From 08e782c61ff5eb1f5890238c970c95bc6d19c3a6 Mon Sep 17 00:00:00 2001 From: Marius van der Wijden Date: Thu, 14 Oct 2021 13:33:28 +0200 Subject: [PATCH] accounts/abi: add basic support for error types (#23161) This is the initial step for support of Solidity errors in contract bindings. As of this change, errors can be decoded, but are not supported in bindings yet. Closes #23157 --- accounts/abi/abi.go | 55 ++++++++---------- accounts/abi/abi_test.go | 14 +++++ accounts/abi/bind/bind_test.go | 55 ++++++++++++++++++ accounts/abi/error.go | 103 ++++++++++++++++++--------------- accounts/abi/error_handling.go | 82 ++++++++++++++++++++++++++ 5 files changed, 230 insertions(+), 79 deletions(-) create mode 100644 accounts/abi/error_handling.go diff --git a/accounts/abi/abi.go b/accounts/abi/abi.go index 5ca7c241db..cd2f4d7978 100644 --- a/accounts/abi/abi.go +++ b/accounts/abi/abi.go @@ -34,6 +34,7 @@ type ABI struct { Constructor Method Methods map[string]Method Events map[string]Event + Errors map[string]Error // Additional "special" functions introduced in solidity v0.6.0. // It's separated from the original default fallback. Each contract @@ -157,12 +158,13 @@ func (abi *ABI) UnmarshalJSON(data []byte) error { } abi.Methods = make(map[string]Method) abi.Events = make(map[string]Event) + abi.Errors = make(map[string]Error) for _, field := range fields { switch field.Type { case "constructor": abi.Constructor = NewMethod("", "", Constructor, field.StateMutability, field.Constant, field.Payable, field.Inputs, nil) case "function": - name := abi.overloadedMethodName(field.Name) + name := overloadedName(field.Name, func(s string) bool { _, ok := abi.Methods[s]; return ok }) abi.Methods[name] = NewMethod(name, field.Name, Function, field.StateMutability, field.Constant, field.Payable, field.Inputs, field.Outputs) case "fallback": // New introduced function type in v0.6.0, check more detail @@ -182,8 +184,10 @@ func (abi *ABI) UnmarshalJSON(data []byte) error { } abi.Receive = NewMethod("", "", Receive, field.StateMutability, field.Constant, field.Payable, nil, nil) case "event": - name := abi.overloadedEventName(field.Name) + name := overloadedName(field.Name, func(s string) bool { _, ok := abi.Events[s]; return ok }) abi.Events[name] = NewEvent(name, field.Name, field.Anonymous, field.Inputs) + case "error": + abi.Errors[field.Name] = NewError(field.Name, field.Inputs) default: return fmt.Errorf("abi: could not recognize type %v of field %v", field.Type, field.Name) } @@ -191,36 +195,6 @@ func (abi *ABI) UnmarshalJSON(data []byte) error { return nil } -// overloadedMethodName returns the next available name for a given function. -// Needed since solidity allows for function overload. -// -// e.g. if the abi contains Methods send, send1 -// overloadedMethodName would return send2 for input send. -func (abi *ABI) overloadedMethodName(rawName string) string { - name := rawName - _, ok := abi.Methods[name] - for idx := 0; ok; idx++ { - name = fmt.Sprintf("%s%d", rawName, idx) - _, ok = abi.Methods[name] - } - return name -} - -// overloadedEventName returns the next available name for a given event. -// Needed since solidity allows for event overload. -// -// e.g. if the abi contains events received, received1 -// overloadedEventName would return received2 for input received. -func (abi *ABI) overloadedEventName(rawName string) string { - name := rawName - _, ok := abi.Events[name] - for idx := 0; ok; idx++ { - name = fmt.Sprintf("%s%d", rawName, idx) - _, ok = abi.Events[name] - } - return name -} - // MethodById looks up a method by the 4-byte id, // returns nil if none found. func (abi *ABI) MethodById(sigdata []byte) (*Method, error) { @@ -277,3 +251,20 @@ func UnpackRevert(data []byte) (string, error) { } return unpacked[0].