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plugeth/rlp/decode_test.go

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21 KiB
Go
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package rlp
import (
"bytes"
"encoding/hex"
"fmt"
"io"
"math/big"
"reflect"
"testing"
)
func TestStreamKind(t *testing.T) {
tests := []struct {
input string
wantKind Kind
wantLen uint64
}{
{"00", Byte, 0},
{"01", Byte, 0},
{"7F", Byte, 0},
{"80", String, 0},
{"B7", String, 55},
{"B90400", String, 1024},
{"BFFFFFFFFFFFFFFFFF", String, ^uint64(0)},
{"C0", List, 0},
{"C8", List, 8},
{"F7", List, 55},
{"F90400", List, 1024},
{"FFFFFFFFFFFFFFFFFF", List, ^uint64(0)},
}
for i, test := range tests {
// using plainReader to inhibit input limit errors.
s := NewStream(newPlainReader(unhex(test.input)), 0)
kind, len, err := s.Kind()
if err != nil {
t.Errorf("test %d: Kind returned error: %v", i, err)
continue
}
if kind != test.wantKind {
t.Errorf("test %d: kind mismatch: got %d, want %d", i, kind, test.wantKind)
}
if len != test.wantLen {
t.Errorf("test %d: len mismatch: got %d, want %d", i, len, test.wantLen)
}
}
}
func TestNewListStream(t *testing.T) {
ls := NewListStream(bytes.NewReader(unhex("0101010101")), 3)
if k, size, err := ls.Kind(); k != List || size != 3 || err != nil {
t.Errorf("Kind() returned (%v, %d, %v), expected (List, 3, nil)", k, size, err)
}
if size, err := ls.List(); size != 3 || err != nil {
t.Errorf("List() returned (%d, %v), expected (3, nil)", size, err)
}
for i := 0; i < 3; i++ {
if val, err := ls.Uint(); val != 1 || err != nil {
t.Errorf("Uint() returned (%d, %v), expected (1, nil)", val, err)
}
}
if err := ls.ListEnd(); err != nil {
t.Errorf("ListEnd() returned %v, expected (3, nil)", err)
}
}
func TestStreamErrors(t *testing.T) {
withoutInputLimit := func(b []byte) *Stream {
return NewStream(newPlainReader(b), 0)
}
withCustomInputLimit := func(limit uint64) func([]byte) *Stream {
return func(b []byte) *Stream {
return NewStream(bytes.NewReader(b), limit)
}
}
type calls []string
tests := []struct {
string
calls
newStream func([]byte) *Stream // uses bytes.Reader if nil
error error
}{
{"C0", calls{"Bytes"}, nil, ErrExpectedString},
{"C0", calls{"Uint"}, nil, ErrExpectedString},
{"89000000000000000001", calls{"Uint"}, nil, errUintOverflow},
{"00", calls{"List"}, nil, ErrExpectedList},
{"80", calls{"List"}, nil, ErrExpectedList},
{"C0", calls{"List", "Uint"}, nil, EOL},
{"C8C9010101010101010101", calls{"List", "Kind"}, nil, ErrElemTooLarge},
{"C3C2010201", calls{"List", "List", "Uint", "Uint", "ListEnd", "Uint"}, nil, EOL},
{"00", calls{"ListEnd"}, nil, errNotInList},
{"C401020304", calls{"List", "Uint", "ListEnd"}, nil, errNotAtEOL},
// Non-canonical integers (e.g. leading zero bytes).
{"00", calls{"Uint"}, nil, ErrCanonInt},
{"820002", calls{"Uint"}, nil, ErrCanonInt},
{"8133", calls{"Uint"}, nil, ErrCanonSize},
{"8156", calls{"Uint"}, nil, nil},
// Size tags must use the smallest possible encoding.
// Leading zero bytes in the size tag are also rejected.
