ConsenSys Diligence Audit Report from October 5, 2018
This repo represents the contracts that make up the Meridio Asset Token ecosystem.
For more information about Meridio, visit Meridio.co
This repo is setup to use Truffle, so you can run standard commands:
truffle test
truffle migrate
truffle compile
Other Commands that are available:
npm run coverage
- Generates the Solidity Test Coverage reportnpm run test
- Runs truffle test suitenpm run hint
- Generates solhint reportnpm run myth
- Recompiles contracts and runs Mythril for Truffle
Environment Variables:
INFURA_PROJECT_ID
- (Legacy) Infura ID for connecting to infura rinkeby nodeMNEMONIC_PHRASE
- mnemonic phrase to give access to the wallet for launching on Rinkeby
This is a copy of the Dai contract that Meridio uses in its test environments to mock interactions with Mainnet Dai.
This is a copy of the Airswap Exchange contract that Meridio uses for P2P swaps between AssetTokens and Dai.
This is a modified ERC20 that represents the core of the Meridio token ecosystem. It has modules on it to validate transfers and is used to track the tokens for each asset in the Meridio system. It will be launched as a Singleton and each Token in the system will be a proxy that references this implementation. When deploying the singleton, the deployer should ensure that the implementation gets initialized. The ProxyTokenFactory is recommended for launching new individual tokens as that will initialize them in the initial transaction. Key Modifications to ERC20 standard:
- Adding
canSend
checks before allowingtransfer
,transferFrom
,forceTransfer
functions to run - Adding
forceTranfer
function to allow the owner to move tokens from one address to another in compliance with thecanSend
parameters. - Allowing owner to
mint
/burn
to/from any address - Allow owner to
addModule
/removeModule
to control the parameters ofcanSend
Inheritance Chain:
This contract combines an upgradeability proxy with basic authorization control functionalities Source https://github.com/zeppelinos/labs/blob/master/upgradeability_using_unstructured_storage/contracts/OwnedUpgradeabilityProxy.sol Interface Reference: https://github.com/ethereum/EIPs/blob/master/EIPS/eip-897.md Implementation notes:
- constructors will not work, the proxied contract must be initialized after proxying. That is what the upgradeToAndCall function is for.
- if you do not inherit your version n-1 into version n, you will overwrite memory slots with the new contract.
- if you inherit version n-1 into version n, you will preserve memory slots including the _initialized flag.
- Therefore each new contract that needs to be initialized should have its own _initialized flag and function.
- ProxyOwner can change implementation reference and reassign ownership (of the proxy)
Inheritance Chain:
UpgradeabilityProxy
>Proxy
>ERCProxy
This singleton launches a new proxy contract and points it to the implementation it is given. It then assigns ownership of the Token (impl) and the Proxy to the msg.sender
Inheritance Chain:
Note: Imports OwnedUpgradeabilityProxy.sol
as ProxyToken
This TransferValidator contract reverts transfers if the to
address is true
in the blacklist mapping.
Permissions:
The owner
of the contract can add/remove addresses from the blacklist.
Inheritance Chain:
This TransferValidator contract reverts transfers if the transfer would cause there to be too many investors. InvestorCount
and InvestorCap
are tracked as state on this contract. There is one InvestorCount
per msg.sender
that interacts with this contract and a single InvestorCap
. (In the case of a token transfer msg.sender
is the token contract.)
Logic:
If to
has a balance of 0 and from
will not have a balance of 0 after the trade then increase investorCount
for msg.sender
.
If from
will have a balance of 0 and to
already has a balance of token, then decrease investorCount
for msg.sender
.
Report false
if a trade would cause investorCount
to be greater than investorCap
.
Permissions:
The owner
of the contract can manually update the investorCount
for any address and can set the InvestorCap
.
Inheritance Chain:
This TransferValidator contract reverts transfers if the transfer would cause there to be too few investors. InvestorCount
and InvestorMin
are tracked as state on this contract. There is one InvestorCount
per msg.sender
that interacts with this contract and a single InvestorMin
. (In the case of a token transfer msg.sender
is the token contract.)
Logic:
If to
has a balance of 0 and from
will not have a balance of 0 after the trade then increase investorCount
for msg.sender
.
If from
will have a balance of 0 and to
already has a balance of token, then decrease investorCount
for msg.sender
.
Report false
if a trade would cause investorCount
to be less than investorMin
.
Permissions:
The owner
of the contract can manually update the investorCount
for any address and can set the InvestorMin
.
Inheritance Chain:
This TransferValidator contract reverts transfers if the transfer would occur before the specified openingTime
(compared against block.timestamp
).
Permissions:
The owner
of the contract can manually update the openingTime
.
Inheritance Chain:
This TransferValidator contract reverts transfers if the transfer would increase the to
address's balance
above a maxAmount
.
Permissions:
The owner
of the contract can manually update the maxAmount
.
Inheritance Chain:
This TransferValidator contract reverts transfers if the validator is paused.
Permissions:
The owner
of the contract can pause/unpause the contract.
Inheritance Chain:
This TransferValidator contract reverts transfers if the from
address is true
in the blacklist mapping.
Permissions:
The owner
of the contract can add/remove addresses from the blacklist.
Inheritance Chain:
This TransferValidator contract reverts transfers if the from
address is false
in the whitelist mapping.
Permissions:
The owner
of the contract can add/remove addresses from the whitelist.
Inheritance Chain:
This TransferValidator contract reverts transfers if the to
address is false
in the whitelist mapping.
Permissions:
The owner
of the contract can add/remove addresses from the whitelist.
Inheritance Chain:
This is a singleton contract that allows anyone to send many ERC20 compliant token transfers of various amounts to various payees. The sender must have approved the contract to transferFrom
on its behalf beforehand.
This is a crowdsale contract based on openzeppelin contracts. It allows for the purchasing of AssetTokens with ETH via transferFrom
function. It has a conversion rate
and openingTime
/closingTime
. The Owner can update the Rate as needed to adjust for price fluxuations in ETH.
Inheritance Chain:
openzeppelin/AllowanceCrowdsale
openzeppelin/TimedCrowdsale
openzeppelin/TokenDestructible
openzeppelin/Pausable
This is a singleton contract that allows anyone to add key/value pairs to any “subject” smart contract address. The keys are meant to be simple identifiers, and the value is a string intended to be a link to HTTP or IPFS accessible data.
Inheritance Chain: