Merge pull request #273 from EYBlockchain/lydia/restoreDB

Restore Lost database

README.md

@@ -329,6 +329,9 @@ You can also filter these commitments by variable name. Using the example above,
 ```
 as a GET request to `http://localhost:3000/getCommitmentsByVariableName`.
 
+If the commitment database that stores commitment preimages is lost you can restore the DB (by decrypting the onchain encryptions of the preimages) by sending a POST request to `http://localhost:3000/backupDataRetriever`.
+
+
 #### Using secret states in the constructor
 
 Starlight handles secret initiation in the constructor by creating a proof at the setup stage. Any user supplied inputs will be prompted for in the command line when running `./bin/setup`.

src/boilerplate/common/generic-test.mjs

@@ -36,7 +36,7 @@ describe('FUNCTION_NAME', async function () {
         await startEventFilter('CONTRACT_NAME');
         // this calls your function! It returns the tx from the shield contract
         // you can replace the values below - numbers are randomly generated
-        const { tx , encEvent } = await FUNCTION_NAME(FUNCTION_SIG_1);
+        const { tx , encEvent, encBackupEvent } = await FUNCTION_NAME(FUNCTION_SIG_1);
         // prints the tx
         console.log(tx);
         // reassigns leafIndex to the index of the first commitment added by this function

src/boilerplate/common/number-theory.mjs

@@ -285,6 +285,34 @@ function compressStarlightKey(publicKeyPoint) {
   return publicKey;
 }
 
+/**
+Encrypt messages encrypted with KEM-DEM
+@param {string[]} Plaintext - hex string[]
+@param {string} SendersecretKey - hex string
+@param {string[2]} RecieverPublicKey - hex string[]
+@return {string[]} plainText - int string[]
+*/
+function encrypt(plaintext, secretKey, recieverPublicKey) {
+  const encryptedMessages = [];
+  const sharedSecret = scalarMult(secretKey, [
+    BigInt(recieverPublicKey[0]),
+    BigInt(recieverPublicKey[1]),
+  ]);
+  const key = poseidonHash([
+    sharedSecret[0],
+    sharedSecret[1],
+    BigInt(DOMAIN_KEM),
+  ]);
+  plaintext.forEach((msg, index) => {
+    const hash = poseidonHash([key.bigInt, BigInt(DOMAIN_DEM), BigInt(index)]);
+    encryptedMessages[index] = addMod([BigInt(msg), hash.bigInt], Fp);
+    while (encryptedMessages[index] < 0n) {
+      encryptedMessages[index] += Fp;
+    }
+  });
+  return encryptedMessages;
+}
+
 /**
 Decrypt messages encrypted with KEM-DEM
 @param {string[]} encryptedMessages - hex string[]
@@ -368,7 +396,8 @@ function sbox(state, f, p, r) {
   const N = state.length;
   state[0] = powerMod(state[0], 5n, q);
   for (let i = 1; i < N; i++) {
-    state[i] = r < f / 2 || r >= f / 2 + p ? powerMod(state[i], 5n, q) : state[i];
+    state[i] =
+      r < f / 2 || r >= f / 2 + p ? powerMod(state[i], 5n, q) : state[i];
   }
   return state;
 }
@@ -391,7 +420,24 @@ function poseidonHash(_inputs) {
   const inputs = _inputs;
   const N = inputs.length;
   const t = N + 1;
-  const roundsP = [56, 57, 56, 60, 60, 63, 64, 63, 60, 66, 60, 65, 70, 60, 64, 68];
+  const roundsP = [
+    56,
+    57,
+    56,
+    60,
+    60,
+    63,
+    64,
+    63,
+    60,
+    66,
+    60,
+    65,
+    70,
+    60,
+    64,
+    68,
+  ];
   const f = 8;
   const p = roundsP[t - 2];
   const c = C[t - 2];
@@ -421,6 +467,7 @@ export {
   scalarMult,
   compressStarlightKey,
   decompressStarlightKey,
+  encrypt,
   decrypt,
   poseidonHash,
   sharedSecretKey,

src/boilerplate/common/services/generic-api_services.mjs

@@ -34,10 +34,10 @@ export async function service_FUNCTION_NAME (req, res, next){
     await startEventFilter('CONTRACT_NAME');
     const FUNCTION_SIG;
     CONSTRUCTOR_INPUTS;
-    const { tx , encEvent, _RESPONSE_} = await FUNCTION_NAME(FUNCTION_SIG);
+    const { tx , encEvent, encBackupEvent, _RESPONSE_} = await FUNCTION_NAME(FUNCTION_SIG);
     // prints the tx
     console.log(tx);
-    res.send({tx, encEvent, _RESPONSE_});
+    res.send({tx, encEvent, encBackupEvent, _RESPONSE_});