{"8100", calls{"Uint"}, nil, ErrCanonSize},
{"8100", calls{"Bytes"}, nil, ErrCanonSize},
{"B800", calls{"Kind"}, withoutInputLimit, ErrCanonSize},
{"B90000", calls{"Kind"}, withoutInputLimit, ErrCanonSize},
{"B90055", calls{"Kind"}, withoutInputLimit, ErrCanonSize},
{"BA0002FFFF", calls{"Bytes"}, withoutInputLimit, ErrCanonSize},
{"F800", calls{"Kind"}, withoutInputLimit, ErrCanonSize},
{"F90000", calls{"Kind"}, withoutInputLimit, ErrCanonSize},
{"F90055", calls{"Kind"}, withoutInputLimit, ErrCanonSize},
{"FA0002FFFF", calls{"List"}, withoutInputLimit, ErrCanonSize},
// Expected EOF
{"", calls{"Kind"}, nil, io.EOF},
{"", calls{"Uint"}, nil, io.EOF},
{"", calls{"List"}, nil, io.EOF},
{"8158", calls{"Uint", "Uint"}, nil, io.EOF},
{"C0", calls{"List", "ListEnd", "List"}, nil, io.EOF},
// Input limit errors.
{"81", calls{"Bytes"}, nil, ErrValueTooLarge},
{"81", calls{"Uint"}, nil, ErrValueTooLarge},
{"81", calls{"Raw"}, nil, ErrValueTooLarge},
{"BFFFFFFFFFFFFFFFFFFF", calls{"Bytes"}, nil, ErrValueTooLarge},
{"C801", calls{"List"}, nil, ErrValueTooLarge},
// Test for list element size check overflow.
{"CD04040404FFFFFFFFFFFFFFFFFF0303", calls{"List", "Uint", "Uint", "Uint", "Uint", "List"}, nil, ErrElemTooLarge},
// Test for input limit overflow. Since we are counting the limit
// down toward zero in Stream.remaining, reading too far can overflow
// remaining to a large value, effectively disabling the limit.
{"C40102030401", calls{"Raw", "Uint"}, withCustomInputLimit(5), io.EOF},
{"C4010203048158", calls{"Raw", "Uint"}, withCustomInputLimit(6), ErrValueTooLarge},
// Check that the same calls are fine without a limit.
{"C40102030401", calls{"Raw", "Uint"}, withoutInputLimit, nil},
{"C4010203048158", calls{"Raw", "Uint"}, withoutInputLimit, nil},
// Unexpected EOF. This only happens when there is
// no input limit, so the reader needs to be 'dumbed down'.
{"81", calls{"Bytes"}, withoutInputLimit, io.ErrUnexpectedEOF},
{"81", calls{"Uint"}, withoutInputLimit, io.ErrUnexpectedEOF},
{"BFFFFFFFFFFFFFFF", calls{"Bytes"}, withoutInputLimit, io.ErrUnexpectedEOF},
{"C801", calls{"List", "Uint", "Uint"}, withoutInputLimit, io.ErrUnexpectedEOF},
// This test verifies that the input position is advanced
// correctly when calling Bytes for empty strings. Kind can be called
// any number of times in between and doesn't advance.
