[Neo Core Exception] Create WalletException and use it to replace all exceptions in wallet

src/Neo/Wallets/AssetDescriptor.cs

@@ -50,22 +50,29 @@ public class AssetDescriptor
         /// <param name="asset_id">The id of the asset.</param>
         public AssetDescriptor(DataCache snapshot, ProtocolSettings settings, UInt160 asset_id)
         {
-            var contract = NativeContract.ContractManagement.GetContract(snapshot, asset_id);
-            if (contract is null) throw new ArgumentException(null, nameof(asset_id));
+            try
+            {
+                var contract = NativeContract.ContractManagement.GetContract(snapshot, asset_id);
+                if (contract is null) throw new WalletException(WalletErrorType.ContractNotFound, nameof(asset_id));
 
-            byte[] script;
-            using (ScriptBuilder sb = new())
+                byte[] script;
+                using (ScriptBuilder sb = new())
+                {
+                    sb.EmitDynamicCall(asset_id, "decimals", CallFlags.ReadOnly);
+                    sb.EmitDynamicCall(asset_id, "symbol", CallFlags.ReadOnly);
+                    script = sb.ToArray();
+                }
+                using ApplicationEngine engine = ApplicationEngine.Run(script, snapshot, settings: settings, gas: 0_30000000L);
+                if (engine.State != VMState.HALT) throw new WalletException(WalletErrorType.ExecutionFault, nameof(asset_id));
+                AssetId = asset_id;
+                AssetName = contract.Manifest.Name;
+                Symbol = engine.ResultStack.Pop().GetString();
+                Decimals = (byte)engine.ResultStack.Pop().GetInteger();
+            }
+            catch (Exception ex) when (ex is not WalletException)
             {
-                sb.EmitDynamicCall(asset_id, "decimals", CallFlags.ReadOnly);
-                sb.EmitDynamicCall(asset_id, "symbol", CallFlags.ReadOnly);
-                script = sb.ToArray();
+                throw WalletException.FromException(ex);
             }
-            using ApplicationEngine engine = ApplicationEngine.Run(script, snapshot, settings: settings, gas: 0_30000000L);
-            if (engine.State != VMState.HALT) throw new ArgumentException(null, nameof(asset_id));
-            AssetId = asset_id;
-            AssetName = contract.Manifest.Name;
-            Symbol = engine.ResultStack.Pop().GetString();
-            Decimals = (byte)engine.ResultStack.Pop().GetInteger();
         }
 
         public override string ToString()

src/Neo/Wallets/Helper.cs

@@ -9,6 +9,7 @@
 // Redistribution and use in source and binary forms with or without
 // modifications are permitted.
 
+using Akka.Routing;
 using Neo.Cryptography;
 using Neo.IO;
 using Neo.Network.P2P;
@@ -36,7 +37,14 @@ public static class Helper
         /// <returns>The signature for the <see cref="IVerifiable"/>.</returns>
         public static byte[] Sign(this IVerifiable verifiable, KeyPair key, uint network)
         {
-            return Crypto.Sign(verifiable.GetSignData(network), key.PrivateKey);
+            try
+            {
+                return Crypto.Sign(verifiable.GetSignData(network), key.PrivateKey);
+            }
+            catch (Exception ex)
+            {
+                throw WalletException.FromException(ex);
+            }
         }
 
         /// <summary>
@@ -61,17 +69,24 @@ public static string ToAddress(this UInt160 scriptHash, byte version)
         /// <returns>The converted script hash.</returns>
         public static UInt160 ToScriptHash(this string address, byte version)
         {
-            byte[] data = address.Base58CheckDecode();
-            if (data.Length != 21)
-                throw new FormatException();
-            if (data[0] != version)
-                throw new FormatException();
-            return new UInt160(data.AsSpan(1));
+            try
+            {
+                byte[] data = address.Base58CheckDecode();
+                if (data.Length != 21)
+                    throw new WalletException(WalletErrorType.FormatError, "Invalid address format: incorrect length");
+                if (data[0] != version)
+                    throw new WalletException(WalletErrorType.FormatError, "Invalid address version");
+                return new UInt160(data.AsSpan(1));
+            }
+            catch (Exception e) when (e is not WalletException)
+            {
+                throw new WalletException(WalletErrorType.FormatError, "Invalid address format");
+            }
         }
 
