Merge pull request #905 from ethereum/fixStructinMapping

Fix Decoding struct in mapping

remix-debug/src/solidity-decoder/types/Mapping.js

@@ -12,10 +12,11 @@ class Mapping extends RefType {
   }
 
   async decodeFromStorage (location, storageResolver) {
+    var corrections = this.valueType.members ? this.valueType.members.map((value) => { return value.storagelocation }) : []
     if (!this.initialDecodedState) { // cache the decoded initial storage
       var mappingsInitialPreimages
       try {
-        mappingsInitialPreimages = await storageResolver.initialMappingsLocation()
+        mappingsInitialPreimages = await storageResolver.initialMappingsLocation(corrections)
         this.initialDecodedState = await this.decodeMappingsLocation(mappingsInitialPreimages, location, storageResolver)
       } catch (e) {
         return {
@@ -24,7 +25,7 @@ class Mapping extends RefType {
         }
       }
     }
-    var mappingPreimages = await storageResolver.mappingsLocation()
+    var mappingPreimages = await storageResolver.mappingsLocation(corrections)
     var ret = await this.decodeMappingsLocation(mappingPreimages, location, storageResolver) // fetch mapping storage changes
     ret = Object.assign({}, this.initialDecodedState, ret) // merge changes
     return {

remix-debug/src/solidity-decoder/types/util.js

@@ -9,6 +9,7 @@ module.exports = {
   extractHexByteSlice: extractHexByteSlice,
   toBN: toBN,
   add: add,
+  sub: sub,
   extractLocation: extractLocation,
   removeLocation: removeLocation,
   normalizeHex: normalizeHex,
@@ -88,6 +89,10 @@ function add (value1, value2) {
   return toBN(value1).add(toBN(value2))
 }
 
+function sub (value1, value2) {
+  return toBN(value1).sub(toBN(value2))
+}
+
 function removeLocation (type) {
   return type.replace(/( storage ref| storage pointer| memory| calldata)/g, '')
 }

remix-debug/src/storage/mappingPreimages.js

@@ -1,3 +1,4 @@
+var util = require('../solidity-decoder/types/util')
 
 module.exports = {
   decodeMappingsKeys: decodeMappingsKeys
@@ -8,15 +9,22 @@ module.exports = {
   * like { "<mapping_slot>" : { "<mapping-key1>": preimageOf1 }, { "<mapping-key2>": preimageOf2 }, ... }
   *
   * @param {Object} storage  - storage given by storage Viewer (basically a mapping hashedkey : {key, value})
+  * @param {Array} corrections - used in case the calculated sha3 has been modifyed before SSTORE (notably used for struct in mapping).
   * @param {Function} callback  - calback
   * @return {Map} - solidity mapping location (e.g { "<mapping_slot>" : { "<mapping-key1>": preimageOf1 }, { "<mapping-key2>": preimageOf2 }, ... })
   */
-async function decodeMappingsKeys (web3, storage, callback) {
+async function decodeMappingsKeys (web3, storage, corrections, callback) {
   var ret = {}
+  if (!corrections.length) corrections.push({offset: 0, slot: 0})
   for (var hashedLoc in storage) {
     var preimage
     try {
-      preimage = await getPreimage(web3, storage[hashedLoc].key)
+      var key = storage[hashedLoc].key
+      for (var k in corrections) {
+        var corrected = util.sub(key, corrections[k].slot).toString(16)
+        preimage = await getPreimage(web3, '0x' + corrected)
+        if (preimage) break
+      }
     } catch (e) {
     }
     if (preimage) {

remix-debug/src/storage/storageResolver.js

@@ -33,11 +33,13 @@ class StorageResolver {
    * compute the mappgings type locations for the current address (cached for a debugging session)
    * note: that only retrieve the first 100 items.
    *
-   * @param {String} address  - contract address
+   * @param {Object} tx
+   * @param {Int} stepIndex
    * @param {Object} address  - storage
+   * @param {Array} corrections - used in case the calculated sha3 has been modifyed before SSTORE (notably used for struct in mapping).
    * @return {Function} - callback
    */
-  initialPreimagesMappings (tx, stepIndex, address, callback) {
+  initialPreimagesMappings (tx, stepIndex, address, corrections, callback) {
     const self = this
     if (this.preimagesMappingByAddress[address]) {
       return callback(null, this.preimagesMappingByAddress[address])
@@ -46,7 +48,7 @@ class StorageResolver {
       if (error) {
         return callback(error)
       }
-      mappingPreimages.decodeMappingsKeys(self.web3, storage, (error, mappings) => {
+      mappingPreimages.decodeMappingsKeys(self.web3, storage, corrections, (error, mappings) => {
         if (error) {
           callback(error)
         } else {

remix-debug/src/storage/storageViewer.js

@@ -72,12 +72,12 @@ class StorageViewer {
   /**
     * return all the possible mappings locations for the current context (cached) do not return state changes during the current transaction
     *
-    * @param {Function} callback
+    * @param {Array} corrections - used in case the calculated sha3 has been modifyed before SSTORE (notably used for struct in mapping).
     */
-  async initialMappingsLocation () {
+  async initialMappingsLocation (corrections) {
     if (!this.initialMappingsLocationPromise) {
       this.initialMappingsLocationPromise = new Promise((resolve, reject) => {
-        this.storageResolver.initialPreimagesMappings(this.context.tx, this.context.stepIndex, this.context.address, (error, initialMappingsLocation) => {
+        this.storageResolver.initialPreimagesMappings(this.context.tx, this.context.stepIndex, this.context.address, corrections, (error, initialMappingsLocation) => {
           if (error) {
             reject(error)
           } else {
@@ -92,12 +92,12 @@ class StorageViewer {
   /**
     * return all the possible mappings locations for the current context (cached) and current mapping slot. returns state changes during the current transaction
     *
-    * @param {Function} callback
+    * @param {Array} corrections - used in case the calculated sha3 has been modifyed before SSTORE (notably used for struct in mapping).
     */
-  async mappingsLocation () {
+  async mappingsLocation (corrections) {
     if (!this.currentMappingsLocationPromise) {
       this.currentMappingsLocationPromise = new Promise((resolve, reject) => {
-        this.extractMappingsLocationChanges(this.storageChanges, (error, mappingsLocationChanges) => {
+        this.extractMappingsLocationChanges(this.storageChanges, corrections, (error, mappingsLocationChanges) => {
           if (error) {
             reject(error)
           } else {
@@ -111,14 +111,14 @@ class StorageViewer {
 
   /**
     * retrieve mapping location changes from the storage changes.
-    *
-    * @param {Function} callback
+    * @param {Map} storageChanges
+    * @param {Array} corrections - used in case the calculated sha3 has been modifyed before SSTORE (notably used for struct in mapping).
     */
-  extractMappingsLocationChanges (storageChanges, callback) {
+  extractMappingsLocationChanges (storageChanges, corrections, callback) {
     if (this.mappingsLocationChanges) {
       return callback(null, this.mappingsLocationChanges)
     }
-    mappingPreimages.decodeMappingsKeys(this.web3, storageChanges, (error, mappings) => {
+    mappingPreimages.decodeMappingsKeys(this.web3, storageChanges, corrections, (error, mappings) => {
       if (!error) {
         this.mappingsLocationChanges = mappings
         return callback(null, this.mappingsLocationChanges)