Presigner

Multisig transaction presigner made easy <3

Setup

1. Install golang

2. Install Foundry

make install-foundry

3. Download Foundry dependencies

make deps

Usage

This tool is used to create and sign transactions for multisig safe calls.

The transactions are created and verified using solidity scripting by calling the actual safe contract functions. It stores state in a single self-contained JSON file.

Once the transaction is fully signed, the simulate command produces a oneliner shell script encoded in Base64 that can be easily stored in secret vaults for later use. The onliner has dependency only on cast (from Foundry).

File format

{
    "chain_id": "5",
    "created_at": "2023-11-06T14:53:30-08:00",
    "data": "0x1901c0d0e680d49115459ede72891964cf5adc2cf1930f57e7d8f7cf2408ed63d6ad81b0007322861e475d3f147da54ca8278d8f2850deaf5c736817f679a65332fc",
    "rpc_url": "https://ethereum-goerli.publicnode.com",
    "safe_addr": "0xb7b28ac0c0ffab4188826b14d02b17e8b444ed9e",
    "safe_nonce": "3",
    "script_name": "CallPause",
    "signatures": [
        {
            "signer": "0x1234567890123456789012345678901234567890",
            "signature": "1111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111"
        },
        {
            "signer": "0x1234567890123456789012345678901234567891",
            "signature": "2111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111"
        }
    ],
    "target_addr": "0x95B78e7A9f856161B8fE255Cf92C38d693aC6f5e"
}

Commands

nonce

Verifies the current nonce of a safe, example:

go run presigner.go \
    --safe-addr 0xb7b28ac0c0ffab4188826b14d02b17e8b444ed9e \
    nonce

create

Creates a new transaction to be signed, example:

go run presigner.go \
    --json-file tx/2023-11-06-goerli-pause-3.json \
    --chain 5 \
    --rpc-url https://ethereum-goerli.publicnode.com \
    --target-addr 0xfAF96f23026CA4863B6dcA30204aD5D2675738b8 \
    --safe-addr 0xb7b28ac0c0ffab4188826b14d02b17e8b444ed9e \
    --safe-nonce 3 \
    create

2023/11/06 13:12:32 saved: tx/2023-11-06-goerli-pause-3.json

Customizing the safe-nonce parameter it is possible to create transactions in advance.

sign

Signs a transaction previously created, example:

go run presigner.go \
    --json-file tx/2023-11-06-goerli-pause-3.json \
    --private-key 0000000000000000000000000000000000000000000000000000000000000000 \
    sign

2023/11/06 13:12:42 added signature for 0x1234567890123456789012345678901234567890

As new signatures are added, the transaction is updated and saved.

We use eip712signer to sign the transaction, which currently supports:

• private-key
• ledger
• mnemonic

verify

Verifies if a transaction previously created has valid signatures to be executed, example:

go run presigner.go \
    --json-file tx/2023-11-06-goerli-pause-3.json \
    verify

simulate

Simulate the transaction execution in a forked VM, example:

go run presigner.go \
    --json-file tx/2023-11-06-goerli-pause-3.json \
    simulate

If the simulation succeeds, it will also print a cheat sheet to execute the transaction in the network, i.e.:

- - 8< - -

EXECUTORKEY=********
go run presigner.go \
    --json-file tx/2023-11-06-goerli-pause-3.json \
    --private-key $EXECUTORKEY \
    execute

- - 8< - -

Or you can use the oneliner script encoded in base64, i.e.:

- - 8< - -
/bin/bash <(base64 -d -i tx/2023-11-06-goerli-pause-3.sh.b64) --rpc-url https://ethereum-goerli.publicnode.com
- - 8< - -

The onliner script is a single line shell script that uses cast to execute the transaction.

The arguments passed to the oneliner script are passed to cast send, so you can provide keys with --ledger, --private-key or --menmonics, override the --rpc-url and customize gas parameters at time of execution.

To see all options, just run cast send --help.

To double-check the contents of the oneliner script, you can use:

base64 -d -i tx/2023-11-07-goerli-pause-3.sh.b64

execute

Execute the transaction in the network, example:

go run presigner.go \
    --json-file tx/2023-11-06-goerli-pause-3.json \
    --private-key 0000000000000000000000000000000000000000000000000000000000000000 \
    execute

Note you need a private-key to execute the transaction, but it does not need to be a signer.

Safe error codes

From safe-contracts repo:

General init related

• GS000: Could not finish initialization
• GS001: Threshold needs to be defined
• GS002: A call to set up modules couldn't be executed because the destination account was not a contract

General gas/ execution related

• GS010: Not enough gas to execute Safe transaction
• GS011: Could not pay gas costs with ether
• GS012: Could not pay gas costs with token
• GS013: Safe transaction failed when gasPrice and safeTxGas were 0

General signature validation related

• GS020: Signatures data too short
• GS021: Invalid contract signature location: inside static part
• GS022: Invalid contract signature location: length not present
• GS023: Invalid contract signature location: data not complete
• GS024: Invalid contract signature provided
• GS025: Hash has not been approved
• GS026: Invalid owner provided

General auth related

• GS030: Only owners can approve a hash
• GS031: Method can only be called from this contract

Module management related

• GS100: Modules have already been initialized
• GS101: Invalid module address provided
• GS102: Module has already been added
• GS103: Invalid prevModule, module pair provided
• GS104: Method can only be called from an enabled module
• GS105: Invalid starting point for fetching paginated modules
• GS106: Invalid page size for fetching paginated modules

Owner management related

• GS200: Owners have already been set up
• GS201: Threshold cannot exceed owner count
• GS202: Threshold needs to be greater than 0
• GS203: Invalid owner address provided
• GS204: Address is already an owner
• GS205: Invalid prevOwner, owner pair provided

Guard management related

• GS300: Guard does not implement IERC165

Fallback handler related

• GS400: Fallback handler cannot be set to self