Merge pull request #107 from poanetwork/develop

Merging the develop branch containing the ERC-TO-NATIVE mode to the master branch

.dockerignore

@@ -0,0 +1,9 @@
+node_modules
+deploy/node_modules
+.git
+.dockerignore
+deploy/.env
+docker-compose.yml
+Dockerfile
+*.log
+flats

Dockerfile

@@ -0,0 +1,17 @@
+FROM node:8
+
+WORKDIR /contracts
+
+COPY package.json .
+COPY package-lock.json .
+RUN npm install
+
+COPY ./deploy/package.json ./deploy/
+COPY ./deploy/package-lock.json ./deploy/
+RUN cd ./deploy; npm install; cd ..
+
+COPY . .
+RUN npm run compile
+RUN bash flatten.sh
+
+ENV PATH="/contracts/:${PATH}"

GAS_CONSUMPTION.md

@@ -0,0 +1,174 @@
+## Gas Consumption
+
+### `NATIVE-TO-ERC` Bridge Mode
+
+#### Deployment
+##### Home
+ Contract | Method | Min | Max | Avg
+----  | ---- | ---- | ---- | ----
+EternalStorageProxy|deployment|378510|378510|378510
+BridgeValidators|deployment|1144207|1144207|1144207
+EternalStorageProxy|upgradeTo|35871|30924|30913
+BridgeValidators|initialize|187738|280847|253949
+EternalStorageProxy|transferProxyOwnership|30653|30653|30653
+EternalStorageProxy|deployment|378510|378510|378510
+HomeBridgeNativeToErc|deployment|3327263|3327263|3327263
+EternalStorageProxy|upgradeTo|35871|30924|30913
+HomeBridgeNativeToErc|initialize|190051|190947|190755
+EternalStorageProxy|transferProxyOwnership|30653|30653|30653
+Total| |5739327|5823438|5796326
+
+##### Foreign
+ Contract | Method | Min | Max | Avg
+----  | ---- | ---- | ---- | ----
+ERC677BridgeToken|deployment|1498202|1499226|1498829
+EternalStorageProxy|deployment|378510|378510|378510
+BridgeValidators|deployment|1144207|1144207|1144207
+EternalStorageProxy|upgradeTo|35871|30924|30913
+BridgeValidators|initialize|187738|280847|253949
+EternalStorageProxy|transferProxyOwnership|30653|30653|30653
+EternalStorageProxy|deployment|378510|378510|378510
+ForeignBridgeNativeToErc|deployment|2768705|2768705|2768705
+EternalStorageProxy|upgradeTo|35871|30924|30913
+ForeignBridgeNativeToErc|initialize|213493|213557|213549
+ERC677BridgeToken|setBridgeContract|29432|44432|39432
+ERC677BridgeToken|transferOwnership|30860|30924|30913
+EternalStorageProxy|transferProxyOwnership|30653|30653|30653
+Total| |6762705|6862072|6829736
+
+#### Usage
+
+##### Validators
+
+ Contract | Method | Min | Max | Avg
+----  | ---- | ---- | ---- | ----
+To sign at the Home (each validator)|
+HomeBridgeNativeToErc|submitSignature|159362|275135|220127
+To relay signatures from the Home to the Foreign (one validator)|
+ForeignBridgeNativeToErc|executeSignatures|89201|146127|120917
+To sign and relay from the Foreign to the Home (each validator)|
+HomeBridgeNativeToErc|executeAffirmation|64314|107669|83596
+
+##### Users
+
+ Contract | Method | Min | Max | Avg
+----  | ---- | ---- | ---- | ----
+To request transfer from the Home to the Foreign|
+HomeBridgeNativeToErc|fallback|46982|46982|46982
+To request transfer from the Foreign to the Home|
+ERC677BridgeToken|transferAndCall|58370|166206|92399  
+
+
+### `ERC-TO-ERC` Bridge Mode
+
+#### Deployment
+##### Home
+ Contract | Method | Min | Max | Avg
+----  | ---- | ---- | ---- | ----
+EternalStorageProxy|deployment|378510|378510|378510
+BridgeValidators|deployment|1144207|1144207|1144207
+EternalStorageProxy|upgradeTo|35871|30924|30913
+BridgeValidators|initialize|187738|280847|253949
+EternalStorageProxy|transferProxyOwnership|30653|30653|30653
+EternalStorageProxy|deployment|378510|378510|378510
+HomeBridgeErcToErc|deployment|3528509|3528509|3528509
+EternalStorageProxy|upgradeTo|35871|30924|30913
+ERC677BridgeToken|deployment|1498202|1499226|1498829
+ERC677BridgeToken|setBridgeContract|29432|44432|39432
+ERC677BridgeToken|transferOwnership|30860|30924|30913