         internal static byte[] XOR(byte[] x, byte[] y)
         {
-            if (x.Length != y.Length) throw new ArgumentException();
+            if (x.Length != y.Length) throw new WalletException(WalletErrorType.InvalidOperation, "Arrays must have the same length");
             byte[] r = new byte[x.Length];
             for (int i = 0; i < r.Length; i++)
                 r[i] = (byte)(x[i] ^ y[i]);
@@ -90,78 +105,90 @@ internal static byte[] XOR(byte[] x, byte[] y)
         /// <returns>The network fee of the transaction.</returns>
         public static long CalculateNetworkFee(this Transaction tx, DataCache snapshot, ProtocolSettings settings, Func<UInt160, byte[]> accountScript, long maxExecutionCost = ApplicationEngine.TestModeGas)
         {
-            UInt160[] hashes = tx.GetScriptHashesForVerifying(snapshot);
-
-            // base size for transaction: includes const_header + signers + attributes + script + hashes
-            int size = Transaction.HeaderSize + tx.Signers.GetVarSize() + tx.Attributes.GetVarSize() + tx.Script.GetVarSize() + IO.Helper.GetVarSize(hashes.Length), index = -1;
-            uint exec_fee_factor = NativeContract.Policy.GetExecFeeFactor(snapshot);
-            long networkFee = 0;
-            foreach (UInt160 hash in hashes)
+            try
             {
-                index++;
-                byte[] witnessScript = accountScript(hash);
-                byte[] invocationScript = null;
+                UInt160[] hashes = tx.GetScriptHashesForVerifying(snapshot);
 
-                if (tx.Witnesses != null && witnessScript is null)
+                // base size for transaction: includes const_header + signers + attributes + script + hashes
+                int size = Transaction.HeaderSize + tx.Signers.GetVarSize() + tx.Attributes.GetVarSize() + tx.Script.GetVarSize() + IO.Helper.GetVarSize(hashes.Length), index = -1;
+                uint exec_fee_factor = NativeContract.Policy.GetExecFeeFactor(snapshot);
+                long networkFee = 0;
+                foreach (UInt160 hash in hashes)
                 {
-                    // Try to find the script in the witnesses
-                    Witness witness = tx.Witnesses[index];
-                    witnessScript = witness?.VerificationScript.ToArray();
+                    index++;
+                    byte[] witnessScript = accountScript(hash);
+                    byte[] invocationScript = null;
 
-                    if (witnessScript is null || witnessScript.Length == 0)
+                    if (tx.Witnesses != null && witnessScript is null)
                     {
-                        // Then it's a contract-based witness, so try to get the corresponding invocation script for it
-                        invocationScript = witness?.InvocationScript.ToArray();
-                    }
-                }
+                        // Try to find the script in the witnesses
+                        Witness witness = tx.Witnesses[index];
+                        witnessScript = witness?.VerificationScript.ToArray();
 
-                if (witnessScript is null || witnessScript.Length == 0)
-                {
-                    var contract = NativeContract.ContractManagement.GetContract(snapshot, hash);
-                    if (contract is null)
-                        throw new ArgumentException($"The smart contract or address {hash} is not found");
-                    var md = contract.Manifest.Abi.GetMethod(ContractBasicMethod.Verify, ContractBasicMethod.VerifyPCount);
-                    if (md is null)
-                        throw new ArgumentException($"The smart contract {contract.Hash} haven't got verify method");
-                    if (md.ReturnType != ContractParameterType.Boolean)
-                        throw new ArgumentException("The verify method doesn't return boolean value.");
-                    if (md.Parameters.Length > 0 && invocationScript is null)
-                        throw new ArgumentException("The verify method requires parameters that need to be passed via the witness' invocation script.");
+                        if (witnessScript is null || witnessScript.Length == 0)
+                        {
+                            // Then it's a contract-based witness, so try to get the corresponding invocation script for it
+                            invocationScript = witness?.InvocationScript.ToArray();
+                        }
+                    }
+                    if (witnessScript is null || witnessScript.Length == 0)
+                    {
+                        var contract = NativeContract.ContractManagement.GetContract(snapshot, hash);
+                        if (contract is null)
+                            throw new WalletException(WalletErrorType.ContractNotFound, $"The smart contract or address {hash} is not found");
+                        var md = contract.Manifest.Abi.GetMethod(ContractBasicMethod.Verify, ContractBasicMethod.VerifyPCount);
+                        if (md is null)
+                            throw new WalletException(WalletErrorType.ContractError, $"The smart contract {contract.Hash} hasn't got a verify method");
+                        if (md.ReturnType != ContractParameterType.Boolean)
+                            throw new WalletException(WalletErrorType.ContractError, "The verify method doesn't return boolean value");
+                        if (md.Parameters.Length > 0 && invocationScript is null)
+                            throw new WalletException(WalletErrorType.ContractError, "The verify method requires parameters that need to be passed via the witness' invocation script");
 
