction amount t is committed with a first commitment scheme to obtain the transaction commitment value T, the first commitment scheme comprising the transaction blinding factor r t ,
the transaction amount t is tapped from one or more assets A 1 , A 2 , . . . , A k of the sender of the transaction,
each of the assets is associated with (1) a Pedersen commitment based at least on a blinding factor r ak and a value of the each asset and (2) an encryption based at least on the blinding factor r ak and the value of the each asset, and
a change y is a difference between the transaction amount t and the tapped assets;

verifying the transaction based on the obtained transaction blinding factor r t , the obtained transaction amount t of a transaction, and the obtained transaction commitment value T;
in response to successfully verifying the transaction, encrypting a second combination of the transaction blinding factor r t and the transaction amount t with a second key KB;
generating a signature SIGB associated with the encrypted second combination and the transaction commitment value T; and
transmitting the encrypted second combination and the signature SIGB to the sender node for the sender node to verify the signature SIGB and to, in response to the sender node successfully verifying the signature SIGB, generate a signature SIGA associated with the assets A 1 , A 2 , . . . , A k , an encrypted first combination of a change blinding factor r y and the change y encrypted with a first key KA, the encrypted second combination, the transaction commitment value T, a change commitment value Y committing the change y with a second commitment scheme, and a difference between a sum of blinding factors corresponding to the assets A 1 , A 2 , . . . , A k and a sum of the transaction blinding factor r t and the change blinding factor r y .

2. The method of claim 1 , wherein:
verifying the transaction based on the obtained transaction blinding factor r t , the obtained transaction amount t of a transaction, and the obtained transaction commitment value T comprises verifying if the obtained transaction commitment value T is equal to a commitment value based on the first commitment scheme committing the obtained transaction amount t with the obtained transaction blinding factor r t .

3. The method of claim 1 , wherein transmitting the encrypted second combination and the signature SIGB to the sender node further comprises:
transmitting the encrypted second combination and the signature SIGB to the sender node for the sender node to generate a blockchain transaction for adding to a blockchain, the blockchain transaction comprising: the assets A 1 , A 2 , . . . , A k , the encrypted first combination, the encrypted second combination, the transaction commitment value T, the change commitment value Y, the difference between the sum of blinding factors corresponding to the assets A 1 , A 2 , . . . , A k and the sum of the transaction blinding factor r t and the change blinding factor r y , the signature SIGA, and the signature SIGB.

4. The method of claim 1 , wherein:
the first commitment scheme comprises a Pedersen commitment based at least on the transaction blinding factor r t and with the transaction amount t being a corresponding committed value.

5. Non-transitory computer-readable storage media storing instructions that, when executed by at least one processor, cause the at least one processor to perform operations comprising:
obtaining a transaction blinding factor r t , a transaction amount t of a transaction, and a transaction commitment value T from a sender node associated with a sender of a transaction, wherein:
the transaction amount t is committed with a first commitment scheme to obtain the transaction commitment value T, the first commitment scheme comprising the transaction blinding factor r t ,
the transaction amount t is tapped from one or more assets A 1 , A 2 , . . . , A k of the sender of the transaction,
each of the assets is associated with (1) a Pedersen commitment based at least on a blinding factor r ak and a value of the each asset and (2) an encryption based at least on the blinding factor r ak and the value of the each asset, and
a change y is a difference between the transaction amount t and the tapped assets;

verifying the transaction based on the obtained transaction blinding factor r t , the obtained transaction amount t of a transaction, and the obtained transaction commitment value T;
in response to successfully verifying the transaction, encrypting a second combination of the transaction blinding factor r t and the transaction amount t with a second key KB;
generating a signature SIGB associated with the encrypted second combination and the transaction commitment value T; and
transmitting the encrypted second combination and the signature SIGB to the sender node for the sender node to verify the signature SIGB and to, in response to the sender node successfully verifying the signature SIGB, generate a signature SIGA associated with the assets A 1 , A 2 , . . . , A k , an encrypted first combination of a change blinding factor r y , and the change y encrypted with a first key KA, the encrypted second combination, the transaction commitment value T, a change commitment value Y committing the change v with a second commitment scheme, and a difference between a sum of blinding factors corresponding to the assets A 1 , A 2 , . . . , A k and a sum of the transaction blinding factor r t and the change blinding factor r y .

6. The storage media of claim 5 , wherein:
verifying the transaction based on the obtained transaction blinding factor r t , the obtained transaction amount t of a transaction, and the obtained transaction commitment value T comprises verifying if the obtained transaction commitment value T is equal to a commitment value based on the first commitment scheme committing the obtained transaction amount t with the obtained transaction blinding factor r t .

7. The storage media of claim 5 , wherein transmitting the encrypted second combination and the signature SIGB to the sender node further comprises:
transmitting the encrypted second combination and the signature SIGB to the sender node for the sender node to generate a blockchain transaction for adding to a blockchain, the blockchain transaction comprising: the assets A 1 , A 2 , . . . , A k , the encrypted first combination, the encrypted second combination, the transaction commitment value T, the change commitment value Y, the difference between the sum of blinding factors corresponding to the assets A 1 , A 2 , . . . , A k and the sum of the transaction blinding factor r t and the change blinding factor r y , the signature SIGA, and the signature SIGB.

8. The storage media of claim 5 , wherein:
the first commitment scheme comprises a Pedersen commitment based at least on the transaction blinding factor r t and with the transaction amount t being a corresponding committed value.

9. A system for information protection, comprising at least one processor and non-transitory computer-readable storage media coupled to the at least one processor, the storage media storing instructions that, when executed by at least one processor, cause the system to perform operations comprising:
obtaining a transaction blinding factor r t , a transaction amount t of a transaction, and a transaction commitment value T from a sender node associate

Assignees

• Alibaba Group Holding Ltd

Inventors

• Ma Huanyu
• Zhang Wenbin
• Ma Baoli
• Liu Zheng
• Cui Jiahui

Classifications

• H04L9/50

  using hash chains, e.g. blockchains or hash trees · CPC title

• G06Q2220/00

  Business processing using cryptography · CPC title

• H04L63/0428 Primary

  wherein the data content is protected, e.g. by encrypting or encapsulating the payload · CPC title

• H04L9/3255

  using group based signatures, e.g. ring or threshold signatures · CPC title

• H04L9/3252

  using DSA or related signature schemes, e.g. elliptic based signatures, ElGamal or Schnorr schemes · CPC title