{"C3808080", calls{
"List", // enter the list
"Bytes", // past first element
"Kind", "Kind", "Kind", // this shouldn't advance
"Bytes", // past second element
"Kind", "Kind", // can't hurt to try
"Bytes", // past final element
"Bytes", // this one should fail
}, nil, EOL},
}
testfor:
for i, test := range tests {
if test.newStream == nil {
test.newStream = func(b []byte) *Stream { return NewStream(bytes.NewReader(b), 0) }
}
s := test.newStream(unhex(test.string))
rs := reflect.ValueOf(s)
for j, call := range test.calls {
fval := rs.MethodByName(call)
ret := fval.Call(nil)
err := "<nil>"
if lastret := ret[len(ret)-1].Interface(); lastret != nil {
err = lastret.(error).Error()
}
if j == len(test.calls)-1 {
want := "<nil>"
if test.error != nil {
want = test.error.Error()
}
if err != want {
t.Log(test)
t.Errorf("test %d: last call (%s) error mismatch\ngot: %s\nwant: %s",
i, call, err, test.error)
}
} else if err != "<nil>" {
t.Log(test)
t.Errorf("test %d: call %d (%s) unexpected error: %q", i, j, call, err)
continue testfor
}
}
}
}
func TestStreamList(t *testing.T) {
s := NewStream(bytes.NewReader(unhex("C80102030405060708")), 0)
len, err := s.List()
if err != nil {
t.Fatalf("List error: %v", err)
}
if len != 8 {
t.Fatalf("List returned invalid length, got %d, want 8", len)
}
for i := uint64(1); i <= 8; i++ {
v, err := s.Uint()
if err != nil {
t.Fatalf("Uint error: %v", err)
}
if i != v {
t.Errorf("Uint returned wrong value, got %d, want %d", v, i)
}
}
if _, err := s.Uint(); err != EOL {
t.Errorf("Uint error mismatch, got %v, want %v", err, EOL)
}
if err = s.ListEnd(); err != nil {
t.Fatalf("ListEnd error: %v", err)
}
}
func TestStreamRaw(t *testing.T) {
s := NewStream(bytes.NewReader(unhex("C58401010101")), 0)
s.List()
want := unhex("8401010101")
raw, err := s.Raw()
if err != nil {
t.Fatal(err)
}
if !bytes.Equal(want, raw) {
t.Errorf("raw mismatch: got %x, want %x", raw, want)
}
}
func TestDecodeErrors(t *testing.T) {
r := bytes.NewReader(nil)
if err := Decode(r, nil); err != errDecodeIntoNil {
t.Errorf("Decode(r, nil) error mismatch, got %q, want %q", err, errDecodeIntoNil)
}
var nilptr *struct{}
if err := Decode(r, nilptr); err != errDecodeIntoNil {
t.Errorf("Decode(r, nilptr) error mismatch, got %q, want %q", err, errDecodeIntoNil)
}
if err := Decode(r, struct{}{}); err != errNoPointer {
t.Errorf("Decode(r, struct{}{}) error mismatch, got %q, want %q", err, errNoPointer)
}
expectErr := "rlp: type chan bool is not RLP-serializable"
if err := Decode(r, new(chan bool)); err == nil || err.Error() != expectErr {
t.Errorf("Decode(r, new(chan bool)) error mismatch, got %q, want %q", err, expectErr)
}
if err := Decode(r, new(uint)); err != io.EOF {
t.Errorf("Decode(r, new(int)) error mismatch, got %q, want %q", err, io.EOF)
}
}
type decodeTest struct {
input string
ptr interface{}
value interface{}
error string
}
type simplestruct struct {
A uint
B string
}
type recstruct struct {
I uint
Child *recstruct `rlp:"nil"`
}
var (
veryBigInt = big.NewInt(0).Add(
big.NewInt(0).Lsh(big.NewInt(0xFFFFFFFFFFFFFF), 16),
big.NewInt(0xFFFF),
)
)
var decodeTests = []decodeTest{
// integers
{input: "05", ptr: new(uint32), value: uint32(5)},
{input: "80", ptr: new(uint32), value: uint32(0)},
{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 long for uint32"},
{input: "C0", ptr: new(uint32), error: "rlp: expected input string or byte for uint32"},
{input: "00", ptr: new(uint32), error: "rlp: non-canonical integer (leading zero bytes) for uint32"},
{input: "8105", ptr: new(uint32), error: "rlp: non-canonical size information for uint32"},
{input: "820004", ptr: new(uint32), error: "rlp: non-canonical integer (leading zero bytes) for uint32"},
{input: "B8020004", ptr: new(uint32), error: "rlp: non-canonical size information for uint32"},
// slices
{input: "C0", ptr: new([]uint), value: []uint{}},