-                    // Empty verification and non-empty invocation scripts
-                    var invSize = invocationScript?.GetVarSize() ?? Array.Empty<byte>().GetVarSize();
-                    size += Array.Empty<byte>().GetVarSize() + invSize;
+                        // Empty verification and non-empty invocation scripts
+                        var invSize = invocationScript?.GetVarSize() ?? Array.Empty<byte>().GetVarSize();
+                        size += Array.Empty<byte>().GetVarSize() + invSize;
 
-                    // Check verify cost
-                    using ApplicationEngine engine = ApplicationEngine.Create(TriggerType.Verification, tx, snapshot.CloneCache(), settings: settings, gas: maxExecutionCost);
-                    engine.LoadContract(contract, md, CallFlags.ReadOnly);
-                    if (invocationScript != null) engine.LoadScript(invocationScript, configureState: p => p.CallFlags = CallFlags.None);
-                    if (engine.Execute() == VMState.FAULT) throw new ArgumentException($"Smart contract {contract.Hash} verification fault.");
-                    if (!engine.ResultStack.Pop().GetBoolean()) throw new ArgumentException($"Smart contract {contract.Hash} returns false.");
+                        // Check verify cost
+                        using ApplicationEngine engine = ApplicationEngine.Create(TriggerType.Verification, tx, snapshot.CloneCache(), settings: settings, gas: maxExecutionCost);
+                        engine.LoadContract(contract, md, CallFlags.ReadOnly);
+                        if (invocationScript != null) engine.LoadScript(invocationScript, configureState: p => p.CallFlags = CallFlags.None);
+                        if (engine.Execute() == VMState.FAULT) throw new WalletException(WalletErrorType.ExecutionFault, $"Smart contract {contract.Hash} verification fault");
+                        if (!engine.ResultStack.Pop().GetBoolean()) throw new WalletException(WalletErrorType.VerificationFailed, $"Smart contract {contract.Hash} returns false");
 
-                    maxExecutionCost -= engine.FeeConsumed;
-                    if (maxExecutionCost <= 0) throw new InvalidOperationException("Insufficient GAS.");
-                    networkFee += engine.FeeConsumed;
-                }
-                else if (IsSignatureContract(witnessScript))
-                {
-                    size += 67 + witnessScript.GetVarSize();
-                    networkFee += exec_fee_factor * SignatureContractCost();
+                        maxExecutionCost -= engine.FeeConsumed;
+                        if (maxExecutionCost <= 0) throw new WalletException(WalletErrorType.InsufficientFunds, "Insufficient GAS");
+                        networkFee += engine.FeeConsumed;
+                    }
+                    else if (IsSignatureContract(witnessScript))
+                    {
+                        size += 67 + witnessScript.GetVarSize();
+                        networkFee += exec_fee_factor * SignatureContractCost();
+                    }
+                    else if (IsMultiSigContract(witnessScript, out int m, out int n))
+                    {
+                        int size_inv = 66 * m;
+                        size += IO.Helper.GetVarSize(size_inv) + size_inv + witnessScript.GetVarSize();
+                        networkFee += exec_fee_factor * MultiSignatureContractCost(m, n);
+                    }
+                    // We can support more contract types in the future.
                 }
-                else if (IsMultiSigContract(witnessScript, out int m, out int n))
+                networkFee += size * NativeContract.Policy.GetFeePerByte(snapshot);
+                foreach (TransactionAttribute attr in tx.Attributes)
                 {
-                    int size_inv = 66 * m;
-                    size += IO.Helper.GetVarSize(size_inv) + size_inv + witnessScript.GetVarSize();
-                    networkFee += exec_fee_factor * MultiSignatureContractCost(m, n);
+                    networkFee += attr.CalculateNetworkFee(snapshot, tx);
                 }
-                // We can support more contract types in the future.
+                return networkFee;
             }
-            networkFee += size * NativeContract.Policy.GetFeePerByte(snapshot);
-            foreach (TransactionAttribute attr in tx.Attributes)
+            catch (Exception ex) when (ex is not WalletException)
             {
-                networkFee += attr.CalculateNetworkFee(snapshot, tx);
+                throw new WalletException(WalletErrorType.UnknownError, ex.Message, ex);
             }
-            return networkFee;
+        }
+
+        internal static void ThrowIfNull(object argument, string paramName)
+        {
+            if (argument == null)
+                throw new WalletException(WalletErrorType.ArgumentNull, $"Argument {paramName} cannot be null.");
         }
     }
 }

