ethereum-input-data-decoder - npm Package Compare versions

Comparing version 0.0.3 to 0.0.4

index.js

@@ -1,33 +0,87 @@
-const fs = require('fs');
-const ethabi = require('ethereumjs-abi');
+const fs = require('fs')
+const ethabi = require('ethereumjs-abi')
+const ethers = require('ethers')
 
 class InputDataDecoder {
   constructor(prop) {
-    this.abi = [];
+    this.abi = []
 
     if (typeof prop === `string`) {
-      this.abi = JSON.parse(fs.readFileSync(prop));
+      this.abi = JSON.parse(fs.readFileSync(prop))
     } else if (prop instanceof Object) {
-      this.abi = prop;
+      this.abi = prop
     } else {
-      throw new TypeError(`Must pass ABI array object or file path to constructor`);
+      throw new TypeError(`Must pass ABI array object or file path to constructor`)
     }
   }
 
-  decodeData(data = ``) {
+  decodeConstructor(data) {
+    if (Buffer.isBuffer(data)) {
+      data = data.toString('utf8')
+    }
+
     if (typeof data !== `string`) {
-      data = ``;
+      data = ``
     }
 
-    const dataBuf = new Buffer(data.replace(/^0x/, ``), `hex`);
-    const methodId = dataBuf.slice(0, 4).toString(`hex`);
-    const inputsBuf = dataBuf.slice(4);
+    data = data.trim()
 
+    for (var i = 0; i < this.abi.length; i++) {
+      const obj = this.abi[i]
+      if (obj.type !== 'constructor') {
+        continue
+      }
+
+      const name = obj.name
+      const types = obj.inputs ? obj.inputs.map(x => x.type) : []
+
+      // take last 32 bytes
+      data = data.slice(-256)
+
+      if (data.length !== 256) {
+        throw new Error('fial')
+      }
+
+      if (data.indexOf(`0x`) !== 0) {
+        data = `0x${data}`
+      }
+
+      const inputs = ethers.Interface.decodeParams(types, data)
+
+      return {
+        name,
+        types,
+        inputs
+      }
+    }
+
+    throw new Error('not found')
+  }
+
+  decodeData(data) {
+    if (Buffer.isBuffer(data)) {
+      data = data.toString('utf8')
+    }
+
+    if (typeof data !== `string`) {
+      data = ``
+    }
+
+    data = data.trim()
+
+    try {
+      return this.decodeConstructor(data)
+    } catch(err) { }
+
+    const dataBuf = new Buffer(data.replace(/^0x/, ``), `hex`)
+    const methodId = dataBuf.slice(0, 4).toString(`hex`)
+    const inputsBuf = dataBuf.slice(4)
+
     const result = this.abi.reduce((acc, obj) => {
-      const name = obj.name;
-      const types = obj.inputs ? obj.inputs.map(x => x.type) : [];
-      const hash = ethabi.methodID(name, types).toString(`hex`);
+      const name = obj.name
+      const types = obj.inputs ? obj.inputs.map(x => x.type) : []
+      const hash = ethabi.methodID(name, types).toString(`hex`)
 
       if (hash === methodId) {
-        const inputs = ethabi.rawDecode(types, inputsBuf, []);
+        const inputs = ethabi.rawDecode(types, inputsBuf, [])
 
@@ -41,9 +95,9 @@ return {
 
-      return acc;
-    }, {});
+      return acc
+    }, {})
 
-    return result;
+    return result
   }
 }
 
-module.exports = InputDataDecoder;
+module.exports = InputDataDecoder

package.json

 {
   "name": "ethereum-input-data-decoder",
-  "version": "0.0.3",
+  "version": "0.0.4",
   "description": "Ethereum smart contract transaction input data decoder",
@@ -21,3 +21,4 @@ "main": "index.js",
   "dependencies": {
-    "ethereumjs-abi": "^0.6.4"
+    "ethereumjs-abi": "^0.6.4",
+    "ethers": "^2.1.3"
   },
@@ -24,0 +25,0 @@ "keywords": [

