diff --git a/rlp/decode.go b/rlp/decode.go index 7d95af02b..712d9fcf1 100644 --- a/rlp/decode.go +++ b/rlp/decode.go @@ -54,7 +54,7 @@ type Decoder interface { // To decode into a Go string, the input must be an RLP string. The // bytes are taken as-is and will not necessarily be valid UTF-8. // -// To decode into an integer type, the input must also be an RLP +// To decode into an unsigned integer type, the input must also be an RLP // string. The bytes are interpreted as a big endian representation of // the integer. If the RLP string is larger than the bit size of the // type, Decode will return an error. Decode also supports *big.Int. @@ -66,8 +66,9 @@ type Decoder interface { // []interface{}, for RLP lists // []byte, for RLP strings // -// Non-empty interface types are not supported, nor are bool, float32, -// float64, maps, channel types and functions. +// Non-empty interface types are not supported, nor are booleans, +// signed integers, floating point numbers, maps, channels and +// functions. func Decode(r io.Reader, val interface{}) error { return NewStream(r).Decode(val) } @@ -81,37 +82,58 @@ func (err decodeError) Error() string { return fmt.Sprintf("rlp: %s for %v", err.msg, err.typ) } -func makeNumDecoder(typ reflect.Type) decoder { - kind := typ.Kind() - switch { - case kind <= reflect.Int64: - return decodeInt - case kind <= reflect.Uint64: - return decodeUint - default: - panic("fallthrough") +func wrapStreamError(err error, typ reflect.Type) error { + switch err { + case ErrExpectedList: + return decodeError{"expected input list", typ} + case ErrExpectedString: + return decodeError{"expected input string or byte", typ} + case errUintOverflow: + return decodeError{"input string too long", typ} + case errNotAtEOL: + return decodeError{"input list has too many elements", typ} } + return err } -func decodeInt(s *Stream, val reflect.Value) error { - typ := val.Type() - num, err := s.uint(typ.Bits()) - if err == errUintOverflow { - return decodeError{"input string too long", typ} - } else if err != nil { - return err +var ( + decoderInterface = reflect.TypeOf(new(Decoder)).Elem() + bigInt = reflect.TypeOf(big.Int{}) +) + +func makeDecoder(typ reflect.Type) (dec decoder, err error) { + kind := typ.Kind() + switch { + case typ.Implements(decoderInterface): + return decodeDecoder, nil + case kind != reflect.Ptr && reflect.PtrTo(typ).Implements(decoderInterface): + return decodeDecoderNoPtr, nil + case typ.AssignableTo(reflect.PtrTo(bigInt)): + return decodeBigInt, nil + case typ.AssignableTo(bigInt): + return decodeBigIntNoPtr, nil + case isUint(kind): + return decodeUint, nil + case kind == reflect.String: + return decodeString, nil + case kind == reflect.Slice || kind == reflect.Array: + return makeListDecoder(typ) + case kind == reflect.Struct: + return makeStructDecoder(typ) + case kind == reflect.Ptr: + return makePtrDecoder(typ) + case kind == reflect.Interface && typ.NumMethod() == 0: + return decodeInterface, nil + default: + return nil, fmt.Errorf("rlp: type %v is not RLP-serializable", typ) } - val.SetInt(int64(num)) - return nil } func decodeUint(s *Stream, val reflect.Value) error { typ := val.Type() num, err := s.uint(typ.Bits()) - if err == errUintOverflow { - return decodeError{"input string too big", typ} - } else if err != nil { - return err + if err != nil { + return wrapStreamError(err, val.Type()) } val.SetUint(num) return nil @@ -120,7 +142,7 @@ func decodeUint(s *Stream, val reflect.Value) error { func decodeString(s *Stream, val reflect.Value) error { b, err := s.Bytes() if err != nil { - return err + return wrapStreamError(err, val.Type()) } val.SetString(string(b)) return nil @@ -133,7 +155,7 @@ func decodeBigIntNoPtr(s *Stream, val reflect.Value) error { func decodeBigInt(s *Stream, val reflect.Value) error { b, err := s.Bytes() if err != nil { - return err + return wrapStreamError(err, val.Type()) } i := val.Interface().