{input: "C80102030405060708", ptr: new([]uint), value: []uint{1, 2, 3, 4, 5, 6, 7, 8}},
{input: "F8020004", ptr: new([]uint), error: "rlp: non-canonical size information for []uint"},
// arrays
{input: "C50102030405", ptr: new([5]uint), value: [5]uint{1, 2, 3, 4, 5}},
{input: "C0", ptr: new([5]uint), error: "rlp: input list has too few elements for [5]uint"},
{input: "C102", ptr: new([5]uint), error: "rlp: input list has too few elements for [5]uint"},
{input: "C6010203040506", ptr: new([5]uint), error: "rlp: input list has too many elements for [5]uint"},
{input: "F8020004", ptr: new([5]uint), error: "rlp: non-canonical size information for [5]uint"},
// zero sized arrays
{input: "C0", ptr: new([0]uint), value: [0]uint{}},
{input: "C101", ptr: new([0]uint), error: "rlp: input list has too many elements for [0]uint"},
// byte slices
{input: "01", ptr: new([]byte), value: []byte{1}},
{input: "80", ptr: new([]byte), value: []byte{}},
{input: "8D6162636465666768696A6B6C6D", ptr: new([]byte), value: []byte("abcdefghijklm")},
{input: "C0", ptr: new([]byte), error: "rlp: expected input string or byte for []uint8"},
{input: "8105", ptr: new([]byte), error: "rlp: non-canonical size information for []uint8"},
// byte arrays
{input: "02", ptr: new([1]byte), value: [1]byte{2}},
{input: "850102030405", ptr: new([5]byte), value: [5]byte{1, 2, 3, 4, 5}},
// byte array errors
{input: "02", ptr: new([5]byte), error: "rlp: input string too short for [5]uint8"},
{input: "80", ptr: new([5]byte), error: "rlp: input string too short for [5]uint8"},
{input: "820000", ptr: new([5]byte), error: "rlp: input string too short for [5]uint8"},
{input: "C0", ptr: new([5]byte), error: "rlp: expected input string or byte for [5]uint8"},
{input: "C3010203", ptr: new([5]byte), error: "rlp: expected input string or byte for [5]uint8"},
{input: "86010203040506", ptr: new([5]byte), error: "rlp: input string too long for [5]uint8"},
{input: "8105", ptr: new([1]byte), error: "rlp: non-canonical size information for [1]uint8"},
// zero sized byte arrays
{input: "80", ptr: new([0]byte), value: [0]byte{}},
{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: "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: "rlp: expected input string or byte for *big.Int"},
{input: "820001", ptr: new(big.Int), error: "rlp: non-canonical integer (leading zero bytes) for *big.Int"},
{input: "8105", ptr: new(big.Int), error: "rlp: non-canonical size information for *big.Int"},
// structs
{
input: "C50583343434",
ptr: new(simplestruct),
value: simplestruct{5, "444"},
},
{
input: "C601C402C203C0",
ptr: new(recstruct),
value: recstruct{1, &recstruct{2, &recstruct{3, nil}}},
},
// struct errors
{
input: "C0",
ptr: new(simplestruct),
error: "rlp: too few elements for rlp.simplestruct",
},
{
input: "C105",
ptr: new(simplestruct),
error: "rlp: too few elements for rlp.simplestruct",
},
{
input: "C7C50583343434C0",
ptr: new([]*simplestruct),
error: "rlp: too few elements for rlp.simplestruct, decoding into ([]*rlp.simplestruct)[1]",
},
{
input: "83222222",
ptr: new(simplestruct),
error: "rlp: expected input list for rlp.simplestruct",
},
{
input: "C3010101",
ptr: new(simplestruct),
error: "rlp: input list has too many elements for rlp.simplestruct",
},
{
input: "C501C3C00000",
ptr: new(recstruct),
error: "rlp: expected input string or byte for uint, decoding into (rlp.recstruct).Child.I",
},
// pointers
{input: "00", ptr: new(*[]byte), value: &[]byte{0}},
{input: "80", ptr: new(*uint), value: uintp(0)},
{input: "C0", ptr: new(*uint), error: "rlp: expected input string or byte for uint"},
{input: "07", ptr: new(*uint), value: uintp(7)},
{input: "8158", ptr: new(*uint), value: uintp(0x58)},
{input: "C109", ptr: new(*[]uint), value: &[]uint{9}},
{input: "C58403030303", ptr: new(*[][]byte), value: &[][]byte{{3, 3, 3, 3}}},
// check that input position is advanced also for empty values.
