测试代码

.gitattributes

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+*.sol linguist-language=Solidity

.gitignore

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+build
+
+# Logs
+logs
+*.log
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+lerna-debug.log*
+.pnpm-debug.log*
+
+# Diagnostic reports (https://nodejs.org/api/report.html)
+report.[0-9]*.[0-9]*.[0-9]*.[0-9]*.json
+
+# Runtime data
+pids
+*.pid
+*.seed
+*.pid.lock
+
+# Directory for instrumented libs generated by jscoverage/JSCover
+lib-cov
+
+# Coverage directory used by tools like istanbul
+coverage
+*.lcov
+
+# nyc test coverage
+.nyc_output
+
+# Grunt intermediate storage (https://gruntjs.com/creating-plugins#storing-task-files)
+.grunt
+
+# Bower dependency directory (https://bower.io/)
+bower_components
+
+# node-waf configuration
+.lock-wscript
+
+# Compiled binary addons (https://nodejs.org/api/addons.html)
+build/Release
+
+# Dependency directories
+node_modules/
+jspm_packages/
+
+# Snowpack dependency directory (https://snowpack.dev/)
+web_modules/
+
+# TypeScript cache
+*.tsbuildinfo
+
+# Optional npm cache directory
+.npm
+
+# Optional eslint cache
+.eslintcache
+
+# Optional stylelint cache
+.stylelintcache
+
+# Microbundle cache
+.rpt2_cache/
+.rts2_cache_cjs/
+.rts2_cache_es/
+.rts2_cache_umd/
+
+# Optional REPL history
+.node_repl_history
+
+# Output of 'npm pack'
+*.tgz
+
+# Yarn Integrity file
+.yarn-integrity
+
+# dotenv environment variable files
+.env
+.env.development.local
+.env.test.local
+.env.production.local
+.env.local
+
+# parcel-bundler cache (https://parceljs.org/)
+.cache
+.parcel-cache
+
+# Next.js build output
+.next
+out
+
+# Nuxt.js build / generate output
+.nuxt
+dist
+
+# Gatsby files
+.cache/
+# Comment in the public line in if your project uses Gatsby and not Next.js
+# https://nextjs.org/blog/next-9-1#public-directory-support
+# public
+
+# vuepress build output
+.vuepress/dist
+
+# vuepress v2.x temp and cache directory
+.temp
+
+# Docusaurus cache and generated files
+.docusaurus
+
+# Serverless directories
+.serverless/
+
+# FuseBox cache
+.fusebox/
+
+# DynamoDB Local files
+.dynamodb/
+
+# TernJS port file
+.tern-port
+
+# Stores VSCode versions used for testing VSCode extensions
+.vscode-test
+
+# yarn v2
+.yarn/cache
+.yarn/unplugged
+.yarn/build-state.yml
+.yarn/install-state.gz
+.pnp.*
+
+# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio, WebStorm and Rider
+# Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
+
+# User-specific stuff
+.idea/**/workspace.xml
+.idea/**/tasks.xml
+.idea/**/usage.statistics.xml
+.idea/**/dictionaries
+.idea/**/shelf
+
+# AWS User-specific
+.idea/**/aws.xml
+
+# Generated files
+.idea/**/contentModel.xml
+
+# Sensitive or high-churn files
+.idea/**/dataSources/
+.idea/**/dataSources.ids
+.idea/**/dataSources.local.xml
+.idea/**/sqlDataSources.xml
+.idea/**/dynamic.xml
+.idea/**/uiDesigner.xml
+.idea/**/dbnavigator.xml
+
+# Gradle
+.idea/**/gradle.xml
+.idea/**/libraries
+
+# Gradle and Maven with auto-import
+# When using Gradle or Maven with auto-import, you should exclude module files,
+# since they will be recreated, and may cause churn.  Uncomment if using
+# auto-import.
+# .idea/artifacts
+# .idea/compiler.xml
+# .idea/jarRepositories.xml
+# .idea/modules.xml
+# .idea/*.iml
+# .idea/modules
+# *.iml
+# *.ipr
+
+# CMake
+cmake-build-*/
+
+# Mongo Explorer plugin
+.idea/**/mongoSettings.xml
+
+# File-based project format
+*.iws
+
+# IntelliJ
+out/
+
+# mpeltonen/sbt-idea plugin
+.idea_modules/
+
+# JIRA plugin
+atlassian-ide-plugin.xml
+
+# Cursive Clojure plugin
+.idea/replstate.xml
+
+# SonarLint plugin
+.idea/sonarlint/
+
+# Crashlytics plugin (for Android Studio and IntelliJ)
+com_crashlytics_export_strings.xml
+crashlytics.properties
+crashlytics-build.properties
+fabric.properties
+
+# Editor-based Rest Client
+.idea/httpRequests
+
+# Android studio 3.1+ serialized cache file
+.idea/caches/build_file_checksums.ser
+
+# General
+.DS_Store
+.AppleDouble
+.LSOverride
+
+# Icon must end with two \r
+Icon
+
+# Thumbnails
+._*
+
+# Files that might appear in the root of a volume
+.DocumentRevisions-V100
+.fseventsd
+.Spotlight-V100
+.TemporaryItems
+.Trashes
+.VolumeIcon.icns
+.com.apple.timemachine.donotpresent
+
+# Directories potentially created on remote AFP share
+.AppleDB
+.AppleDesktop
+Network Trash Folder
+Temporary Items
+.apdisk

LICENSE

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+                    GNU AFFERO GENERAL PUBLIC LICENSE
+                       Version 3, 19 November 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
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+<https://www.gnu.org/licenses/>.

build.sh

@@ -0,0 +1,3 @@
+#!/bin/bash
+
+truffle compile && truffle migrate --reset && cp build/contracts/DeviceManager.json frontend/src/artifacts/DeviceManager.json

