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account/abi: handle solidity panic revert (ethereum#27868)
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islishude authored and devopsbo3 committed Nov 10, 2023
1 parent 8398b70 commit be49691
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Showing 2 changed files with 56 additions and 12 deletions.
66 changes: 54 additions & 12 deletions accounts/abi/abi.go
Original file line number Diff line number Diff line change
Expand Up @@ -22,6 +22,7 @@ import (
"errors"
"fmt"
"io"
"math/big"

"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/crypto"
Expand Down Expand Up @@ -246,24 +247,65 @@ func (abi *ABI) HasReceive() bool {
// revertSelector is a special function selector for revert reason unpacking.
var revertSelector = crypto.Keccak256([]byte("Error(string)"))[:4]

// panicSelector is a special function selector for panic reason unpacking.
var panicSelector = crypto.Keccak256([]byte("Panic(uint256)"))[:4]

// panicReasons map is for readable panic codes
// see this linkage for the deails
// https://docs.soliditylang.org/en/v0.8.21/control-structures.html#panic-via-assert-and-error-via-require
// the reason string list is copied from ether.js
// https://github.com/ethers-io/ethers.js/blob/fa3a883ff7c88611ce766f58bdd4b8ac90814470/src.ts/abi/interface.ts#L207-L218
var panicReasons = map[uint64]string{
0x00: "generic panic",
0x01: "assert(false)",
0x11: "arithmetic underflow or overflow",
0x12: "division or modulo by zero",
0x21: "enum overflow",
0x22: "invalid encoded storage byte array accessed",
0x31: "out-of-bounds array access; popping on an empty array",
0x32: "out-of-bounds access of an array or bytesN",
0x41: "out of memory",
0x51: "uninitialized function",
}

// UnpackRevert resolves the abi-encoded revert reason. According to the solidity
// spec https://solidity.readthedocs.io/en/latest/control-structures.html#revert,
// the provided revert reason is abi-encoded as if it were a call to a function
// `Error(string)`. So it's a special tool for it.
// the provided revert reason is abi-encoded as if it were a call to function
// `Error(string)` or `Panic(uint256)`. So it's a special tool for it.
func UnpackRevert(data []byte) (string, error) {
if len(data) < 4 {
return "", errors.New("invalid data for unpacking")
}
if !bytes.Equal(data[:4], revertSelector) {
switch {
case bytes.Equal(data[:4], revertSelector):
typ, err := NewType("string", "", nil)
if err != nil {
return "", err
}
unpacked, err := (Arguments{{Type: typ}}).Unpack(data[4:])
if err != nil {
return "", err
}
return unpacked[0].(string), nil
case bytes.Equal(data[:4], panicSelector):
typ, err := NewType("uint256", "", nil)
if err != nil {
return "", err
}
unpacked, err := (Arguments{{Type: typ}}).Unpack(data[4:])
if err != nil {
return "", err
}
pCode := unpacked[0].(*big.Int)
// uint64 safety check for future
// but the code is not bigger than MAX(uint64) now
if pCode.IsUint64() {
if reason, ok := panicReasons[pCode.Uint64()]; ok {
return reason, nil
}
}
return fmt.Sprintf("unknown panic code: %#x", pCode), nil
default:
return "", errors.New("invalid data for unpacking")
}
typ, err := NewType("string", "", nil)
if err != nil {
return "", err
}
unpacked, err := (Arguments{{Type: typ}}).Unpack(data[4:])
if err != nil {
return "", err
}
return unpacked[0].(string), nil
}
2 changes: 2 additions & 0 deletions accounts/abi/abi_test.go
Original file line number Diff line number Diff line change
Expand Up @@ -1173,6 +1173,8 @@ func TestUnpackRevert(t *testing.T) {
{"", "", errors.New("invalid data for unpacking")},
{"08c379a1", "", errors.New("invalid data for unpacking")},
{"08c379a00000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000d72657665727420726561736f6e00000000000000000000000000000000000000", "revert reason", nil},
{"4e487b710000000000000000000000000000000000000000000000000000000000000000", "generic panic", nil},
{"4e487b7100000000000000000000000000000000000000000000000000000000000000ff", "unknown panic code: 0xff", nil},
}
for index, c := range cases {
t.Run(fmt.Sprintf("case %d", index), func(t *testing.T) {
Expand Down

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