+HomeBridgeErcToErc|initialize|212299|213195|213003
+EternalStorageProxy|transferProxyOwnership|30653|30653|30653
+Total| |7521315|7621514|7588994
+
+##### Foreign
+ Contract | Method | Min | Max | Avg
+----  | ---- | ---- | ---- | ----
+EternalStorageProxy|deployment|378510|378510|378510
+BridgeValidators|deployment|1144207|1144207|1144207
+EternalStorageProxy|upgradeTo|35871|30924|30913
+BridgeValidators|initialize|187738|280847|253949
+EternalStorageProxy|transferProxyOwnership|30653|30653|30653
+EternalStorageProxy|deployment|378510|378510|378510
+ForeignBridgeErcToErc|deployment|2449436|2449436|2449436
+EternalStorageProxy|upgradeTo|35871|30924|30913
+ForeignBridgeErcToErc|initialize|150614|150614|150614
+EternalStorageProxy|transferProxyOwnership|30653|30653|30653
+Total| |4822063|4905278|4878358
+
+#### Usage
+
+##### Validators
+
+ Contract | Method | Min | Max | Avg
+----  | ---- | ---- | ---- | ----
+To sign at the Home (each validator)|
+HomeBridgeErcToErc|submitSignature|159386|275159|220171
+To relay signatures from the Home to the Foreign (one validator)|
+ForeignBridgeErcToErc|executeSignatures|73779|115769|93027
+To sign and relay from the Foreign to the Home (each validator)|
+HomeBridgeErcToErc|executeAffirmation|79336|134607|108215
+
+##### Users
+
+ Contract | Method | Min | Max | Avg
+----  | ---- | ---- | ---- | ----
+To request transfer from the Home to the Foreign|
+ERC677BridgeToken|transferAndCall|58370|166206|92399
+To request transfer from the Foreign to the Home|
+ERC677BridgeToken|transfer|37691|86589|55000  
+
+
+### `ERC-TO-NATIVE` Bridge Mode
+
+#### Deployment
+##### Home
+ Contract | Method | Min | Max | Avg
+----  | ---- | ---- | ---- | ----
+EternalStorageProxy|deployment|378510|378510|378510
+BridgeValidators|deployment|1144207|1144207|1144207
+EternalStorageProxy|upgradeTo|35871|30924|30913
+BridgeValidators|initialize|187738|280847|253949
+EternalStorageProxy|transferProxyOwnership|30653|30653|30653
+EternalStorageProxy|deployment|378510|378510|378510
+HomeBridgeErcToNative|deployment|3757420|3757420|3757420
+EternalStorageProxy|upgradeTo|35871|30924|30913
+HomeBridgeErcToNative|initialize|196910|213930|210795
+EternalStorageProxy|transferProxyOwnership|30653|30653|30653
+Total| |6176343|6276578|6246523
+
+##### Foreign
+ Contract | Method | Min | Max | Avg
+----  | ---- | ---- | ---- | ----
+EternalStorageProxy|deployment|378510|378510|378510
+BridgeValidators|deployment|1144207|1144207|1144207
+EternalStorageProxy|upgradeTo|35871|30924|30913
+BridgeValidators|initialize|187738|280847|253949
+EternalStorageProxy|transferProxyOwnership|30653|30653|30653
+EternalStorageProxy|deployment|378510|378510|378510
+ForeignBridgeErcToNative|deployment|2449564|2449564|2449564
+EternalStorageProxy|upgradeTo|35871|30924|30913
+ForeignBridgeErcToNative|initialize|150614|150614|150614
+EternalStorageProxy|transferProxyOwnership|30653|30653|30653
+Total| |
+
+#### Usage
+
+##### Validators
+
+ Contract | Method | Min | Max | Avg
+----  | ---- | ---- | ---- | ----
+To sign at the Home (each validator)|
+HomeBridgeErcToNative|submitSignature|159428|275201|220206
+To relay signatures from the Home to the Foreign (one validator)|
+ForeignBridgeErcToNative|executeSignatures|73779|115769|92985
+To sign and relay from the Foreign to the Home (each validator)|
+HomeBridgeErcToNative|executeAffirmation|64380|140744|97562
+
+##### Users
+
+ Contract | Method | Min | Max | Avg
+----  | ---- | ---- | ---- | ----
+To request transfer from the Home to the Foreign|
+HomeBridgeErcToNative|fallback|80174|80174|80174
+To request transfer from the Foreign to the Home|
+ERC677BridgeToken|transfer|37691|86589|55000