contracts/DeviceManager.sol

@@ -0,0 +1,319 @@
+pragma solidity ^0.5.0;
+
+import "./MerkleProof.sol";
+import "./ECRecovery.sol";
+
+/**
+ * @title Provides base functionalities for entities.
+ */
+contract EntityBase {
+    /// @dev Entity in the device management system.
+    struct Entity {
+        // Arbitrary data in case entity wants to have some public information available.
+        string data;
+    }
+
+    /// @notice Maps owner to an Entity structure.
+    mapping (address => Entity) public ownerToEntity;
+
+    /// @dev Fired on entity data update.
+    event EntityDataUpdated(address indexed owner, string newData);
+
+    /**
+     * @notice Update entity data.
+     * @param _data Entity data.
+     */
+    function updateEntityData(string memory _data) public {
+        ownerToEntity[msg.sender].data = _data;
+
+        emit EntityDataUpdated(msg.sender, _data);
+    }
+}
+
+/**
+ * @title Provides base functionalities for devices.
+ */
+contract DeviceBase {
+    /// @dev Main device structure.
+    struct Device {
+        // Ethereum address of a device owner.
+        address owner;
+
+        // Unique device identifier. Can hold anything that fits into 32 bytes. Different from device ID.
+        // Supposed to be a public key or a representation of one, such as fingerprint of RSA/ECC 
+        // public key or simply an Ethereum address. To make identifier be an Ethereum address, 
+        // use secp256k1 curve to generate public and private key pair, run keccak256 hash function
+        // on public key and take last 20 bytes of generated hash to get Ethereum address.
+        // If a device wants to be it's own entity, use same address as in owner property.
+        bytes32 identifier;
+        
+        // Merkle root hash of metadata or simple hash of concatenated data.
+        // It is recommended to use Merkle tree to store information on device as it enables to 
+        // prove membership of specific data by providing Merkle proof without revealing whole dataset.
+        bytes32 metadataHash;
+
+        // Holds a hash of actual firmware hash. Actual firmware hash is not supposed to be stored.
+        // Plain text or hash would expose data that is meant to be private, so "hash of hash" principle 
+        // gives privacy and makes integrity verification possible.
+        bytes32 firmwareHash;
+
+        // Additional data linked to device. Can be used to store hash of encrypted firmware on IPFS.
+        //string offChainLink;
+
+        // Full public key (even though parties can exchange public key other ways then use
+        // blockchain to verify.)
+        //string publicKey;
+    }
+    
+    /// @notice State variable for storing devices. Index in the array is also a device ID.
+    /// Array can hold a maximum of 2^256-1 entries.
+    Device[] public devices;
+
+    /// @notice Keeps track of total devices for each owner.
+    mapping (address => uint) public ownerDeviceCount;
+
+    /// @dev Fired on creation of new device.
+    event DeviceCreated(uint indexed deviceId, address indexed owner, bytes32 identifier, bytes32 metadataHash, bytes32 firmwareHash);
+
+    /// @dev Modifier for ensuring that the message sender is owner of provided device ID.
+    modifier onlyOwnerOf(uint _deviceId) {
+        require(devices[_deviceId].owner == msg.sender, "Only for device owner");
+        _;
+    }
+
+    /**
+     * @notice Creates and saves device into storage. Emits DeviceCreated. 
+     * @param _identifier Unique device identifier, such as fingerprint of RSA/ECC public key or Ethereum address (recommended).
+     * @param _metadataHash Merkle root hash of metadata (recommended) or simple hash of concatenated metadata.
+     * @param _firmwareHash Hash of actual firmware hash.
+     * @return Created device ID.
+     */
+    function createDevice(bytes32 _identifier, bytes32 _metadataHash, bytes32 _firmwareHash) public returns (uint) {
+        Device memory newDevice = Device(msg.sender, _identifier, _metadataHash, _firmwareHash);
+        uint deviceId = devices.push(newDevice) - 1;
+        ownerDeviceCount[msg.sender]++;
+
+        emit DeviceCreated(deviceId, msg.sender, _identifier, _metadataHash, _firmwareHash);
+        return deviceId;
+    }
+}
+
+/**
+ * @title Provides extra functionalities for devices.
+ */
+contract DeviceHelper is DeviceBase {
+   /**
+     * @notice Gets all devices owned by specified address. 
+     * @dev Use this function instead of filtering DeviceCreated event since devices could have been transferred between owners.
+     * @param _owner Owner address.
+     * @return Array of device IDs.
+     */
+    function getDevicesByOwner(address _owner) public view returns (uint[] memory) {
+        uint[] memory deviceIds = new uint[](ownerDeviceCount[_owner]);
+        uint counter = 0;
+        for (uint i = 0; i < devices.length; i++) {
+            if (devices[i].owner == _owner) {
+                deviceIds[counter] = i;
+                counter++;
+            }
+        }
+        return deviceIds;
+    }
+
+    /**
+     * @notice Checks if device is also an entity. 
+     * @param _deviceId ID of a  device.
+     * @return Boolean status.
+     */
+    function isDeviceAnEntity(uint _deviceId) public view returns (bool) {
+        return devices[_deviceId].owner == address(uint160(uint256(devices[_deviceId].identifier)));
+    }
+
+    /**
+     * @notice Checks if provided leaf is a member of metadata contained in Merkle tree. 
+     * Assumes that each pair of leaves and each pair of pre-images are sorted.
+     * @param _deviceId ID of a device containing metadata hash.
+     * @param _proof Merkle proof containing sibling hashes on the branch from the leaf to the root of the Merkle tree.
+     * @param _leaf Leaf of Merkle tree.
+     * @return Boolean status.
+     */
+    function isValidMetadataMember(uint _deviceId, bytes32[] memory _proof, bytes32 _leaf) public view returns (bool) {
+        return MerkleProof.verifyProof(_proof, devices[_deviceId].metadataHash, _leaf);
+    }
+
+    /**
+     * @notice Checks if provided firmware hash is equal to firmware hash device property. 
+     * @param _deviceId ID of a device containing firmware hash.
+     * @param _firmwareHash Firmware hash (not the actual hash).
+     * @return Boolean status.
+     */
+    function isValidFirmwareHash(uint _deviceId, bytes32 _firmwareHash) public view returns (bool) {
+        return devices[_deviceId].firmwareHash == _firmwareHash;
+    }
+
+    /**
+     * @notice Validate authenticity of message signed by Etherium private key.
+     * On-chain validation is available only for Ethereum signed messages.
+     * @param _deviceId ID of a device that signed the message.
+     * @param _messageHash Hash of sent message.
+     * @param _signature Signature generated using web3.eth.sign().
+     * @return Boolean status.
+     */
+    function isValidEthMessage(uint _deviceId, bytes32 _messageHash, bytes memory _signature) public view returns (bool) {
+        return ECRecovery.recover(_messageHash, _signature) == address(uint160(uint256(devices[_deviceId].identifier)));
+    }
+}
+
+/**
+ * @title Provides base functionalities for signatures.
+ */
+contract SignatureBase {
+    /// @dev Main signature structure.
+    struct Signature {
+        // Ethereum address of the signer.
+        address signer;
+
+        // ID of device to sign.
+        uint deviceId;
+
+        // Using 256 bits ensures no overflow on year 2038 (Unix seconds).
+        uint expiryTime;
+
+        // Updates to true once signer decides to revoke signature.
+        bool revoked;
+    }
+
+    /// @notice State variable for storing signatures. Index in the array is also a signature ID.
+    /// Array can hold a maximum of 2^256-1 entries.
+    Signature[] public signatures;
+
+    /// @notice Keeps track of total signatures for each device.
+    mapping (uint => uint) public deviceSignatureCount;
+    
+    /// @dev Fired when an address signs a device.
+    event DeviceSigned(uint indexed signatureId, uint indexed deviceId, address indexed signer, uint expiryTime);
+
+    /// @dev Fired when signature is revoked.
+    event SignatureRevoked(uint indexed signatureId, uint indexed deviceId);
+
+    /// @dev Modifier for ensuring that the device hasn't been signed already.
+    modifier notSigned(uint _deviceId) {
+        require(deviceSignatureCount[_deviceId] == 0, "Must not be signed");
+        _;
+    }
+
+    /**
+     * @notice Signs a device and signature into storage. Emits DeviceSigned. 
+     * @param _deviceId ID of to be signed device.
+     * @param _expiryTime Expiry time in Unix seconds.
+     * @return Created signature ID.
+     */
+    function signDevice(uint _deviceId, uint _expiryTime) public returns (uint) {
+        Signature memory signature = Signature(msg.sender, _deviceId, _expiryTime, false);
+        uint signatureId = signatures.push(signature) - 1;
+        deviceSignatureCount[_deviceId]++;
+
+        emit DeviceSigned(signatureId, _deviceId, msg.sender, _expiryTime);
+        return signatureId;
+    }
+
+    /**
+     * @notice Revokes a signature. Emits SignatureRevoked. 
+     * @param _signatureId ID of to be revoked signature.
+     */
+    function revokeSignature(uint _signatureId) public {
+        require(signatures[_signatureId].signer == msg.sender, "Only for creator of the signature");
+        require(signatures[_signatureId].revoked == false, "Signature mustn't be revoked already");
+        Signature storage signature = signatures[_signatureId];
+        signature.revoked = true;
+        deviceSignatureCount[signature.deviceId]--;
+
+        emit SignatureRevoked(_signatureId, signature.deviceId);
+    }
+}
+
+/**
+ * @title Provides extra functionalities for signatures.
+ */
+contract SignatureHelper is SignatureBase {
+    /**
+     * @notice Gets all signatures for specific device. 
+     * @dev Use this function instead of filtering DeviceSigned event since signatures could have been revoked.
+     * @param _deviceId ID of a device.
+     * @return Array of signature IDs.
+     */
+    function getActiveSignaturesForDevice(uint _deviceId) public view returns (uint[] memory) {
+        uint[] memory signatureIds = new uint[](deviceSignatureCount[_deviceId]);
+        uint counter = 0;
+        for (uint i = 0; i < signatures.length; i++) {
+            if (signatures[i].deviceId == _deviceId && signatures[i].revoked == false) {
+                signatureIds[counter] = i;
+                counter++;
+            }
+        }
+        return signatureIds;
+    }
+}
+
+/**
+ * @title Enriches devices giving them option to be updated only if not signed already.
+ */
+contract DeviceUpdatable is DeviceHelper, SignatureHelper {
+    /// @dev Fired on device ownership transfer, keeps track of historical device owners.
+    event DeviceTransfered(uint indexed deviceId, address oldOwner, address newOwner);
+    
+    /// @dev Fired on device property update, keeps track of historical property values.
+    event DevicePropertyUpdated(uint indexed deviceId, bytes32 indexed property, bytes32 newValue);
+
+    /**
+     * @notice Transfer device ownership from one external account to another. Emits DeviceTransfered.
+     * @param _deviceId ID of to be transferred device.
+     * @param _to Address of new owner.
+     */
+    function transferDevice(uint _deviceId, address _to) public onlyOwnerOf(_deviceId) notSigned(_deviceId) {
+        address currentOwner = devices[_deviceId].owner;
+        devices[_deviceId].owner = _to;
+        ownerDeviceCount[msg.sender]--;
+        ownerDeviceCount[_to]++;
+
+        emit DeviceTransfered(_deviceId, currentOwner, _to);
+    } 
+
+    /**
+     * @notice Update device with new identifier. Emits DevicePropertyUpdated.
+     * @param _deviceId ID of a device.
+     * @param _newIdentifier New identifier.
+     */
+    function updateIdentifier(uint _deviceId, bytes32 _newIdentifier) public onlyOwnerOf(_deviceId) notSigned(_deviceId) {
+        devices[_deviceId].identifier = _newIdentifier;
+
+        emit DevicePropertyUpdated(_deviceId, "identifier", _newIdentifier);
+    }
+
+    /**
+     * @notice Update device with new metadata hash. Emits DevicePropertyUpdated.
+     * @param _deviceId ID of a device.
+     * @param _newMetadataHash New metadata hash.
+     */
+    function updateMetadataHash(uint _deviceId, bytes32 _newMetadataHash) public onlyOwnerOf(_deviceId) notSigned(_deviceId) {
+        devices[_deviceId].metadataHash = _newMetadataHash;
+
+        emit DevicePropertyUpdated(_deviceId, "metadata", _newMetadataHash);
+    }
+
+    /**
+     * @notice Update device with new firmware hash. Emits DevicePropertyUpdated.
+     * @param _deviceId ID of a device.
+     * @param _newFirmwareHash New firmware hash.
+     */
+    function updateFirmwareHash(uint _deviceId, bytes32 _newFirmwareHash) public onlyOwnerOf(_deviceId) notSigned(_deviceId) {
+        devices[_deviceId].firmwareHash = _newFirmwareHash;
+
+        emit DevicePropertyUpdated(_deviceId, "firmware", _newFirmwareHash);
+    }
+}
+
+/// @title Device manager core contract.
+contract DeviceManager is EntityBase, DeviceUpdatable {
+    /// @dev Merges contracts.
+}

contracts/ECRecovery.sol

@@ -0,0 +1,68 @@
+pragma solidity ^0.5.0;
+
+/**
+ * @title Elliptic curve signature operations
+ * @dev Based on https://gist.github.com/axic/5b33912c6f61ae6fd96d6c4a47afde6d
+ * TODO Remove this library once solidity supports passing a signature to ecrecover.
+ * See https://github.com/ethereum/solidity/issues/864
+ * Source: https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/ECRecovery.sol
+ */
+library ECRecovery {
+    /**
+     * @dev Recover signer address from a message by using their signature
+     * @param _hash bytes32 message, the hash is the signed message. What is recovered is the signer address.
+     * @param _signature bytes signature, the signature is generated using web3.eth.sign()
+     */
+    function recover(bytes32 _hash, bytes memory _signature)
+        internal
+        pure
+        returns (address)
+    {
+        bytes32 r;
+        bytes32 s;
+        uint8 v;
+
+        // Check the signature length
+        if (_signature.length != 65) {
+            return (address(0));
+        }
+
+        // Divide the signature in r, s and v variables
+        // ecrecover takes the signature parameters, and the only way to get them
+        // currently is to use assembly.
+        // solium-disable-next-line security/no-inline-assembly
+        assembly {
+            r := mload(add(_signature, 32))
+            s := mload(add(_signature, 64))
+            v := byte(0, mload(add(_signature, 96)))
+        }
+
+        // Version of signature should be 27 or 28, but 0 and 1 are also possible versions
+        if (v < 27) {
+            v += 27;
+        }
+
+        // If the version is correct return the signer address
+        if (v != 27 && v != 28) {
+            return (address(0));
+        } else {
+            // solium-disable-next-line arg-overflow
+            return ecrecover(_hash, v, r, s);
+        }
+    }
+
+    /**
+     * @dev prefix a bytes32 value with "\x19Ethereum Signed Message:" and hash the result
+     */
+    function toEthSignedMessageHash(bytes32 _hash)
+        internal
+        pure
+        returns (bytes32)
+    {
+        // 32 is the length in bytes of hash,
+        // enforced by the type signature above
+        return keccak256(
+            abi.encodePacked("\x19Ethereum Signed Message:\n32", _hash)
+        );
+    }
+}

contracts/MerkleProof.sol

@@ -0,0 +1,42 @@
+pragma solidity ^0.5.0;
+
+/**
+ * @title MerkleProof
+ * @dev Merkle proof verification based on https://github.com/ameensol/merkle-tree-solidity/blob/master/src/MerkleProof.sol
+ * Source: https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/MerkleProof.sol
+ */
+library MerkleProof {
+    /**
+     * @dev Verifies a Merkle proof proving the existence of a leaf in a Merkle tree. Assumes that each pair of leaves
+     * and each pair of pre-images are sorted.
+     * @param _proof Merkle proof containing sibling hashes on the branch from the leaf to the root of the Merkle tree
+     * @param _root Merkle root
+     * @param _leaf Leaf of Merkle tree
+     */
+    function verifyProof(
+        bytes32[] memory _proof,
+        bytes32 _root,
+        bytes32 _leaf
+    )
+        internal
+        pure
+        returns (bool)
+    {
+        bytes32 computedHash = _leaf;
+
+        for (uint256 i = 0; i < _proof.length; i++) {
+            bytes32 proofElement = _proof[i];
+
+            if (computedHash < proofElement) {
+                // Hash(current computed hash + current element of the proof)
+                computedHash = keccak256(abi.encodePacked(computedHash, proofElement));
+            } else {
+                // Hash(current element of the proof + current computed hash)
+                computedHash = keccak256(abi.encodePacked(proofElement, computedHash));
+            }
+        }
+
+        // Check if the computed hash (root) is equal to the provided root
+        return computedHash == _root;
+    }
+}

