A computer-implemented method for information protection, comprising: generating, by a sender node associated with a sender of a transaction, a transaction commitment value T by committing a transaction amount t of the transaction with a commitment scheme based at least on a transaction blinding factor r_t, wherein the transaction comprises transferring the transaction amount t from an address associated with a public key PK_1_A of the sender to an address associated with a public key PK_1_B of a recipient of the transaction, and the transaction amount t is from one or more assets of the sender recorded in a blockchain; encrypting, by the sender node, a first combination of the transaction blinding factor r_t and the transaction amount t with a public key PK_2_B of the recipient of the transaction, wherein the public key PK_2_B is different from the public key PK_1_B; transmitting, by the sender node and via an off-blockchain channel, the transaction commitment value T and the encrypted first combination to a recipient node associated with the recipient for the recipient node to verify the transaction; receiving, by the sender node from the recipient node, a recipient signature SIGB generated by the recipient node signing the transaction with a private key SK_1_B of the recipient in response to successfully verifying the transaction, wherein the public key PK_1_B and the private key SK_1_B are a public-private key pair of the recipient; generating, by the sender node, a sender signature SIGA by signing the transaction with a private key SK_1_A of the sender, wherein the public key PK_1_A and the private key SK_1_A are a public-private key pair of the sender; generating, by the sender node, an updated version of the transaction, the updated version of the transaction comprising the encrypted first combination, the transaction commitment value T, the sender signature SIGA, and the recipient signature SIGB; and submitting, by the sender node, the updated version of the transaction to one or more blockchain nodes of the blockchain. generating, by a sender node associated with a sender of a transaction, a transaction commitment value T by committing a transaction amount t of the transaction with a commitment scheme based at least on a transaction blinding factor r_t, wherein the transaction comprises transferring the transaction amount t from an address associated with a public key PK_1_A of the sender to an address associated with a public key PK_1_B of a recipient of the transaction, and the transaction amount t is from one or more assets of the sender recorded in a blockchain; encrypting, by the sender node, a first combination of the transaction blinding factor r_t and the transaction amount t with a public key PK_2_B of the recipient of the transaction, wherein the public key PK_2_B is different from the public key PK_1_B; transmitting, by the sender node and via an off-blockchain channel, the transaction commitment value T and the encrypted first combination to a recipient node associated with the recipient for the recipient node to verify the transaction; receiving, by the sender node from the recipient node, a recipient signature SIGB generated by the recipient node signing the transaction with a private key SK_1_B of the recipient in response to successfully verifying the transaction, wherein the public key PK_1_B and the private key SK_1_B are a public-private key pair of the recipient; generating, by the sender node, a sender signature SIGA by signing the transaction with a private key SK_1_A of the sender, wherein the public key PK_1_A and the private key SK_1_A are a public-private key pair of the sender; generating, by the sender node, an updated version of the transaction, the updated version of the transaction comprising the encrypted first combination, the transaction commitment value T, the sender signature SIGA, and the recipient signature SIGB; and submitting, by the sender node, the updated version of the transaction to one or more blockchain nodes of the blockchain.