signer/core: handle gnosis safe problem with missing chain id

[holiman]

This PR adds a check that the safetxhash that we sign corresponds to the one that is expected by the input. This PR also adds a case which is currently failing.

The current code calculates the safeTxHash for a certain json message differently than what is expected by the online safe tx machinery.

cc @rmeissner could you please help me figure out the difference here?

json:

{
  "safe": "0x899FcB1437DE65DC6315f5a69C017dd3F2837557",
  "to": "0x899FcB1437DE65DC6315f5a69C017dd3F2837557",
  "value": "0",
  "data": "0x0d582f13000000000000000000000000d3ed2b8756b942c98c851722f3bd507a17b4745f0000000000000000000000000000000000000000000000000000000000000005",
  "operation": 0,
  "gasToken": "0x0000000000000000000000000000000000000000",
  "safeTxGas": 0,
  "baseGas": 0,
  "gasPrice": "0",
  "refundReceiver": "0x0000000000000000000000000000000000000000",
  "nonce": 0,
  "executionDate": null,
  "submissionDate": "2022-02-23T14:09:00.018475Z",
  "modified": "2022-12-01T15:52:21.214357Z",
  "blockNumber": null,
  "transactionHash": null,
  "safeTxHash": "0x6f0f5cffee69087c9d2471e477a63cab2ae171cf433e754315d558d8836274f4",
  "executor": null,
  "isExecuted": false,
  "isSuccessful": null,
  "ethGasPrice": null,
  "maxFeePerGas": null,
  "maxPriorityFeePerGas": null,
  "gasUsed": null,
  "fee": null,
  "origin": "https://gnosis-safe.io",
  "dataDecoded": {
    "method": "addOwnerWithThreshold",
    "parameters": [
      {
        "name": "owner",
        "type": "address",
        "value": "0xD3Ed2b8756b942c98c851722F3bd507a17B4745F"
      },
      {
        "name": "_threshold",
        "type": "uint256",
        "value": "5"
      }
    ]
  },
  "confirmationsRequired": 4,
  "confirmations": [
    {
      "owner": "0x30B714E065B879F5c042A75Bb40a220A0BE27966",
      "submissionDate": "2022-03-01T14:56:22Z",
      "transactionHash": "0x6d0a9c83ac7578ef3be1f2afce089fb83b619583dfa779b82f4422fd64ff3ee9",
      "signature": "0x00000000000000000000000030b714e065b879f5c042a75bb40a220a0be27966000000000000000000000000000000000000000000000000000000000000000001",
      "signatureType": "APPROVED_HASH"
    },
    {
      "owner": "0x8300dFEa25Da0eb744fC0D98c23283F86AB8c10C",
      "submissionDate": "2022-12-01T15:52:21.214357Z",
      "transactionHash": null,
      "signature": "0xbce73de4cc6ee208e933a93c794dcb8ba1810f9848d1eec416b7be4dae9854c07dbf1720e60bbd310d2159197a380c941cfdb55b3ce58f9dd69efd395d7bef881b",
      "signatureType": "EOA"
    }
  ],
  "trusted": true,
  "signatures": null
}

Resulting preimage before keccak:

0x190119994026f194e6a8a9be0983c8c7fc49d8f1aa03b638577e35c4be0d082145c681d1e7162ad6fcb59199bcacdd11e8228484abcd2f5fde35a4b9be40e668bf24

Resulting hash:

0x6e6a5ede66d5838ec141746b6544a0140416bff184faff17cf62cab97f11f5ae

But the expectation is

  "safeTxHash": "0x6f0f5cffee69087c9d2471e477a63cab2ae171cf433e754315d558d8836274f4",

[mmv08]

@holiman code from the gnosis_safe.go signer

	var domainType = []apitypes.Type{{Name: "verifyingContract", Type: "address"}}
	if tx.ChainId != nil {
		domainType = append([]apitypes.Type{{Name: "chainId", Type: "uint256"}}, domainType[0])
	}

Relevant PR: #24231

Perhaps I should've added a comment there. So the safe you're using is version 1.3.0, which also factors in the chainId for the transaction hash. The JSON payload is missing the chainId parameter and therefore the function produces a mismatching hash.

[holiman]

The JSON payload is missing the chainId parameter and therefore the function produces a mismatching hash.

But why is that missing? It is coming directly from curl -X GET "https://safe-transaction-mainnet.safe.global/api/v1/safes/0x899FcB1437DE65DC6315f5a69C017dd3F2837557/multisig-transactions/?executed=false" -H "accept: application/json" -H "X-CSRFToken: oBRAVXzXeIzq0vfzp8bWjdPhZBTD25rj5vFzVKIYUZ4HwCJlXCuOWDJ7Vh333STp" | jq ".results[0]" .

[mmv08]

The JSON payload is missing the chainId parameter and therefore the function produces a mismatching hash.

But why is that missing? It is coming directly from curl -X GET "https://safe-transaction-mainnet.safe.global/api/v1/safes/0x899FcB1437DE65DC6315f5a69C017dd3F2837557/multisig-transactions/?executed=false" -H "accept: application/json" -H "X-CSRFToken: oBRAVXzXeIzq0vfzp8bWjdPhZBTD25rj5vFzVKIYUZ4HwCJlXCuOWDJ7Vh333STp" | jq ".results[0]" .

I think I've misphrased that, the payload is not missing it. Our services simply do not return it because we have a separate service per chain.

[karalabe]

SGTM