feat: multichain ocr3 contract transmitter

contracts/scripts/native_solc_compile_all_shared

@@ -32,3 +32,4 @@ compileContract shared/token/ERC677/BurnMintERC677.sol
 compileContract shared/token/ERC677/LinkToken.sol
 compileContract shared/mocks/WERC20Mock.sol
 compileContract vendor/openzeppelin-solidity/v4.8.3/contracts/token/ERC20/ERC20.sol
+compileContract shared/ocr3/NoOpOCR3.sol

contracts/src/v0.8/shared/ocr3/NoOpOCR3.sol

@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: BUSL-1.1
+pragma solidity ^0.8.0;
+
+import {OCR3Base} from "./OCR3Base.sol";
+
+// NoOpOCR3 is a mock implementation of the OCR3Base contract that does nothing
+// This is so that we can generate gethwrappers for the contract and use the OCR3 ABI in
+// Go code.
+contract NoOpOCR3 is OCR3Base {
+  // solhint-disable-next-line chainlink-solidity/all-caps-constant-storage-variables
+  string public constant override typeAndVersion = "NoOpOCR3 1.0.0";
+
+  constructor() OCR3Base() {}
+
+  function _report(bytes calldata report, uint64 sequenceNumber) internal override {
+    // do nothing
+  }
+}

contracts/src/v0.8/shared/ocr3/OCR3Abstract.sol

@@ -0,0 +1,122 @@
+// SPDX-License-Identifier: BUSL-1.1
+pragma solidity ^0.8.0;
+
+import {ITypeAndVersion} from "../../shared/interfaces/ITypeAndVersion.sol";
+
+abstract contract OCR3Abstract is ITypeAndVersion {
+  // Maximum number of oracles the offchain reporting protocol is designed for
+  uint256 internal constant MAX_NUM_ORACLES = 31;
+
+  /// @notice triggers a new run of the offchain reporting protocol
+  /// @param previousConfigBlockNumber block in which the previous config was set, to simplify historic analysis
+  /// @param configDigest configDigest of this configuration
+  /// @param configCount ordinal number of this config setting among all config settings over the life of this contract
+  /// @param signers ith element is address ith oracle uses to sign a report
+  /// @param transmitters ith element is address ith oracle uses to transmit a report via the transmit method
+  /// @param f maximum number of faulty/dishonest oracles the protocol can tolerate while still working correctly
+  /// @param onchainConfig serialized configuration used by the contract (and possibly oracles)
+  /// @param offchainConfigVersion version of the serialization format used for "offchainConfig" parameter
+  /// @param offchainConfig serialized configuration used by the oracles exclusively and only passed through the contract
+  event ConfigSet(
+    uint32 previousConfigBlockNumber,
+    bytes32 configDigest,
+    uint64 configCount,
+    address[] signers,
+    address[] transmitters,
+    uint8 f,
+    bytes onchainConfig,
+    uint64 offchainConfigVersion,
+    bytes offchainConfig
+  );
+
+  /// @notice sets offchain reporting protocol configuration incl. participating oracles
+  /// @param signers addresses with which oracles sign the reports
+  /// @param transmitters addresses oracles use to transmit the reports
+  /// @param f number of faulty oracles the system can tolerate
+  /// @param onchainConfig serialized configuration used by the contract (and possibly oracles)
+  /// @param offchainConfigVersion version number for offchainEncoding schema
+  /// @param offchainConfig serialized configuration used by the oracles exclusively and only passed through the contract
+  function setOCR3Config(
+    address[] memory signers,
+    address[] memory transmitters,
+    uint8 f,
+    bytes memory onchainConfig,
+    uint64 offchainConfigVersion,
+    bytes memory offchainConfig
+  ) external virtual;
+
+  /// @notice information about current offchain reporting protocol configuration
+  /// @return configCount ordinal number of current config, out of all configs applied to this contract so far
+  /// @return blockNumber block at which this config was set
+  /// @return configDigest domain-separation tag for current config (see _configDigestFromConfigData)
+  function latestConfigDetails()
+    external
+    view
+    virtual
+    returns (uint32 configCount, uint32 blockNumber, bytes32 configDigest);
+
+  function _configDigestFromConfigData(
+    uint256 chainId,
+    address contractAddress,
+    uint64 configCount,
+    address[] memory signers,
+    address[] memory transmitters,
+    uint8 f,
+    bytes memory onchainConfig,
+    uint64 offchainConfigVersion,
+    bytes memory offchainConfig
+  ) internal pure returns (bytes32) {
+    uint256 h = uint256(
+      keccak256(
+        abi.encode(
+          chainId,
+          contractAddress,
+          configCount,
+          signers,
+          transmitters,
+          f,
+          onchainConfig,
+          offchainConfigVersion,
+          offchainConfig
+        )
+      )
+    );
+    uint256 prefixMask = type(uint256).max << (256 - 16); // 0xFFFF00..00
+    uint256 prefix = 0x0001 << (256 - 16); // 0x000100..00
+    return bytes32((prefix & prefixMask) | (h & ~prefixMask));
+  }
+
+  /// @notice optionally emitted to indicate the latest configDigest and sequence number
+  /// for which a report was successfully transmitted. Alternatively, the contract may
+  /// use latestConfigDigestAndEpoch with scanLogs set to false.
+  event Transmitted(bytes32 configDigest, uint64 sequenceNumber);
+
+  /// @notice optionally returns the latest configDigest and sequence number for which
+  /// a report was successfully transmitted. Alternatively, the contract may return
+  /// scanLogs set to true and use Transmitted events to provide this information
+  /// to offchain watchers.
+  /// @return scanLogs indicates whether to rely on the configDigest and sequence number
+  /// returned or whether to scan logs for the Transmitted event instead.
+  /// @return configDigest
+  /// @return sequenceNumber
+  function latestConfigDigestAndEpoch()
+    external
+    view
+    virtual
+    returns (bool scanLogs, bytes32 configDigest, uint64 sequenceNumber);
+
+  /// @notice transmit is called to post a new report to the contract
+  /// @param report serialized report, which the signatures are signing.
+  /// @param rs ith element is the R components of the ith signature on report. Must have at most MAX_NUM_ORACLES entries
+  /// @param ss ith element is the S components of the ith signature on report. Must have at most MAX_NUM_ORACLES entries
+  /// @param rawVs ith element is the the V component of the ith signature
+  function transmit(
+    // NOTE: If these parameters are changed, expectedMsgDataLength and/or
+    // TRANSMIT_MSGDATA_CONSTANT_LENGTH_COMPONENT need to be changed accordingly
+    bytes32[3] calldata reportContext,
+    bytes calldata report,
+    bytes32[] calldata rs,
+    bytes32[] calldata ss,
+    bytes32 rawVs // signatures
+  ) external virtual;
+}