contracts/Migrations.sol

@@ -0,0 +1,23 @@
+pragma solidity ^0.5.0;
+
+contract Migrations {
+    address public owner;
+    uint public last_completed_migration;
+
+    constructor() public {
+        owner = msg.sender;
+    }
+
+    modifier restricted() {
+        if (msg.sender == owner) _;
+    }
+
+    function setCompleted(uint completed) public restricted {
+        last_completed_migration = completed;
+    }
+
+    function upgrade(address new_address) public restricted {
+        Migrations upgraded = Migrations(new_address);
+        upgraded.setCompleted(last_completed_migration);
+    }
+}

frontend/.gitignore

@@ -0,0 +1,21 @@
+# See https://help.github.com/ignore-files/ for more about ignoring files.
+
+# dependencies
+/node_modules
+
+# testing
+/coverage
+
+# production
+/build
+
+# misc
+.DS_Store
+.env.local
+.env.development.local
+.env.test.local
+.env.production.local
+
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*

frontend/package.json

@@ -0,0 +1,25 @@
+{
+  "name": "frontend",
+  "version": "0.1.0",
+  "private": true,
+  "dependencies": {
+    "antd": "3.8.1",
+    "elliptic": "6.4.1",
+    "ethereumjs-util": "5.2.0",
+    "ethereumjs-wallet": "0.6.2",
+    "merkle-tree-solidity": "1.0.8",
+    "react": "16.4.2",
+    "react-dom": "16.4.2",
+    "react-router-dom": "4.3.1",
+    "react-scripts": "1.1.4",
+    "secp256k1": "^4.0.3",
+    "truffle-contract": "3.0.6",
+    "web3": "0.20.6"
+  },
+  "scripts": {
+    "start": "react-scripts start",
+    "build": "react-scripts build",
+    "test": "react-scripts test --env=jsdom",
+    "eject": "react-scripts eject"
+  }
+}

frontend/public/index.html

@@ -0,0 +1,40 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="utf-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
+    <meta name="theme-color" content="#000000">
+    <!--
+      manifest.json provides metadata used when your web app is added to the
+      homescreen on Android. See https://developers.google.com/web/fundamentals/engage-and-retain/web-app-manifest/
+    -->
+    <link rel="manifest" href="%PUBLIC_URL%/manifest.json">
+    <link rel="shortcut icon" href="%PUBLIC_URL%/favicon.ico">
+    <!--
+      Notice the use of %PUBLIC_URL% in the tags above.
+      It will be replaced with the URL of the `public` folder during the build.
+      Only files inside the `public` folder can be referenced from the HTML.
+
+      Unlike "/favicon.ico" or "favicon.ico", "%PUBLIC_URL%/favicon.ico" will
+      work correctly both with client-side routing and a non-root public URL.
+      Learn how to configure a non-root public URL by running `npm run build`.
+    -->
+    <title>IoT Device Management</title>
+  </head>
+  <body>
+    <noscript>
+      You need to enable JavaScript to run this app.
+    </noscript>
+    <div id="root"></div>
+    <!--
+      This HTML file is a template.
+      If you open it directly in the browser, you will see an empty page.
+
+      You can add webfonts, meta tags, or analytics to this file.
+      The build step will place the bundled scripts into the <body> tag.
+
+      To begin the development, run `npm start` or `yarn start`.
+      To create a production bundle, use `npm run build` or `yarn build`.
+    -->
+  </body>
+</html>

frontend/public/manifest.json

@@ -0,0 +1,15 @@
+{
+  "short_name": "IoT Device Management",
+  "name": "IoT Device Management",
+  "icons": [
+    {
+      "src": "favicon.ico",
+      "sizes": "64x64 32x32 24x24 16x16",
+      "type": "image/x-icon"
+    }
+  ],
+  "start_url": "./index.html",
+  "display": "standalone",
+  "theme_color": "#000000",
+  "background_color": "#ffffff"
+}

frontend/src/App.css

@@ -0,0 +1,9 @@
+@import '~antd/dist/antd.css';
+
+.loading-spin {
+  text-align: center;
+  border-radius: 4px;
+  margin-bottom: 20px;
+  padding: 30px 50px;
+  margin: 10px 0;
+}

frontend/src/App.js

@@ -0,0 +1,190 @@
+import getWeb3 from './utils/web3';
+import DeviceManager from './DeviceManager';
+
+import React, { Component } from 'react';
+import { BrowserRouter as Router, Route, Link } from 'react-router-dom';
+import './App.css';
+
+import Home from './components/Home';
+import RegisterDevice from './components/RegisterDevice';
+import ManageDevices from './components/ManageDevices';
+import EditEntity from './components/EditEntity';
+import LookupEntity from './components/LookupEntity';
+import ManageDevice from './components/ManageDevice';
+import LookupDevice from './components/LookupDevice';
+import CheckSignature from './components/CheckSignature';
+
+import { Layout, Menu, Icon, Tag, Alert, Spin } from 'antd';
+
+const { SubMenu } = Menu;
+const { Header, Content, Footer, Sider } = Layout;
+
+class App extends Component {
+  constructor(props) {
+    super(props);
+
+    this.state = {
+      web3: null,
+      deviceManagerInstance: null,
+      errorMessage: '',
+      loading: true
+    }
+  }
+
+  async componentWillMount() {
+    getWeb3.then(results => {
+      this.setState({
+        web3: results.web3,
+      });
+
+      console.log(`Using address: ${this.state.web3.eth.accounts[0]}`);
+
+      return DeviceManager.then(instance => {
+        this.setState({
+          loading: false,
+          deviceManagerInstance: instance
+        });
+  
+        console.log(`Contract address: ${instance.address}`);
+      }).catch(error => {
+        console.log(error);
+        this.setState({
+          errorMessage: error.message,
+          loading: false
+        });
+      });
+    }).catch(() => {
+      let errorMessage = 'Error finding web3. Please install MetaMask.';
+      console.log(errorMessage);
+      this.setState({
+        errorMessage: errorMessage,
+        loading: false
+      });
+    });
+  }
+
+  mainContent() {
+    if (!this.state.loading) {
+      let childComponent;
+
+      if (this.state.web3 == null || this.state.deviceManagerInstance == null) {
+        childComponent = <div>
+          <h1>Resolve the following issues to continue</h1>
+          <Alert
+            message="Error"
+            description={this.state.errorMessage}
+            type="error"
+            showIcon
+          />
+        </div>
+      } else {
+        childComponent = <div>
+          <Route exact path="/" component={Home} />
+          <Route path="/edit-entity" component={EditEntity} />
+          <Route path="/lookup-entity/:address?" component={LookupEntity} />
+          <Route path="/register-device" component={RegisterDevice} />
+          <Route path="/manage-devices" component={ManageDevices} />
+          <Route path="/manage-device/:deviceId" component={ManageDevice} />
+          <Route path="/lookup-device" component={LookupDevice} />
+          <Route path="/check-signature/:signatureId" component={CheckSignature} />
+        </div>
+      }
+      return (
+        <div>
+          {childComponent}
+        </div>
+      );
+    }
+  }
+  render() {
+    let statusTag;
+
+    if (this.state.web3 == null) {
+      statusTag = <Tag color="red">Web3 missing</Tag>;
+    } else if (this.state.deviceManagerInstance == null) {
+      statusTag = <Tag color="red">Network error</Tag>;
+    } else {
+      statusTag = <Tag color="green">OK</Tag>;
+    }
+
+    return (
+      <Router>
+        <Layout style={{ height: "100vh" }}>
+          <Header className="header">
+            <Menu
+              theme="dark"
+              mode="horizontal"
+              defaultSelectedKeys={['1']}
+              style={{ lineHeight: '64px' }}
+            >
+              <Menu.Item key="1">
+                <Link to="/" className="nav-text">IoT Device Management</Link>
+              </Menu.Item>
+              <Menu.Item key="2" style={{ float: 'right' }}>
+                Status: {statusTag}
+              </Menu.Item>
+            </Menu>
+          </Header>
+          <Content style={{ padding: '24px 50px' }}>
+            <Layout style={{ padding: '24px 0', background: '#fff' }}>
+              <Sider width={200} style={{ background: '#fff' }}>
+                <Menu
+                  mode="inline"
+                  defaultSelectedKeys={['']}
+                  defaultOpenKeys={['sub1', 'sub2', 'sub3']}
+                  style={{ height: '100%' }}
+                >
+                  <SubMenu key="sub1" title={<span><Icon type="user" />Entities</span>}>
+                    <Menu.Item key="1">
+                      <Link to="/edit-entity" className="nav-text">Edit</Link>
+                    </Menu.Item>
+                    <Menu.Item key="2">
+                      <Link to="/lookup-entity" className="nav-text">Lookup</Link>
+                    </Menu.Item>
+                  </SubMenu>
+                  <SubMenu key="sub2" title={<span><Icon type="laptop" />Devices</span>}>
+                    <Menu.Item key="3">
+                      <Link to="/register-device" className="nav-text">Register</Link>
+                    </Menu.Item>
+                    <Menu.Item key="4">
+                      <Link to="/manage-devices" className="nav-text">Manage</Link>
+                    </Menu.Item>
+                    <Menu.Item key="5">
+                      <Link to="/lookup-device" className="nav-text">Lookup</Link>
+                    </Menu.Item>
+                    {/*
+                    <Menu.Item key="5">
+                      <Link to="#" className="nav-text">Filter</Link>
+                    </Menu.Item>
+                    */}
+                  </SubMenu>
+                  {/*
+                  <SubMenu key="sub3" title={<span><Icon type="form" />Signatures</span>}>
+
+                    <Menu.Item key="6">
+                      <Link to="#" className="nav-text">Sign</Link>
+                    </Menu.Item>
+                    <Menu.Item key="7">
+                      <Link to="/check-signature" className="nav-text">Check</Link>
+                    </Menu.Item>
+                  </SubMenu>
+                  */}
+                </Menu>
+              </Sider>
+              <Content style={{ padding: '0 24px', minHeight: 400 }}>
+                <Spin spinning={this.state.loading} className="loading-spin">
+                  {this.mainContent()}
+                </Spin>
+              </Content>
+            </Layout>
+          </Content>
+          <Footer style={{ textAlign: 'center' }}>
+            IoT Device Management &copy; 2024 物联网大作业
+        </Footer>
+        </Layout>
+      </Router>
+    );
+  }
+}
+
+export default App;

frontend/src/DeviceManager.js

@@ -0,0 +1,28 @@
+import getWeb3 from './utils/web3';
+import TruffleContract from 'truffle-contract';
+import DeviceManagerArtifact from './artifacts/DeviceManager.json';
+
+let web3;
+let DeviceManager = new Promise(function (resolve, reject) {
+  getWeb3.then(results => {
+    web3 = results.web3;
+
+    const deviceManager = TruffleContract(DeviceManagerArtifact);
+    deviceManager.setProvider(web3.currentProvider);
+
+    return deviceManager.deployed().then(instance => {
+      console.log('Initiating DeviceManager instance...');
+      resolve(instance);
+    }).catch(error => {
+      reject(error);
+    });
+  }).catch(error => {
+    reject(error);
+  });
+});
+
+export function getDefaultAccount() {
+  return web3.eth.accounts[0];
+}
+
+export default DeviceManager;

