Last update: December 16, 2021

Creating and sending private transactions

Create and send private transactions using:

All private transaction participants must be online for a private transaction to be successfully distributed. If any participants are offline when submitting the private transaction, the transaction is not attempted and you must resubmit the transaction.

The gas and gasPrice specified when sending a private transaction are used by the privacy marker transaction (PMT), not the private transaction itself.

Note

Private transactions either deploy contracts or call contract functions. Ether transfer transactions cannot be private.

`eea_sendRawTransaction`

eea_sendRawTransaction distributes the private transaction to the participating nodes, and signs and submits the PMT, as described in Private transaction processing.

Note

If sending concurrent transactions, you must use priv_distributeRawTransaction instead of eea_sendRawTransaction.

`priv_distributeRawTransaction`

Use priv_distributeRawTransaction instead of eea_sendRawTransaction when sending concurrent private transactions.

priv_distributeRawTransaction distributes the private transaction to the participating nodes but does not sign and submit the PMT. That is, it performs steps 1 to 5 of Private Transaction Processing.

If using priv_distributeRawTransaction instead of eea_sendRawTransaction, use the value returned by priv_distributeRawTransaction, which is the enclave key to the private transaction in Tessera, in the data field of a call to eth_sendRawTransaction. Use the value returned by priv_getPrivacyPrecompileAddress, which is the address of the privacy precompiled contract, in the to field of the call.

By using the public Ethereum transaction, eth_sendRawTransaction, you are signing and submitting the PMT yourself instead of having it signed by the Besu node, giving you greater control over the PMT.

Warning

If the PMT is not sent after distributing the private transaction, the distributed private transaction is not executed and the private states are not updated.

Example

Distribute private transaction using priv_distributeRawTransaction:

{
  "jsonrpc":"2.0",
  "method":"priv_distributeRawTransaction",
  "params":["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"],
  "id":1
}

Enclave key to the private transaction in Tessera returned by priv_distributeRawTransaction:

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0xfd0d90ab824574abc19c0776ca0210e764561d0ef6d621f2bbbea316eccfe56b"
}

Send the enclave key in the data field, and the privacy precompile address in the to field of eth_sendRawTransaction:

{
  "jsonrpc":"2.0",
  "method":"eth_sendRawTransaction",
  "params":[{
    "from": "0xfe3b557e8fb62b89f4916b721be55ceb828dbd73",
    "to": "0x000000000000000000000000000000000000007e",
    "data": "0xfd0d90ab824574abc19c0776ca0210e764561d0ef6d621f2bbbea316eccfe56b",
    "gas": "0x2E1800",
    "gasPrice": "0x9184e72a000"
  }],
  "id":1
}

EEA-compliant or Besu-extended privacy

To create an EEA-compliant private transaction, specify privateFor when creating the signed transaction passed as an input parameter to eea_sendRawTransaction.

To create a Besu-extended private transaction, specify a privacyGroupId when creating the signed transaction passed as an input parameter to eea_sendRawTransaction.

Unsigned and unencoded private transactions

The eea_sendRawTransaction parameter is a signed RLP-encoded private transaction. Shown below are examples of unsigned and unencoded private transactions to create a contract.

Unencoded and unsigned EEA-compliant private transaction

{
  "to": null,
  "from": "0xfe3b557e8fb62b89f4916b721be55ceb828dbd73",
  "gas": "0x7600",
  "gasPrice": "0x0",
  "data": "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",
  "nonce": "0x0",
  "privateFrom": "negmDcN2P4ODpqn/6WkJ02zT/0w0bjhGpkZ8UP6vARk=",
  "privateFor": ["g59BmTeJIn7HIcnq8VQWgyh/pDbvbt2eyP0Ii60aDDw=","6fg8q5rWMBoAT2oIiU3tYJbk4b7oAr7dxaaVY7TeM3U="],
  "restriction": "restricted"
}

Unencoded and unsigned Besu-extended private transaction

{
  "to": null,
  "from": "0xfe3b557e8fb62b89f4916b721be55ceb828dbd73",
  "gas": "0x7600",
  "gasPrice": "0x0",
  "data": "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",
  "nonce": "0x0",
  "privateFrom": "negmDcN2P4ODpqn/6WkJ02zT/0w0bjhGpkZ8UP6vARk=",
  "privacyGroupId": "kAbelwaVW7okoEn1+okO+AbA4Hhz/7DaCOWVQz9nx5M=",
  "restriction": "restricted"
}

Tip

The example directory in the web3js-quorum client library contains examples of signing and encoding private transactions.