{input: "C3808005", ptr: new([]*uint), value: []*uint{uintp(0), uintp(0), uintp(5)}},
// interface{}
{input: "00", ptr: new(interface{}), value: []byte{0}},
{input: "01", ptr: new(interface{}), value: []byte{1}},
{input: "80", ptr: new(interface{}), value: []byte{}},
{input: "850505050505", ptr: new(interface{}), value: []byte{5, 5, 5, 5, 5}},
{input: "C0", ptr: new(interface{}), value: []interface{}{}},
{input: "C50183040404", ptr: new(interface{}), value: []interface{}{[]byte{1}, []byte{4, 4, 4}}},
{
input: "C3010203",
ptr: new([]io.Reader),
error: "rlp: type io.Reader is not RLP-serializable",
},
}
func uintp(i uint) *uint { return &i }
func runTests(t *testing.T, decode func([]byte, interface{}) error) {
for i, test := range decodeTests {
input, err := hex.DecodeString(test.input)
if err != nil {
t.Errorf("test %d: invalid hex input %q", i, test.input)
continue
}
err = decode(input, test.ptr)
if err != nil && test.error == "" {
t.Errorf("test %d: unexpected Decode error: %v\ndecoding into %T\ninput %q",
i, err, test.ptr, test.input)
continue
}
if test.error != "" && fmt.Sprint(err) != test.error {
t.Errorf("test %d: Decode error mismatch\ngot %v\nwant %v\ndecoding into %T\ninput %q",
i, err, test.error, test.ptr, test.input)
continue
}
deref := reflect.ValueOf(test.ptr).Elem().Interface()
if err == nil && !reflect.DeepEqual(deref, test.value) {
t.Errorf("test %d: value mismatch\ngot %#v\nwant %#v\ndecoding into %T\ninput %q",
i, deref, test.value, test.ptr, test.input)
}
}
}
func TestDecodeWithByteReader(t *testing.T) {
runTests(t, func(input []byte, into interface{}) error {
return Decode(bytes.NewReader(input), into)
})
}
// plainReader reads from a byte slice but does not
// implement ReadByte. It is also not recognized by the
// size validation. This is useful to test how the decoder
// behaves on a non-buffered input stream.
type plainReader []byte
func newPlainReader(b []byte) io.Reader {
return (*plainReader)(&b)
}
func (r *plainReader) Read(buf []byte) (n int, err error) {
if len(*r) == 0 {
return 0, io.EOF
}
n = copy(buf, *r)
*r = (*r)[n:]
return n, nil
}
func TestDecodeWithNonByteReader(t *testing.T) {
runTests(t, func(input []byte, into interface{}) error {
return Decode(newPlainReader(input), into)
})
}
func TestDecodeStreamReset(t *testing.T) {
s := NewStream(nil, 0)
runTests(t, func(input []byte, into interface{}) error {
s.Reset(bytes.NewReader(input), 0)
return s.Decode(into)
})
}
type testDecoder struct{ called bool }
func (t *testDecoder) DecodeRLP(s *Stream) error {
if _, err := s.Uint(); err != nil {
return err
}
t.called = true
return nil
}
func TestDecodeDecoder(t *testing.T) {
var s struct {
T1 testDecoder
T2 *testDecoder
T3 **testDecoder
}
if err := Decode(bytes.NewReader(unhex("C3010203")), &s); err != nil {
t.Fatalf("Decode error: %v", err)
}
if !s.T1.called {
t.Errorf("DecodeRLP was not called for (non-pointer) testDecoder")
}
if s.T2 == nil {
t.Errorf("*testDecoder has not been allocated")
} else if !s.T2.called {
t.Errorf("DecodeRLP was not called for *testDecoder")
}
if s.T3 == nil || *s.T3 == nil {
t.Errorf("**testDecoder has not been allocated")
} else if !(*s.T3).called {
t.Errorf("DecodeRLP was not called for **testDecoder")
}
}
type byteDecoder byte
func (bd *byteDecoder) DecodeRLP(s *Stream) error {
_, err := s.Uint()
*bd = 255
return err
}
func (bd byteDecoder) called() bool {
return bd == 255
}
// This test verifies that the byte slice/byte array logic
// does not kick in for element types implementing Decoder.