src/Neo/Wallets/KeyPair.cs

@@ -47,15 +47,23 @@ public class KeyPair : IEquatable<KeyPair>
         public KeyPair(byte[] privateKey)
         {
             if (privateKey.Length != 32 && privateKey.Length != 96 && privateKey.Length != 104)
-                throw new ArgumentException(null, nameof(privateKey));
+                throw new WalletException(WalletErrorType.InvalidPrivateKey, nameof(privateKey));
             PrivateKey = privateKey[^32..];
             if (privateKey.Length == 32)
             {
                 PublicKey = Cryptography.ECC.ECCurve.Secp256r1.G * privateKey;
             }
             else
             {
-                PublicKey = Cryptography.ECC.ECPoint.FromBytes(privateKey, Cryptography.ECC.ECCurve.Secp256r1);
+                try
+                {
+                    PublicKey = Cryptography.ECC.ECPoint.FromBytes(privateKey, Cryptography.ECC.ECCurve.Secp256r1);
+                }
+                catch
+                {
+                    throw new WalletException(WalletErrorType.InvalidPrivateKey, nameof(privateKey));
+                }
+
             }
         }
 
@@ -119,30 +127,44 @@ public string Export(string passphrase, byte version, int N = 16384, int r = 8,
         /// <returns>The private key in NEP-2 format.</returns>
         public string Export(byte[] passphrase, byte version, int N = 16384, int r = 8, int p = 8)
         {
-            UInt160 script_hash = Contract.CreateSignatureRedeemScript(PublicKey).ToScriptHash();
-            string address = script_hash.ToAddress(version);
-            byte[] addresshash = Encoding.ASCII.GetBytes(address).Sha256().Sha256()[..4];
-            byte[] derivedkey = SCrypt.Generate(passphrase, addresshash, N, r, p, 64);
-            byte[] derivedhalf1 = derivedkey[..32];
-            byte[] derivedhalf2 = derivedkey[32..];
-            byte[] encryptedkey = Encrypt(XOR(PrivateKey, derivedhalf1), derivedhalf2);
-            Span<byte> buffer = stackalloc byte[39];
-            buffer[0] = 0x01;
-            buffer[1] = 0x42;
-            buffer[2] = 0xe0;
-            addresshash.CopyTo(buffer[3..]);
-            encryptedkey.CopyTo(buffer[7..]);
-            return Base58.Base58CheckEncode(buffer);
+            try
+            {
+                UInt160 script_hash = Contract.CreateSignatureRedeemScript(PublicKey).ToScriptHash();
+                string address = script_hash.ToAddress(version);
+                byte[] addresshash = Encoding.ASCII.GetBytes(address).Sha256().Sha256()[..4];
+                byte[] derivedkey = SCrypt.Generate(passphrase, addresshash, N, r, p, 64);
+                byte[] derivedhalf1 = derivedkey[..32];
+                byte[] derivedhalf2 = derivedkey[32..];
+                byte[] encryptedkey = Encrypt(XOR(PrivateKey, derivedhalf1), derivedhalf2);
+                Span<byte> buffer = stackalloc byte[39];
+                buffer[0] = 0x01;
+                buffer[1] = 0x42;
+                buffer[2] = 0xe0;
+                addresshash.CopyTo(buffer[3..]);
+                encryptedkey.CopyTo(buffer[7..]);
+                return Base58.Base58CheckEncode(buffer);
+            }
+            catch (Exception e)
+            {
+                throw WalletException.FromException(e);
+            }
         }
 
         private static byte[] Encrypt(byte[] data, byte[] key)
         {
-            using Aes aes = Aes.Create();
-            aes.Key = key;
-            aes.Mode = CipherMode.ECB;
-            aes.Padding = PaddingMode.None;
-            using ICryptoTransform encryptor = aes.CreateEncryptor();
-            return encryptor.TransformFinalBlock(data, 0, data.Length);
+            try
+            {
+                using Aes aes = Aes.Create();
+                aes.Key = key;
+                aes.Mode = CipherMode.ECB;
+                aes.Padding = PaddingMode.None;
+                using ICryptoTransform encryptor = aes.CreateEncryptor();
+                return encryptor.TransformFinalBlock(data, 0, data.Length);
+            }
+            catch (Exception e)
+            {
+                throw WalletException.FromException(e);
+            }
         }
 
         public override int GetHashCode()