README.md

@@ -25,6 +25,7 @@ The POA Bridge allows users to transfer assets between two chains in the Ethereu
 Currently, the contracts support two types of relay operations:
 * Tokenize the native coin in one blockchain network (Home) into an ERC20 token in another network (Foreign).
 * Swap a token presented by an existing ERC20 contract in a Foreign network into an ERC20 token in the Home network, where one pair of bridge contracts corresponds to one pair of ERC20 tokens.
+* to mint new native coins in Home blockchain network from a token presented by an existing ERC20 contract in a Foreign network.
 
 
 ### Components
@@ -35,6 +36,7 @@ The POA bridge contracts consist of several components:
 * Depending on the type of relay operations the following components are also used:
   * in `NATIVE-TO-ERC` mode: the ERC20 token (in fact, the ERC677 extension is used) is deployed on the Foreign network;
   * in `ERC-TO-ERC` mode: the ERC20 token (in fact, the ERC677 extension is used) is deployed on the Home network;
+  * in `ERC-TO-NATIVE` mode: The home network nodes must support consensus engine that allows using a smart contract for block reward calculation;
 * The **Validators** smart contract is deployed in both the POA.Network and the Ethereum Mainnet.
 
 ### Bridge Roles and Responsibilities
@@ -55,26 +57,89 @@ Responsibilities and roles of the bridge:
 - **User** role:
   - sends assets to Bridge contracts:
     - in `NATIVE-TO-ERC` mode: send native coins to the Home Bridge to receive ERC20 tokens from the Foreign Bridge, send ERC20 tokens to the Foreign Bridge to unlock native coins from the Home Bridge;
-    - in `ERC-TO-ERC` mode: transfer ERC20 tokens to the Foreign Bridge to mint ERC20 tokens on the Home Network, transfer ERC20 tokens to the Home Bridge to unlock ERC20 tokens on Foreign networks. 
+    - in `ERC-TO-ERC` mode: transfer ERC20 tokens to the Foreign Bridge to mint ERC20 tokens on the Home Network, transfer ERC20 tokens to the Home Bridge to unlock ERC20 tokens on Foreign networks; 
+    - in `ERC-TO-NATIVE` mode: send ERC20 tokens to the Foreign Bridge to receive native coins from the Home Bridge, send native coins to the Home Bridge to unlock ERC20 tokens from the Foreign Bridge.
 
 ## Usage
 
-### Install Dependencies
+There are two ways to deploy contracts:
+* install and use NodeJS
+* use Docker to deploy 
+
+### Deployment with NodeJS
+
+#### Install Dependencies
 ```bash
 npm install
 ```
-### Deploy
+#### Deploy
 Please the [README.md](deploy/README.md) in the `deploy` folder for instructions and .env file configuration
 
