Move SignTypedData to utils package

3 files changed, 189 insertions, 0 deletions

diff --git a/packages/utils/src/index.ts b/packages/utils/src/index.ts
index 9d01e5bc5..0723e5788 100644
--- a/packages/utils/src/index.ts
+++ b/packages/utils/src/index.ts
@@ -9,3 +9,4 @@ export { abiUtils } from './abi_utils';
 export { NULL_BYTES } from './constants';
 export { errorUtils } from './error_utils';
 export { fetchAsync } from './fetch_async';
+export { signTypedDataUtils } from './sign_typed_data_utils';
diff --git a/packages/utils/src/sign_typed_data_utils.ts b/packages/utils/src/sign_typed_data_utils.ts
new file mode 100644
index 000000000..902d8530c
--- /dev/null
+++ b/packages/utils/src/sign_typed_data_utils.ts
@@ -0,0 +1,81 @@
+import * as ethUtil from 'ethereumjs-util';
+import * as ethers from 'ethers';
+
+export interface EIP712Parameter {
+    name: string;
+    type: string;
+}
+
+export interface EIP712Types {
+    [key: string]: EIP712Parameter[];
+}
+export interface EIP712TypedData {
+    types: EIP712Types;
+    domain: any;
+    message: any;
+    primaryType: string;
+}
+
+export const signTypedDataUtils = {
+    findDependencies(primaryType: string, types: EIP712Types, found: string[] = []): string[] {
+        if (found.includes(primaryType) || types[primaryType] === undefined) {
+            return found;
+        }
+        found.push(primaryType);
+        for (const field of types[primaryType]) {
+            for (const dep of signTypedDataUtils.findDependencies(field.type, types, found)) {
+                if (!found.includes(dep)) {
+                    found.push(dep);
+                }
+            }
+        }
+        return found;
+    },
+    encodeType(primaryType: string, types: EIP712Types): string {
+        let deps = signTypedDataUtils.findDependencies(primaryType, types);
+        deps = deps.filter(d => d !== primaryType);
+        deps = [primaryType].concat(deps.sort());
+        let result = '';
+        for (const dep of deps) {
+            result += `${dep}(${types[dep].map(({ name, type }) => `${type} ${name}`).join(',')})`;
+        }
+        return result;
+    },
+    encodeData(primaryType: string, data: any, types: EIP712Types): string {
+        const encodedTypes = ['bytes32'];
+        const encodedValues = [signTypedDataUtils.typeHash(primaryType, types)];
+        for (const field of types[primaryType]) {
+            let value = data[field.name];
+            if (field.type === 'string' || field.type === 'bytes') {
+                value = ethUtil.sha3(value);
+                encodedTypes.push('bytes32');
+                encodedValues.push(value);
+            } else if (types[field.type] !== undefined) {
+                encodedTypes.push('bytes32');
+                value = ethUtil.sha3(signTypedDataUtils.encodeData(field.type, value, types));
+                encodedValues.push(value);
+            } else if (field.type.lastIndexOf(']') === field.type.length - 1) {
+                throw new Error('Arrays currently unimplemented in encodeData');
+            } else {
+                encodedTypes.push(field.type);
+                encodedValues.push(value);
+            }
+        }
+        return ethers.utils.defaultAbiCoder.encode(encodedTypes, encodedValues);
+    },
+    typeHash(primaryType: string, types: EIP712Types): Buffer {
+        return ethUtil.sha3(signTypedDataUtils.encodeType(primaryType, types));
+    },
+    structHash(primaryType: string, data: any, types: EIP712Types): Buffer {
+        return ethUtil.sha3(signTypedDataUtils.encodeData(primaryType, data, types));
+    },
+    signTypedDataHash(typedData: EIP712TypedData): Buffer {
+        return ethUtil.sha3(
+            Buffer.concat([
+                Buffer.from('1901', 'hex'),
+                signTypedDataUtils.structHash('EIP712Domain', typedData.domain, typedData.types),
+                signTypedDataUtils.structHash(typedData.primaryType, typedData.message, typedData.types),
+            ]),
+        );
+    },
+};
diff --git a/packages/utils/test/sign_typed_data_utils_test.ts b/packages/utils/test/sign_typed_data_utils_test.ts
new file mode 100644
index 000000000..b21ffefa0
--- /dev/null
+++ b/packages/utils/test/sign_typed_data_utils_test.ts
@@ -0,0 +1,107 @@
+import * as chai from 'chai';
+import 'mocha';
+
+import { signTypedDataUtils } from '../src/sign_typed_data_utils';
+
+const expect = chai.expect;
+
+describe('signTypedDataUtils', () => {
+    describe('signTypedDataHash', () => {
+        const signTypedDataHashHex = '0x55eaa6ec02f3224d30873577e9ddd069a288c16d6fb407210eecbc501fa76692';
+        const signTypedData = {
+            types: {
+                EIP712Domain: [
+                    {
+                        name: 'name',
+                        type: 'string',
+                    },
+                    {
+                        name: 'version',
+                        type: 'string',
+                    },
+                    {
+                        name: 'verifyingContract',
+                        type: 'address',
+                    },
+                ],
+                Order: [
+                    {
+                        name: 'makerAddress',
+                        type: 'address',
+                    },
+                    {
+                        name: 'takerAddress',
+                        type: 'address',
+                    },
+                    {
+                        name: 'feeRecipientAddress',
+                        type: 'address',
+                    },
+                    {
+                        name: 'senderAddress',
+                        type: 'address',
+                    },
+                    {
+                        name: 'makerAssetAmount',
+                        type: 'uint256',
+                    },
+                    {
+                        name: 'takerAssetAmount',
+                        type: 'uint256',
+                    },
+                    {
+                        name: 'makerFee',
+                        type: 'uint256',
+                    },
+                    {
+                        name: 'takerFee',
+                        type: 'uint256',
+                    },
+                    {
+                        name: 'expirationTimeSeconds',
+                        type: 'uint256',
+                    },
+                    {
+                        name: 'salt',
+                        type: 'uint256',
+                    },
+                    {
+                        name: 'makerAssetData',
+                        type: 'bytes',
+                    },
+                    {
+                        name: 'takerAssetData',
+                        type: 'bytes',
+                    },
+                ],
+            },
+            domain: {
+                name: '0x Protocol',
+                version: '2',
+                verifyingContract: '0x0000000000000000000000000000000000000000',
+            },
+            message: {
+                makerAddress: '0x0000000000000000000000000000000000000000',
+                takerAddress: '0x0000000000000000000000000000000000000000',
+                makerAssetAmount: '1000000000000000000',
+                takerAssetAmount: '1000000000000000000',
+                expirationTimeSeconds: '12345',
+                makerFee: '0',
+                takerFee: '0',
+                feeRecipientAddress: '0x0000000000000000000000000000000000000000',
+                senderAddress: '0x0000000000000000000000000000000000000000',
+                salt: '12345',
+                makerAssetData: '0x0000000000000000000000000000000000000000',
+                takerAssetData: '0x0000000000000000000000000000000000000000',
+                exchangeAddress: '0x0000000000000000000000000000000000000000',
+            },
+            primaryType: 'Order',
+        };
+        it.only('creates a known hash of the sign typed data', () => {
+            const hash = signTypedDataUtils.signTypedDataHash(signTypedData).toString('hex');
+            const hashHex = `0x${hash}`;
+            expect(hashHex).to.be.eq(signTypedDataHashHex);
+            console.log(hash);
+        });
+    });
+});