README.md

@@ -80,4 +80,18 @@ # Ethereum input data decoder
 
+## FAQ
+
+- Q: How can I retrieve the ABI?
+
+  - A: You can generate the ABI from the solidity source files using the [Solidity Compiler](http://solidity.readthedocs.io/en/develop/installing-solidity.html).
+
+    ```bash
+    solc --abi MyContract.sol -o build
+    ```
+
+- Q: Can this library decode contract creation input data?
+
+  - A: Yes, it can decode contract creation input data.
+
 ## License
 
 MIT

test/index.js

@@ -7,3 +7,3 @@ const fs = require('fs');
  * Example input data from this transaction
- * https://etherscan.io/tx/0xa6f019f2fc916bd8df607f1c99148ebb06322999ff08bc88927fe8406acae1b2)
+ * https://etherscan.io/tx/0xa6f019f2fc916bd8df607f1c99148ebb06322999ff08bc88927fe8406acae1b2
  */
@@ -54,2 +54,16 @@
   });
-});
+
+  // https://etherscan.io/tx/0xc7add41f6ae5e4fe268f654709f450983510ab7da67812be608faf2133a90b5a
+  t.test(`contract creation data`, t => {
+    t.plan(2);
+
+    const abi = JSON.parse(fs.readFileSync(`${__dirname}/abi.json`));
+    const decoder = new InputDataDecoder(abi);
+
+    const data = fs.readFileSync(`${__dirname}/contract_creation_data.txt`)
+    const result = decoder.decodeData(data)
+
+    t.equal(result.inputs[0].toString(16), `0xB2Cb826C945D8Df01802b5cf3c4105685D4933A0`)
+    t.equal(result.inputs[1].toString(16), `STIFTUNG Dfinity FDC`)
+  })
+})

New alerts

Uses eval

Supply chain risk

Package uses eval() which is a dangerous function. This prevents the code from running in certain environments and increases the risk that the code may contain exploits or malicious behavior.

Found 1 instance in 1 package

Environment variable access

Supply chain risk

Package accesses environment variables, which may be a sign of credential stuffing or data theft.

Found 1 instance in 1 package

Long strings

Supply chain risk

Contains long string literals, which may be a sign of obfuscated or packed code.

Found 1 instance in 1 package

Fixed alerts

Major refactor

Supply chain risk

Package has recently undergone a major refactor. It may be unstable or indicate significant internal changes. Use caution when updating to versions that include significant changes.

Found 1 instance in 1 package

Dynamic require

Supply chain risk

Dynamic require can indicate the package is performing dangerous or unsafe dynamic code execution.

Found 1 instance in 1 package

Environment variable access

Supply chain risk

Package accesses environment variables, which may be a sign of credential stuffing or data theft.

Found 1 instance in 1 package

Improved metrics

Total package byte prevSize

963790

increased by56.44%

Lines of code

25676

increased by40.38%

Number of lines in readme file

97

increased by16.87%

Number of low supply chain risk alerts

8

decreased by-11.11%

Worsened metrics

Dependency count

2

increased by100%

Number of package files

14

decreased by-6.67%

Dependency changes

• + Addedethers@^2.1.3

• + Addedaes-js@3.0.0(transitive)

• + Addedelliptic@6.3.3(transitive)

• + Addedethers@2.2.6(transitive)

• + Addedethers-contracts@2.2.1(transitive)

• + Addedethers-providers@2.1.19(transitive)

• + Addedethers-utils@2.1.11(transitive)

• + Addedethers-wallet@2.1.8(transitive)

• + Addedinherits@2.0.1(transitive)

• + Addedjs-sha3@0.5.7(transitive)

• + Addedscrypt-js@2.0.3(transitive)

• + Addedsetimmediate@1.0.4(transitive)

• + Addeduuid@2.0.1(transitive)

• + Addedxmlhttprequest@1.8.0(transitive)