(*big.Int) if i == nil { @@ -144,8 +166,6 @@ func decodeBigInt(s *Stream, val reflect.Value) error { return nil } -const maxInt = int(^uint(0) >> 1) - func makeListDecoder(typ reflect.Type) (decoder, error) { etype := typ.Elem() if etype.Kind() == reflect.Uint8 && !reflect.PtrTo(etype).Implements(decoderInterface) { @@ -159,55 +179,41 @@ func makeListDecoder(typ reflect.Type) (decoder, error) { if err != nil { return nil, err } - var maxLen = maxInt + if typ.Kind() == reflect.Array { - maxLen = typ.Len() + return func(s *Stream, val reflect.Value) error { + return decodeListArray(s, val, etypeinfo.decoder) + }, nil } - dec := func(s *Stream, val reflect.Value) error { - return decodeList(s, val, etypeinfo.decoder, maxLen) - } - return dec, nil + return func(s *Stream, val reflect.Value) error { + return decodeListSlice(s, val, etypeinfo.decoder) + }, nil } -// decodeList decodes RLP list elements into slices and arrays. -// -// The approach here is stolen from package json, although we differ -// in the semantics for arrays. package json discards remaining -// elements that would not fit into the array. We generate an error in -// this case because we'd be losing information. -func decodeList(s *Stream, val reflect.Value, elemdec decoder, maxelem int) error { +func decodeListSlice(s *Stream, val reflect.Value, elemdec decoder) error { size, err := s.List() if err != nil { - return err + return wrapStreamError(err, val.Type()) } if size == 0 { - if val.Kind() == reflect.Slice { - val.Set(reflect.MakeSlice(val.Type(), 0, 0)) - } else { - zero(val, 0) - } + val.Set(reflect.MakeSlice(val.Type(), 0, 0)) return s.ListEnd() } i := 0 - for { - if i > maxelem { - return decodeError{"input list has too many elements", val.Type()} + for ; ; i++ { + // grow slice if necessary + if i >= val.Cap() { + newcap := val.Cap() + val.Cap()/2 + if newcap < 4 { + newcap = 4 + } + newv := reflect.MakeSlice(val.Type(), val.Len(), newcap) + reflect.Copy(newv, val) + val.Set(newv) } - if val.Kind() == reflect.Slice { - // grow slice if necessary - if i >= val.Cap() { - newcap := val.Cap() + val.Cap()/2 - if newcap < 4 { - newcap = 4 - } - newv := reflect.MakeSlice(val.Type(), val.Len(), newcap) - reflect.Copy(newv, val) - val.Set(newv) - } - if i >= val.Len() { - val.SetLen(i + 1) - } + if i >= val.Len() { + val.SetLen(i + 1) } // decode into element if err := elemdec(s, val.Index(i)); err == EOL { @@ -215,26 +221,49 @@ func decodeList(s *Stream, val reflect.Value, elemdec decoder, maxelem int) erro } else if err != nil { return err } - i++ } if i < val.Len() { - if val.Kind() == reflect.Array { - // zero the rest of the array. - zero(val, i) - } else { - val.SetLen(i) - } + val.SetLen(i) } return s.ListEnd() } +func decodeListArray(s *Stream, val reflect.Value, elemdec decoder) error { + size, err := s.List() + if err != nil { + return err + } + if size == 0 { + zero(val, 0) + return s.ListEnd() + } + + // The approach here is stolen from package json, although we differ + // in the semantics for arrays. package json discards remaining + // elements that would not fit into the array. We generate an error in + // this case because we'd be losing information. + vlen := val.Len() + i := 0 + for ; i < vlen; i++ { + if err := elemdec(s, val.Index(i)); err == EOL { + break + } else if err != nil { + return err + } + } + if i < vlen { + zero(val, i) + } + return wrapStreamError(s.ListEnd(), val.Type()) +} + func decodeByteSlice(s *Stream, val reflect.Value) error { kind, _, err := s.Kind() if err != nil { return err } if kind == List { - return decodeList(s, val, decodeUint, maxInt) + return decodeListSlice(s, val, decodeUint) } b, err := s.Bytes() if err == nil { @@ -251,14 +280,14 @@ func decodeByteArray(s *Stream, val reflect.Value) error { switch kind { case Byte: if val.Len() == 0 { - return decodeError{"input string too big", val.Type()} + return decodeError{"input string too long", val.Type()} } bv, _ := s.Uint() val.Index(0).SetUint(bv) zero(val, 1) case String: if uint64(val.Len()) < size { - return decodeError{"input string too big", val.Type()} + return decodeError{"input string too long", val.Type()} } slice := val.Slice(0, int(size)).Interface().([]byte) if err := s.readFull(slice); err != nil { @@ -266,14 +295,15 @@ func decodeByteArray(s *Stream, val reflect.Value) error { } zero(val, int(size)) case List: - return decodeList(s, val, decodeUint, val.Len()) + return decodeListArray(s, val, decodeUint) } return nil } func zero(val reflect.Value, start int) { z := reflect.Zero(val.Type().Elem()) - for i := start; i < val.Len(); i++ { + end := val.Len() + for i := start; i < end; i++ { val.Index(i).Set(z) } } @@ -296,7 +326,7 @@ func makeStructDecoder(typ reflect.Type) (decoder, error) { } dec := func(s *Stream, val reflect.Value) (err error) { if _, err = s.List(); err != nil { - return err + return wrapStreamError(err, typ) } for _, f := range fields { err = f.info.decoder(s, val.Field(f.index)) @@ -307,10 +337,7 @@ func makeStructDecoder(typ reflect.Type) (decoder, error) { return err } } - if err = s.ListEnd(); err == errNotAtEOL { - err = decodeError{"input list has too many elements", typ} - } - return err + return wrapStreamError(s.ListEnd(), typ) } return dec, nil } @@ -348,7 +375,7 @@ func decodeInterface(s *Stream, val reflect.Value) error { } if kind == List { slice := reflect.New(ifsliceType).Elem() - if err := decodeList(s, slice, decodeInterface, maxInt); err != nil { + if err := decodeListSlice(s, slice, decodeInterface); err != nil { return err } val.Set(slice) diff --git a/rlp/decode_test.go b/rlp/decode_test.go index 3b60234dd..7a1743937 100644 --- a/rlp/decode_test.go +++ b/rlp/decode_test.go @@ -171,7 +171,7 @@ func TestDecodeErrors(t *testing.T) { t.Errorf("Decode(r, new(chan bool)) error mismatch, got %q, want %q", err, expectErr) } - if err := Decode(r, new(int)); err != io.EOF { + if err := Decode(r, new(uint)); err != io.EOF { t.Errorf("Decode(r, new(int)) error mismatch, got %q, want %q", err, io.EOF) } } @@ -184,12 +184,12 @@ type decodeTest struct { } type simplestruct struct { - A int + A uint B string } type recstruct struct { - I int + I uint Child *recstruct } @@ -202,7 +202,7 @@ var ( var ( sharedByteArray [5]byte - sharedPtr = new(*int) + sharedPtr = new(*uint) ) var decodeTests = []decodeTest{ @@ -213,17 +213,17 @@ var decodeTests = []decodeTest{ {input: "820505", ptr: new(uint32), value: uint32(0x0505)}, {input: "83050505", ptr: new(uint32), value: uint32(0x050505)}, {input: "8405050505", ptr: new(uint32), value: uint32(0x05050505)}, - {input: "850505050505", ptr: new(uint32), error: "rlp: input string too big for uint32"}, - {input: "C0", ptr: new(uint32), error: ErrExpectedString.Error()}, + {input: "850505050505", ptr: new(uint32), error: "rlp: