A method for an invocation of a smart contract, the method comprising: receiving a target transaction used to initiate the invocation of the smart contract based on a blockchain, wherein the target transaction comprises invocation data, and wherein at least a part of the invocation data comprises a data digest of target data stored in a third-party storage system interconnected with the blockchain; querying the target data corresponding to the data digest from the third-party storage system; receiving a query result from the third-party storage system, wherein the query result comprises encrypted target data and key metadata corresponding to a key; obtaining the key used to decrypt the encrypted target data and decrypting the encrypted target data based on the key, including: sending the encrypted target data and the key metadata to a third-party decryption system interconnected with the blockchain; obtaining, by the third-party decryption system, the key corresponding to the key metadata based on a mapping relationship between the key and the key metadata, and decrypting the encrypted target data based on the key to provide decrypted target data; and receiving the decrypted target data from the third-party decryption system; performing content verification on the decrypted target data; in response to determining that the content verification on the decrypted target data succeeds, invoking the smart contract to perform smart contract computation on the invocation data in the target transaction; and storing a computation result in a distributed database of the blockchain after the smart contract computation is completed, wherein the blockchain is a first member blockchain in a consortium blockchain that comprises several member blockchains, wherein the third-party storage system is a second member blockchain in the consortium blockchain and has a cross-chain data reference relationship with the blockchain, and wherein the third-party decryption system is a third member blockchain in the consortium blockchain. receiving a target transaction used to initiate the invocation of the smart contract based on a blockchain, wherein the target transaction comprises invocation data, and wherein at least a part of the invocation data comprises a data digest of target data stored in a third-party storage system interconnected with the blockchain; querying the target data corresponding to the data digest from the third-party storage system; receiving a query result from the third-party storage system, wherein the query result comprises encrypted target data and key metadata corresponding to a key; obtaining the key used to decrypt the encrypted target data and decrypting the encrypted target data based on the key, including: sending the encrypted target data and the key metadata to a third-party decryption system interconnected with the blockchain; obtaining, by the third-party decryption system, the key corresponding to the key metadata based on a mapping relationship between the key and the key metadata, and decrypting the encrypted target data based on the key to provide decrypted target data; and receiving the decrypted target data from the third-party decryption system; performing content verification on the decrypted target data; sending the encrypted target data and the key metadata to a third-party decryption system interconnected with the blockchain; obtaining, by the third-party decryption system, the key corresponding to the key metadata based on a mapping relationship between the key and the key metadata, and decrypting the encrypted target data based on the key to provide decrypted target data; and receiving the decrypted target data from the third-party decryption system; performing content verification on the decrypted target data; in response to determining that the content verification on the decrypted target data succeeds, invoking the smart contract to perform smart contract computation on the invocation data in the target transaction; and storing a computation result in a distributed database of the blockchain after the smart contract computation is completed, wherein the blockchain is a first member blockchain in a consortium blockchain that comprises several member blockchains, wherein the third-party storage system is a second member blockchain in the consortium blockchain and has a cross-chain data reference relationship with the blockchain, and wherein the third-party decryption system is a third member blockchain in the consortium blockchain.