     // reassigns leafIndex to the index of the first commitment added by this function
     if (tx.event) {
       leafIndex = tx.returnValues[0];

src/boilerplate/contract/solidity/nodes/ContractBoilerplateGenerator.ts

@@ -125,6 +125,7 @@ class ContractBoilerplateGenerator {
           delete parameterList[ paramtype ];
         }
         const newList: string[] = [];
+
         params?.forEach(circuitParamNode => {
           switch (circuitParamNode.bpType) {
             case 'nullification':
@@ -144,8 +145,9 @@ class ContractBoilerplateGenerator {
               if (!newList.includes(circuitParamNode.bpType)) newList.push(circuitParamNode.bpType);
               break;
             case 'encryption':
-              returnpara['returnParameters'] ??= [];
-              returnpara['returnParameters'].push(circuitParamNode.bpType);
+
+              returnpara['encryptionParameters'] ??= [];
+              returnpara['encryptionParameters'].push(circuitParamNode.bpType);
               break;
             case undefined: {
               if (
@@ -176,6 +178,7 @@ class ContractBoilerplateGenerator {
         parameterList = {...parameterList, ...returnpara};    
       }
      circuitParams[ functionName ] = parameterList;
+
     }
       const constructorContainsSecret = Object.values(this.scope.bindings).some((binding: any) => binding.node.kind === 'constructor');
       return { nullifiersRequired, oldCommitmentAccessRequired, newCommitmentsRequired, containsAccessedOnlyState, encryptionRequired, constructorContainsSecret, circuitParams, isjoinSplitCommitmentsFunction};

src/boilerplate/contract/solidity/nodes/FunctionBoilerplateGenerator.ts

@@ -117,18 +117,17 @@ class FunctionBoilerplateGenerator {
 
       path.node._newASTPointer.body.statements?.forEach((node) => {
         if(node.expression?.nodeType === 'InternalFunctionCall'){
-          if(node.expression.parameters.includes('cipherText') ) 
-           internalFunctionEncryptionRequired = true 
+          if(node.expression.encryptionRequired) 
+           internalFunctionEncryptionRequired = true; 
 
         }
 
       })
 
 
-      if(path.node.returnParameters.parameters.length === 0 && !indicators.encryptionRequired && !internalFunctionEncryptionRequired) {
+      if(path.node.returnParameters.parameters.length === 0 && !indicators.encryptionRequired && !internalFunctionEncryptionRequired){
         publicParams?.push({ name: 1, type: 'uint256', dummy: true , inCircuit: true });
       }
-
       return {
         ...(publicParams?.length && { customInputs: publicParams }),
         functionName,

src/boilerplate/contract/solidity/raw/ContractBoilerplateGenerator.ts

@@ -43,7 +43,16 @@ class ContractBoilerplateGenerator {
         ...(encryptionRequired ? [`
           event EncryptedData(uint256[] cipherText, uint256[2] ephPublicKey);`] : []),
 
-          ...nullifiersRequired ? [`
+        ...(newCommitmentsRequired ? [`
+        struct BackupDataElement {
+          string varName;
+          uint256[] cipherText;
+          uint256 ephPublicKey;
+      } \n
+          event EncryptedBackupData(BackupDataElement[] encPreimages); 
+          `] : []),
+
+        ...nullifiersRequired ? [`
           uint256 public newNullifierRoot;`] : [],
 
         ...(oldCommitmentAccessRequired ? [`
@@ -121,7 +130,6 @@ class ContractBoilerplateGenerator {
       let verifyInput: string[] = [];
 
       const verifyInputsMap = (type: string, input: string, counter: any) => {
-
         if(type  === 'parameters'){
         switch (input) {
           case 'nullifierRoot':  
@@ -150,8 +158,7 @@ class ContractBoilerplateGenerator {
             break;
         }
       }
-        else if(type  === 'returnParameters') {
-
+        else if(type  === 'returnParameters' || type  === 'encryptionParameters') {
           switch (input) {
             case 'encryption':
               verifyInput.push( `
@@ -222,13 +229,13 @@ class ContractBoilerplateGenerator {
