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Centrifuge-Ethereum Bridge

The CFG token can be bridged 1:1 to Ethereum. Read the guide here for instructions on how to bridge CFG.

Token Supply​

The bridge supply can be audited by comparing the number of tokens stored on the Centrifuge Chain bridge account with the ERC20 token supply of wCFG on Ethereum.

  • Centrifuge Chain (CFG): 4dpEcgqFp8UL6eA3b7hhtdj7qftHRZE7g1uadHyuw1WSNSgH
  • Ethereum (wCFG): 0xc221b7e65ffc80de234bbb6667abdd46593d34f0

Relayer Threshold​

You can submit an RPC call to a full node and query chainBridge.relayerThreshold. This will give you the number of confirmations needed on the Centrifuge Chain to trigger a transfer.

On Ethereum, you can query the Chainbridge public method _relayerThreshold()(uint8):

seth call 0xFe50BA7241b635Eda23a32875c383A34E8a3596c '_relayerThreshold()(uint8)'

Install ChainBridge Client tool​

export CB_DEPLOY=${CB_DEPLOY:-v1.0.0}
export CB_SOL_COMMIT=${CB_SOL_COMMIT:-v1.0.0}

cd $PARENT_DIR
git clone https://github.com/ChainSafe/chainbridge-deploy.git
cd $PARENT_DIR/chainbridge-deploy
git checkout $CB_CB_DEPLOY

BRIDGE_DEPLOYMENT_DIR=$PARENT_DIR/chainbridge-deploy/cb-sol-cli
cd $BRIDGE_DEPLOYMENT_DIR
GIT_COMMIT=$CB_SOL_COMMIT make install

Script Dependencies​

Install subkey [Optional]​

In the bash snippet below, we use subkey to convert the SS58 address into its public key representation, required by the deposit operation.

Follow instructions here: https://github.com/paritytech/substrate/tree/master/bin/utils/subkey

Or run the docker image: https://hub.docker.com/r/parity/subkey

Install Jq [Optional]​

In the bash snippet below, we use jq to parse a JSON output. You can choose to omit that and paste the address manually. Otherwise, follow instructions here to install in your distribution: https://stedolan.github.io/jq/.

Set environment variables​

Please submit a ticket on Discord for contract addresses.

export ETH_RPC_URL="YOUR_ETH_CLIENT_URL"
export ETH_PRIVATE_KEY="YOUR_PRIVATE_KEY"
export ETH_GAS_LIMIT=300000
export BRIDGE_ERC20_RESOURCE_ID="0x00000000000000000000000000000009e974040e705c10fb4de576d6cc261900"

Amber (Kovan) Config:

export ERC20_ADDRESS="AMBER_ERC20_CONTRACT"
export BRIDGE_ADDRESS="AMBER_BRIDGE_CONTRACT"
export BRIDGE_ERC20_HANDLER="AMBER_ERC20_HANDLER"
export ETH_GAS_PRICE=10000000000

Mainnet Config:

export ERC20_ADDRESS="MAINNET_ERC20_CONTRACT"
export BRIDGE_ADDRESS="MAINNET_BRIDGE_CONTRACT"
export BRIDGE_ERC20_HANDLER="MAINNET_ERC20_HANDLER"
export ETH_GAS_PRICE=40000000000

Substrate Native to ERC20 Ethereum​

In the substrate UI, select the Extrinsics tab and call palletBridge.transferNative with these parameters:

  • Amount: 1000000000000000000 (= 1 CFG)
  • Recipient: YOUR_ETH_TARGET_ACCOUNT
  • Dest Id: 0

Depending on environment and network state, this may take some time.

You can query the recipients balance on Ethereum:

cb-sol-cli --url $ETH_RPC_URL  erc20 balance --address YOUR_ETH_TARGET_ACCOUNT --erc20Address $ERC20_ADDRESS

ERC20 to Substrate Native​

Approve ERC20 Handler to move tokens on your behalf:

cb-sol-cli --gasLimit $ETH_GAS_LIMIT --gasPrice $ETH_GAS_PRICE --privateKey $ETH_PRIVATE_KEY --url $ETH_RPC_URL erc20 approve --amount 1000000000000000000 --recipient $BRIDGE_ERC20_HANDLER --erc20Address $ERC20_ADDRESS

Trigger Deposit against target chain and address:

TARGET_SUBSTRATE_ADDR="YOUR_SUBSTRATE_SS58_ADDRESS"
TARGET_PUBLICKEY=`subkey inspect --output-type json $TARGET_SUBSTRATE_ADDR | jq  -r '.publicKey'`

cb-sol-cli --gasLimit $ETH_GAS_LIMIT --gasPrice $ETH_GAS_PRICE --privateKey $ETH_PRIVATE_KEY --url $ETH_RPC_URL erc20 deposit --amount 1000000000000000000 --dest 1 --recipient $TARGET_PUBLICKEY --resourceId $BRIDGE_ERC20_RESOURCE_ID --bridge $BRIDGE_ADDRESS