func TestDecoderInByteSlice(t *testing.T) {
var slice []byteDecoder
if err := Decode(bytes.NewReader(unhex("C101")), &slice); err != nil {
t.Errorf("unexpected Decode error %v", err)
} else if !slice[0].called() {
t.Errorf("DecodeRLP not called for slice element")
}
var array [1]byteDecoder
if err := Decode(bytes.NewReader(unhex("C101")), &array); err != nil {
t.Errorf("unexpected Decode error %v", err)
} else if !array[0].called() {
t.Errorf("DecodeRLP not called for array element")
}
}
func ExampleDecode() {
input, _ := hex.DecodeString("C90A1486666F6F626172")
type example struct {
A, B uint
private uint // private fields are ignored
String string
}
var s example
err := Decode(bytes.NewReader(input), &s)
if err != nil {
fmt.Printf("Error: %v\n", err)
} else {
fmt.Printf("Decoded value: %#v\n", s)
}
// Output:
// Decoded value: rlp.example{A:0xa, B:0x14, private:0x0, String:"foobar"}
}
func ExampleDecode_structTagNil() {
// In this example, we'll use the "nil" struct tag to change
// how a pointer-typed field is decoded. The input contains an RLP
// list of one element, an empty string.
input := []byte{0xC1, 0x80}
// This type uses the normal rules.
// The empty input string is decoded as a pointer to an empty Go string.
var normalRules struct {
String *string
}
Decode(bytes.NewReader(input), &normalRules)
fmt.Printf("normal: String = %q\n", *normalRules.String)
// This type uses the struct tag.
// The empty input string is decoded as a nil pointer.
var withEmptyOK struct {
String *string `rlp:"nil"`
}
Decode(bytes.NewReader(input), &withEmptyOK)
fmt.Printf("with nil tag: String = %v\n", withEmptyOK.String)
// Output:
// normal: String = ""
// with nil tag: String = <nil>
}
func ExampleStream() {
input, _ := hex.DecodeString("C90A1486666F6F626172")
s := NewStream(bytes.NewReader(input), 0)
// Check what kind of value lies ahead
kind, size, _ := s.Kind()
fmt.Printf("Kind: %v size:%d\n", kind, size)
// Enter the list
if _, err := s.List(); err != nil {
fmt.Printf("List error: %v\n", err)
return
}
// Decode elements
fmt.Println(s.Uint())
fmt.Println(s.Uint())
fmt.Println(s.Bytes())
// Acknowledge end of list
if err := s.ListEnd(); err != nil {
fmt.Printf("ListEnd error: %v\n", err)
}
// Output:
// Kind: List size:9
// 10 <nil>
// 20 <nil>
// [102 111 111 98 97 114] <nil>
}
func BenchmarkDecode(b *testing.B) {
enc := encodeTestSlice(90000)
b.SetBytes(int64(len(enc)))
b.ReportAllocs()
b.ResetTimer()
for i := 0; i < b.N; i++ {
var s []uint
r := bytes.NewReader(enc)
if err := Decode(r, &s); err != nil {
b.Fatalf("Decode error: %v", err)
}
}
}
func BenchmarkDecodeIntSliceReuse(b *testing.B) {
enc := encodeTestSlice(100000)
b.SetBytes(int64(len(enc)))
b.ReportAllocs()
b.ResetTimer()
var s []uint
for i := 0; i < b.N; i++ {
r := bytes.NewReader(enc)
if err := Decode(r, &s); err != nil {
b.Fatalf("Decode error: %v", err)
}
}
}
func encodeTestSlice(n uint) []byte {
s := make([]uint, n)
for i := uint(0); i < n; i++ {
s[i] = i
}
b, err := EncodeToBytes(s)
if err != nil {
panic(fmt.Sprintf("encode error: %v", err))
}
return b
}
func unhex(str string) []byte {
b, err := hex.DecodeString(str)
if err != nil {
panic(fmt.Sprintf("invalid hex string: %q", str))
}
return b
}
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