               newCommitments: 0,
               encryption: 0,
             };
-            _inputs.map(i => verifyInputsMap(type, i, counter));
+            _inputs?.map(i => verifyInputsMap(type, i, counter));
 
 
 
           }
 
-          if(_params && !(Object.keys(_params).includes('returnParameters'))) verifyInput.push(`
+          if(_params && !(Object.keys(_params).includes('returnParameters')) &&!(Object.keys(_params).includes('encryptionParameters'))) verifyInput.push(`
             inputs[k++] = 1;`) 
 
         verifyInputs.push(`

src/boilerplate/contract/solidity/raw/FunctionBoilerplateGenerator.ts

@@ -43,12 +43,12 @@ class FunctionBoilerplateGenerator {
       if (isConstructor && encryptionRequired) throw new Error(`There shouldn't be any secret states that require sharing encrypted data in the constructor.`)
       const visibility = isConstructor ? 'memory' : 'calldata';
       return [
-        ...(newNullifiers ? [`uint256 nullifierRoot, uint256 latestNullifierRoot,uint256[] ${visibility} newNullifiers`] : []), // nullifiers and nullifier root exist together
-        ...(commitmentRoot ? [`uint256 commitmentRoot`] : []),
-        ...(newCommitments ? [`uint256[] ${visibility} newCommitments`] : []),
-        ...(encryptionRequired ? [`uint256[][] calldata cipherText`] : []),
-        ...(encryptionRequired ? [`uint256[2][] calldata ephPubKeys`] : []),
-        ...(newCommitments || newNullifiers ? [`uint256[] ${visibility} proof`] : []),
+        // ...(newNullifiers ? [`uint256 nullifierRoot, uint256 latestNullifierRoot,uint256[] ${visibility} newNullifiers`] : []), // nullifiers and nullifier root exist together
+        // ...(commitmentRoot ? [`uint256 commitmentRoot`] : []),
+        // ...(newCommitments ? [`uint256[] ${visibility} newCommitments`] : []),
+        // ...(encryptionRequired ? [`uint256[][] calldata cipherText`] : []),
+        // ...(encryptionRequired ? [`uint256[2][] calldata ephPubKeys`] : []),
+        ...(newCommitments || newNullifiers ? [`Inputs ${visibility} inputs, uint256[] ${visibility} proof, BackupDataElement[] memory BackupData`] : []),
       ];
     },
 
@@ -64,20 +64,13 @@ class FunctionBoilerplateGenerator {
       encryptionRequired
     }): string[] {
       // prettier-ignore
-
       let parameter = [
         ...(customInputs ? customInputs.filter(input => !input.dummy && input.isParam)
         .map(input => input.structName ? `(${input.properties.map(p => p.type)})` : input.isConstantArray ? `${input.type}[${input.isConstantArray}]` : input.type) : []), // TODO arrays of structs/ structs of arrays
-      ...(newNullifiers ? [`uint256`] : []),
-      ...(newNullifiers ? [`uint256`] : []),
-      ...(newNullifiers ? [`uint256[]`] : []), 
-      ...(commitmentRoot  ? [`uint256`] : []),
-      ...(newCommitments  ? [`uint256[]`] : []),
-      ...(encryptionRequired  ? [`uint256[][]`] : []),
-      ...(encryptionRequired ? [`uint256[2][]`] : []),
+      `(uint256,uint256,uint256[],uint256,uint256[],uint256[])`,
       `uint256[]`,
+      `(string,uint256[],uint256)[]`,
     ].filter(para => para !== undefined); // Added for return parameter 
-
       customInputs?.forEach((input, i) => {
         if (input.isConstantArray) {
           const expanded = [];
@@ -93,60 +86,65 @@ class FunctionBoilerplateGenerator {
         }
         if (input.structName) customInputs[i] = input.properties;
       });
-
 
       let msgSigCheck = ([...(isConstructor  ? [] : [`bytes4 sig = bytes4(keccak256("${functionName}(${parameter})")) ;  \n \t \t \t if (sig == msg.sig)`])]);
-
-      customInputs = customInputs?.flat(Infinity).filter(p => p.inCircuit);
-
+      customInputs = customInputs?.flat(Infinity).filter(p => (p.inCircuit || p.isReturn));
+
+      const addCustomInputs = !customInputs  || (customInputs?.length == 1 && customInputs[0].name == '1') ? false : true;
       return [
-        `
-          Inputs memory inputs;`,
-
-        ...(customInputs?.length ?