(string), nil } + +// overloadedName returns the next available name for a given thing. +// Needed since solidity allows for overloading. +// +// e.g. if the abi contains Methods send, send1 +// overloadedName would return send2 for input send. +// +// overloadedName works for methods, events and errors. +func overloadedName(rawName string, isAvail func(string) bool) string { + name := rawName + ok := isAvail(name) + for idx := 0; ok; idx++ { + name = fmt.Sprintf("%s%d", rawName, idx) + ok = isAvail(name) + } + return name +} diff --git a/accounts/abi/abi_test.go b/accounts/abi/abi_test.go index a022ec5f9d..cc8dfc61c3 100644 --- a/accounts/abi/abi_test.go +++ b/accounts/abi/abi_test.go @@ -295,6 +295,20 @@ func TestOverloadedMethodSignature(t *testing.T) { check("bar0", "bar(uint256,uint256)", false) } +func TestCustomErrors(t *testing.T) { + json := `[{ "inputs": [ { "internalType": "uint256", "name": "", "type": "uint256" } ],"name": "MyError", "type": "error"} ]` + abi, err := JSON(strings.NewReader(json)) + if err != nil { + t.Fatal(err) + } + check := func(name string, expect string) { + if abi.Errors[name].Sig != expect { + t.Fatalf("The signature of overloaded method mismatch, want %s, have %s", expect, abi.Methods[name].Sig) + } + } + check("MyError", "MyError(uint256)") +} + func TestMultiPack(t *testing.T) { abi, err := JSON(strings.NewReader(jsondata)) if err != nil { diff --git a/accounts/abi/bind/bind_test.go b/accounts/abi/bind/bind_test.go index 6d9052f88b..5a436607ce 100644 --- a/accounts/abi/bind/bind_test.go +++ b/accounts/abi/bind/bind_test.go @@ -1850,6 +1850,61 @@ var bindTests = []struct { if count != 1 { t.Fatal("Unexpected contract event number") } + `, + nil, + nil, + nil, + nil, + }, + // Test errors introduced in v0.8.4 + { + `NewErrors`, + ` + pragma solidity >0.8.4; + + contract NewErrors { + error MyError(uint256); + error MyError1(uint256); + error MyError2(uint256, uint256); + error MyError3(uint256 a, uint256 b, uint256 c); + function Error() public pure { + revert MyError3(1,2,3); + } + } + `, + []string{"0x6080604052348015600f57600080fd5b5060998061001e6000396000f3fe6080604052348015600f57600080fd5b506004361060285760003560e01c8063726c638214602d575b600080fd5b60336035565b005b60405163024876cd60e61b815260016004820152600260248201526003604482015260640160405180910390fdfea264697066735822122093f786a1bc60216540cd999fbb4a6109e0fef20abcff6e9107fb2817ca968f3c64736f6c63430008070033"}, + []string{`[{"inputs":[{"internalType":"uint256","name":"","type":"uint256"}],"name":"MyError","type":"error"},{"inputs":[{"internalType":"uint256","name":"","type":"uint256"}],"name":"MyError1","type":"error"},{"inputs":[{"internalType":"uint256","name":"","type":"uint256"},{"internalType":"uint256","name":"","type":"uint256"}],"name":"MyError2","type":"error"},{"inputs":[{"internalType":"uint256","name":"a","type":"uint256"},{"internalType":"uint256","name":"b","type":"uint256"},{"internalType":"uint256","name":"c","type":"uint256"}],"name":"MyError3","type":"error"},{"inputs":[],"name":"Error","outputs":[],"stateMutability":"pure","type":"function"}]`}, + ` + "math/big" + + "github.com/ethereum/go-ethereum/accounts/abi/bind" + "github.com/ethereum/go-ethereum/accounts/abi/bind/backends" + "github.com/ethereum/go-ethereum/core" + "github.com/ethereum/go-ethereum/crypto" + "github.com/ethereum/go-ethereum/eth/ethconfig" + `, + ` + var ( + key, _ = crypto.GenerateKey() + user, _ = bind.NewKeyedTransactorWithChainID(key, big.NewInt(1337)) + sim = backends.NewSimulatedBackend(core.GenesisAlloc{user.From: {Balance: big.NewInt(1000000000000000000)}}, ethconfig.Defaults.Miner.GasCeil) + ) + defer sim.Close() + + _, tx, contract, err := DeployNewErrors(user, sim) + if err != nil { + t.Fatal(err) + } + sim.Commit() + _, err = bind.WaitDeployed(nil, sim, tx) + if err != nil { + t.Error(err) + } + if err := contract.Error(new(bind.CallOpts)); err == nil { + t.Fatalf("expected contract to throw error") + } + // TODO (MariusVanDerWijden unpack error using abigen + // once that is implemented `, nil, nil, diff --git a/accounts/abi/error.go b/accounts/abi/error.go index f0f71b6c91..3d1a4877dd 100644 --- a/accounts/abi/error.go +++ b/accounts/abi/error.go @@ -1,4 +1,4 @@ -// Copyright 2016 The go-ethereum Authors +// Copyright 2021 The go-ethereum Authors // This file is part of the go-ethereum library. // // The go-ethereum library is free software: you can redistribute it and/or modify @@ -17,66 +17,75 @@ package abi import ( + "bytes" "errors" "fmt" - "reflect" -) + "strings" -var ( - errBadBool = errors.New("abi: improperly encoded boolean value") + "github.com/ethereum/go-ethereum/common" + "github.com/ethereum/go-ethereum/crypto" ) -// formatSliceString formats the reflection kind with the given slice size -// and returns a formatted string representation. -func formatSliceString(kind reflect.Kind, sliceSize int) string { - if sliceSize == -1 { - return fmt.Sprintf("[]%v", kind) - } - return fmt.Sprintf("[%d]%v", sliceSize, kind) +type Error struct { + Name string + Inputs Arguments + str string + // Sig contains the string signature according to the ABI spec. + // e.g. event foo(uint32 a, int b) = "foo(uint32,int256)" + // Please note that "int" is substitute for its canonical representation "int256" + Sig string + // ID returns the canonical representation of the event's signature used by the + // abi definition to identify event names and types. + ID common.Hash } -// sliceTypeCheck checks that the given slice can by assigned to the reflection -// type in t. -func sliceTypeCheck(t Type, val reflect.Value) error { - if val.Kind() != reflect.Slice && val.Kind() != reflect.Array { - return typeErr(formatSliceString(t.GetType().Kind(), t.Size), val.Type()) +func NewError(name string, inputs Arguments) Error { + // sanitize inputs to remove inputs without names + // and precompute string and sig representation. + names := make([]string, len(inputs)) + types := make([]string, len(inputs)) + for i, input := range inputs { + if input.Name == "" { + inputs[i] = Argument{ + Name: fmt.Sprintf("arg%d", i), + Indexed: input.Indexed, + Type: input.Type, + } + } else { + inputs[i] = input + } + // string representation + names[i] = fmt.Sprintf("%v %v", input.Type, inputs[i].Name) + if input.Indexed { + names[i] = fmt.Sprintf("%v indexed %v", input.Type, inputs[i].Name) + } + // sig representation + types[i] = input.Type.String() } - if t.T == ArrayTy && val.Len() != t.Size { - return typeErr(formatSliceString(t.Elem.GetType().Kind(), t.Size), formatSliceString(val.Type().Elem().Kind(), val.Len())) - } + str := fmt.Sprintf("error %v(%v)", name, strings.Join(names, ", ")) + sig := fmt.Sprintf("%v(%v)", name, strings.Join(types, ",")) + id := common.BytesToHash(crypto.Keccak256([]byte(sig))) - if t.Elem.T == SliceTy || t.Elem.T == ArrayTy { - if val.Len() > 0 { - return sliceTypeCheck(*t.Elem, val.Index(0)) - } + return Error{ + Name: name, + Inputs: inputs, + str: str, + Sig: sig, + ID: id, } +} - if val.Type().Elem().Kind() != t.Elem.GetType().Kind() { - return typeErr(formatSliceString(t.Elem.GetType().Kind(), t.Size), val.Type()) - } - return nil +func (e *Error) String() string { + return e.str } -// typeCheck checks that the given reflection value can be assigned to the reflection -// type in t. -func typeCheck(t Type, value reflect.Value) error { - if t.T == SliceTy || t.T == ArrayTy { - return sliceTypeCheck(t, value) +func (e *Error) Unpack(data []byte) (interface{}, error) { + if len(data) < 4 { + return "", errors.New("invalid data for unpacking") } - - // Check base type validity. Element types will be checked later on. - if t.GetType().Kind() != value.Kind() { - return typeErr(t.GetType().Kind(), value.Kind()) - } else if t.T == FixedBytesTy && t.Size != value.Len() { - return typeErr(t.GetType(), value.Type()) - } else { - return nil + if !bytes.Equal(data[:4], e.ID[:4]) { + return "", errors.New("invalid data for unpacking") } - -} - -// typeErr returns a formatted type casting error. -func typeErr(expected, got interface{}) error { - return fmt.Errorf("abi: cannot use %v as type %v as argument", got, expected) + return e.Inputs.Unpack(data[4:]) } diff --git a/accounts/abi/error_handling.go b/accounts/abi/error_handling.go new file mode 100644 index 0000000000..f0f71b6c91 --- /dev/null +++ b/accounts/abi/error_handling.go @@ -0,0 +1,82 @@ +// Copyright 2016 The go-ethereum Authors +// This file is part of the go-ethereum library. +// +// The go-ethereum library is free software: you can redistribute it and/or modify +// it under the terms of the GNU Lesser General Public License as published by +// the Free Software Foundation, either version 3 of the License, or +// (at your option) any later version. +// +// The go-ethereum library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public License +// along with the go-ethereum library. If not, see . + +package abi + +import ( + "errors" + "fmt" + "reflect" +) + +var ( + errBadBool = errors.New("abi: improperly encoded boolean value") +) + +// formatSliceString formats the reflection kind with the given slice size +// and returns a formatted string representation. +func formatSliceString(kind reflect.Kind, sliceSize int) string { + if sliceSize == -1 { + return fmt.Sprintf("[]%v", kind) + } + return fmt.Sprintf("[%d]%v", sliceSize, kind) +} + +// sliceTypeCheck checks that the given slice can by assigned to the reflection +// type in t. +func sliceTypeCheck(t Type, val reflect.Value) error { + if val.Kind() != reflect.Slice && val.Kind() != reflect.Array { + return typeErr(formatSliceString(t.GetType().Kind(), t.Size), val.Type()) + } + + if t.T == ArrayTy && val.Len() != t.Size { + return typeErr(formatSliceString(t.Elem.GetType().Kind(), t.Size), formatSliceString(val.Type().Elem().Kind(), val.Len())) + } + + if t.Elem.T == SliceTy || t.Elem.T == ArrayTy { + if val.Len() > 0 { + return sliceTypeCheck(*t.Elem, val.Index(0)) + } + } + + if val.Type().Elem().Kind() != t.Elem.GetType().Kind() { + return typeErr(formatSliceString(t.Elem.GetType().Kind(), t.Size), val.Type()) + } + return nil +} + +// typeCheck checks that the given reflection value can be assigned to the reflection +// type in t. +func typeCheck(t Type, value reflect.Value) error { + if t.T == SliceTy || t.T == ArrayTy { + return sliceTypeCheck(t, value) + } + + // Check base type validity. Element types will be checked later on. + if t.GetType().Kind() != value.Kind() { + return typeErr(t.GetType().Kind(), value.Kind()) + } else if t.T == FixedBytesTy && t.Size != value.Len() { + return typeErr(t.GetType(), value.Type()) + } else { + return nil + } + +} + +// typeErr returns a formatted type casting error. +func typeErr(expected, got interface{}) error { + return fmt.Errorf("abi: cannot use %v as type %v as argument", got, expected) +}