-### Test
+#### Test
 ```bash
 npm test
 ```
 
-### Flatten
+#### Flatten
+Fattened contracts can be used to verify the contract code in a block explorer like BlockScout or Etherscan.
+The following command will prepare flattened version of the contracts:
+
 ```bash
 npm run flatten
 ```
+The flattened contracts can be found in the `flats` directory.
+
+### Deployment in the Docker environment
+[Docker](https://www.docker.com/community-edition) and [Docker Compose](https://docs.docker.com/compose/install/) can be used to deploy contracts without NodeJS installed on the system. 
+If you are on Linux, we recommend you [create a docker group and add your user to it](https://docs.docker.com/install/linux/linux-postinstall/), so that you can use the CLI without `sudo`.
+
+#### Prepare the docker container
+```bash
+docker-compose up --build
+```
+_Note: The container must be rebuilt every time the code in a contract or deployment script is changed._
+
+#### Deploy the contracts
+1. Create the `.env` file in the `deploy` directory as described in the deployment [README.md](deploy/README.md).
+2. Run deployment process:
+   ```bash
+   docker-compose run bridge-contracts deploy.sh
+   ```
+   or with Linux:
+   ```bash
+   ./deploy.sh
+   ```
+
+#### Copy flatten sources (if needed)
+1. Discover the container name:
+   ```bash
+   docker-compose images bridge-contracts
+   ```
+2. In the following command, use the container name to copy the flattened contracts code to the current working directory. The contracts will be located in the `flats` directory.
+   ```bash
+   docker cp name-of-your-container:/contracts/flats ./
+   ```
+
+#### Shutdown the container
+If the container is no longer needed, it can be shutdown:
+```bash
+docker-compose down
+```
+
+### Gas Consumption
+The [GAS_CONSUMPTION](GAS_CONSUMPTION.md) file includes Min, Max, and Avg gas consumption figures for contracts associated with each bridge mode.
+
+### Testing environment
+To test the bridge scripts in ERC20-to-ERC20 mode on a testnet like Sokol or Kovan, you must deploy an ERC20 token to the foreign network.
+This can be done by running the following command:
+```bash
+cd deploy
+node testenv-deploy.js token
+```
+or with Docker:
+```bash
+./deploy.sh token
+```
 
 ## Contributing
 

contracts/ERC677BridgeToken.sol

@@ -5,7 +5,6 @@ import "openzeppelin-solidity/contracts/token/ERC20/MintableToken.sol";
 import "openzeppelin-solidity/contracts/token/ERC20/DetailedERC20.sol";
 import "./IBurnableMintableERC677Token.sol";
 import "./ERC677Receiver.sol";
-import "./libraries/Version.sol";
 
 
 contract ERC677BridgeToken is
@@ -14,14 +13,21 @@ contract ERC677BridgeToken is
     BurnableToken,
     MintableToken {
 
-    Version.Version public getTokenInterfacesVersion = Version.Version(2, 0, 0);
+    address public bridgeContract;
+
+    event ContractFallbackCallFailed(address from, address to, uint value);
 
     constructor(
         string _name,
         string _symbol,
         uint8 _decimals)
     public DetailedERC20(_name, _symbol, _decimals) {}
 
+    function setBridgeContract(address _bridgeContract) onlyOwner public {
+        require(_bridgeContract != address(0) && isContract(_bridgeContract));
+        bridgeContract = _bridgeContract;
+    }
+
     modifier validRecipient(address _recipient) {
         require(_recipient != address(0) && _recipient != address(this));
         _;
@@ -39,6 +45,10 @@ contract ERC677BridgeToken is
         return true;
     }
 
+    function getTokenInterfacesVersion() public pure returns(uint64 major, uint64 minor, uint64 patch) {
+        return (2, 0, 0);
+    }
+
     function superTransfer(address _to, uint256 _value) internal returns(bool)
     {
         return super.transfer(_to, _value);
@@ -47,8 +57,12 @@ contract ERC677BridgeToken is
     function transfer(address _to, uint256 _value) public returns (bool)
     {
         require(superTransfer(_to, _value));
-        if (isContract(_to)) {
-            contractFallback(_to, _value, new bytes(0));
+        if (isContract(_to) && !contractFallback(_to, _value, new bytes(0))) {
+            if (_to == bridgeContract) {
+                revert();
+            } else {
+                emit ContractFallbackCallFailed(msg.sender, _to, _value);
+            }
         }
         return true;
     }

contracts/IBlockReward.sol

@@ -0,0 +1,9 @@
+pragma solidity 0.4.24;
+
+
+interface IBlockReward {
+    function addExtraReceiver(uint256 _amount, address _receiver) external;
+    function mintedTotally() public view returns (uint256);
+    function mintedTotallyByBridge(address _bridge) public view returns(uint256);
+    function bridgesAllowedLength() external view returns(uint256);
+}