frontend/src/components/CheckSignature.js

@@ -0,0 +1,99 @@
+import getWeb3 from '../utils/web3';
+import DeviceManager from '../DeviceManager';
+
+import React, { Component } from 'react';
+import { Link } from 'react-router-dom';
+import { Tag, Divider, Spin, Alert } from 'antd';
+
+class CheckSignature extends Component {
+  constructor(props) {
+    super(props);
+
+    this.state = {
+      signatureId: this.props.match.params.signatureId,
+      loading: true,
+      showError: false
+    }
+  }
+
+  componentWillReceiveProps({ match }) {
+    this.setState({
+      ...this.state,
+      showError: false,
+      signatureId: match.params.signatureId
+    }, () => this.updateSignatureData());
+  }
+
+  async componentWillMount() {
+    try {
+      let web3 = (await getWeb3).web3;
+      let instance = await DeviceManager;
+
+      this.setState({
+        web3,
+        instance
+      });
+
+      await this.updateSignatureData();
+    } catch (error) {
+      console.log(error);
+      //message.error(error.message);
+      this.setState({
+        loading: false,
+        showError: true
+      })
+    }
+  }
+
+  async updateSignatureData() {
+    try {
+      const { instance, signatureId } = this.state;
+      let signature = await instance.signatures(signatureId);
+
+      this.setState({
+        loading: false,
+        signer: signature[0],
+        deviceId: signature[1].toNumber(),
+        expiryTime: signature[2].toNumber(),
+        revoked: signature[3],
+      });
+    } catch (error) {
+      console.log(error);
+      //message.error(error.message);
+      this.setState({
+        loading: false,
+        showError: true
+      })
+    }
+  }
+
+  render() {
+    const { loading, showError, signer, deviceId, expiryTime, revoked } = this.state;
+
+    return (
+      <div>
+        <Spin spinning={loading} className="loading-spin">
+          {loading === false && showError === false &&
+            <div>
+              <h3><div style={{ marginBottom: '20px' }}>Signature created by {signer}&nbsp;</div></h3>
+              <Divider />
+              <div style={{ marginBottom: '20px' }}>For device with &nbsp;<Link to={"/manage-device/" + deviceId}><Tag>ID {deviceId}</Tag></Link></div>
+              <div style={{ marginBottom: '20px' }}>Expires on {new Date(expiryTime * 1000).toString()}&nbsp;</div>
+              {revoked === true ? <div style={{ marginBottom: '20px' }}><strong>This signature has been revoked!</strong>&nbsp;</div> : <div></div>}
+            </div>
+          }
+          {loading === false && showError &&
+            <Alert
+              message="Error"
+              description="Error loading signature: invalid ID format or signature doesn't exist."
+              type="error"
+              showIcon
+            />
+          }
+        </Spin >
+      </div>
+    );
+  }
+}
+
+export default CheckSignature;

frontend/src/components/EditEntity.js

@@ -0,0 +1,135 @@
+import getWeb3 from '../utils/web3';
+import DeviceManager, { getDefaultAccount } from '../DeviceManager';
+
+import React, { Component } from 'react';
+import { Card, Input, Button, Icon, message, notification } from 'antd';
+
+const { TextArea } = Input;
+
+const openNotificationWithIcon = (type, message, description) => {
+  notification[type]({
+    message,
+    description
+  });
+};
+
+class EditEntity extends Component {
+  constructor(props) {
+    super(props);
+
+    this.state = {
+      myData: null,
+      showEdit: false,
+      web3: null,
+      instance: null,
+      loading: true,
+      filter: null
+    }
+
+    this.toggleEdit = this.toggleEdit.bind(this);
+    this.commonChange = this.commonChange.bind(this);
+    this.saveMyData = this.saveMyData.bind(this);
+    this.updateMyData = this.updateMyData.bind(this);
+    this.watchForChanges = this.watchForChanges.bind(this);
+  }
+
+  async componentWillMount() {
+    try {
+      let results = await getWeb3;
+      let instance = await DeviceManager;
+
+      this.setState({
+        web3: results.web3,
+        instance
+      });
+
+      await this.updateMyData();
+
+    } catch (error) {
+      console.log(error);
+      message.error(error.message);
+    }
+  }
+
+  watchForChanges() {
+    let filter = this.state.web3.eth.filter('latest', (error, result) => {
+      if (!error) {
+        openNotificationWithIcon('success', 'Transaction mined', 'Your entity data has been updated.');
+        this.state.filter.stopWatching();
+        this.updateMyData();
+      } else {
+        console.error(error);
+      }
+    });
+
+    this.setState({
+      filter
+    })
+  }
+
+  async updateMyData() {
+    try {
+      let result = await this.state.instance.ownerToEntity(getDefaultAccount());
+      this.setState({
+        myData: result,
+        myDataNew: result,
+        loading: false
+      })
+    } catch (error) {
+      console.log(error);
+      message.error(error.message);
+    }
+  }
+
+  toggleEdit() {
+    this.setState(prevState => ({
+      showEdit: !prevState.showEdit
+    }));
+  }
+
+  commonChange(e) {
+    this.setState({
+      [e.target.name]: e.target.value
+    });
+  }
+
+  async saveMyData() {
+    try {
+      if (this.state.myDataNew !== this.state.myData) {
+        let instance = await DeviceManager;
+        await instance.updateEntityData(this.state.myDataNew, { from: getDefaultAccount() });
+        this.watchForChanges();
+        openNotificationWithIcon('info', 'Transaction sent', 'Once mined, your entity data will be updated.');
+        this.setState({
+          loading: true,
+        });
+      }
+      this.toggleEdit();
+    } catch (error) {
+      console.log(error);
+      message.error(error.message);
+    }
+  }
+
+  render() {
+    return (
+      <div>
+        <p>
+          Edit your entity details.
+        </p>
+        <Card style={{ maxWidth: '500px' }} loading={this.state.loading} title={getDefaultAccount()}>
+          {this.state.showEdit ?
+            <div>
+              <TextArea name="myDataNew" value={this.state.myDataNew} onChange={this.commonChange} />
+              <Button type="primary" style={{ marginTop: '10px' }} onClick={this.saveMyData}>Save</Button>
+            </div>
+            :
+            <p>{this.state.myData || <em>empty data</em>} <a><Icon type="edit" onClick={this.toggleEdit} /></a></p>
+          }
+        </Card>
+      </div>
+    )
+  }
+}
+
+export default EditEntity;

frontend/src/components/Home.js

@@ -0,0 +1,13 @@
+import React, { Component } from 'react';
+
+class Home extends Component {
+    render() {
+        return (
+            <div>
+                Using blockchain for registration and control of IoT devices.
+            </div>
+        )
+    }
+}
+
+export default Home;

frontend/src/components/LookupDevice.js

@@ -0,0 +1,56 @@
+import React, { Component } from 'react';
+import ManageDevice from './ManageDevice';
+
+import { Input, Divider } from 'antd';
+
+const { Search } = Input;
+
+class LookupDevice extends Component {
+  constructor(props) {
+    super(props);
+
+    this.state = {
+      match: {
+        params: {
+          deviceId: 1
+        }
+      },
+      searched: false
+    }
+  }
+
+  lookupDevice(value) {
+    this.setState({
+      match: {
+        params: {
+          deviceId: value
+        }
+      },
+      searched: true
+    })
+  }
+
+  render() {
+    return (
+      <div>
+        <p>
+          Search for any device.
+        </p>
+        <Search
+          placeholder="Device ID"
+          onSearch={value => this.lookupDevice(value)}
+          size="large"
+          enterButton
+        />
+        {this.state.searched &&
+          <div>
+            <Divider />
+            <ManageDevice match={this.state.match} />
+          </div>
+        }
+      </div>
+    )
+  }
+}
+
+export default LookupDevice;

frontend/src/components/LookupEntity.js

@@ -0,0 +1,121 @@
+import DeviceManager, { getDefaultAccount } from '../DeviceManager';
+import ethUtil from 'ethereumjs-util';
+
+import React, { Component } from 'react';
+import { Link } from 'react-router-dom';
+import { Button, Tag, Card, Input, Divider, Timeline, message } from 'antd';
+
+const Search = Input.Search;
+
+const eventsToSave = ['EntityDataUpdated', 'DeviceCreated', 'DeviceTransfered', 'DeviceSigned'];
+
+class LookupEntity extends Component {
+  constructor(props) {
+    super(props);
+
+    this.state = {
+      loading: false,
+      searchValue: '',
+      address: this.props.match.params.address,
+      data: [],
+      searched: false
+    }
+
+    this.lookupEntity = this.lookupEntity.bind(this);
+  }
+
+  componentWillMount() {
+    const { address } = this.state;
+    if (address != null) {
+      this.reloadWithAddress(address);
+    }
+  }
+
+  reloadWithAddress(address) {
+    this.setState({
+      searchValue: address
+    })
+    this.lookupEntity(address).then(() => { });
+  }
+
+  async lookupEntity(address) {
+    if (!ethUtil.isValidAddress(address)) {
+      message.error('Invalid entity address.');
+      return;
+    }
+
+    this.setState({
+      loading: true
+    });
+
+    try {
+      let instance = await DeviceManager;
+
+      let allEvents = instance.allEvents({ fromBlock: 0, toBlock: 'latest' });
+      allEvents.get((error, logs) => {
+        let filteredData = logs.filter(el => eventsToSave.includes(el.event) && (el.args.owner === address || el.args.oldOwner === address || el.args.newOwner === address || el.args.signer === address));
+        if (!error) {
+          this.setState({
+            address: address,
+            data: filteredData,
+            loading: false,
+            searched: true
+          })
+        }
+      });
+    } catch (error) {
+      console.log(error);
+      message.error(error.message);
+    }
+  }
+
+  render() {
+    return (
+      <div>
+        <p>
+          Search for any entity.
+        </p>
+        <Search
+          placeholder="Input address"
+          onSearch={value => this.lookupEntity(value)}
+          size="large"
+          enterButton
+          value={this.state.searchValue}
+          onChange={(e) => this.setState({ searchValue: e.target.value })}
+        />
+        <br /><br />
+        <Button size="small" onClick={() => this.setState({ searchValue: getDefaultAccount() })}>Set to my address</Button>
+        {this.state.searched &&
+          <div>
+            <Divider />
+            <Card loading={this.state.loading} title={'Historical events for entity (oldest to newest)'}>
+              {this.state.data.length !== 0 ?
+                <div>
+                  <p style={{ marginBottom: '20px' }}>Events that are filtered are {eventsToSave.join(', ')} </p>
+                  <Timeline style={{ marginTop: '10px' }}>
+                    {this.state.data.map(el => {
+                      if (el.event === 'EntityDataUpdated')
+                        return <Timeline.Item>Entity data updated to <code>{el.args.newData}</code></Timeline.Item>
+                      if (el.event === 'DeviceCreated')
+                        return <Timeline.Item color='green'>Created device with &nbsp;<Link to={"/manage-device/" + el.args.deviceId.toNumber()}><Tag>ID {el.args.deviceId.toNumber()}</Tag></Link>, identifier <code>{el.args.identifier}</code>, metadata hash <code>{el.args.metadataHash}</code> and firmware hash <code>{el.args.firmwareHash}</code></Timeline.Item>
+                      if (el.event === 'DeviceTransfered')
+                        return <Timeline.Item color='orange'>Device with &nbsp;<Link to={"/manage-device/" + el.args.deviceId.toNumber()}><Tag>ID {el.args.deviceId.toNumber()}</Tag></Link>transfered {el.args.newOwner === this.state.address && <span>from &nbsp;<Tag onClick={() => this.reloadWithAddress(el.args.oldOwner)}>{el.args.oldOwner}</Tag></span>}{el.args.oldOwner === this.state.address && <span>to &nbsp;<Tag onClick={() => this.reloadWithAddress(el.args.newOwner)}>{el.args.newOwner}</Tag></span>}</Timeline.Item>
+                      if (el.event === 'DeviceSigned')
+                        return <Timeline.Item color='purple'>Signed device with &nbsp;<Link to={"/manage-device/" + el.args.deviceId.toNumber()}><Tag>ID {el.args.deviceId.toNumber()}</Tag></Link></Timeline.Item>
+                      else
+                        return null
+                    })}
+                  </Timeline>
+                </div>
+                :
+                <p><em>empty</em></p>
+              }
+            </Card>
+          </div>
+        }
+      </div>
+    )
+  }
+}
+
+export default LookupEntity;

