Zellic - Audit Reports

IBC transfer not according to spec

The data packet for an ICS20 transfer is defined as such:

interface FungibleTokenPacketData {
  denom: string
  amount: uint256
  sender: string
  receiver: string
  memo: string
}

However, the ICS20 transfer code is defined as such, failing if the packet_data is too large for a u128 due to overflow. This is something to be aware of, as a valid ICS20 transfer may fail.

#[allow(clippy::too_many_lines)]
async fn execute_ics20_transfer<S: StateWriteExt>(
    state: &mut S,
    data: &[u8],
    source_port: &PortId,
    source_channel: &ChannelId,
    dest_port: &PortId,
    dest_channel: &ChannelId,
    is_refund: bool,
) -> Result<()> {
    let packet_data: FungibleTokenPacketData =
        serde_json::from_slice(data).context("failed to decode FungibleTokenPacketData")?;
    let packet_amount: u128 = packet_data
        .amount
        .parse()
        .context("failed to parse packet data amount to u128")?;
    ...
}