+        // `
+        //   Inputs memory inputs;`,
+  
+        ...(addCustomInputs ?
           [`
-          inputs.customInputs = new uint[](${customInputs.flat(Infinity).length});
+          Inputs memory updatedInputs = inputs;
+          updatedInputs.customInputs = new uint[](${customInputs.flat(Infinity).length});
         	${customInputs.flat(Infinity).map((input: any, i: number) => {
-            if (input.type === 'address') return `inputs.customInputs[${i}] = uint256(uint160(address(${input.name})));`;
-            if ((input.type === 'bool' || input.typeName?.name === 'bool' ) && !['0', '1'].includes(input.name)) return `inputs.customInputs[${i}] = ${input.name} == false ? 0 : 1;`;
-            return `inputs.customInputs[${i}] = ${input.name};`;
-          }).join('\n')}`]
-          : []),
+            if (input.type === 'address') return `updatedInputs.customInputs[${i}] = uint256(uint160(address(${input.name})));`;
+            if ((input.type === 'bool' || input.typeName?.name === 'bool' ) && !['0', '1'].includes(input.name)) return `updatedInputs.customInputs[${i}] = ${input.name} == false ? 0 : 1;`;
+            if (input.isCommitment) return ``;
+            return `updatedInputs.customInputs[${i}] = ${input.name};`;
+          }).join('\n')}
+          ${msgSigCheck.join('\n')}
+          verify(proof, uint(FunctionNames.${functionName}), updatedInputs);`]
+          : [`${msgSigCheck.join('\n')}
+          verify(proof, uint(FunctionNames.${functionName}), inputs);`]),
 
-        ...(newNullifiers ? [`
-        inputs.nullifierRoot = nullifierRoot; `] : []),
+        //   ...(newNullifiers ? [`
+        // //   inputs.nullifierRoot = nullifierRoot; `] : []),
 
-        ...(newNullifiers ? [`
-        inputs.latestNullifierRoot = latestNullifierRoot; `] : []),
+        //   ...(newNullifiers ? [`
+        //   inputs.latestNullifierRoot = latestNullifierRoot; `] : []),
 
 
-        ...(newNullifiers ? [`
-          inputs.newNullifiers = newNullifiers;
-           `] : []),
+        // ...(newNullifiers ? [`
+        //   inputs.newNullifiers = newNullifiers;
+        //    `] : []),
 
-        ...(commitmentRoot ? [`
-          inputs.commitmentRoot = commitmentRoot;`] : []),
+        // ...(commitmentRoot ? [`
+        //   inputs.commitmentRoot = commitmentRoot;`] : []),
 
-        ...(newCommitments ? [`
-          inputs.newCommitments = newCommitments;`] : []),
+        // ...(newCommitments ? [`
+        //   inputs.newCommitments = newCommitments;`] : []),
 
-        ...(encryptionRequired ? [`
-          inputs.cipherText = cipherText;`] : []),
-
-        ...(encryptionRequired ? [`
-          inputs.encKeys = ephPubKeys;`] : []),
-        `
-          ${msgSigCheck.join('\n')}`,
-        `
-          verify(proof, uint(FunctionNames.${functionName}), inputs);`,
+        // ...(encryptionRequired ? [`
+        //   inputs.cipherText = cipherText;`] : []),
 
+        // ...(encryptionRequired ? [`
+        //   inputs.encKeys = ephPubKeys;`] : []),
+
         ...(encryptionRequired ? [`
-          for (uint j; j < cipherText.length; j++) {
+          for (uint j; j < inputs.cipherText.length; j++) {
             // this seems silly (it is) but its the only way to get the event to emit properly
-            uint256[2] memory ephKeyToEmit = ephPubKeys[j];
-            uint256[] memory cipherToEmit = cipherText[j];
+            uint256[2] memory ephKeyToEmit = inputs.encKeys[j];
+            uint256[] memory cipherToEmit = inputs.cipherText[j];
             emit EncryptedData(cipherToEmit, ephKeyToEmit);
-          }`] : []),
+          }`]
+          : []),
+        ...(newCommitments ? [`
+            // this seems silly (it is) but its the only way to get the event to emit properly
+            emit EncryptedBackupData(BackupData);`]
+          : []),
       ];
     },
   };