frontend/src/components/ManageDevice.js

@@ -0,0 +1,357 @@
+import getWeb3 from '../utils/web3';
+import DeviceManager, { getDefaultAccount } from '../DeviceManager';
+import { addHexPrefix } from 'ethereumjs-util';
+
+import React, { Component } from 'react';
+import { Link } from 'react-router-dom';
+import { Tag, Button, Input, Card, Timeline, Divider, Spin, Alert, Icon, notification, message } from 'antd';
+
+const openNotificationWithIcon = (type, message, description) => {
+  notification[type]({
+    message,
+    description
+  });
+};
+
+const eventsToSave = ['DeviceCreated', 'DevicePropertyUpdated', 'DeviceTransfered', 'DeviceSigned', 'SignatureRevoked'];
+
+class ManageDevice extends Component {
+  constructor(props) {
+    super(props);
+
+    this.state = {
+      deviceId: this.props.match.params.deviceId,
+      loading: true,
+      showError: false,
+      showEditIdentifier: false,
+      showEditMetadata: false,
+      showEditFirmware: false,
+      showEditOwner: false
+    }
+
+    this.commonChange = this.commonChange.bind(this);
+    this.watchForChanges = this.watchForChanges.bind(this);
+    this.updateDeviceData = this.updateDeviceData.bind(this);
+  }
+
+  componentWillReceiveProps({ match }) {
+    this.setState({ 
+      ...this.state,
+      showError: false,
+      deviceId: match.params.deviceId
+    }, () => this.updateDeviceData());
+  }
+
+  async componentWillMount() {
+    try {
+      let web3 = (await getWeb3).web3;
+      let instance = await DeviceManager;
+
+      this.setState({
+        web3,
+        instance
+      });
+
+      this.updateDeviceData();
+    } catch (error) {
+      console.log(error);
+      //message.error(error.message);
+      this.setState({
+        loading: false,
+        showError: true
+      })
+    }
+  }
+
+  async updateDeviceData() {
+    try {
+      const { instance, deviceId } = this.state;
+      let device = await instance.devices(deviceId);
+      let signatureCount = await instance.deviceSignatureCount(deviceId);
+      let allEvents = instance.allEvents({ fromBlock: 0, toBlock: 'latest' });
+      allEvents.get((error, logs) => {
+        let filteredData = logs.filter(el => eventsToSave.includes(el.event) && el.args.deviceId.toNumber() === parseInt(deviceId, 10));
+        if (!error) {
+          this.setState({
+            data: filteredData,
+            loading: false,
+            owner: device[0],
+            identifier: device[1],
+            metadataHash: device[2],
+            firmwareHash: device[3],
+            signatureCount: signatureCount.toNumber()
+          })
+        }
+
+        let { identifier, metadataHash, firmwareHash, owner } = this.state;
+        this.setState({
+          identifierNew: identifier,
+          metadataHashNew: metadataHash,
+          firmwareHashNew: firmwareHash,
+          ownerNew: owner
+        })
+      });
+    } catch (error) {
+      console.log(error);
+      //message.error(error.message);
+      this.setState({
+        loading: false,
+        showError: true
+      })
+    }
+  }
+
+  toggleEdit(property) {
+    const { showEditFirmware, showEditIdentifier, showEditMetadata, showEditOwner } = this.state;
+
+    switch (property) {
+      case 'identifier':
+        this.setState({
+          showEditIdentifier: !showEditIdentifier
+        })
+        break;
+      case 'metadata':
+        this.setState({
+          showEditMetadata: !showEditMetadata
+        })
+        break;
+      case 'firmware':
+        this.setState({
+          showEditFirmware: !showEditFirmware
+        })
+        break;
+      case 'transfer':
+        this.setState({
+          showEditOwner: !showEditOwner
+        })
+        break;
+      default:
+    }
+  }
+
+  watchForChanges(property) {
+    let filter = this.state.web3.eth.filter('latest', (error, result) => {
+      if (!error) {
+        openNotificationWithIcon('success', 'Transaction mined', `Property ${property} has been updated.`);
+        this.state.filter.stopWatching();
+        this.updateDeviceData();
+      } else {
+        console.error(error);
+      }
+    });
+
+    this.setState({
+      filter
+    })
+  }
+
+  async saveData(property) {
+    const { instance, deviceId, identifier, identifierNew, metadataHash, metadataHashNew, firmwareHash, firmwareHashNew, owner, ownerNew } = this.state;
+
+    try {
+      switch (property) {
+        case 'identifier':
+          if (identifier !== identifierNew) {
+            await instance.updateIdentifier(deviceId, addHexPrefix(identifierNew), { from: getDefaultAccount() });
+            this.watchForChanges(property);
+            openNotificationWithIcon('info', 'Transaction sent', 'Once mined, identifier for this device will be updated.');
+            this.setState({
+              loading: true,
+            });
+          }
+          break;
+        case 'metadata':
+          if (metadataHash !== metadataHashNew) {
+            await instance.updateMetadataHash(deviceId, addHexPrefix(metadataHashNew), { from: getDefaultAccount() });
+            this.watchForChanges(property + ' hash');
+            openNotificationWithIcon('info', 'Transaction sent', 'Once mined, metadata hash for this device will be updated.');
+            this.setState({
+              loading: true,
+            });
+          }
+          break;
+        case 'firmware':
+          if (firmwareHash !== firmwareHashNew) {
+            await instance.updateFirmwareHash(deviceId, addHexPrefix(firmwareHashNew), { from: getDefaultAccount() });
+            this.watchForChanges(property + ' hash');
+            openNotificationWithIcon('info', 'Transaction sent', 'Once mined, firmware hash for this device will be updated.');
+            this.setState({
+              loading: true,
+            });
+          }
+          break;
+        case 'transfer':
+          if (owner !== ownerNew) {
+            await instance.transferDevice(deviceId, addHexPrefix(ownerNew), { from: getDefaultAccount() });
+            this.watchForChanges('owner');
+            openNotificationWithIcon('info', 'Transaction sent', 'Once mined, owner for this device will be updated.');
+            this.setState({
+              loading: true,
+            });
+          }
+          break;
+        default:
+      }
+
+      this.toggleEdit(property);
+    } catch (error) {
+      console.log(error);
+      message.error(error.message);
+      this.toggleEdit(property);
+    }
+
+  }
+
+  commonChange(e) {
+    this.setState({
+      [e.target.name]: e.target.value
+    });
+  }
+
+  render() {
+    const { web3, loading, showError, owner, identifier, metadataHash, firmwareHash,  signatureCount, showEditFirmware, showEditIdentifier, showEditMetadata, showEditOwner } = this.state;
+
+    let identifierContent = () => {
+      if (showEditIdentifier) {
+        return (
+          <div>
+            <Input name="identifierNew" value={this.state.identifierNew} onChange={this.commonChange} maxLength="66" />
+            <Button type="primary" style={{ marginTop: '10px' }} onClick={() => this.saveData('identifier')}>Save</Button>
+          </div>
+        )
+      }
+      return (
+        <div>
+          Identifier {identifier}&nbsp;
+          {owner === getDefaultAccount() &&
+            <a><Icon type="edit" onClick={() => this.toggleEdit('identifier')} /></a>
+          }
+        </div>
+      )
+    }
+
+    let metadataContent = () => {
+      if (showEditMetadata) {
+        return (
+          <div>
+            <Input name="metadataHashNew" value={this.state.metadataHashNew} onChange={this.commonChange} maxLength="66" />
+            <Button type="primary" style={{ marginTop: '10px' }} onClick={() => this.saveData('metadata')}>Save</Button>
+          </div>
+        )
+      }
+      return (
+        <div>
+          Metadata hash {metadataHash.length > 0 ? metadataHash : 'empty'}&nbsp;
+          {owner === getDefaultAccount() &&
+            <a><Icon type="edit" onClick={() => this.toggleEdit('metadata')} /></a>
+          }
+        </div>
+      )
+    }
+
+    let firmwareContent = () => {
+      if (showEditFirmware) {
+        return (
+          <div>
+            <Input name="firmwareHashNew" value={this.state.firmwareHashNew} onChange={this.commonChange} maxLength="66" />
+            <Button type="primary" style={{ marginTop: '10px' }} onClick={() => this.saveData('firmware')}>Save</Button>
+          </div>
+        )
+      }
+      return (
+        <div>
+          Firmware hash {firmwareHash.length > 0 ? firmwareHash : 'empty'}&nbsp;
+          {owner === getDefaultAccount() &&
+            <a><Icon type="edit" onClick={() => this.toggleEdit('firmware')} /></a>
+          }
+        </div>
+      )
+    }
+
+    let transferContent = () => {
+      if (showEditOwner) {
+        return (
+          <div>
+            <Input name="ownerNew" value={this.state.ownerNew} onChange={this.commonChange} maxLength="66" />
+            <Button type="primary" style={{ marginTop: '10px' }} onClick={() => this.saveData('transfer')}>Save</Button>
+          </div>
+        )
+      }
+      return (
+        <div>
+          {owner === getDefaultAccount() &&
+            <Button type="dashed" onClick={() => this.toggleEdit('transfer')}> Transfer ownership</Button>
+          }
+          {owner !== getDefaultAccount() &&
+            <div>
+              Owned by <Link to={"/lookup-entity/" + owner}><Tag>{owner}</Tag></Link>
+            </div>
+          }
+        </div>
+      )
+    }
+
+    return (
+      <div>
+        <Spin spinning={loading} className="loading-spin">
+          {loading === false && showError === false && typeof metadataHash !== 'undefined' &&
+            <div>
+              <h3><div style={{ marginBottom: '20px' }}>{identifierContent()}</div></h3>
+              <Divider />
+              <div style={{ marginBottom: '20px' }}>{metadataContent()}</div>
+              <div style={{ marginBottom: '20px' }}>{firmwareContent()}</div>
+              {transferContent()}
+              <Divider />
+              {signatureCount > 0 &&
+              <div>
+              <div>This device has <strong>{signatureCount}</strong> active signature(s). Devices that have been signed can't be updated.</div>
+              <Divider />
+              </div>
+              }
+              <Card title={'Historical events for device (oldest to newest)'}>
+                {this.state.data.length !== 0 ?
+                  <div>
+                    <p style={{ marginBottom: '20px' }}>Events that are filtered are {eventsToSave.join(', ')} </p>
+                    <Timeline style={{ marginTop: '10px' }}>
+                      {this.state.data.map(el => {
+                        if (el.event === 'DeviceCreated')
+                          return <Timeline.Item color='green'>Device created by &nbsp;<Link to={"/lookup-entity/" + el.args.owner}><Tag>{el.args.owner}</Tag></Link>with &nbsp;<Link to={"/manage-device/" + el.args.deviceId.toNumber()}><Tag>ID {el.args.deviceId.toNumber()}</Tag></Link>, identifier <code>{el.args.identifier}</code>, metadata hash <code>{el.args.metadataHash}</code> and firmware hash <code>{el.args.firmwareHash}</code></Timeline.Item>
+                        if (el.event === 'DevicePropertyUpdated')
+                          return <Timeline.Item>Property {web3.toUtf8(el.args.property)} updated to <code>{el.args.newValue}</code></Timeline.Item>
+                        if (el.event === 'DeviceTransfered')
+                          return <Timeline.Item color='orange'>Device transfered to &nbsp;<Link to={"/lookup-entity/" + el.args.newOwner}><Tag>{el.args.newOwner}</Tag></Link></Timeline.Item>
+                        if (el.event === 'DeviceSigned')
+                          return <Timeline.Item color='purple'>Signature with  &nbsp;<Link to={"/check-signature/" + el.args.signatureId.toNumber()}><Tag>ID {el.args.signatureId.toNumber()}</Tag></Link>created by {el.args.signer}</Timeline.Item>  
+                        if (el.event === 'SignatureRevoked')
+                          return <Timeline.Item color='purple'>Signature with  &nbsp;<Link to={"/check-signature/" + el.args.signatureId.toNumber()}><Tag>ID {el.args.signatureId.toNumber()}</Tag></Link>revoked</Timeline.Item>  
+                        else
+                          return null
+                      })}
+                    </Timeline>
+                  </div>
+                  :
+                  <p><em>empty</em></p>
+                }
+              </Card>
+            </div>
+          }
+          {/*
+          {loading === false && owner !== getDefaultAccount() &&
+            <Alert message="You don't own this device." type="error" showIcon />
+          }
+          */}
+          {loading === false && showError &&
+            <Alert
+              message="Error"
+              description="Error loading device: invalid ID format or device doesn't exist."
+              type="error"
+              showIcon
+            />
+          }
+        </Spin >
+      </div>
+    );
+  }
+}
+
+export default ManageDevice;