input string too long for uint32"}, + {input: "C0", ptr: new(uint32), error: "rlp: expected input string or byte for uint32"}, // slices - {input: "C0", ptr: new([]int), value: []int{}}, - {input: "C80102030405060708", ptr: new([]int), value: []int{1, 2, 3, 4, 5, 6, 7, 8}}, + {input: "C0", ptr: new([]uint), value: []uint{}}, + {input: "C80102030405060708", ptr: new([]uint), value: []uint{1, 2, 3, 4, 5, 6, 7, 8}}, // arrays - {input: "C0", ptr: new([5]int), value: [5]int{}}, - {input: "C50102030405", ptr: new([5]int), value: [5]int{1, 2, 3, 4, 5}}, - {input: "C6010203040506", ptr: new([5]int), error: "rlp: input list has too many elements for [5]int"}, + {input: "C0", ptr: new([5]uint), value: [5]uint{}}, + {input: "C50102030405", ptr: new([5]uint), value: [5]uint{1, 2, 3, 4, 5}}, + {input: "C6010203040506", ptr: new([5]uint), error: "rlp: input list has too many elements for [5]uint"}, // byte slices {input: "01", ptr: new([]byte), value: []byte{1}}, @@ -231,7 +231,7 @@ var decodeTests = []decodeTest{ {input: "8D6162636465666768696A6B6C6D", ptr: new([]byte), value: []byte("abcdefghijklm")}, {input: "C0", ptr: new([]byte), value: []byte{}}, {input: "C3010203", ptr: new([]byte), value: []byte{1, 2, 3}}, - {input: "C3820102", ptr: new([]byte), error: "rlp: input string too big for uint8"}, + {input: "C3820102", ptr: new([]byte), error: "rlp: input string too long for uint8"}, // byte arrays {input: "01", ptr: new([5]byte), value: [5]byte{1}}, @@ -239,8 +239,8 @@ var decodeTests = []decodeTest{ {input: "850102030405", ptr: new([5]byte), value: [5]byte{1, 2, 3, 4, 5}}, {input: "C0", ptr: new([5]byte), value: [5]byte{}}, {input: "C3010203", ptr: new([5]byte), value: [5]byte{1, 2, 3, 0, 0}}, - {input: "C3820102", ptr: new([5]byte), error: "rlp: input string too big for uint8"}, - {input: "86010203040506", ptr: new([5]byte), error: "rlp: input string too big for [5]uint8"}, + {input: "C3820102", ptr: new([5]byte), error: "rlp: input string too long for uint8"}, + {input: "86010203040506", ptr: new([5]byte), error: "rlp: input string too long for [5]uint8"}, {input: "850101", ptr: new([5]byte), error: io.ErrUnexpectedEOF.Error()}, // byte array reuse (should be zeroed) @@ -254,19 +254,19 @@ var decodeTests = []decodeTest{ // zero sized byte arrays {input: "80", ptr: new([0]byte), value: [0]byte{}}, {input: "C0", ptr: new([0]byte), value: [0]byte{}}, - {input: "01", ptr: new([0]byte), error: "rlp: input string too big for [0]uint8"}, - {input: "8101", ptr: new([0]byte), error: "rlp: input string too big for [0]uint8"}, + {input: "01", ptr: new([0]byte), error: "rlp: input string too long for [0]uint8"}, + {input: "8101", ptr: new([0]byte), error: "rlp: input string too long for [0]uint8"}, // strings {input: "00", ptr: new(string), value: "\000"}, {input: "8D6162636465666768696A6B6C6D", ptr: new(string), value: "abcdefghijklm"}, - {input: "C0", ptr: new(string), error: ErrExpectedString.Error()}, + {input: "C0", ptr: new(string), error: "rlp: expected input string or byte for string"}, // big ints {input: "01", ptr: new(*big.Int), value: big.NewInt(1)}, {input: "89FFFFFFFFFFFFFFFFFF", ptr: new(*big.Int), value: veryBigInt}, {input: "10", ptr: new(big.Int), value: *big.NewInt(16)}, // non-pointer also works - {input: "C0", ptr: new(*big.Int), error: ErrExpectedString.Error()}, + {input: "C0", ptr: new(*big.Int), error: "rlp: expected input string or byte for *big.Int"}, // structs {input: "C0", ptr: new(simplestruct), value: simplestruct{0, ""}}, @@ -280,17 +280,17 @@ var decodeTests = []decodeTest{ }, // pointers - {input: "00", ptr: new(*int), value: (*int)(nil)}, - {input: "80", ptr: new(*int), value: (*int)(nil)}, - {input: "C0", ptr: new(*int), value: (*int)(nil)}, - {input: "07", ptr: new(*int), value: intp(7)}, - {input: "8108", ptr: new(*int), value: intp(8)}, - {input: "C109", ptr: new(*[]int), value: &[]int{9}}, + {input: "00", ptr: new(*uint), value: (*uint)(nil)}, + {input: "80", ptr: new(*uint), value: (*uint)(nil)}, + {input: "C0", ptr: new(*uint), value: (*uint)(nil)}, + {input: "07", ptr: new(*uint), value: uintp(7)}, + {input: "8108", ptr: new(*uint), value: uintp(8)}, + {input: "C109", ptr: new(*[]uint), value: &[]uint{9}}, {input: "C58403030303", ptr: new(*[][]byte), value: &[][]byte{{3, 3, 3, 3}}}, // pointer should be reset to nil - {input: "05", ptr: sharedPtr, value: intp(5)}, - {input: "80", ptr: sharedPtr, value: (*int)(nil)}, + {input: "05", ptr: sharedPtr, value: uintp(5)}, + {input: "80", ptr: sharedPtr, value: (*uint)(nil)}, // interface{} {input: "00", ptr: new(interface{}), value: []byte{0}}, @@ -301,7 +301,7 @@ var decodeTests = []decodeTest{ {input: "C50183040404", ptr: new(interface{}), value: []interface{}{[]byte{1}, []byte{4, 4, 4}}}, } -func intp(i int) *int { return &i } +func uintp(i uint) *uint { return &i } func runTests(t *testing.T, decode func([]byte, interface{}) error) { for i, test := range decodeTests { @@ -434,8 +434,8 @@ func ExampleDecode() { input, _ := hex.DecodeString("C90A1486666F6F626172") type example struct { - A, B int - private int // private fields are ignored + A, B uint + private uint // private fields are ignored String string } @@ -447,7 +447,7 @@ func ExampleDecode() { fmt.Printf("Decoded value: %#v\n", s) } // Output: - // Decoded value: rlp.example{A:10, B:20, private:0, String:"foobar"} + // Decoded value: rlp.example{A:0xa, B:0x14, private:0x0, String:"foobar"} } func ExampleStream() { diff --git a/rlp/typecache.go b/rlp/typecache.go index 75dbb43c2..52e68a3c5 100644 --- a/rlp/typecache.go +++ b/rlp/typecache.go @@ -1,8 +1,6 @@ package rlp import ( - "fmt" - "math/big" "reflect" "sync" ) @@ -51,41 +49,14 @@ func cachedTypeInfo1(typ reflect.Type) (*typeinfo, error) { return typeCache[typ], err } -var ( - decoderInterface = reflect.TypeOf(new(Decoder)).Elem() - bigInt = reflect.TypeOf(big.Int{}) -) - func genTypeInfo(typ reflect.Type) (info *typeinfo, err error) { info = new(typeinfo) - kind := typ.Kind() - switch { - case typ.Implements(decoderInterface): - info.decoder = decodeDecoder - case kind != reflect.Ptr && reflect.PtrTo(typ).Implements(decoderInterface): - info.decoder = decodeDecoderNoPtr - case typ.AssignableTo(reflect.PtrTo(bigInt)): - info.decoder = decodeBigInt - case typ.AssignableTo(bigInt): - info.decoder = decodeBigIntNoPtr - case isInteger(kind): - info.decoder = makeNumDecoder(typ) - case kind == reflect.String: - info.decoder = decodeString - case kind == reflect.Slice || kind == reflect.Array: - info.decoder, err = makeListDecoder(typ) - case kind == reflect.Struct: - info.decoder, err = makeStructDecoder(typ) - case kind == reflect.Ptr: - info.decoder, err = makePtrDecoder(typ) - case kind == reflect.Interface && typ.NumMethod() == 0: - info.decoder = decodeInterface - default: - err = fmt.Errorf("rlp: type %v is not RLP-serializable", typ) + if info.decoder, err = makeDecoder(typ); err != nil { + return nil, err } - return info, err + return info, nil } -func isInteger(k reflect.Kind) bool { - return k >= reflect.Int && k <= reflect.Uintptr +func isUint(k reflect.Kind) bool { + return k >= reflect.Uint && k <= reflect.Uintptr }