frontend/src/components/ManageDevices.js

@@ -0,0 +1,78 @@
+import DeviceManager, { getDefaultAccount } from '../DeviceManager';
+
+import React, { Component } from 'react';
+import { Spin, List, message } from 'antd';
+import { Link } from 'react-router-dom';
+
+class ManageDevices extends Component {
+  constructor(props) {
+    super(props);
+    this.state = {
+      loading: true,
+      instance: null,
+      devices: []
+    }
+  }
+
+  async componentDidMount() {
+    try {
+      let instance = await DeviceManager;
+      let deviceIds = (await instance.getDevicesByOwner(getDefaultAccount())).map(el => el.toNumber());
+
+      let devicePromises = [];
+      for (let deviceId of deviceIds) {
+        let devicePromise = instance.devices(deviceId);
+        devicePromises.push(devicePromise);
+      }
+
+      let devices = await Promise.all(devicePromises);
+
+      this.setState({
+        instance,
+        devices,
+        deviceIds,
+        loading: false
+      });
+    } catch (error) {
+      console.log(error);
+      message.error(error.message);
+    }
+  }
+
+  render() {
+    const { devices, loading } = this.state;
+
+    return (
+      <div>
+        <Spin spinning={loading} className="loading-spin">
+          {devices.length > 0 && !loading &&
+            <div>
+              <p>
+                Below you can find your devices. Click to see more details and manage.
+              </p>
+              <List
+                bordered={true}
+                itemLayout="horizontal"
+                dataSource={devices}
+                renderItem={(device, index) => (
+                  <List.Item>
+                    <List.Item.Meta
+                      /*avatar={<Icon type="profile" style={{ fontSize: 36 }} />}*/
+                      title={<Link to={`/manage-device/${this.state.deviceIds[index]}`}>{`Device ID ${this.state.deviceIds[index]}`}</Link>}
+                      description={`Identifier ${device[1]}`}
+                    />
+                  </List.Item>
+                )}
+              />
+            </div>
+          }
+          {devices.length === 0 && !loading &&
+            <p>You don't have any devices registered.</p>
+          }
+        </Spin>
+      </div>
+    )
+  }
+}
+
+export default ManageDevices;

frontend/src/components/RegisterDevice.css

@@ -0,0 +1,28 @@
+.steps-content {
+  margin-top: 16px;
+  border: 1px dashed #e9e9e9;
+  border-radius: 6px;
+  background-color: #fafafa;
+  padding: 80px 40px;
+}
+  
+.steps-action {
+  margin-top: 24px;
+}
+
+.dynamic-delete-button {
+  cursor: pointer;
+  position: relative;
+  top: 4px;
+  font-size: 24px;
+  color: #999;
+  transition: all .3s;
+  margin-left: 8px;
+}
+.dynamic-delete-button:hover {
+  color: #777;
+}
+.dynamic-delete-button[disabled] {
+  cursor: not-allowed;
+  opacity: 0.5;
+}

frontend/src/components/RegisterDevice.js

@@ -0,0 +1,526 @@
+import getWeb3 from '../utils/web3';
+import DeviceManager, { getDefaultAccount } from '../DeviceManager';
+
+import elliptic from 'elliptic';
+import ethWallet from 'ethereumjs-wallet';
+import { sha3, addHexPrefix, setLengthLeft } from 'ethereumjs-util';
+import { merkleRoot } from 'merkle-tree-solidity';
+
+import React, { Component } from 'react';
+import './RegisterDevice.css';
+
+import { Steps, Button, Input, Card, Spin, Alert, Divider, Form, Icon, Dropdown, Menu, message, notification } from 'antd';
+
+const Step = Steps.Step;
+const { Meta } = Card;
+const EC = elliptic.ec;
+const FormItem = Form.Item;
+
+const steps = [{
+  title: 'Identifier',
+}, {
+  title: 'Metadata',
+}, {
+  title: 'Firmware',
+}, {
+  title: 'Confirm',
+}];
+
+const openNotificationWithIcon = (type, message, description) => {
+  notification[type]({
+    message,
+    description
+  });
+};
+
+class RegisterDevice extends Component {
+  constructor(props) {
+    super(props);
+    this.state = this.getInitialState();
+  }
+
+  getInitialState() {
+    return {
+      loading: false,
+      current: 0,
+      identifier: '',
+      metadataHash: '',
+      firmwareHash: '',
+      showIdentifierInfo: false,
+      publicKey: '',
+      privateKey: '',
+      address: '',
+      metadata: [{ value: '' }],
+      firmware: '',
+      curve: '',
+      deviceId: '',
+    };
+  }
+
+  reset() {
+    this.setState(this.getInitialState());
+  }
+
+  async componentWillMount() {
+    try {
+      let results = await getWeb3;
+
+      this.setState({
+        web3: results.web3,
+      });
+    } catch (error) {
+      console.log(error);
+      message.error(error.message);
+    }
+  }
+
+  async watchForChanges(txHash) {
+    let instance = await DeviceManager;
+    let deviceCreatedEvent = instance.DeviceCreated()
+
+    deviceCreatedEvent.watch((error, result) => {
+      if (!error) {
+        if (result.transactionHash === txHash) {
+          openNotificationWithIcon('success', 'Transaction mined', 'Your device has been registered.');
+          this.state.deviceCreatedEvent.stopWatching();
+          this.setState({
+            loading: false,
+            deviceId: result.args.deviceId.toNumber()
+          })
+          this.next();
+        }
+      } else {
+        console.error(error);
+      }
+    });
+
+    this.setState({
+      deviceCreatedEvent
+    })
+  }
+
+  next() {
+    const { current, identifier/*, metadataHash, firmwareHash*/ } = this.state;
+
+    if ((current === 0) && (identifier === null || identifier === '')) {
+      message.error('Invalid identifier: can\'t be empty');
+      //} else if ((current === 1) && (metadataHash === null || metadataHash === '')) {
+      //  message.error('Invalid metadata hash.');
+      //} else if ((current === 2) && (firmwareHash === null || firmwareHash === '')) {
+      //  message.error('Invalid firmware hash.');
+    } else {
+      this.setState(prevState => ({ current: prevState.current + 1 }));
+    }
+  }
+  prev() {
+    const current = this.state.current - 1;
+    this.setState({ current });
+  }
+
+  gotoStep(i) {
+    this.setState({ current: i });
+  }
+
+  handleChange(e) {
+    this.setState({
+      [e.target.name]: e.target.value,
+    });
+
+    if (this.state.current === 0) {
+      this.setState({
+        showIdentifierInfo: false
+      });
+    }
+
+    if (this.state.current === 0 && e.target.name === 'identifier') {
+      this.setState({
+        showIdentifierInfo: false,
+        publicKey: '',
+        privateKey: '',
+        address: '',
+        curve: ''
+      });
+    }
+
+    if (this.state.current === 1 && e.target.name === 'metadataHash') {
+      this.setState({
+        metadata: [{ value: '' }]
+      });
+    }
+
+    if (this.state.current === 2 && e.target.name === 'firmwareHash') {
+      this.setState({
+        firmware: ''
+      });
+    }
+  }
+
+  generateEthWallet() {
+    console.log(`Generating new Ethereum wallet`);
+    const newWallet = ethWallet.generate();
+
+    let publicKey = newWallet.getPublicKey().toString('hex');
+    let privateKey = newWallet.getPrivateKey().toString('hex');
+    let address = newWallet.getAddressString();
+
+    console.log(`Private key: ${privateKey}`);
+    console.log(`Public key: ${publicKey}`);
+    console.log(`Address: ${address}`);
+
+    this.setState({
+      identifier: address,
+      showIdentifierInfo: true,
+      address,
+      publicKey,
+      privateKey,
+      curve: 'secp256k1'
+    })
+  }
+
+  generateEcKeyPair(curve) {
+    let ec = new EC(curve);
+    console.log(`Generating new ${curve} key pair`);
+    let keyPair = ec.genKeyPair();
+
+    let publicKey = keyPair.getPublic(true, 'hex');
+    let privateKey = keyPair.getPrivate('hex');
+
+    console.log(`Private key: ${privateKey}`);
+    console.log(`Public key compressed: ${publicKey}`);
+    console.log(`Public key uncompressed: ${keyPair.getPublic().encode('hex')}`);
+
+    this.setState({
+      identifier: publicKey,
+      showIdentifierInfo: true,
+      address: '',
+      publicKey,
+      privateKey,
+      curve
+    })
+  }
+
+  calculateMetadataHash() {
+    let elements = this.state.metadata.map(el => sha3(el.value));
+    console.log(`Generating Merkle root hash`);
+
+    let metadataRootSha3 = merkleRoot(elements);
+    console.log(`Merkle root hash ${metadataRootSha3.toString('hex')}`);
+
+    this.setState({
+      metadataHash: metadataRootSha3.toString('hex')
+    })
+  }
+
+  calculateFirmwareHash() {
+    let firmwareHash = sha3(this.state.firmware);
+
+    this.setState({
+      firmwareHash: firmwareHash.toString('hex')
+    })
+  }
+
+  removeMetadataField(k) {
+    const { metadata } = this.state;
+    metadata.splice(k, 1);
+    this.setState({
+      metadata
+    })
+  }
+
+  addMetadataField() {
+    const { metadata } = this.state;
+    metadata.push({ value: '' });
+    this.setState({
+      metadata
+    });
+  }
+
+  handleMetadataChange(e, index) {
+    const { metadata } = this.state;
+    metadata[index].value = e.target.value;
+
+    this.setState({
+      metadata
+    });
+  }
+
+  downloadConfiguration() {
+    const { identifier, metadataHash, firmwareHash, metadata, firmware, address, publicKey, privateKey, curve, deviceId } = this.state;
+
+    const configuration = {
+      identifier,
+      metadataHash,
+      firmwareHash,
+    };
+
+    if (metadata.length > 0 && metadata[0].value !== '' && metadataHash !== '') {
+      configuration.metadata = metadata.map(el => el.value);
+    }
+
+    if (firmware !== '' && firmwareHash !== '') {
+      configuration.firmware = firmware;
+    }
+
+    if (address !== '') {
+      configuration.address = address;
+    }
+
+    if (publicKey !== '') {
+      configuration.publicKey = publicKey;
+    }
+
+    if (privateKey !== '') {
+      configuration.privateKey = privateKey;
+    }
+
+    if (curve !== '') {
+      configuration.curve = curve;
+    }
+
+    if (deviceId !== '') {
+      configuration.deviceId = deviceId;
+    }
+
+    let configurationJson = JSON.stringify(configuration);
+
+    let element = document.createElement("a");
+    let file = new Blob([configurationJson], { type: 'text/json' });
+    element.href = URL.createObjectURL(file);
+    element.download = `device_${deviceId}.json`;
+    element.click();
+  }
+
+  onCurveSelect({ key }) {
+    this.generateEcKeyPair(key);
+  };
+
+  getContentForStep(step) {
+    const { identifier, metadataHash, firmwareHash, metadata, firmware } = this.state;
+
+    // Identifier
+    if (step === 0) {
+      const curves = ['p224', 'curve25519'];
+      const ecMenu = (
+        <Menu onClick={(e) => this.onCurveSelect(e)}>
+          {curves.map(curve => <Menu.Item key={curve}>{curve}</Menu.Item>)}
+        </Menu>
+      );
+      return (
+        <div>
+          <p>
+            <strong>Unique device identifier</strong> is a public key or a fingerprint of RSA/ECC public key. It can also be an Ethereum address (recommended).
+          </p>
+          <Input
+            placeholder="Identifier e.g. Ethereum address"
+            style={{ maxWidth: '800px' }}
+            value={identifier}
+            name="identifier"
+            maxLength="66"
+            onChange={(e) => this.handleChange(e)}
+          />
+          <br /><br />
+          <Button.Group size="large">
+            <Button type="primary" onClick={() => this.generateEthWallet()}>Generate Ethereum wallet</Button>
+            <Dropdown overlay={ecMenu}>
+              <Button type="primary">
+                Generate elliptic curve key pair
+              </Button>
+            </Dropdown>
+          </Button.Group>
+          {this.state.showIdentifierInfo ?
+            <div>
+              <br />
+              <Alert message="You will be given private key and device configuration on the last step." type="info" showIcon />
+            </div> : null}
+        </div>
+      );
+    }
+
+    // Metadata hash
+    if (step === 1) {
+      return (
+        <div>
+          <p>
+            <strong>Metadash hash</strong> is Merkle root hash of device information or just a hash of any data.
+          </p>
+          <Input
+            placeholder="Metadata hash"
+            style={{ maxWidth: '800px' }}
+            value={metadataHash}
+            name="metadataHash"
+            maxLength="66"
+            onChange={(e) => this.handleChange(e)}
+          />
+          <Divider />
+          <p>
+            If you already don't have one, you can use inputs below to generate SHA-3 (Keccak) hash. With multiple fields, Merkle tree will be used.
+          </p>
+          <br />
+          <Form>
+            {metadata.map((key, index) => {
+              return (
+                <FormItem>
+                  <Input
+                    placeholder="Some information"
+                    style={{ width: '60%' }}
+                    value={key.value}
+                    maxLength="66"
+                    onChange={(e) => this.handleMetadataChange(e, index)}
+                  />
+                  {metadata.length > 1 ? (
+                    <Icon
+                      className="dynamic-delete-button"
+                      type="minus-circle-o"
+                      disabled={metadata.length === 1}
+                      onClick={() => this.removeMetadataField(index)}
+                    />
+                  ) : null}
+                </FormItem>
+              )
+            })
+            }
+            <FormItem>
+              <Button type="dashed" onClick={() => this.addMetadataField()} style={{ width: '60%' }}>
+                <Icon type="plus" /> Add field
+              </Button>
+            </FormItem>
+            <FormItem>
+              <Button type="primary" onClick={() => this.calculateMetadataHash()}>Generate</Button>
+            </FormItem>
+          </Form>
+        </div>
+      );
+    }
+
+    // Firmware hash
+    if (step === 2) {
+      return (
+        <div>
+          <p>
+            <strong>Firmware hash</strong> is a hash of actual firmware hash. Actual firmware hash is not supposed to be stored.
+        </p>
+          <Input
+            placeholder="Firmware hash"
+            style={{ maxWidth: '800px' }}
+            value={firmwareHash}
+            name="firmwareHash"
+            maxLength="66"
+            onChange={(e) => this.handleChange(e)}
+          />
+          <Divider />
+          <p>
+            You can use input to generate SHA-3 (Keccak) hash of any data.
+          </p>
+          <br />
+          <Input
+            placeholder="Some data"
+            style={{ width: '60%' }}
+            value={firmware}
+            name="firmware"
+            onChange={(e) => this.handleChange(e)}
+          />
+          <br />
+          <br />
+          <Button type="primary" onClick={() => this.calculateFirmwareHash()}>Generate</Button>
+        </div>
+      );
+    }
+
+    // Overview/confirm
+    if (step === 3) {
+      return (
+        <div>
+          <Card title={<div>Identifier  {identifier} <a><Icon type="edit" onClick={() => this.gotoStep(0)} /></a></div>} bordered={false}>
+            <Meta
+              title={<div>Metadata hash {metadataHash.length > 0 ? metadataHash : 'empty'} <a><Icon type="edit" onClick={() => this.gotoStep(1)} /></a></div>}
+              description={<div>Firmware hash {firmwareHash.length > 0 ? firmwareHash : 'empty'} <a><Icon type="edit" onClick={() => this.gotoStep(2)} /></a></div>}
+            />
+          </Card>
+        </div >
+      );
+    }
+
+    // Configuration
+    if (step === 4) {
+      return (
+        <div style={{ textAlign: 'center' }}>
+          <Icon type="check-circle-o" style={{ fontSize: 46 }} />
+          <br /><br />
+          <p>
+            Click below to download device configuration.
+          </p>
+          <br />
+          <Button type="primary" onClick={() => this.downloadConfiguration()}>Download</Button>
+        </div>
+      );
+    }
+  }
+
+  async createDevice() {
+    const { identifier, metadataHash, firmwareHash, address } = this.state;
+    try {
+      let instance = await DeviceManager;
+
+      let identifierToSave = identifier;
+      if (address !== '') {
+        let addressToPad = address;
+        if (address.startsWith('0x')) {
+          addressToPad = addressToPad.substring(2);
+        }
+        identifierToSave = setLengthLeft(Buffer.from(addressToPad, 'hex'), 32).toString('hex');
+      }
+
+      let result = await instance.createDevice(addHexPrefix(identifierToSave), addHexPrefix(metadataHash), addHexPrefix(firmwareHash), { from: getDefaultAccount() });
+      await this.watchForChanges(result.tx);
+      openNotificationWithIcon('info', 'Transaction sent', 'Once mined, your device will be registered.');
+      this.setState({
+        loading: true
+      });
+    } catch (error) {
+      console.log(error);
+      message.error(error.message);
+    }
+  }
+
+  render() {
+    const { current } = this.state;
+    return (
+      <div>
+        <Spin spinning={this.state.loading} className="loading-spin">
+          <Steps current={current}>
+            {steps.map(item => <Step key={item.title} title={item.title} />)}
+          </Steps>
+          <div className="steps-content">{this.getContentForStep(current)}</div>
+          <div className="steps-action">
+            {
+              current < steps.length - 1
+              && <Button type="primary" onClick={() => this.next()}>Next</Button>
+            }
+            {
+              current === steps.length - 1
+              && <Button type="primary" onClick={() => this.createDevice()}>Register</Button>
+            }
+            {
+              current > 0 && current !== 4
+              && (
+                <Button style={{ marginLeft: 8 }} onClick={() => this.prev()}>
+                  Previous
+            </Button>
+              )
+            }
+            {
+              current === 4
+              && (
+                <Button type="primary" onClick={() => this.reset()}>
+                  Reset
+            </Button>
+              )
+            }
+          </div>
+        </Spin>
+      </div>
+    );
+  }
+}
+
+export default RegisterDevice;

frontend/src/index.js

@@ -0,0 +1,7 @@
+import React from 'react';
+import ReactDOM from 'react-dom';
+import App from './App';
+import registerServiceWorker from './registerServiceWorker';
+
+ReactDOM.render(<App />, document.getElementById('root'));
+registerServiceWorker();

frontend/src/registerServiceWorker.js

@@ -0,0 +1,117 @@
+// In production, we register a service worker to serve assets from local cache.
+
+// This lets the app load faster on subsequent visits in production, and gives
+// it offline capabilities. However, it also means that developers (and users)
+// will only see deployed updates on the "N+1" visit to a page, since previously
+// cached resources are updated in the background.
+
+// To learn more about the benefits of this model, read https://goo.gl/KwvDNy.
+// This link also includes instructions on opting out of this behavior.
+
+const isLocalhost = Boolean(
+  window.location.hostname === 'localhost' ||
+    // [::1] is the IPv6 localhost address.
+    window.location.hostname === '[::1]' ||
+    // 127.0.0.1/8 is considered localhost for IPv4.
+    window.location.hostname.match(
+      /^127(?:\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)){3}$/
+    )
+);
+
+export default function register() {
+  if (process.env.NODE_ENV === 'production' && 'serviceWorker' in navigator) {
+    // The URL constructor is available in all browsers that support SW.
+    const publicUrl = new URL(process.env.PUBLIC_URL, window.location);
+    if (publicUrl.origin !== window.location.origin) {
+      // Our service worker won't work if PUBLIC_URL is on a different origin
+      // from what our page is served on. This might happen if a CDN is used to
+      // serve assets; see https://github.com/facebookincubator/create-react-app/issues/2374
+      return;
+    }
+
+    window.addEventListener('load', () => {
+      const swUrl = `${process.env.PUBLIC_URL}/service-worker.js`;
+
+      if (isLocalhost) {
+        // This is running on localhost. Lets check if a service worker still exists or not.
+        checkValidServiceWorker(swUrl);
+
+        // Add some additional logging to localhost, pointing developers to the
+        // service worker/PWA documentation.
+        navigator.serviceWorker.ready.then(() => {
+          console.log(
+            'This web app is being served cache-first by a service ' +
+              'worker. To learn more, visit https://goo.gl/SC7cgQ'
+          );
+        });
+      } else {
+        // Is not local host. Just register service worker
+        registerValidSW(swUrl);
+      }
+    });
+  }
+}
+
+function registerValidSW(swUrl) {
+  navigator.serviceWorker
+    .register(swUrl)
+    .then(registration => {
+      registration.onupdatefound = () => {
+        const installingWorker = registration.installing;
+        installingWorker.onstatechange = () => {
+          if (installingWorker.state === 'installed') {
+            if (navigator.serviceWorker.controller) {
+              // At this point, the old content will have been purged and
+              // the fresh content will have been added to the cache.
+              // It's the perfect time to display a "New content is
+              // available; please refresh." message in your web app.
+              console.log('New content is available; please refresh.');
+            } else {
+              // At this point, everything has been precached.
+              // It's the perfect time to display a
+              // "Content is cached for offline use." message.
+              console.log('Content is cached for offline use.');
+            }
+          }
+        };
+      };
+    })
+    .catch(error => {
+      console.error('Error during service worker registration:', error);
+    });
+}
+
+function checkValidServiceWorker(swUrl) {
+  // Check if the service worker can be found. If it can't reload the page.
+  fetch(swUrl)
+    .then(response => {
+      // Ensure service worker exists, and that we really are getting a JS file.
+      if (
+        response.status === 404 ||
+        response.headers.get('content-type').indexOf('javascript') === -1
+      ) {
+        // No service worker found. Probably a different app. Reload the page.
+        navigator.serviceWorker.ready.then(registration => {
+          registration.unregister().then(() => {
+            window.location.reload();
+          });
+        });
+      } else {
+        // Service worker found. Proceed as normal.
+        registerValidSW(swUrl);
+      }
+    })
+    .catch(() => {
+      console.log(
+        'No internet connection found. App is running in offline mode.'
+      );
+    });
+}
+
+export function unregister() {
+  if ('serviceWorker' in navigator) {
+    navigator.serviceWorker.ready.then(registration => {
+      registration.unregister();
+    });
+  }
+}

frontend/src/utils/web3.js

@@ -0,0 +1,35 @@
+import Web3 from 'web3'
+
+let getWeb3 = new Promise(function (resolve, reject) {
+  window.addEventListener('load', function () {
+    let results;
+    let web3 = window.web3;
+
+    // Checking if Web3 has been injected by the browser (Mist/MetaMask)
+    if (typeof web3 !== 'undefined') {
+      // Use Mist/MetaMask's provider.
+      web3 = new Web3(web3.currentProvider);
+
+      results = {
+        web3: web3
+      };
+
+      console.log('Injected web3 detected.');
+      resolve(results)
+    } else {
+      let provider = new Web3.providers.HttpProvider('http://127.0.0.1:8545');
+      web3 = new Web3(provider);
+
+      results = {
+        web3: web3
+      };
+
+      console.log('No web3 instance injected, using Local web3.');
+
+      // should be resolved, leave reject for dev as there should always be metamask installed
+      reject(results);
+    }
+  })
+})
+
+export default getWeb3;

migrations/1_initial_migration.js

@@ -0,0 +1,5 @@
+var Migrations = artifacts.require("./Migrations.sol");
+
+module.exports = function(deployer) {
+  deployer.deploy(Migrations);
+};

migrations/2_deploy_contracts.js

@@ -0,0 +1,5 @@
+var DeviceManager = artifacts.require("./DeviceManager.sol");
+
+module.exports = function(deployer) {
+  deployer.deploy(DeviceManager);
+};

package.json

@@ -0,0 +1,5 @@
+{
+  "dependencies": {
+    "truffle": "^5.11.5"
+  }
+}

simulations/.gitignore

@@ -0,0 +1,2 @@
+node_modules
+config*.json

simulations/device.js

@@ -0,0 +1,74 @@
+const request = require('request');
+const { hashPersonalMessage, ecsign, ecrecover, toRpcSig, fromRpcSig, keccak256, addHexPrefix, sha3 } = require('ethereumjs-util');
+const { default: MerkleTree } = require('merkle-tree-solidity');
+
+const args = process.argv.slice(2);
+const [configPath] = args;
+
+// Configuration file downloaded after registering device
+const deviceConfig = require(configPath);
+
+const hashMessageEth = message => hashPersonalMessage(Buffer.from(message));
+
+const signMessageEth = (message, privateKey) => {
+  let messageHash = hashMessageEth(message);
+  //console.log('Message hash: ' + messageHash.toString('hex'));
+  let { v, r, s } = ecsign(messageHash, privateKey);
+  let rpcSignature = toRpcSig(v, r, s);
+  //console.log('Message signature: ' + rpcSignature);
+  return rpcSignature;
+}
+
+const validateSignatureEth = (messageHash, signature, publicKey, address) => {
+  signature = fromRpcSig(signature);
+  let recoveredPublicKey = ecrecover(messageHash, signature.v, signature.r, signature.s);
+  let recoveredPublicKeyHex = recoveredPublicKey.toString('hex');
+  let recoveredAddress = addHexPrefix(keccak256(recoveredPublicKey).toString('hex').substring(64 - 40));
+  //console.log('Recovered public key: ' + recoveredPublicKeyHex);
+  //console.log('Recovered address: ' + recoveredAddress);
+  if (recoveredPublicKeyHex === publicKey && recoveredAddress === address) return true;
+  return false;
+}
+
+// Gather data and sign
+const privateKey = Buffer.from(deviceConfig.privateKey, 'hex');
+
+let message = 'test';
+let signature = signMessageEth(message, privateKey);
+
+// Validate signature
+if (!validateSignatureEth(hashMessageEth(message), signature, deviceConfig.publicKey, deviceConfig.address)) {
+  process.exit();
+}
+
+// Construct Merkle tree
+const metadataHashes = deviceConfig.metadata.map(el => sha3(el));
+const merkleTree = new MerkleTree(metadataHashes);
+
+// Index of metadata element to send
+const elementToSend = 0;
+
+// Generate proof
+let proof = merkleTree.getProof(metadataHashes[elementToSend]);
+proof = proof.map(el => addHexPrefix(el.toString('hex')));
+
+// Build payload
+let payload = {
+  deviceId: deviceConfig.deviceId,
+  message,
+  signature: signature,
+  metadata: deviceConfig.metadata[elementToSend],
+  proof,
+  firmware: deviceConfig.firmware,
+  curve: deviceConfig.curve
+}
+
+// Send to platform
+const platformEndpoint = 'http://localhost:1337/receive'
+request.post({ url: platformEndpoint, json: payload }, function (error, response, body) {
+  if (!error) {
+    console.log(body)
+  } else {
+    console.log(error);
+  }
+})

simulations/package.json

@@ -0,0 +1,11 @@
+{
+  "name": "simulations",
+  "version": "0.1.0",
+  "dependencies": {
+    "ethereumjs-util": "5.2.0",
+    "express": "4.16.3",
+    "merkle-tree-solidity": "1.0.8",
+    "request": "2.88.0",
+    "web3": "0.20.6"
+  }
+}

simulations/platform.js

@@ -0,0 +1,49 @@
+const express = require('express');
+const app = express();
+const Web3 = require('web3');
+const { hashPersonalMessage, addHexPrefix, sha3 } = require('ethereumjs-util');
+
+const hashMessageHex = message => addHexPrefix(hashPersonalMessage(Buffer.from(message)).toString('hex'));
+
+app.use(express.json());
+
+const DeviceManagerArtifact = require('../build/contracts/DeviceManager.json');
+let latestNetwork = DeviceManagerArtifact.networks[Object.keys(DeviceManagerArtifact.networks).reduce((res, curr) => curr > res ? curr : res)];
+
+// Connect to local node
+const web3 = new Web3(new Web3.providers.HttpProvider("http://localhost:8545"));
+web3.eth.defaultAccount = web3.eth.accounts[0];
+
+// Instance using ABI and contract address
+const deviceManager = web3.eth.contract(DeviceManagerArtifact.abi).at(latestNetwork.address);
+
+// Receive payload and validate on blockchain
+app.post('/receive', function (req, res) {
+  console.log('received payload: ' + JSON.stringify(req.body));
+
+  // Validate message
+  const { deviceId, message, signature } = req.body;
+  let validMessage = deviceManager.isValidEthMessage(deviceId, hashMessageHex(message), signature);
+  console.log('valid message: ' + validMessage);
+
+  // Validate metadata
+  const { metadata, proof } = req.body;
+  let metadataHash = addHexPrefix(sha3(metadata).toString('hex'));
+  let validMetadata = deviceManager.isValidMetadataMember(deviceId, proof, metadataHash);
+  console.log('valid metadata: ' + validMetadata);
+
+  // Validate firmware
+  const { firmware } = req.body;
+  let firmwareHash = addHexPrefix(sha3(firmware).toString('hex'));
+  let validFirmware = deviceManager.isValidFirmwareHash(deviceId, firmwareHash);
+  console.log('valid firmware: ' + validFirmware);
+
+  // Respond back with status
+  res.send({
+    validMessage,
+    validMetadata,
+    validFirmware
+  });
+})
+
+app.listen(1337, () => console.log('Platform simulation listening on port 1337'));

test/TestDeviceManager.sol

@@ -0,0 +1,39 @@
+pragma solidity ^0.4.24;
+// FIXME - cannot be resolved by truffle
+import "truffle/Assert.sol";
+import "truffle/DeployedAddresses.sol";
+import "../contracts/DeviceManager.sol";
+
+contract TestDeviceManager {
+    DeviceManager deviceManager = DeviceManager(DeployedAddresses.DeviceManager());
+    uint constant createdDeviceId = 0;
+
+    function testCreateDevice() public {
+        uint deviceId = deviceManager.createDevice(
+            sha256("identifier"),
+            sha256("metadata"),
+            sha256("firmware")
+        );
+
+        Assert.equal(deviceId, createdDeviceId, "New device should be recorded with ID of 0.");
+    }
+
+    function testCreatedDeviceOwner() public {
+        address owner;
+        (owner,,,) = deviceManager.devices(createdDeviceId); 
+
+        Assert.equal(owner, this, "Created device should be recorded and owned by this address");
+    }
+
+    function testGetDevicesByOwner() public {
+        uint[] memory deviceIds = deviceManager.getDevicesByOwner(this);
+        uint[] memory expectedIds = new uint[](1);
+        expectedIds[0] = 0;
+
+        Assert.equal(
+            keccak256(abi.encodePacked(deviceIds)), 
+            keccak256(abi.encodePacked(expectedIds)), 
+            "Only one device should have been created owned by this address"
+        );
+    }
+}

truffle-config.js

@@ -0,0 +1,9 @@
+module.exports = {
+  networks: {
+    development: {
+      host: "127.0.0.1",
+      port: 8545,
+      network_id: "*"
+    }
+  }
+};

truffle.js

@@ -0,0 +1,9 @@
+module.exports = {
+  networks: {
+    development: {
+      host: "127.0.0.1",
+      port: 8545,
+      network_id: "*"
+    }
+  }
+};